Market opportunities do not explain the ability of herders to meet livelihood objectives over winter on the Mongolian Plateau

Drylands under pastoral land use are considered one of the most vulnerable social-ecological systems to global climate change, but the herders' abilities to adapt to the different extreme weather events have received little attention in the drylands. Herders on the Mongolian Plateau(MP; including Inner Mongolia Autonomous Region of China and Mongolia), have had a long history of adapting climatic variability and extreme weather events. However, it is unclear how changes such as increased levels of infrastructure and market integration affect the ability of herders to achieve the key livelihood objectives: the minimisation of the death and abortion rates of livestock in the winter. Here, we used remotely sensed and household survey data to map, model and explore the climate exposure and sensitivity of herders in the settled area(Inner Mongolia of China) and nomadic area(Mongolia) in the winter of 2012–2013. We aimed to quantify the multi-scaled characteristics of both climate exposure and sensitivity through the lens of key adaptive strategies utilized by herders. Our results showed that the higher levels of infrastructure and market integration, and the lower levels of remoteness on the MP did not increase the herders' ability to achieve the key livelihood objectives. Our results also suggested that exposure to the snow that is comparatively greater than the long-term average(cumulative exposure) may be more important in determining the social-ecological vulnerability than absolute exposure. We suggested that neither the risk management strategies available to these herders, nor the demographic variables, could compensate for the mode of production governing the pastoral systems. Our study could provide further evidence for the complex and scaled nature of climate exposure and sensitivity, and the results imply that any analysis of the relationship among exposure, sensitivity and vulnerability of pastoral households to climate change in the drylands will require a multi-scaled and interdisciplinary approach.     

阿克苏河流域公众气候变化感知及适应措施选择的差异分析

通过调查问卷方式,结合科学监测数据,分析阿克苏河流域公众对气候变化及其影响的感知及适应对策选择倾向,并比较了流域内不同地区、职业及学历居民的感知差异与对策选择差异。结果表明：① 阿克苏河流域绝大多数居民认为,气候已发生变化,且变化时间在20世纪80年代后,居民在气候变化感知中所体现的地区差异较明显。② 阿克苏河流域多数居民认为,当地“山区雪冰融化加速”、“自然灾害增多”、“播种期提前”,不同属性居民对其感知差异不明显;对于“河流水量变化”,居民的感知存在不确定性,并存在明显的区域差异。③ 农业系统自身调整型措施、基础设施建设型措施和提高农业水资源利用效率型措施易被居民接受。④ 阿克苏地区不同流域、职业及学历的居民在适应对策选择中存在一定差异,其中,中游居民、非农业者以及中高等学历者的应对措施倾向较为积极。
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黄土高原气候响应全球变化的敏感区

收集黄土高原区域近40 a各主要气候要素变化资料并利用Petitt方法计算变点,滑动t检验气候变点或转折点,以分析判断黄土高原对全球气候变化响应的敏感性及敏感区域。结果表明:黄土高原降水、气温、土壤干旱、气候生产力等气候要素对全球气候变化响应的敏感区主要集中在高原中部附近,敏感区要素变化以2~4 a的年际振荡为主。     

沙尘源区示踪方法及分布研究进展

沙尘物质对全球气候变化具有重要影响,其源区示踪已成为全球环境变化研究的热点问题之一.从矿物学、元素地球化学、同位素地球化学等方面综述了国内外对沙尘源区示踪方法的研究现状,同时介绍了现代尘暴事件、中国北方黄土、冰岩芯和深海沉积物沙尘源区分布的研究进展情况,并对研究中存在的问题进行了讨论,希望对这方面研究有所裨益.     

