【摘 要】
：
In order to understand the physiological activities of Pinus sylvestris var.mongolica (MP) and to provide a proper management for regional water resources,the water uptake and utilization strategy of
【机 构】
：
Institute of Applied Ecology, Chinese Academy of Sciences
【出 处】
：
中国科学院“百人学者论坛”2011学术研讨会
论文部分内容阅读
In order to understand the physiological activities of Pinus sylvestris var.mongolica (MP) and to provide a proper management for regional water resources,the water uptake and utilization strategy of MP plantations (sites:Zhanggutai (pure) and Daqinggou (savanna) and nature forests (site:Honghuaerji) were studied.The stable isotope (?D and ?18O) was used to determine the water use source of MP plantations;the stable isotope (?13C) was used to study the intrinsic water use efficiency (iWUE) of both MP plantations and nature forests;the sap flow of MP trees was monitored by thermal diffusion probes,and the water consumption of stands were estimated.
其他文献
随着人类活动引起的大气活性氮、硫等化合物的大量排放,来自大气的氮、硫等环境养分数量也越来越引起人们的重视。本文以大气氮素沉降为例对环境养分的概念、研究方法、数量及其与人为活性氮排放的关系进行了阐述。综合研究发现,大气氮素干湿沉降等环境养分已经成为我国陆地生态系统一项重要的养分资源,其数量高达1800 万吨/年,干湿沉降的数量基本相当。其中,输入农田的环境氮养分可达大气氮沉降总量的1/3,相当于全国
海河流域是我国水系统受人为影响最剧烈的地区之一,特别是七十年代以来,由于人口增长和经济、社会、农业发展驱动,水资源问题愈演愈烈,形成有河皆枯,以及世界上面积最大的地下水漏斗.研究通过量化农业用水,研究农业用水对地表水、地下水系统的影响,表明:人类活动是地表水系统演变的主要因素,农业用水特别是农村实行联产承包责任制初期,是该流域水系统转变的主要时期,地表水流量萎缩的程度与各子流域农业用地的规模直接相
NO是氮生物地球化学循坏的重要产物,在生态系统中主要通过土壤硝化-反硝化过程产生并排放.然而,在人苏达盐渍土NO的排放与吸收过程却研究极少.利用实验室控制实验研究松嫩平原西部4 种不同土地利用方式下苏达盐渍土NO生物排放,结果表明:自然草原、人工草原、盐渍土水稻田、伴沙盐渍土水稻田NO产生与排放的最佳含水量分别为14.0％,9.0%,9.5%,and18% WFPS,在同一土壤湿地前提下,NO通量
Using the data from the Proportional Counter Array and the High-Energy X-ray Timing Experiment on board the Rossi X-Ray Timing Explorer satellite,we investigate the evolution of the 3-220~keV spectra
Soil organic matter accumulation in farmland is not only vital for the maintenance of soil productivity,but also for the mitigation of global warming.Rice-wheat rotation agroecosystem is one of the pr
Although several genes have been shown to be essential for the dorsal pancreas specification,little is known about the ventral pancreas specification.Liver and ventral pancreas are derived from a comm
Telomeres are the nucleoprotein structures situated at linear chromosomalends.Their integrity is required for cell proliferation and survival.The vast majority of eukaryotic species use telomerase as
微生物之所以能形成生物膜是因为有胞外多聚物( extracellular polymeric substances,EPS)组成的基质网(matrix)将单个的细菌联合在一起.该基质网是如何形成,以及在生物膜发育过程中是否有相应的变化并不很清楚.在此报道中,我们以铜绿假单胞菌作为模式菌对该问题进行了探索性研究.利用与生物膜基质网关键多糖Psl 特异性结合的凝集素标记,我们观测了整个生物膜发育过程中
Winter photosynthesis of trees was well studied for boreal,Mediterranean,and some temperate forests,while little is known about the forests from tropical-subtropical transition zones and subtropical a
据美国Frost &Sullivan 公司的调查报告显示,至2010 年全球各类造影剂销售额已超过200 亿美元,而且每年以6-8 ％的速度在全球范围内增长.根据有关数据显示,在中国国内医药市场上,各种造影剂每年以25-30 ％的速率递增.由于人口基数庞大,中国形成了巨大的潜在市场,国外的大型医药、医疗器械公司纷纷看好中国的造影剂市场.目前,绝大部分的造影剂依赖进口,价格昂贵,中国很少有自主知识产