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1.
资源化、无害化利用水葫芦是治理其泛滥的有效途径。利用水葫芦去除水体中的营养物并利用其生物质生产沼气在技术上具有可行性,但是其环境经济效益尚不明确。以滇池为例,针对富营养化水体的水葫芦控制进行了成本收益分析。与将水葫芦打捞后填埋处理相比,将所打捞的水葫芦用于生产沼气具有经济可行性和能量效率。与现行的填埋处理法相比,实施沼气项目不但同样能控制水葫芦泛滥,而且能生产能源。此外,填埋水葫芦会释放甲烷这一环境问题值得重视,利用水葫芦生产沼气可以减少温室气体的排放,但减排的价值取决于沼气厂的生产规模。由于将水葫芦填埋和用于生产沼气都能去除水体中的营养物,只有当沼气厂的水葫芦处理量大于当前的填埋量时,沼气项目才具有额外的水质改良价值。在中国关于水污染控制、可再生能源发展和节能减排等政策的背景下,利用水葫芦生产沼气是一种潜在的政策响应  相似文献   

2.
水葫芦资源化处置与综合利用研究评述   总被引:7,自引:0,他引:7  
水葫芦(凤眼莲)是一种源自南美的浮水植物。由于人为引入,水葫芦已经遍布整个热带、亚热带地区,带来了诸如鱼类减产、影响捕鱼、堵塞航道等问题。水葫芦木质素、纤维素含量高,含水率大,因此处置处理困难;同时由于水葫芦种子存活时间长、繁殖速度快,所以水葫芦的控制至今仍是个难题。简要阐述了水葫芦的生物学特性及现有的控制方法;对水葫芦的化学组成研究进行了总结;将其资源化处置方式归纳为制备燃料(固体燃料、液体燃料及气体燃料)、饲料(干饲料、青贮饲料)和肥料(有机肥、绿肥)3种方式,在对各项技术分别评述的基础上进行了比较。提出制备沼气燃料和有机肥是水葫芦目前较有前景的利用方式。但对于农村地区的水葫芦处置来说,简易的堆肥和绿肥还田是更为合适的处置方式。  相似文献   

3.
构建湿地是 2 0世纪 70年代才蓬勃兴起的一种处理污水的方式 ,由于其造价和运行费用低 ,净化效果稳定 ,越来越引起各国的兴趣和高度重视。现已广泛应用于城市生活污水、工业污水和农业污水的控制 ,有着十分广阔的应用前景。虽然关于构建湿地净化污水的研究已有不少报道 ,但关于湿地基质中的微生物类群和基质酶在污水净化中的作用仍不清楚。通过对生长在复合垂直流构建湿地和天然环境条件下菰和石菖蒲根区微生物类群数量及其根区基质酶活性的测定发现 :同种植物在复合垂直流构建湿地根区微生物的数量比天然条件下的要高 ,特别是硝化细菌和反硝化细菌的数量 ,最高可达 3个数量级以上 ;同时复合垂直流构建湿地中不同植物根区的酶活性有较大差别 ,这为研究复合垂直流构建湿地净化污水的机理和以酶活性强弱作为净化效果的评价指标提供了科学资料 ,为进一步研究提供了一条新思路  相似文献   

4.
Cassava tubers produced under hot, dry and monsoon governed climate in the Salem region, Tamil Nadu, South India, consume together with the about 1000 starch extracting industries daily, 9 millions of litres of groundwater which have to be pumped from a depth of 80 m below ground level. Because of water shortage, adjacent fields are irrigated with organically highly enriched sago factories wastewater and the land becomes unproductive. One-third of the wastewater is presently channelled through a few installed biogas plants with a purification efficiency, biological oxygen demand, of only around 30%. Microbiologically and chemically analysed in- and effluents of biogas plants exhibited nutrient contents sufficient to maintain a rice crop and significantly higher population densities of fermenting bacteria and methanogenic archaea, despite C/N ratio of about 250. CO2 and CH4 emissions from aerobic and anaerobic incubated sago factory biogas plants in- and effluents indicated that the present purification efficiency of 30% can be further enhanced. This investigation has given clues for designing a purification system that connects the already installed biogas plants with a well-aerated, hydro-cultured, constructed wetland and a Stirling motor device for electric power gains and heat distillation, for enabling reuse of process water and saving groundwater.  相似文献   

