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1.
《Geoforum》2016
Inspired by Ostrom’s concept of polycentric governance, this article aims to refine the analytical framework through which contemporary access to land is analysed. By drawing on extensive fieldwork and conducting a review of the existing literature on the making and implementation of Tanzania’s 1999 land reform, it challenges some of the main assumptions behind the land access and land grabbing literatures about the level at which agency is placed. Processes governing access to land are more contingent than they are most often depicted, involving actors at the local, national and international levels. National and local level actors are often more important than, in particular, the land grab literature tends to suggest. This implies that the state should be seen not merely as a site of ‘legitimate theft’, but also as one in which rights may be upheld. Based on the experience of Tanzania, the article suggests that analytical a priori assumptions about where agency is placed should be abandoned and replaced with empirical research into the relations between actors at all levels. 相似文献
2.
《Geoforum》2014
Most studies on the causes of deforestation have sought to link the phenomenon to specific economic, political, or demographic factors, usually through statistical or spatial-statistical modeling. However, generalizations about the link between deforestation and specific variables or classes of variables are of questionable validity. Another approach, one that is receiving growing attention, seeks instead to identify particular contexts or situations, as created by an array of interacting factors, which encourage forms of land use or other economic activity that can generate deforestation pressure. Such an approach was used in this study to explore recent trends and dynamics in the Petén region of northern Guatemala. The research found a number of regional and national scale factors that in combination have led to a process of de-agrarianization and dispossession among smallholders, while large scale, commercial activities in agriculture, ranching and plantation forestry increasingly dominate. Rapid land concentration, in conjunction with limited employment generation through emergent activities, is intensifying pressure on remaining areas of forest. A focus on two distinct areas within Petén reveals how broader-scale trends and features can have differing outcomes at the local level, with contrasting socioeconomic and environmental effects. Finally, the paper explores the implications of recent dynamics in Petén for both policy and theory in relation to deforestation, agrarian change, and regional development. Key factors and questions are highlighted that should be considered when exploring influences on regional socioeconomic and environmental conditions. 相似文献
3.
《Geoforum》2015
Agricultural land use in much of Brong-Ahafo region, Ghana has been shifting from the production of food crops towards increased cashew nut cultivation in recent years. This article explores everyday, less visible, gendered and generational struggles over family farms in West Africa, based on qualitative, participatory research in a rural community that is becoming increasingly integrated into the global capitalist system. As a tree crop, cashew was regarded as an individual man’s property to be passed on to his wife and children rather than to extended family members, which differed from the communal land tenure arrangements governing food crop cultivation. The tendency for land, cash crops and income to be controlled by men, despite women’s and young people’s significant labour contributions to family farms, and for women to rely on food crop production for their main source of income and for household food security, means that women and girls are more likely to lose out when cashew plantations are expanded to the detriment of land for food crops. Intergenerational tensions emerged when young people felt that their parents and elders were neglecting their views and concerns. The research provides important insights into gendered and generational power relations regarding land access, property rights and intra-household decision-making processes. Greater dialogue between genders and generations may help to tackle unequal power relations and lead to shared decision-making processes that build the resilience of rural communities. 相似文献
4.
Urbanization produces substantial land use changes by causing the construction of different urban infrastructures in the city region for habitation, transportation, industry, and other reasons. As a result, it has a significant impact on Land Surface Temperature (LST) by disrupting the surface energy balance. The objective of this paper is to assess the impact of land-use/land-cover (LU/LC) dynamics on urban land surface temperature (LST) of Bhubaneswar City in Eastern India during 30 years (1991–2021) using Landsat data (TM, ETM + , and OLI/TIRS) and machine learning algorithms (MLA). The finding reveals that the mean LST over the entire study domain grows significantly between 1991 and, 2021due to urbanization (β coefficient 0.400, 0.195, 0.07, and 0.06 in 1991, 2001, 2011, and 2021 respectively) and loss of green space (β coefficient − 0.295, − 0.025, − 0.125 and − 0.065 in 1991, 2001, 2011 and 2021 respectively). The highest class recorded for agricultural land (49.60 km2, accounting for 33.94% of the total land area) was in 1991 followed by vegetation (41.27 km2, 28.19% of the total land area), and built-up land (27.59 km2, 18.84% of the total land area). The sharp decline of vegetation cover will continue until 2021 due to increasing built-up areas (r = − 0.531, − 0.329, − 0.538, and − 0.063 in the 1991, 2001, 2011 and 2021 respectively). Built-up land (62.60 km2, accounting for 42.76% of the total land area, an increase of 35.01 km2 from 1991) as the highest class followed by water bodies (21.57%, 32.60 km2 of the land area), and agricultural land (31.57 km2, 21.57% of the land area) in 2021. Remote sensing techniques proved to be an important tool to urban planners and policymakers to take adequate steps to promote sustainable development and minimize urbanization influence on LST. Urban green space (UGS) can help improve the overall liveability and environmental sustainability of Bhubaneswar city.
