Modelling the trade-off between fire and grazing in a tropical savanna landscape, northern Australia.

As savannas are widespread across northern Australia and provide northern rangelands, the sustainable use of this landscape is crucial. Both fire and grazing are known to influence the tree-grass character of tropical savannas. Frequent fires open up the tree layer and change the ground layer from perennials to that dominated by annuals. Annual species in turn produce copious quantities of highly flammable fuel that perpetuates frequent, hot fires. Grazing reduces fuel loads because livestock consumes fuel-forage. This trade-off between fire and grazing was modelled using a spatially explicit, process-orientated model (SAVANNA) and field data from fire experiments performed in the Victoria River District of northern Australia. Results of simulating fire (over 40 years) with minimal or no grazing pressure revealed a reduction in the shrub and woody plants, a reduction in grasses, and no influence on the tree structure given mild fires. While mature trees were resistant to fire, immature trees, which are more likely associated with the shrub layer, were removed by fire. The overall tree density may be reduced with continual burning over longer time periods because of increasing susceptibility of old trees to fire and the lack of recruitment. Increases in stocking rates created additional forage demands until the majority of the fuel load was consumed, thus effectively suppressing fire and reverting to the grazing and suppressed fire scenario where trees and shrubs established.     

Building blocks of economic resilience to climate change: a south east Australian fisheries example

Climate change will impact on ecological, social, and economic elements of fisheries; however, the three are seldom considered in an integrated fashion. We develop a fishery-level assessment of economic resilience to climate change for the Tasmanian rock lobster fishery, a linked social–ecological system. We outline the main climate change forcing influences that link climate change to the fishery via changes in lobster abundance, distribution, and phenology. Using a bottom-up approach, we identify twelve economic attributes strongly related to the fisheries’ economic resilience to climate change. Resilience attributes are grouped according to the level of the economic domain (business, sectoral, and governance). Attributes are then evaluated to determine the overall economic resilience of the rock lobster fishery in the context of the specific nature of predicted climate change effects. We identify areas of low resilience in the economic sub-system for this fishery. Evaluating the economic resilience of regional fisheries using this integrated, interdisciplinary framework provides a practical, parsimonious, and conceptually sound basis for undertaking comprehensive and contextually tailored assessments of climate change impacts and economic vulnerability. The framework can be extended to include a broader range of climate change impacts and the social domain of the human sub-system.     

Climate change vulnerability and resilience: current status and trends for Mexico

Climate change alters different localities on the planet in different ways. The impact on each region depends mainly on the degree of vulnerability that natural ecosystems and human-made infrastructure have to changes in climate and extreme meteorological events, as well as on the coping and adaptation capacity toward new environmental conditions. This study assesses the current resilience of Mexico and Mexican states to such changes, as well as how this resilience will look in the future. In recent studies (Moss et al. in Vulnerability to climate change: a quantitative approach. Pacific Northwest National Laboratory, Washington DC, 2001; Brenkert and Malone in Clim Change 72:57–102, 2005; Malone and Brenkert in Clim Change 91:451–476, 2008), the Vulnerability–Resilience Indicators Model (VRIM) is used to integrate a set of proxy variables that determine the resilience of a region to climate change. Resilience, or the ability of a region to respond to climate variations and natural events that result from climate change, is given by its adaptation and coping capacity and its sensitivity. On the one hand, the sensitivity of a region to climate change is assessed, emphasizing its infrastructure, food security, water resources, and the health of the population and regional ecosystems. On the other hand, coping and adaptation capacity is based on the availability of human resources, economic capacity, and environmental capacity. This paper presents two sets of results. First, we show the application of the VRIM to determine state-level resilience for Mexico, building the baseline that reflects the current status. The second part of the paper makes projections of resilience under socioeconomic and climate change and examines the varying sources and consequences of those changes. We used three tools to examine Mexico’s resilience in the face of climate change, i.e., the baseline calculations regarding resilience indices made by the VRIM, the projected short-term rates of socioeconomic change from the Boyd–Ibarrarán computable general equilibrium model, and rates of the IPCC-SRES scenario projections from the integrated assessment MiniCAM model. This allows us to have available change rates for VRIM variables through the end of the twenty-first century.     

