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1.
自然植被对气候变化响应的研究:综述   总被引:12,自引:0,他引:12  
植被-气候关系的研究已经超越了植被地理学、植被生态学的研究范围,而成为全球变化研究的核心内容之一,从而受到地理学家、生态学家等的广泛关注,并开展了大量的研究。本文概述了过去、现在和未来自然植被对气候变化响应研究的主要进展,阐述了自然植被响应气候变化,特别是未来全球气候变化的基本的可能结果。  相似文献   

2.
The EPIC (Erosion Productivity Impact Calculator) crop model, developed by scientists of the United States Department of Agriculture (USDA), has been successfully applied to the study of erosion, water pollution, crop growth and production in the US but is yet to be introduced for serious research purposes in other countries or regions. This paper reports on the applicability of the EPIC 8120 crop model for the assessment of the potential impacts of climate variability and climate change on crop productivity in sub‐Saharan West Africa, using Nigeria as the case study. Among the crops whose productivity has been successfully simulated with this model are five of West Africa's staple food crops: maize, millet, sorghum (guinea corn), rice and cassava. Thus, using the model, the sensitivities of maize, sorghum and millet to seasonal rainfall were demonstrated with coefficients of correlation significant at over 98 per cent confidence limits. The validation tests were based on a comparison of the observed and the model‐generated yields of rice and maize. The main problems of validation relate to the multiplicity of crop varieties with contrasting performances under similar field conditions. There are also the difficulties in representing micro‐environments in the model. Thus, some gaps appear between the observed and the simulated yields, arising from data or model deficiencies, or both. Based on the results of the sensitivity and validation tests, the EPIC crop model could be satisfactorily employed in assessing the impacts of and adaptations to climate variability and climate change. Its use for the estimation of production and the assessment of vulnerabilities need to be pursued with further field surveys and field experimentation.  相似文献   

3.
全球气候变化下中国农业的脆弱性与适应对策   总被引:120,自引:3,他引:120  
蔡运龙 Smit.  B 《地理学报》1996,51(3):202-212
全球气候变化问题虽然还存在某些不确定性,但已得到广泛认同,对气候条件颇为敏感的农业将受影响,主要效应可概括为:(1)农业地理限制的变动;(2)作物产量的变化;(3)对农业系统的冲击。中国农业对气候变化与波动尤其敏感,加之人口压力进一步加大和农业资源已有紧缺,粮食自给的能力将受到严重威胁,必须充分重视适应和调整对策的研究,变动性与不确定性是气候的固有特征,在评价全球气候变化对农业的影响时应该认识到这  相似文献   

4.
温室气体诱导的渐变气候效应   总被引:1,自引:0,他引:1  
赵凤生  石广玉 《地理学报》1995,50(5):430-438
本文设计了一个能量平衡模式和改进的箱室扩散海洋模式的耦合模式,模拟了大气中CO2浓度突然加倍和近百年来由于大气中温室气体浓度增加引起的全球地表气温变化,说细地讨论了海洋对全球气温变化的延缓作用,并对下一世纪大气中CO2浓度变化春诱导的全球地表温变化进行了数值公式。  相似文献   

5.
Glacier advance and recession are considered key indicators of climate change. Understanding the relationship between climatic variations and glacial responses is crucial. Here, we apply archival digital photogrammetry to reconstruct the decadal scale glacial history of an unmonitored Alpine valley glacier, the Haut Glacier d'Arolla, Switzerland, and we use the data generated to explore the linkages between glacier recession and climate forcing. High precision digital elevation models were derived. They show continual recession of the glacier since 1967, associated with long‐term climatic amelioration but only a weak reaction to shorter‐term climatic deterioration. Glacier surface velocity estimates obtained using surface particle tracking showed that, unlike for most Swiss glaciers during the late 1970s and early 1980s, ice mass flux from the accumulation zone was too low to compensate for the effects of glacier thinning and subsequent snout recession, especially during the rapid warming that occurred through the 1980s. The results emphasise the dangers of inferring glacier response to climate forcing from measurements of the terminus position only and the importance of using remote sensing methods as an alternative, especially where historical imagery is available.  相似文献   