5.
Farmers in Sahelian countries are confronted with a variety of soil fertility and management problems. During the last two decades, NGOs have worked with farmers and research institutions to develop and test practices that will increase food production, while at the same time enhance the natural resource base.Since 1987, The Rodale Institute (RI) has worked closely with farmers' associations and government institutions to promote regenerative agriculture-farming systems that prioritize the use of local resources while improving them as they are used to grow food, using agro-ecological methods. The Senegalese Agricultural Research Institute has collaborated in this program as a partner of RI. The Senegal Regenerative Agriculture Resource Center model has been applied as a new and viable approach that builds on traditional knowledge and farmer-to-farmer exchange.Research results on soil conservation and improvement have shown that fields spread with amended animal manure or compost yield greater harvests than fields farmed with traditional methods.  相似文献   

6.
Botswana is a rapidly developing country in southern Africa. Over the last three decades, diamond mining and tourism have provided double-digit rates of economic growth. Yet most of Botswana’s land is in the Kalahari desert where the climate is subject to sustained periods of severe drought. In this environment, water resources are the most crucial of all environmental resources. Water use directly affects economic development because water utilization impacts all the major national economic sectors. A sustainable water use resource management plan must stretch several decades into the future to assure the availability of adequate supplies of water to future generations while not compromising the ability of the current generation to reasonable rates of economic development. Yet thinking about sustainability is present in Botswana water policy mostly only in rhetoric. A series of cultural traditions and political constraints, coupled with bureaucratic managerial weaknesses, serve to maintain a system of water allocation that is unsustainable in the long run and inefficient in the short-term. Unless sustainable water use patterns are adopted, the results for the short-term, as well as the long-term, will be devastating. Drawing on data obtained through a series of interviews with government officials, leaders of non-governmental organizations (NGOs), and water resource researchers, this paper explores water policy in Botswana within the larger context of sustainable natural resource management practice and the pressures of economic development. This research was partially funded under U.S. Department of State, College and University Affiliations Grant # ASCS-1095.  相似文献   

7.
The Brazilian Amazon has about 69 % of available freshwater in Brazil, an amount that ends up creating the illusion that no lack of water and not lacking in the region, the large supply of this resource becomes a problem when it comes to the Management and Planning Water Resources in the Amazon, according to the wasteful use and lack of maintenance of stocks, compounded by the release of untreated wastewater. Speaking of water conservation programs in the Amazon a few decades ago and still today, with less intensity, is somewhat strange, given the large amount of water available and the culture of abundance. Thus, this research discusses the importance of the use of rainwater for non-potable purposes, since the potential for exploitation, throughout the year, due to this high rainfall in the Amazon region, ranging from, on average, 119.6 mm in months from November to 441.6 mm in March. The methods used for sizing of the reservoir were the Rippl and interactive, and economic viability checking done by the methods of net present value and discounted payback. As a result, there was a volume exceeding 1,000 m³ obtained by the method of Rippl, while the interactive method was a maximum of 75 m³. The economic viability presented fragile as a function of time to return exceeds the useful life of the utilization system for rainwater.  相似文献   

8.
为全面研究生态文明背景下岷沱江流域水环境治理成效,该研究从水生态保护与修复、水污染治理与控制、水资源开发利用和社会经济承载4个维度构建评价指标体系,先采用灰色关联分析法和均方差决策法建立组合权重,再通过加权综合指数法和理想解模型对2011~2017年岷沱江流域10个主要地级市的水环境治理绩效进行动态评价,最后利用ArcGIS10.5软件进行评价结果的时空分异性的可视化。研究表明:在水环境综合管理下,岷沱江流域水环境治理绩效水平呈上升的趋势。空间分布上,虽岷沱江流域上、中、下游的水环境治理绩效整体水平差异性逐渐缩小,但流域中各地级市在水污染治理与水资源开发利用上存在明显的差异性,今后岷沱江流域应重点控制水污染和优化水资源配置,统筹流域可持续发展的水环境管理。  相似文献   

