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1.
Expanding beyond narrow approaches of understanding postapartheid space, this research analyzes the social relations contributing to land use patterns and livelihood decisions as manifestations of the coproduction of space. Drawing on a detailed livelihood and land‐change analysis case study of Polokwane, South Africa, it is argued that combinations of social processes across scales contribute to the production of peri‐urban South Africa and offer an uncommon mixed‐methods approach by combining qualitative ethnographic interviews, quantitative survey data, and land‐cover change detection. The peri‐urban interface is coproduced as individuals participate in multiple livelihood activities (wage labor, businesses, social programs) and changing land use patterns (residential, urban, mixed use) through negotiations at multiple scales—from macrolevel economic policy to local labor regimes.  相似文献   

2.
生态补偿方式对农户可持续生计影响分析   总被引:1,自引:0,他引:1  
对长汀县2000年以来的生态补偿措施进行分类,总结出各生态补偿方式的具体形式和补偿客体;并基于可持续生计分析框架,系统阐述了各生态补偿方式对农户生计资本、生计策略和生计结果的影响.结果表明,现金补偿部分缓解了因封山育林等措施对农户生计造成的不利影响;实物补偿增强了主要参与农户的物质资本,并确定了以农业为主的生计策略和相对稳定的纯收入;政策补偿主要使主要参与农户获得具有稳定产权的山地资源;技术补偿和产业补偿的作用相对较弱.最后,为增强今后各类农户可持续生计,提出技术补偿、政策补偿和产业补偿方式方面的具体对策.  相似文献   

3.
Construction of dams affects the livelihoods of the population living along the dammed river. There is a need for more studies to guide dam development policies and management to safeguard the livelihoods of local river users. This paper examines the effects of dams on the socio-economic livelihoods of downstream communities by drawing on the Kpong Dam in Ghana constructed from 1979 to 1982 with the goal of supplying energy and for irrigation purposes. Primary data were collected in resettled and non-resettled downstream communities using a mixed-research approach. This case study highlights how the Kpong Dam has affected the downstream river-dependent population whose livelihoods, particularly farming and fishing revolved around the seasonal flow regimes of the Volta River. Our study challenges the general perception that dams increase agricultural production by illustrating that developing ancillary facilities such as irrigation schemes as part of dam projects can enhance all-year-round agricultural production to improve food and income security of downstream households only when constraints such as lack of farm inputs are addressed. To safeguard livelihoods and limit the social impacts of dams, compensation schemes and alternative livelihood activities should be designed to include resettled and non-resettled communities along the downstream areas affected by dam projects.  相似文献   

4.
Urban poverty is invariably linked to sociospatial dimensions of livelihood strategies. Gendered social relations, for example, have been seen to impact the ability of females to access resources, to gain assets, and to engage in viable income‐generating activities. Focussing on the livelihood strategies of the urban poor as they intersect with neoliberal economic reforms in contemporary Ghana, this paper draws on a field‐based survey of porters in Accra, mostly migrants from rural agricultural northern Ghana, whose primary livelihoods derive from transporting goods for clients in congested market areas of the urban industrial south. The paper highlights the gendered aspects of porters' livelihood experiences such as differences in migration patterns, reliance on physical labour and living conditions, which relatively few analyses have examined, especially as these relate to wider socioeconomic processes. The study illustrates how this perspective is important to understand the intersection of livelihood strategies, gender and national economic reforms in promoting both rural and urban development.  相似文献   

5.
分析了盘锦芦苇湿地形成、芦苇湿地生态系统服务功能价值、芦苇产业现状,针对目前盘锦芦苇湿地存在的主要问题,提出了盘锦芦苇湿地可持续发展对策,促进实施科技兴苇战略,实现产业增效、职工增收,最终达到人与自然的和谐发展。  相似文献   