相似文献5.
Recent years have seen an upsurge in the numbers of studies investigating the potential link between climate variability and conflict—and particularly so quantitative studies of this relationship—without reaching any consensus on causal pathways or main findings. This study sets out to explore what the main causes of conflict between resource-user groups in arid and semi-arid areas in Sub-Saharan Africa are, with a particular focus on renewable-resource scarcity. We conduct a comparative analysis of eleven high-quality case studies of the escalation into violence of disputes between pastoralists and farmers or pastoralists in the Western Sahel and East Africa. This enables us to identify the mechanisms underpinning the actors’ motivations. Our analysis shows that the nature of these conflicts is complex. They cannot be reduced to a stimulus (resource scarcity)–response (violence) relationship. We find that drought is a contributing factor in four of the conflicts, and that a poor rainy season plays a role in a fifth one. However, resource scarcity is never the most important cause and it does not explain well the differences in conflict intensity. The most important contributor to explaining different levels of intensity is when local autochthonous and exclusionary claims are coupled with national-level political processes. 相似文献
6.
《Geoforum》2017
Over the last decade, shifting strategies of capital accumulation have deepened the integration of land and associated primary commodities into circuits of investment. More than merely an economic revaluation of land, such integration involves an iterative rearrangement of the social and natural processes determining land’s material and symbolic qualities. Highlighting these shifts through a comparative study of investment processes for large-scale agricultural and extractive projects, we posit investment processes as assemblages proceeding in the context of different ontologies, valuations, and uses of land, which coalesce and compete with one other in complex ways, producing new spaces and subjectivities. Such assembling, we suggest, notably involves a discursive component involving the narration of the need for investment, an institutional component reforming regulatory arrangements, and an operational component enrolling labour, infrastructure, and ancillary resources associated with agricultural and extractive production. After examining each of these components in turn, we conclude with a discussion of tensions and contradictions inherent in ‘opening’ lands for investment and the business of harnessing agricultural and extractive resources. 相似文献
7.
The morphology of Vamanapuram river basin (VRB), southern Kerala, India has been studied by preparing longitudinal profiles from the source of VRB at Chemmunji Mottai (1,717 m) to its mouth at Muthalapallipozhy (Lakshadweep Sea). Survey of India topographical maps, Geocoded Satellite Imageries, Microsoft Excel and GIS software ILWIS 2.1 are used in this study. The morphometric analysis reveals that there are 1,489, 347, 79, 21, 6, 2 and 1 first-, second-, third-, fourth-, fifth-, sixth- and seventh-order streams, respectively, in VRB, which are responsible for the present-day landform genesis. The mean bifurcation value of VRB is 3.49. The Ponmudi hills receive the highest rainfall in VRB in the Western Ghats Region and Attingal, the lowest in the Coastal Strand Plain. The six land use and land cover profile sections show the distribution of land use–land cover with respect to elevation and depth to water level. The study reveals that mid and high lands generally occupy lower order streams up to fourth order and generally originate from linear ridge, hill crest, rocky slope (scarp face), side slope (S3)/slope 10–15° and hilly terrain. 相似文献
8.
