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森林大火潜在危险和可燃物干旱度研究 总被引:3,自引:0,他引:3
介绍了森林大火潜在危险的可燃物干旱度指标研究,以及干旱度指数SDI的计算方法,同时对干旱度指数进行了划分确定,以便在森林大火预报中作参考使用。 相似文献
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2004年1月1日生效的《工伤保险条例》规定了非法用工单位向伤亡人员赔偿的标准和争议解决的程序,但是非法用工单位不属于法律上合法的主体,劳动仲裁机关和法院不能对不存在的主体作出裁定和判决,就算作出裁判,也不可能得到执行,从而使得该条例规定的对非法用工单位伤亡人员的赔偿成为一纸空文。为此,笔者从劳动争议和诉讼主体认定,程序保障和伤亡人员及时得到救助三个方面提出建议,以确保条例得到执行。 相似文献
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VanWoert ND Rowe DB Andresen JA Rugh CL Fernandez RT Xiao L 《Journal of environmental quality》2005,34(3):1036-1044
Urban areas generate considerably more stormwater runoff than natural areas of the same size due to a greater percentage of impervious surfaces that impede water infiltration. Roof surfaces account for a large portion of this impervious cover. Establishing vegetation on rooftops, known as green roofs, is one method of recovering lost green space that can aid in mitigating stormwater runoff. Two studies were performed using several roof platforms to quantify the effects of various treatments on stormwater retention. The first study used three different roof surface treatments to quantify differences in stormwater retention of a standard commercial roof with gravel ballast, an extensive green roof system without vegetation, and a typical extensive green roof with vegetation. Overall, mean percent rainfall retention ranged from 48.7% (gravel) to 82.8% (vegetated). The second study tested the influence of roof slope (2 and 6.5%) and green roof media depth (2.5, 4.0, and 6.0 cm) on stormwater retention. For all combined rain events, platforms at 2% slope with a 4-cm media depth had the greatest mean retention, 87%, although the difference from the other treatments was minimal. The combination of reduced slope and deeper media clearly reduced the total quantity of runoff. For both studies, vegetated green roof systems not only reduced the amount of stormwater runoff, they also extended its duration over a period of time beyond the actual rain event. 相似文献
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Kholaif Moustafa Mohamed Nazief Haggag Kotb Xiao Ming 《Environmental science and pollution research international》2023,30(6):14365-14384
Environmental Science and Pollution Research - This study examines the relationship between uncertainty-fear toward COVID-19, green supply chain management (GSCM), and perceived service quality... 相似文献
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Study on phosphorus loadings in ten natural and agricultural watersheds in subtropical region of China 总被引:3,自引:0,他引:3
Yuyuan Li Cen Meng Ru Gao Wen Yang Junxia Jiao Yong Li Yi Wang Jinshui Wu 《Environmental monitoring and assessment》2014,186(5):2717-2727
Water eutrophication in subtropical regions of southern China threatens watershed health and is of major concern. However, annual phosphorus (P) loading and its dominant causes are still unclear, especially at the watershed scale. In this study, we investigated dynamic P loadings and associated factors (e.g., land use, livestock production, and runoff depth) in ten watersheds that varied in area from 9 to 5,212 ha in a hilly area of Hunan Province, China. A flowmeter was installed at the outlet of each watershed, and total P (TP) and soluble P (SP) concentrations were monitored periodically from June 2010 to October 2012. The results showed that annual P loadings (APLs) in the ten watersheds ranged from 22.8 to 247.8 kg P/km2 and that P loss primarily occurred from April to June of each year during the main rainfall season in the study area. In addition, the average eutrophication (>0.05 mg P/L) ratio for stream waters was 86.7 % during the study period, which was indicative of a potentially serious condition for the local water environments. Annual P loadings were linearly related to livestock density (LD; R?=?0.92, p?<?0.01), whereas the eutrophication ratio of stream water was significantly (p?<?0.05) correlated with LD (R?=?0.61), percentage cropland (R?=?0.71), and percentage forest cover (R?=??0.68). Thus, it is concluded that the control of livestock production has the greatest potential for reducing P loadings in watersheds in this subtropical area. This will be beneficial to the amelioration and protection of local environment. 相似文献