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211.
分析了湖南省区域投资环境条件,提出了优化投资环境思路:按点轴模式优化湖南区域经济空间布局结构,确立重点投资环境建设轴线;优化产业结构,优先对第二产业和优势产业进行投资环境建设;把人文环境和物质环境结合起来,着力改善区域经济发展的软、硬环境.  相似文献   
212.
Cameron Highlands is a mountainous region with steep slopes. Gradients exceeding 20 are common. The climate is favourable to the cultivation of tea, sub-tropical vegetables and flowers (under rain-shelter). Crop production is sustained by high fertiliser and manure applications. However, agriculture in this environment is characterised by high levels of soil erosion and environmental pollution. A study on the sustainability of these agro-ecosystems was conducted. Results indicated that soil loss was in the range of 24–42 ton/ha/yr under vegetables and 1.3 ton under rain-shelter. Sediment load in the vegetable sub-catchment reached 3.5 g/L, 50 times higher than that associated with flowers under rain-shelter and tea. The sediments contained high nutrient loads of up to 470 kg N/ha/yr. The N, P and K lost in runoff from cabbage farms was 154 kg/season/ha, whereas in chrysanthemum farms it was 5 kg. In cabbage farms, the N, P, and K lost through leaching was 193 kg/season/ha. The NO3–N concentration in the runoff from the cabbage farms reached 25 ppm but less than 10 ppm in runoff from rain-shelters. Inorganic pollution in the rivers was within the acceptable limit of 10 ppm. The sustainability of the agro-ecosystems is in the order of tea { > } rain–shelter ≫ vegetables.  相似文献   
213.
发展旅游对海岛环境的影响及应对策略研究   总被引:3,自引:0,他引:3  
孔海燕 《四川环境》2005,24(3):22-24
海岛作为一个独特的地理单元,旅游资源丰富,发展前景广阔,但在海岛旅游迅速发展的同时,海岛环境也受到极大的影响。而海岛又是环境敏感地区,生态环境脆弱,一旦破坏就难以恢复,所以重视海岛旅游出现的环境问题,加强对海岛环境的保护,促进海岛经济的可持续发展应引起广泛的关注和重视。  相似文献   
214.
为识别公众风险感知的演化规律和官方媒体参与的作用机制,首先,根据公众的行为表现划分不同风险感知群体,并分析群体间的相互竞争和官方媒体的扰动作用;然后,通过扩展Lotka Volterra模型建立群体间的相互竞争模型;在此基础上,通过推导模型平衡点及其稳定性分析模型演化规律;最后,运用数值仿真考查了官方媒体的参与对模型演化的影响。研究结果表明:模型演化具有3种结果情景,官方媒体参与能够显著改变模型演化的速度和结果。  相似文献   
215.
缪尔康 《四川环境》2014,(1):128-132
利用自动连续监测仪器对在成都市城区选定的监测点位开展了持续数日的测量,获取了测点的长时间监测数据,通过对监测数据的分析,研究了0.1~3000MHz射频电磁环境随时间变化的规律及其与人群作息时间的关系,并对电磁环境人工手动监测的适宜时间段进行了分析。  相似文献   
216.
Protected areas (PAs) and payments for ecosystem services (PES) are the top two mechanisms available for countries to achieve international REDD agreements, yet there are few empirical comparisons of their effects. We estimate the impacts of PAs and PES on forest conservation, poverty reduction, and population change at the locality level in Mexico in the 2000s. Both policies conserved forest, generating an approximately 20–25% reduction in expected forest cover loss. PES created statistically significant but small poverty alleviation while PAs had overall neutral impacts on livelihoods. Estimates by individual policy type for the same level of deforestation risk indicate that biosphere reserves and PES balanced conservation and livelihood goals better than strict protected areas or mixed-use areas. This suggests that both direct and incentive-based instruments can be effective, and that policies combining sustainable financing, flexible zoning, and recognition of local economic goals are more likely to achieve conservation without harming livelihoods.  相似文献   
217.
