To Move or not to Move: Community Members’ Reaction to Surface Mining Activities in the Upper West Region of Ghana     

Roger Antabe  Kilian N. Atuoye  Vincent Z. Kuuire  Yujiro Sano  Godwin Arku  Isaac Luginaah 《社会与自然资源》2020,33(3):368-385

Abstract

Despite the impact of mining-induced environmental change on community livability, we know little about how disparities in knowledge of health risks associated with mining influence residents’ response, especially in an already environmentally stressed context. Guided by theoretical insights from solastalgia, we examined residents’ decision to relocate due to increasing gold mining activities in the fragile Northern Savannah Ecological Zone of Ghana. Fitting complementary log-log regression models to cross-sectional data from the Upper West Region (UWR) of Ghana, we found that residents with limited knowledge of potential health impacts of mining and those who believe mining activities were not meeting environmental standards were more likely to consider relocating. Given the centrality of land in community health and wellbeing in the UWR, Ghana’s mining guidelines should promote local participation in the regulation of mining activities and guarantee the rights of indigenes to livable native lands.  相似文献   

Water sensor network applications: Time to move beyond the technical?          下载免费PDF全文

Feng Mao  Julian Clark  Wouter Buytaert  Stefan Krause  David M. Hannah 《水文研究》2018,32(16):2612-2615

  相似文献   

Clustering circulation in eastern Asia as a tool for exploring possible mechanisms of extreme events and sources of model error     

Clark  Robin T.  Zhang  Lixia  Li  Chaofan 《Climate Dynamics》2021,56(11):4091-4108

Every summer in eastern Asia, the combined effects of complex topography, multiple potential moisture sources and a mixture of sub-tropical and mid-latitude dynamics produces an environment, in which subtle differences in spatial patterns of atmospheric circulation can profoundly affect the geographic distribution of rainfall. Understanding and quantifying these patterns is a fundamental requirement if we are to understand, predict or project rainfall events likely to cause impacts to society in the region. To help the scientific community with this task, a method is presented here, in which spatial patterns of summer sea level pressure over eastern Asia are clustered into a set of eight circulation types, with examples given of their potential use. We find that the within-season prevalence of individual circulation types exhibit a strong relationship with the seasonal progression of the summer monsoon whilst providing a spatially coherent, physical interpretation of the monsoon for all parts of eastern Asia. Beyond this, the clustering approach permits the attribution of notable rainfall anomalies in almost any location within the domain used to build the clusters. Examples are given, showing how circulation specific moisture transport anomalies in one part of China can result in anomalously dry days in another part of the country. Two further applications of the clustering approach are demonstrated using climate simulations. The first is of circulation specific model errors which can allow targeted model development. The second provides information about anomalies which are plausible, but have yet to be observed, possibly due to limitations in the observed record.

  相似文献   

Eolian Transport of Geogenic Hexavalent Chromium to Ground Water     

by Warren W. Wood  David Clark  Jeffrey L. Imes  Terry B. Councell 《Ground water》2010,48(1):19-29

A conceptual model of eolian transport is proposed to address the widely distributed, high concentrations of hexavalent chromium (Cr⁺⁶) observed in ground water in the Emirate of Abu Dhabi, United Arab Emirates. Concentrations (30 to more than 1000 μg/L Cr⁺⁶) extend over thousands of square kilometers of ground water systems. It is hypothesized that the Cr is derived from weathering of chromium-rich pyroxenes and olivines present in ophiolite sequence of the adjacent Oman (Hajar) Mountains. Cr⁺³ in the minerals is oxidized to Cr⁺⁶ by reduction of manganese and is subsequently sorbed on iron and manganese oxide coatings of particles. When the surfaces of these particles are abraded in this arid environment, they release fine, micrometer-sized, coated particles that are easily transported over large distances by wind and subsequently deposited on the surface. During ground water recharge events, the readily soluble Cr⁺⁶ is mobilized by rain water and transported by advective flow into the underlying aquifer. Chromium analyses of ground water, rain, dust, and surface (soil) deposits are consistent with this model, as are electron probe analyses of clasts derived from the eroding Oman ophiolite sequence. Ground water recharge flux is proposed to exercise some control over Cr⁺⁶ concentration in the aquifer.  相似文献   

