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1.
马占云  熊伟  林而达 《安徽农业科学》2009,37(13):6053-6055
政府间气候变化专业委员会(IPCC)第4次评估指出许多自然系统正在受到气候变化,特别是温度升高的影响。同时常规能源使用所带来的环境问题日益严重,生物质能以其特性成为可替代能源。我国农作物秸秆是主要的生物质能的来源,对未来情景下作物秸秆的准确模拟非常重要。笔者在地理信息技术(GIS)的支持下,选用IPCC提供的未来情景,以GIS相关技术支持CERES-Maize作物模型完成了玉米秸秆产量模拟。结果显示玉米秸秆平均单产呈增产趋势,但全国分布不均,很多区域都是增、减幅在0~30%范围内变化。而且,气候变化对A2情景的影响变幅要大于B2情景,对灌溉玉米的正面影响大于雨养玉米。  相似文献   

2.
Global biodiversity scenarios for the year 2100   总被引:18,自引:0,他引:18  
Scenarios of changes in biodiversity for the year 2100 can now be developed based on scenarios of changes in atmospheric carbon dioxide, climate, vegetation, and land use and the known sensitivity of biodiversity to these changes. This study identified a ranking of the importance of drivers of change, a ranking of the biomes with respect to expected changes, and the major sources of uncertainties. For terrestrial ecosystems, land-use change probably will have the largest effect, followed by climate change, nitrogen deposition, biotic exchange, and elevated carbon dioxide concentration. For freshwater ecosystems, biotic exchange is much more important. Mediterranean climate and grassland ecosystems likely will experience the greatest proportional change in biodiversity because of the substantial influence of all drivers of biodiversity change. Northern temperate ecosystems are estimated to experience the least biodiversity change because major land-use change has already occurred. Plausible changes in biodiversity in other biomes depend on interactions among the causes of biodiversity change. These interactions represent one of the largest uncertainties in projections of future biodiversity change.  相似文献   

3.
Abrupt climate change   总被引:4,自引:0,他引:4  
Large, abrupt, and widespread climate changes with major impacts have occurred repeatedly in the past, when the Earth system was forced across thresholds. Although abrupt climate changes can occur for many reasons, it is conceivable that human forcing of climate change is increasing the probability of large, abrupt events. Were such an event to recur, the economic and ecological impacts could be large and potentially serious. Unpredictability exhibited near climate thresholds in simple models shows that some uncertainty will always be associated with projections. In light of these uncertainties, policy-makers should consider expanding research into abrupt climate change, improving monitoring systems, and taking actions designed to enhance the adaptability and resilience of ecosystems and economies.  相似文献   

4.
气候和土地利用变化对松华坝流域水资源的相对作用研究   总被引:1,自引:0,他引:1  
以云南省滇池松华坝流域为研究对象,利用分布式水文模型(SWAT)探讨了气候和土地利用变化对河道径流和总氮的影响及对水资源变化的相对作用,模拟分析了气候变化背景下两者相对作用程度的变化。结果表明:气候是流域内河道径流变化的主要原因,贡献率为63.1%~96.6%。土地利用对河道径流变化的影响整体上偏小,但是差异较大;在降雨减少或不变时土地利用的贡献率为12.2%~36.9%,在降雨增加时贡献率为3.4%~5.2%。从土地利用类型的变化来看,耕地减少和草地增加可增加河道径流量,反之则减少。气候和土地利用变化都是影响水体总氮变化的主要原因,贡献率分别为68.2%和68.5%,而两者对水体总氮的影响在不同时期差异较大。当总氮数量变化较大,或者减少量超过40%时,土地利用的贡献率比较大,而当总氮负荷增加或者减少幅度较小时,气候的贡献率比较大。土地利用类型和总氮变化量之间的相关性分析表明,耕地面积与总氮变化显著正相关(r=0.814),草地面积与总氮变化显著负相关(r=-0.895),而林地面积与总氮变化相关性不显著。  相似文献   