《Geoforum》2014
In Ghana, the contested concepts of “land grabbing” and “land transaction” are strategically applied by proponents of critical and win–win discourses respectively to describe outcomes of land deals. Using case study methods and discourse analysis, this paper explores four cases of biofuels investments in Ghana and the implications of the choice of concepts used to represent them. Proponents of the critical discourse use the “land grabbing” concept to invoke imageries of “illegality”, “theft” and “food insecurity” when describing land deals. Consequently, some biofuels investments have been hampered in their potential to generate profit and local employment. The biofuel investors in this study, whose projects have been labeled “land grabbing”, therefore switched to food production to downplay public scepticism. Proponents of the win–win discourse portray biofuels investments as “pro-poor” projects and use the “land transaction” concept to pre-empt possible public criticisms in the media and elsewhere. Such representations of these biofuels investments are therefore mainly intended to pre-empt criticisms or attract public praise. Some projects with potentially promising outcomes have thus been terminated, while others with problematic outcomes have continued to be promoted. In contexts characterized by weak land regulations and ambivalence towards large-scale agriculture, the trajectory and outcomes of biofuels investments are often influenced by land deal representations drawn from global discourses and how they interact with pre-existing local discourses. 相似文献
9.
Nicol Morton 《《幕》》2008,31(4):420-422
The Jurassic is traditionally famous for shallow marine sediments that are often very fossiliferous, notably in Europe, where the standard chronostratigraphic subdivisions were established and defined. However, widespread marginal and non-marine Jurassic sediments are also known, and are of great importance for the wellpreserved terrestrial biotas they contain, as well as for their hydrocarbon and coal reserves. IGCP Project 506 is directed towards finding means of correlation between marine and non-marine Jurassic rocks, as a foundation for a better understanding of the evolution of the Earth during the Jurassic Period. 相似文献
10.
AntonioBrambati LauraCarbognin TullioQuaia PietroTeatini LuigiTosi 《《幕》》2003,26(3):264-268
The paper deals with the geological setting, history and subsidence of the Venetian Plain. Major attention is paid to the Pleistocene-Holocene stratigraphic sequence in the Lagoon of Venice, in relation to its origin that datesback to 6-7 kyr BP. Geological land subsidence, which played an important role in the origin and the evolution of the lagoon, and anthropogenic subsidence, that has recently assumed a major importance for the Venetian environment, are discussed. Considering also the sealevel rise, 23 cm loss in land elevation has occurred in the last century, leading to increased flooding events and environmental problems that require protective works. 相似文献
11.
Scaling struggles over land and law: Autonomy,investment, and interlegality in Myanmar’s borderlands
《Geoforum》2017
This article explores the relevance of spatial global legal pluralism—an emerging field at the interstices of geography, anthropology, and socio-legal studies—for research on the global land rush, and the study of land law and investment in particular. I argue that a focus on the spatial dimensions of law—coupled with attention to the interlegality, scalar politics, and spatio-temporalities of semi-autonomous law—offers important insights into the dynamic forces, actors, and stakes in the global land rush. In Myanmar, the prospects for peace—however tenuous—have led to an acceleration of land law development including the creation of ‘semi-autonomous land law’ by ethnic armed groups and activists in its borderlands. I discuss the ways in which such policies not only anticipate peace but seek to shape its political-economy over multiple spatio-temporalities. By recognizing both international human rights law and customary law, such ‘non-state’ laws bring these two scales into an intermediary legal jurisdiction, contributing to the sedimentation of Kawthoolei and Kachinland as political scales in their own right. 相似文献
12.
Anthropogenic climate change is the Earth's most serious large-scale environmental concern. While the projected changes of global temperatures, rainfall and surface water have been modelled in a sophisticated manner, the impact on groundwater resources is much less well constrained. In southeast Australia, the decrease in rainfall amount and an increase in temperature that are predicted by climate models are generally assumed to reduce the amount of recharge to the groundwater systems. However, the increase in recharge that has resulted from clearing of the native vegetation will almost certainly produce a greater impact on the groundwater system, increasing quantity and potentially improving quality. Additionally, the impact on recharge of changes to rainfall frequency rather than just total amount is not well documented. Overall our understanding of the impacts of climate change on groundwater systems is insufficiently advanced to make firm predictions. Indirect impacts of climate change, particularly the projected increased demand for groundwater or surface water to supplement surface water supplies also will have a major impact that may be greater than the direct effect of climate change. 相似文献
13.
Koohbanani Hamidreza Yazdani Mohammadreza Hosseini Sayyed Keivan 《Natural Hazards》2020,103(1):785-798
Natural Hazards - Due to excessive harvesting of underground water resources in many important aquifers inside Iran, ground subsidence is occurring at different speeds. In present study, InSAR... 相似文献
14.
