气候变化对长江干流流区径流量的影响

长江干流区在我国发展中有举足轻重的地位,是我国东西经济联系的纽带和桥梁。气候为化是当 象界讨论的重要课题,其对全球日益紧张的水资源影响已引起各国政府学者的关注。以重庆,万县,汉口,宜昌,贵池五站为代表,通过长江干流区近８０年观测资料和每站对应的气温,降水资料,分析了气候变化对长江干流区径流量的影响,以分组频率 找出了各站的枯水年,平均水年,丰水年。丰枯水年降水量距平百分率分别为２２．６％－３０．８     

近四十年来长江源区河流水沙量的变化

长江源区是指直门达水文站以上长江干支流的广大集水区域，是长江的重要水源涵养区。通过统计分析直门达站1957－1999年的43a间年径流量和年输沙量的变化情况，得出几个基本结论：长江源区年径流的变化主要受气候等自然因素的影响，年径流周期性变化较为明显，径流丰水年，偏丰水年出现最多的年份是20世纪60年代和80年代，枯水年和偏枯年出现最多的年份是70和90年代，总体上看40年间节径流基本稳定，但90年代比80年代有趋向偏枯的现象；年输沙量与年径流量的变化基本同步，年输沙量的变化主要取决于年径流量的变化，年输沙量也呈弱周期性变化状态，并有趋向减少的势头，近10a直门达站年径流量呈递减的趋势导致了年输沙量呈相应的变化；长江源区径流量和输沙量年内主要集中在5－10月，分别占年径流量和年输沙量的87．3％和99％；沱沱河由于径流以冰川补给为主，径流量与输沙量的变化呈现出不同的特征。     

近60年来气候变化和人类活动对长江中下游水文情势影响定量评价

为了定量评价长江中下游近60年来水文情势变化,运用Mann-Kendall非参数检验、均值差异T检验法对长江中下游宜昌、汉口和大通3个水文站1954～2016年径流量进行趋势和突变检验,采用累积量斜率变化率法,定量评估长江中下游气候变化和人类活动对径流量变化的影响,并运用RVA法对径流量突变前后32个水文指标改变度进行定量评价.研究结果表明:(1)长江中下游宜昌站和汉口站年径流量呈减少趋势,大通站年径流量总体呈增加趋势,总体变化趋势不显著,径流突变点分别发生在2002、2005和2006年,总体上与三峡水库蓄水时间相符;(2)三峡水库蓄水主要影响长江中下游径流年内变化,尤其是对年极值影响最大,且随着距离水库的增加,影响减弱;(3)宜昌、汉口和大通水文站水文改变度分别为55％、46％和32％,长江中下游河流水文情势总体上属于中高度改变;(4)气候变化占对中下游径流量改变贡献程度的70％左右,人类用水以及水库蓄水等人类活动贡献程度约占30％,气候变化是导致长江中下游年径流量发生改变的主导因素.     

2006年长江特枯径流特征及其原因初探

2006年长江流域出现了百年罕见的特大枯水,对长江流域用水和生态环境都产生了深远影响。使用2006年长江干支流主要水文站水情资料和长江流域气象资料,并同时考虑了三峡蓄水的影响,分析了2006年长江径流过程特征及其原因。研究发现,2006年长江径流量减少主要是汛期径流量显著减少所致,表现出“汛期特枯”的特点。径流量和水位最大降幅都出现在8~9月份,各站径流量最大减幅都超过50％,水位汛期也有显著下降。洞庭湖、汉江与历史同期相比,汛期来水也明显偏小;而鄱阳湖来水略丰,对干流枯水起到一定的缓和作用。7、8月份长江上游区（特别是屏山至宜昌区间）降水少气温高是形成长江汛期特枯的主要原因。气象变化与径流变化存在较好的对应关系。三峡蓄水使2006年10月宜昌站径流量减少了一半左右,而对10~11月大通径流减少影响率为187％。     

流域气候变化和人类活动对长江径流量影响的辨识(1956～2011)

利用1956~2011年的流域气温、降水量、径流量及有关文献所载蒸发量、水库修建、用水量、水土保持等资料,探讨气候变化和人类活动对长江径流量的影响。结果表明:(1)流域气温明显上升,且上升速率大于全球平均上升速率;(2)流域平均降水量下降了约1%,年降水量与年均气温之间无显著相关性;(3)年径流量随降水量频繁振荡,最大和最小值之比达1.9;(4)太阳净辐射量和风速下降导致流域自然蒸发作用减弱,而水库修建、耗水增多和水土保持等人类活动则使蒸发作用加强。两方面的影响相互削弱;入海年径流量下降1%;(5)流域内分区间存在差异,北域(岷江、嘉陵江和汉江)人类活动的影响居主导地位,径流量下降约15%;中域(金沙江以下干流两翼"未测区")则以气候变化的影响占优,径流量上升约9%;西域(金沙江流域)径流量减少4%;南域(乌江、洞庭湖和鄱阳湖流域)径流量上升2%。推断今后几十年气候要素仍将主导径流量的年际波动,而南水北调、新建水库、耗水增多和水土保持加强将可能使径流量再下降约10%。     

