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1.
Social actors in arid regions must develop strategies to respond to available resources, which are scarce, variable, patchy and unpredictable relative to other regions. We explore our observations of relationships amongst people and organisations in Australian deserts using a stylised network model of the structure of social networks in arid systems. Results suggest that temporal resource variability drives increased network density, but with fewer strong ties; sparse populations drive a relatively higher proportion of strong ties, and that networks develop a hub configuration as resource endowments become more patchy spatially. These ideas highlight some issues that warrant improved understanding by actors seeking to enhance livelihoods and local resilience in these extreme environments.  相似文献   

2.
This paper explores the evolution of land use and natural resource management strategies over the past twenty to fifty years in a remote Sahelian region. The empirical example is Karagou village in SE Niger. Building on an in-depth survey from 1992 and a targeted, follow-up analysis of contemporary land use strategies in 2011, the change process is scrutinized.The analysis uses the conceptual lenses of land systems science, human–environmental timelines, and the notion of multiple exposures. Enabling and constraining conditions for local livelihoods in terms of the resource base (landscape, water, and population) are described. Results characterize how land use strategies have developed and how local people opportunistically use different landscape elements such as dune landscapes, valley bottoms (bas-fonds) and oases (cuvettes). Major concerns are rainfall variability, saturation of cropland, and perceived dwindling groundwater resources. It is concluded that the land use and livelihood strategies have remained remarkably stable in the face of the changing socio-ecological fringe conditions, but that this situation may hamper a sustainable transformation.  相似文献   

3.
灌区中居民点与水土资源邻近关系——以张掖绿洲为例   总被引:1,自引:1,他引:0  
王录仓  高静 《干旱区地理》2015,38(4):797-804
干旱区内陆河流域的核心在于水,核心区域在于绿洲。灌区是构成绿洲的最基本单元。论文应用最邻近距离指数(NNI),分析了张掖绿洲灌区中居民点与水浇地及渠系之间的空间耦合关系,结果表明:在张掖大小共39个灌区中,有22个灌区的NNI值<0.5,灌区中居民点总体表现为聚集分布态势,但空间差异明显,沿山灌区居民点聚集程度明显高于绿洲中腹灌区,映射出不同灌区水资源的基本约束力。从微观角度考察,居民点与水浇地、渠系、道路之间的平均临近距离从沿山独立灌区-绿洲边缘灌区-绿洲中腹灌区逐步增加,说明沿山灌区水浇地、渠系与居民点的关系更密切。灌区中居民点与渠系、水浇地表现出显著的"亲水型"和"亲地型","质点"(居民点)-"廊道"(渠系和路网)-"域面"(土地)之间存在非常密切的相互依存关系。  相似文献   

4.
The impacts of extreme weather events and climate variability on natural resource dependent farmers will further increase their vulnerability. This study describes how Adi farmers in Arunachal Pradesh (India) perceive and adapt to climate variability, and how this is influenced by gender and wealth. A total of 65 male and 71 female Adi farmers were interviewed or participated in focus group discussions. Both men and women have noticed there are fewer rainy days, longer summers, shorter winters and more erratic rainfall. However, some perceptions of change were gender and/or wealth class specific. Adi women noticed changes across areas they control including collecting forest foods, crop harvesting, and fermenting and storing of food. Men noted climate variability had made hunting wild game and marketing agricultural produce more difficult. Wealthy people were better placed to adapt to climate variability than poorer people because they could intensify their production systems. They switched to rainfed maize with improved varieties and horticultural cash crops which need more costly inputs. Wealthy people, particularly men, also received more advice and training than poorer people. Poorer farmers, particularly poor women, adapted predominantly by diversifying activities, such as using drought tolerant oil seeds and subsistence horticultural crops, accessing forest-based resources, rearing pigs and poultry, increasing fishing and the making of handicrafts. Storage, exchange and pooling of local resources were further strategies of the poor. This deeper understanding of Adi livelihood adaptation strategies will help increase their resilience by improving targeting of location specific extension services and adaptation policies.  相似文献   

5.
田间滴灌入渗与蒸发条件下土壤水盐分布特征   总被引:2,自引:1,他引:1  
2006年在新疆阿克苏阿瓦提丰收灌区通过田间试验,研究了滴灌入渗和蒸发条件下土壤水盐分布规律。结果表明:滴头流量增加时水平方向含水量增加,纵向含水量减小;滴头下方土壤含盐量与滴头流量成负相关关系,随着滴头流量的增加,盐分累积的深度依次减小;土壤盐分的淋洗效率和压盐深度均与灌水历时成正比;覆膜不仅对表层土壤含水量减小具有显著抑制作用,而且对表层土壤盐分累积有较好的抑制作用,不覆膜处理在0~10 cm深度处土壤盐分增加值最大,覆膜处理盐分增加值的最大值出现在20~30 cm深度处。  相似文献   