Regional integration and local change: road paving, community connectivity, and social–ecological resilience in a tri-national frontier, southwestern Amazonia

Initiatives for global economic integration increasingly prioritize new infrastructure in relatively remote regions. Such regions have relatively intact ecosystems and provide valuable ecosystem services, which has stimulated debates over the wisdom of new infrastructure. Most prior research on infrastructure impacts highlights economic benefits, ecological damage, or social conflicts. We suggest a more integrative approach to regional integration by appropriating the concepts of connectivity from transport geography and social?Cecological resilience from systems ecology. Connectivity offers a means of observing the degree of integration between locations, and social?Cecological resilience provides a framework to simultaneously consider multiple consequences of regional integration. Together, they offer a spatial analysis of resilience that considers multiple dimensions of infrastructure impacts. Our study case is the southwestern Amazon, a highly biodiverse region which is experiencing integration via paving of the Inter-Oceanic Highway. Specifically, we focus on the ??MAP?? region, a tri-national frontier where Bolivia, Brazil, and Peru meet and which differs in the extent of highway paving. We draw on a tri-national survey of more than 100 resource-dependent rural communities across the MAP frontier and employ indicators for multiple dimensions of connectivity and social?Cecological resilience. We pursue a comparative analysis among regions and subregions with differing degrees of community connectivity to markets in order to evaluate their social?Cecological resilience. The findings indicate that connectivity and resilience have a multifaceted relationship, such that greater community connectivity corresponds to greater resilience in some respects but not others. We conclude by noting how our findings integrate those from heretofore largely disparate literatures on infrastructure. The integration of transport geography with resilience thought thus stands to advance the study of infrastructure impacts.     

Land-use and land-cover effects on regional biodiversity distribution in a subtropical dry forest: a hierarchical integrative multi-taxa study

Latin American subtropical dry ecosystems have experienced significant human impact for more than a century, mainly in the form of extensive livestock grazing, forest products extraction, and agriculture expansion. We assessed the regional-scale effect of land use and land cover (LULC) on patterns of richness distribution of trees, birds, amphibians, and mammals in the Northern Argentine Dry Chaco (NADC) over c. 19 million hectares. Using species distribution models in a hierarchical framework, we modeled the distributions of 138 species. First, we trained the models for the entire Argentinean Chaco with climatic and topographic variables. Second, we modeled the same species for the NADC including the biophysical variables identified as relevant in the first step plus four LULC-related variables: woody biomass, distance to crops, density of livestock-based rural settlements (puestos), and vegetation cover. Third, we constructed species richness maps by adding the models of individual species and considering two situations, with and without LULC variables. Four, richness maps were used for assessing differences when LULC variables are added and for determining the main drivers of current patterns of species richness. We found a marked decrease in species richness of the four groups as a consequence of inclusion of LULC variables in distribution models. The main factors associated with current richness distribution patterns (both negatively) were woody biomass and density of livestock puestos. Species richness in present-day Semiarid Chaco landscapes is strongly affected by LULC patterns, even in areas not transformed to agriculture. Regional-scale biodiversity planning should consider open habitats such as grasslands and savannas in addition to woodlands.     

Discovering and characterizing farm households’ resilience under water scarcity

Water scarcity at an alarming rate has been a limiting factor for sustainable agriculture in arid and semi-arid environments of the world. It has resulted in a number of problems such as poverty and food insecurity among farm households. Therefore, building and improving resilience, as a way to mitigate the impacts of water scarcity, is important for farm households. But one of the significant steps for planning to improve farm households’ resilience under water scarcity is investigation of the current level of resilience of these households and understanding their variances. Therefore, this study offers a classification of farm households’ diversity based on resilience. Primary data were collected from 260 randomly selected farm households in 21 villages around Parishan wetland, Iran. Farm Household Resilience Scale was used to measure resilience. Cluster analysis suggested three groups: highly, medium-, and low-resilient farm households. The results of comparing three groups revealed that highly resilient farm households characterize with higher risk management, more agricultural water security, more positive psychological traits, and better knowledge management. Also, they had better water quality, attended more agricultural extension activities, and used modern irrigation systems. Farm households’ resilience map using GIS software illustrated that there is a relationship between resilience and farm location from the wetland. The findings of this study could be used by planner and policy-makers to improve farm households’ resilience in arid and semi-arid environments. Improvement in knowledge management system is recommended as one of the most effective policy instruments in building resilience.     

