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SELCUK, Nurten and ERKAN, Mustafa
- Postharvest biology and technology. 99:9-19
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Food science technology, Sciences technologies alimentaires, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Industries agroalimentaires, Food industries, Industries des fruits et légumes, Fruit and vegetable industries, Angiospermae, Dicotyledones, Rosaceae, Spermatophyta, Antioxydant, Antioxidant, Antioxidante, Après récolte, Postharvest, Postcosecha, Atmosphère modifiée, Modified atmosphere, Atmósfera modificada, Entreposage atmosphère contrôlée, Controlled atmosphere storage, Almacenamiento atmósfera controlada, Fruit, Fruto, Mespilus germanica, Nèfle, Medlar, Níspero, Qualité production, Production quality, Calidad producción, Stockage, Storage, Almacenamiento, Antioxidant activity, Fruit quality, Medlar fruit (Mespilus germanica L.), and Palliflex storage system
- Abstract
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Medlar (Mespilus germanica L. cv. Istanbul) fruit were stored in palliflex controlled atmosphere storage systems of 21% O2 + 0.03% CO2 (PL-1, control), 2% O2 + 5% CO2 (PL-2), 3% O2 +10% CO2 (PL-3) and modified atmosphere packaging (MAP) at 0 °C for 60 days to determine the effects of different O2 and CO2 concentrations on physiological properties, quality attributes and storability. Every 15 days, three replicates of each treatment were evaluated for weight loss, fruit firmness, decay, external browning index, skin color, pH, titratable acidity, total soluble solids, total phenolics, total flavonoids, total condensed tannins, ascorbic acid, antioxidant activity and organic acid and sugar contents. Taste analysis of the fruit was performed after 30,45 and 60 days of storage. The CO2 and O2 concentrations created by the MAP stabilized at 7% and 14%, respectively. Weight loss of fruit stored in MAP was lower (<0.4% at 60 days) than for other treatments. Off-flavors were not detected in any treatment. Storage of medlar fruit under PL-3 was the least effective treatment in delaying fruit ripening (flesh firmness). The incidence and severity of browning, loss of skin color (Ch°) and retaining acceptable taste during 60 days were found the most effective in PL-2 and PL-1 compared to other treatments. Fruit pH increased and titratable acidity decreased during the storage period. Total soluble solids and sugar contents first increased then decreased in all treatments by the end of storage. The fruit stored in PL-2 had higher titratable acidity, total soluble solids and sugar contents than fruit stored in PL-1, PL-3 and MAP at all evaluations. Concentrations of total phenolics, total flavonoids, total condensed tannins, ascorbic acid, associated antioxidant activity and organic acids were affected by the storage atmosphere, decreased during storage. The concentrations of total phenolics, total flavonoids, and antioxidant activity were found the highest in PL-2, PL-1 and MAP treatments, respectively. However, in terms of ascorbic acid and total condensed tannins retention, PL-2 was the most effective treatments. The results indicated that 60 days storage of medlar fruit in the palliflex storage system at 0 °C maintained physiological and biochemical properties of medlar fruit.
2. Arbuscular mycorrhizal fungi facilitate the invasion of Solidago canadensis L. in southeastern China [2014]
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RUYI YANG, GANG ZHOU, SHUTING ZAN, FUYU GUO, NANNAN SU, and JING LI
- Acta oecologica (Montrouge). (61):71-77
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Ecology, Ecologie, Environment, Environnement, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie animale et végétale, Animal and plant ecology, Généralités, General aspects, Autoécologie, Autoecology, Végétaux et champignons, Plants and fungi, Angiospermae, Compositae, Dicotyledones, Mycorhize, Mycorrhiza, Micorriza, Plante herbacée, Herbaceous plant, Planta herbácea, Spermatophyta, Symbionte, Symbiont, Simbionte, Endomycorhize, Endomycorrhiza, Endomicorriza, Fungi, Glomeromycota, Invasion, Invasión, Relation sol plante, Soil plant relation, Relación suelo planta, Solidago canadensis, Structure communauté, Community structure, Estructura comunidad, Functional differences, and Plant-soil feedback
- Abstract
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The significance of arbuscular mycorrhizal fungi (AMF) in the process of plant invasion is still poorly understood. We hypothesize that invasive plants would change local AMF community structure in a way that would benefit themselves but confer less advantages to native plants, thus influencing the extent of plant interactions. An AMF spore community composed of five morphospecies of Glomus with equal density (initial AMF spore community, I-AMF) was constructed to test this hypothesis. The results showed that the invasive species, Solidago canadensis, significantly increased the relative abundance of G. geosperum and G. etunicatum (altered AMF spore community, A-AMF) compared to G. mosseae, which was a dominant morphospecies in the monoculture of native Kummerowia striata. The shift in AMF spore community composition driven by S. canadensis generated functional variation between I-AMF and A-AMF communities. For example, I-AMF increased biomass and nutrient uptake of K. striata in both monocultures and mixtures of K. striata and S. canadensis compared to A-AMF. In contrast, A-AMF significantly enhanced root nitrogen (N) acquisition of S. canadensis grown in mixture. Moreover, mycorrhizal-mediated 15N uptake provided direct evidence that I-AMF and A-AMF differed in their affinities with native and invading species. The non-significant effect of A-AMF on K. striata did not result from allelopathy as root exudates of S. canadensis exhibited positive effects on seed germination and biomass of K. striata under naturally occurring concentrations. When considered together, we found that A-AMF facilitated the invasion of S. canadensis through decreasing competitiveness of the native plant K. striata. The results supported our hypothesis and can be used to improve our understanding of an ecosystem-based perspective towards exotic plant invasion.
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3. Climate effects on inter- and intra-annual larch stemwood anomalies in the Mongolian forest-steppe [2014]
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KHISHIGJARGAL, Mookhor, DULAMSUREN, Choimaa, LEUSCHNER, Hanns Hubert, LEUSCHNER, Christoph, and HAUCK, Markus
- Acta oecologica (Montrouge). 55:113-121
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Ecology, Ecologie, Environment, Environnement, Sciences exactes et technologie, Exact sciences and technology, Terre, ocean, espace, Earth, ocean, space, Geophysique externe, External geophysics, Météorologie, Meteorology, Climatologie. Bioclimatologie. Changement climatique, Climatology. Bioclimatology. Climate change, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Ecologie animale, vegetale et microbienne, Animal, plant and microbial ecology, Ecologie animale et végétale, Animal and plant ecology, Généralités, General aspects, Sylviculture, Forestry, Généralités. Production, biomasse. Qualité des bois et produits forestiers. Ecologie forestière générale, Generalities. Production, biomass. Quality of wood and forest products. General forest ecology, Ecologie forestière générale, General forest ecology, Arbre forestier résineux, Softwood forest tree, Arbol forestal resinoso, Climatologie dynamique, Dynamical climatology, Climatología dinámica, Coniferales, Facteur milieu, Environmental factor, Factor medio, Gymnospermae, Spermatophyta, Anomalie, Anomaly, Anomalía, Bois final, Late wood, Madera final, Changement climatique, Climate change, Cambio climático, Changement global, Global change, Cambio global, Climat, Climate, Clima, Forêt, Forests, Bosque, Larix sibirica, Réchauffement, Warming, Calefacción, Steppe, Estepa, Stress hydrique, Water stress, Estrés hídrico, Drought stress, Forest-steppe, Global warming, Latewood, and Missing rings
- Abstract
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Climate response of tree-ring width and intra-annual wood anomalies were studied in stands of Siberian larch (Larix sibirica) on Mt. Bogd Uul in the forest-steppe ecotone of Mongolia. Climate on Mt. Bogd Uul is characterized by an increase of the annual mean temperature by 1.5 K between 1965 and 2007, the lack of a long-term trend for annual precipitation and, with it, an increase in aridity. Tree-ring width increases with increasing June precipitation of the current year (June) and increasing late summer precipitation of the previous year. In > 100-year old trees, also a negative correlation of tree-ring width with the July temperature of the year prior to tree-ring formation was found. Decreasing tree-ring width with increasing snowfall in December can be explained with the protection of the frost-sensitive eggs of gypsy moth by snow cover, which is a major herbivore of larch in Mongolia and causes reduction in the annual stem increment. The most significant change in wood anatomy was the decline of wide latewood, which is attributable to the increase of summer days with a mean temperature > 15 °C and drought periods in summer without precipitation. Increasing summer drought is also thought to have caused the repeated occurrence of missing rings since the 1960s, which were not observed in the late 19th and early 20th centuries.