6.
The biophysical environment of rangelands in the arid and semi-arid lowland parts of Africa is customarily viewed as a homogenous entity. Such notion has encouraged employing a blanket management approach. However, there are perceptible variations within them which necessitate site-specific range management. This study has attempted to identify the variability of soil and forage attributes and assess the existing management practices of those resources in the Baro River plain, Ethiopia. Sample transects, representing pre- and post-fire conditions, were used to collect composite soil samples and vegetation attributes. Alongside the physical survey, a household survey was undertaken to validate the laboratory-generated information. The result showed significant differences of soil and forage attributes among different management regimes, distances from river course and dominant cover types. In general, the distribution of soil nutrients showed a 'distance decay effect', while the distribution of pH showed the reverse pattern. Application of heavy fire load and congested grazing are the principal range management related factors. About 80 per cent of sample pastoralists employ heavy fire without due consideration for the sustainability of the range resource and without considering the local variability. Recognition of site-specific information is the key to effective management of range resources in the study area.  相似文献   

7.
陈玲  谢正观 《干旱区地理》2007,30(2):301-306
干旱区城镇体系的发展强烈受制于区域特有的自然地理、资源、土地类型等自然约束条件,它们是人口、产业和城镇发展布局的地理基础。干旱区城镇体系构建的优化模式选择,应充分考虑区域的自然、社会经济特征以及区域的范围大小。在城镇体系规划编制过程中充分贯彻非均衡发展思想,重点发展中心城市和开发区,构建合理的“集聚型城镇体系”是符合干旱区的最佳选择。结合阿拉善左旗县域城镇体系规划编制进行分析,提出其未来区域城镇体系的发展应该坚持非均衡发展与优势区位优先开发的道路,通过功能分区、“轴线”的打造、“极点”的快速壮大加快空间集中化进程。  相似文献   

8.
Research within geography and related disciplines has directed much attention to the coupled interactions between social and ecological systems. These studies have usefully analyzed the multifaceted, temporal, and scalar dimensions of human–environment interactions and how future environmental change will continue to challenge human resource needs. Political ecology research has also made contributions in this regard, particularly by emphasizing livelihood systems, impacts of conservation and development, agricultural production, and environmental governance. Yet although political ecology research has contributed to socioecological systems scholarship, much of this work has been situated within dryland environments or marine ecosystems that have particular biophysical features. Comparatively, wetland environments that experience dynamic flooding regimes warrant further attention from political ecology. This article engages with the findings from an ongoing research project that is evaluating the impacts of flooding variability for rural livelihoods in the Okavango Delta of Botswana. We outline some of the main findings from this work by concentrating on two themes central to political ecology: access and governance. We conclude by arguing that the Okavango Delta should be understood as a hydrosocial waterscape that encompasses a variety of socioecological relationships within the region, as well as the power relations operating at a variety of scales that both produce and govern them.  相似文献   

9.
Zonation of landscapes is generally based on broad scale biophysical data, field surveys, imagery and expert knowledge. Such zonation represents a static view of the environment and does not reflect dynamics and function. Arid environments are however often highly dynamic, and spatial and temporal patterns may be expressed over long periods of time. These dynamics need to be understood for management. Our aim is to understand the dynamics and functional response of vegetation in the Australian arid zone, and use this to inform and potentially improve the currently employed stratification. Principal component analysis of 25 years of satellite imagery identified underlying factors influencing patterns of arid vegetation growth, and regions of similar long-term response. Dominant factors of variation were identified as the spatial distribution of total vegetation growth, seasonality of growth, magnitude of seasonal variability in growth, and regularity of variation in growth. Additional variation resulted from episodic vegetation growth of limited spatial extent and duration. Classes expressing these functional components were compared with the existing biogeographical regions, revealing agreement in some instances, and in other cases adding information previously not available. The study demonstrates a new approach to Australian landscape zonation that has potential for much wider application.  相似文献   

