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1.
京津冀鲁豫地区小麦优化灌溉的农业气候依据   总被引:2,自引:0,他引:2  
安顺清  焦仪珍 《气象学报》1992,50(3):320-326
根据巩县和泰安4年小麦水分试验资料,分析确定了冬小麦最佳耗水量。从充分利用自然降水和土壤贮水角度出发,分析了影响麦田水分状况的各种因子,得出全生育期水分供需差。进而根据小麦阶段耗水的差异和麦田水分动态分析,确定了小麦适宜灌溉期。在上述基础上得出该区小麦优化灌溉方案,通过大面积推广应用,证明该方案可行,具有重大经济效益。  相似文献   

2.
受气候增暖和人类活动的双重影响,黄河流域的水循环正在发生显著变化,水资源供需矛盾突出。陆地水循环是一个复杂的非线性系统,为清晰认识水循环变化的全貌,并合理高效利用有限的水资源量,需要综合考虑水循环各个要素之间的协同变化机制。同时,在“人类世”背景下,黄河流域水循环研究必须考虑人类活动的影响,主要包括植被变化和人类用水,其中人类用水主体为农业灌溉。自从实施生态恢复工程以来,黄土高原植被覆盖明显改善的同时也引发了对径流、蒸散发、降水、土壤湿度以及地下水的一系列影响,且研究结论还存在一些争议,但黄土高原植被覆盖改善使得该地区蒸散发量增加基本达成共识,大多数研究支持植被改善减少径流的结论。黄河流域的农业灌溉方式主要为大水漫灌,其对地表蒸散发、地表水及地下水多个过程具有重要影响。本文主要针对黄河流域的水循环研究,讨论相关研究进展以及发展方向。  相似文献   

3.
Advance knowledge of conflicting trajectories of water–energy–food (WEF) nexus is highly relevant for water policy and planning, especially for basins that cross national boundaries. The Brahmaputra River Basin in South Asia, home for 130 million people, is such a basin. Development of new hydropower projects, upstream water diversions and possible climate changes introduce concerns among riparian countries about future water supply for energy and food production in the basin. This study presents a new hydro-economic water system model of the basin coupled with ex post scenario analysis under the “nexus thinking” concept to identify and illustrate where development paths are in conflict. Results indicate that the ability of future development to remain free of conflict hinges mostly on the amount of precipitation falling in the basin in the future. Uncertain future precipitation along with uncertain future temperature and the unknown amount of upstream water diversion combine to strongly influence future water, energy and food production in the basin. Specifically, decreases in precipitation coupled with large upstream diversions (e.g., diversion in the territory of China) would leave one or more riparian countries unable to secure enough water to produce their desired energy and food. Future climate projected by General Circulation Models suggest a warmer and wetter climate condition in the region, which is associated with an increase in streamflow and easing of conflicts at the WEF nexus in the basin. The methodology presented here is expected to be generally useful for diagnosing the conditions that may cause water resources development goals to not be achieved due to either changes in climate or water use among competing users.  相似文献   

4.
The balance of water, heat, and solutes in the Dnieper-Bug estuary is estimated using the data of long-term observations (from 1965 to 2011) for solving the practical problems associated with the rational use of water resources in this area.  相似文献   

5.
The spatial distribution of methane content and methane fluxes in the water in the north-western part of the Sea of Japan, in the Kuril basin of the Sea of Okhotsk, and in the near-Kuril part of the Pacific Ocean is studied using the data of marine research expeditions in 2005, 2010, and 2011. The studies revealed the significant variability of the methane flux depending on the source presence and on the sea surface conditions. The high emission of methane from water to the atmosphere is registered in the areas where its concentration exceeds the equilibrium values with the atmosphere. The use of the model of computation of the fields of currents and contaminant transport for the investigated water area enabled explaining the formation of the high concentration of methane in the center of vortices in the zones of sea water convergence in the water areas under study.  相似文献   

