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1.
Waste-to-energy is a promising approach to face the current challenge of waste overproduction in Reunion Island, a French territory. In this particular context of an isolated and tropical territory, it is essential to study the properties of potential feedstocks to choose the most appropriate conversion process. This article reports on the composition of Residual Household Waste from Reunion Island and its physico-chemical parameters. Twelve representative samples of Residual Household Waste were subjected to thermal and elemental analysis. The results showed that their composition had a significant influence on the physico-chemical properties, including calorific value. Residual Household Waste from the selective sorting (rich in wood, plastic, and sanitary textiles) as well as dry mixed RHW are the most interesting for energy recovery. Due to their high volatile matter and high carbon content, and their low moisture content, these types of waste have a high calorific value exceeding 18 MJ/kg. Furthermore, the RHW sample comply with the environmental and health criteria applied by French regulations concerning halogen and heavy metal. Thus, it seems that Residual Household Waste can be an alternative to conventional fuels used in incineration or pyro-gasification processes. However, the study also points the need for a pre-treatment process for these wastes. Indeed, it is necessary to sort them correctly in order to avoid the risks of pollution and important maintenance. And more importantly, drying beforehand is unavoidable to improve combustibility and obtain optimal energy conversion.  相似文献   
2.
Urbanization and mass movement of the population from rural areas and small cities to megacities have led to environmental, economic, and social problems in Iran. In dealing with these challenges, assessing resource and environmental carrying capacity (RECC) is considered an effective method to leverage space and capital to achieve sustainable development. This study aimed to rank the provincial RECC in Iran. Toward this purpose, environmental indices were generated from remotely sensed and statistical census data. Then, the provinces were scored in terms of environmental, economic, and infrastructural carrying capacities, and RECC using the mean variance analysis method. Results demonstrated that in most areas, there is no relationship between economic and infrastructural capacities and development. Statistically, a correlation coefficient of −0.53 between economic and environmental carrying capacities indicated excessive use of environmental capacities. Moreover, the spatial distribution pattern of environmental, economic, and infrastructural carrying capacity was entirely heterogeneous between the provinces; there was a northeast–southwest pattern in terms of infrastructural capacity and an economic pattern from north to south. The distribution pattern of RECC is most consistent with the environmental capacity, pointing at the high weight of the indicators of the RECC model. In conclusion, this research offers a new vision for policymakers and provides a theoretical and applicable framework for implementing sustainable strategies in land-use planning. It is recommended that the RECC concept and tools can be used not only for planning but also for measuring the efficiency of spatial development programs and establishing land balances in the region.  相似文献   
3.
The sharing of environmental cost by residents in various residential areas in the developing world is perceived to be unfair. This study therefore assessed residents’ experiences of environmental justice in Ile-Ife, Nigeria. Three residential areas were identified in the study area and samples were selected using systematic sampling. Using availability and condition of urban infrastructure, severity of environmental problems and residents’ involvement in environmental issues, the study examined environmental justice in the study area. The study established a variation in environmental issues across identified residential areas. The severity of environmental problem measured through an index tagged Severity of Environmental Problem (SEPI) revealed that environmental problems was most severe in the core (SEPI = 4.00), followed by the peripheral area (SEPI = 3.71) and least in the transition area (SEPI = 3.56). On the condition of available environmental infrastructure, the study revealed that the conditions of infrastructure were most improved in the peripheral area (ICI = 3.07), followed by the core (ICI = 2.67) and the least in the transition area (ICI = 2.42). The study concluded that residents’ experiences of environmental justice differ significantly across the different residential zones as reflected by residents’ socio-economic characteristics. Furthermore, it established that age, gender, educational status, and number of years spent in the area can be used to explain the differences in residents’ experience of environmental justice in the study area. To enhance the liveability, the study recommends adequate provision of environmental amenities needed by each category of people in the city.  相似文献   
4.