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MOMOEDA, Mikio, SASAKI, Hidetaka, TAGASHIRA, Eiko, OGISHIMA, Masayuki, TAKANO, Yuichi, and OCHIAI, Kazunori
- Advances in therapy. 31(3):362-373
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Pharmacology drugs, Pharmacologie, galénique, Sciences biologiques et medicales, Biological and medical sciences, Sciences medicales, Medical sciences, Pharmacologie. Traitements medicamenteux, Pharmacology. Drug treatments, Psychopathologie. Psychiatrie, Psychopathology. Psychiatry, Etude clinique de l'adulte et de l'adolescent, Adult and adolescent clinical studies, Troubles de l'humeur, Mood disorders, Etat dépressif, Depression, Gynecologie. Andrologie. Obstetrique, Gynecology. Andrology. Obstetrics, Pathologie de l'appareil génital femelle, Female genital diseases, Pathologie non tumorale, Non tumoral diseases, Psychologie. Psychanalyse. Psychiatrie, Psychology. Psychoanalysis. Psychiatry, PSYCHOPATHOLOGIE. PSYCHIATRIE, Angiospermae, Dicotyledones, Pathologie de l'appareil génital femelle, Female genital diseases, Aparato genital hembra patología, Pathologie du cycle menstruel, Menstruation disorders, Ciclo menstrual patología, Pharmacognosie, Pharmacognosy, Farmacognosia, Spermatophyta, Trouble de l'humeur, Mood disorder, Trastorno humor, Verbenaceae, Arbre, Tree, Arbol, Efficacité traitement, Treatment efficiency, Eficacia tratamiento, Essai clinique, Clinical trial, Ensayo clínico, Etat dépressif, Depression, Estado depresivo, Extrait, Extract, Extracto, Homme, Human, Hombre, Origine végétale, Plant origin, Origen vegetal, Plante médicinale, Medicinal plant, Planta medicinal, Prospective, Prospectiva, Reproduction, Reproducción, Syndrome prémenstruel, Premenstrual syndrome, Premenstrual síndrome, Toxicité, Toxicity, Toxicidad, Traitement, Treatment, Tratamiento, Vitex agnus-castus, Chaste tree, Herbal medicine, Japanese patients, Phase 3, Prefemin®, and Ze 440
- Abstract
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Introduction: Herbal medicine containing Vitex agnus-castus (VAC) extract is widely used by women with premenstrual syndrome (PMS) in Europe, however, in Japan, clinical evidence remains to be determined. This study attempted to investigate the efficacy and safety profiles of VAC extract in Japanese patients with PMS. Methods: A multi-center, prospective, open-label, single-arm, phase 3 study was performed in Japanese women with PMS and aged 18-44 years. The patients received Prefemin® (Max Zeller Söhne AG, Romanshorn, Switzerland), containing 20 mg of VAC extract, once daily for three menstrual cycles. The efficacy profile was examined based on the intensity of ten PMS symptoms—irritability, depressed mood, anger, headache, bloating, breast fullness, skin disorder, fatigue, drowsiness, and sleeplessness—recorded by patients via a visual analog scale (VAS). In addition, the responder rate was calculated based on the total VAS score defined by the sum of the VAS scores of the first six symptoms mentioned above. Furthermore, physician's global assessment (PGA) scores were recorded. Adverse events including vital signs and laboratory test values were monitored as safety evaluation. Results: Sixty-nine patients received Prefemin®. After the first menstrual cycle, a statistically significant decrease in total VAS score was observed (P < 0.001), and the score continued to diminish for the following two cycles. Each of the ten symptom scores decreased significantly in this manner. In addition, the responder rate increased in a time-dependent manner; the rate at the third menstrual cycle was 91.0%, and almost all of the patients were without symptoms or exhibited only mild symptoms based on PGA. Eight patients exhibited non-serious adverse events, one of which was allergic dermatitis whose causal relationship with VAC was not ruled out. Conclusion: VAC extract improved PMS symptoms in Japanese patients, with no substantial adverse events. This is the first study to report the effect of VAC extract in Japanese patients.
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XUEXIANG CHANG, WENZHI ZHAO, and ZHIBIN HE
- Agricultural and forest meteorology (Print). 187:14-21
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Climatology, meteorology, Climatologie, météorologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Sciences du sol, Soil science, Physique, chimie, biochimie et biologie des sols agricoles et forestiers, Physics, chemistry, biochemistry and biology of agricultural and forest soils, Propriétés physiques, Physical properties, Dynamique de l'eau et des solutés (états et transfert), Water and solute dynamics, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Arbre forestier résineux, Softwood forest tree, Arbol forestal resinoso, Bassin hydrographique, Drainage basins, Cuenca hidrográfica, Caractéristique sol, Property of soil, Característica suelo, Coniferales, Gymnospermae, Propriété hydrique sol, Soil water properties, Propiedad hídrica, Propriété physique, Physical properties, Propiedad física, Spermatophyta, Aubier, Sapwood, Albura, Bassin fluvial, River basins, Cuenca fluvial, Biométéorologie, Biometeorology, Biometeorología, Ecoulement interne, Internal flow, Flujo interno, Facteur milieu, Environmental factor, Factor medio, Humidité sol, Soil moisture, Humedad suelo, Microclimat, Microclimate, Microclima, Milieu aride, Arid environment, Medio árido, Nord ouest, Northwest, Noroeste, Picea, Réponse, Response, Respuesta, Sève, Sap, Savia, Chine Nord Ouest, Qinghai, Environmental factors, Qinghai spruce, Radial pattern, Sap flow, and Upper Heihe River Basin
- Abstract
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In order to accurately estimate whole-tree water use and individual tree transpiration, it is important to have reliable information on radial patterns of sap velocity and responses of sap flow to local environmental conditions. Therefore, variation in sap flow and environmental conditions was investigated in a mature Qinghai spruce (Picea crassifolia) stands during the growing season of 2011 at the Pailougou watershed, in Qilianshan Mountain, located in the upper Heihe River Basin, in the arid region of North-west China. Daily sap flow was measured by the heat-pulse technique on nine trees during the growing season. It was found that the highest daily sap flow velocity in sap flow radial distribution was at 20 mm sapwood depth, and that from 10 mm to 20 mm sapwood depth, the daily sap flow velocity gradually increased, whereas from 20 mm to 40 mm sapwood depth, sap flow velocity gradually diminished. A simple Gaussian regression model for the radial distribution of sap flux velocity was formulated, which explained 92% of the radial profile variation of sap flow velocity. Sap flow velocity was heightened by increasing the global short-wave radiation (R, W m―2), vapour pressure deficit (D, kPa), and air temperature (T, °C) when R < 800 W m―2, D < 1.4 kPa, and T < 18.0 °C. It is, however, inherently difficult to establish firm relationships between sap flow velocity and R, D, and Tbecause of the complex crown environment. The correlation of daily sap flow velocity to soil moisture content on a clear day was fitted by a logistic regression. We conclude that measurement of radial flow pattern provides a reliable method of integrating sap flow from individual measuring points to the whole tree. And D, R, T and soil moisture had varying influences on sap flow velocity in the Qinghai Spruce.
