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991.
The REDD+ (Reducing Emissions from Deforestation and Forest Degradation) partnership works to promote the reduction of greenhouse gas (GHG) emissions by protecting forests in developing countries through positive incentives. It is regarded as an essential component of the post‐2012 climate regime to stabilize GHG emissions and engage developing countries in worldwide mitigation endeavours. This study focuses on the gap between agricultural revenue and REDD+ compensation through the construction of several scenarios that explore the impacts of possible carbon price ranges.Three scenarios that reflect different potential policies are examined: (1) current carbon trading; (2) carbon trading with all forestry activities; and (3) carbon trading with all countries participating gradually over the coming decades. Data for developing the scenarios were obtained through a case study in central Kalimantan, Indonesia, by interrogating the potential for revenue by expanding agricultural land. The results indicate that REDD+ payments could not effectively compensate land users for their opportunity cost of deforestation, making it difficult for the governments to ensure that REDD+ money “reaches the ground” in terms of balancing the agricultural revenue of land users. 相似文献
992.
Recently, environmental protection and regulations such as WEEE, ELV, and RoHS are rapidly emerging as an important issue for business to consider. The trend of swinging from end-of-pipe control to product design, green innovation, and even the establishment of image or brand has affected corporations in almost every corner in the world, and enlarged to the all modern global production network. Corporations must take proactive environmental strategies to response the challenges. This study adopts balanced scorecard structure and aim at automobile industries to understand the relationships of internal and external, financial and non-financial, and outcome and driving factors. Further relying on these relationships to draw the “map of environment strategy” to probe and understand the feasibility of environmental performance evaluation and environmental strategy control. 相似文献
993.
采用截留分子量(MWCO)为5000 Dalton、1000 Dalton的聚砜超滤膜,MWCO为1 kDa的再生纤维素超滤膜;采用十二烷基苯磺酸钠(SDBS)、曲拉通100(TritonX-100)、吐温80(Tween-80)、烷基多苷(APG)为表面活性剂,用胶团强化超滤工艺去除水中双酚A。研究了不同材质和截留分子量的超滤膜、表面活性剂浓度、膜操作压力、溶液pH和溶液中电解质等因素对该工艺的影响。结果表明,SDBS对双酚A有较好的去除效果,去除率在80%以上。在H+和Na+存在的条件下,双酚A的截留率增加,透过液中SDBS浓度降低。SDBS与非离子表面活性剂的复配可以提高双酚A截留率,降低透过液中SDBS的浓度,复配效果优劣顺序为Tween-80TritonX-100APG。 相似文献
994.
可用于水体污染控制的氨氮转化菌筛选及部分降解特性的实验研究 总被引:3,自引:0,他引:3
从南京禄口水产养殖基地淡水鱼塘取淤泥作为分离菌株的土源,采用选择性富集培养法,从中分离到能以硫酸铵为氮源的菌株7株,对7个菌株进行氨氮降解实验,它们氨氮转化率分别为14.8%、19.7%、53.4%、94.2%、29.1%、63.5%和41.7%,其中AN-4菌株的转化率最高且生长良好。通过AN-4菌株16S rRNA基因序列分析以及生理生化方法,鉴定此菌株为克雷伯氏菌属(Klebsiellasp.)。对菌株AN-4转化氨氮的特性及温度、pH值、氨氮初始浓度和菌株接种量对其氨氮转化率的影响研究,结果表明,菌株AN-4降解氨氮的最适条件为:温度为30℃和pH值为8.0;当氨氮初始浓度为30mg/L时,AN-4菌株在24 h内的氨氮降解率可达85%以上,且能耐受高达200 mg/L的氨氮浓度;AN-4活化菌液浓度为108cfu/mL,当接种量为3×106cfu/mL时,AN-4菌株在24 h内的氨氮降解率为87.75%。综合上述结果,符合淡水养殖水环境条件,说明AN-4菌株适合在水产养殖中应用,为将菌株AN-4应用于水产养殖环境修复提供了理论依据。 相似文献
995.
