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101.
通过问卷调查和SPSS软件,分析和探讨了农民气候适应性行为的现状及影响因素,并在此基础上思考探讨应对之策,即建立和健全农业科技服务体系,加强对农民气候认知和适应能力的教育培训,推进农民之间气候适应性行为的合作,加强对农民气候适应性行为的指导。 相似文献
102.
通过对塔里木盆地北部全新世地层中27块样品的孢粉分析,根据其组合特征并结合表土花粉分析,本区全新世以来除了塔里木河中游隐域性植被成分随着河流改道变化频繁外,两侧显域性的早生、超旱生荒漠植被成分无明显变化,它们的生境反映了气候环境总的形势是持续干旱的。但全新世地层中孢粉种属和丰度的变化,蒿属、藜科和麻黄花粉相对数量的增减也说明了在干旱背景中本区气候有微弱的干湿波动,表现为全新世早期和晚期气候偏凉湿,中期气候干暖,但干暖期鼎盛阶段略湿。 相似文献
103.
潘安定 《干旱区资源与环境》1993,(2)
本文基于将今论古的历史比较法,根据多方面资料分析,论证了新疆在独特的地理环境下,冷湿和暖干的对应是晚更新世以来气候变迁的一般规律。文中探讨了大气环流的影响,认为季风气候是形成我国东部地区暖湿和冷干相结合的主要因素。典型的大陆性气候使新疆的温湿组合状况与东部地区相反。东西两种状况的交界带应是季风气候影响范围的界限。 相似文献
104.
聚类分析在家畜引种中的应用 总被引:3,自引:0,他引:3
本文以小尾寒羊为例,应用聚类分析的方法对三十一个生态区域的八个气候因子进行了分类研究,介绍了聚类分析在家畜引种中的应用。结果表明,这三十一个生态区域可以分为六类,凡与小尾寒羊原产地分为同一类的生态区域可以引种小尾寒羊,其他类的生态区域不宜引种小尾寒羊。 相似文献
105.
应用GCMs和历史气候资料生成我国在CO2倍增时的气候情景 总被引:21,自引:2,他引:19
采用3种大气环流模型(GCMs)的输出结果,并结合我国各地有代表性气象台站20-30年的逐日气象资料,在微机上生成了我国在CO_2倍增时的3种气候情景.进而分析了我国未来温度、降水和太阳辐射3要素可能的时空分布特征和季节变化趋势,并推测我国易受全球气候变化不利影响的脆弱地区. 相似文献
106.
Introduction 总被引:1,自引:0,他引:1
The realization of strategies for sustainable land use assumes specificresearch concepts from the local to the global scale (micro-, meso- andmacroscale). Therefore, landscape ecological science has to provideinvestigation methods for all these different scales. By combiningtop-down and bottom-up approaches in addition tocoupled GIS-model applications and traditional methods, the investigation oflandscape ecological structures and processes seems to be possible. Thepresented studies show this approach on examples of two study areas in EasternGermany: A watershed of 400 km2 and an administrativedistrict of about 4000 km2. The scale-specificapplicability of several models and methods were tested for theseinvestigations, and the validation of the calculated results are presented. Animportant outcome of the project should be the prevention of conflicts betweenagriculture, water management and soil, and water and nature conservation;based onrecommendations for land use variants with decreased pollutant loading withinagricultural areas. The scale specific investigations can be considered as abase for establishing sustainable land use.This revised version was published online in May 2005 with corrections to the Cover Date. 相似文献
107.
环境因素对丹顶鹤越冬行为的影响 总被引:3,自引:0,他引:3
丹顶鹤在盐城越冬期间各种环境因素对其行为都将产生一定的影响,对此我们进行了观察记录。该项工作主要用8×40、10×50双筒和20倍单筒望远镜实地观察、照相机摄影等直接记录丹顶鹤的各种行为;种群数量计算为直接计数法;气候因子则根据各级气象部门的预报结果,结合观察点温度计等手段测算。结果表明丹顶鹤越冬期间,气候因子的变化是对其行为产生直接影响的主要因素,温度、雨、雾、雪、风等发生大幅度变化时,都将导致越冬期丹顶鹤的行为发生相应的适应性变化,对迁徙行为的影响则更为明显。而食物和水源则通过气候因子的变化和安全度的影响再次反应到丹顶鹤的越冬行为中来。本文最后提出了减轻灾害性天气对丹顶鹤越冬行为的影响建议。 相似文献
108.
Are hedgerows effective corridors between fragments of woodland habitat? An evidence-based approach 总被引:1,自引:1,他引:1
Anthropogenic modification of the countryside has resulted in much of the landscape consisting of fragments of once continuous
habitat. Increasing habitat connectivity at the landscape-scale has a vital role to play in the conservation of species restricted
to such remnant patches, especially as species may attempt to track zones of habitat that satisfy their niche requirements
as the climate changes. Conservation policies and management strategies frequently advocate corridor creation as one approach
to restore connectivity and to facilitate species movements through the landscape. Here we examine the utility of hedgerows
as corridors between woodland habitat patches using rigorous systematic review methodology. Systematic searching yielded 26
studies which satisfied the review inclusion criteria. The empirical evidence currently available is insufficient to evaluate
the effectiveness of hedgerow corridors as a conservation tool to promote the population viability of woodland fauna. However,
the studies did provide anecdotal evidence of positive local population effects and indicated that some species use hedgerows
as movement conduits. More replicated and controlled field investigations or long-term monitoring are required in order to
allow practitioners and policy makers to make better informed decisions about hedgerow corridor creation and preservation.
The benefits of such corridors in regard to increasing habitat connectivity remain equivocal, and the role of corridors in
mitigating the effects of climate change at the landscape-scale is even less well understood. 相似文献
109.
全球气候变化对松嫩草原土壤水分和生产力影响的研究 总被引:6,自引:1,他引:5
本文首先模拟计算松嫩草原土壤水量平衡,并结合未来气候情景估算松嫩草原土壤水分的变化。最后,在土壤水分研究的基础上,初步评估全球气候变化对松嫩草原生产力的影响。 相似文献
110.
Recent studies have emphasized the presence of microclimates in urban settings, but most do not have the high resolution observations necessary to understand the interactions taking place at a neighborhood scale. This study used a network of 10 identical weather stations and high resolution land cover data in Knoxville, Tennessee, to analyze the microclimates of a medium-sized city with a temperate climate. Two stations were installed in each of four urban neighborhoods in locations with varying localized tree cover, and two additional stations were installed in the center of downtown and in a nearby urban nature center. The intra-neighborhood results suggested that there is significant temperature variability within a single neighborhood based on the tree canopy density immediately surrounding a given weather station. However, the inter-neighborhood variability (differences between neighborhoods) was similar in magnitude, which suggests that the overall differences in neighborhood characteristics also have an effect on climate. Land cover at the neighborhood scale (in particular tree canopy percentages at the 500-m radii) had the highest correlation with the minimum daily temperature (Tmin) during the summer season. Maximum daily temperature (Tmax) relied most on the distance of each station from Downtown and the amount of impervious area in the 50 m surrounding each station. Tmax was also most influenced by surrounding land cover during dry conditions (a Dry Moderate air mass). Overall, highly localized impervious land cover percentages and larger-scale forested canopy were important in explaining temperature fluctuation, pointing to the importance of scale in microclimate assessments. Dry air masses enhanced the relationship between land cover and temperature during the day, while moist air masses did the same overnight. These data can be used to better inform planning strategies to build resiliency to extreme heat into urban environments by considering the influence of tree canopy. 相似文献