Hashim Bassim Mohammed Al Maliki Ali Sultan Maitham A. Shahid Shamsuddin Yaseen Zaher Mundher 《Natural Hazards》2022,112(2):1223-1246
Natural Hazards - Urban land surface temperature (LST) is dependent on many factors, including land cover, building materials, urban density, and other human activities. The current study evaluated... 相似文献
15.
Land use and land cover changes are local and place specific, occurring incrementally in ways that often escape our attention. This study sought to detect changes in land cover in the Tema Metropolis of Ghana from 1990 to 2010. Multispectral Landsat Thematic Mapper data sets of 1990, 2000 and 2007 were acquired, pre-processed and enhanced. Unsupervised classification of the images was performed and six land cover classes (water, wetlands, closed vegetation, open vegetation, cropped lands, and built-up) were derived. The post-classification change detection technique was performed to derive the changes in land cover and their corresponding change matrices. Between 1990 and 2010, built-up areas expanded steadily to become the most prevalent land cover type in the metropolis, reducing vegetation cover dramatically. High population growth with its attendant rise in the demand for housing, and increasing commercial activities, were found to have influenced land cover changes over the period. 相似文献
16.
Hubert Wiggering 《Environmental Earth Sciences》2014,71(12):5037-5044
It is crucial that today’s land uses are not decoupled even further from prevailing site conditions. Quite the contrary, the site-adequate use of natural resources ought to be mandatory. This is provided for to a certain extent by the concept of multifunctionality and the exploitation of locational geological potential. Nevertheless, an appropriate course of action has yet to be taken. This can be achieved by applying an appropriate geo-based land use concept. To this end, however, from the scientific perspective alone, there has to be a new level of quality in the interaction between the various specialist disciplines to resolve the nexus problem and to achieve systemic approaches. The gap between the knowledge available in geology and the aspired land use concepts appears to be particularly large. A land use concept that pursues a systemic approach and refers to an adequate extent to geological knowledge provides options for future site-adequate land use as the basis for respective decision-makers or decision-making processes, not any longer conducted by political constraints or economic incentives only. 相似文献
17.
Flooding in urban area is a major natural hazard causing loss of life and damage to property and infrastructure. The major causes of urban floods include increase in precipitation due to climate change effect, drastic change in land use–land cover (LULC) and related hydrological impacts. In this study, the change in LULC between the years 1966 and 2009 is estimated from the toposheets and satellite images for the catchment of Poisar River in Mumbai, India. The delineated catchment area of the Poisar River is 20.19 km2. For the study area, there is an increase in built-up area from 16.64 to 44.08% and reduction in open space from 43.09 to 7.38% with reference to total catchment area between the years 1966 and 2009. For the flood assessment, an integrated approach of Hydrological Engineering Centre-Hydrological Modeling System (HEC-HMS), HEC-GeoHMS and HEC-River analysis system (HEC-RAS) with HEC-GeoRAS has been used. These models are integrated with geographic information system (GIS) and remote sensing data to develop a regional model for the estimation of flood plain extent and flood hazard analysis. The impact of LULC change and effects of detention ponds on surface runoff as well as flood plain extent for different return periods have been analyzed, and flood plain maps are developed. From the analysis, it is observed that there is an increase in peak discharge from 2.6 to 20.9% for LULC change between the years 1966 and 2009 for the return periods of 200, 100, 50, 25, 10 and 2 years. For the LULC of year 2009, there is a decrease in peak discharge from 10.7% for 2-year return period to 34.5% for 200-year return period due to provision of detention ponds. There is also an increase in flood plain extent from 14.22 to 42.5% for return periods of 10, 25, 50 and 100 years for LULC change between the year 1966 and year 2009. There is decrease in flood extent from 4.5% for 25-year return period to 7.7% for 100-year return period and decrease in total flood hazard area by 14.9% due to provisions of detention pond for LULC of year 2009. The results indicate that for low return period rainfall events, the hydrological impacts are higher due to geographic characteristics of the region. The provision of detention ponds reduces the peak discharge as well as the extent of the flooded area, flood depth and flood hazard considerably. The flood plain maps and flood hazard maps generated in this study can be used by the Municipal Corporation for flood disaster and mitigation planning. The integration of available software models with GIS and remote sensing proves to be very effective for flood disaster and mitigation management planning and measures. 相似文献
18.