6.
水分胁迫对华北平原冬小麦地上部分及产量的影响   总被引:1,自引:0,他引:1  
以“济麦-22”为供试品种,利用中国气象局固城生态环境与农业气象试验站大型根系观测系统,研究冬小麦在重度干旱胁迫(≤40.0%)、轻中度干旱胁迫(40.1%-55.0%)和适宜(55.1%-80.0%)3种水分胁迫条件下地上部分对水分胁迫的响应,以探索水分胁迫对华北平原冬小麦产量的影响,分析不同水分胁迫对冬小麦产量的影响程度。结果表明:华北平原冬小麦在轻中度干旱胁迫和重度干旱胁迫下,小麦全生育期的天数缩短,株高、叶面积及灌浆速率均呈不同程度的减少。3种水分胁迫的株高增长量为适宜>轻中度胁迫>重度胁迫,灌浆速率为适宜>轻中度胁迫>重度胁迫。土壤水分胁迫引起冬小麦物质分配更多地向支持生长的茎秆转移,在生长发育过程中受到水分胁迫,小麦产量将降低,重度胁迫条件下小麦产量为适宜水分条件的69%。  相似文献   

7.
A numerical stream temperature model that accounts for kinematic wave flow routing, and heat exchange fluxes between stream water and the atmosphere, and stream water and the stream bed is developed and calibrated to a data-set from the Lower Madison River, Montana, USA. Future climate scenarios were applied to the model through changes to the atmospheric input data based on air temperature and solar radiation output from four General Circulation Models (GCM) for the region under atmospheric CO2 concentration doubling. The purpose of this study was to quantify potential climate change impacts on water temperature for the Lower Madison River, and to assess possible impacts to aquatic ecosystems. Because water temperature is a critical component of fish habitat, this information could be of use in future planning operations of current reservoirs. We applied air temperature changes to diurnal temperatures, daytime temperatures only, and nighttime temperatures only, to assess the impacts of variable potential warming trends. The results suggest that, given the potential climatic changes, the aquatic ecosystem downstream of Ennis Lake will experience higher water temperatures, possibly leading to increased stress on fish populations.Daytime warming produced the largest increases in downstream water temperature.  相似文献   

8.
黄冈市水资源分析与利用   总被引:3,自引:1,他引:3  
南阳春  李国华 《气象》2004,30(7):47-51
通过计算黄冈市各县市及不同水系降水、径流、蒸发等要素的时空分布、不同保证率工农业生产、人民生活对水资源的需求,分析了黄冈市水资源的分布规律,总结了平水、偏旱、干旱三种典型年全市水资源的盈亏特征。指出,黄冈市水资源总量丰富,开发利用潜力很大,但因时空分布不均,导致水旱灾害频繁,需要采取综合措施,努力提高人均占有量和资源利用率。  相似文献   

9.
The present study is an attempt to analyse the precipitable water vapour (PWV) derived from Global Positioning System (GPS) and observed meteorological data over Almora, Central Himalayan Region. The PWV values derived using GPS study is compared with the corresponding moderate resolution imaging spectro-radiometer (MODIS) data. The statistical analysis reveals a positive correlation between both methods. Moderate resolution imaging spectroradiometer near-infrared (MODIS NIR) clear column water vapour product shows a higher correlation (R 2 = 90–93 %) with GPS-derived precipitable water vapour on annual scale as compared to the seasonal scale (R 2 = 62–87 %). MODIS is found to be overestimating in NIR clear column where the magnitude of bias and RMSE show systematic changes from season to season. Monsoon is an important phenomenon in the Indian weather context and holds significant importance in Central Himalayan ecosystem. The monthly and seasonal variation in precipitable water vapour is related with monsoon onset in the region. Diurnal variations in precipitable water vapour are studied with other meteorological data over Almora during dry and wet season. The precipitable water vapour had minimum value in the morning, increases in the afternoon to evening and again decreases to the midnight in both the dry and wet seasons. These results suggest that diurnal variation of water vapour is caused by the transport of water vapour by thermally induced local circulation.  相似文献   