为了探索盐渍化土壤中微生物多样性及群落构成,有效筛选盐渍土壤中耐盐微生物菌群.采用高通量测序技术对采集的河北省滨海盐渍土(原生盐渍化)、设施盐渍土(次生盐渍化)和高产粮田(健康土壤)3个生境的耕层土壤样本细菌和真菌多样性、群落结构、网络关系及其影响因子进行测定.结果表明,与大田土壤相比,设施土壤中OM、AP、AK、TS和EC显著升高,滨海盐渍土壤的TS和EC显著升高,其他养分指标则显著降低.细菌α多样性依次为:设施盐渍土>高产粮田>滨海盐渍土,真菌α多样性则为高产粮田显著高于设施盐渍土和滨海盐渍土.在门和属水平上分析盐渍化土壤的菌群结构,细菌群落中绿弯菌门(Chloroflexi)及其菌属和真菌群落中子囊菌门(Ascomycota)及其中有益菌Trichocladium和病原菌Fusarium为盐渍化土壤中的优势微生物类群.土壤EC和TS两个盐分因子是对细菌和真菌菌群分布贡献最大的因子,与绿弯菌门中unclassified_A4b和unclassified_Chloroflexi以及变形菌门中unclassified_α-Proteobacteria等细菌菌属和子囊菌门中Trichocladium、unclassified_ChaetomiaceaeCrassicarponCephaliophoraSodiomyces等真菌菌属呈显著正相关.研究结果为盐渍化土壤修复所需的微生物资源筛选提供了理论依据.  相似文献   
5.
Conservation practitioners, natural resource managers, and environmental stewards often seek out scientific contributions to inform decision-making. This body of science only becomes actionable when motivated by decision makers considering alternative courses of action. Many in the science community equate addressing stakeholder science needs with delivering actionable science. However, not all efforts to address science needs deliver actionable science, suggesting that the synonymous use of these two constructs (delivering actionable science and addressing science needs) is not trivial. This can be the case when such needs are conveyed by people who neglect decision makers responsible for articulating a priority management concern and for specifying how the anticipated scientific information will aid the decision-making process. We argue that the actors responsible for articulating these science needs and the process used to identify them are decisive factors in the ability to deliver actionable science, stressing the importance of examining the provenance and the determination of science needs. Guided by a desire to enhance communication and cross-literacy between scientists and decision makers, we identified categories of actors who may inappropriately declare science needs (e.g., applied scientists with and without regulatory affiliation, external influencers, reluctant decision makers, agents in place of decision makers, and boundary organization representatives). We also emphasize the importance of, and general approach to, undertaking needs assessments or gap analyses as a means to identify priority science needs. We conclude that basic stipulations to legitimize actionable science, such as the declaration of decisions of interest that motivate science needs and using a robust process to identify priority information gaps, are not always satisfied and require verification. To alleviate these shortcomings, we formulated practical suggestions for consideration by applied scientists, decision makers, research funding entities, and boundary organizations to help foster conditions that lead to science output being truly actionable.  相似文献   
6.
● China has pledged ambitious carbon peak and neutrality goals for mitigating global climate change. ● Major challenges to achieve carbon neutrality in China are summarized. ● The new opportunities along the pathway of China’s carbon neutrality are discussed from four aspects. ● Five policy suggestions for China are provided. China is the largest developing economy and carbon dioxide emitter in the world, the carbon neutrality goal of which will have a profound influence on the mitigation pathway of global climate change. The transition towards a carbon-neutral society is integrated into the construction of ecological civilization in China, and brings profound implications for China’s socioeconomic development. Here, we not only summarize the major challenges in achieving carbon neutrality in China, but also identify the four potential new opportunities: namely, the acceleration of technology innovations, narrowing regional disparity by reshaping the value of resources, transforming the industrial structure, and co-benefits of pollution and carbon mitigation. Finally, we provide five policy suggestions and highlight the importance of balancing economic growth and carbon mitigation, and the joint efforts among the government, the enterprises, and the residents.  相似文献   
7.
Sectorial approach for monitoring heavy metal pollution in rivers has failed to report realistic pollution status and associated ecological and human health risks. The increasing spread of heavy metals from different sources and emerging risks to human and environmental health call for reexamining heavy metal pollution monitoring frameworks. Also, the sources, spread, and load of heavy metals in the environment have changed significantly over time, requiring consequent modification in the monitoring frameworks. Therefore, studies on heavy metal monitoring in rivers conducted in the last decade were evaluated for experimental designs, research frameworks, and data presentations. Most studies (∼99%) (i) lacked inclusiveness of all environmental compartments; (ii) focused on “one pollutant – one/two compartment” or sometimes “one pollutant – one compartment – one effect” approach; and (iii) remained “data-rich but information poor.” An ecological approach with integrative system thinking is proposed to develop a holistic approach for monitoring river pollution. It is visualized that heavy metal monitoring, risk analyses, and water management must incorporate tracking pollutants in different environmental compartments of a river (water, sediment, and floodplain/bank soil) and consider correlating it with riverbank land use. The systems-based pollution monitoring and assessment studies will reveal the critical factors that drive heavy metals pollutant movement in ecosystems and associated potential risks to the environment, wildlife, and humans. Also, water quality and pollution indexing tools would help better communicate complex pollution data and associated risks among all stakeholders. Therefore, integrating systems approaches in scientific- and policy-based tools would help sustainably manage the health of rivers, wildlife, and humans.  相似文献   
8.