6.
生计安全研究的可视化分析   总被引:2,自引:2,他引:0  
苏飞  应蓉蓉  黄建毅  李博  朱赛颖  莫潇杭 《地理科学》2018,38(12):2058-2065
以Web of science 核心库中1991~2016年间收录主题为“livelihood security”的文献为基础,应用CiteSpace软件,采取突现词分析、关键词共现分析、文献共被引分析等方法对生计安全研究进行可视化分析。研究发现,干旱、健康、妇女、艾滋病、粮食安全、难民等是生计安全研究的前沿领域;生计安全研究热点主要包括生计结果类、生态环境类、生计策略类和重点地区类;生计安全研究的知识基础主要包括粮食安全、海洋资源、气候变化适应性等研究领域;从研究内容来看,中国生计安全研究主要包括自然资源与粮食安全、自然灾害与生计安全、快速城镇化与生计安全、气候变化与生计安全等4个方面。  相似文献   

7.
Water‐related diseases continue to pose major threats to children's survival and well‐being in many places in the developing world. This article develops a theoretical perspective on the ways in which children's vulnerability to water‐related disease hazard is produced within the everyday circumstances of livelihood and child care. Central to this analysis is the role that household resources play in mediating or shaping particular microenvironments of health risk. Further, the effects of local geographies of gender on how household resources are accessed and on how child care is structured are examined. Children's vulnerability is evaluated in a community in the District of Gilgit in northern Pakistan, a region presently undergoing tremendous social and economic transformation. The case study highlights household‐level response and adaptation to child health risks associated with diarrheal disease transmission and infection in this mountain environment. The case study draws from ethnographic fieldwork involving qualitative household microstudies and interviewing to elicit mothers' resource and risk‐response strategies in the context of changes in livelihood systems and household dynamics.  相似文献   

8.
In rural parts of the global South, livelihoods are diversifying away from agriculture. Nevertheless, agriculture typically still remains the backbone of rural life and is usually considered the prime source of economic security, social prestige and self‐identity. The task of narrating these somewhat contradictory processes in a conceptually coherent fashion has proven a major challenge for research. This paper responds to this problem by deploying an adapted version of Andrew Dorward's schema of households ‘hanging in, stepping up or stepping out’ of their landed interests. Dorward's middle‐ground theory provides an appropriate analytical vehicle for capturing the vagaries and situated complexities of the land‐livelihoods nexus. However the theory fails to fully appreciate the extent to which household livelihood decision making rests on complex entanglements that leverage land‐based and nonfarm activities against one another. We demonstrate the critical importance of these processes through the results of in‐depth interviews with 32 households in two north Indian villages. These interviews lead us to propose that land factors in livelihood aspirations in three fundamental ways: an arena for interpenetrated agrarian and nonagrarian livelihood streams; a base for social reproduction; and a bulwark of food (and by extension, livelihood) security through own‐production capabilities.  相似文献   

9.
10.
Sea‐level changes provide an important control on the interplay between accommodation space and sediment supply, in particular, for shallow‐water basins where the available space is limited. Sediment exchange between connected basins separated by a subaqueous sill (bathymetric threshold) is still not well understood. When sea‐level falls below the bathymetric level of this separating sill, the shallow‐water basin evolution is controlled by its erosion and rapid fill. Once this marginal basin is filled, the sedimentary depocenter shifts to the open marine basin (outward shift). With new accommodation space created during the subsequent sea‐level rise, sediment depocenter shifts backwards to the marginal basin (inward shift). This new conceptual model is tested here in the context of Late Miocene to Quaternary evolution of the open connection between Dacian and Black Sea basins. By the means of seismic sequence stratigraphic analysis of the Miocene‐Pliocene evolution of this Eastern Paratethys domain, this case study demonstrates these shifts in sedimentary depocenter between basins. An outward shift occurs with a delay that corresponds to the time required to fill the remaining accommodation space in the Dacian Basin below the sill that separates it from the Black Sea. This study provides novel insight on the amplitude and sedimentary geometry of the Messinian Salinity Crisis (MSC) event in the Black Sea. A large (1.3–1.7 km) sea‐level drop is demonstrated by quantifying coeval sedimentation patterns that change to mass‐flows and turbiditic deposits in the deep‐sea part of this main sink. The post‐MSC sediment routing continued into the present‐day pattern of Black Sea rivers discharge.  相似文献   

