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631.
The Zijin heap bioleaching plant started operation by the end of 2005; due to the proximity of the Ting River, concerns rose about the migration of acidophiles outside of the heap. In this study, 53 soil samples and 51 liquid samples were collected, and the biogeographical distribution of acidophiles was investigated using clone libraries and real-time polymerase chain reaction (PCR), the physicochemical characteristics were analysed by Inductively Coupled Plasma Optical Emission Spectrometry (ICP). The results indicated the bioleaching system had some influence on the surrounding environment. Both microbial community and physiochemical index emerged correlation with distance of sampling sites from bioleaching system, mainly limited in the zone 30?m outside bioleaching system. Correlation analysis indicated the migration of different acidophiles was influenced by different factors. Leptospirillum had higher migration capability than the other acidophiles, and such migration capability was one of the important influence factors for its distribution. Environment factors and survival ability were the key influence factors for Acidithiobacillus, Sulfobacillus and Ferroplasma to survive in the surrounding environment.  相似文献   
632.
Critical loads are widely used in the effects-based assessment of emission reduction policies. While the impacts of acidification have diminished, there is increasing concern regarding the effects of nitrogen deposition on terrestrial ecosystems. In this context much attention has been focussed on empirical critical loads as well as simulations with linked geochemistry-vegetation models. Surprisingly little attention has been paid to adapt the widely used simple mass balance approach. This approach has the well-established benefit of easy regional applicability, while incorporating specified critical chemical criteria to protect specified receptors. As plant occurrence/biodiversity is related to both the nutrient and acidity status of an ecosystem, a single abiotic factor (chemical criterion) is not sufficient. Rather than an upper limit for deposition (i.e., critical load), linked nutrient nitrogen and acidity chemical criteria for plant occurrence result in an ‘optimal’ nitrogen and sulphur deposition envelope.  相似文献   
633.
根据2000~2005年长江上游干流宜宾、巴南和万州3个江段三层流刺网的监测资料,分析了春禁前后3年渔获物结构和鱼类生物多样性的变化,对长江上游春禁效果进行了初步评价。春禁前后3年共监测到鱼类51种,隶属于3目18科(亚科)36属,以鲤科鱼类为主,占608%。春禁后,渔获物主要种类优势度有所下降,部分江段单位捕捞努力量渔获量表现出一定上升趋势,3个江段Margalef指数、Pielou指数和Wilhm改进指数有一定升高,表明种类丰富度有所提高,群落结构趋于复杂,春季禁渔有一定效果。春禁前后渔获物种类的波动,可能与这些种类种群数量少,难以采到有关;春禁后主要种类平均体长、体重仍表现出下降趋势,可能与过度捕捞及资源在短期内难以恢复有关。建议延长禁渔期、严格控制禁渔结束后的捕捞强度等措施来提高禁渔效果,并采取恢复江湖联系、保护重要渔业水域水质、实施水利工程生态调度等措施来配合春禁制度的实施。长江渔业资源的恢复和保护是一个长期而复杂的过程,对长江禁渔效果的准确评估还需要长期监测和深入研究。  相似文献   
634.
This study investigated the effects of grassland conversion to croplands on soil organic carbon (SOC) in a typical grassland-dominated basin of the Inner Mongolia using direct field samplings. The results indicated that SOC contents decreased usually with increasing soil depth, with significant differences between the upper horizons (0-30cm) and the underlying horizons (30-100cm). Also, SOC densities decreased with an increase in the depth of soils. Average SOC densities in the upper horizons were 2.6-3.7 and 6.0-8.3kgCm(-2) for desert grassland-cropland sites (sites 1 and 2) and meadow-cropland sites (sites 3 and 4), respectively, with significant differences between grasslands and croplands (P<0.05). However, the SOC densities in the underlying horizons did not significantly differ between the land uses. The SOC densities up to 100cm depth were much higher in the meadow-cropland sites than in the desert grassland-cropland sites, reaching approximately 16 and 6kgCm(-2), respectively. The SOC: total nitrogen (TN) ratios were approximately 10, with no significant difference among the soil horizons of grasslands and croplands. The conversion of grasslands to croplands induced a slight loss of SOC, with a range of from -4% to 22% for the 0-100cm soil depth over about a 35-year period, in the temperate Inner Mongolia.  相似文献   
635.
典型重金属污染农田能源植物示范种植研究   总被引:10,自引:0,他引:10       下载免费PDF全文
为探索安全经济利用重金属中度-重度污染农田的模式,在浙江某典型重金属复合污染农田开展了能源植物(甜高粱Sweet sorghum、甘蔗Saccharum sinensisRoxb.、香根草Vetiveria和盐肤木Rhus chinensis)种植示范研究.结果表明,经施加0.1%的石灰和0.2%的磷矿粉改良后,土壤p...  相似文献   
636.