1960-2008年黑河流域地表干湿状况的时空变化分析

利用1960-2008年黑河流域16个气象站的逐日气象资料,采用FAO推荐的Penman-Monteith公式计算最大可能蒸散量,进而计算该流域的湿润指数,对地表干湿状况的时空变化特征及其主要影响因素进行分析。结果表明：黑河流域及其上、中、下游地区的湿润指数总体呈上升趋势,地表湿润状况有所改善,且湿润指数的年际波动性较明显,变异系数分别为14.97%、13.63%、25.47%、37.72%。除下游地区外,夏季的湿润指数变化速率最快,冬季的变化速率最慢;春季,黑河流域地表以变干趋势为主,其他季节均以变湿趋势为主。影响黑河流域地表干湿状况的主要因素是降水量,其他气候因子的变化对地表干湿状况起增强或削弱作用。     

Climate change impacts on plant canopy architecture: implications for pest and pathogen management

Climate change influences on pests and pathogens are mainly plant-mediated. Rising carbon dioxide and temperature and altered precipitation modifies plant growth and development with concomitant changes in canopy architecture, size, density, microclimate and the quantity of susceptible tissue. The modified host physiology and canopy microclimate at elevated carbon dioxide influences production, dispersal and survival of pathogen inoculum and feeding behaviour of insect pests. Elevated temperature accelerates plant growth and developmental rates to modify canopy architecture and pest and pathogen development. Altered precipitation affects canopy architecture through either drought or flooding stress with corresponding effects on pests and pathogens. But canopy-level interactions are largely ignored in epidemiology models used to project climate change impacts. Nevertheless, models based on rules of plant morphogenesis have been used to explore pest and pathogen dynamics and their trophic interactions under elevated carbon dioxide. The prospect of modifying canopy architecture for pest and disease management has also been raised. We offer a conceptual framework incorporating canopy characteristics in the traditional disease triangle concept to advance understanding of host-pathogen-environment interactions and explore how climate change may influence these interactions. From a review of recent literature we summarize interrelationships between canopy architecture of cultivated crops, pest and pathogen biology and climate change under four areas of research: (a) relationships between canopy architecture, microclimate and host-pathogen interaction; (b) effect of climate change related variables on canopy architecture; (c) development of pests and pathogens in modified canopy under climate change; and (d) pests and pathogen management under climate change.     

气候变暖对典型草原区降水时空分布格局的影响

立足于全球变暖对内蒙古典型草原区降水时空变化影响的研究,预测全球变化可能带来的后果,为良性的生态系统服务提供理论依据。基于1971-2000年锡林浩特市和阿巴嘎旗两个气象台站的平均温度和锡林郭勒盟境内16个气象站点的降水资料,结合地理信息系统技术,系统分析了气候变暖对典型草原区降水时空分布格局的影响。初步研究结果表明:气温变化过程和全球变暖的趋势相一致,特别是20世纪90年代气温上升变暖趋势最为强烈。在全球气候变暖的背景下,研究区的降雨量受东南季风的影响呈现由东南向西北递减的分布规律。但区域降雨存在明显的年代际变化特征,各区域降水变化差异显著,从东南到西北变化的幅度减小。30年来研究区的降雨量变化表现出时间、空间上的不规则性,表明全球气候变化对草原区过去30年的降雨影响不显著,没有达到可识别的程度。     

锡林郭勒盟不同生态地理区气候变化特点分析

文中利用1960-2007年锡林郭勒盟及其周边地区17个气象站的降水、气温数据,利用统计学的原理及方法,对比分析了锡林郭勒盟四个生态地理区气候变化的规律及区域差异,阐明全球气候变化在锡林郭勒盟不同区域的具体表现。研究结果对于认识草原区气候变化特点与加强草原生态环境保护等方面都具有极其重要的理论与实践价值。     

1960-2009年大连市气候暖干化研究

利用大连市1960-2009年气温和降水两个主要气象要素值的基本观测资料,运用线性倾向估计和GIS空间分析方法,探讨了大连气候的年际时空变化,同时利用Mann-Kendall统计检验和Morlet小波分析对其气候的年代际和周期性变化进行了分析。结果表明:近50a来大连市气候暖干化日趋明显,年平均气温以0.28℃/10a的速率显著上升,并且在1991年发生突变进入异常增暖期,空间上增暖趋势大致呈由南向东北逐渐减弱的态势;降水量基本经历了"减少-增加-减少-增加"的变化过程,总体上呈下降趋势,在1972年降水量由偏多向偏少转变,东北和西南地区降幅较大,腹地最小。此外,气候的暖干化趋势对"自然-社会-经济"复合系统造成的影响应引起重视。     