6.
Heightened public concern, pending federal legislation, and calls for an international treaty to reduce emissions of greenhouse gases have placed pressure on resource planners to mitigate the causes and impacts of anthropogenic climate change despite uncertainty over its timing and magnitude. Traditional resource planning, however, is predicated on the assumption that future environmental conditions will emulate the past, and is based on local and national, rather than global, objectives. The threat of global warming calls for a new paradigm of resource planning, including expanded sensitivity analysis, incremental response as the threat evolves, an expanded range of adjustments, and planning in a global context.  相似文献   

7.
论工业变化的综合研究:以澳大利亚制造业为例   总被引:4,自引:0,他引:4  
李小建 《地理学报》1991,46(3):289-299
80年代以来,国际工业地理学界采取不同的方法途径对工业变化进行研究。本文在分析这些方法的基础上,提出将工业组织变化与工业区域变化、工业结构变化加以结合,以弥补在工业区域和结构变化研究中忽视组织决策因素,在工业组织变化研究中忽视把区域作为一个整体。基于大量统计数据和本人实地调查资料,本文应用这种综合方法研究了70年代以来澳大利亚的工业变化。  相似文献   

8.
Long‐term observations of partly debris‐covered glaciers have allowed us to assess the impact of supra‐glacial debris on volumetric changes. In this paper, the behaviour of the partially debris‐covered, 3.6 km2 tongue of Pasterze Glacier (47°05′N, 12°44′E) was studied in the context of ongoing climate changes. The right part of the glacier tongue is covered by a continuous supra‐glacial debris mantle with variable thicknesses (a few centimetres to about 1 m). For the period 1964–2000 three digital elevation models (1964, 1981, 2000) and related debris‐cover distributions were analysed. These datasets were compared with long‐term series of glaciological field data (displacement, elevation change, glacier terminus behaviour) from the 1960s to 2006. Differences between the debriscovered and the clean ice parts were emphasised. Results show that volumetric losses increased by 2.3 times between the periods 1964–1981 and 1981–2000 with significant regional variations at the glacier tongue. Such variations are controlled by the glacier emergence velocity pattern, existence and thickness of supra‐glacial debris, direct solar radiation, counter‐radiation from the valley sides and their changes over time. The downward‐increasing debris thickness is counteracting to a compensational stage against the common decrease of ablation with elevation. A continuous debris cover not less than 15 cm in thickness reduces ablation rates by 30–35%. No relationship exists between glacier retreat rates and summer air temperatures. Substantial and varying differences of the two different terminus parts occurred. Our findings clearly underline the importance of supra‐glacial debris on mass balance and glacier tongue morphology.  相似文献   

9.
本文以广东省47个测站近40年来6~9月降水量、平均气温、总日照时数和一些主要农作物逐年单产量资料为基础,用主分量分析、周期回归等方法,分析广东全省性的气候时空变化特征;分析一些主要农作物逐年单产的变化规律.用多元逐步回归分析方法探讨了广东全省性气候变化与同期及后期(1~3年)主要农作物单产量间的关系并作了预报.  相似文献   

10.
采用土地利用经济生态位模型、土地利用程度综合指数模型和生态服务价值评价方法,结合长株潭区域1996—2005年的土地利用更新调查数据,研究该区域生态系统对土地利用变化的响应。结果表明:(1)长株潭城市群非农用地对农用地的捕获力呈逐年增强的趋势,土地利用整体上朝利用强度增大、广度增加的方向发展,而区域生态系统服务价值量则呈现逐年下降的趋势;(2)长株潭城市群生态服务功能价值量分别与土地利用生态位差值和土地利用综合指数呈显著的负相关关系,其中与土地利用综合指数相关度最高;(3)在推进新型城市化过程中,控制非农用地的外延扩展,增加农地转用的生态补偿,减小土地利用的经济生态位差值能有效抑制农地的快速减少,促进区域“经济”与“生态”的协调发展。  相似文献   

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