A major development programme comprising 15 gas fields of the northern Adriatic Sea has recently been submitted to the Ministry
of the Environment, VIA Committee for the assessment of the environmental impact, by ENI-Agip, the Italian national oil company.
One of the largest reservoirs is Chioggia Mare, located about 10 km offshore of the Venetian littoral, with a burial depth
of 1000–1400 m. The planned gas production from this field is expected to impact the shoreline stability with a potential
threat to the city of Venice, 25 km northwest of the center of Chioggia Mare. To evaluate the risk of anthropogenic land subsidence
due to gas withdrawal, a numerical model was developed that predicts the compaction of both the gas-bearing formations and
the lateral/bottom aquifer (water drive) during a 13-year producing and a 12-year post-production period, and the transference
of the deep compaction to the ground surface. To address the uncertainty of a few important hydromechanical parameters, several
scenarios are simulated and the most pessimistic predictions obtained. The modeling results show that at most 1 cm of land
subsidence over 25 years may be expected at the city of Chioggia, whereas Venice is not subject to settlement. If aquifer
drawdown is mediated by water injection, land subsidence is arrested 5 km offshore, with the Chioggia littoral zone experiencing
a rebound of 0.6–0.7 cm.
Electronic Publication 相似文献
19.
Jin-Soo Lee Kyung-Seok Ko Tong-Kwon Kim Jae Gon Kim Seong-Hyun Cho In-Suk Oh 《中国地球化学学报》2006,25(B08):152-152
The regional survey of groundwater used as a small water supply system was performed to know the effect of geology, soil properties and land use on groundwater quality at Nonsan City, Korea. A total of 126 groundwater samples were collected and analyzed at the study area. The multivariate statistical methods, principal components analysis and discriminant analysis, and GIS technique were used for the quantitative interpretation of groundwater quality. The study area is mainly composed of Precambrian gneiss, Jurassic granite, and Cretaceous volcanics, and metasedimentary rocks of the Ogcheon zone. The land use was grouped as paddy, upland, grassland, resident, point source, industrial area, and water system. The soil properties were classified as 4 major groups, Entisols, Alfisols, Inceptisols, and Ultisols, by the degree of development, and reclassified as 11 subgroups. The modified and simplified geologic map, soil map, and land use map were made by using ARCGIS soft-ware. The area of geology, soil property, and land use affecting the groundwater quality for each well were also calculated by ARCGIS soft-ware to acquire the quantitative parameters for multivariate statistical analysis. The monitoring results of groundwater in the study area showed that 13%-21% of the groundwater samples exceeded the portable water guideline and the main causes were turbidity, bacteria, arsenic and nitrate-N. The spatial distribution of each component showed the close relationship between groundwater quality and geology reflecting the topography, land use. 相似文献
20.
Land subsidence is common in some regions of China. Various eco-environmental problems have arisen due to changes in water–rock interactions in these subsided areas, for which a comprehensive understanding of the hydrogeological setting is needed. This paper presents the general status of land subsidence in three typical subsided areas of China through the compilation of relevant data, and reviews some typical changes in the water–rock interactions in subsided areas along with related eco-environmental issues. It is found that the subsidence development and distribution are controlled by the groundwater-withdrawal intensity externally, and by the thickness and compressibility of unconsolidated sediments internally. The physical changes and related effects of water–rock interactions in subsided areas include: (1) the decreased ground elevation that caused floods, waterlogged farmland, etc.; (2) the differential subsidence that caused ground fissures; and (3) the change of seepage field that caused substantial reduction of the water resource. Chemically, the changes and related effects of water–rock interactions include: (1) the change to the chemical environment or processes due to the hydrogeologic structure alteration, which caused groundwater pollution; and (2) hydrologic mixing (seawater intrusion, artificial recharge; exchange with adjacent aquifers or aquitards), which degraded the groundwater quality. Further research on the subsided areas in China is suggested to reveal the mechanisms regarding biological and gaseous (meteorological) changes from the perspective of interacting systems among water, rocks, biological agents and gases. 相似文献