本文主要针对大气环境中PM2.5展开深入研究和论述,先介绍了大气环境中PM2.5的定义和危害,然后结合重量法、光散射法以及β射线吸收法等,对PM2.5的检测技术进行了深入分析,最后提出了几点治理措施,比如加大法治建设和政府监管力度、降低机动车尾气排放、控制工业废气排放、增加植被、加强区域联防联控机制的构建等,以对大气环境中PM2.5含量进行合理化控制,并将空气污染指数保持在可控范围内,避免大气环境污染问题的出现。  相似文献   
218.
The growing industrial interest in adopting sustainability programmes has ushered in studies regarding sustainability indicators which have continually flourished in current literature. However, limited attention is given to the development of priority ranking, which is an important input for any adopting firm. This paper presents a hybrid multi-criteria approach in determining priority areas in sustainable manufacturing (SM). Using fuzzy analytic hierarchy process to address uncertainty in hierarchical decision-making, this paper determines SM priority strategies and eventually identifies even lower level strategies. The computed sustainable manufacturing index is presented at both the organizational and operational levels for a real case study of an industrial plastic manufacturing firm. This work provides a detailed and transparent hierarchical decision-making approach based on SM framework, the use of which could be valuable to practicing managers across industries in their pursuit of greater sustainability.  相似文献   
219.
Nitrogen evolution was studied during the co-combustion of hydrothermally treated municipal solid wastes (HT MSW) and coal in a bubbling fluidized bed (BFB). HT MSW blending ratios as 10%, 20% and 30% (wt.%) were selected and tested at 700, 800, 900 °C. Emissions of NO and N2O from blends were measured and compared with the results of mono-combustion trials. Moreover, concentrations of precursors like NH3 and HCN were also quantified. The results are summarized as follows: NO emissions were predominant in all the cases, which rose with increasing temperature. The blending of HT MSW contributed to the NO reduction. N2O emissions decreased with temperature rising and the blending of HT MSW also presented positive effects. At 30% HT MSW addition, both NO and N2O emissions showed the lowest values (391.85 ppm and 55.33 ppm, respectively at 900 °C). For the precursors, more HCN was detected than NH3 and both played important roles on the gas side nitrogen evolution.  相似文献   
220.
为研究昌黎生态监控区夏季浮游植物群落结构特征及其与环境因子关系,采用2005~2013年夏季(8月)昌黎生态监控区海域浮游植物及环境因子的监测资料,基于Arc GIS 10.0和Canoco软件平台,运用典范对应分析方法,对浮游植物群落结构进行分析.结果表明,近9 a共鉴定出浮游植物3门23科39属105种,其中,硅藻门16科32属90种,占浮游植物总数的85.7%;甲藻门共6科6属14种,占总种类数的13.3%;金藻门1种.各年的优势种存在很大差异,按照优势度Y值的大小包括辐射圆筛藻(Coscinodiscus radiatus)、柔弱角毛藻(Coscinodiscus debilis)、笔尖根管藻(Rhizosolenia styliformis)、柏氏角管藻(Cerataulina bergoni)、威氏圆筛藻(Coscinodiscus wailesii)、海链藻(Thalassiosira sp.)、三角角藻(Ceratium tripos)、洛氏角毛藻(Coscinodiscus wailesii)、中肋骨条藻(Ceratium tripos)等.夏季细胞丰度年际变化较大,呈现逐渐降低的趋势.浮游植物的多样性指数H'值介于0.015~3.889,均匀度指数J值介于0.009~1,年际变化幅度较小;各站位间物种分布不均匀,优势种较少且优势度较大.对浮游植物群落与环境因子进行典范对应分析(CCA),结果表明影响夏季浮游植物群落结构变化的环境因子包括水温、营养盐(磷酸盐、硝酸氮、氨氮)、盐度等,且是各个环境因子相互作用的结果.  相似文献   
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