Evaluating land cover change and its impact on hydrological regime in Upper Shire river catchment, Malawi

A study was conducted to investigate hydrological impacts of land cover changes in the degradation of the hydrological on flow regimes of the Upper Shire river, Malawi. Remote sensing techniques were used to inventory temporal changes of land cover changes in the catchment. Hydrological data were analyzed to reveal the alterations and trends for two periods; 1989 and 2002. The study revealed significant changes in magnitude and direction that have occurred in the catchment between 1989 and 2002, mainly in areas of human habitation. Trends in land cover change in the Upper Shire river catchment depict land cover transition from woodlands to mostly cultivated/grazing and built-up areas. The land cover mapping showed that 23% of the land was covered by agricultural land in 1989. Subsistence agricultural area has increased by 18%, occupying 41% of the study area in 2002. The effects of the derived land cover changes on river flow in the Upper Shire river were investigated using the semi distributed soil and water assessment tool (SWAT) model. River flows were found to be highly variable and sensitive to land cover changes. Simulation results show that 2002 land cover data produces higher flow peaks and faster travel times compared to the 1989 land cover data. The changes detected indicate the effects of land use pressure in the catchment. The study highlights the importance of considering effects of land use and land cover changes on ecosystems, and water resources for an informed decision on proper catchment planning and management.     

Potential responses of terrestrial biodiversity in Southern Africa to anthropogenic climate change

Key studies supported by species-level data collection have provided early indications of the potential implications of unmitigated change for the ecosystems and biodiversity of southern Africa. These suggest a significant threat to biodiversity, both from changing bioclimatic suitability and changing atmospheric CO₂ level that seems to affect the competitive balance between woody and herbaceous plants in the dominant savanna biome of this region. Modeling efforts suggest significant implications of unmitigated climate change for this region, but assumptions underpinning methods such as bioclimatic modeling must be recognized, some of which might lead to over estimates of the rate and extent of the potential impacts. General trends and level of coincidence between various types of studies do support a high degree of concern for a substantial portion of southern African biodiversity under unmitigated climate-change scenarios. The most significant changes in ecosystem structure (both increases and decreases in woody plant cover), and associated faunal diversity changes, are projected in the dominant savanna vegetation type in this region, while the most significant biodiversity loss is projected for the winter rainfall region. Follow-up work to detect early signs of climate change identify regions of high- and low-potential impacts, and experimental work to test some important hypotheses relating to the future evolution of climate-change impacts across the region are very few and urgently required.     

Climate change and Australia: key vulnerable regions

Natural ecosystems are generally considered to be one of the most vulnerable sectors to negative impacts from rapid climate change. Australia’s rich biodiversity is already under considerable threat from multiple human impacts, and climate change will impose additional stress. Opportunities for most Australian species to adapt to climate change by altering their distribution will be limited due to a number of characteristics of the Australian environment, both physical and biotic, including topography, habitat fragmentation, low capacity for dispersal and the restricted geographic ranges of many species. This review summarizes recent and projected climate trends in Australia and discusses how species may respond to these changes in the context of the particular environmental characteristics and biogeographic history of the continent. It also identifies particular regions and ecosystems likely to be most negatively affected in the short to medium term.     

Landscape changes and environmental quality: the evolution of land vulnerability and potential resilience to degradation in Italy

Resilience, considered as the ability of a system to absorb and compensate pressures derived from human and natural systems, is a topic of interest in the Mediterranean region whose landscape is the joint result of social, economic and environmental factors. The present study analyses the changes in the Italian landscape over two periods (1960–1990 and 1990–2010) of the last 50 years through a composite index of environmental resilience and vulnerability to land degradation. Results indicate that the spatial distribution of this index has been considerably changed from a relatively simple geography (mainly reflecting a latitude gradient) to a more complex pattern. The level of vulnerability of southern Italian land maintained quite stable while increasing significantly in Northern and Central Italy. The (potential) resilience level decreased over time in Central and Northern Italy while growing moderately in Southern Italy. This means that important processes of environmental changes impacting landscape resilience occurred with a different spatial trend in Italy. The composite index derived from vulnerability and potential resilience estimates at the regional scale revealed crucial to map over time the increase of surface land exposed to desertification risk. Results support the adoption of measures promoting a sustainable land management in environmentally vulnerable land with low potential to resilience.     