11.
不同补水条件下黄河三角洲湿地恢复情景模拟   总被引:6,自引:1,他引:5  
黄翀  刘高焕  王新功  葛雷  范晓梅  王瑞玲  单凯 《地理研究》2010,29(11):2026-2034
针对黄河三角洲湿地退化现状,设计了三种湿地修复水量预案。利用水文模型SOBEK和地下水模型Visual Modflow对不同补水预案下湿地水文过程进行模拟,将水文模拟结果与湿地立地条件、植被条件在景观决策支持模型LEDESS框架下进行集成,对三种补水预案下湿地修复情景进行模拟和评价。研究表明,对黄河三角洲湿地的恢复,根据区域湿地条件差异,其恢复目标及所需要的适宜水量也有所不同。一千二管理区宜采用最大引水预案,提高涉禽鸟类的生境适宜性;黄河口管理区宜采用最小水量预案,同时应降低生境干扰以改善栖息地质量;对于大汶流管理区,中等水量对于涉禽类和游禽类的生境都有较大改善。本研究将水文过程与景观过程进行集成,利用情景模拟方法,为湿地恢复决策提供一种新的尝试。  相似文献   

12.
Lead roasting firms are operating through Indonesia's coffee exporters to introduce voluntary sustainability standards (VSS) in an attempt to secure supply, and to simultaneously meet corporate social responsibility requirements, even as empirical studies continue to show uncertain benefits for producer livelihoods. Value chain interventions like VSS, however, are not rolled out over a blank canvas, and many contributing factors determine their overall impact on livelihoods, particularly the local institutional environment. This study assesses the extent to which variability of empirical outcomes is determined by the institutional environment, by identifying specific processes through which VSS interact with pre‐existing social, political and economic institutions to influence livelihood outcomes. These include: firm‐specific corporate strategies (including producer training); livelihood strategies of households (including access to assets); government programs; and local political economy, as manifest particularly through patronage between traders and suppliers. VSS have thereby become an additional institutional layer shaping livelihood strategies and regional development outcomes, best viewed as providing access to a new social network that may be exploited by producers. The interaction between VSS programs, livelihood strategies and pre‐existing institutional environments in a particular place often dictates the variable outcomes for producers, making attribution of impact causation to VSS enrolment problematic.  相似文献   

13.
梳理产业选择与培育的经验,分析产业发展对农户生计的影响,对于促进生态移民区的乡村产业振兴、农户生计恢复与可持续发展具有重要意义。论文以中国最大单体移民迁入区宁夏吴忠市红寺堡区为研究区,针对4大乡村产业各选1个样本村,采用问卷调查法和半结构访谈法获取数据,在比较不同产业投入产出效益的基础上,探究不同产业发展对移民生计产出、生计资本及生计策略的影响。结果表明:① 红寺堡区的乡村产业已呈现出由传统粗放型向高效集约型转型的特征,但产业链短、抵御市场风险和灾害能力偏低的问题仍然突出;② 乡村产业发展对农户收入有明显的提升作用,但影响程度与产业类型、农户参与度密切相关,已完成产业转型的农户的生计资本总量远高于其他农户,生计资本结构存在明显差异;③ 不同产业村的农户优势生计模式差异明显,产业发展对农户生计的支撑力度仍有待提高。乡村振兴背景下,亟待培育新型经营主体,引导小农户与现代农业产业有机衔接,推动农户深度融入乡村产业链并长效受益,全面释放乡村产业多元化的功能;同时,继续对存在产业转型困难的农户,通过资金扶持、技术培训、托管代养等不同形式开展针对帮扶,帮助其建立可持续生计体系。  相似文献   