流域气候变化和人类活动对长江径流量影响的辨识

利用1956~2011年的流域气温、降水量、径流量及有关文献所载蒸发量、水库修建、用水量、水土保持等资料，探讨气候变化和人类活动对长江径流量的影响。结果表明：（1）流域气温明显上升，且上升速率大于全球平均上升速率;（2）流域平均降水量下降了约1%，年降水量与年均气温之间无显著相关性;（3）年径流量随降水量频繁振荡，最大和最小值之比达19;（4）太阳净辐射量和风速下降导致流域自然蒸发作用减弱，而水库修建、耗水增多和水土保持等人类活动则使蒸发作用加强。两方面的影响相互削弱；入海年径流量下降1%;（5）流域内分区间存在差异，北域（岷江、嘉陵江和汉江）人类活动的影响居主导地位，径流量下降约15%；中域（金沙江以下干流两翼“未测区”）则以气候变化的影响占优，径流量上升约9%；西域（金沙江流域）径流量减少4%；南域（乌江、洞庭湖和鄱阳湖流域）径流量上升2%。推断今后几十年气候要素仍将主导径流量的年际波动，而南水北调、新建水库、耗水增多和水土保持加强将可能使径流量再下降约10%     

长江-黄河源寒区径流量波动变化的气候因素分析

长江－黄河源区属典型寒区,降水、冰雪融水等共同成为径流的补给来源,径流量的变化同时受到区域内降水量和气温变化的影响。采用互谱分析方法研究表明,长江、黄河源区降水与径流周期波动间的关系明显好于气温与径流之间的关系,降水对径流量的主要周期波动有较明显的控制作用。气温虽然对径流量的部分周期波动变化有一定的影响,但不如降水明显。相对来说,黄河源区降水对径流量的波动变化的影响要好于长江源区。20世纪80年代后期长江－黄河源区径流量大幅下降的主要原因是区域内降水量的减少。     

长江上游重庆段径流变化归因分析

近年来,受气候变化和人类活动的双重影响,长江上游重庆段的年径流量持续减少。首先利用MASH移动窗口滑动平均法分析重庆市长江干流寸滩、北碚和武隆3个主要水文站的径流变化特征,然后运用弹性系数法和回归分析法进行径流模拟,定量评价气候变化和人类活动对径流变化的贡献率。结果表明:(1)与基准期(1961~1990年)相比较,影响评价期(1991~2011年)气候变化和人类活动对3个水文站年径流减少量的贡献率分别约为25.2%~35.2%和64.8%~74.8%。(2)气候变化对月径流量的影响幅度有限,导致7月汛期径流量有一定程度的增加,8~10月的径流量普遍减少;人类活动对月径流量影响明显,导致7月份实际径流量减少,并进一步加剧了8~10月径流量减少的幅度。(3)两种方法都指示人类活动已经成为径流减少的重要原因。定量阐明径流变化的成因有助于科学制定应对措施,协调重庆市以及长江上游水资源开发利用。     

21世纪长江黄河源区径流量变化情势分析

以长江、黄河源区为研究对象，应用大尺度半分布式水文模型(VIC)，结合江河源区气象站多年实测温度、降水数据，检验了VIC模型的适用性。模型能较好模拟江河源区地表径流，其Nash系数和相关系数分别达到了0.853 3和0.930 2（长江源区），0.889 2和0.924 8（黄河源区）。基于率定后的VIC模型，运用高分辨率的动力降尺度气象强迫资料，分析了未来气候变化情景下，江河源区径流量可能变化趋势。结果表明，未来30~50 a，长江、黄河源区年均径流量将分别增加858%、919%；未来80~100 a，长江、黄河源区年均径流量将分别增加1716%、721%。相对于2030~2049年而言，尽管年均降水增加006 mm/d，但是黄河源区2080~2099年径流量却将减少1.98%。运用植被情景假设及2030~2049年动力降尺度气象资料，模拟分析了植被变化对江河源区地表径流的影响。从4种地表覆被情景假设可以看出，林地地表覆被产生径流量最小，裸地最大。
     

三峡工程运行前后荆江三口水文情势的变化

基于1980～2015年荆江三口五站逐日流量数据,采用IHA指标体系分析度量三峡工程运行前后荆江三口水文情势的变化。除新江口和弥陀寺在枯水期1～3月有小幅增长外,三口各站点月均流量值均减小,汛期下降幅度较大。最大日流量值持续下降,但2003年后变化趋势相对平缓。沙道观和管家铺站断流天数显著上升,各站流量变化率明显降低。荆江三口水文情势变化受长江干流径流量减少、径流过程改变以及干流与口门河段河道冲淤不一致的共同影响,对长江中游四大家鱼种群以及洞庭湖苔草草洲的发展产生一定负面作用。     

