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NGUYEN VAN DE IAN DOUGLAS JULIA MCMORROW SARAH LINDLEY DAO KIM NGUYEN THUY BINH TRAN THI VAN LE HUU THANH NGUYEN THO 《Geographical Research》2008,46(1):4-16
To help improve the well‐being of the local people, a joint Vietnamese‐UK team set out to establish a way of estimating soil and nutrient losses under different land management scenarios, using field data extrapolated through remote sensing and GIS, to obtain catchment‐wide estimates of the impact of land cover change. Immigration from remote provinces to the Dong Phu District of Binh Phuóc Province, about 120 km north of Ho Chi Minh City, has led to disruption of soil surface stability on easily eroded clayey sandstones, creating rapid nutrient depletion that affects crop yields and siltation in the channel of the Rach Rat river downstream. The poor farmers of the areas see crop yields drop dramatically after two or three years of cultivation due to the fertility decline. Soil loss varies dramatically between wet season and dry season and with ground cover. Erosion bridge measurements showed a mean loss of 85.2 t ha?1 y?1 under cassava saplings with cashew nuts, 43.3 t ha?1 y?1 on uncultivated land and 41.7 t ha?1 y?1 under mature cassava. The rates of erosion were higher than those reported in many other parts of Vietnam, reflecting the high erodibility of the friable sandy soils on the steep side‐slopes of the Rach Rat catchment. However, although the actual measurements provide better soil loss data than estimates based on the parameters of soil loss equations, a large number of measurement sites is needed to provide adequate coverage of the crop and slope combinations in this dissected terrain for good prediction using GIS and remote sensing. 相似文献
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《Eurasian Geography and Economics》2013,54(2):285-299
Two EU-based senior economists analyze the contribution of bank liquidity creation to the Russian economy, as well as changes in creation of liquidity occurring during the global financial crisis. Applying the methodology of Berger and Bouwman's (2009) study of U.S. banking to a rich panel dataset for Russian banks for the period 1999-2009, the authors compute three alternative measures of bank liquidity creation. They find evidence of increased creation of liquidity in real terms over the period and also determine that state-controlled (versus private) banks and Russia's largest banks (versus intermediate-size and small banks) contributed most to liquidity creation (lower in Russia than in the U.S.). Their findings suggest that consolidation of the Russian banking sector may prove more instrumental in increasing liquidity creation than privatization per se. 相似文献
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The Spraberry Formation in west‐central Texas is a highly fractured formation with both extension and shear fractures. At least two sets of natural fractures exist in two reservoir intervals. We have considered two possible origins for the fracturing: (i) high fluid pressure plus tectonic stress and (ii) tectonic stress at near‐hydrostatic fluid pressure. Reconstruction of geologic, thermal and hydrodynamic histories suggests that high fluid pressures probably did not occur during the basin’s history. To explore the second hypothesis, we developed and applied a calibrated, discrete‐element model of Spraberry strata to investigate whether weak Laramide compressional forces could cause fractures in the absence of high fluid pressures. Simulation results suggest that a mild compressional episode of geologically short duration may indeed have induced conjugate shear fractures. 相似文献
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Until recently the objectives of tropical river management were narrowly construed: the development imperative drove resource policy. During recent decades, community attitudes to river and water management have changed considerably and the national program of water reform, the National Water Initiative, is accelerating alterations to the way that water is used, managed and priced. A broader range of values and imperatives is now influencing water resource management policy. Not least is the concern over the ecological impacts and economic inefficiencies of the large‐scale hydrological schemes that once excited the public's imagination. This paper reports on a recent study of social and economic values of tropical rivers conducted by the authors for an Australian statutory research and development corporation. The study shows that the values associated with tropical rivers have changed and diversified over time with growing societal awareness of the contribution made by unregulated, healthy river systems to human wellbeing and cultural identity. As a consequence of substantial social change, tropical river management must now contend with a more complex array of societal values and water management objectives. 相似文献
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Samples of ancient Indian lime plaster have not previously been analysed. Excavation of a seventh century AD baked brick structure provided the necessary samples for a detailed laboratory examination of plaster. The plaster samples were studied by chemical and petrographic methods. The probable sources of lime and sand were indicated by the mineralogy. 相似文献
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JULIAN SEDDON ANDREW BATHGATE SUE BRIGGS MICAH DAVIES STUART DOYLE MICHAEL DRIELSMA ANDRE ZERGER PHIL GIBBONS RON HACKER 《Geographical Research》2011,49(2):132-152
