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991.
Santiago Beguería Juan I.López-Moreno Adrián Lorente Manuel Seeger José M.García-Ruiz 《Ambio-人类环境杂志》2003,32(4):283-286
在地中海国家扩大灌溉土地的面积,应当考虑气候与土地利用变化对水资源的影响.本文利用降水和温度资料,分析了20世纪中叶以来西班牙比利牛斯山脉中部流域径流的变化趋势.降水与径流之间关系的年变化表明,径流在所研究期间的后半时段相对较低,这一趋势与土地利用变化一致.在月水平上,降水量在10月、4月和7月明显增加,而在3月则有下降;温度在1月和2月有所增加,而在4月则趋于下降.但过去50年间径流在大部分月份中呈显著下降趋势,土地利用和植被覆盖的变化是解释年平均径流下降大约30%的惟一非气候因素. 相似文献
992.
Food and Environmental Virology - Survival of tick-borne encephalitis virus was studied from pasteurized and unpasteurized goat milk and from salted/unsalted and spiced/unspiced cheese made from... 相似文献
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995.
We introduce a flexible and scalable class of Bayesian geostatistical models for discrete data, based on nearest-neighbor mixture processes (NNMP), referred to as discrete NNMP. To define the joint probability mass function (pmf) over a set of spatial locations, we build from local mixtures of conditional pmfs using a directed graphical model, with a directed acyclic graph that summarizes the nearest neighbor structure. The approach supports direct, flexible modeling for multivariate dependence through specification of general bivariate discrete distributions that define the conditional pmfs. In particular, we develop a modeling and inferential framework for copula-based NNMPs that can attain flexible dependence structures, motivating the use of bivariate copula families for spatial processes. Moreover, the framework allows for construction of models given a pre-specified family of marginal distributions that can vary in space, facilitating covariate inclusion. Compared to the traditional class of spatial generalized linear mixed models, where spatial dependence is introduced through a transformation of response means, our process-based modeling approach provides both computational and inferential advantages. We illustrate the methodology with synthetic data examples and an analysis of North American Breeding Bird Survey data. 相似文献
996.
Góes Mariana Moraes Merci Aline Andrello Avacir Casanova Yamashita Fabio de Carvalho Gizilene Maria 《Journal of Polymers and the Environment》2021,29(6):2000-2012
Journal of Polymers and the Environment - The search for highly productive agriculture has considerably increased the use of fertilizers, becoming a worrying source of environmental and health... 相似文献
997.
Manure application supplies plant nutrients, but also leads to trace element accumulation in soil. This study investigated total and EDTA-extractable B, Cd, Co, Cu and Zn in soil after 25 annual manure applications. The residual effect of 14 annual manure applications followed by 11 yr with no applications was also investigated. Manure was applied at 0, 30, 60 and 90 Mg ha(-1) yr(-1) (wet weight) under rainfed (treatments Mr0, Mr30, Mr60, and Mr90) and at 0, 60, 120 and 180 Mg ha(-1) yr(-1) under irrigated conditions (Mi0, Mi60, Mi120, and Mi180). The manure applications had no significant effect on soil B, Cd and Co content under both rainfed and irrigated conditions, but significantly increased total Cu and Zn content under irrigated conditions with Zn in Mi120 and Mi180 reaching the lower maximum concentration (MAC) level set by the European Community. Manure application also significantly increased EDTA-extractable Cd and Zn content in soil. Up to 27% of the total Cd (0.156 mg kg(-1)) and 21% of total Zn (38 mg kg(-1)) are found in EDTA-extractable form (Mi180 at 0-15 cm). EDTA-extractable Cd and Zn content was also significantly elevated in the irrigated residual plots due to the higher manure rates used. Thus, the impacts of cattle manure application on trace elements in soil are long lasting. Elevated Cd and Zn are a concern as other studies have linked them with certain types of cancers and human illnesses. 相似文献
998.
Mónica Martínez-Martínez Marta Diez-Valcarce Marta Hernández David Rodríguez-Lázaro 《Food and environmental virology》2011,3(2):92-98
Synthetic multiple-target RNA and DNA oligonucleotides were constructed for use as quantification standards for nucleic acid
amplification assays for human norovirus genogroup I and II, hepatitis E virus, murine norovirus, human adenovirus, porcine
adenovirus and bovine polyomavirus. This approach overcomes the problems related to the difficulty of obtaining practical
quantities of viral RNA and DNA from these viruses. The quantification capacity of assays using the standards was excellent
in each case (R
2 > 0.998 and PCR efficiency > 0.89). The copy numbers of the standards were equivalent to the genome equivalents of representative
viruses (murine norovirus and human adenovirus), ensuring an accurate determination of virus presence. The availability of
these standards should facilitate the implementation of nucleic acid amplification-based methods for quantitative virus detection. 相似文献
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1000.
Modern carbonate globules, located in cracks of submerged volcanic rocks and in calcareous pinnacles in alkaline (sodic) Lake Van, Turkey, appear to be analogues for the ~3.9 billion-year-old carbonate globules in Martian meteorite ALH84001. These terrestrial globules have similar diameters and are chemically and mineralogically zoned. Furthermore, they display surface and etching structures similar to those described from ALH84001, which were interpreted as fossilized microbial forms. These terrestrial carbonates formed at low temperatures where Ca-rich groundwaters enter the lake. Chemical, mineralogical, microbiological, and biomolecular methods were used in an attempt to decipher the process responsible for the genesis of these structures. Although the exact mode of formation of Lake Van carbonates remains an enigma, their similarity to the Martian globules indicates that the ALH84001 carbonates may have formed in similar setting on ancient Mars. 相似文献