Planned retreat as a management response to coastal risk: a case study from the Fleurieu Peninsula, South Australia

Australian coastal areas have been identified as highly vulnerable to climate change, with major projected impacts including sea level rise, extreme weather events, increased erosion, and a change in coastal processes and wave patterns. Such impacts would cause coastal settlements and ecosystems to face increasingly uncertain conditions. In response to increased risk, effective coastal management at local and regional scales is needed, with governing bodies providing significant leadership. This research explores the challenges of applying effective adaptation responses to projected climate change in vulnerable coastal systems on the South Coast of the Fleurieu Peninsula, South Australia. In particular, the option of planned retreat as a management response to coastal risk is critically examined, with the incorporation of learning from Byron Bay, NSW. A mixed methods approach was undertaken by integrating documentary interrogation with the analysis of interview responses from key coastal managers. It was determined that despite the increase in adaptation planning and development of management strategy options to manage sea level rise on the Fleurieu Peninsula, there is a lack of implementation of adaptation responses. In addition, planning seems to focus largely on the implications of sea level rise on infrastructure, often overlooking other risks and possible ecological impacts. Inconsistencies in governance are reflected at all levels, indicating a need for comprehensive improvements to ensure the incorporation of appropriate risk responses into planning decisions.     

基于社会生态系统视角的长三角地级城市韧性度评价

为提升城市应对重大冲击和慢性压力的能力,提高城市的抗打击能力与恢复能力,以及城市对抗不确定风险的韧性程度,本文结合现实背景,以城市社会生态系统的视角,对2014年长三角地区16个地级城市韧性进行实证分析。采用GIS的空间分析和叠加功能方法,从生态环境、市政设施、经济和社会发展4个方面选取24个具体指标,对长三角地区16个地级城市韧性程度及其空间状态做出评价,并确定测度标准值。首先对构成城市韧性的4个因子:生态、市政设施工程、经济以及社会发展进行分析和数字化,得出各因子对城市韧性影响程度的栅格图层;其次对图层进行空间叠加,再得到长三角地区地级城市韧性度评价图。评价结果表明:(1)长三角地级城市韧性呈现"级差化"分布状态,总体呈现出中等韧性状态;(2)长三角地级城市韧性空间分异特征显著,其北翼城市比南翼城市韧性程度较高;(3)长三角地级城市经济、生态韧性在空间分布上相对集中,趋向协调均衡发展。通过城市韧性度分析,认为评价结果基本符合近年来长三角地区城市韧性发展的整体状况,可以在一定程度上增强城市社会生态系统对外界风险的适应能力,并在今后的城市发展调适过程中更具韧性,从而对不同时空尺度的城市韧性状态评价提供一种思路。     

Livelihoods and landscapes at the threshold of change: disaster and resilience in a Chiapas coffee community

In 2005, torrential rains associated with Hurricane Stan devastated farm systems in southern Mexico. We present a case study on the impacts of and responses to Hurricane Stan by coffee households in three communities in the highlands of Chiapas, Mexico, with the objective of illuminating the linkages between household vulnerability and resilience. We analyze data from 64 household surveys in a cluster analysis to link household impacts experienced to post-Stan adaptive responses and relate these results with landscape-level land-cover changes. The degree of livelihood change was most significant for land-constrained households whose specialization in coffee led to high exposure and sensitivity to Stan and little adaptive capacity. Across the sample, the role of coffee in livelihood strategies declined, as households sought land to secure subsistence needs and diversified economically after Stan. Nevertheless, livelihoods and landscape outcomes were not closely coupled, at least at the temporal and spatial scale of our analysis: We found no evidence of land-use change associated with farmers’ coping strategies. While households held strong attitudes regarding effective resource management for risk reduction, this knowledge does not necessarily translate into capacities to manage resilience at broader scales. We argue that policy interventions are needed to help materialize local strategies and knowledge on risk management, not only to allow individual survival but also to enhance resilience at local, community and landscape scales.     

Land-use legacies in the forest structure of silvopastoral oak woodlands in the Eastern Mediterranean

Eastern Mediterranean silvopastoral oak woodlands have been greatly damaged through forest conversion, illegal lumbering, overgrazing, and forest fires. The aim of this study was to assess land-use changes and the legacies that they have imprinted on the forest structure of Quercus macrolepis and accompanying Quercus pubescens and Quercus cerris woodlands on Lesvos Island, Greece. The size structures of adult oak populations were analyzed as indicators of long-term oak regeneration, while short-term recruitment was determined by counting oak seedlings and saplings. The size structure of the adult Q. macrolepis population was similar to the inverse J-shaped distribution typical for natural Mediterranean oak forests, indicating continuous recruitment with a constant mortality rate of mature individuals. Seedling and sapling densities were highly variable, but generally low in relation to adult oak densities. Recruitment of oak seedlings and saplings was positively related to determinants such as forest cover, adult oak density and basal area, woody plant richness, and litter cover. Both seedling and sapling occurrence were negatively associated with dung frequency, which suggests that sheep grazing imposes a barrier to oak recruitment. The study outlines a comprehensive land-use transition from the 1950 to 1970s, during which a complex and multifunctional agrosilvopastoral land-use system was simplified to an intensive grazing system. The discrepancy between the successful long-term regeneration and the less successful short-term recruitment of oaks illustrates that intensified livestock grazing has been a major driver of vegetation change. Grazing impact is likely to interact with increasing drought conditions, which may trigger a negative feedback cycle that undermines the capacity of woodlands to sustain ecosystem services.     

