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1.
Environmental Science and Pollution Research - Hydrothermal liquefaction (HTL) of biomass used HTL reaction under high temperature and pressure to produce bio-oil. This technology is considered as...  相似文献   
2.
Environmental Chemistry Letters - Tin oxide nanoparticles (SnO2 NPs) with a diameter less than 10 nm are usually used in waste water treatment via the photocatalytic reaction. However,...  相似文献   
3.
Considerable empirical evidence supports recovery of reef fish populations with fishery closures. In countries where full exclusion of people from fishing may be perceived as inequitable, fishing‐gear restrictions on nonselective and destructive gears may offer socially relevant management alternatives to build recovery of fish biomass. Even so, few researchers have statistically compared the responses of tropical reef fisheries to alternative management strategies. We tested for the effects of fishery closures and fishing gear restrictions on tropical reef fish biomass at the community and family level. We conducted 1,396 underwater surveys at 617 unique sites across a spatial hierarchy within 22 global marine ecoregions that represented 5 realms. We compared total biomass across local fish assemblages and among 20 families of reef fishes inside marine protected areas (MPAs) with different fishing restrictions: no‐take, hook‐and‐line fishing only, several fishing gears allowed, and sites open to all fishing gears. We included a further category representing remote sites, where fishing pressure is low. As expected, full fishery closures, (i.e., no‐take zones) most benefited community‐ and family‐level fish biomass in comparison with restrictions on fishing gears and openly fished sites. Although biomass responses to fishery closures were highly variable across families, some fishery targets (e.g., Carcharhinidae and Lutjanidae) responded positively to multiple restrictions on fishing gears (i.e., where gears other than hook and line were not permitted). Remoteness also positively affected the response of community‐level fish biomass and many fish families. Our findings provide strong support for the role of fishing restrictions in building recovery of fish biomass and indicate important interactions among fishing‐gear types that affect biomass of a diverse set of reef fish families.  相似文献   
4.
三峡库区消落带农用坡地磷素径流流失特征   总被引:1,自引:0,他引:1  
消落带是三峡库区重要的生态交错带,但自发农用和无序开发可能会造成更多的氮磷流失,进而加剧三峡库区水体富营养化。通过对库区连续3 a的定位监测(2011~2013年),研究了三峡库区消落带农用坡地的磷素流失特征。结果表明:次降雨事件中常规施肥处理的地表径流、壤中流总磷平均浓度分别为0.848±0.153、0.140±0.006 mg/L,其中地表径流中磷的形态以颗粒态为主,壤中流以溶解态的生物可利用磷为主。常规施肥下,地表径流、壤中流磷素年均流失通量分别为0.236±0.004、0.100±0.003 kg·hm 2,地表径流、壤中流磷素流失通量分别占总流失通量的70.2%、29.8%,地表径流是坡地磷素流失的主要途径,但壤中流也是不可忽视的重要途径。与常规施肥处理相比,减量施肥处理地表径流、壤中流磷素流失量分别降低了45.3%、40.0%。建议采取减量施肥的方式,以降低营养盐负荷,保护水环境。  相似文献   
5.
基于探索性数据分析的汉丰湖富营养化驱动因子研究   总被引:2,自引:0,他引:2  
为了探究汉丰湖富营养化驱动因子和营养状况,基于2014年水质监测数据,应用探索性数据分析方法初步研究了汉丰湖水动力条件与环境因子的相关性、水质主成分、相关环境因子熵权和营养健康指数。回归分析结果表明:水位与透明度呈正相关,流量与DO呈负相关,与流速呈负相关的因子为Chla、CODMn、NH+4-N和DTP;主成分分析提取的3个主成分分别反映了营养盐、有机污染以及藻类信息;DO、TN和TP的熵权表明汉丰湖水体的富营养状况受制于耗氧有机污染和氮、磷营养盐;营养健康指数S1>S3>S6(湖心)>S7(湖尾)>S5(湖首)>S4>S2。汉丰湖水体营养状况介于中营养到轻富营养,其中南河营养状态较高,湖心营养程度高于湖首和湖尾。减少有机污染物、营养盐的输入和改善局部水域的水动力条件可抑制藻类生长,有利于防治富营养化。 关键词: 探索性数据分析;汉丰湖;富营养化;驱动因子;水动力条件;主成分;熵权;营养健康指数  相似文献   
6.