WSSD 2002, Latin America and Brazil: Biodiversity and Indigenous People

Latin America comprehends notable variations in terms of natural environment, availability of natural resources, living standards, and demographic patterns. Latin America is a mosaic of cultures, post- and pre-Columbian. The rich variety of life forms discovered and described by chroniclers and traveling naturalists in the Neotropics contributed to the proposal, in mid-XVIIIth century, of a new system of classification and a scientific code of nomenclature for all organisms. Biodiversity was, for many centuries, a source of resources to be exploited in natura. In scientific circles, its inventory became the domain of taxonomists. But modern technology showed how important the miriad of life forms really are as sources of chemical molecules to be engineered as drugs and reassembled as novel manufactured products. We are on the brink of a new agricultural and medical revolution, thanks to the techniques of genetic engineering, which will lead eventually to the elimination of hunger and malnutrition.In this essay, the Brazilian environmental and social heterogeneity will serve as an example to illustrate some key points, which have influenced sustainability policies. The Amazon deforestation and indigenous knowledge (IK), subjects often associated with areas of high biodiversity, are usually the focus of environmental debates. The importance of IK in integrating development, reducing poverty and sustainability are considered together with the intellectual property rights of native populations.In the World Summit on Sustainable Development (WSSD) Implementation Plan, a few paragraphs were dedicated to Latin America, because of the pre-existing Action Platform on the Road to Johannesburg 2002, approved in Rio de Janeiro in October 2001. This paper calls attention to the need to draw up specific environmental policies for a region which shows an extremely high cultural and biological diversity, associated with a high availability of forests and water, among other resources.     

湘鄂赣农业资源与专业化区域化方向

湘鄂赣地理位置优越,农业资源丰富,稻谷、茶叶、麻类、棉花、油料、柑桔和淡水产品、禽蛋、肉类等在我国居有重要的地位,因此,大力发展三省农业生产,对我国人民实现小康生活具有战略意义。今后,要加速专业化区域化进程。我们找出生产潜力所在:改造低产田、低产园、低产水面;开发“三高”技术;开垦荒地、荒山、荒水;适当提高复种指数。通过建设,三省主要农产品将自给有余,还可满足国内外市场的需要。努力方向:高效农业开发——综合农业开发,吨粮田开发,玉米带开发,饲料稻开发,山区开发;合理布局农业生产;深化农业商品基地建设,发展综合利用,搞活商品流通;全面提高农业现代化水平,加强农业社会服务体系。     

Ethnosciences––A step towards the integration of scientific and indigenous forms of knowledge in the management of natural resources for the future

Integration of indigenous knowledge and ethnoscientific approaches into contemporary frameworks for conservation and sustainable management of natural resources will become increasingly important in policies on an international and national level, both in countries that are industrialised and those that have a developing status. We set the scene on how this can be done by exploring the key conditions and dimensions of a dialogue between ȁ8ontologiesȁ9 and the roles, which ethnosciences could play in this process. First, the roles of ethnosciences in the context of sustainable development were analysed, placing emphasis on the implications arising when western sciences aspire to relate to indigenous forms of␣knowledge. Secondly, the contributions of ethnosciences to such an ȁ8inter- ontological dialogueȁ9 were explored, based on an ethnoecological study of the encounter of sciences and indigenous knowledge in the Andes of Bolivia, and reviewed experiences from mangrove systems in Kenya, India and Sri Lanka, and from case-studies in other ecosystems world-wide, incl. Australia, Burkina Faso, Ecuador, Ethiopia, Guatemala, Indonesia, Nepal, Niger, Philippines, Senegal, South-Africa and Tanzania.     

Paradoxical ozone associations could be due to methyl nitrite from combustion of methyl ethers or esters in engine fuels

We review studies of the effects of low ambient ozone concentrations on morbidity that found a negative coefficient for ozone concentration. We call this a Paradoxical Ozone Association (POA). All studies were in regions with methyl ether in gasoline. All but one study carefully controlled for the effects of other criterion pollutants, so the phenomenon cannot be attributed to them. One was in southern California in mid-summer when ozone levels are highest. Because ozone is created by sunlight, the most plausible explanation for a POA would be an ambient pollutant that is rapidly destroyed by sunlight, such as methyl nitrite (MN). A previously published model of engine exhaust chemistry suggested methyl ether in the fuel will create MN in the exhaust. MN is known to be highly toxic, and closely related alkyl nitrites are known to induce respiratory sensitivity in humans. Support for the interpretation comes from many studies, including three linking asthma symptoms to methyl tertiary butyl ether (MTBE) and the observation that a POA has not been seen in regions without ether in gasoline. We also note that studies in southern California show a historical trend from more significant to less significant ozone-health associations. The timing of those changes is consistent with the known timing of the introduction of gasoline oxygenated with MTBE in that region.     