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SHOUJIA SUN, PING MENG, JINSONG ZHANG, XIANCHONG WAN, NING ZHENG, and CHUNXIA HE
- Agricultural and forest meteorology (Print). 184:36-47
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Climatology, meteorology, Climatologie, météorologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Climatologie et météorologie agricoles et forestières, Agricultural and forest meteorology, Bilans et besoins hydriques. Evapotranspiration, Water balance and requirements. Evapotranspiration, Angiospermae, Arbre ornemental feuillu, Broadleaved ornamental tree, Arbol ornamental frondoso, Dicotyledones, Environnement physique, Physical environment, Medio ambiente físico, Fagaceae, Plante ligneuse, Woody plant, Planta leñosa, Plante ornementale, Ornamental crop, Planta ornamental, Spermatophyta, Biométéorologie, Biometeorology, Biometeorología, Composition isotopique, Isotopic composition, Composición isotópica, Evapotranspiration, Evapotranspiración, Isotope stable, Stable isotopes, Montagne, Mountain, Montaña, Nord, North, Norte, Partition, Partición, Partitionnement, Partitioning, Subdivisión, Perturbation, Perturbación, Régime permanent, Steady state, Régimen permanente, Région géographique, Geographical division, Región geografica, Zone forestière, Forest zone, Zona forestal, Forêt claire, Open woodland, Formación boscosa, Quercus variabilis, Foreign vapor, Keeling plot, Quercus variabilis Blum, and Stable isotope
- Abstract
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In terrestrial ecosystems, partitioning ecosystem-scale evapotranspiration (ET) between plant transpiration and soil evaporation remains a technical challenge. In this paper, we used a newly-developed laser-based isotope analyzer (OA-ICOS) and the Keeling plot approach to partition ET components of a Quercus variabilis plantation in a lithoid hilly area of north China. The results showed that, on day-of-year (DOY) 254, 257, and 263, the modeled leaf water 18O composition (δsL,b) and observed leaf water 18O composition (δL,b) were in substantial agreement and had a significant linear correlation with coefficient of 0.96, indicating that Keeling plot approach and Graig-Gorden model can be used in portioning ET between plant transpiration and soil evaporation in a terrestrial forest ecosystem. Isotopic partition revealed that the percent contribution of transpiration to total ET increased from the morning, reached maximum values at noon, with maximum values of 91.19%, 86.30%, and 85.37% for DOY 254, 257, and 263, respectively, indicating the transpiration from Q. variabilis Blum contributed the most to the total ET in this forest ecosystem. On DOY 260, the stability stratification was unstable, which resulted from the foreign vapor concentration. The increased vapor concentration led to a 80.83% difference between δsL,b and δL,b. The correlation coefficients between δsL,b and δL,b decreased from 0.96 to 0.43 when dataset on DOY 260 was included, indicating foreign vapor increased the uncertainty in the estimation of δ18O of ET (δET) and δ18O of transpiration (δT) in the forest ecosystem. Path analysis results suggested that water vapor concentration was the major factor influencing the partitioning of ET with isotopic approach in the forest ecosystem. Since the increased water vapor concentration and decreased atmosphere δ18O disturbed the estimation of δE, δT, δET, the isotopic approach cannot be used in partitioning ET under this condition on DOY 260. Therefore, under most circumstances the isotopic approach can be used to partition ET for forest ecosystem in a non-steady state (NSS), while water vapor concentration may cause uncertainties.
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HELMAN, David, LENSKY, Itamar M, MUSSERY, Amir, and LEU, Stefan
- Agricultural and forest meteorology (Print). 195-96:52-60
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Climatology, meteorology, Climatologie, météorologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Angiospermae, Caractéristique sol, Property of soil, Característica suelo, Dicotyledones, Leguminosae, Phénomène météorologique, Meteorological phenomenon, Fenómeno meteorológico, Plante ligneuse, Woody plant, Planta leñosa, Précipitation atmosphérique, Atmospheric precipitation, Precipitación atmosférica, Région géographique, Geographical division, Región geografica, Spermatophyta, Acacia, Biométéorologie, Biometeorology, Biometeorología, Fertilité sol, Soil fertility, Fertilidad suelo, Indice végétation, Vegetation index, Indice de vegetación, Milieu aride, Arid environment, Medio árido, Nutriment, Nutrient, Nutriente, Pluie, Rain, Lluvia, Productivité, Productivity, Productividad, Qualité sol, Soil quality, Calidad suelo, Zone forestière, Forest zone, Zona forestal, Désert Neguev, Effet à long terme, Long tem effect, Efecto a largo plazo, Neguev, Utilisation efficace, Efficient use, Uso eficaz, Acacia victoriae, MODIS, NDVI, Negev, Nutrients, and Rain use efficiency
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We evaluated the effects of Acacia victoriae islets planted in 1993 in the Negev drylands on the productivity of the native herbaceous vegetation and soil fertility. Biomass, mineral-P, N and K and soil organic matter were measured from the planted and an adjacent unplanted area. The satellite-derived Normalized Difference Vegetation Index (NDVI) from MODIS was used to expand the timespan of the analysis after calibration with field data. Results showed an average improvement in biomass and rain use efficiency (RUE) of 40% compared to the unplanted area. Improvement was also observed in all nutrients concentrations and organic matter. Biomass was highly related to precipitation (R2 = 0.90, p < 0.001), gradually declining from 2001 to 2009. Although declining with precipitation, RUE was maintained constantly higher in the planted area with respect to the unplanted lands even in dry years. The total biomass gained since plantation was estimated at 60 g m-2 yr-1 (i.e. 12 t ha-1) for a 20-year period. Our results suggest that planting woodland islets may significantly improve soil quality and biomass productivity of the native vegetation in drylands in a relatively short time.
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SON, N. T, CHEN, C. F, CHEN, C. R, MINH, V. Q, and TRUNG, N. H
- Agricultural and forest meteorology (Print). 197:52-64
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Climatology, meteorology, Climatologie, météorologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Angiospermae, Cours eau, Stream, Curso agua, Eau surface, Surface water, Agua superficie, Gramineae, Milieu aquatique, Aquatic environment, Medio acuático, Monocotyledones, Plante céréalière, Cereal crop, Planta cerealista, Région géographique, Geographical division, Región geografica, Spermatophyta, Type C3, C3-Type, Tipo C3, Végétal, Vegetals, Vegetal, Zone tropicale, Tropical zone, Zona tropical, Biométéorologie, Biometeorology, Biometeorología, Donnée, Data, Dato, Echelle grande, Large scale, Escala grande, Etude comparative, Comparative study, Estudio comparativo, Hydrologie, Hydrology, Hidrología, Indice végétation, Vegetation index, Indice de vegetación, Lissage, Smoothing, Alisamiento, Observation multitemporelle, Multidate observation, Observación multitemporal, Oryza sativa, Rendement, Yield, Rendimiento, Spectroradiométrie, Spectroradiometry, Espectroradiometría, Asie tropicale, Delta Mékong, Plante en C3, MODIS, Mekong River Delta, Rice crop, and Yield estimation
- Abstract
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Rice is one of the most important food crops worldwide, and large-scale rice yield estimation is thus critical for planners to formulate successful strategies to address food security and rice grain export issues. This study performed a comparative analysis of multitemporal Moderate Resolution Imaging Spectroradiometer (MODIS) enhanced vegetation index (EVI) and normalized difference index (NDVI) data for estimating rice crop yields in the Mekong River Delta (MRD), Vietnam. We processed the data for a 10-year period (2002-2011) following three main steps: (1) create a smooth time series of EVI and NDVI data, (2) formulate crop yield models, and (3) validate the model. The comparison results between EVI/NDVI-based estimated yields and the government's yield statistics indicated a significant relationship between the two datasets (p-value < 0.001). The estimated results produced from EVI-based models were slightly more accurate than those from NDVI-based models, with the correlation coefficients (R2) ranging from 0.62 to 0.71 for spring-winter and 0.4 to 0.56 for summer-autumn rice crops, respectively. The root mean square error (RMSE) and mean absolute error (MAE) used to measure the model accuracy revealed the consistency between EVI-based estimated yields and the government's yield statistics. The RMSE values for winter-spring and summer-autumn crops were, respectively, 6.9-8.1% and 5.4-6.7%, and MAE values were 5.4-6.7% and 6.5-9.5%. There was, however, a significant correlation between the estimated yields obtained from EVI- and NDVI-based models (p-value < 0.001), indicating no significant difference in the estimated yields between these two models. This study demonstrates advantages of using multitemporal MODIS EVI data for large-scale estimation of rice crop yields using the heading date in the MRD prior to the harvest period, and thus the methods could be transferable to other regions.