Water quality is a critical challenge in Asia in the context of growing industrialization, urbanization, and climate change. Nature-based solutions (NbS) could play an important role in reducing urban water pollution, while generating multiple co-benefits that could make cities more liveable and resilient. In this regard, a number of pilot and demonstration projects have been set up to explore their potential across cities in Asia. Their effectiveness and impacts, however, have not been adequately documented, thus how they can be sustained, replicated and up-scaled remain poorly understood. This study aims to contribute to addressing this challenge by co-developing an integrated assessment framework and employing it to understand how existing evaluations of NbS in the region can be improved. It focuses specifically on a set of nature-based solutions that have been employed for water treatment across six cities in Southeast Asia (two in each Sri Lanka, the Philippines, and Vietnam), namely, floating wetlands, constructed wetlands and maturation ponds. The study also suggests specific methodologies for capturing a set of core indicators considered relevant for assessing the effectiveness and capturing the multi-faceted impacts of the examined NbS.  相似文献   
9.
利用2006—2017年我国30个省级行政单位的面板数据,采用空间计量模型对财政分权与环境污染之间的关系进行实证分析,并通过效应分解分别计算出财政收入分权和财政支出分权对环境污染的直接效应、空间溢出效应和总效应。模型估计的结果表明:①财政收入分权与财政支出分权通过直接效应和空间溢出效应两种途径对环境污染产生显著影响,但收入分权与支出分权对环境污染的空间效应具有异质性。②财政收入分权对环境污染具有显著的负向直接效应和负向空间溢出效应,影响系数分别为-5.429和-17.572。提高财政收入分权度不仅有利于减轻本省份环境污染,也对邻近省份的环境污染起到抑制作用。而财政支出分权对环境污染具有显著的负向直接效应和正向的空间溢出效应,影响程度分别为-3.345和1.173。提高财政支出分权虽然有利于减少本省份污染的排放,但在一定程度上引起省际的污染外溢效应,提高邻近省份的污染程度。③从总效应来看,财政收入分权和财政支出分权对环境污染均呈现出显著的负向相关性,影响程度分别为-23.001和-2.172。提高财政分权可降低环境污染水平,有利于环境质量提升。④通过构建不同空间权重矩阵,检验模型的稳健性,结果表明模型估计是稳健可靠的。根据分析结论,可能的启示与建议有:①合理划分中央政府和地方政府之间的财政事权和支出责任,在提高财政支出分权度的同时提高地方政府财政收入分权度,充分发挥地方政府环境治理的积极性和主动性。②继续加大生态环境保护力度,完善绿色经济考核机制,引导地方政府加大对污染治理和环境改善的支出水平及效率。  相似文献   
10.
Waste accumulation is a grave concern and becoming a transboundary challenge for environment. During Covid-19 pandemic, diverse type of waste were collected due to different practices employed in order to fight back the transmission rate of the virus. Covid-19 was proved to be capricious catastrophe of this 20th century and even not completely eradicated from the world. The havoc created by this imperceptible quick witted, pleomorphic deadly virus can't be ignored. Though a number of vaccines have been developed by the scientists but there is a fear of getting this virus again in our life. Medical studies prove that immunity drinks will help to reduce its reoccurrences. Coconut water is widely used among all drinks available globally. Its massive consumption created an incalculable pile of green coconut shells around the different corners of the world. This practice generating enormous problem of space acquisition for the environment. Both the environment and public health will benefit from an evaluation of quantity of coconut waste that is being thrown and its potential to generate value added products. With this context, present article has been planned to study different aspects like, coconut waste generation, its biological properties and environmental hazards associated with its accumulation. Additionally, this review illustrates, green technologies for production of different value added products from coconut waste.  相似文献   
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