10.
Due to increasing anthropogenic habitat alteration, fragmentation, and loss, the analysis of how, when, and why animals select particular habitats has become a central issue in ecology and biogeography. Animals adapt to spatiotemporal variability in resources either by tracking these resources or by plasticity in behavior to cover their needs, leading to three important implications: movement, temporal variation, and individual trade-offs leading to intra-species variability, all of which are directly linked to the use of space by animals. Based on GPS-tracking of domesticated reindeer in southern Norway, the authors addressed these issues by analyzing movement patterns and space use simultaneously across different temporal and organizational scales. Emerging information about the space use by reindeer was found explicitly linked to scaling relations, reflecting the matter of scale as having important functional implications rather than solely being a technical question of extent and resolution. Adding movement into the analysis of space use further advances the necessary functional perspective on space use. The authors conclude that scaling not only space but also time and the organizational level, in combination with accounting for different behavioral states, brings biogeography closer to a process-based view, rather than solely pattern-based view.  相似文献   

11.
干旱区水资源费的构成与确定   总被引:5,自引:2,他引:3  
干旱区水资源的稀缺性,使得确定缺水地区合理的水价体系,制定有效的水价政策,充分体现水资源的高"价值",成为合理利用水资源急需解决的问题。从分析水资源费的构成要素,并从边际机会成本的角度对水资源的价格进行了探讨,认为水资源的价格不是由其平均机会成本,而是由其边际机会成本决定的,水资源使用者所付的价格应等于社会负担的自然资源利用与耗竭的代价——边际机会成本。  相似文献   

12.
区域科技资源配置能力的时空分异研究   总被引:1,自引:0,他引:1  
科技资源作为第一资源,如何对其进行优化配置是各地区科技管理和科技政策工作的核心问题。根据科技资源的内涵与结构,利用1999-2011年中国31个省市区科技资源的基础数据,在构建区域科技资源配置能力评价指标体系的基础上,科学评价各地区的科技资源配置能力,并利用基尼系数与锡尔指数研究了各地区科技资源配置能力的差异;然后进一步运用探索性空间数据分析(ESDA),直观的反映各个省区科技资源配置能力的的空间集聚特征、集聚类型和显著性水平。结果表明,虽然近年来我国区域科技资源整体配置能力都有了较大提升,但是其区域分布的空间格局并没有根本性的改变;另外,中国科技资源配置能力的空间差异与区域发展的内部差异、区间差异有很大的关系,东部地区的地带内差异是构成区域差异的主要因素。  相似文献   

13.
14.
“行政区划本身也是一种重要资源”的理论创新与应用   总被引:1,自引:1,他引:0  
王开泳  陈田  刘毅 《地理研究》2019,38(2):195-206
行政区划是国家治理体系和组织结构的基本形式,也是中央政府统治和管理全国各地的有效手段,是事关国家政治、经济和社会发展全局的重大战略问题。就“行政区划本身也是一种重要资源”的论断进行多视角的分析,提出“行政区划资源论”这一全新的理论解读。分别从空间、权力、行政和政策角度探讨行政区划的资源属性,并从行政资源的空间配置、生产要素的优化配置、权力资源的空间整合、空间资源的优化重组和政策资源的空间载体等多个角度剖析行政区划的资源效应,最后提出应当将“行政区划资源论”这一新论断积极应用至主体功能区规划、空间规划、空间治理体系建设等实践领域,完善目前行政区划设置和调整的思路与要求,建立健全与国家发展战略及综合配套改革相适应的行政区划体系和管理框架。  相似文献   

15.
Many least-wealthy, rural, remote and resource-poor small island communities are unlikely to benefit from high-profile global water improvement initiatives. Their small landmasses, geologic composition, geography, social and technological isolation, colonial history, and weak educational and financial resources constitute significant barriers to improving access to safe drinking water. This paper discusses the relatively unique position of such island societies in the international community, providing a case study of the Federated States of Micronesia that integrates data and information pertaining to water resources management and governance, spanning from the island village to national scale. A vision is offered regarding the interaction between small island human and biophysical water systems, manifesting ways to pursue water resource development to improve public health which are constructed to be economically, physically and culturally sustainable.  相似文献   

16.
Extensive herding is an important activity in northern Cameroon, in terms of both the local social economy and local land management. However, this activity is strongly linked to the availability and accessibility of fodder resources. Due to territorial processes, such as land clearance and wood harvesting, this resource is receding and pasturelands are becoming fragmented. Herders are facing new challenges to secure their livelihoods, and, in this context, fodder trees are emerging as a key resource, allowing herds to subsist up to the end of the dry season. Increasingly, trees are playing a significant part in the herders' strategies to feed their herds in time and space and to 'root' their activities to particular lands. This trend requires an analysis of the importance of fodder trees in the definition of territorial strategies operated by herders in northern Cameroon, in the context of various herding systems (nomadic herding, agro herding using transhumance, and settled agro herding). A discussion of herding strategies needed to address the decreasing access to fodder resources highlights the problems of current extensive herding systems and leads to proposed alternatives.  相似文献   