Dwelling in the biosphere: exploring an embodied human–environment connection in resilience thinking

Resilience has emerged as a prominent paradigm for interpreting and shaping human–environment connections in the context of global environmental change. Resilience emphasizes dynamic spatial and temporal change in social–ecological systems where humans are inextricably interwoven with the environment. While influential, resilience thinking has been critiqued for an under-theorized framing of socio-cultural dynamics. In this paper, we examine how the resilience concepts of planetary boundaries and reconnecting to the biosphere frame human–environment connection in terms of mental representations and biophysical realities. We argue that focusing solely on mental reconnection limits further integration between the social and the ecological, thus countering a foundational commitment in resilience thinking to social–ecological interconnectedness. To address this susceptibility we use Tim Ingold’s ‘dwelling perspective’ to outline an embodied form of human–environment (re)connection. Through dwelling, connections are not solely produced in the mind, but through the ongoing interactivity of mind, body and environment through time. Using this perspective, we position the biosphere as an assemblage that is constantly in the making through the active cohabitation of humans and nonhumans. To illustrate insights that may emerge from this perspective we bring an embodied connection to earth stewardship, given its growing popularity for forging local to global sustainability transformations.     

Geo-based model of intrinsic resilience to climate change: an approach to nature-based solution

A substantial amount of researches have been done on the understanding and assessment of resilience from multiple perspectives, e.g., ecological, social, economic, and disaster management; however, recent international approach is trending toward more systematic and comprehensive risk assessment processes. Pivotal element of such approach is to emphasizing on promoting resilience in the face of climate change impacts. Conceptualization and identification of parameters to assess climate change resilience is one of the remaining challenges that academia is facing. Reviewing the principles of the climate change resilience highlighted in the literature, the goal of this study is to introduce a theoretical model about the climate change resilience concept to facilitate and enhance future climate change resilience-related researches. The model proposed in this study is named as the climate change resilience of place (C-CROP) model, a geo-based model which is designed to assess climate change resilience for any geographic region with an approach to the incorporation of nature-based solution (NBS). C-CROP model considers vulnerability, exposure, sensitivity to climate change on one side; another side is co-benefit, climate proofing, and disservices of proposed NBS. An operational framework of the C-CROP model is also proposed, that allows spatially explicit assessment of climate change resilience in real world by developing an indicator-based framework and comprehensive mapping using the geospatial approach. Therefore, this model includes vulnerability hotspots identification; better understanding of the pathways of resilience; and solutions (i.e., NBS) to infer the impacts and effectiveness of resilience-building interventions.

     

Regional patterns and controls of biomass in semiarid woodlands: lessons from the Northern Argentina Dry Chaco

Land use change, particularly in forested ecosystems, has a direct impact on the global carbon cycle. Consequently, the regional assessment of biomass and the understanding of its current spatial controls are research priorities for regional ecology and land use. Field data and satellite imagery were combined here to map woodlands and estimate their above-ground biomass (AGB) in the Dry Chaco ecoregion of northern Argentina. Allometric equations were used to derive AGB from diameter at breast height data collected at 50 samples during 2007. In order to generate the AGB regional map, this information was later associated with MODIS-Terra spectral data (NDVI) using the Random Forest (RF) method. Finally, AGB spatial patterns were associated with potential biophysical and human controlling factors through correlation and regression analyses. Results indicate that the use of RF and NDVI of the dry season derived from MODIS-Terra was suitable to map regional AGB, what makes this methodology applicable to other dry woodlands. The RF model used to map AGB showed a mean deviation of 2.9 % and a precision of 15 % for one prediction. At this regional scale of analysis, biophysical rather than human factors controlled AGB spatial patterns, in part because the region includes a wide range of environmental situations. Warmer conditions showed a higher biomass, suggesting an energetic limitation for AGB accumulation. However, human controls (distance to towns, cultivation, and roads) also conditioned AGB patterns, suggesting lower AGB values near cultivated areas. The relation between AGB and water availability was surprisingly weak, but partially obscured by the land use history and degradation due to extensive cattle ranching. We propose that a combination of environmental factor and land use affects the AGB regional patterns and promotes unexpected relationships with environmental factors. This work represents the first spatially explicit AGB (patterns and controls) analysis for an extensive subtropical dry woodland area (113,000 km²) and shows how biophysical and human factors co-control regional patterns.     