A multidimensional streamline-based method to simulate reactive solute transport in heterogeneous porous media     

Paulo A. Herrera  Albert J. Valocchi  Roger D. Beckie 《Advances in water resources》2010

We present a new streamline-based numerical method for simulating reactive solute transport in porous media. The key innovation of the method is that both longitudinal and transverse dispersion are incorporated accurately without numerical dispersion. Dispersion is approximated in a flow-oriented grid using a combination of a one-dimensional finite difference scheme and a meshless approximation. In contrast to previous hybrid alternatives to incorporate dispersion in streamline-based simulations, the proposed scheme does not require a grid and, hence, it does not introduce numerical dispersion. In addition, the proposed scheme eliminates numerical oscillations and negative concentration values even when the dispersion tensor includes the off-diagonal coefficients and the flow field is non-uniform. We demonstrate that for a set of two- and three-dimensional benchmark problems, the new proposed streamline-based formulation compares favorably to two state of the art finite volume and hybrid Eulerian–Lagrangian solvers.  相似文献   

Practical Use of Computationally Frugal Model Analysis Methods          下载免费PDF全文

Mary C. Hill  Dmitri Kavetski  Martyn Clark  Ming Ye  Mazdak Arabi  Dan Lu  Laura Foglia  Steffen Mehl 《Ground water》2016,54(2):159-170

Three challenges compromise the utility of mathematical models of groundwater and other environmental systems: (1) a dizzying array of model analysis methods and metrics make it difficult to compare evaluations of model adequacy, sensitivity, and uncertainty; (2) the high computational demands of many popular model analysis methods (requiring 1000's, 10,000 s, or more model runs) make them difficult to apply to complex models; and (3) many models are plagued by unrealistic nonlinearities arising from the numerical model formulation and implementation. This study proposes a strategy to address these challenges through a careful combination of model analysis and implementation methods. In this strategy, computationally frugal model analysis methods (often requiring a few dozen parallelizable model runs) play a major role, and computationally demanding methods are used for problems where (relatively) inexpensive diagnostics suggest the frugal methods are unreliable. We also argue in favor of detecting and, where possible, eliminating unrealistic model nonlinearities—this increases the realism of the model itself and facilitates the application of frugal methods. Literature examples are used to demonstrate the use of frugal methods and associated diagnostics. We suggest that the strategy proposed in this paper would allow the environmental sciences community to achieve greater transparency and falsifiability of environmental models, and obtain greater scientific insight from ongoing and future modeling efforts.  相似文献   

美国俄亥俄州橡树-山毛榉混交林森林碳储量研究     

陶玉华  Roger A. WILLIAMS 《资源与生态学报(英文版)》2013,4(2):115-124

本研究量化了美国俄亥俄州橡树-山毛榉混交林森林碳储量,研究结果表明森林碳密度的增长率与其商品材积和总材积的增长率是一致的。橡树-山毛榉混交林连年增长量（CAI）和年平均增长量（MAI）高峰值分别出现在第23和46年。对于地上碳储量而言,其CAI和MAI最高值分别出现在第26年和53年。对于地上碳密度和地上商品材碳密度,其MAI高峰出现在第30年,与其同时间内总蓄积量和商品材的蓄积量出现的情况一致。了解了森林碳储量的增长和蓄积量的增加模式是相近的道理,有助于我们理解森林蓄积量增长的管理模式过渡到森林碳储量管理的模式。  相似文献   