Nur Okur A. Levent Tuna Bülent Okur Hakan Altunlu H. Hüsnü Kayikçioğlu Hasan S. Civelek 《Environmental monitoring and assessment》2010,165(1-4):389-397
Efficacious botanical derivatives can provide an alternative to synthetic pesticides for organic farming systems. However, there is lack of information regarding the side effects of organic pesticides on key soil ecological processes. In this study, we investigated the effects of aqueous extracts from Urginea maritima and Euphorbia myrsinites exhibiting translaminar and systemic activity against pests on microbial biomass and enzymatic activities in soil. Two grams of plant material was extracted with 100 ml of water and then diluted 1:100, 2:100, and 4:100 with distilled water. Diluted plant extracts were applied around hypocotyl of tomato by soil drench. The effect of both plant extracts on microbial biomass C, amount of total N and organic C, and enzymatic activity in soil was significant. After the last application, the highest microbial biomass C was determined in the lowest U. maritima concentration (U 1:100). Soils treated with the highest concentration of U. maritima (U 4:100) had always lower SMBC content than control soil. All concentrations of E. myrsinites decreased microbial biomass C by 18% to 27% compared to the control. Total nitrogen and organic carbon decreased in soils without (control) and with treated U. maritima extract from first application to last application. Phosphatase, urease, and β-glucosidase activities were monitored in plant extract-treated soils. Except U. maritima 1:100 treatments of second and fourth applications, the other treatments of plant extracts negatively affected enzymatic activity in soil. U. maritima and E. myrsinites plant extracts exhibited different effects on soil microbial biomass and activity, probably because of their different chemical contents. 相似文献
996.
用基于Web的页面显示、业务逻辑、数据访问的B/S三层结构,在Microsoft SQL Server2000和Microsoft Visual Studio2005环境下设计开发了热带气旋灾害数据库信息管理系统。对不同类型的数据,采用多对多的数据映射关系,并以不同的方式进行不同的数据管理。为了将没有统一数据格式的热带气旋灾害信息源数据,能够正确地导入到SQL Server数据库中,编写了专门的C++程序对数据格式化,实现数据格式的BNF定义,同时,在系统的设计中,融入灾害评价方法模型供用户选择使用,并采取多项行之有效的措施以防止SQL注入式攻击。 相似文献
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Organochlorine pesticides (OCPs) such as DDT and DDE have been detected in the surface 0.2 m of Vertisols in the lower Namoi Valley of north western New South Wales, Australia even though they have not been applied to crops since 1982. However, their presence in the deeper soil horizons has not been investigated. The objective of this study was to determine if OCPs were present to a depth of 1.2 m in Vertisols under irrigated cotton farming systems in the lower Namoi Valley of New South Wales. Soil was sampled from the 0-1.2 m depths in three sites, viz. the Australian Cotton Research Institute, ACRI, near Narrabri (149°36′E, 30°12′S), and two cotton farms near Wee Waa (149°27′E, 30°13′S) and Merah North (149°18′E, 30°12′S) in northern New South Wales, Australia. The OCPs detected and their metabolites were α-endosulfan, β-endosulfan, endosulfan sulphate, DDD, DDE, DDT and endrin. The metabolite DDE, a breakdown product of DDT, was the most persistent OCP in all depths analysed. Endosulfan sulphate was the second most persistent followed by endrin > α-endosulfan > β-endosulfan > DDT and DDD. DDT was sprayed extensively in the lower Namoi Valley up to the early 1980s and may explain the persistence of DDE in the majority of soil samples. Dicofol and Dieldrin, two OCPs previously undocumented in Vertisols were also detected. The movement of OCPs into the subsoil of Vertisols may occur when irrigation or rain transports soil colloids and organic matter via preferential flow systems into the deeper layers of a soil profile. Persistence of OCPs was closely correlated to soil organic carbon concentrations. The persistence in soil of OCP’s applied to cotton crops grown more than two decades ago suggests that they could enter the food chain. Their presence at depths of 1.2 m suggests that they could move into groundwater that may eventually be used for domestic and stock consumption. 相似文献