土壤呼吸对不同来源水分响应的研究进展

土壤是陆地生态系统最大的碳源,也是最大的碳汇。土壤呼吸作为全球碳循环的一个重要组成部分,是调控全球碳循环和气候变化的关键过程,也是当前全球变化生态学研究的重要领域和碳循环中碳收支研究中的一个热点问题。水分是土壤呼吸的重要扰动因子,比较不同来源土壤水分对土壤呼吸的影响,对准确估算土壤呼吸具有重要意义,这在干旱和半干旱地区尤为明显。通过土壤水分的3种主要来源：降水、灌溉和地下水,比较分析了土壤呼吸对不同来源水分的响应过程和规律,为今后土壤呼吸方面的研究提供参考。     

The relationship between energy consumption and economic growth and the development strategy of a low-carbon economy in Kazakhstan

Fossil energy is the material basis of human survival, economic development and social progress. The relationship between energy consumption and economic growth is becoming increasingly close. However, energy consumption is the major source of greenhouse gases, which can significantly affect the balance of the global ecosystem. It has become the common goal of countries worldwide to address climate change, reduce carbon dioxide emissions, and implement sustainable development strategies. In this study, we applied an approximate relationship analysis, a decoupling relationship analysis, and a trend analysis to explore the relationship between energy consumption and economic growth using data from Kazakhstan for the period of 1993–2010. The results demonstrated:(1) the total energy consumption and GDP in Kazakhstan showed a "U"-type curve from 1993 to 2010. This curve was observed because 1993–1999 was a period during which Kazakhstan transitioned from a republic to an independent country and experienced a difficult transition from a planned to a market economy. Then, the economic system became more stable and the industrial production increased rapidly because of the effective financial, monetary and industrial policy support from 2000 to 2010.(2) The relationships between energy consumption and carbon emissions, economic growth and energy exports were linked; the carbon emissions were mainly derived from energy consumption, and the dependence of economic growth on energy exports gradually increased from 1993 to 2010. Before 2000, the relationship between energy consumption and economic growth was in a recessional decoupling state because of the economic recession. After 2000, this relationship was in strong and weak decoupling states because the international crude oil prices rose and energy exports increased greatly year by year.(3) It is forecasted that Kazakhstan cannot achieve its goal of energy consumption by 2020. Therefore, a low-carbon economy is the best strategic choice to address climate change from a global perspective in Kazakhstan. Thus, we proposed strategies including the improvement of the energy consumption structure, the development of new energy and renewable energy, the use of cleaner production technologies, the adjustment and optimization of the industrial structure, and the expansion of forest areas.     

Spatial dynamics of aboveground carbon stock in urban green space:a case study of Xi’an,China

Greenhouse gas emission of carbon dioxide(CO2) is one of the major factors causing global climate change.Urban green space plays a key role in regulating the global carbon cycle and reducing atmospheric CO2.Quantifying the carbon stock,distribution and change of urban green space is vital to understanding the role of urban green space in the urban environment.Remote sensing is a valuable and effective tool for monitoring and estimating aboveground carbon(AGC) stock in large areas.In the present study,different remotely-sensed vegetation indices(VIs) were used to develop a regression equation between VI and AGC stock of urban green space,and the best fit model was then used to estimate the AGC stock of urban green space within the beltways of Xi’an city for the years 2004 and 2010.A map of changes in the spatial distribution patterns of AGC stock was plotted and the possible causes of these changes were analyzed.Results showed that Normalized Difference Vegetation Index(NDVI) correlated moderately well with AGC stock in urban green space.The Difference Vegetation Index(DVI),Ratio Vegetation Index(RVI),Soil Adjusted Vegetation Index(SAVI),Modified Soil Adjusted Vegetation Index(MSAVI) and Renormalized Difference Vegetative Index(RDVI) were lower correlation coefficients than NDVI.The AGC stock in the urban green space of Xi’an in 2004 and 2010 was 73,843 and 126,621 t,respectively,with an average annual growth of 8,796 t and an average annual growth rate of 11.9%.The carbon densities in 2004 and 2010 were 1.62 and 2.77 t/hm2,respectively.Precipitation was not an important factor to influence the changes of AGC stock in the urban green space of Xi’an.Policy orientation,major ecological greening projects such as "transplanting big trees into the city" and the World Horticultural Exposition were found to have an important impact on changes in the spatiotemporal patterns of AGC stock.     