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HE, Zhi-Bin, YANG, Jun-Jun, JUN DU, ZHAO, Wen-Zhi, HU LIU, and CHANG, Xue-Xiang
- Agricultural and forest meteorology (Print). 188:58-63
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Climatology, meteorology, Climatologie, météorologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Arbre forestier résineux, Softwood forest tree, Arbol forestal resinoso, Coniferales, Environnement physique, Physical environment, Medio ambiente físico, Gymnospermae, Milieu aride, Arid environment, Medio árido, Spermatophyta, Zone climatique, Climatic zone, Zona climática, Biométéorologie, Biometeorology, Biometeorología, Canopée, Canopy(vegetation), Dosel, Forêt, Forests, Bosque, Interception, Intercepción, Montagne, Mountain, Montaña, Picea, Région géographique, Geographical division, Región geografica, Variabilité spatiale, Spatial variability, Variabilidad espacial, Zone semi aride, Semi arid zone, Zona semiárida, , Canopy interception, Semiarid mountain region, and Spruce forest
- Abstract
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Canopy interception has large spatial variability which complicates measurements and achievement of spatial representation. In the present study, we measured gross rainfall and throughfall from June 2011 to October 2012, and leaf area index (LAI), plant area index (PAI), and spatial locations of trees within Picea crassifolia forest in Qilian mountains of northwestern China. Spatial variability of canopy interception and related factors, and the minimum number and locations of collectors were analyzed by statistical techniques. The results show that spatial variation of canopy interception has a significant relationship with PAI, but not with LAI. This indicates that PAI is more appropriate parameters for a canopy interception model than LAI. Based on the relationship between canopy interception loss and PAI, the minimum number and locations of collectors were estimated. In this study, 10―12 collectors yielded representative throughfall in the forest, but these collectors required to be placed at the sites of mean values of PAI.
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OHTA, Takeshi, KOTANI, Ayumi, IIJIMA, Yoshihiro, MAXIMOV, Trofim C, ITO, Syogo, HANAMURA, Miho, KONONOV, Alexander V, and MAXIMOV, Ayal P
- Agricultural and forest meteorology (Print). 188:64-75
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Climatology, meteorology, Climatologie, météorologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Arbre forestier résineux, Softwood forest tree, Arbol forestal resinoso, Coniferales, Gymnospermae, Spermatophyta, Structure végétation, Vegetation structure, Estructura vegetación, Biométéorologie, Biometeorology, Biometeorología, Cycle carbone, Carbon cycle, Ciclo carbono, Dioxyde de carbone, Carbon dioxide, Carbono dióxido, Eau, Water, Agua, Echange gazeux, Gas exchange, Intercambio gaseoso, Engorgement sol, Waterlogging (soil), Anegamiento suelo, Etage dominant, Overstorey, Nivel dominante, Facteur milieu, Environmental factor, Factor medio, Forêt, Forests, Bosque, Larix sibirica, Sous étage, Understory, Subpiso, Stress, Estrés, Végétation, Vegetation, Vegetación, Eastern Siberia, Overstory vegetation, Understory vegetation, Water and carbon exchanges, and Wet stress
- Abstract
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Water vapour and carbon dioxide fluxes, as well as environmental factors, were measured in an Eastern Siberian larch forest for 14 years from 1998 to 2011 to understand the water and carbon balances and the effects of environmental variables on these balances in this region. The overstory vegetation in this forest has been damaged by the unusual waterlogging that has occurred since 2005, and the number of living larch decreased by 15% from 1998 to 2011. During this period, the composition of floor vegetation changed from dense cowberry to grasses and shrubs with high water tolerance. This period was categorized into three phases according to annual precipitation: normal years from 1998 to 2000 and from 2009 to 2011, dry years from 2001 to 2004, and wet years from 2005 to 2008. Although the time series of atmospheric conditions were independent of that of annual precipitation, the behaviour of underground conditions such as soil temperature and soil water content followed the change in annual precipitation. The relationships of the evapotranspiration ratio and surface conductance to soil water content from 2007 were different from those prior to 2006, and the group from 2007 was smaller than that prior to 2006 for both relationships. The relationship between gross primary production and soil water content also changed, but this change occurred in 2008. Specifically, the change in characteristics of evapotranspiration preceded that in carbon dioxide by almost one year. The main driver of the interannual variation in water use efficiency was variation in evapotranspiration until 2007 but was variation in gross primary production since 2008. The time lag of the response of evapotranspiration to increased soil water content was nearly two years, whereas it was about three years in the case of gross primary production. Although drought stresses on forests are well known, this is the first report of water and carbon exchanges in Eastern Siberia indicating that the boreal forest has been damaged by wet stresses at the interannual scale.
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JING WANG, ENLI WANG, HONG YIN, LIPING FENG, and JIANPING ZHANG
- Agricultural and forest meteorology (Print). 195-96:89-101
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Climatology, meteorology, Climatologie, météorologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Génétique et amélioration des plantes d'intérêt économique, Genetics and breeding of economic plants, Angiospermae, Climatologie dynamique, Dynamical climatology, Climatología dinámica, Gramineae, Milieu aride, Arid environment, Medio árido, Modèle simulation, Simulation model, Modelo simulación, Monocotyledones, Plante céréalière, Cereal crop, Planta cerealista, Spermatophyta, Sélection dirigée, Artificial selection, Selección dirigida, Sélection génétique, Genetic selection, Selección genética, Type C4, C4-Type, Tipo C4, Végétal, Vegetals, Vegetal, Zone climatique, Climatic zone, Zona climática, Zone tempérée, Temperate zone, Zona temperada, Biométéorologie, Biometeorology, Biometeorología, Changement climatique, Climate change, Cambio climático, Changement global, Global change, Cambio global, Cultivar, Densité plantation, Planting density, Densidad plantación, Nord, North, Norte, Plaine alluviale, Alluvial plain, Llanura aluvial, Rendement, Yield, Rendimiento, Ressource alimentaire, Food supply, Recurso alimentario, Réchauffement, Warming, Calefacción, Région géographique, Geographical division, Región geografica, Simulation ordinateur, Computer simulation, Simulación computadora, Sécurité alimentaire, Food security, Seguridad alimentaria, Sélection variétale, Varietal selection, Selección varietal, Zea mays, Zone semi aride, Semi arid zone, Zona semiárida, Ecart de rendement, Yield gap, Intervalo de rendimiento, Modèle APSIM, Plaine de Chine du Nord, North China Plain, Llano de China del norte, Plante en C4, APSIM, Cultivar selection, and Global warming and dimming
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Quantifying the changes in crop potential yields and yield gaps is essential to determine the yield-contributing and yield-limiting factors and enhance crop productivity. Here we combine simulation modeling and long-term maize yield records (1981-2009) from 10 sites to investigate the changes in maize yield potential, actual yield and yield gaps in the past three decades in the North China Plain (NCP). The cultivar parameters in the APSIM-maize model were derived based on the recorded flowering and maturity dates at each site, and the simulation results of calibrated model was able to explain >63% of the variations in recorded maize grain yield across the 10 sites. Potential maize yield simulated under sufficient water and nitrogen supply showed a general declining trend, significantly (P<0.01) at half of the study sites. This was mainly caused by the declining radiation together with increasing temperature, particularly during the pre-flowering period. Continuous adoptions of new maize varieties helped to maintain the pre-flowering periods at some sites and to extend post-flowering periods at most sites. This, together with increasing planting density, led to continuous increase in maize yields. As a result, maize yield gaps continued to shrink (P< 0.05) at all the sites except for Zhengzhou, with a rate ranging from -116.8 kg/ha a to -356.5 kg/ha a across sites. At two of the studied sites, the maize potential yield had already been achieved. While application of irrigation and nitrogen fertilizers has been managed at near optimal level already, other new technological breakthroughs will be needed for future advance of maize yield.