The need for public investment to address loss of biodiversity in agricultural landscapes is well recognised, yet there is little analysis of the likely benefits of land‐use change for regional biodiversity or the cost effectiveness of different investment options. We estimated benefits for biodiversity and cost effectiveness of different investment scenarios over 50 years for a farming area in south‐eastern Australia. Declines in biodiversity were predicted under status quo land use. Implementing actions in the investment scenarios improved biodiversity status only slightly, compared with status quo land use. Future biodiversity status differed little between biodiversity‐focused investment and salinity‐focused investment. Biodiversity status equalled or exceeded current status only for investment scenarios with much more extensive revegetation than in catchment targets. Cost effectiveness of biodiversity improvement varied greatly between investment strategies. Biodiversity improvement was more cost effective when investment to meet catchment targets was focused on revegetation for salinity management rather than on high conservation value areas, because of lower opportunity costs for salinity management. With enhanced investment, the cost effectiveness of biodiversity improvement was greater when actions were in high conservation areas. Although improvements in biodiversity were small under the changed farming system scenarios, their cost effectiveness was higher than the other investment scenarios. Regional scale improvements in biodiversity in farming areas will require increased stewardship payments or other economic incentives for landholders. 相似文献
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Soils in a lower Hunter valley vineyard, New South Wales, Australia, were sampled and analysed for caesium‐137, an indicator of soil erosion status, in 1984–1985 and 2004. From the time of the vineyard's first establishment in 1971 to 1985, estimated soil losses were 250 tonnes (equivalent to 64.2 t ha?1 yr?1). Re‐sampling in 2004 showed that soil losses were 48 tonnes in the 19 years since 1985, equivalent to 9.7 t ha?1 yr?1. The decline in erosion rates may be explained by a change in land and soil management from intensive cultivation to one of no cultivation (sod culture) in 1998, and a lower annual rainfall and fewer rain‐days per year in the period from 1986 to 2004. 相似文献
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Assessing the impact of prehistoric sites on their local environment is difficult to accomplish with standard archaeological methods. Simulation modeling offers a solution to this issue, but it is first necessary to delimit a site catchment, or “zone of impact”, around archaeological sites in which to carry out human–environment interaction modeling. To that end, I have developed a new method for GIS-based catchment reconstruction and distilled it into a custom module (r.catchment) for GRASS GIS, which calculates catchments of a given area based on anisotropic travel costs from a point of origin. One method of applying this new module in exploratory catchment modeling is discussed using the pastoral economy of the Late Neolithic period in Wadi Ziqlâb, Northern Jordan as a test case. A model of Late Neolithic herding economy and ecology is constructed, which combines data from archaeology, phytogeography, range science, agronomy, and ethnohistory. Four sizes of pastoral catchments are then derived using r.catchment, and the herd ecology model is used to estimate the stocking-rate (carrying capacity) of mixed goat and sheep herds for each catchment. The human populations these herd numbers could support (between 3 and 630 people in the Wadi) are then compared with human population estimates derived from household architectural analyses (between 18 and 54 people in the Wadi) to determine the most probable catchment configurations. The results indicate that the most probable zone of impact around the known Late Neolithic sites in Wadi Ziqlâb was somewhere between 9 and 20 square kilometers, delineated by 3 and 4.5 km pasture radii respectively. 相似文献
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运用Arc GIS平均最近邻、核密度估计和波段集统计等方法,考察长春市中心城区银行网点空间特征和规律,以及银行网点与人口和主要经济活动的空间关系,发现:①银行网点呈明显集聚分布特征,这种集聚主要分布于商业和商务中心及新建中高档住宅小区密集地段;②银行网点核密度与其到CBD距离呈负相关,并随距离地增加呈对数衰减;③银行网点密度与人口-经济活动密度在街道甚至更小空间尺度上存在较显著的正相关;④银行网点核密度与大型商业网点和主要写字楼核密度均呈较强正相关,而与大型制造业企业核密度几乎不存在相关性,说明商业和楼宇经济空间特征对城市内部银行网点布局具有深刻影响,而制造业的微观区位对银行网点布局几乎无影响。 相似文献
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Stephen E Darby Colin R Thorne† 《Transactions (Institute of British Geographers : 1965)》2000,25(1):91-107
Landowners along the Missouri River in Montana believe that the operation of Fort Peck Dam has initiated bank erosion, thus threatening agricultural development within the region. Their concerns have been heightened by proposals to increase discharge in order to enhance fisheries and wildlife interests. Geomorphological evaluation indicates that bed degradation and bank erosion have declined since construction of the dam, and the channel is now approaching dynamic equilibrium; public sensitivity to the proposed change is greater than the morphological sensitivity of the river. Sustainable management of the Missouri is now based on strategies that place more emphasis on partnership with local citizens. 相似文献
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分区是考古学研究常用的方法,在历史考古学研究中,因文献记载的详细、考古材料的连续、集中,使具体地点的考古学分区研究有了进一步细化的可能。安徽马鞍山地区吴晋墓葬在孙吴和东晋两个时期有着显著的区域特征,这与该地特殊的区位有着很大的关联,而这些规律的总结正体现出汉晋变迁考古学研究的地域意义,从而对历史考古学研究的方法进行有意探讨。 相似文献
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Kieran Westley 《The Journal of Island and Coastal Archaeology》2019,14(2):226-246