Unsustainable wildlife trade affects biodiversity and the livelihoods of communities dependent upon those resources. Wildlife farming has been proposed to promote sustainable trade, but characterizing markets and understanding consumer behavior remain neglected but essential steps in the design and evaluation of such operations. We used sea turtle trade in the Cayman Islands, where turtles have been farm raised for human consumption for almost 50 years, as a case study to explore consumer preferences toward wild‐sourced (illegal) and farmed (legal) products and potential conservation implications. Combining methods innovatively (including indirect questioning and choice experiments), we conducted a nationwide trade assessment through in‐person interviews from September to December 2014. Households were randomly selected using disproportionate stratified sampling, and responses were weighted based on district population size. We approached 597 individuals, of which 37 (6.2%) refused to participate. Although 30% of households had consumed turtle in the previous 12 months, the purchase and consumption of wild products was rare (e.g., 64–742 resident households consumed wild turtle meat [i.e., 0.3–3.5% of households] but represented a large threat to wild turtles in the area due to their reduced populations). Differences among groups of consumers were marked, as identified through choice experiments, and price and source of product played important roles in their decisions. Despite the long‐term practice of farming turtles, 13.5% of consumers showed a strong preference for wild products, which demonstrates the limitations of wildlife farming as a single tool for sustainable wildlife trade. By using a combination of indirect questioning, choice experiments, and sales data to investigate demand for wildlife products, we obtained insights about consumer behavior that can be used to develop conservation‐demand‐focused initiatives. Lack of data from long‐term social–ecological assessments hinders the evaluation of and learning from wildlife farming. This information is key to understanding under which conditions different interventions (e.g., bans, wildlife farming, social marketing) are likely to succeed.  相似文献   
7.

While progress has been made in reducing external nutrient inputs to the Baltic Sea, further actions are needed to meet the goals of the Baltic Sea Action Plan (BSAP), especially for the Baltic Proper, Gulf of Finland, and Gulf of Riga sub-basins. We used the net anthropogenic nitrogen and phosphorus inputs (NANI and NAPI, respectively) nutrient accounting approach to construct three scenarios of reduced NANI-NAPI. Reductions assumed that manure nutrients were redistributed from areas with intense animal production to areas that focus on crop production and would otherwise import synthetic and mineral fertilizers. We also used the Simple as Necessary Baltic Long Term Large Scale (SANBALTS) model to compare eutrophication conditions for the scenarios to current and BSAP-target conditions. The scenarios suggest that reducing NANI-NAPI by redistributing manure nutrients, together with improving agronomic practices, could meet 54–82% of the N reductions targets (28–43 kt N reduction) and 38–64% P reduction targets (4–6.6 kt P reduction), depending on scenario. SANBALTS output showed that even partial fulfillment of nutrient reduction targets could have ameliorating effects on eutrophication conditions. Meeting BSAP targets will require addressing additional sources, such as sewage. A common approach to apportioning sources to external nutrients loads could enable further assessment of the feasibility of eutrophication management targets.

  相似文献   
8.
提出了一种新的污泥板框调理剂综合评价方法。传统的CST(毛细吸水时间)、污泥比阻、泥饼含水率等指标只能单一地评价泥饼脱水效果,为了实现对调理效果的综合评价,需要考虑药剂调理费用、运输处置成本、设备处理产能、滤液处理难度等多种因素。通过长期采集中试运行数据,考察了3种污泥板框调理剂对设备、泥饼、滤液和运行4个方面17个指标的影响。引入层次分析法和模糊数学综合评价法相结合的模糊层次分析法(FAHP)对3种污泥板框调理剂进行了综合评价,采用层次分析法确定指标权重;采用隶属函数对指标进行无量纲化处理,确定其隶属度,解决了指标间的可综合性问题;最后用加权平均法得出评价综合值,综合评价值表明,在这3种调理剂中,调理剂1的综合效果最优,更适合作为该厂的污泥板框脱水调理剂。  相似文献   
9.
10.
This paper explores the level of vulnerability to the hazard of fire that exists in Makola Market in Accra, Ghana, and assesses how this threat can be reduced through a community‐based risk assessment. It examines the perceptions of both market‐stall occupants and primary stakeholders regarding the hazard of fire, and analyses the availability of local assets (coping strategies) with which to address the challenge. Through an evaluation of past instances of fire, as well as in‐depth key stakeholder interviews, field visits, and observations, the study produces a detailed hazard map of the market. It goes on to recommend that policymakers consider short‐to‐long‐term interventions to reduce the degree of risk. By foregrounding the essence of holistic and integrated planning, the paper calls for the incorporation of disaster mitigation measures in the overall urban planning process and for the strict enforcement of relevant building and fire safety codes by responsible public agencies.  相似文献   
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