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161.
Jančula D  Maršálek B 《Chemosphere》2011,85(9):1415-1422
Cyanobacteria proliferation is among the most threatening consequences of freshwater pollution. Health risks from human and other-organism exposure to cyanobacteria have led to an effort to find practical methods for cyanobacterial water-bloom reduction. Hence, methods and techniques have been developed in order to reduce the amount of phosphorus or to decrease the abundance of nuisance phytoplankton species directly in the water bodies (in-lake measures). Although these “acute” methods do not solve the problem of catchment area eutrophication, they are cheaper, easier to manage, and for some areas they are the only way to protect human and environmental health against massive cyanobacterial proliferation. This review summarizes the extent of knowledge and published data about the management using metals (Al, Fe, Cu, Ag, Ca), photosensitizers (hydrogen peroxide, phthalocyanines, TiO2), herbicides and chemicals derived from natural compounds as fast and efficient removal agents of cyanobacteria. This review concludes that some compounds, when non-persistent and ecotoxicologically acceptable may help to manage cyanobacterial blooms in an efficient way compared to previous methods (e.g. copper sulfate).  相似文献   
162.
Multi-year inventories of carbonaceous aerosol emissions from biomass open burning at a high spatial resolution of 0.5° × 0.5° have been constructed in China using GIS methodology for the period 1990-2005. Black carbon (BC) emissions have increased by 383.03% at an annual average rate of 25.54% from 14.05 Gg in 1990 to 67.87 Gg in 2005; while organic carbon (OC) emissions have increased by 365.43% from 57.37 Gg in 1990 to 267.00 Gg in 2005. Through the estimation period, OC/BC ratio for biomass burning was averagely 4.09, suggesting that it was not the preferred control source from a climatic perspective. Spatial distribution of BC and OC emissions were similar, mainly concentrated in three northeastern provinces, central provinces of Shandong, Jiangsu, Anhui and Henan, and southern provinces of Guangxi, Guangdong, Hunan and Sichuan basin, covering 24.89% of China’s territory, but were responsible for 63.38% and 67.55% of national BC and OC emissions, respectively.  相似文献   
163.
This study takes the perspective of emerging economies as an independent group to answer the question of how to reconcile food supply and bioenergy feedstock provision, a critical topic in bioenergy research. While much of the literature has covered this issue, the role of emerging economies has rarely been explored. Due to their transitional status in the world economy, solutions from this group can facilitate the diffusion of modern bioenergy from industrialized countries to least developed ones. This paper uses Jiangsu Province in China as a case study to analyze its local practice on the reconciliation between food and bioenergy. Local experience reveals that the key is the use of cellulosic biomass, whose sources are straws of food crops on arable lands and energy crops on reclaimed mudflats. To ensure a sustainable provision of cellulosic biomass, it is necessary to involve the entire bioenergy supply chain consisting of smallholder farmers, haulers and bioenergy plant operators. For the management of the supply chain, we compare two options, “Multiple to Multiple” and “Multiple to One”, where the second option is more adequate to shape a long-term stable relationship between biomass suppliers and consumers and thus facilitate the introduction of energy crops.  相似文献   
164.
对辽河盘锦段浮游藻类的种类、种群密度和生物量进行了调查和分析,并采用生物多样性指数法对水质进行了评价。评价结果表明,辽河盘锦段水质总体属轻度污染,并根据当地情况提出了保护水质的建议。  相似文献   
165.
Oil pollution is causing deleterious damage to aquatic ecosystems and human health. The utilization of agricultural waste such as corn stalk (CS) to produce biosorbents has been considered an ecofriendly and efficient approach for removing oil. However, most previous studies focused on the modification of the whole CS, which is inefficient due to the heterogeneity of CS. In this study, corn stalk pith (CP), which has excellent amphipathic characteristics, was selected to prepare a high-efficienc...  相似文献   
166.
Physical characteristics and quantitative elemental composition of PM and residual ash produced from sugarcane leaves (SCL) combustion were investigated using TEM-EDS compared with forest leaves (FRL). SEM-EDS was used to analyze the microstructure and chemical composition of biomass raw leaves and PM. XRD analysis was also performed to investigate the characterization of the crystalline nanostructure, structure of PM, and residual ash compared to the TEM image processing method. The oxidation kinetics of biomass raw materials, PM, and residual ash were investigated by TGA. The morphology of fine and ultrafine agglomerate structure of SCL soot and residual ash are not significantly different from the FRL soot and residual ash. The average diameter sizes of single primary nanoparticles of SCL and FRL soot are approximately 37 nm and 35 nm, while the sizes of residual ash are about 18 nm and 22 nm, respectively. The single primary nanoparticles of soot are mainly composed of curve line crystallites of carbon fringes, while residual ash is composed of straight-line lattice fringes. The average fringe lengths of SCL and FRL soot are about 1.25 nm and 1.04 nm from the outer shell and 0.89 nm and 0.74 nm from the inner core. The interlayer spacing of curve line carbon fringes of SCL and FRL soot is approximately 0.359 nm and 0.362 nm by the TEM image analysis and it was matched with XRD analysis. The biomass PMs are mainly composed of soot, Si, Ca, and K compounds: SiO2, CaCO3, and KCl.  相似文献   
167.
生物质能是当前能源和生态环境领域研究的热点。分析和研究,指出了生物质能在国内外的发展现状和趋势。全、实现可持续发展意义重大。本文对生物质能的资源分类和利用方式进行了明确了开发利用生物质能源,对保障国家能源安  相似文献   
168.
In this paper we present, for the first time, data on the combustion of Miscanthus × Giganteus straw and pellets. We found that the heating value of Miscanthus is 17.744 MJ/kg. The gaseous emission indices of SO2, NO x and total organic carbon (TOC) in the exhaust are reported and compared with the European standards for biomass boilers. On the basis of our results, it is possible to evaluate a net energy yield between 152 and 326 MJ/hectare/year for the cultivation of Miscanthus with an energy balance estimated to be in the range of 7.7–15.4. According to the presented results, it seems reasonable to consider Miscanthus as a promising candidate as alternative fuel.  相似文献   
169.
根据2006年10月野外调查数据及1998年的LANDSAT 5卫星影像解译的辽宁省植被类型数据,以辽宁省滨海公路沿线植被生态系统为研究对象,运用ARCVIEW3.3、ARCGIS9.0和FRAGSTATS3.3软件研究辽宁省滨海公路建设对沿线生态系统结构的影响,结果表明:①辽宁省滨海公路跨越2个纬度和5个经度,沿线主要植被类型以湿地生态系统和农业生态系统为主。②辽宁省滨海公路的建设对生态系统产生直接的切割,使景观更加破碎。③辽宁省滨海公路的建设直接破坏沿线植被生态系统(主要为50m缓冲区内),损失总净初级生产量为25778.39 t/a,损失总生物量199274.2~284380.6t/a。建议采取一些必要的环境保护及生态恢复性措施。  相似文献   
170.
研究了低温(4~8℃)沸石一蛭石曝气生物滤池处理污水厂尾水稳态运行时生物膜形态、生物量和微生物活性变化特征,分析了反应器内生物量和微生物活性的空间变化规律。结果表明,曝气生物滤池的生物膜形态、生物量及微生物活性有沿水流方向渐变的特点,生物量及微生物活性沿水流方向呈现递减的趋势.且生物量、微生物活性呈正相关。  相似文献   
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