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12. Responses of wheat growth and yield to climate change in different climate zones of China, 1981-2009 [2014]
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FULU TAO, ZHAO ZHANG, DENGPAN XIAO, SHUAI ZHANG, RÖTTER, Reimund P, WENJIAO SHI, YUJIE LIU, MENG WANG, FENGSHAN LIU, and HE ZHANG
- Agricultural and forest meteorology (Print). 189-190:91-104
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Climatology, meteorology, Climatologie, météorologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Angiospermae, Climatologie dynamique, Dynamical climatology, Climatología dinámica, Gramineae, Monocotyledones, Spermatophyta, Type C3, C3-Type, Tipo C3, Végétal, Vegetals, Vegetal, Agriculture, Agricultura, Biométéorologie, Biometeorology, Biometeorología, Changement climatique, Climate change, Cambio climático, Croissance, Growth, Crecimiento, Phénologie, Phenology, Fenología, Rendement, Yield, Rendimiento, Réponse, Response, Respuesta, Triticum, Zone climatique, Climatic zone, Zona climática, , Plante en C3, Crop, and Impact and adaptation
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The experiment observations at 120 agricultural meteorological stations spanning from 1981 to 2009 across China were used to accelerate understandings of the response of wheat growth and productivity to climate change in different climate zones, with panel regression models. We found climate during wheat growth period had changed significantly during 1981―2009, and the change had caused measurable impacts on wheat growth and yield in most of the zones. Wheat anthesis date and maturity date advanced significantly, and the lengths of growth period before anthesis and whole growth period were significantly shortened, however the length of reproductive growth period was significantly prolonged despite of the negative impacts of temperature increase. The increasing adoption of cultivars with longer reproductive growth period offset the negative impacts of climate change and increased yield. Changes in temperature, precipitation and solar radiation in the past three decades jointly increased wheat yield in northern China by 0.9―12.9%, however reduced wheat yield in southern China by 1.2―10.2%, with a large spatial difference. Our studies better represented crop system dynamics using detailed phenological records, consequently better accounted for adaptations such as shifts in sowing date and crop cultivars photo-thermal traits when quantifying climate impacts on wheat yield. Our findings suggest the response of wheat growth and yield to climate change is underway in China. The changes in crop system dynamics and cultivars traits have to be sufficiently taken into account to improve the prediction of climate impacts and to plan adaptations for future.
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GUOFU YUAN, PEI ZHANG, SHAO, Ming-An, YI LUO, and XUCHAO ZHU
- Agricultural and forest meteorology (Print). 194:144-154
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Climatology, meteorology, Climatologie, météorologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Climatologie et météorologie agricoles et forestières, Agricultural and forest meteorology, Bilans et besoins hydriques. Evapotranspiration, Water balance and requirements. Evapotranspiration, Angiospermae, Bassin hydrographique, Drainage basins, Cuenca hidrográfica, Cours eau, Stream, Curso agua, Dicotyledones, Eau surface, Surface water, Agua superficie, Milieu aquatique, Aquatic environment, Medio acuático, Méthode statistique, Statistical method, Método estadístico, Plante ligneuse, Woody plant, Planta leñosa, Spermatophyta, Tamaricaceae, Zone tempérée, Temperate zone, Zona temperada, Bassin fluvial, River basins, Cuenca fluvial, Biométéorologie, Biometeorology, Biometeorología, Climat aride, Arid climate, Clima árido, Echange hydrique, Hydric exchange, Intercambio hídrico, Energie, Energy, Energía, Evapotranspiration, Evapotranspiración, Hydrologie, Hydrology, Hidrología, Milieu aride, Arid environment, Medio árido, Méthode covariance turbulence, Eddy covariance method, Método covariancia turbulencia, Ripicole, Riparian, Ripicola, Rivière, Rivers, Río, Tamarix, Transfert énergie, Energy transfer, Transferencia energía, Bassin Tarim, Chine Nord Ouest, Xinjiang, Eddy covariance, Hyper-arid, Tamarix spp, Tarim River, and Water and energy exchange
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Determining the maintenance and control mechanisms of the energy and water exchanges over the desert riparian forest zone in the lower Tarim River of China could improve our understanding of land surface processes of the groundwater-dependent ecosystems in the hinterland area of the Eurasian continent under hyper-arid climate. Nearly three years of continuous measurements of meteorological factors, surface water and energy fluxes, soil water content, and groundwater table were carried out over a riparian Tamarix spp. stand in the lower Tarim River basin. Because of scarce precipitation and low air humidity, the diurnal and seasonal variations of most meteorological factors exhibited simple unimodal dynamics. However, the seasonal variation of latent heat exchange (LE) was distinctly related to plant phenology. The sensible heat exchange (H) exhibited reverse course with the LE seasonal course, which suggested seasonal variation of the H was controlled by the LE course. In the daytime, a good linear relationship existed between evapotranspiration (ET) and reference evapotranspiration. The yearly ET over the tamarisk stand was approximately 500 mm year-1, and the mean daily ET is about 3.85 mm d-1 in a vibrant growing season. The groundwater table and the soil water content (SWC) near the groundwater table exhibited obvious seasonal and diurnal variations in the growing seasons but SWC in the shallow soil layer did not, suggesting the groundwater was the water source of the tamarisk. Our analysis indicated that under a hyper-arid climate, the energy and water exchanges over riparian tamarisk stands in the lower Tarim River basin showed certain features: (1) plant transpiration accounted for most of the surface ET, with soil evaporation weak and negligible; (2) the seasonal processes of surface energy and water exchanges were highly related with plant phenology; (3) the diurnal processes of ET resulted from the comprehensive effects of all atmospheric factors; and (4) ET depends on groundwater, rather than precipitation.