5.
The seasons, global temperature, and precession   总被引:1,自引:0,他引:1  
Analysis of instrumental temperature records beginning in 1659 shows that in much of the world the dominant frequency of the seasons is one cycle per anomalistic year (the time from perihelion to perihelion, 365.25964 days), not one cycle per tropical year (the time from equinox to equinox, 365.24220 days), and that the timing of the annual temperature cycle is controlled by perihelion. The assumption that the seasons were timed by the equinoxes has caused many statistical analyses of climate data to be badly biased. Coherence between changes in the amplitude of the annual cycle and those in the average temperature show that between 1854 and 1922 there were small temperature variations, probably of solar origin. Since 1922, the phase of the Northern Hemisphere coherence between these quantities switched from 0 degrees to 180 degrees and implies that solar variability cannot be the sole cause of the increasing temperature over the last century. About 1940, the phase patterns of the previous 300 years began to change and now appear to be changing at an unprecedented rate. The average change in phase is now coherent with the logarithm of atmospheric CO(2) concentration.  相似文献   

6.
Climate extremes: observations, modeling, and impacts   总被引:18,自引:0,他引:18  
One of the major concerns with a potential change in climate is that an increase in extreme events will occur. Results of observational studies suggest that in many areas that have been analyzed, changes in total precipitation are amplified at the tails, and changes in some temperature extremes have been observed. Model output has been analyzed that shows changes in extreme events for future climates, such as increases in extreme high temperatures, decreases in extreme low temperatures, and increases in intense precipitation events. In addition, the societal infrastructure is becoming more sensitive to weather and climate extremes, which would be exacerbated by climate change. In wild plants and animals, climate-induced extinctions, distributional and phenological changes, and species' range shifts are being documented at an increasing rate. Several apparently gradual biological changes are linked to responses to extreme weather and climate events.  相似文献   

7.
全球气候变化下中国农田土壤碳库未来变化   总被引:5,自引:0,他引:5  
农田土壤碳库对缓解气候变化、保证粮食安全具有重要作用。日益加剧的气候变化对农田土壤有机碳库演变的潜在影响受到广泛关注。全球气候变化所带来的温度、降雨和大气二氧化碳(CO2)浓度的改变,会通过影响净初级生产力(NPP)、外源碳投入和有机碳分解速率等因素改变生态系统碳循环过程。另外,气候变化也会通过改变土地利用方式和种植制度等农业措施改变生态系统碳循环。综述国内外农田土壤碳库演变对气候变化影响的研究成果表明,到21世纪末,中国气温将会升高3.9-6.0℃,降水有望增加9%-11%。至2050年,气温和降水的变化会造成中国农田系统碳投入相比1980年降低2.3%-10%(小麦、玉米和水稻平均值)。相反,在综合考虑CO2浓度升高的协同作用后,2050年中国农田系统碳投入相比1990年前将会增加13%-22%(平均年增长率0.2%-0.4%)。模型预测显示,至2020、2050和2080年,中国旱地0-30 cm土层有机碳在CO2低排放情景下分别会损失2.7、6.0和 7.8 tC·hm-2,在CO2高排放情景下分别会损失2.9、6.8和8.2 tC·hm-2,大概占1980年农田土壤碳的4.5%、10.5%和12.7%。综合碳投入和排放对农田土壤碳库的整体影响来看,21世纪末期中国农田土壤有机碳库含量较1980年会下降10%左右,但如果采取相应的管理措施,可有效抑制农田土壤碳库的降低甚至提高,如农田系统碳投入以每年1%的速度增加时,土壤碳库会在21世纪末增加两倍。目前的研究结果显示,气候变化是否会强烈影响农田土壤碳库依然有很大的不确定因素,其对固碳效应正面和负面影响相互抵消后成为碳源还是碳汇说法不一。因此,在采取缓解气候变化、增加农田土壤固碳的措施的同时,还需加强农田土壤碳库未来变化趋势的研究和探索,为中国政策框架的决定以及未来气候变化谈判提供可靠的科学依据。  相似文献   