17.
How mining companies overcome the problems faced by the fixity of resources and how they might come to exercise influence in societies which appear to be mostly post-industrial are complex questions of political geography. This is not least the case for a region such as the Pilbara—an iron ore site isolated from metropolitan centres—in Australia—a country isolated from many global centres and markets. At the same time, local struggles in this resources site have been profoundly influential in the making of a national neoliberal industrial relations agenda. Building on other scholarship on the Pilbara, but here re-emphasising the local scale and the details of work and regulation, provides a way to assess the place's wider importance. The Pilbara is a site of thoroughly transformed industrial relations, from a union space when export mining began in the 1960s to an employer stronghold today. Policy makers delivered changes to facilitate the remaking of employer power in workplaces in and beyond mining. This resource periphery has therefore been central to the remaking of national policy regimes.  相似文献   

18.
Humans perceive and evaluate environments affectively. Some places are experienced as unsafe, while some others as attractive and interesting. These affective responses to environments influence people’s daily behavior and decision-making in space, e.g., choosing which route to take, or which place to visit. In this article, we report on a methodology of using people’s affective responses to environments for enhancing computer-based route planning. More specifically, we explore a crowdsourcing approach to model and collect people’s affective responses to environments; an Affect-Space-Model and a mobile application are developed to facilitate this crowdsourcing approach; a routing algorithm (named AffectRoute) is then proposed to aggregate and integrate the collected data for automatic route planning. Evaluation with human participants shows that the routes generated by considering people’s affective responses to environments are significantly preferred over the conventional shortest ones, which are employed in car navigation systems and many online route planners. In conclusion, considering people’s affective responses to environments contributes to the improvement of automatic route planning. The proposed method can be integrated into existing route-planning services (e.g., location-based services) to provide users with more satisfying routing results.  相似文献   

19.
A revised set of propositions about ecology in arid Australia is presented, based on research literature since publication of Stafford Smith and Morton (1990). Fourteen propositions distil our argument that most features of the Australian deserts are explicable in terms of two dominant physical and climatic elements: rainfall variability, leading to extended droughts and occasional flooding rains; and widespread nutrient poverty. Different landscapes within the arid zone show these features to varying degrees, and so it is important to think about different places separately when considering our propositions. Plant life-histories strongly reflect temporal patterns of soil moisture; because Australian deserts receive more variable rainfall than most others, there is a distinctive spectrum of life-histories. Low levels of phosphorus (together with abundant soil moisture on irregular occasions) favour plants producing a relative excess of carbohydrate (C). In turn, C-rich plant products sometimes lead to fire-prone ecosystems, assemblages dominated by consumers of sap and other C-based products, and abundant detritivores (particularly termites). Fluctuations in production due to variable rainfall provide openings for consumers with opportunistic life-histories, including inhabitants of extensive but ephemeral rivers and lakes. Most consumer species exhibit some dietary flexibility or utilise more dependable resources; these strategies give rise to greater stability in species dynamics and composition of assemblages than might first be imagined under the variable rainfall regime. Aboriginal people have had long-standing ecological influence as they accessed resources. For each proposition we suggest the extent to which it is ‘different’, ‘accentuated’ or ‘universal’ in comparison with other deserts of the world, recognising that this categorisation is in need of critical testing. Further tests of each proposition are also suggested to fill the many gaps that still exist in our knowledge of the structure and functioning of Australia’s deserts.  相似文献   

20.
In this paper we summarize five experiments that were designed to investigate how tactile maps contribute to the cognitive maps of people with visual impairments. In two experiments we demonstrated that tactile maps can contribute to peoples' ability to learn a route through an unfamiliar area. From the results of two further studies, we argue that compared to people with sight, people with visual impairments have greater difficulty encoding information from a map. We considered this directly in a fifth experiment by investigating how people with visual impairments search and learn a map. We found that they used less efficient strategies than people with sight. We conclude that tactile maps are an important source of geographical information when people need to learn about new environments, but we also point out that to benefit most from tactile maps people need to encode the map information as effectively as possible. As people with visual impairments do not always use the most appropriate encoding strategies we suggest that tactile map users might benefit from greater experience and training in map encoding strategies.  相似文献   

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