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MUNZ, Sebastian, FEIKE, Til, QING CHEN, CLAUPEIN, Wilhelm, and GRAEFF-HÖNNINGER, Simone
- Agricultural and forest meteorology (Print). 195-96:152-164
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Climatology, meteorology, Climatologie, météorologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Systèmes de culture. Pratiques culturales. Travail du sol, Cropping systems. Cultivation. Soil tillage, Généralités. Systèmes et modes de culture, Generalities. Cropping systems and patterns, Génétique et amélioration des plantes d'intérêt économique, Genetics and breeding of economic plants, Angiospermae, Gramineae, Milieu aride, Arid environment, Medio árido, Monocotyledones, Plante céréalière, Cereal crop, Planta cerealista, Spermatophyta, Type C4, C4-Type, Tipo C4, Végétal, Vegetals, Vegetal, Zone climatique, Climatic zone, Zona climática, Zone tempérée, Temperate zone, Zona temperada, Biométéorologie, Biometeorology, Biometeorología, Cultivar, Culture intercalaire, Intercropping, Cultivo intercalado, Environnement, Environment, Medio ambiente, Interaction, Interacción, Nord, North, Norte, Plaine alluviale, Alluvial plain, Llanura aluvial, Région géographique, Geographical division, Región geografica, Système culture, Cropping system, Sistema cultural, Transmission lumière, Light transmission, Transmisión luz, Zea mays, Zone semi aride, Semi arid zone, Zona semiárida, Plaine de Chine du Nord, North China Plain, Llano de China del norte, Plante en C4, Maize, and Strip width
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Strip-intercropping systems combine the possibility to increase productivity and resource-use-efficiency with the facilitation to accommodate machinery. In strip-intercropping systems with maize, competition for light strongly influences the total productivity. Therefore, we studied plant growth and yield formation in maize grown in strips with a neighboring, shorter crop (e.g. bush bean) over three growing seasons in the North China Plain (NCP) with irrigation and over four growing seasons in south-western Germany without irrigation. The chosen locations represented different latitudes, weather, and management conditions. Based on these data, interactions between the local environment, mainly radiation and water availability, and the planted maize cultivars were investigated. Further, a light partitioning model was used to study the effect of strip width, maize canopy height and leaf area index (LAI), latitude, and sky conditions on the light availability across the strip of bush bean over the co-growing period with maize. Experimental results showed an increase of maize yield in border rows in years with sufficient water supply. On average, maize yields calculated for strips consisting of 18 to four rows showed an increase by 3 to 12% at the German and 5 to 24% at the Chinese sites, respectively. Among the three cultivars included in this study, yield in border rows increased mainly by a larger number of kernels per plant. Those were achieved by a larger number of ears per plant in the German cultivars and by larger number of kernels per ear in the Chinese cultivar, respectively. Simulations of the light availability across the strip of the neighboring, shorter bush bean crop indicated that increasing the strip width might only reduce shading in the border rows when the bush bean is grown at lower latitudes under a high fraction of direct radiation. When grown at higher latitudes, the selection of a maize cultivar with reduced height and LAI are suitable options to increase the light availability for the shorter crop. However, shade levels in the border rows of the shorter crop remain high at around 25%. For the future improvement of the productivity of strip-intercropping systems, the selection of suitable maize cultivars and shade-tolerant cultivars and species will be decisive. .
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XUEXIANG CHANG, WENZHI ZHAO, HU LIU, XIAO WEI, BING LIU, and ZHIBIN HE
- Agricultural and forest meteorology (Print). 198-199:209-220
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Climatology, meteorology, Climatologie, météorologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Arbre forestier résineux, Softwood forest tree, Arbol forestal resinoso, Bassin hydrographique, Drainage basins, Cuenca hidrográfica, Coniferales, Gymnospermae, Spermatophyta, Bassin fluvial, River basins, Cuenca fluvial, Biométéorologie, Biometeorology, Biometeorología, Canopée, Canopy(vegetation), Dosel, Ecoulement interne, Internal flow, Flujo interno, Forêt, Forests, Bosque, Milieu aride, Arid environment, Medio árido, Nord ouest, Northwest, Noroeste, Picea, Sève, Sap, Savia, Transpiration, Transpiración, , Augmentation échelle, Scaling-up, Aumento de escala, Chine Nord Ouest, Qinghai, Canopy conductance, Picea crassifolia, Sap flow, and Upper Heihe River Basin
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Tree transpiration plays a determining role in the water balance of forest stands and in water yields from forested catchments, especially in arid regions. This study describes direct measurements of tree sap flow by heat pulse velocity method, and calculations of stand transpiration and canopy conductance, during the 2011 and 2012 growing seasons, in an 80- to 120-year-old Picea crassifolia stand in a natural forest. The experiment was carried out on Qilianshan Mountain, located in the upper Heihe River Basin, in the arid region of Northwest China. It was found that stand transpiration (Ec) ranged from 1.0 mm d-1 to 2.4 mmd-1, and from 1.2 mmd-1 to 2.4 mm d-1, during the 2011 and 2012 growing seasons, respectively. Total Ec was 195.2 mm, 219.6 mm during the 2011 and 2012 growing seasons, respectively. And total Ec during the 2012 growing season was 12.5% higher than during the 2011 growing season. Based on the half-hourly temporal scale, canopy conductance was between 0.3 mm S-1 and 51.3 mm S-1 , and between 1.2 and 57.0 mm s-1, during the 2011 and 2012 growing seasons, respectively. Canopy conductance was sensitive to variations in climatic variables such as vapor pressure deficit (D), air temperature (T), wind speed (W) and global short-wave radiation (R). It is also evident that an exponential decay function, including D and T, accounted for 81 % and 19% of the variations in canopy conductance, respectively. These results was not only providing the basis for more detailed analyses of water physiology and growth of Qinghai spruce trees for the later application of a climate-driven process model, but also might have implications for forest management in Qilianshan Mountains.
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WANG SHIPING, WANG CHANGSHUN, DUAN JICHUANG, ZHU XIAOXUE, XU GUANGPING, LUO CAIYUN, ZHANG ZHENHUA, MENG FANDONG, LI YINGNIAN, and DU MINGYUAN
- Agricultural and forest meteorology (Print). 189-190:220-228
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Climatology, meteorology, Climatologie, météorologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Climatologie dynamique, Dynamical climatology, Climatología dinámica, Saison, Season, Estación, Spermatophyta, Angiospermae, Biométéorologie, Biometeorology, Biometeorología, Changement climatique, Climate change, Cambio climático, Date, Fecha, Durée, Duration, Duración, Eté, Summer, Verano, Floraison, Flowering, Floración, Gradient vertical, Vertical gradient, Gradiente vertical, Phénologie, Phenology, Fenología, Printemps, Spring(season), Primavera, Précocité, Earliness, Precocidad, Timing, Végétation alpine, Alpine vegetation, Vegetación alpina, Choix de la date, Elección de la época, Plateau tibétain, Tibetan Plateau, Alpine plants, Early-spring flowering plants, Evolutionary adaptation, Mid-summer flowering plants, and Reproductive phenology
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Previous studies have focused on the effects of increased temperatures on a single green-up and/or flowering event, but less is known about how acceleration of spring phenology may change subsequent phenological events. We present results of a field experiment to test the hypotheses that (1) the timing of phenological events does not necessarily delay as elevation increases; (2) changes in the timing of a sequence of phenological events will be consistent for all phenological events along the elevation gradient; and thus (3) change in the timing of phenological events does not affect the duration of the entire reproductive stage in the alpine region. The experiment was conducted along an elevation gradient from 3200 to 3800 m using two early-spring flowering (ESF) sedges and four mid-summer flowering (MSF) plants (two forbs and two grasses). Generally, our results only supported the first hypothesis. Lower elevation delayed the starting dates of all phenological events for ESF plants at 3200 m compared with other elevations, whereas the opposite trend was observed for MSF-grasses. MSF-forbs had the earliest leaf-out at 3200 m and the earliest first flowering at 3600 m, and onset of fruit-set advanced with increasing elevation. The entire reproductive duration was shortened with increasing elevation for MSF-forbs, whereas it was the shortest for ESF at 3600 m and for MSF-grasses at 3200 and/or 3800 m. Individual reproductive stages had independent responses to climate change. The duration of the entire growing season for ESF plants decreased as elevation increased. For MSF-forbs, it was longest at 3200 m and shortest at 3400 m, while for MSF-grasses it was shortest at 3200 m and at 3800 m. Reproduction was compressed into shorter time periods only for MSF-forbs at 3600 and 3800 m. Therefore, reproduction is not tightly integrated across the life cycle, and earlier reproductive development induced by warmer spring temperatures did not consistently advance flowering and fruiting times and their durations for the alpine plants studied. The effects of climate change on the timing and duration of phenological events were species-specific. Selection for changes in the timing and duration of individual phenological stages in response to climate change due to evolutionary adaptation should be taken into account.