Climate change adaptation and mitigation in smallholder crop–livestock systems in sub-Saharan Africa: a call for integrated impact assessments

African mixed crop–livestock systems are vulnerable to climate change and need to adapt in order to improve productivity and sustain people’s livelihoods. These smallholder systems are characterized by high greenhouse gas emission rates, but could play a role in their mitigation. Although the impact of climate change is projected to be large, many uncertainties persist, in particular with respect to impacts on livestock and grazing components, whole-farm dynamics and heterogeneous farm populations. We summarize the current understanding on impacts and vulnerability and highlight key knowledge gaps for the separate system components and the mixed farming systems as a whole. Numerous adaptation and mitigation options exist for crop–livestock systems. We provide an overview by distinguishing risk management, diversification and sustainable intensification strategies, and by focusing on the contribution to the three pillars of climate-smart agriculture. Despite the potential solutions, smallholders face major constraints at various scales, including small farm sizes, the lack of response to the proposed measures and the multi-functionality of the livestock herd. Major institutional barriers include poor access to markets and relevant knowledge, land tenure insecurity and the common property status of most grazing resources. These limit the adoption potential and hence the potential impact on resilience and mitigation. In order to effectively inform decision-making, we therefore call for integrated, system-oriented impact assessments and a realistic consideration of the adoption constraints in smallholder systems. Building on agricultural system model development, integrated impact assessments and scenario analyses can inform the co-design and implementation of adaptation and mitigation strategies.F     

Impacts of climate change on Chinese ecosystems: key vulnerable regions and potential thresholds

China is a key vulnerable region of climate change in the world. Climate warming and general increase in precipitation with strong temporal and spatial variations have happened in China during the past century. Such changes in climate associated with the human disturbances have influenced natural ecosystems of China, leading to the advanced plant phenology in spring, lengthened growing season of vegetation, modified composition and geographical pattern of vegetation, especially in ecotone and tree-lines, and the increases in vegetation cover, vegetation activity and net primary productivity. Increases in temperature, changes in precipitation regime and CO₂ concentration enrichment will happen in the future in China according to climate model simulations. The projected climate scenarios (associated with land use changes again) will significantly influence Chinese ecosystems, resulting in a northward shift of all forests, disappearance of boreal forest from northeastern China, new tropical forests and woodlands move into the tropics, an eastward shift of grasslands (expansion) and deserts (shrinkage), a reduction in alpine vegetation and an increase in net primary productivity of most vegetation types. Ecosystems in northern and western parts of China are more vulnerable to climate changes than those in eastern China, while ecosystems in the east are more vulnerable to land use changes other than climate changes. Such assessment could be helpful to address the ultimate objective of the United Nations Framework Convention on Climate Change (UNFCCC Article 2).     

干旱对生态系统脆弱性的影响研究——以长江中下游地区为例

将干旱作为定性事件,以长江中下游地区为研究对象,基于生态系统过程模型的动态模拟,根据IPCC有关脆弱性的概念,以生态系统功能特征量偏离多年平均状况的程度及其变化趋势分别定义生态系统对降水变化的敏感性和适应性,在生态系统的尺度上评估其对干旱的脆弱性。结果表明,长江中下游区域生态系统对降水脆弱性的空间分布有较为明显的区域差异。轻度脆弱及以下的生态系统占区域总面积的65%,主要分布在区域的中南部。重度脆弱和高度脆弱区域约占20%,主要分布在长江中下游的西北部。区域内生态系统对降水变率的平均脆弱度为轻度脆弱。干旱会显著增加研究区生态系统的脆弱性,具体表现为干旱导致原本不脆弱的生态系统脆弱度增加,而对脆弱度较高的生态系统的脆弱性影响不大。不同类型生态系统对干旱的响应稍有差异,干旱导致森林生态系统和农业生态系统的脆弱性均有所增加,但农业生态系统对干旱的脆弱性更高于森林生态系统。在研究区内,干旱对生态系统的影响会持续一段时间,但在干旱过后一年,不论是农业生态系统还是森林生态系统的脆弱性均有进一步上升,但相对多年平均水平没有显著差异