Quantifying the relative intensity of fishing on New Zealand seamounts     

Richard L. O'Driscoll  Malcolm R. Clark 《新西兰海洋与淡水研究杂志》2013,47(4):839-850

New Zealand seamounts support major fisheries for several deepwater fish species, including orange roughy (Hoplostethus atlanticus) and smooth oreo (Pseudocyttus maculatus). Although a high proportion of features in the depth range 500–1000 m have been fished, very little is known about the ecological impacts of bottom trawling on seamounts. The potential impact is likely to be influenced by the spatial extent and frequency of fishing. A new index is presented to assess the relative intensity of trawling on New Zealand seamounts. The fishing effects index (FEI) incorporates information on the density of fishing on the seamount as a proportion of the seabed area and also on tow direction. Detailed fisheries data from more than 250 000 tows were examined to calculate FEI for New Zealand seamounts. The most intensively fished seamounts were on the south Chatham Rise, an area characterised by a large number of relatively small features which were fished serially for orange roughy in the 1980s and 1990s. Other seamounts with high FEI were on the north Chatham Rise, Challenger Plateau, and off the east coast of the North Island. A range of sensitivity analyses indicated that the general rankings of seamounts were relatively robust to the choice of arbitrary thresholds used to assign tows to seamounts.  相似文献   

A numerical model investigation of the residual circulation in Hauraki Gulf,New Zealand     

Roger Proctor  Malcolm J.N. Greig 《新西兰海洋与淡水研究杂志》2013,47(3):421-442

The homogeneous residual circulation in Hauraki Gulf arising from the tides, steady winds, and oceanic inflows is considered by use of a depth‐averaged 2‐dimensional numerical model. Vertical current structure of the wind‐driven circulation is derived by using the computed wind‐induced sea surface slopes, the wind stress, and a prescribed vertical eddy viscosity. Tidal residual circulation is weak, less than 0.01 ms^‐1 over most of the Gulf. The response of the Gulf to wind‐forcing indicates a preference for north‐west/south‐east directed winds, the flow through the Gulf being more than 3 times as strong as for winds from other directions. Surface currents are mainly in the wind direction, but subsurface currents reveal closed circulation cells in near‐coastal areas. Simple oceanic inflows give rise to water movements which penetrate to the inner part of the Gulf.  相似文献   

Alluvial floodplain classification by multivariate clustering and discriminant analysis for low‐relief glacially conditioned river catchments          下载免费PDF全文

Roger T. J. Phillips  Joseph R. Desloges 《地球表面变化过程与地形》2015,40(6):756-770

River classifications provide useful frameworks to understand complex fluvial landscapes and to manage freshwater ecosystems. Alluvial floodplains for rivers in low‐relief glacially conditioned catchments of southern Ontario (Canada) are classified and tested using a sequence of multivariate statistical analyses. An original dataset of 109 floodplain sites is investigated using k‐means clustering, principal component analysis, and discriminant analysis statistical approaches. Four primary floodplain types are proposed representing basic morphological, stratigraphical, and sedimentological characteristics. Classifications are successfully discriminated by two principal dimensions: (1) stream power‐resistance; and (2) floodplain sedimentology. The latter is most efficiently represented by the availability of alluvial sand, and specifically a new variable defined as floodplain sand equivalent (FSE). Floodplain types are generally consistent with previous river classifications, however the glacial legacy requires refined classifications which account for inherited cobble bed materials and patterns of sand supply. Representing the residual variability of stream power‐resistance correlations, a third explanatory dimension of sediment transport is suggested, and may explain some within‐class variability in channel morphology. Balancing the opposing concepts of fluvial process domains and landform continuums, the potential for transitional floodplain types is also explored. The proposed first‐order alluvial floodplain classifications provide a basis from which to further investigate geomorphological diversity within the context of complex glacial legacy effects in low‐relief settings. Future research to reveal the spatial arrangement and linkages of distinct morphological groups within a regional landscape mosaic is expected to provide insights into patterns of post‐glacial fluvial adjustment. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献