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17. Spatio-temporal variation in phenological response of citrus to climate change in Iran: 1960-2010 [2014]
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FITCHETT, J. M, GRAB, S. W, THOMPSON, D. I, and ROSHAN, G
- Agricultural and forest meteorology (Print). 198-199:285-293
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Climatology, meteorology, Climatologie, météorologie, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Agrume, Citrus fruit, Agrios, Angiospermae, Climatologie dynamique, Dynamical climatology, Climatología dinámica, Dicotyledones, Rutaceae, Siècle 21eme, Century 21st, Siglo 21, Spermatophyta, Biométéorologie, Biometeorology, Biometeorología, Changement climatique, Climate change, Cambio climático, Citrus, Climat, Climate, Clima, Environnement physique, Physical environment, Medio ambiente físico, Floraison, Flowering, Floración, Hybride, Hybrid, Híbrido, Phénologie, Phenology, Fenología, Réponse, Response, Respuesta, Température, Temperature, Temperatura, Variation temporelle, Time variation, Variación temporal, Asie du Sud-Ouest, Epoque contemporaine, Citrus hybrids, Climate trends, Peak flowering, Phenological advance and delay, and Precipitation
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Recent studies investigating floral and faunal phenological responses to climate change have highlighted the extent to which these relationships are species and location specific. This study investigates temporal responses of citrus peak flowering to climate change in the cities of Kerman, Shiraz and Gorgan, Iran. Phenological data comprise peak flowering dates of five citrus types: orange, tangerine, sweet lemon, sour lemon and sour orange, collected daily from government heritage gardens located within each of the cities over the period 1960-2010. For the same period, daily Tmax, Tmin and rainfall data were acquired from the Iranian Meteorological Organization. Time trend analyses were undertaken for both the phenological and meteorological data, followed by linear regression to determine the nature and extent of relationships between these variables. We find that the mean peak flowering dates, and their long-term trends over the 51 -year period, are similar across the five citrus types within each city, but demonstrate significant differences between cities. Flowering date advances of 0.12-0.17d/yr are recorded for Kerman, and more rapid advances of 0.56-0.65 d/yr for Shiraz. Notably, progressive delays in flowering dates occur in Gorgan (0.05-0.1 d/yr). The peak flowering dates in the former two cities demonstrate strong relationships with mean annual Tmin, ranging from r=0.47-0.61 (p = 0.0045; p< 0.0001) for Kerman to r= 0.53-0.67 (p = 0.0386; p < 0.0001) for Shiraz, and equate to peak flowering advances of 3.15-3.39 d/°C and 4.34-5.47 d/°C, respectively. By contrast, the strongest relationships between peak flowering dates and annual climate in Gorgan are with rainfall (r= 0.02-0.3, p=0.8874; p=0.0528), indicating a weak phenophase response of 0.01 d/mm. For Gorgan, the strongest relationships (r=0.43-075, p = 0.0002 to p < 0.0001) are between peak flowering date and mean Tmax for May, the month during which peak flowering occurs, with a delay in flowering of 1.26-1.86 d/°C cooling. This suggests a relatively more influential climatic role directly preceding peak flowering, which may be associated with anomalous cooling in May. However, Kerman and Shiraz demonstrate more consistent strength in correlation between peak flowering and climate variables across the months of the year, with only slight peaks for the months flanking peak flowering. Our study highlights the importance of considering location-specific phenophase shifts within given regions, as dissimilar trends may occur within a country; this has important implications for future agricultural planning and fruit crop supply to local and international markets.
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FAN JUN, GAO YU, WANG QUANJIU, MALHI, Sukhdev S, and LI YANGYANG
- Agricultural water management (Print). 138:10-16
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Hydrology, water resources, Hydrologie, ressources en eau, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Sciences du sol, Soil science, Physique, chimie, biochimie et biologie des sols agricoles et forestiers, Physics, chemistry, biochemistry and biology of agricultural and forest soils, Propriétés physiques, Physical properties, Dynamique de l'eau et des solutés (états et transfert), Water and solute dynamics, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Aménagement sol, Soil management, Acondicionamiento suelo, Angiospermae, Caractéristique sol, Property of soil, Característica suelo, Condition thermique, Thermal condition, Condición térmica, Dicotyledones, Environnement physique, Physical environment, Medio ambiente físico, Leguminosae, Propriété hydrique sol, Soil water properties, Propiedad hídrica, Propriété physique, Physical properties, Propiedad física, Propriété thermique, Thermal properties, Propiedad térmica, Spermatophyta, Sédiment, Sediments, Sedimento, Type C3, C3-Type, Tipo C3, Végétal, Vegetals, Vegetal, Aménagement hydraulique, Water engineering, Aprovechamiento hidráulico, Gravier, Gravel, Ripio, Humidité sol, Soil moisture, Humedad suelo, Loess, Medicago sativa, Nord ouest, Northwest, Noroeste, Paillage, Mulching, Cobertura vegetal, Paille, Straw, Paja, Plante fourragère, Fodder crop, Planta forrajera, Rendement, Yield, Rendimiento, Sol, Soils, Suelo, Température sol, Soil temperature, Temperatura suelo, Plante en C3, Roche clastique meuble, Stockage eau, Water storage, Almacenamiento agua, Forage yield, Gravel mulch, Loess Plateau, Soil water, and Straw mulch
- Abstract
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In the dryland region of the Loess Plateau of northern China, alfalfa (Medicago sativa L.) is widely grown for animal feed to develop livestock operations, while also reducing soil erosion and improving soil fertility/quality. A field experiment was carried out on a sandy loam soil from April 2007 to October 2012 to evaluate the processes of soil desiccation in the 500cm soil profiles, and the effects of mulch management on soil water content and temperature in the upper soil layer (5-15 cm), water use efficiency (WUE) and forage dry matter yield (DMY) of alfalfa in rainfed pasture land. Three treatments were: no mulch control, gravel mulch and corn straw mulch. Corn straw and gravel were chosen, because these materials can be obtained easily in this region. Soil depth of water uptake by alfalfa moved down to deep soil quickly and seasonal rainfall became the main contributing factor after 5 years. The presence of straw on the soil surface reduced the maximum temperature, but it increased the minimum diurnal soil temperature. Straw mulch was more effective in regulating soil temperature than gravel in the pasture planting. Straw mulch and gravel mulch both enhanced soil water content at the 15 cm depth. Straw mulch increased forage DMY of alfalfa by 420 kg ha-1 (by 6.7%) compared to no mulch control over the four growing seasons from 2009 to 2012, and gravel mulch reduced the forage DMY by 36 kg ha-1 (by 0.5%) during that period, but effects were not significant statistically. Straw mulch increased concentration of nitrate-N and available P in the upper soil layer significantly, and improved WUE. In conclusion, the findings suggest that alfalfa could extract water from progressively deeper soil layers and straw mulch was effective in minimizing fluctuations in soil temperature, and increasing water storage in surface shallow soil layers, forage yield and water use efficiency of alfalfa. Mulching grass hedges intercropping or contour hedgerow intercropping should be considered on sloping land.
