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361.
Bassett Imogen E. McNaughton Ellery J. Plank Gemma D. Stanley Margaret C. 《Environmental management》2020,66(1):30-41
Environmental Management - Cat ownership is increasing globally, representing a growing threat to urban wildlife. Although some cities have policies and strategies for managing owned cats, the... 相似文献
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Nitrate-nitrogen (NO?-N) loading to surface water bodies from subsurface drainage is an environmental concern in the midwestern United States. The objective of this study was to investigate the effect of various land covers on NO?-N loss through subsurface drainage. Land-cover treatments included (i) conventional corn ( L.) (C) and soybean [ (L.) Merr.] (S); (ii) winter rye ( L.) cover crop before corn (rC) and before soybean (rS); (iii) kura clover ( M. Bieb.) as a living mulch for corn (kC); and (iv) perennial forage of orchardgrass ( L.) mixed with clovers (PF). In spring, total N uptake by aboveground biomass of rye in rC, rye in rS, kura clover in kC, and grasses in PF were 14.2, 31.8, 87.0, and 46.3 kg N ha, respectively. Effect of land covers on subsurface drainage was not significant. The NO?-N loss was significantly lower for kC and PF than C and S treatments (p < 0.05); rye cover crop did not reduce NO?-N loss, but NO?-N concentration was significantly reduced in rC during March to June and in rS during July to November (p < 0.05). Moreover, the increase of soil NO?-N from early to late spring in rS was significantly lower than the S treatment (p < 0.05). This study suggests that kC and PF are effective in reducing NO?-N loss, but these systems could lead to concerns relative to grain yield loss and change in farming practices. Management strategies for kC need further study to achieve reasonable corn yield. The effectiveness of rye cover crop on NO-N loss reduction needs further investigation under conditions of different N rates, wider weather patterns, and fall tillage. 相似文献
364.
Penn CJ Vitale J Fine S Payne J Warren JG Zhang H Eastman M Herron SL 《Journal of environmental quality》2011,40(1):233-241
Transportation of poultry litter out of nutrient limited watersheds such as the Illinois River basin (eastern Oklahoma) is a logical solution for minimizing phosphorus (P) losses from soils to surface waters. Transportation costs are basedon mass of load and distance transported. This study investigated an alternative litter storage technique designed to promote carbon (C) degradation, thereby concentrating nutrients for the purpose of decreasing transportation costs through decreased mass. Poultry litter was stored in 0.90-Mg conical piles under semipermeable tarps and adjusted to 40% moisture content, tested with and without addition of alum (aluminum sulfate). additional study was conducted using 3.6-Mg piles under the same conditions, except tested with and without use of aeration pipes. Samples were analyzed before and after (8 wk) storage. Litter mass degradation (i.e., loss in mass due to organic matter decomposition) was estimated on the basis of changes in litter total P contents. Additional characterization included pH, total nutrients, moisture content, total C, and degree of humification. Litter storage significantly decreased litter mass (16 to 27%), concentrated nutrients such as P and potassium (K) and increased proportion of fulvic and humic acids. The addition of aeration pipes increased mass degradationrelative to piles without aeration pipes. Nitrogen volatilization losses were minimized with alum additions. Increases in P and K concentrations resulted in greater monetary value per unit mass compared with fresh litter. Such increases translate to increased litter shipping distance and cost savings of $17.2 million over 25 yr for litter movement out of eastern Oklahoma. 相似文献
365.
Understanding stewardship behaviour: factors facilitating and constraining private water well stewardship 总被引:1,自引:0,他引:1
Kreutzwiser R de Loë R Imgrund K Conboy MJ Simpson H Plummer R 《Journal of environmental management》2011,92(4):1104-1114
Regulatory frameworks to ensure municipal drinking water safety exist in most North American jurisdictions. However, similar protection is rarely provided to people reliant on water provided from private wells. In Canada, approximately 4 million people depend on privately owned, domestic wells for their drinking water. Numerous studies have shown that people who rely on private wells for their water supplies are at risk from nitrate and bacterial contamination. Given the fact that regulations relating to private wells tend to be weak or poorly enforced, actions taken by well owners to protect their own drinking water safety are extremely important. Drawing on one of the largest and most comprehensive surveys of private well owners ever conducted in Canada or elsewhere, this paper explores factors that influence well owner stewardship behaviour. Key behaviours examined included annual testing of well water and inspection of wells, measures to protect water quality, and proper decommissioning of unused wells. A geographically-stratified survey, sent to 4950 well owners in Ontario, Canada, resulted in an effective response rate of 34% (n = 1567). Logistic regression analyses revealed that motivations for well stewardship behaviours included reassurance, the perception of problems, and knowledge of the environment. Knowing how to perform stewardship behaviours was an important antecedent to action. Barriers to stewardship included complacency, inconvenience, ignorance, cost, and privacy concerns. To promote stewardship, local initiatives, better educational materials, and enforcement through real estate laws are all required. Ultimately, drinking water safety for people reliant on private wells is shown to be a responsibility shared by governments and private well owners. 相似文献
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Key Elements of Landscape Pattern Measures 总被引:9,自引:0,他引:9
369.
Hans Schreier Sandra Brown Margaret Schmidt Pravakar Shah Bubhan Shrestha Gopal Nakarmi Khagendra Subba Susanne Wymann 《Environmental management》1994,18(1):139-150
GIS overlay techniques were used to provide a quantitative historic documentation of deforestation and land-use dynamics in
the Middle Mountains of Nepal between 1947 and 1990. Deforestation was most critical in the 1960s, but active afforestation
programs in the 1980s have reversed the process. In spite of these trends, the degradation problem is more complex. The GIS
evaluation showed that 86% of the recently afforested land is now under pine plantations located primarily at lower elevations
and moderately steep slopes. In contrast, rainfed agricultural expansion is most pronounced on acidic soils and steeper, upper
elevation sites, suggesting marginalization of agriculture. Agricultural expansion coupled with major losses of grazing land
to pine forests are the key processes pointing towards major animal feed deficits. An alternative animal feed source is suggested
through GIS using a topographically based microclimatic classification to generate a tree-planting map where the optimum ecological
conditions for selective native fodder tree species are identified. 相似文献
370.
Conservation and the Social Sciences 总被引:16,自引:0,他引:16