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排序方式: 共有418条查询结果,搜索用时 31 毫秒
61.
Golnaz Badr Gerrit Hoogenboom Michelle Moyer Markus Keller Richard Rupp Joan Davenport 《Precision Agriculture》2018,19(6):1027-1048
Developing a sustainable agricultural production system requires knowledge of the climate, soil, and topography of the area of interest. This is especially relevant for wine grape (Vitis vinefera L.) production. The main objective of this study was the development of a comprehensive system to aid in the selection of suitable areas for grapevine cultivation. Included in this system were several bioclimatic indices, such as Growing Degree Days (GDD), Frost Free Days (FFD), and the Huglin Index (HI) calculated over a period of 30 years using daily weather data obtained from the University of Idaho’s Gridded Surface Meteorological (UI GSM) dataset. Soil data and topographical data were also included in the system. The bioclimatic indices, soil, and topographic data were then transformed using fuzzy logic, and suitability maps with scores ranging from 0 to 1 were developed. The final vineyard-potential scores were obtained by combining the soil, weather, and topographic potential scores with a range from 0 to 1, where 0 pertained to non-suitable areas and 1 referred to optimal sites. The maps were evaluated by comparing the range of suitability scores of existing vineyards in Washington State. The evaluation indicated that 97% of the established vineyards have a vineyard-potential score that ranges from 0.8 to 1. The results of this study revealed that 11% of the total study area had a high potential for wine grape production. This study was able to successfully employ fuzzy logic to help decision-makers, growers, and others with conducting a precise land assessment for wine grape production. 相似文献
62.
The orchestrated migration of T lymphocytes is important for generating immunity and maintaining immunological tolerance. T lymphocytes can be divided into two populations, αβ T cells and γδ T cells, on the basis of their expression of different forms of the T cell receptor (TCR). γδ T cells represent an innate subset of T lymphocytes that play an important role in early immune response against a variety of pathogens, including bacteria and viruses. γδ T cells are abundant in the epithelial tissues. In ruminants and pigs, they constitute a major proportion of the blood lymphocyte pool, unlike in rodents and humans. Although recent studies using large animals have suggested that epithelial γδ T cells are the major source of γδ T cells in peripheral blood, and that they recirculate between epithelial tissues and blood via lymphatics, the migration pattern of these cells is largely unknown. The aim of this review is to provide an overview of the current knowledge on γδ T cell migration under steady-state conditions. A deeper understanding of γδ T cell migration may enable therapeutic modulation of innate immune responses. 相似文献
63.
Colaço André F. Molin José P. Rosell-Polo Joan R. Escolà Alexandre 《Precision Agriculture》2019,20(4):805-822
Precision Agriculture - Site-specific management strategies are usually dependant on the understanding of the underlying cause and effect relationships that occur at the within-field level. The... 相似文献
64.
Dolores Asensio Susan M. Owen Joan Llusi Josep Peuelas 《Soil biology & biochemistry》2008,40(12):2937-2947
We measured the terpene concentration in pentane and water extracts from soil horizons (litter, organic, top and low mineral) and from roots growing in top and low mineral horizons on a distance gradient from Pinus halepensis L. trees growing alone on a grassland. Terpene concentrations in pentane were higher than in water extracts, although β-caryophyllene showed relatively high solubility in water. The litter and roots were important sources of terpenes in soil. Alpha-pinene dominated in roots growing in both “top” (A1) and “low” (B) mineral horizons (123 ± 36 μg g−1 or 14 ± 5 mg m−2) and roots in low mineral horizon (270 ± 91 μg g−1 or 7 ± 2 mg m−2). Beta-caryophyllene dominated in litter (1469 ± 331 μg g−1 or 2004 ± 481 mg m−2). Terpene concentration in soil decreased with increasing distance to the trunk. This is likely to be related to changes in litter and roots type on the distance gradient from pine to grass and herbs. The relative contributions of all compounds, except α-pinene, were similar in the mineral soils and litter. This suggests that litter of P. halepensis is probably the main source of major terpene compounds. However, long-term emissions of α-pinene from P. halepensis roots might also contribute to α-pinene concentrations in rhizosphere soils. 相似文献
65.
Mechanical injury of sweet cherry fruit causes the disorder ‘surface pitting’, in which skin depressions overlie necrotic lesions in the fleshy mesocarp. Storage at temperatures near 0°C or the transfer of fruit from cool storage to room temperature worsened the disorder. Pretreating the fruit before cool storage with antitranspirant or surface-active agents exacerbated the disorder, but these effects were mitigated by the addition of CaCl2. Low O2, high CO2 and high humidity atmospheres did not affect the disorder, and low pressure storage was beneficial. 相似文献
66.