9.
正确评价区域水资源可持续利用,对区域社会、经济的可持续发展以及生态环境的良性循环都具有重要意义,而区域水资源可持续利用指标体系及评价方法研究是水资源可持续利用研究的基础。借鉴现有评价指标体系的优点,并充分考虑现有评价指标体系所忽略的某些环境因素对水资源可持续利用的影响,针对区域社会-经济-环境复合系统的特点,提出了由区域水资源条件、水资源开发利用程度、区域水资源与社会协调程度、区域水资源与环境协调程度4个子系统及评价指标组成的区域水资源可持续利用评价指标体系。根据水资源系统的随机性、模糊性等特性以及系统评价的公正、客观要求,为规避评价方法的主观性与客观性影响,分别应用主观性较强的模糊层次分析法(FAHP)与客观性较强的投影寻踪模型(PP)对区域水资源可持续利用水平进行评价,并将两种方法的评价结果进行加权求和以实现优势互补,以此建立了区域水资源评价的一种新模型(FAHP PP),然后通过以上海市1998~2007年水资源可持续利用情况为例对该评价指标体系的合理性及方法的有效性进行了说明.  相似文献   

10.
跨国界河流、跨流域调水与我国南水北调的基本问题   总被引:18,自引:1,他引:17  
跨国界河流常是当今国与国水资源矛盾与冲突的发源地。在水资源空间分布不均衡背景下,跨流域调水是解决地区性水资源短缺的有效途径之一;然而,它同时也导致一系列社会经济与资源环境等问题。本文论述了主要跨国界流域中有关国家围绕水资源展开的矛盾与冲突,谈判与妥协。  相似文献   

11.
为了找出外海规模化控养水葫芦(E.crassipes)局部死亡的原因,于2013年8月对控养水域水葫芦空白对照区、健壮区、轻度枯死区以及重度枯死区的水质理化性质、蓝藻生物量及水生植物病理学等方面进行了比较研究。结果表明:轻度和重度枯死区蓝藻生物量高达(4.21±0.49)×109 cells/L和(757.00±19.00)×109 cells/L,均显著高于空白区和健壮区(0.14±0.09)×109 cells/L和(1.46±0.11)×109 cells/L(P0.05);NH+4-N浓度为11.44±0.02mg/L和369.87±15.37mg/L,均显著高于空白区和健壮区0.32±0.01mg/L和0.34±0.01mg/L(P0.05);轻度和重度枯死区溶氧仅1.40±0.13mg/L和0.30±0.04mg/L显著低于空白区和健壮区的7.70±0.83mg/L和6.80±0.97mg/L(P0.05);枯死区水体氧化还原电位(Eh)较低,重度死亡区水体Eh为-279.70±29.70mv显著低于其他3处水域。并且,通过对枯死水葫芦常规病理学检测,并未发现病变迹象。由此推断:水葫芦死亡原因可能主要由下风向种养区蓝藻过量堆积死亡,致使水质恶化,水体严重缺氧,进而引起水体NH+4-N浓度过高,最终导致水葫芦死亡。这为今后种养水葫芦进行水体生态修复理论研究与实践运用提供借鉴和参考,也为利用水葫芦作为蓝藻拦截带,在水葫芦影响下的湖泊营养物质迁移与氮、磷、碳循环动力学提出了新的研究内容。  相似文献   

12.
A variety of methods have been proposed, developed, and evaluated for detecting viruses, especially human enteric viruses, in water, wastewater, and other environmental samples, and continued developments and improvements have led to simpler and more reliable methodology. However, the use of currently available methods is still limited primarily to special circumstances, such as investigation of waterborne disease outbreaks, research studies on virus reductions by water and wastewater treatment processes and systems, especially reuse systems, and research monitoring and surveying of natural and treated waters. Widespread and routine virus monitoring is still not possible due to technical limitations and deficiencies of present detection methods and their relatively high cost. Although continued development of new methods and further improvement of existing methods is desirable, it is perhaps more important that current methods be systematically evaluated in carefully designed collaborative (round-robin) studies and quality assurance tests. Until virus detection methods are further improved and systematically evaluated, the establishment of virus standards for such materials as water and edible shellfish requiring routine monitoring appears to be unjustified.  相似文献   

