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31.
Preety M. Bhandari Suruchi Bhadwal Ulka Kelkar 《Mitigation and Adaptation Strategies for Global Change》2007,12(5):919-933
India occupies 2.4% of the world’s geographical area with a large percentage of its land under agriculture. About 228 Million
hectares (Mha) of its geographical area (nearly 69%) fall within the dryland (arid, semi-arid and dry sub-humid) region. Of
the total cultivated area of 142 Mha, major part of agriculture in the country is rainfed, extending to over 97 Mha and constituting
nearly 68% of the net cultivated area, therefore making the agricultural sector vulnerable and exposed to the vagaries of
weather conditions. Climate change adds to this dimension of stress. A strong need is felt for targeting programmes in these
areas that address issues related to employing suitable soil and water conservation measures. In this context this paper seeks
to examine the case for watershed development as an adaptive strategy. An examination of the possibility of fortifying the
existing programme with a view to adapting to expected changes in climate in future is undertaken. Also, the possibility of
watershed development integrating into a suitable mitigation strategy for the country is assessed.
相似文献
Preety M. BhandariEmail: |
32.
U. Martin Persson Christian Azar 《Mitigation and Adaptation Strategies for Global Change》2007,12(7):1277-1304
The possibility of adopting national targets for carbon dioxide (CO2) emissions from tropical deforestation in a future international climate treaty has received increasing attention recently.
This attention has been prompted by proposals to this end and more intensified talks on possible commitments for developing
countries beyond the United Nations Framework Convention on Climate Change Kyoto Protocol. We analyze four main scientific
and political challenges associated with national targets for emissions from tropical deforestation: (1) reducing the uncertainties
in emission inventories, (2) preserving the environmental integrity of the treaty, (3) promoting political acceptance and
participation in the regime, and (4) providing economic incentives for reduced deforestation. We draw the following conclusions.
(1) Although there are large uncertainties in carbon flux from deforestation, these are in the same range as for other emissions
included in the current Kyoto protocol (i.e., non-CO2 GHGs), and they can be reduced. However, for forest degradation processes the uncertainties are larger. A large challenge
lies in building competence and institutions for monitoring the full spectrum of land use changes in developing countries.
(2 and 3) Setting targets for deforestation is difficult, and uncertainties in future emissions imply a risk of creating ‘tropical
hot air’. However, there are proposals that may sufficiently deal with this, and these proposals may also have the advantage
of making the targets more attractive, politically speaking. Moreover, we conclude that while a full carbon accounting system
will likely be politically unacceptable for tropical countries, the current carbon accounting system should be broadened to
include forest degradation in order to safeguard environmental integrity. (4) Doubts can be cast over the possible effect
a climate regime alone will have on deforestation rates, though little thorough analysis of this issue has been made.
相似文献
U. Martin PerssonEmail: |
33.
The coupled SWAP-WOFOST model was used to study the effects of increasing salinity of groundwater, drought and water excess on grass production in The Netherlands. WOFOST simulates crop growth and SWAP simulates transport of water, solutes and heat in the vadose zone. The model was tested using several datasets from field experiments. We applied the models at regional scale where we quantified the impact of various groundwater salinity levels on grass growth and production using historical weather data (1971-2000). The salt concentrations in the subsoil were derived from the National Hydrological Instrument. The results show that salinity effects on grass production are limited. In wet years the excess rainfall will infiltrate the soil and reduce salt water seepage. In a next step we used future weather data for the year 2050, derived from 3 Global Circulation Models. From each model we used data from two CO2 emission scenarios. As expected higher temperatures increased drought stress, however, the production reduction as a result of salt water in the root zone is limited. Salt stress mainly occurred when irrigation was applied with saline water. The increased CO2 concentration in combination with the limited drought stress resulted in increasing simulated actual and potential yields. Overall conclusion for grassland in The Netherlands: drought stress is stronger than stress caused by water excess which on its turn is stronger than salinity stress. Future water demand for irrigation may increase by 11-19% and result in water scarcity if water supply is insufficient. 相似文献
34.
Mikael Hildén 《Journal of Cleaner Production》2011,19(16):1798-1811
All member states of the EU have had to develop climate strategies following the commitment to the UN Framework Convention on Climate Change and the Kyoto Protocol. The evolution of the strategies provides insights into the learning that takes place at the level of policy development and offers material for analysing how ex ante and ex post evaluations have contributed to this learning. In the analysis, Finland is used as a case demonstrating different levels and types of learning, from deeper reframing to political learning. The results show that the full potential of the evaluations has not been utilised, partly because they have been constrained by their mandate. Greater openness and transparency in the policy processes would create favourable conditions for independent evaluations that could provide additional input to the policy processes. This would support social and reflexive learning and allow for greater adaptability. 相似文献
35.