8.
Ecosystem service supply and vulnerability to global change in Europe   总被引:12,自引:0,他引:12  
Global change will alter the supply of ecosystem services that are vital for human well-being. To investigate ecosystem service supply during the 21st century, we used a range of ecosystem models and scenarios of climate and land-use change to conduct a Europe-wide assessment. Large changes in climate and land use typically resulted in large changes in ecosystem service supply. Some of these trends may be positive (for example, increases in forest area and productivity) or offer opportunities (for example, "surplus land" for agricultural extensification and bioenergy production). However, many changes increase vulnerability as a result of a decreasing supply of ecosystem services (for example, declining soil fertility, declining water availability, increasing risk of forest fires), especially in the Mediterranean and mountain regions.  相似文献   

9.
This paper examines farmer intentions to adapt to global climate change by analyzing responses to a climate change scenario presented in a survey given to large-scale farmers (n = 4778) across the US Corn Belt in 2012. Adaptive strategies are evaluated in the context of decision making and farmers’ intention to increase their use of three production practices promoted across the Corn Belt: no-till farming, cover crops, and tile drainage. This paper also provides a novel conceptual framework that bridges a typology of adaptation with concepts that help predict intentionality in behavior change models. This conceptual framework was developed to facilitate examination of adaptive decision making in the context of agriculture. This research effort examines key factors that influence farmers’ intentions to increase their use of the practices evaluated given a climate change scenario. Twenty-two covariates are examined across three models developed for no-till farming, cover crops, and tile drainage. Findings highlight that farmers who believed they should adjust their practices to protect their farm from the negative impacts of increased weather variability were more likely to indicate that they would increase their use of each of the practices in response to climate change. Additionally, visiting with other farmers to observe their practices was positively associated with farmers’ intentions to increase their use of the adaptive strategies examined. Farmers who were currently using no-till farming, cover crops, and tile drainage were also more likely to plan to increase their use of these practices in response to increased weather variability associated with climate change. However, farmers who reported high levels of confidence in their current practices were less likely to plan on changing their use of these practices in response to climatic changes.  相似文献   

10.
Ecosystems change in response to factors such as climate variability, invasions, and wildfires. Most records used to assess such change are based on short-term ecological data or satellite imagery spanning only a few decades. In many instances it is impossible to disentangle natural variability from other, potentially significant trends in these records, partly because of their short time scale. We summarize recent studies that show how paleoecological records can be used to provide a longer temporal perspective to address specific conservation issues relating to biological invasions, wildfires, climate change, and determination of natural variability. The use of such records can reduce much of the uncertainty surrounding the question of what is "natural" and thereby start to provide important guidance for long-term management and conservation.  相似文献   

11.
Range shifts and adaptive responses to Quaternary climate change   总被引:2,自引:0,他引:2  
Tree taxa shifted latitude or elevation range in response to changes in Quaternary climate. Because many modern trees display adaptive differentiation in relation to latitude or elevation, it is likely that ancient trees were also so differentiated, with environmental sensitivities of populations throughout the range evolving in conjunction with migrations. Rapid climate changes challenge this process by imposing stronger selection and by distancing populations from environments to which they are adapted. The unprecedented rates of climate changes anticipated to occur in the future, coupled with land use changes that impede gene flow, can be expected to disrupt the interplay of adaptation and migration, likely affecting productivity and threatening the persistence of many species.  相似文献   

12.
北方森林生态系统对全球气候变化的响应研究进展   总被引:1,自引:1,他引:1  
北方森林是地球上第2大生物群区,约占陆地森林面积的30%,提供了从局地到全球的生态系统服务功能。1850年以来,全球性持续升温不断显现,2000—2050年全球至少升高2 ℃,甚至更高。预计到2100年,北方森林区冬季平均温度将升高1.3~6.3 ℃。与此同时,几乎所有的北方森林生态系统功能都将会受到影响,尤其是近几十年来,该区域发生了很多与温度升高相关的潜在生态响应。本文从碳循环、生物多样性、干旱化和林火发生频率以及冻土变化等方面具体综述了北方森林生态系统对于全球气候变化的响应。响应结果如下:1)气候变化对于北方森林碳循环动态的影响是极其复杂的,迄今为止并没有达成共识, 分解对于温度的反应敏感程度至今仍存在很多不确定性。2)动物、植物和微生物(真菌)均对气候变化产生了一定的响应,表现为动物和植物的分布区进一步北移,但真菌的多样性和生产力响应机制尚无法确定。3)北方森林区随气候变化表现为进一步的干旱化和林火发生明显增加。4)北方森林区与冻土伴生,冻土随气候变暖表现出了面积缩小和活动层扩大的趋势。可见,北方森林对气候变化响应明显,尽管到目前为止有些响应机制尚不清楚,但变化趋势十分明显。本文旨在为北方森林的经营和管理提供基础数据和技术支持,实现北方森林的可持续经营。   相似文献   