13.
灰色协调度模型在产业用水系统分析中的应用   总被引:1,自引:0,他引:1  
揭示产业用水系统的时空动态发展规律,探讨其内部的协调关系,是开展节水型社会建设规划,实现水资源可持续利用的关键。然而,目前对产业用水系统的协调性分析还缺乏较为有效的理论和方法。以往在利用协调度模型进行用水系统有序度研究时,通常采用两段叙述的线性分段函数表示,较不适用于描述产业用水系统内部要素的非线性结构。因此,针对产业用水系统的特性,利用灰关联原理建立有序度函数,以建立更适于用水系统分析的灰色协调度模型。利用该模型对上海市1997~2005年产业用水系统进行实证研究,结果显示:上海市产业用水系统基本有序,发展比较协调,其用水综合效益较大,但距离最优状态尚有潜力可挖;其中,农业用水子系统的发展较为欠缺,在未来用水规划中应予以重视。  相似文献   

14.
正确评价区域水资源可持续利用,对区域社会、经济的可持续发展以及生态环境的良性循环都具有重要意义,而区域水资源可持续利用指标体系及评价方法研究是水资源可持续利用研究的基础。借鉴现有评价指标体系的优点,并充分考虑现有评价指标体系所忽略的某些环境因素对水资源可持续利用的影响,针对区域社会-经济-环境复合系统的特点,提出了由区域水资源条件、水资源开发利用程度、区域水资源与社会协调程度、区域水资源与环境协调程度4个子系统及评价指标组成的区域水资源可持续利用评价指标体系。根据水资源系统的随机性、模糊性等特性以及系统评价的公正、客观要求,为规避评价方法的主观性与客观性影响,分别应用主观性较强的模糊层次分析法(FAHP)与客观性较强的投影寻踪模型(PP)对区域水资源可持续利用水平进行评价,并将两种方法的评价结果进行加权求和以实现优势互补,以此建立了区域水资源评价的一种新模型(FAHP PP),然后通过以上海市1998~2007年水资源可持续利用情况为例对该评价指标体系的合理性及方法的有效性进行了说明.  相似文献   

15.
The suitability of olive mill wastewater (OMW) for composting was studied by the addition of this liquid waste to a mixture of cotton gin waste and sewage sludge, and its composting was compared with that of another pile of similar composition, but without olive mill wastewater. Both piles were composted by the Rutgers static pile system in a pilot plant. To study the effects of both composts on plant yield and soil properties, a plot experiment was carried out with Swiss chard (Beta vulgaris L. var. cicla). Five treatments were applied: mineral fertiliser and two doses (30 and 60 tons ha(-1)) of both composts. The olive mill wastewater addition produced a compost with lower organic matter and nitrate concentrations, higher electrical conductivity, and a stabilised and humified organic matter similar to that of the compost produced without olive mill wastewater. The olive mill wastewater compost application to soil did not injure plants, producing a similar plant yield to both compost without olive mill wastewater and inorganic fertiliser. Also, the accumulation of potentially toxic heavy metals in plants cultivated with organic or mineral fertilisers did not reveal significant differences. The olive mill wastewater compost application to soil also improved the chemical and physicochemical properties of the soil.  相似文献   

16.
随着滇池治理的进展,在今后一个时期内,恢复滇池饮用水环境功能,成为滇池治理的首要目标和任务。围绕滇池流域水资源供求平衡,采用水资源全要素配置框架下的三次平衡分析理论,从整体上分析了滇池流域水资源供求平衡关系及存在的主要问题,提出了以需求为导向,建立滇池流域水资源综合平衡管理目标和措施。分析表明:在滇池治理的基础上,通过建立滇池流域水资源综合平衡管理体系,落实管理措施,从总量平衡的理论上能够充分发挥引水工程的作用,恢复滇池饮用水环境功能,实现水量、水质供求的综合平衡。建议进一步开展量化分析和模拟实验研究,为在滇池流域实施综合平衡管理提供可靠依据和建议  相似文献   

