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451.
China will set up a national carbon emissions trading market by the end of 2017, which is initially open to individual investors from the initial market for business and institutional investors. In this article, the main influencing factors and mechanism of individual participation in carbon trading market are studied by establishing multiple linear regression model. The study found that age, education level, length of account opening time, and risk attitude are the main factors influencing the participation of individual investors. Environmental awareness and environmental impact are less affected; information transparency and transaction risk also have an impact on the degree of individual investor participation; investment experience does not affect the participation of individual investors in the carbon trading market. 相似文献
452.
Nobuo Ishiyama Kazuki Miura Takahiro Inoue Masanao Sueyoshi Futoshi Nakamura 《Conservation biology》2021,35(3):884-896
Forest conversion is one of the greatest global threats to biodiversity, and land-use change and subsequent biodiversity declines sometimes occur over a variety of underlying geologies. However, how forest conversion and underlying geology interact to alter biodiversity is underappreciated, although spatial variability in geology is considered an integral part of sustaining ecosystems. We aimed to examine the effects of forest conversion to farmland, the underlying geology, and their interaction on the stream fishes’ diversity, evenness, and abundance in northeastern Japan. We disentangled complex pathways between abiotic and biotic factors with structural equation modeling. Species diversity of stream fishes was indirectly shaped by the interaction of land use and underlying geology. Diversity declined due to nutrient enrichment associated with farmlands, which was mainly the result of changes in evenness rather than by changes in species richness. This impact was strongest in streams with volcanic geology with coarse substrates probably because of the differential responses of abundant stream fishes to nutrient enrichment (i.e., dominance) and the high dependency of these fishes on large streambed materials during their life cycles. Our findings suggest that remediation of deforested or degraded forest landscapes would be more efficient if the interaction between land use and underlying geology was considered. For example, the negative impacts of farmland on evenness were larger in streams with volcanic geology than in other stream types, suggesting that riparian forest restoration along such streams would efficiently provide restoration benefits to stream fishes. Our results also suggest that land clearing around such streams should be avoided to conserve species evenness of stream fishes. 相似文献
453.
454.
Robert Coats Melissa Larsen Alan Heyvaert James Thomas Matthew Luck John Reuter 《Journal of the American Water Resources Association》2008,44(3):754-770
Abstract: In efforts to control the degradation of water quality in Lake Tahoe, public agencies have monitored surface water discharge and concentrations of nitrogen, phosphorus, and suspended sediment in two separate sampling programs. The first program focuses on 20 watersheds varying in size from 162 to 14,000 ha, with continuous stream gaging and periodic sampling; the second focuses on small urbanized catchments, with automated sampling during runoff events. Using data from both programs, we addressed the questions (1) what are the fluxes and concentrations of nitrogen and phosphorus entering the lake from surface runoff; (2) how do the fluxes and concentrations vary in space and time; and (3) how are they related to land use and watershed characteristics? To answer these questions, we calculated discharge‐weighted average concentrations and annual fluxes and used multiple regression to relate those variable to a suite of GIS‐derived explanatory variables. The final selected regression models explain 47‐62% of the variance in constituent concentrations in the stormwater monitoring catchments, and 45‐72% of the variance in mean annual yields in the larger watersheds. The results emphasize the importance of impervious surface and residential density as factors in water quality degradation, and well‐developed soil as a factor in water quality maintenance. 相似文献
455.
Kate Hughes 《补救:环境净化治理成本、技术与工艺杂志》2017,28(1):73-86
Words matter in risk communication, and experts’ choice of words is critical when remediation risks are being explained to nonexperts. In risk communication studies, communication gaps between experts and nonexperts are investigated but there is lack of primary research. An Australian project addresses this shortcoming through research into communication about the risks of contaminated land remediation, and this paper provides some of its findings. Seventeen experts completed a questionnaire about the meaning of some scientific terms, and analysis found that they have capacity to improve communication through their selection and use of language. When experts undertake risk communication, the language they use may increase or reduce communication gaps. When the topic is uncertainty about health risks, communication gaps about the extent of uncertainty may reduce the effectiveness of social engagement, leading to unintended consequences such as cost overruns. This situation makes for a good case study since remediation is about benefit as well as risk, and communication about benefit, while desirable, may not always be achievable. The study suggests how to improve risk communication by exploring the accuracy, clarity, and depth of expert language. It identifies attributes of language that can bridge gaps in knowledge and understanding and characterizes them as integration mechanisms. These are defined as knowledge forms and mental processes that support cooperation between different epistemic communities to achieve mutually agreed outcomes. Two integration mechanisms are suggested. Bridging content addresses communication gaps through the selection of content (what knowledge is selected). Bridging process addresses communication gaps through the use of language (how knowledge is explained). Bridging content and bridging process can be expressed through cognitive and experiential platforms, or a blending of both, so whether words are positioned in the science‐based or mental model of risk communication, a utility value can be found in their quality, whether reflected by accuracy or the power to communicate meaning. 相似文献
456.