14.
Careful assessment of basin thermal history is critical to modelling petroleum generation in sedimentary basins. In this paper, we propose a novel approach to constraining basin thermal history using palaeoclimate temperature reconstructions and study its impact on estimating source rock maturation and hydrocarbon generation in a terrestrial sedimentary basin. We compile mean annual temperature (MAT) estimates from macroflora assemblage data to capture past surface temperature variation for the Piceance Basin, a high‐elevation, intermontane, sedimentary basin in Colorado, USA. We use macroflora assemblage data to constrain the temporal evolution of the upper thermal boundary condition and to capture the temperature change with basin uplift. We compare these results with the case where the upper thermal boundary condition is based solely upon a simplified latitudinal temperature estimate with no elevation effect. For illustrative purposes, 2 one‐dimensional (1‐D) basin models are constructed using these two different upper thermal boundary condition scenarios and additional geological and geochemical input data in order to investigate the impact of the upper thermal boundary condition on petroleum source rock maturation and kerogen transformation processes. The basin model predictions indicate that the source rock maturation is very sensitive to the upper thermal boundary condition for terrestrial basins with variable elevation histories. The models show substantial differences in source rock maturation histories and kerogen transformation ratio over geologic time. Vitrinite reflectance decreases by 0.21%Ro, source rock transformation ratio decreases 10.5% and hydrocarbon mass generation decreases by 16% using the macroflora assemblage data. In addition, we find that by using the macroflora assemblage data, the modelled depth profiles of vitrinite reflectance better matches present‐day measurements. These differences demonstrate the importance of constraining thermal boundary conditions, which can be addressed by palaeotemperature reconstructions from palaeoclimate and palaeo‐elevation data for many terrestrial basins. Although the palaeotemperature reconstruction compiled for this study is region specific, the approach presented here is generally applicable for other terrestrial basin settings, particularly basins which have undergone substantial subaerial elevation change over time.  相似文献   

15.
The Hazar Basin is a 25 km‐long, 7 km‐wide and 216 m‐deep depression located on the central section of the East Anatolian Fault zone (eastern Turkey) and predominantly overlain by Lake Hazar. This basin has been described previously as a pull‐apart basin because of its rhombic shape and an apparent fault step‐over between the main fault traces situated at the southwestern and northeastern ends of the lake. However, detailed structural investigation beneath Lake Hazar has not been undertaken previously to verify this interpretation. Geophysical and sedimentological data from Lake Hazar were collected during field campaigns in 2006 and 2007. The analysis of this data reveals that the main strand of the East Anatolian Fault (the Master Fault) is continuous across the Hazar Basin, connecting the two segments previously assumed to be the sidewall faults of a pull‐apart structure. In the northeastern part of the lake, an asymmetrical subsiding sub‐basin, bounded by two major faults, is cross‐cut by the Master Fault, which forms a releasing bend within the lake. Comparison of the structure revealed by this study with analogue models produced for transtensional step‐overs suggests that the Hazar Basin structure represents a highly evolved pull‐apart basin, to the extent that the previous asperity has been bypassed by a linking fault. The absence of a step‐over structure at the Hazar Basin means that no significant segmentation boundary is recognised on the East Anatolian Fault between Palu and Sincik. Therefore, this fault segment is capable of causing larger earthquakes than recognised previously.  相似文献   

16.
Sedimentary basins are affected by a large number of forcing factors during their evolution and as a result, it is often difficult to isolate the contribution of each individual factor. Many forcing factors are temporally and spatially heterogeneous; they do not affect all parts of the basin in the same way and at the same time. We show that this heterogeneity can be used to identify the contributions of forcing factors by comparing various parts of a basin. This approach is applied to the Pannonian Basin, a back‐arc basin located in Central Europe. In the basin, the amounts of crustal extension, tectonic inversion and sediment influx varied in space and time, while the connection with the marine realm fluctuated. In this study we focus on two currently unresolved issues: firstly, we establish by what processes and from what directions the basin was filled in, and secondly, we investigate whether the basin was affected by the Messinian Salinity Crisis. The analysis of seismic and well data in the previously less studied SE part of the basin demonstrate that progradation occurred from the southern and eastern basin margins, complementing the previously described progradation from the northwestern and northern basin margins. Elsewhere in the basin, an unconformity observed in the progradational basin infill is intensely debated to be the result of either the Messinian Salinity Crisis (MSC) or basin inversion. Having the advantage of minor Pliocene–Quaternary amounts of inversion in the studied part of the basin we show that no regional unconformity is present in the studied stratigraphic interval, which implies that the effects of the MSC on the basin were minor. We infer that being aware of the fact that the effects of relative sea/lake‐level fluctuations may vary significantly across a basin is critical for understanding the evolution of semi‐enclosed basins.  相似文献   