17.
This article is a case study to compare the economic viabilities of biogas generation and compost projects in a palm oil mill in Malaysia with and without clean development mechanism (CDM). Biogas is captured from anaerobic ponds or digester tanks treating palm oil mill effluent (POME) and converted to green renewable electricity for grid connection, while compost is produced from the shredded empty fruit bunch and raw untreated POME. The both technologies were compared by considering the changes of the materials flow and energy balances. A palm oil mill with a capacity of 54?t fresh fruit bunch per hour has the potential to produce either 6.9?GWh of electricity from biogas or fertilizer equivalent to 488?t of nitrogen, 76?t of phosphorus and 1,065?t of potassium per year. The economic analysis for 10?years project term analysis indicated that CDM gave a significant impact and ensured economic viability for both projects with 25?% of internal rate of return (IRR), RM 12.39 million of net present value (NPV) and 3.5?years of payback period (PBP) for biogas project, whereas 31?% of IRR, RM 10.87 million of NPV and 2.9?years of PBP for compost project, respectively. In addition, sensitivity analysis indicated that the profitability of both projects will vary depending on the economic situation, such as electricity price which is based on the government policy, whereas compost price that depend on fertilizer market price with 43?% NPV change in 20?% range of fertilizer value.  相似文献   

18.
运用Romer的内生经济增长模型和全要素贡献模型,对1988~2009年中部地区经济和自然资源进行面板数据分析,计算出各省自然资源要素和其他要素对经济增长的贡献值。结论显示:中部地区经济增长中自然资源生产率呈现出“能源主打,水土作衬;北煤南水,地异明显”的结构、空间特性;其他生产性要素中,资本、劳动力资源生产率对经济增长的贡献不相上下;而全要素生产率除湖北外都不及全国平均水平,中部6省的科技创新能力亟待提高。针对中部经济资源现状提出相应政策建议,认为中部地区应该在资源利用效率的提高、自主研发能力的推崇、各项人才的培养和产业优化的推动方面多做工作,推进低碳经济发展  相似文献   

19.
沼气农业复合生态系统能值分析   总被引:1,自引:0,他引:1  
以沼气为纽带的农业综合利用系统对农村和偏远地区可持续发展具有重要意义。本文基于能值流图和指标体系,构建了沼气农业复合生态系统的综合评价框架,并以国家沼气农业示范区广西恭城县为案例,分析养殖-沼气-种植"三位一体"典型沼气农业复合系统的能值投入产出量及其结构,利用能值系统结构功能指标对该系统进行经济生态多元分析,评估其投资率、产出率、环境压力以及可持续性等系统综合表现,并与国内外其他农业系统进行比较分析。系统投入结果表明,恭城县沼气农业复合系统总投入中人类经济反馈在系统中所占比例最大,可更新环境资源次之,其中又以肥料、农药和劳工与管理的投入最大;系统产出表明,目前仍以种植业和养殖业为主导,水产业相对薄弱,而新兴的沼气产业因其低耗高产的特点,发展势头良好;而能值系统结构功能指标表明该农业系统整体具有环境负荷低、产出效率高、可持续性强等优势。依照能值分析各项结果,本文对沼气农业系统优化配置和进一步推广应用提出了参考建议。  相似文献   

20.
Among all emerging substances in water, pharmaceutical products (PPs) and residues are a lot of concern. These last two years, the number of studies has increased drastically, however much less for water resources and drinking water than for wastewater. This literature review based on recent works, deals with water resources (surface or groundwater), focusing on characteristics, occurrence and fate of numerous PPs studied, and drinking water including water quality. Through this review, it appears that the pharmaceutical risk must be considered even in drinking water where concentrations are very low. Moreover, there is a lack of research for by-products (metabolites and transformation products) characterization, occurrence and fate in all water types and especially in drinking water.  相似文献   

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