Science for action at the local landscape scale 总被引:4,自引:4,他引:0
Paul Opdam Joan Iverson Nassauer Zhifang Wang Christian Albert Gary Bentrup Jean-Christophe Castella Clive McAlpine Jianguo Liu Stephen Sheppard Simon Swaffield 《Landscape Ecology》2013,28(8):1439-1445
For landscape ecology to produce knowledge relevant to society, it must include considerations of human culture and behavior, extending beyond the natural sciences to synthesize with many other disciplines. Furthermore, it needs to be able to support landscape change processes which increasingly take the shape of deliberative and collaborative decision making by local stakeholder groups. Landscape ecology as described by Wu (Landscape Ecol 28:1–11, 2013) therefore needs three additional topics of investigation: (1) the local landscape as a boundary object that builds communication among disciplines and between science and local communities, (2) iterative and collaborative methods for generating transdisciplinary approaches to sustainable change, and (3) the effect of scientific knowledge and tools on local landscape policy and landscape change. Collectively, these topics could empower landscape ecology to be a science for action at the local scale. 相似文献
67.
W.J. Hartley M.R.C.V.S. Joan C. Kater B.V.Sc. E.D. Andrews M.Sc. A.N.Z.I.C. 《New Zealand veterinary journal》2013,61(5):118-120
Extract A great deal of evidence has now accumulated that immunity to helminth infection is acquired following natural exposure. Although this immunity is not absolute, animals that have been exposed to infection and survived are able to tolerate a much heavier intake of infective larvae than animals that have never been exposed. 相似文献
68.
M Gil N Kontoudakis E González M Esteruelas F Fort JM Canals F Zamora 《Journal of agricultural and food chemistry》2012,60(32):7988-8001
The aim of this paper was to study how maturity and maceration length affect color, phenolic compounds, polysaccharides, and sensorial quality of Cabernet Sauvignon and Tempranillo wines at three stages of grape ripening. Ripeness increased color extractability, phenolic compounds, and polysaccharide concentrations. Moreover, the proanthocyanidin mean degree of polymerization (mDP) and the percentage of prodelphinidins also increased with maturity, whereas the percentage of galloylation decreased. In general, wines from riper grapes contain higher proportions of skin proanthocyanidins. Color and anthocyanin concentration decreased when the maceration was longer, whereas polysaccharide and proanthocyanidin concentrations did the opposite. It was also detected that the mDP and the percentage of prodelphinidins decreased when the maceration was extended, whereas the percentage of galloylation increased. These data seem to indicate that proanthocyanidin extraction from seeds is clearly increased throughout the maceration time. 相似文献
69.
A Cáceres A Peña-Neira A Galvez E Obreque-Slier R López-Solís JM Canals 《Journal of agricultural and food chemistry》2012,60(35):8694-8702
The phenolic composition of wine depends on, among other factors, the grapes used to make it. In this sense, knowledge of the chemical composition of grapes and its association with the resulting wines is an important tool to determine if there is a relationship between the phenolic composition of grapes and the price that these wines obtain in the market. For this purpose, grape skins and seeds from the cultivar Cabernet Sauvignon from the central region of Chile, in 2009 and 2010 vintages from two ripening points, were subjected to chemical and phenolic analyses, as were the wines made from these grapes. Grapes and the corresponding wines from three retail price wine categories, U.S. $6-8, U.S. $28-30, and U.S. $150-160, were evaluated. No differences were found across the price categories in the chemical analysis of grapes. Berry skins and wines from the higher price categories presented a higher concentration only of total tannins, and the differences in their concentrations were only among the different fractions of proanthocyanidins in the skins, seeds, and wines; there were no differences in their proportions. A seasonal effect influenced the concentrations of certain compounds in grapes and led to a decrease in the concentration of total phenols, total tannins, and total anthocyanins between sampling dates as harvesting moved toward the common commercial grape harvest in Chilean viticulture. 相似文献
70.
Roberto Quiroz Joan O. Grimalt Pilar Fernandez Lluis Camarero Jordi Catalan Evzen Stuchlik Hansjoerg Thies Ulrike Nickus 《Water, air, and soil pollution》2011,215(1-4):655-666
Polycyclic aromatic hydrocarbons (PAHs) were analyzed in 70 soils distributed in mountain areas such as Montseny (300?C1,700 m), Pyrenees (1,500?C2,900 m), Alps (1,100?C2,500 m), and Tatras (1,400?C1,960 m). Average total PAH concentrations, excluding retene and perylene, were about 400 ng/g in the Pyrenees and 1,300?C1,600 ng/g in the other mountain ranges. No correlations between PAH concentrations and total organic carbon were observed. Retene was the major PAH in the Pyrenean soils of lower altitude. No altitudinal dependence was found between soil PAH concentrations and elevation for the whole dataset. However, in the Tatra soils a statistically significant correlation with altitude was observed involving higher concentrations at higher altitude. This correlation was due to the statistically significant altitudinal dependence of the more volatile PAHs. Another observed altitudinal trend concerned the benz[a]anthracene/(benz[a]anthracene + chrysene + triphenylene) and the benzo[a]pyrene/(benzo[a]pyrene + benzo[e]pyrene) ratios that exhibited a decrease in the more chemically labile compounds, benz[a]anthracene and benzo[a]pyrene, respectively, in the soils located at higher altitude. This observation is consistent with the expected higher photooxidation at higher mountain altitude. 相似文献