17.
《Basin Research》2018,30(4):650-670
The Palaeogene Isparta Basin of southwestern Anatolia formed between two convergent arms of the Isparta Bend orocline of the Tauride orogen. The origin of this tightening orocline is hypothetically explained in plate‐tectonic terms. Basin sedimentation commenced on a down‐warped Mesozoic carbonate platform of a crustal block accreted at the end of Cretaceous to the southern margin of the Anatolian plate. The basin earliest deposits are Palaeocene reddish mudstones with a fossil‐barren condensed basal part and increasingly interspersed with thin calcarenitic turbidites towards the top. The supply of turbiditic sediment to the basin plain subsequently increased, as the upper‐bathyal basin plain became surrounded from both sides by a narrow littoral shelf with an advancing turbiditic slope ramp. A major forced regression occurred at the end of Bartonian, causing incision of subaerial to submarine valleys up 600 m deep, filled in with gravelly to sandy turbidites and debrisflow deposits during the subsequent rise of relative sea level. The half‐filled valleys were re‐incised due to a Rupelian forced regression and were fully filled with fluvio‐deltaic bayhead deposits during a final marine transgression that re‐established the basin‐margin biocalcarenitic shelf. The littoral environment then expanded across the shallowing basin, as the basin axial zone was up‐domed and eroded to bedrock level at the end of Oligocene and the basin was tectonically inverted in Miocene. The pattern of intra‐orocline foreland sedimentation documented by this case study provides tentative criteria for the recognition of synorogenic oroclines and for their distinction from post‐orogenic oroclines.  相似文献   

18.
Exhumed basin margin‐scale clinothems provide important archives for understanding process interactions and reconstructing the physiography of sedimentary basins. However, studies of coeval shelf through slope to basin‐floor deposits are rarely documented, mainly due to outcrop or subsurface dataset limitations. Unit G from the Laingsburg depocentre (Karoo Basin, South Africa) is a rare example of a complete basin margin scale clinothem (>60 km long, 200 m‐high), with >10 km of depositional strike control, which allows a quasi‐3D study of a preserved shelf‐slope‐basin floor transition over a ca. 1,200 km2 area. Sand‐prone, wave‐influenced topset deposits close to the shelf‐edge rollover zone can be physically mapped down dip for ca. 10 km as they thicken and transition into heterolithic foreset/slope deposits. These deposits progressively fine and thin over tens of km farther down dip into sand‐starved bottomset/basin‐floor deposits. Only a few km along strike, the coeval foreset/slope deposits are bypass‐dominated with incisional features interpreted as minor slope conduits/gullies. The margin here is steeper, more channelized and records a stepped profile with evidence of sand‐filled intraslope topography, a preserved base‐of‐slope transition zone and sand‐rich bottomset/basin‐floor deposits. Unit G is interpreted as part of a composite depositional sequence that records a change in basin margin style from an underlying incised slope with large sand‐rich basin‐floor fans to an overlying accretion‐dominated shelf with limited sand supply to the slope and basin floor. The change in margin style is accompanied with decreased clinoform height/slope and increased shelf width. This is interpreted to reflect a transition in subsidence style from regional sag, driven by dynamic topography/inherited basement configuration, to early foreland basin flexural loading. Results of this study caution against reconstructing basin margin successions from partial datasets without accounting for temporal and spatial physiographic changes, with potential implications on predictive basin evolution models.  相似文献   

19.
1INTRODUCTION Hydroponics(aGreekword,hydromeanswater andponos,labour),asoil-lessagriculture,isa termtobedescribedinseveralwaysinwhichplants cangrowwithoutsoil,byuseofaninertmedium whereplantcantakeupessentialnutrients,either fromwaterinwhichanutrientsolutionisaddedor fromorganicmaterialsthatexistsinthemedium.Thesemediacanbegravel,sand,peat,vermiculate,prelite,sawdustorotherplantmatters(organiccom ponents).Therefore,theprocessinwhichaquatic weedsaredumpedonwatertoconstructfloatingbed orart…  相似文献   

20.
阐述了目前盘锦芦苇湿地的生产现状,分析了制约芦苇产量的主要因素,提出了提高芦苇产量的有效对策,并全面分析了实施各项对策后产生的经济效益、生态效益和社会效益,以期为盘锦芦苇产业发展提供科学依据和实用技术指导。  相似文献   

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