13.
大气环境变化导致水稻品质总体变劣   总被引:7,自引:0,他引:7  
气候变化将改变作物的生长环境,进而影响作物产量和品质。气候变化对重要粮食作物水稻产量形成的影响已有很多报道,但对同样重要的品质研究较少。在简要介绍实验平台基础上,本文总结了气候变化对水稻品质影响的研究进展。品质性状分为加工、外观、蒸煮/食味、营养和饲用品质,气候变化包括大气CO2浓度升高、近地层O3浓度增高和气温升高等,本文重点聚焦大气组分变化及其与高温的互作。已有文献表明,气候变化对水稻品质的影响尚存在诸多不确定性,但本文也发现了一些重要趋势,这些趋势多为不利的变化。高CO2浓度、高O3浓度或高温环境下生长的水稻表现出垩白增加、碎米增多的趋势;高CO2浓度导致稻米蛋白质和多种元素浓度下降,但食味品质可能变优;臭氧胁迫水稻的食用和饲用品质均有变劣趋势。目前这方面认知多来自于单一气候因子的影响研究,但已有少量研究观察到CO2与温度或O3之间的交互作用;另外,水稻品质性状对气候变化的响应可能还受熏蒸方式、基因型和施肥量等影响。未来这一领域需继续利用不同尺度的试验平台验证已有趋势并拓展研究内容,在这基础上评估气候变化因子之间以及与其他因子的交互作用,重点揭示这些交互作用的内在机制,以便开发出真正适应未来气候变化的稻作生产技术。  相似文献   

14.
青藏高原作为全球气候变化的启动器和调节器,在全球气候变化研究中备受关注。研究全球变暖背景下的青藏高原气候变化以及植被的响应特征,对于推进该区域气候变化研究具有重要意义,目前已有不少该方面的研究报道,但大多局限于对个别气候因素或个别植被响应的描述,缺乏对多种气候因素的综合概括和对植被响应区域差异方面的系统概括。该研究首先总结了青藏高原多个气候参数(气温、降水、积雪、日照辐射、水热通量等)的变化特征;然后归纳了在气候变化背景下,高原植被特征参数(绿度、物候、生产力、碳源/汇)对气候变化响应的规律;最后针对4个环境脆弱区,包括藏北、三江源、环青海湖、林芝,进行了植被变化气候响应特征的讨论。基于以上概述,分析了青藏高原植被气候变化响应研究方面存在的问题,对未来的研究方向进行了展望。  相似文献   

15.
Body size plays a critical role in mammalian ecology and physiology. Previous research has shown that many mammals became smaller during the Paleocene-Eocene Thermal Maximum (PETM), but the timing and magnitude of that change relative to climate change have been unclear. A high-resolution record of continental climate and equid body size change shows a directional size decrease of ~30% over the first ~130,000 years of the PETM, followed by a ~76% increase in the recovery phase of the PETM. These size changes are negatively correlated with temperature inferred from oxygen isotopes in mammal teeth and were probably driven by shifts in temperature and possibly high atmospheric CO(2) concentrations. These findings could be important for understanding mammalian evolutionary responses to future global warming.  相似文献   

16.
Status and improvements of coupled general circulation models   总被引:1,自引:0,他引:1  
Grassl H 《Science (New York, N.Y.)》2000,288(5473):1991-1997
Coupled general circulation models (CGCMs) integrate our knowledge about atmospheric and oceanic circulation. Different versions of CGCMs are used to provide a better understanding of natural climate variability on interannual and decadal time scales, for extended weather forecasting, and for making seasonal climate scenario projections. They also help to reconstruct past climates, especially abrupt climate change processes. Model intercomparisons, new test data (mainly from satellites), more powerful computers, and parameterizations of atmospheric and oceanic processes have improved CGCM performance to such a degree that the model results are now used by many decision-makers, including governments. They are also fundamental for the detection and attribution of climate change.  相似文献   