Increasing evidence indicates that ongoing and future climate change impacts, such as enhanced coastal erosion driven by intensified storms and sea-level rise, will be destructive or problematic for coastal archaeological heritage. Approaches to this problem range from broad-scale GIS-based vulnerability assessments to site-scale monitoring and survey. In all cases, the approach chosen should be based on the best-available data on the local historic environment and pattern of coastal change. Therefore, this paper will demonstrate how such data can be successively acquired and enhanced using an integrated approach that builds on and refines a previously conducted broad-scale vulnerability assessment. This approach was adopted in the study region (Northern Ireland) owing to a lack of coherent and up-to-date information on shoreline change. This approach incorporated the GIS-based Digital Shoreline Analysis System (DSAS) to quantify and analyze local shoreline change. DSAS is a software extension for ESRI ArcGIS which allows calculation of rate-of-change statistics using past shorelines identified from georeferenced historic maps and vertical aerial imagery. Additionally, a field survey was conducted to assess the condition of recorded sites, and identify unrecorded ones. Results revealed a more complex pattern of shoreline change in the study area (Magilligan Foreland, Lough Foyle) than previously anticipated, with zones of significant erosion interspersed with areas of stability or advance. Fifty-one new sites ranging from the prehistoric period to the Second World War were also identified. The new information was used to develop a priority classification based on site significance, condition and risk level which improved significantly on the uniform classification of the original broad-scale assessment. 相似文献
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Despite being a major site of recent population growth and, arguably, a key arena for sustainability concerns, the rural‐urban fringe has received relatively little attention in the literature concerning Australian cities and urban policy. To address this shortcoming the authors review post‐World War II efforts to plan the rural‐urban fringes of Sydney and Adelaide and find a number of issues for contemporary policy‐makers. First, the fringe is becoming increasingly complex due to multi‐faceted demographic change, a broadening economic base and demands for better environmental management, all within the context of an evolving understanding of sustainability. Second, water resource management, partly under the auspices of integrated natural resource management, is assuming a much higher priority than in early fringe planning endeavours, which emphasised urban containment, agricultural land protection and landscape conservation. Third, and partly as a consequence of this shift of priorities, there is also evidence of changes to the nature and focus of policy tools used in the fringe, with land management concerns now cutting across traditional land use planning. Finally, and fundamentally, these observations raise questions about how future governance of the fringe should be organised. Together these four themes pose an enthralling series of challenges for policy‐makers for which much more research and discussion are needed. 相似文献
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国际酒店人力资源管理研究述评——主题与趋势的引文分析 总被引:1,自引:0,他引:1
本文运用基于Histcite软件的引文分析方法和基于Citespace软件的共被引分析方法,系统梳理了近20年发表在6本旅游及接待业著名期刊上酒店人力资源管理的相关文献.研究结果显示,引文分析有助于厘清研究主题的演进关系,而共被引分析有助于识别研究前沿和研究热点,并讨论了酒店人力资源领域研究成果的实际应用价值. 相似文献
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The contemporary trend within natural resource governance sees a strong increase in collaborative management. A successful turnout of these arrangements is, however, dependent upon the formation and characteristics of advocacy coalitions. Uncovering the rationale determining coalitions is therefore a key undertaking in policy analysis and the advocacy coalition framework (ACF) has been widely applied for this purpose. This article aspires to test several important hypotheses regarding the nature of coordination networks and the formation of coalitions, treating the ACF both as an inspiration and as a framework in need of further refinement. This is done in the context of a complex and conflict‐ridden policy subsystem: the Swedish carnivore‐management subsystem. The results indicate, firstly, that perceived belief correspondence, and not perceived influence, is the driving mechanism behind coordination; and, secondly, that the catalog of beliefs shared by actors within a coalition is composed by policy core beliefs, in particular, with a more normative content, while no connection between deep core beliefs and coordination is found. 相似文献
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From the modern to the archaeological: starch grains from millets and their wild relatives in China 总被引:1,自引:0,他引:1
Xiaoyan Yang Jianping ZhangLinda Perry Zhikun Ma Zhiwei Wan Mingqi LiXianmin Diao Houyuan Lu 《Journal of archaeological science》2012,39(2):247-254
Starch grains from 31 modern samples of millets derived from the seeds of 7 species within the genus Setaria and 2 species within the genus Panicum were analyzed to determine diagnostic morphological characteristics. Ancient starch grains recovered from a sample of broomcorn millet (Panicum miliaceum) excavated from the Cishan site (10.0-7.6 cal yr BP) in the North China Plain were then subjected to the same analyses to determine the differences in morphologies, if any, between modern and ancient samples. The data indicate that morphological features, and particularly surface and fissure features, will allow for solid identifications of ancient millet starches, while size classes will be helpful, but will not be dependable taxonomic indicators. 相似文献