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71.
The structure and functioning of semi-arid ecosystems are strongly influenced by precipitation patterns. Water availability in such environments is highly pulsed, and discrete rainfall events interspersed with drought periods are important components of the annual water supply. Plant communities do not only respond to rainfall quantity, but also to variations in time, so that relatively small changes in rainfall frequency (i.e., pulsed inputs) may have strong effects on communities. Within the Mediterranean basin, climate change models forecast a decrease in mean annual precipitation and more extreme events (i.e., less rainy days and longer drought periods between events), along with seasonal changes. However, little is known on the consequences of these future precipitation changes on plant communities, especially in semi-arid environments. Here, we summarize the few experiments that have manipulated rainfall patterns in arid and semi-arid areas worldwide, and introduce the first results of a pioneer, long-term rainfall exclusion in the semi-arid southeast region of the Iberian Peninsula. The experiment is not only manipulating the amount of rainfall, but also its frequency and seasonal distribution in a grassland-shrubland in the Tabernas desert (Almería, Spain). This work monitored the effect of precipitation changes on different ecosystem processes for five years, at the species and community level, concluding that this plant community (as other communities studied in the same area) exhibited great resilience to changes in rainfall availability, likely caused by plant adaptation to large intra- and inter-annual precipitation variability.  相似文献   
72.
While a sustained flow of ecosystem services brings tangible benefits to humans, some ecosystem states and suites of services may be more desired by some people than others. Allocating or using the flow of services is loaded with asymmetries, complex power dynamics and political struggles between groups of people. We argue that the issues associated with such allocation and use questions are poorly integrated into the literatures of resilience, sustainability, and vulnerability. To illustrate this, we focus on three socially constructed factors that inhibit a fuller understanding about how to sustain the flow of ecosystem services: (1) rigidity/poverty traps; (2) power asymmetries; and (3) scientization of policy/politicization of science. These factors limit our ability to assess the sustainable flows of ecosystem services, and in particular to better understand the trade-offs and limits to aggregate human activity. We demonstrate that an improved understanding of the allocation trade-offs and limits to the flows of ecosystem services could result from more applied research that integrates the developing fields of deliberative democracy, pragmatic environmental philosophy, and legitimacy and rule compliance. Without the understanding that such integration would bring, researchers and policy makers risk underestimating the limits on flows of ecosystem services and how to accomplish their provision toward the greater collective - rather than individual - good.  相似文献   
73.
The paper considers the extent to which social–ecological systems research might contribute to an improved understanding of the social and environmental impacts of teleconnections inherent in economic globalisation. Recognising the importance and specificity of regional interconnections, wherein actions in certain parts of the world impact quite specifically on the sustainability of certain other spatially distant places and systems, the paper reflects on the social and environmental implications of increasingly interconnected agri-food systems and intersecting global commodity chains. Key elements of social–ecological systems approaches, which have purported relevance to research on globalisation, are critically examined, and aspects of social–ecological systems thinking that pose challenges for its application in this context are considered. Wider implications and limitations of social–ecological systems approaches to research and practice in (global) governance for sustainability are discussed. The general conclusion is that social–ecological systems research may offer insights into the governance of social and environmental impacts of agri-food systems and other complex systems at certain scales. However, the formal utility of concepts like resilience, vulnerability and adaptability becomes considerably less clear as research turns to analyses of larger, complex, globally teleconnected systems, where the main contribution of such concepts may lie in their metaphorical appeal to important aspects of interconnectivity and interdependence.  相似文献   
74.
The unpredictability of human behavior toward wildlife, coupled with changes in human behavior over space and time, are integral challenges of today's wildlife managers to meet administrative mandates. These challenges are exacerbated by extensive urban development and human population growth along with recent successes in wildlife conservation, leading to increasing encounters, and conflicts, between humans and wildlife. Thus, wildlife management is increasingly concerned with managing the co-existence of people and wildlife in a diminishing wild. However, attempting to analyze human–wildlife encounters, or solve human–wildlife conflicts, continues to be problematic. No structured behavior theory exists on how to address these management challenges. This study is a first attempt to do so through assembling and analyzing existing social-psychological, human-environment, and human–wildlife behavior theories and models in regard to their relevance to human–wildlife encounters. We illustrate the need to move from individualistic social and ecological approaches to an integrated complexity-theory based approach. We argue that human–wildlife encounters can only be understood and modified toward resilient relationships when treated as a complex social-ecological system. Key factors identified across literature impacting formation of positive and negative perceptions and behavior decision-making during an encounter are: cognition and emotions formed through beliefs and experiences across scales, barriers and benefits to specific behavior choices, and social thresholds. Using this multi-disciplinary approach, models and theories are drawn upon to develop the Integrated Adaptive Behavior Model of human–wildlife encounters.  相似文献   
75.