拉萨城市大气污染现状及防治对策

青藏高原是全球气候变化的晴雨表,拉萨作为这片高原上的重要城市之一,它的大气污染无疑将成为青藏高原的直接污染源,因此对拉萨城市大气污染状况的关注和研究,显得尤为重要。本文较全面地总结了拉萨城市大气污染现状,系统分析了大气污染形成原因,并结合拉萨的实际探讨几点防治措施以供参考。     

Assessing ecological vulnerability in western China based on Time-Integrated NDVI data

Arid and semi-arid areas are the most vulnerable regions to climate change.Clear understanding of the effects of climate change on ecosystems in arid and semi-arid regions and the ecosystem vulnerability is important for ecosystem management under the background of climate change.In this study,we conducted a vulnerability assessment on various ecosystems from 1982 to 2013 in western China with large areas of arid and semi-arid lands based on the Time-Integrated Normalized Difference Vegetation Index(TINDVI)data and climate data.The results indicated that grasslands were the most vulnerable ecosystem to climate change in western China,especially for those in Tibetan Plateau.Croplands in oases were not vulnerable to climate change compared to rain-fed croplands in semi-arid regions(e.g.Gansu and Inner Mongolia),which was attributed to the well-developed drip irrigation technology in oases.Desert and Gobi ecosystems were slightly vulnerable to climate change during the past several decades.The assessment results,as revealed in this study,can provide a reference for taking appropriate actions to protect the ecosystems in western China.     

Investigating natural drivers of vegetation coverage variation using MODIS imagery in Qinghai,China

The climatically sensitive Qinghai province of China has been recognized as a hotspot for studies on the feedbacks of terrestrial ecosystems to global climate change. Thus, investigating vegetation coverage and its natural drivers in Qinghai is an important focus of ecosystem research. On the basis of Moderate Resolution Imaging Spectroradiometer(MODIS) Enhanced Vegetation Index(EVI) time series data, we estimated the vegetation coverage in this region using the dimidiate pixel model. Trend analyses, correlations between meteorological parameters, changes in vegetation coverage, and the temporal and spatial relationships between soil texture and vegetation coverage were used to investigate the possible drivers of vegetation coverage variations. The results indicated that the reduction of vegetation coverage slowed down in the period from 2000 to 2012. Annual mean temperature was the main climatic driver of the total extremely low and low vegetation coverage areas in Qinghai, followed by the precipitation anomalies. The extremely low and low vegetation coverage areas were mainly distributed in regions with a mean annual relative air humidity of <40% and the spatial distributions of these two area types differentiated along the 200-mm rainfall contours. The total extremely low and low vegetation coverage areas were mainly characterized by sandy clay loam soil, followed by loamy sand and sandy soil. Regions with sandy loam or loam soil have the greatest risk of vegetation coverage reductions. Knowledge of vegetation coverage variation and its natural drivers in the ecologically fragile region of Qinghai can provide scientific support for managing environmental change and desertification.     

气候变化和人类活动对蒙古高原植被覆盖变化的影响

基于全球监测与模型研究组（GIMMS）归一化植被指数(NDVI),对蒙古高原地区1981-2006年植被覆盖的时空变化进行了研究,并从气候变化和人类活动的角度,分析了植被覆盖变化的原因。1981-2006年蒙古高原的植被覆盖时空分布具有明显的地带性特征,森林区及荒漠区植被覆盖呈现小幅下降趋势,草原区呈现上升趋势,蒙古高原NDVI分布从东北向西南、从高原南北边缘地带向中心地带呈明显的规律性变化：高原东北部的大兴安岭地区NDVI最高,蒙古国北部的杭爱山脉次之,西南部荒漠区的NDVI最低。研究表明: 植被覆盖变化是气候变化和人类活动共同作用的结果,蒙古高原地区的降水变化是植被覆盖变化的重要原因,森林砍伐、河套耕作及城镇化等人类活动则是导致具有相似气候条件的内蒙古与蒙古国植被覆盖变化区域差异的原因。     

Estimation of net primary productivity and its driving factors in the Ili River Valley,China