10.
Throughout history settlements have been abandoned due to lack of water. Such a fate is of concern to public officials in settlements facing water scarcity - a condition which is anticipated to increase due to the impacts of climate change, and other factors including increasing per capita water use, and population growth. Key questions surround how to best adapt to these circumstances. A strategy little explored is relocation. This paper presents results from a qualitative study conducted in eight geographically diverse Australian locations. The willingness of individuals to relocate under three hypothetical water scenarios was investigated: (1) if the water in their community ran out, (2) if recycled wastewater was put in their community's drinking water supply, and (3) if desalinated water was put in their community's drinking water supply. Results indicate that most people would not relocate if recycled or desalinated water was used to augment their community's drinking water supply, but they would if their water supply ran out. Our results highlight that while there is initial public opposition to the augmentation of existing potable water supplies with recycled or desalinated water, people would prefer these solutions, over being forced to move location. Respondents were highly aware of the social, economic and public infrastructure costs associated with relocation decisions. Relocation would therefore, for most, only be the very last option if their water demands could not be met. However, it was difficult for most to imagine the situation becoming so dire. Our results highlight the importance of a comprehensive and consultative approach to managing supply in water scarce locations.  相似文献   

11.
探空、地面及卫星资料反演水汽含量的比较   总被引:1,自引:0,他引:1  
利用探空、地面等常规探测资料及卫星遥感资料计算了我国中西部地区2007年6月—2008年5月间水汽含量的空间分布和时间演变,结果显示:由探空资料计算的整层大气水汽含量的空间变化,总体形势是,纬度低的地区水汽含量多,纬度高的地区水汽含量少;各探空站上空水汽分布的季节演变规律比较一致,夏季水汽含量最大,冬季最小,春秋季节基本相当。根据探空资料建立地面水汽压与大气总水汽量的经验关系,利用地面站资料确定水汽分布,与同时次探空站资料估算的水汽场相比,两者分布趋势基本一致。利用FY-2C卫星的可见光和红外分裂窗通道资料,建立反演大气水汽含量的回归关系式,与探空资料计算的结果相比,总体上变化趋势较一致。  相似文献   

12.
刘煜  刘蓉  王欣  王作亮 《高原气象》2022,41(1):58-67
干旱指数一直以来是评估一个地区地表干湿状态的有效标准.为了认识青藏高原若尔盖地区在极端干旱和湿润条件下的水汽空间分布格局,本文基于地面观测资料计算月尺度的标准化降水蒸散指数,提取2000-2017年青藏高原若尔盖地区的极端干旱和湿润状况,利用拉格朗日后向轨迹模型模拟该地区极端干湿条件下的水汽输送路径,并评估潜在水汽源地...  相似文献   

13.
余洋  万蓉  张文刚  周文 《暴雨灾害》2020,30(4):354-362

利用神农架机场站2016年6月23日11时—24日08时(北京时,下同)和咸宁站2016年7月3日04时—4日01时两次暴雨过程的地面小时降水数据及同址微波辐射计观测数据反演的地面至10 km高度共58层的水汽密度、液态水含量、相对湿度和温度廓线,以及站点水汽总量、液态水总量、云底高度等资料,得到两次暴雨过程中,位于山地的神农架与位于平原的咸宁的暴雨前后大气垂直结构差异。神农架水汽总量、液态水总量均低于咸宁,测站上空各高度的水汽密度、液态水含量、温度也低于咸宁对应高度的数值,混合层的相对湿度略大于咸宁。多要素综合分析认为:(1)神农架处于山地,外来水汽供应不够充分,降水的形成主要依靠本地水汽凝结产生;由于山地海拔较高,神农架大气层结温度相对较低,冰晶效应的温湿条件较咸宁好,冰晶效应使得神农架在水汽供应不够充足的情况下产生暴雨。(2)咸宁水汽供应充足,水汽凝结之后可以得到及时补充;咸宁尽管混合层的湿度条件不如神农架,冰晶的凝结增长相对较弱,但混合层的凇附过程和融化层的云雨滴碰并都在降水过程中起到重要作用。(3)降水开始前神农架的大气抬升作用比咸宁的强,地形对气流的阻挡抬升作用明显,而降水开始后咸宁的大气抬升作用更显著,表现出明显的对流性特征。