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ZHEN WANG, JIUSHENG LI, and YANFENG LI
- Agricultural water management (Print). 142:19-28
- Subjects
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Hydrology, water resources, Hydrologie, ressources en eau, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Angiospermae, Anion minéral, Inorganic anion, Anión inorgánico, Anion monovalent, Monovalent anion, Anión monovalente, Azote minéral, Inorganic nitrogen, Nitrógeno inorgánico, Composé de l'azote, Nitrogen compounds, Compuesto nitrogenado, Elément minéral, Inorganic element, Elemento inorgánico, Gramineae, Ion minéral, Inorganic ion, Ión inorgánico, Macroélément, Macronutrient(mineral), Elemento primario, Milieu aride, Arid environment, Medio árido, Monocotyledones, Plante céréalière, Cereal crop, Planta cerealista, Spermatophyta, Type C4, C4-Type, Tipo C4, Végétal, Vegetals, Vegetal, Zone climatique, Climatic zone, Zona climática, Zone tempérée, Temperate zone, Zona temperada, Aménagement hydraulique, Water engineering, Aprovechamiento hidráulico, Irrigation fertilisante, Fertigation, Riego fertilizante, Lixiviation souterraine, Underground leaching, Lixiviación subterránea, Microirrigation, Microriego, Nitrate, Nitrates, Nitrato, Nord, North, Norte, Percolation, Percolación, Plaine alluviale, Alluvial plain, Llanura aluvial, Période végétation, Growing season, Período de crecimiento, Région géographique, Geographical division, Región geografica, Simulation, Simulación, Système, System, Sistema, Uniformité, Uniformity, Uniformidad, Zea mays, Zone semi aride, Semi arid zone, Zona semiárida, Plaine de Chine du Nord, North China Plain, Llano de China del norte, Plante en C4, Deep percolation, and HYDRUS-2D
- Abstract
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Drip irrigation has been recognized as an efficient irrigation method to improve water and nitrogen use efficiency. However, less-than-optimum management of drip system may cause deep percolation and nitrate leaching. The effects of drip system uniformity and precipitation on deep percolation and nitrate leaching under maize in a subhumid region were evaluated using a water and solute transport model HYDRUS-2D. Field experiment data on the spatial and temporal distribution of water and nitrate content during the growing seasons (2011 and 2012) of maize were collected to calibrate and validate the model. The validation indicated that the model performed well with an RMSE (root mean square error) value of 0.03-0.05 cm3 cm-3 for soil water content and 2.6-8.9 mg kg-1 for nitrate content during the growing season. Then, deep percolation and nitrate leaching were simulated under varying drip system uniformities and precipitation patterns. In the simulations, three Christiansen uniformity coefficients (CU) of 60%, 80%, and 95% were tested under typical precipitation patterns of dry, normal, and wet growing seasons that were determined from 32 years (1980-2011) of meteorological data. The result demonstrated that deep percolation and nitrate leaching most likely occurred following a heavy precipitation event, whereas slight deep percolation was observed following an irrigation event. The averaged seasonal nitrate leaching over the three drip system uniformities was 34.1 kg ha-1 for dry growing seasons (precipitation less than 287 mm), 60.3 kg ha-1 for normal seasons (precipitation from 287 to 480 mm), and 109.3 kg ha-1 for the wet seasons (precipitation greater than 480 mm). Drip system uniformity had a more significant effect on nitrate leaching during dry seasons than during normal and wet seasons. A correlation analysis between seasonal nitrate leaching and precipitation, irrigation, and drip system uniformity revealed that it was most significantly affected by seasonal rainfall, followed by system uniformity. Both the amount of precipitation and the temporal distribution of precipitation during the growing season of crop should therefore be considered when the target drip irrigation uniformity is determined.
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DIANYU CHEN, YOUKE WANG, SHOUYANG LIU, XINGUANG WEI, and XING WANG
- Agricultural water management (Print). 136:23-33
- Subjects
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Agronomy, agriculture, phytopathology, Agronomie, agriculture, phytopathologie, Environment, Environnement, Forestry, silviculture, Foresterie, sylviculture, Hydrology, water resources, Hydrologie, ressources en eau, Sciences biologiques et medicales, Biological and medical sciences, Sciences biologiques fondamentales et appliquees. Psychologie, Fundamental and applied biological sciences. Psychology, Agronomie. Sciences du sol et productions vegetales, Agronomy. Soil science and plant productions, Sciences du sol, Soil science, Physique, chimie, biochimie et biologie des sols agricoles et forestiers, Physics, chemistry, biochemistry and biology of agricultural and forest soils, Propriétés physiques, Physical properties, Dynamique de l'eau et des solutés (états et transfert), Water and solute dynamics, Agronomie générale. Phytotechnie, General agronomy. Plant production, Climatologie et météorologie agricoles et forestières. Irrigation. Drainage, Agricultural and forest climatology and meteorology. Irrigation. Drainage, Angiospermae, Arbre fruitier, Fruit tree, Arbol frutal, Caractéristique sol, Property of soil, Característica suelo, Dicotyledones, Environnement physique, Physical environment, Medio ambiente físico, Facteur milieu, Environmental factor, Factor medio, Milieu aride, Arid environment, Medio árido, Plante fruitière, Fruit crop, Planta frutal, Propriété hydrique sol, Soil water properties, Propiedad hídrica, Propriété physique, Physical properties, Propiedad física, Rhamnaceae, Spermatophyta, Végétal, Vegetals, Vegetal, Xérophyte, Xerophyte, Xerófito, Zone climatique, Climatic zone, Zona climática, Aménagement hydraulique, Water engineering, Aprovechamiento hidráulico, Condition météorologique, Atmospheric condition, Condición meteorológica, Ecoulement interne, Internal flow, Flujo interno, Facteur édaphique, Edaphic factor, Factor edáfico, Humidité sol, Soil moisture, Humedad suelo, Nord ouest, Northwest, Noroeste, Réponse, Response, Respuesta, Sève, Sap, Savia, Ziziphus jujuba, Zone semi aride, Semi arid zone, Zona semiárida, Plantations, Plantationes, Meteorological factor, Rainfed jujube plantation, Relative sap flow, and Semiarid region
- Abstract
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As a drought tolerant plant, jujube (Ziziphus jujuba Mill.) is commonly planted in semiarid Northwest China under rainfed conditions. To clarify the response of water use to climatic conditions, sap flow (SF) in 8 non-irrigated jujube trees was monitored using thermal dissipation probes. Also meteorological variables, soil water content, crown projection area and leaf area index were measured during the 2012 growth season. Based on relative extractable water (θe), soil moisture conditions were classified into water stress (θe < 0.4) and non-water stress (θe > 0.4) conditions. Since leaf area (LA) significantly influences SF, relative sap flow (defined as SFR = SF/LA) was used to analyze its relationships with selected meteorological factors. Obvious differences were noted between responses of SFR and its sensitivity to meteorological factors under the two different soil moisture conditions. Daily SFR was linearly related with solar radiation (Rs) but logarithmically related with vapor pressure deficit (VPD), variable of transpiration (VT) and reference crop evapotranspiration under both soil moisture conditions. Hourly SFR was linearly related with Rs, VPD and VT at θe>0.4, while, at θe< 0.4, it was lineary related with these variables to a threshold value, but it tracked a horizontal curve thereafter. On the average, the change in SFR with meteorological factors was classified into two on the basis of the time of day. The first characteristic change was during 00:00-15:00 h and the second during the rest of the day. There were significant differences in SFR dynamics between the two periods of the day under every soil moisture conditions, while, significant differences in the first periods but few differences in the second periods of SFR dynamics between two soil moisture conditions. The results of the study could be used to fine-tune transpiration modeling for efficient soil water management in rainfed jujube plantations in semiarid regions.
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