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981.
Are Kolawole 《Disasters》1987,11(1):59-66
This is a study of the responses of the people of eastern Borno to the twin hazards of drought and of an irrigation project stranded by the recent low level of Lake Chad. The environmental awareness of the people has been much influenced by access to information, particularly radio. There was a perceptual dissonance; drought is discerned as a natural act of God, but lake recession is seen as man-made. There is also a gap between responses perceived as appropriate and actual responses consequent on the constraints imposed by the process of modernization, notably the introduction of the South Chad Irrigation Project (SOP). Traditional response mechanisms involving the norm of reciprocity, the use of community resources, agricultural adaptations and sharing have become relatively insignificant in Borno. These are being replaced by emigration, lake floor cultivation and household diversification 相似文献
982.
Comparing Forecasts of the Global Impacts of Climate Change 总被引:2,自引:0,他引:2
Mendelsohn Robert Williams Larry 《Mitigation and Adaptation Strategies for Global Change》2004,9(4):315-333
This paper utilizes the predictions ofseveral Atmosphere-Ocean GeneralCirculation Models and the Global ImpactModel to create forecasts of the globalmarket impacts from climate change. Theforecasts of market impacts in 2100 varyconsiderably depending on climate scenariosand climate impact sensitivity. The modelsdo concur that tropical nations will behurt, temperate nations will be barelyaffected, and high latitude nations willbenefit. Although the size of theseeffects varies a great deal across models,the beneficial and harmful effects areoffsetting, so that the net impact on theglobe is relatively small in almost alloutcomes. Looking only at market impacts,the forecasts suggest that while the globalnet benefits of abatement are small, thedistribution of damages suggests a largeequity problem that could be addressedthrough a compensation program. The largeuncertainty surrounding these forecastsfurther suggests that continued monitoringof both the climate and impacts isworthwhile. 相似文献
983.
Mizina Svetlana V. Smith Joel B. Gossen Erwin Spiecker Karl F. Witkowski Stephen L. 《Mitigation and Adaptation Strategies for Global Change》1999,4(1):25-41
Agriculture in Kazakhstan is sensitive to climate, and wheat yields could be reduced up to 70% under climate change. With the transition from a socialist economy to a free market economy, decisions are being made now that will affect Kazakhstan's ability to cope with climate change. A team of Kazakh and American researchers examined the cost-effectiveness and barriers to implementations of adaptation options for climate change. Twelve adaptation options that increase flexibility to respond to climate change were identified using a screening matrix. Four options, forecasting pest outbreaks, developing regional centers for preserving genetic diversity of seeds, supporting a transition to a free market, and reducing soil erosion through the use of changed farming practices, were examined. The Adaptation Decision Matrix (ADM) was then applied to estimate benefits using expert judgment (using an arbitrary numerical scale, not monetary values) and benefits estimates were compared to costs to determine cost-effectiveness. The ADM uses subjective measures of how well adaptation options meet policy objectives. Controlling soil erosion was estimated to have the highest benefits, but the high costs of implementation appears to make it relatively cost-ineffective. Supporting a transition to a free market was ranked as the most cost-effective measure, with regional centers second. However, use of different scales to quantify benefits or different weights can result in regional centers being more cost-effective than the transition to a free market. Regional centers was also judged to have fewer barriers to implementation than a transition to a free market. These results will be incorporated in Kazakhstan's National Action Plan. The ADM and other tools are relatively easy to apply, but are quite subjective and difficult to evaluate. The tools can be quite useful by decision makers to analyze advantages and disadvantages between different adaptation options, but should be supplemented with additional, particularly quantitative analysis. 相似文献
984.
This study evaluates the theoretical impact of climate change on yields and water use of two crops with different responses
to increased CO2 and which represent contrasting agricultural systems in Spain. In all cases the simulated effects of a CO2-induced climate change depended on the counteracting effects between higher daily ET rates, shortening of crop growth duration
and changes in precipitation patterns as well as the simulated effects of CO2 on the water use efficiency of the crops. For summer irrigated crops such as maize, the yield reductions and the exacerbated
problems of irrigation water availability simulated with climate change may force the crop out of production in some regions.
For winter dryland crops such as wheat, productivity increased significantly in some regions, suggesting a northward shift
of area suitable for wheat production in future climates. The study considered strategies for improving the efficiency of
water use based on the optimization of crop management decisions in a CO2-driven warmer climate.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
985.
Zhang Yu 《环境科学学报(英文版)》1993,5(2):194-200
The growth process of winter wheat was simulated by CERES-wheat model assuming the daily temperature increase -1, 0,1, 2℃ and daily precipitation increase -20, -10, -5, 0, 5, 10, and 20 percent, respectively. The case study site is Zhenjiang City of Jiangsu Province in the east China. Simulation results show that the impacts of temperature variation on winter wheat is stronger than that of precipitation. Climate warming would speed development rate and shorten phonological period. In general, the adverse effect of climate change on grain yield is greater than that of its beneficial effect, especially when the climate becoming cooler and dryer. The increase of temperature and decrease of precipitation would reduce the plant extractablc soil water content. 相似文献
986.