多水源供水管网中铁释放规律 总被引:1,自引:0,他引:1
针对水源切换而引起的水质超标现象,开展了多水源联合供水条件下管网中铁释放规律的研究。分析了北方某城市2种水源(滦河水和长江水)的水质特点,利用实验模拟反应器分别研究了水源完全置换和供水分界线处水源混合区域的铁释放规律。结果表明,多水源供水管网的铁释放速率与水源水质密切相关,特别是水中含高浓度SO2-4和氯化物时会加快铁的释放。不同水源之间的频繁切换会破坏管垢表面的钝化层,使铁释放速率迅速变化,随后会有所缓解,但新的平衡的形成需要较长时间。供水分界线处的水源混合区域,由于水质的不断变化造成管垢表面很难形成稳定的钝化层,铁释放速率持续偏高,只有当长江水所占比例高达75%以上时才能得到抑制。 相似文献
457.
从污染环境分离和筛选得到了9株PAHs降解菌,以其为基本菌种,构建高效修复PAHs复合污染体系的菌群(D)。采用平板稀释涂布计数法对降解体系中菌群(D)的动态结构进行了解析,数据显示菌群内的微生物在降解过程中能相互协作,发挥稳定且高效的降解作用。实验进一步研究了菌群D对单一PAH和混合PAHs的降解特性,结果表明,无论对单一PAH还是混合PAHs,菌群D均具有较强的降解能力。当降解历时6 d,菌群D能使40 mg/L的单一PAH平均降解85.8%,使60 mg/L的混合PAHs平均去除89.4%。菌群D在多环芳烃复合污染体系的生物修复方面具有潜在的应用价值。 相似文献
458.
459.
In order to reduce the impact of eutrophication caused by agricultural residues (i.e. excess nitrate) in aqueous solution, economic and effective anionic sorbents are required. In this article, we prepared anionic sorbent using wheat straw. Its structural characteristics and adsorption properties for nitrate removal from aqueous solution were investigated. The results indicate that the yield of the prepared anionic sorbent, the total exchange capacity, and the maximum adsorption capacity were 350%, 2.57 mEq/g, and 2.08 mmol/g, respectively. The Freundlich isotherm mode is more suitable than the Langmuir mode and the adsorption process accords with the first order reaction kinetic rate equation. When multiple anions (SO42-, H2PO4-, NO3-, and NO2-) were present, the isotherm mode of prepared anionic sorbent for nitrate was consistent with Freundlich mode; however, the capacity of nitrate adsorption was reduced by 50%. In alkaline solutions, about 90% of adsorbed nitrate ions could be desorbed from prepared anionic sorbent. The results of this study confirmed that the wheat straw anionic sorbent can be used as an excellent nitrate sorbent that removes nitrate from aqueous solutions. 相似文献
460.
1980~2010年江苏沿海城市土地利用变化及其与环境因子关系分析——以东台市为例 总被引:1,自引:0,他引:1
2009年江苏省沿海开发规划上升为国家战略,了解江苏沿海城市过去土地利用变化轨迹以及驱动因子是未来江苏省沿海城市土地利用规划的重要基础性工作。基于5期TM30 m×30 m RS遥感影像和GIS技术,分析东台市1980~2010年土地利用结构与变化轨迹,并通过典型对应分析(CCA)分析其与环境因子之间的关系。结果表明,东台市1980~2010年主要土地利用类型为耕地(2029.02 km2)、建设用地(155.31 km2)、草地(60.41 km2)和水域(56.56 km2)。近30年土地利用变化量占总面积的16.98%,其中耕地、草地和建设用地变化量最大。土地利用变化最主要轨迹为耕地转建设用地,主要位于市区及周边地区,其次为草地转耕地,主要位于海岸带地区。东台市土地利用变化热点区域分别为市中心和海岸带,二者相距较远,相对独立。CCA分析显示城镇、交通和斑块形状复杂程度等是影响沿海城市土地利用变化的重要因子,海岸线作为沿海城市主要特征,随着海岸滩涂围垦开发,到海岸距离也是沿海城市土地利用变化的重要影响因子。因此,在沿海城市土地利用规划中需要重点考虑城镇布局、交通等基础设施分布、斑块的形状等因子,通过海岸带土地利用方式转变来加强市区与海岸带之间联系,促进社会经济转变,进一步保护海岸生态环境,提高海岸开发综合效益,引导土地利用走向可持续发展道路。 相似文献