Prognosis of the spatiotemporal dynamics of ecosystems by means of universal kriging

The use of quantitative data for constructing prognostic maps of the dynamics of ecosystem degradation and restoration by nonlinear simulation methods is a topical field of landscape ecology. This method of dynamic cartography is based on fiberwise comparison of data on the state of Chernye Zemli (the Kalmyk Republic, Russia) in different years and the detailed analysis of the period on which the prognosis was based. For this purpose, materials of repeated aerial and satellite photography obtained during a long period (1954–1993) were used. Comparison of maps characterizing the dynamics of Chernye Zemli between 1958 and 1993 allows prognostic electronic maps for the next 10–15 years (with a five-year interval) to be drawn and land prognosis for the next 20–30 years (1998–2023) to be obtained. Deceased     

Distributions of personal VOC exposures: a population-based analysis

Information regarding the distribution of volatile organic compound (VOC) concentrations and exposures is scarce, and there have been few, if any, studies using population-based samples from which representative estimates can be derived. This study characterizes distributions of personal exposures to ten different VOCs in the U.S. measured in the 1999-2000 National Health and Nutrition Examination Survey (NHANES). Personal VOC exposures were collected for 669 individuals over 2-3 days, and measurements were weighted to derive national-level statistics. Four common exposure sources were identified using factor analyses: gasoline vapor and vehicle exhaust, methyl tert-butyl ether (MBTE) as a gasoline additive, tap water disinfection products, and household cleaning products. Benzene, toluene, ethyl benzene, xylenes chloroform, and tetrachloroethene were fit to log-normal distributions with reasonably good agreement to observations. 1,4-Dichlorobenzene and trichloroethene were fit to Pareto distributions, and MTBE to Weibull distribution, but agreement was poor. However, distributions that attempt to match all of the VOC exposure data can lead to incorrect conclusions regarding the level and frequency of the higher exposures. Maximum Gumbel distributions gave generally good fits to extrema, however, they could not fully represent the highest exposures of the NHANES measurements. The analysis suggests that complete models for the distribution of VOC exposures require an approach that combines standard and extreme value distributions, and that carefully identifies outliers. This is the first study to provide national-level and representative statistics regarding the VOC exposures, and its results have important implications for risk assessment and probabilistic analyses.     

Household water in rural asia: a case study of the construction of a piped water system in Bangui,Ilocos Norte,Philippines

In early 1980 an extension agent was assigned to the rural municipality of Bangui, Ilocos Norte, Philippines to work on development projects – in particular the improvement of the supply of safe water for drinking and sanitation. After many months of visiting spring sites and meeting with community leaders, a small part of the municipality was selected to build a gravity fed piped water system. Although the system took many months to plan, identify funding and construct, the 600 community members were ultimately rewarded with house to house connections that enabled them to achieve per capita water consumption levels above the minimum levels recommended by the World Health Organization. Of course, money was critical to ensure the project’s success, but many other factors played an equally critical role. For instance, without the active participation of the community and the unwavering support of the community leadership the project would not have survived the initial planning stage. Also, the extension agent played a critical role by acting as a conduit between funding agencies, the Bureau of Public Works and the community. The primary lesson to be learned from this experience is that the success of rural development projects is largely driven by the synergy between the community, technical support, financial support, and agents of change such as extension agents. If any of these ingredients had been lacking, the project result would likely have been far different.     

Geographic Variation in the Seasonal Reproductive Strategy of the Mite Varroa jacobsoni in the Honeybee Nest

Variation in the reproduction of Varroa jacobsoni mite was studied in relation to the expansion of the range of its parasitism on the honeybee. Geographic differences in the seasonal dynamics of mite reproduction in the nests of bee families were revealed. Variation in the sex ratio of mites and the factors inhibiting their reproduction at the northern boundary of the honeybee range are considered. The forms of parthenogenetic reproduction in V. jacobsoni are discussed.     

Long-term increase in climatic dryness in the East-Mediterranean as evidenced for the island of Samos

The Eastern Mediterranean region is among the regions which were predicted to become drier under IPCC climate scenarios. Here, we document a gradual reduction of rainfall and tree growth and the loss of rural springs during the last decades of the twentieth century. Years with severe drought are associated with very low tree growth (dendrochronology) and dry falling of springs as evidenced by interviews with local stakeholders. The paper discusses the consequences of accelerating drought on natural vegetation and agriculture and points at the interaction with fire dynamics and economy, both likely to enhance the drought effect.