We develop a systems framework for exploring adaptation pathways to climate change among people in remote and marginalized regions. The framework builds on two common and seemingly paradoxical narratives about people in remote regions. The first is recognition that people in remote regions demonstrate significant resilience to climate and resource variability, and may therefore be among the best equipped to adapt to climate change. The second narrative is that many people in remote regions are chronically disadvantaged and therefore are among the most vulnerable to climate change impacts. These narratives, taken in isolation and in extremis, can have significant maladaptive policy and practice implications. From a systems perspective, both narratives may be valid, because they form elements of latent and dominant feedback loops that require articulation for a nuanced understanding of vulnerability-reducing and resilience-building responses in a joint framework. Through literature review and community engagement across three remote regions on different continents, we test the potential of the framework to assist dialogue about adaptation pathways in remote marginalized communities. In an adaptation pathway view, short-term responses to vulnerability can risk locking in a pathway that increases specific resilience but creates greater vulnerability in the long-term. Equally, longer-term actions towards increasing desirable forms of resilience need to take account of short-term realities to respond to acute and multiple needs of marginalized remote communities. The framework was useful in uniting vulnerability and resilience narratives, and broadening the scope for adaptation policy and action on adaptation pathways for remote regions.  相似文献   
76.
Climate change and resultant coastal erosion and flooding have been the focus of many recent analyses. Often these studies overlook the effects of manmade modifications to the coastline which have reduced its resilience to storm events. In this investigation, we integrate previous reports, historical photo analysis, field work, and the application of numerical models to better understand the effects of Wilma, the most destructive hurricane to affect Cancun, Mexico. Huge waves (of significant height, >12 m), long mean wave periods (>12 s), devastating winds (>250 km/h), and powerful currents (>2 m/s) removed >7 million cubic meters of sand from the Cancun beach system, leaving 68% of the sub‐aerial beach as bedrock, and the rest considerably eroded. Numerical simulations show that the modifications to the barrier island imposed by tourist infrastructure have considerably increased the rigidity of the system, increasing the potential erosion of the beach under extreme conditions. If there were no structural barriers, a series of breaches could occur along the beach, allowing exchange of water and alleviating storm surge on other sections of the beach. If the effects caused by anthropogenic changes to Cancun are ignored, the analysis is inaccurate and misleading.  相似文献   
77.
伍国春  高孟潭 《中国地震》2014,30(3):317-323
本文关注社会组织在防震减灾中的作用,通过分析壹基金在雅安地震后的救援以及恢复重建活动,明确社会组织参与灾害救助已经从九江地震后的萌芽状态、汶川地震的积极参与发展到雅安地震后通过调节机制而发挥作用的阶段.这表明社会组织的资源动员模式已经形成.加强和社会组织的合作,是提高地震重点监视防御区灾害治理能力的重要途径.  相似文献   
78.
This paper provides empirical evidence to support existing anecdotal studies regarding the mechanisms by which human communities become vulnerable to rapid changes in freshwater resources on the Seward Peninsula, Alaska. We interviewed adults, stratified by age, sex, and extended family, in Inupiat communities on the Seward Peninsula. Using categorical indices as part of a semi-structured interview we elicited a respondent's perception of the availability and quality of freshwater resources in their community as well as their perception of change in the availability and quality of freshwater during the period of their lifetime in that community. Significant relationships were observed between age groups for the perception of change in the availability of the local water source and the perception of change in its quality—older generations perceiving more change than younger age groups. These perceptions of change were examined with respect to recent historic changes in precipitation and temperature on the Seward Peninsula. These findings suggest that individual perceptions are instrumental in determining whether or not change merits response. The findings also provide evidence that oral traditional knowledge systems have shifted from continuous to discontinuous transmission, distancing the users from traditional resources. We discuss the role of collective knowledge, through the transmission of knowledge from elders to subsequent generations, in aiding the development of a community's ability to note and respond to changes in critical natural resources.  相似文献   
79.
The development and use of indicators is common practice in efforts to promote urban sustainability. Indicators used to measure urban sustainability tend to focus narrowly on describing the current state of the urban system. Although a time series analysis using these indicators may lend insights into trends towards or away from certain ‘sustainability’ goals, existing indicators of urban sustainability do not provide information on the ability or the likelihood that the current system state can be maintained or improved over time. Indicators that incorporate a measure of system resilience would provide useful information on system sustainability. Through development of a new indicator, Water Provision Resilience (WPR), we provide an example of how measures of resilience could be incorporated into sustainability indicators. The new indicator adds six color codings to the existing indicator ‘percent of the population with access to safe water.’ Each color coding represents a measure of the ability of the water system to maintain or improve the current percent of the population with access to safe water in key areas of the water provision sector: supply, infrastructure, service provision, finances, water quality and governance. The metric is then applied to three cities. The goal in developing this metric is to provide a starting point for re-thinking the metrics used to measure progress and sustainability in order to incorporate the ability to absorb and adapt to stresses into sustainability analysis.  相似文献   
80.
This study explored how Territorial Use Rights for Fisheries (TURFs) functioned during the recovery from the devastating tsunami disaster which struck the Sanriku region in 2011, with a focus on abalone harvest, which is the most profitable resource managed by TURFs. During the winter of 2011–2012, only 36 of 51 managing bodies could harvest abalones because of a great shortage of boats. Recourse degradation was also feared, and the harbors were badly damaged. Of 27 managing bodies whose harvesting methods were known, 22 harvested collectively. Abalones are traded at high price and harvesting them requires skill; hence, it has always been done individually and competitively; collective harvesting conducted during this season was therefore quite exceptional. Eighteen managing bodies also handled distribution of the harvest, adopting flexible measures according to each community's circumstances. The collective action ended immediately after the urgent shortage of boats was alleviated. The diversity of natural resources managed by TURFs, autonomy of the fishing communities fostered by their remoteness and the nested structure of TURFs’ resource management enhanced the resilience of the fishing communities.  相似文献   
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