  相似文献   

14.
Latitudinal heat transport in the ocean and atmosphere represents a fundamental process of the Earth's climate system. The ocean component of heat transport is effected by the thermohaline circulation. Changes in this circulation, and hence latitudinal heat transport, would have a significant effect on global climate. Paleoclimate evidence from the Greenland ice cores and deep sea sediment cores suggests that during much of glacial time the climate system oscillated between two different states. Bimodal equilibrium states of the thermohaline circulation have been demonstrated in climate models. We address the question of the role of the atmospheric hydrological cycle on the global thermohaline circulation and the feedback to the climate system through changes in the ocean's latitudinal heat transport, with a simple coupled ocean-atmosphere energy-salt balance model. Two components of the atmospheric hydrological cycle, i.e., latitudinal water vapor transport and the net flux of water vapor from the Atlantic to the Pacific Ocean appear to play separate roles. If the inter-basin transport is sufficiently large, small changes in water vapor transport over the North Atlantic can effect bifurcation or a rapid transition between two different equilibria in the global thermohaline circulation; maximum difference between the modes occurs in the North Atlantic. If the inter-basin transport is from the Pacific to the Atlantic and sufficiently large, latitudinal vapor transport in the North Pacific controls the bifurcations, with maximum changes occurring in the North Pacific. For intermediate values of inter-basin transport, no rapid transitions occur in either basin. In the regime with vapor flux from the Atlantic to the Pacific, the on mode has strong production of deep water in the North Atlantic and a large flux of heat to the atmosphere from the high latitude North Atlantic. The off mode has strong deep water production in the Southern Ocean and weak production in the North Pacific. Heat transport into the high latitude North Atlantic by the ocean is reduced to about 20% of the on mode value. For estimated values of water vapor transport for the present climate the model asserts that while water vapor transport from the Atlantic to the Pacific Ocean is sufficiently large to make the North Atlantic the dominant region for deep water production, latitudinal water vapor transport is sufficiently low that the thermohaline circulation appears stable, i.e., far from a bifurcation point. This conclusion is supported to some extent by the fact that the high latitude temperature of the atmosphere as recorded in the Greenland ice cores has changed little over the last 9000 years.  相似文献   

15.
在分析沈阳近百年特别是近50 a降水变化规律的基础上,研究了沈阳市降水对水资源的影响。结果表明:沈阳市降水量变化决定水资源变化,从1956年以来水资源总量呈减少趋势,且随着年降水量的变化而变化;地下水变化平缓;地表水资源变化速度比降水变化速度快。同时降水量对辽、浑河的自然径流量影响显著,年际变化剧烈;近10 a沈阳降水量呈减少趋势,将加剧沈阳水资源短缺的矛盾。在对气候进行预估的基础上对水资源的发展趋势做了预估。  相似文献   