后寨河流域岩溶含水层脆弱性及其对土地利用方式的响应 总被引:1,自引:0,他引:1
由于强烈的溶蚀作用,岩溶地区溶蚀裂隙、管道等高度发育,并相互贯通,形成岩溶区特有的地下、地表“双层空间”结构体系,地下空间成为地下水存储和运移的重要场所。岩溶地区由于土层浅薄或缺失,并且溶蚀裂隙、管道、落水洞、竖井等高度发育,使含水层更易受地表状况的影响,土地利用/覆被变化在很大程度上影响着地下水的水质、水量,岩溶水质的变化能集中反映人类活动胁迫下岩溶含水层脆弱性程度的增加。以典型岩溶单元--贵州普定后寨河流域为例,分析了流域水文地质背景下的岩溶含水层本质脆弱性,结合流域地下河水近20年的水化学资料,分析了含水层脆弱性对土地利用变化的响应。结果显示:土地利用/覆被变化、农业活动、城镇建设及居民活动都对地下水质变化有明显影响。因此,调整土地利用结构,恢复岩溶植被,改善生态环境是保护和改善岩溶水资源的重要途径。 相似文献
36.
37.
为最小化灾后配电网损失量,准确描述完整维修队工作时间(分为路途时间与具体维修时间),依据台风路径对维修队所需路途时间进行分类,并利用期望概率描述具体维修时间的不确定性。建立2阶段分布式鲁棒优化模型,采用CCG算法分析国内某地区配电网算例发现:考虑维修时间不确定性可以有效减少配电网损失量。 相似文献
38.
Sara E. Grineski Aaron B. Flores Timothy W. Collins Jayajit Chakraborty 《Disasters》2020,44(2):408-432
Most disaster studies rely on convenience sampling and ‘after-only’ designs to assess impacts. This paper, focusing on Hurricane Harvey (2017) and leveraging a pre-/post-event sample of Greater Houston households (n=71) in the United States, establishes baselines for disaster preparedness and home structure flood hazard mitigation, explores household-level ramifications, and examines how preparedness and mitigation relate to health effects, event exposures, and recovery. Between 70 and 80 per cent of participants instituted preparedness measures. Mitigation actions varied: six per cent had interior drainage systems and 83 per cent had elevated indoor heating/cooling components. Sixty per cent reported home damage. One-half highlighted allergies and two-thirds indicated some level of post-traumatic stress (PTS). Three-quarters worried about family members/friends. The results of generalised linear models revealed that greater pre- event mitigation was associated with fewer physical health problems and adverse experiences, lower PTS, and faster recovery. The study design exposed the broad benefits of home structure flood hazard mitigation for households after Harvey. 相似文献
39.
Robyn E. Tuerena Claire Mahaffey Sian F. Henley Camille de la Vega Louisa Norman Tim Brand Tina Sanders Margot Debyser Kirstin Dhnke Judith Braun Christian Mrz 《Ambio》2022,51(2):355
Climate change is altering nutrient cycling within the Arctic Ocean, having knock-on effects to Arctic ecosystems. Primary production in the Arctic is principally nitrogen-limited, particularly in the western Pacific-dominated regions where denitrification exacerbates nitrogen loss. The nutrient status of the eastern Eurasian Arctic remains under debate. In the Barents Sea, primary production has increased by 88% since 1998. To support this rapid increase in productivity, either the standing stock of nutrients has been depleted, or the external nutrient supply has increased. Atlantic water inflow, enhanced mixing, benthic nitrogen cycling, and land–ocean interaction have the potential to alter the nutrient supply through addition, dilution or removal. Here we use new datasets from the Changing Arctic Ocean program alongside historical datasets to assess how nitrate and phosphate concentrations may be changing in response to these processes. We highlight how nutrient dynamics may continue to change, why this is important for regional and international policy-making and suggest relevant research priorities for the future.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01673-0. 相似文献
40.
Karley Campbell Ilkka Matero Christopher Bellas Thomas Turpin-Jelfs Philipp Anhaus Martin Graeve Francois Fripiat Martyn Tranter Jack Christopher Landy Patricia Sanchez-Baracaldo Eva Leu Christian Katlein C. J Mundy Sren Rysgaard Letizia Tedesco Christian Haas Marcel Nicolaus 《Ambio》2022,51(2):318
Sea ice continues to decline across many regions of the Arctic, with remaining ice becoming increasingly younger and more dynamic. These changes alter the habitats of microbial life that live within the sea ice, which support healthy functioning of the marine ecosystem and provision of resources for human-consumption, in addition to influencing biogeochemical cycles (e.g. air–sea CO2 exchange). With the susceptibility of sea ice ecosystems to climate change, there is a pressing need to fill knowledge gaps surrounding sea ice habitats and their microbial communities. Of fundamental importance to this goal is the development of new methodologies that permit effective study of them. Based on outcomes from the DiatomARCTIC project, this paper integrates existing knowledge with case studies to provide insight on how to best document sea ice microbial communities, which contributes to the sustainable use and protection of Arctic marine and coastal ecosystems in a time of environmental change.Supplementary InformationThe online version contains supplementary material available at 10.1007/s13280-021-01658-z. 相似文献