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741.
742.
退田还湖后替代生计的经济评估研究——以洞庭湖西畔山洲垸为例 总被引:8,自引:0,他引:8
分析了“湿地保护项目是如何改善民众生计的”这一问题。采用2000~2005年1 474个农户调查问卷作为基本数据,其中964个农户位于洞庭湖西畔山洲垸。得出6个结论:①WWF在西畔山洲垸的替代生计示范项目增加了农户的收入和福利,降低了脆弱性,增强可持续利用的自然资源基础;②妇女、老人以及低收入群体从项目中获益;③参加项目的农户比未参加项目的农户拥有更多的收入和财产;④与2000年项目开始时相比,生计水平有了持续的改善;⑤生计改善的原因是当地社区的积极参与、国家政策机遇、伙伴关系的建立、社区基层组织建设以及适应性管理方法的应用;⑥鱼类和水鸟等返回已恢复的湿地。表明该示范项目达到了自然保护目标。 相似文献
743.
新型高效絮凝剂生物聚合硫酸铁的制备及性能研究 总被引:1,自引:0,他引:1
利用恒化器原理和SBR技术 ,以FeSO4为原料 ,用经过驯化培养的微生物为催化剂 ,在常温常压下用空气氧化 ,连续生产或序批式生产生物聚合铁 ,产品性能稳定 ,投资少 ,设备简单 ,操作方便 ,无污染 ,可实现清洁生产 ,生产成本极低。试验证明 :生物聚合铁性能优良 ,除浊、除有机物性能好 ,对pH适应范围宽 ,对水温不敏感 ,对低温、低浊水有很好的处理效果 ,凝聚作用显著 ,处理效果明显优于普通聚合铁 ,是一种新型高效絮凝剂。 相似文献
744.
从定性研究逐步向定量化分析发展,是土壤DDT残留时间研究的必然趋势。初步探讨了土壤中DDT残留时间的定量表征,设计出归一化的DDT残留时间指数(NRTI)作为定量表征土壤DDT残留时间的方法之一。根据对天津土壤中残留DDT的采样监测结果的计算和分析,发现NRTI在表征DDT的残留时间问题上,相对于传统方法有一定的改进。 相似文献
745.
束缚装置选型是新版中国标准中增加的一项重要内容,中国标准借鉴了美国标准和欧盟标准,但并未完全采用.因此,进行中国标准、美国标准和欧盟标准的比较研究非常重要.本文从人体坐标系、加速度区域和束缚装置准则三个方面对中国标准、美国标准和欧盟标准中的相关内容进行了全面对比,分析了各自的优缺点.在人体坐标系方面,中国标准定义较为合... 相似文献
746.
747.
用室内模拟放矿实验方法得出了无底柱分段崩落法合理结构参数 ,运用这一成果可使经济优化、环境改善。 相似文献
748.
This paper identifies a line of reasoning based on a number of concepts and tools to facilitate river basin management, which
have been applied in a case study. For long-term sustainable river basin management, a balance is needed between the human
use of the river and its basin, the ecological functioning of the river and receiving waters, and the river's capacity to
supply goods and services. To find such a balance a framework is needed that illustrates and clarifies possible trade-offs
between economic use and environmental supply by integrating scientific information on cause–effect chains on a catchment
scale. A number of concepts and tools are proposed as a basis for this framework. The tools are: (1) indicators that describe
the complex interactions and processes in rivers; (2) a suite of linked models that predict the economic, environmental and
ecological effect of management measures; (3) an evaluation framework to rank different management alternatives on the basis
of three objectives: economic efficiency, spatial equity in costs and benefits and environmental quality of the river and
receiving lakes. The concept of environmental quality defines the potential of the river environment (i.e. natural capital)
to contribute to human welfare. The concept of environmental functions is used to identify societal interest in natural capital.
The concept and tools have been applied in a case study involving the evaluation of four management strategies on nutrient
abatement in the Rhine basin. The result of the case study is that economic efficiency is in conflict with spatial equity
and environmental quality. Spatial equity is in agreement with environmental quality.
Electronic Publication 相似文献
749.
基于闽台对比的福建耕地变化趋势演绎 总被引:4,自引:0,他引:4
闽台因其区域自然背景及历史文化的相似性和经济发展时序递差性成为区域对比研究的理想对象之一。利用闽台相关统计资料对比显示,闽台耕地变化共同呈现出先增后减、时有波动、总体减少的特点,但台湾耕地的先增后减时序后移,并且减少的总趋势较缓。以各市县平均耕地产出计算,福建新增耕地质量低于被占耕地质量,而台湾正好相反。文章最后通过对福建2010年耕地面积的多元回归预测以及闽台耕地对比演绎,说明福建要实现耕地保护目标,除了依靠严格的耕地保护政策外,依靠农业以及非农业的发展,提高现有耕地综合生产力更为重要。 相似文献
750.
Adel Ahmed Mohamed Abdel-Aleem Marzooka Shaban Abdel-Tawab Mohamed El-Kassem M. Hassouna 《环境质量管理》2023,32(4):119-135
Natural, acid and base modified kaolin clays were studied for the sake of phenol and 4-chlorophenol removal from aqueous environments and their application to real ground and industrial wastewater samples. Scanning electron microscope (SEM), infrared spectroscopy (IR), X-ray diffraction (XRD), Thermo Gravimetric Analysis (TGA), Differential Thermal Analysis (DTA), and Surface area analysis were employed for characterization of the adsorbents microstructure. Operating factors such as adsorbent dose, solution pH, initial phenol concentration, and contact time were studied. The experimental data displayed that the increase of the adsorbent dose, contact time, and pH value from 2 to 7 increases the efficiency of the removal process. Optimal conditions for phenolic removal were; contact time of 300 min, primary phenol solution of 25 mg/L, pH 7 and 2.5 g/L as an appropriate adsorbent dose using crude (natural), acid modified and base modified kaolin clays. The higher phenolic removal efficiencies were obtained at 5 mg/L as 90, 97, 96.2%, respectively, for the adsorbents in the previously mentioned order. The adsorption capacity in the removal of phenol and 4-chlorophenol were 7.481 and 4.195, 8.2942 and 3.211, and 8.05185 and 18.565 mg/g, respectively, for the adsorbents in the same mentioned order. The adsorption equilibrium data were fitted and analyzed with four isotherm models, namely, Langmuir, Freundlich, Temkin, and Dubinin–Radushkevich isotherm equations. The adsorption process of phenol on studied adsorbents was exothermic, spontaneous and thermodynamically favorable proved by the negative values of their thermodynamic parameters ΔH° and ΔG°. The correlation coefficient (R2) for all concentrations was higher than 0.94, which indicates that in the studied system, the data suitably fit the first-order kinetics. The % desorption capacity was amounted to 96%, 91.11%, and 87.06% of adsorbed phenol, respectively, for the adsorbents in the previous order using 0.1N NaOH and 10% V/V ethanol solutions as eluents at 25°C, indicating the reusability of the adsorbents. Kaolin and its modified forms can be introduced as eco-friendly and low-cost adsorbents in water remediation implementation. 相似文献