Amber J. Soja Herman H. Shugart Anatoly Sukhinin Susan Conard Paul W. Stackhouse Jr. 《Mitigation and Adaptation Strategies for Global Change》2006,11(1):75-96
Under current climate change scenarios, temperatures in Siberia are expected to increase, and consequently, fire is also expected
to increase. Potential climate-induced change is difficult to assess in Siberia because ground-based fire data are not complete.
This investigation introduces a method by which potential climate-induced change can be remotely evaluated. Mean fire return
intervals are established for 58 ecosystems across Siberia using eight years of satellite-based area burned data (1995 to
2002). Mean fire return intervals should decrease under current climate change scenarios, however the results do not currently
demonstrate consistent evidence of fire-induced change. The overall boreal forest mean fire return interval is lower than
the published mean, inferring increased fire. Most notably, using satellite data to calculate mean fire return intervals in
individual ecosystems for the entire population of fire is shown to be a viable method by which potential climate-induced
land cover change can be evaluated. 相似文献
987.
Because of concerns with the growing threat of global climate change from increasing emissions of greenhouse gases, the United States and other countries are implementing, by themselves or in cooperation with one or more other nations, climate change projects. These projects will reduce greenhouse gas (GHG) emissions or sequester carbon, and will also result in non-GHG benefits (i.e., environmental, economic, and social benefits). Monitoring, evaluating, reporting, and verifying (MERV) guidelines are needed for these projects to accurately determine their net GHG, and other, benefits. Implementation of MERV guidelines is also intended to: (1) increase the reliability of data for estimating GHG benefits; (2) provide real-time data so that mid-course corrections can be made; (3) introduce consistency and transparency across project types and reporters; and (4) enhance the credibility of the projects with stakeholders. In this paper, we review the issues involved in MERV activities. We identify several topics that future protocols and guidelines need to address, such as: (1) establishing a credible baseline; (2) accounting for impacts outside project boundaries through leakage; (3) net GHG reductions and other benefits; (4) precision of measurement; (5) MERV frequency and the persistence (sustainability) of savings, emissions reduction, and carbon sequestration; (6) reporting by multiple project participants; (7) verification of GHG reduction credits; (8) uncertainty and risk; (9) institutional capacity in conducting MERV; and (10) the cost of MERV. 相似文献
988.
Under the dry weather conditions in the typical steppe region of Inner Mongolia, the diurnal change curve of photosynthetic rate of Aneurolepidium chinense community is a curve of "double peaks" with midday depression. The photosynthetic rate in the morning is height than in the afternoon, which is related to the water condition at that time. The decrease range of community photosynthetic rate at noon is closely correlated with the low air relative humidity and soil moisture, the photosynthetic rate decreases less under better water condition.The instantaneous photosynthetic rate and diurnal net photosynthesis declined in dry condition, but they rised after irrigation or nitrogen-fertilization. Thus irrigation and fertilization is a effective way to improve grasslands and to raise grassland productivity. 相似文献
989.
Wu Kunjun Chen Yuping Li MinghuiInstitute of Zoology Chinese Academy of Sciences Beijing China 《环境科学学报(英文版)》1993,(2)
The cotton bollworm, Heliothis armigera (Hubner) is an important insect species at-tacking many crops. Their performances have been examined at temperatures from 15℃ to 35℃ and relative humidities (RH) between 22.5% and 100%, respectively, in order to assess possible effect of climate in future on its occurrence and infestation. Durations of all developmental stages of the insect shortened with increasing temperature. The temperature favoring population growth ranged from 25℃ to 30℃.Larval duration and adult longevity decreased as relative humidity increased, but development of other stages was independent of RH. At RH of over 64%, their survival rate, egg production and oviposition rate varied a little, and all the population parameters of the insect remained at a relative constant level. 相似文献
990.
Boreal forests represent a biome of the planet whose unique characteristics are changing rapidly under the influence of both
human and natural pressures. These forests hold the key to current and future supply of coniferous industrial wood and at
the same time play a significant role in regulating Earth's climatic system. Expected to be one of the most rapidly impacted
regions of the world by future climate change, the boreal biome has already been substantially affected by global change.
It is likely that if unabated, continued change will lead to impoverishment and degradation of boreal ecosystems, with consequent
loss of vital services upon which human society depends. An improved systems understanding of the functioning of circumpolar
boreal forests is a pressing challenge for boreal forest science and is needed in order to estimate their resilience to perturbations,
to predict likely responses to the changing environment, and to design mitigation strategies. With such understanding, coordinated
international efforts can be focused on developing anticipatory strategies for adaptation to, and mitigation of dangerous
consequences of global change for boreal resources. The International Boreal Forest Research Association (IBFRA) provides
a focus for international research on these issues and serves as a global window for boreal forest science and sustainable
forest management in the boreal region. 相似文献