16.
利用吉林通榆半干旱区农田站和退化草地站2008年的外场试验观测资料,对比分析了不同土地利用方式对蒸散和地表水分收支的影响。结果表明:从全年来看,尽管两个站点相距仅5 km,但农田站的全年总蒸散量比代表自然土地覆盖状况的退化草地站高28.2 mm;且生长季两种下垫面的蒸散量较为接近,差异主要发生在非生长季。同时,农田站的年水分收支总量为51.1 mm,比退化草地站低35.6%。具体来说,生长季,两个站点的水分收支均有盈余;但在非生长季,退化草地站的水分收支仍有盈余,而农田站则处于水分亏损状态。这说明在半干旱区,代表人为土地利用状况的农田站面临着更大的水分供给压力,人类活动导致的土地利用会加剧该地区的干旱化趋势。
  进一步的分析表明,水分盈余并不代表地表的水分状况良好。从 Priestley-Taylor 系数来看,两个站点的Priestley-Taylor系数均远小于1.0,说明在半干旱区,由于表层土壤水分条件的限制,实际蒸散量远未达到平衡蒸散量,土壤面临着水分供给的压力。其可能的原因是,对半干旱区而言,尽管水分收支有盈余,但是由于土壤沙化严重,土壤孔隙度大,大气降水很容易下渗,并以地下水的形式存储起来,使得表层土壤水分供应反而不足。  相似文献   

17.
As glacial retreat changes the hydrology of Peru's Rio Santa, water demand is growing, pollution is worsening, and competition for water among economic sectors, political jurisdictions and upstream and downstream water users is intensifying. The vulnerability of highland communities, food producers, and poor urban neighborhoods in the Santa watershed in the face of these changes is magnified by inequities in water governance, giving rise to water conflict. Peru's new water regime defines water as an economic good and seeks to centralize control over water. This article analyzes implications of this regime for ensuring equity and managing conflict. It concludes that Peru's water regime is more likely to address equity issues when faced with concerted citizen action.  相似文献   

18.
China's water policies in the past decades have relied heavily on the construction of massive water conservancy projects in the form of dams and reservoirs, water transfer projects, and irrigation infrastructure. These facilities have brought tremendous economic and social benefits but also posed many adverse impacts on the eco-environment and society. With the intensification of water scarcity, China's future water conservancy development is facing tremendous challenge of supporting the continuous economic development while protecting the water resources and the dependent ecosystems. This paper provides an overview of China's water conservancy development, and illustrates the socioeconomic, environmental and ecological impacts. A narrative of attitude changes of the central government towards water conservancy, as well as key measures since the 1950s is presented. The strategic water resources management plan set by the central government in its Document No. 1 of 2011 is elaborated with focus on the three stringent controlling “redlines” concerning national water use, water use efficiency and water pollution and the huge investments poised to finance their implementation. We emphasize that realizing the goals set in the strategic plan requires paradigm shifts of the water conservancy development towards maximizing economic and natural capitals, prioritizing investment to preserve intact ecosystems and to restore degraded ecosystems, adapting climate change, balancing construction of new water projects and rejuvenation of existing projects, and managing both “blue” (surface/groundwater) and “green” water (soil water).  相似文献   

19.
Through an examination of global climate change models combined with hydrological data on deteriorating water quality in the Middle East and North Africa (MENA), we elucidate the ways in which the MENA countries are vulnerable to climate-induced impacts on water resources. Adaptive governance strategies, however, remain a low priority for political leaderships in the MENA region. To date, most MENA governments have concentrated the bulk of their resources on large-scale supply side projects such as desalination, dam construction, inter-basin water transfers, tapping fossil groundwater aquifers, and importing virtual water. Because managing water demand, improving the efficiency of water use, and promoting conservation will be key ingredients in responding to climate-induced impacts on the water sector, we analyze the political, economic, and institutional drivers that have shaped governance responses. While the scholarly literature emphasizes the importance of social capital to adaptive governance, we find that many political leaders and water experts in the MENA rarely engage societal actors in considering water risks. We conclude that the key capacities for adaptive governance to water scarcity in MENA are underdeveloped.  相似文献   

20.
张苏平  胡桂芳  朱平盛 《气象》1996,22(11):3-9
利用1960-1994年胶东地区降水和水资源资料,用变点分析方法将35年分成A,B两个气候段,分析发现从A段到B段降水,立资源明显减少。水资源总量的变化规律和降水变化规律一致,但前者的变化率明显大于后者。地下水变化有一定持续性,气象干旱年的结束不意味着水文枯水年的结束。  相似文献   

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