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This article aims to explore the relationship between individual adaptive actions and enhancement of community resilience to climate change as a communal objective. It proposes to pay attention to the concept of reflexivity as the primary individual capacity to link adaptive actions and community resilience. Drawing on the field research conducted in northern Ghana in 2015, this article specifically examines life histories of four small farmers and shows that they individually take adaptive actions and reflect on these actions. However, little opportunity exists for them to systematically communicate the reflections with others to learn from their experiences, nurture collective agency and enhance community resilience. The article concludes by outlining new strategies needed to facilitate the communication in particular cultural and policy contexts.  相似文献   
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Food processing and consumption by herbivores are affected differently by the availability of forage quality and quantity per unit of time. This demonstrates the “Allometric response concept”, and it is considered a significant determinant in habitat use for foraging by grazers. The relevance of this approach has comprehensively been applied to herbivores of different body sizes, but little is known about its demonstration to explain patch use in herbivores with different digestive physiology and body size. We explain the use of patches by grazing herbivores of different digestive physiology and body sizes, Hippopotamus amphibius (hippopotamus, mega non-ruminant) and cattle (ruminant), by integrating foraging relationship herbivores. We analysed the significant relationships between species dropping densities and environmental variables across forty-eight 100 m×100 m plots in Bui National Park, Ghana, during the wet and dry seasons. We found that both species utilised areas closer to the river in the wet season, but the H. amphibius foraged further away from the river during the dry season. Sward height also determined patch use by both species, with the H. amphibius utilising shorter swards than the cattle. Considering the quality of food resources, the study revealed that patch selection of ruminants (cattle) was significantly influenced by nitrogen content. In contrast, acidic detergent fibre content was positively related to non-ruminant species (H. amphibius). The high seasonal effect of sward height and food quality on patch use is primarily due to the species digestive physiology and body size of hippopotamus and cattle at the Bui National Park.  相似文献   
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A preliminary assessment of toxic element pollution caused by artisanal and small-scale gold mining in the Bonsa river of Ghana as well as the influence of TOC and SO4 2? concentration on these traces in the sediment has been determined. With the exception of mercury (Hg), manganese (Mn), and arsenic (As), the concentration of aluminum (Al) in filtered river water exceeded the WHO guideline limit of 0.1 mg L?1 in drinking water. Analyses of toxic element in sediment using Canadian Sediment Quality Criteria, contamination factor, geoaccumulation index, and enrichment factor indicate that river sediment is severely contaminated with Hg confirming the negative impact of the amalgamation technique in gold beneficiation in Ghana. The level of Hg in the surface water exceeded reported values from some rivers in Africa, Asia, and South America. The ranking order of the mean element concentration in both matrices followed the conservative order of traces found in the Earth crust except copper, which was below the detection limit of 0.01 mg kg?1. A Pearson correlation matrix of the toxic element and geology of the river bedrock indicates that the Hg contamination is of anthropogenic origin whilst As, Mn, and Al are the result of natural enrichment. The partitioning of elements in the sediment compartments is independent of TOC and SO4 2? concentration. Health-risk assessment based on average daily dose, hazard quotient, and cancer risk indicates that Hg is a health risk to the human population. In conclusion, the study has shown that there is a likely anthropic affection of the river and that this situation has worsened since earlier studies. In order to sustain aquatic life and to prevent future human health hazard, an immediate mercury remediation in the river is recommended.  相似文献   
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