Net primary productivity(NPP), as an important variable and ecological indicator in grassland ecosystems, can reflect environmental change and the carbon budget level. The Ili River Valley is a wetland nestled in the hinterland of the Eurasian continent, which responds sensitively to the global climate change. Understanding carbon budget and their responses to climate change in the ecosystem of Ili River Valley has a significant effect on the adaptability of future climate change and sustainable development. In this study, we calculated the NPP and analyzed its spatio-temporal pattern of the Ili River Valley during the period 2000–2014 using the normalized difference vegetation index(NDVI) and an improved Carnegie-Ames-Stanford(CASA) model. Results indicate that validation showed a good performance of CASA over the study region, with an overall coefficient of determination(R2) of 0.65 and root mean square error(RMSE) of 20.86 g C/(m~2·a). Temporally, annual NPP of the Ili River Valley was 599.19 g C/(m~2·a) and showed a decreasing trend from 2000 to 2014, with an annual decrease rate of –3.51 g C/(m~2·a). However, the spatial variation was not consistent, in which 55.69% of the areas showed a decreasing tendency, 12.60% of the areas remained relatively stable and 31.71% appeared an increasing tendency. In addition, the decreasing trends in NPP were not continuous throughout the 15-year period, which was likely being caused by a shift in climate conditions. Precipitation was found to be the dominant climatic factor that controlled the inter-annual variability in NPP. Furthermore, the correlations between NPP and climate factors differed along the vertical zonal. In the medium-high altitudes of the Ili River Valley, the NPP was positively correlated to precipitation and negatively correlated to temperature and net radiation. In the low-altitude valley and high-altitude mountain areas, the NPP showed a negative correlation with precipitation and a weakly positive correlation with temperature and net radiation. The results suggested that the vegetation of the Ili River Valley degraded in recent years, and there was a more complex mechanism of local hydrothermal redistribution that controlled the growth of vegetation in this valley ecosystem.     

陕甘宁接壤区气候变化特征及其生态环境效应

为了能够正确反映陕甘宁接壤区多年气候变化的趋势,特别是1999年以后的气候改善状况,利用线性回归分析、趋势分析等方法对1951～2004年间39个测站的气温和降水的记录进行分析.结果表明:陕甘宁接壤区暖干化趋势明显,多年来一直处于干燥的状态,气温在波动中不断升高,降水在波动中不断减少,这种恶劣的气候状况严重影响了陕甘宁接壤区的生态环境建设.但是1999年之后,在气候暖干化的大背景之下,气温有所降低,降水有所增加,这是一个较好的气候变化趋势,对于气候的转型以及生态环境的重建有着重要的意义.     

中欧山松大小蠹在中国的适生性分析

中欧山松大小蠹(Dendroctonus ponderosae Hopkins)是严重危害松类针叶树种的蛀干害虫。本文基于气象数据,利用BIOCLIM生态位模型对中欧山松大小蠹在我国的适生区进行了分析,结果显示该小蠹能广泛分布在华北、东北的大部分地区和西南的部分地区,提供了ArcGIS适生区预测分布图。     

中国西北干旱区1981～2001年NDVI对气候变化的响应分析

气候变化在不同的区域有着不同的特征,对植被也带来不同的影响,对不同地区气候变化特征的认识及植被变化的相应分析,可使我们对全球变化对干旱区的影响有更深入的认识。本文通过定量分析西北干旱区1981~2001年NOAA/AVHRR数据和同期的气象资料,借助于遥感技术和数理统计知识,分析了1981~2001年我国西北干旱区NDVI变化及其与气候变化的关系。结果显示:1981-2001年间西北干旱区年际最大NDVI的变化与气候变化具有明显的相关性,尤其是对新疆的南、北疆来说,NDVI的变化受到年降水量、年均温和空气相对湿度的影响比较显著,NDVI与年降水量和相对湿度的相关程度要明显比与年均温的相关程度高。甘肃内蒙古的河西走廊和青海的柴达木地区NDVI没有明显的变化趋势,同时这两个地区也是年降水量变化最小的地区。从而得出一个结论:降水资源是我国西北干旱区植被生长和生态建设的最重要气象因子,只有充分、合理地利用"降水"这种天然水资源才能最终实现中国西北干旱区环境、社会与经济的可持续发展。