17.
胡亚南  刘颖杰 《中国农业科学》2013,46(15):3105-3114
【目的】研究东北地区春玉米适种区域及其生育期、产量对气候变化的响应。【方法】基于气候模式RegCM4输出的未来RCP4.5新气候情景逐日资料,采用经验频率法预测80%保证率下2011—2050年中国东北地区早、中、晚熟型春玉米种植区域时空变化,同时结合作物模型DSSAT4.5对黑龙江省晚熟品种的生育期、产量变化特征及该省因气候变化而新增的晚熟品种可能种植区内晚熟玉米的适种性进行模拟评估。【结果】RCP4.5情景下,2011—2050年东北三省≥10℃的积温呈增加趋势,早、中、晚熟型玉米品种种植界限均有不同程度的北扩或东移,可能种植范围扩大。黑龙江省2011—2050年间晚熟玉米新增可能种植区域内适宜种植晚熟品种;气候变化对原有种植区内晚熟品种生殖生长期的影响程度大于对营养生长期的影响,全生育期天数平均缩短2—11 d;产量变化存在明显空间差异,不考虑CO2肥效作用和考虑CO2肥效作用两种方案下的产量变化范围均介于±20%以内,但考虑CO2肥效作用时的产量较高。【结论】因气候条件变化而新增的春玉米种植区域的适种性需要综合考虑多方面因素来评估。未来40a玉米全生育期天数变化主要源于生殖生长期缩短,大气中CO2浓度增加带来的肥效作用可抵消一部分因温度升高产生的对玉米产量形成的不利影响。  相似文献   

18.
Responses of species to climate change are extremely variable, perhaps because of climate-related changes to interactions among species. We show that temperature-related changes in the dependence of the butterfly Aricia agestis on different larval host plants have facilitated rapid range expansion. Historically, the butterfly was largely restricted to a single plant species, Helianthemum nummularium, but recent warmer conditions have enabled the butterfly to increasingly use the more widespread plant species Geranium molle. This has resulted in a substantial increase in available habitat and rapid range expansion by the butterfly (79 kilometers northward in Britain in 20 years). Interactions among species are often seen as constraints on species' responses to climate change, but we show that temperature-dependent changes to interspecific interactions can also facilitate change.  相似文献   

19.
Geographical clines in genetic polymorphisms are widely used as evidence of climatic selection and are expected to shift with climate change. We show that the classic latitudinal cline in the alcohol dehydrogenase polymorphism of Drosophila melanogaster has shifted over 20 years in eastern coastal Australia. Southern high-latitude populations now have the genetic constitution of more northerly populations, equivalent to a shift of 4 degrees in latitude. A similar shift was detected for a genetically independent inversion polymorphism, whereas two other linked polymorphisms exhibiting weaker clinal patterns have remained relatively stable. These genetic changes are likely to reflect increasingly warmer and drier conditions and may serve as sensitive biomarkers for climate change.  相似文献   

20.
Rice is one of the most important grain crops in Northeast China (NEC) and its cultivation is sensitive to climate change. This study aimed to explore the spatio-temporal changes in the NEC rice planting area over the period of 1980–2010 and to analyze their relationship to climate change. To do so, the CLUE-S (conversion of land use and its effects at small region extent) model was first updated and used to simulate dynamic changes in the rice planting area in NEC to understand spatio-temporal change trends during three periods: 1980–1990, 1990–2000 and 2000–2010. The changing results in individual periods were then linked to climatic variables to investigate the climatic drivers of these changes. Results showed that the NEC rice planting area expanded quickly and increased by nearly 4.5 times during 1980–2010. The concentration of newly planted rice areas in NEC constantly moved northward and the changes were strongly dependent on latitude. This confirmed that climate change, increases in temperature in particular, greatly influenced the shift in the rice planting area. The shift in the north limit of the NEC rice planting area generally followed a 1°C isoline migration pattern, but with an obvious time-lag effect. These findings can help policy makers and crop producers take proper adaptation measures even when exposed to the global warming situation in NEC.  相似文献   

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