金沙江一期工程蓄水前后绥江段鱼类群落多样性特征   总被引:1,自引:0,他引:1  
为探索流域梯级水电开发对鱼类群落多样性影响,于2011年(蓄水前)和2015年(蓄水后)对金沙江下游绥江断面进行渔业资源调查,分析鱼类群落结构特征。结果表明,绥江段共计采集鱼类60种,隶属于5目12科,其中长江上游特有鱼类12种。蓄水前以瓦氏黄颡鱼(Pelteobagrus vachelli)、圆口铜鱼(Coreius guichenoti)、光泽黄颡鱼(Pelteobagrus nitidus)为优势种类;蓄水后以草鱼(Ctenopharyngodon idellus)、鳙(Aristichthys nobilis)、鲢(Hypophthalmichthys molitrix)为优势种类。与蓄水前相比,鱼类群落Margalef丰富度指数、Shannon-Weiner多样性指数、Pielou均匀度指数均呈现下降趋势,但无显著性差异(P0.05)。根据生态类群分析,静水缓流型鱼类由蓄水前54%增加到蓄水后的71%,河道洄游型鱼类从39%减少到20%,江湖洄游型鱼类蓄水前后变化不大。丰度生物量比较曲线显示,蓄水前绥江段鱼类群落未受到干扰,而蓄水后受到严重干扰。库区蓄水后总生物量有明显增加趋势,但优势种类趋于小型化、种类结构单一化。为科学保护金沙江下游流域鱼类生物多样性,建议成立鱼类保护区、开展梯级生态调度和加强流域环保预警研究等措施。  相似文献   
637.
科学监管评价生态保护红线区生态环境是合理利用自然资源和充分保护生态环境的基础,对推动国家生态文明建设具有重要意义。该研究基于“天-空-地”一体化获取多源数据,结合GIS和RS空间分析,从生态系统格局和质量、人类活动、环境限制4个方面选取25个指标,构建了生物多样性维护生态保护红线区监管评价体系,并以泰山生态保护红线区为例进行分析研究。结果表明:2000—2015年,研究区生态系统格局、生态系统质量、人类活动状况3个分指数得分及生态环境综合得分均呈现先降后升的趋势,就综合得分而言,2000—2005年、2005—2010年得分降幅分别为18.73%和5.24%,2010年得分最低(41.97分),而2010—2015年得分增幅为81.63%,2015年得分为76.23分,生态环境综合得分评价等级由Ⅱ级升为Ⅰ级。其中城乡居民和工矿用地面积占比、生态系统破碎度和分离度、植被生物量是影响研究区生态环境的关键指标,相关部门应加强对研究区边界处人类活动的监管,并注重生态系统完整性和植被生长状态的保护。该监管评价体系具有较强的实践性、科学性和可操作性,可为生态保护红线区的监管评价提供新思路。  相似文献   
638.
639.
India's forest biodiversity management regime is analysed at the policy, legal and institutional levels, from the perspective of the triple objectives of the Convention on Biological Diversity and the principles of the Indian constitution. The forest biodiversity management regime has both structural and functional flaws that render it largely incapable of facing the challenge of increasing biodiversity degradation and deepening poverty among the Adivasis and other forest‐dependent communities. The paper argues for the reform of the forest biodiversity management regime and offers recommendations in regard to most aspects of the regime, with a view of putting the country's conservation enterprise on a course that is effective, sustainable and inclusive, rejecting the report of the High Power Committee (HPC) (also known as the Subramanian Committee), which is premised on easing corporate access to forests.  相似文献   
640.
The need for enhanced environmental planning and management for highland aquatic resources is described and a rationale for integrated action planning is presented. Past action planning initiatives for biodiversity conservation and wetland management are reviewed. A reflective account is given of integrated action planning from five sites in China, India and Vietnam. Eight planning phases are described encompassing: stakeholder assessment and partner selection; rapport building and agreement on collaboration; integrated biodiversity, ecosystem services, livelihoods and policy assessment; problem analysis and target setting; strategic planning; planning and organisation of activities; coordinated implementation and monitoring; evaluation and revised target setting. The scope and targeting of actions are evaluated using the Driving forces, Pressures, State, Impacts and Responses framework and compatibility with biodiversity conservation and socio-economic development objectives are assessed. Criteria to evaluate the quality of planning processes are proposed. Principles for integrated action planning elaborated here should enable stakeholders to formulate plans to reconcile biodiversity conservation with the wise use of wetlands.  相似文献   
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