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1.
根据对美国康涅狄格州诺沃克市的商业通讯股份有限公司 (BusinessCommunicationsCo .Inc .)的调查 ,目前美国生产的环境生物技术产品 (微生物、酶、微生物掺合剂、营养剂 )在全世界的销售额估计已达到 10 3 ,5 0 0 ,0 0 0美元。预计年平均增长率可达到 8 3 % ,这样到 2 0 0 6年 ,销售额有望达到 15 3 ,870 ,0 0 0美元。从在年平均增长速度中占 9 4%看来 ,微生物掺合剂在总销售额中有望达到最大增长量 ;营养剂在年平均增长速度中占8 8% ,增长速度和销售市场都仅次于微生物掺合剂 ,居于第二 ;由于酶和微生物产品呈…  相似文献   

2.
据报载 ,我国将加强对污水、工业废水、废气、垃圾无害化设备的研制生产 ,加快开发先进的生产工艺设备 ,尽快把环保产业建成具有良好经济效益和社会效益的新兴产业。目前我国的环保产业企业规模小 ,产品结构单一 ,技术水平低 ,远不能满足环保设施建设的需要。按目前的发展规划 ,到 2 0 0 0年 ,我国城市污水处理率应达到 2 0 %~ 30 % ,工业废水处理率达到 84 % ,城市污水再生利用率平均达到处理量的 10 %。到2 0 10年 ,缺水城市和地区以及中小城市污水再生利用率达到 30 %~ 4 0 %。到 2 0 0 0年 ,全国城市生活垃圾的处理率将提高到 80 %。…  相似文献   

3.
微生物协同降解深层石油污染土壤研究   总被引:1,自引:0,他引:1       下载免费PDF全文
为了消除土壤中石油类物质的污染,从现场油泥中分别筛选出高效降解菌铜绿假单胞和无色杆菌,对其独立使用和复配时对原油的降解规律进行了研究,探讨了复合菌体系加量、含水率、土壤含油量、氮磷营养比以及pH值、温度等对石油污染土壤降解率的影响。结果表明:复合微生物对土壤石油污染的降解率高于单独使用时的降解率,且当两者复合比例为1∶1,土壤含水率为25%时,9d降解率可达41.49%;温度为25℃、土壤含水率为25%、土壤pH值为7.5左右、菌液加量为5%、土壤含油率低于5%时,6d降解率可达到64.9%;保持土壤含水率为25%,pH值为7.5左右,保证充足的营养,含油率为2%的深层土壤54d降解率可达到43.2%。  相似文献   

4.
人工单面巢脾只有一个脾面 ,其巢房高 0 1mm~ 13 0mm ,房孔直径 4 5mm~ 7 0mm。人工单面巢脾固定在巢框内 ,巢框高度为 5mm~ 2 5mm。当它专用于产卵时 ,脾面覆盖隔王板 ,隔王板开有若干长度 2 0mm~ 40mm、宽度 3 8mm~ 4 15mm、厚度 0 1mm~ 10 0  相似文献   

5.
为验证菌株所产生的表面活性剂的乳化增效作用,以菌株Da-6产生的表面活性剂BH为研究对象,采用薄层层析(TLC)分析确定BH为脂肽类物质。对BH、鼠李糖脂、吐温80和SDS的临界胶束浓度(CMC)、乳化性能、排油能力和洗脱效果进行了对比实验;并研究温度、NaCl浓度以及pH值对BH表面活性的影响。实验结果表明:BH的CMC为25 mg/L;在72 h内乳化指数仍保持在70%,乳化性能较稳定;同一浓度下,排油直径最大为81.0 mm,均优于其他3种表面活性剂,排油能力较强;并且在12 h时达到最大洗脱率(90.23%),对油泥洗脱效果优异;在温度10~80℃、NaCl浓度0~16%、pH值4~13,BH仍保持较高表面活性,表面张力保持约26 mN/m,具有良好的稳定性。  相似文献   

6.
安徽生态省建设自2003年启动至今,在国家环保部的指导下,全省上下共同努力协调运转,生态省建设取得明显成效。截至2007年,安徽生态省建设第一阶段(2003~2007年)、第二阶段(2008~2015年)、第三阶段(2006~2020年)目标实现率分别达到75.9%、50.1%和39.5%,国民生产总值(GDP)增长近一倍;  相似文献   

7.
采用水溶液共聚合方法制备高分子脱水剂p (DMDAAC-co-IA-co-DMC),产物用傅里叶红外光谱(FTIR)、热失重(TGA)和差示扫描(DSC)进行了表征。用于污泥脱水试验,投加量为40mg/100g,污泥比阻降低率69. 9%、泥饼含水降低率11. 5%、滤液浊度去除率54. 0%;脱水剂与助剂硅藻土复配,硅藻土与脱水剂质量比为0. 1∶1,污泥比阻降低率73. 8%、滤饼含水降低率17. 4%、滤液浊度去除率77. 8%。对滤饼的电镜扫描(SEM)图像用分形理论的盒子计数法处理,非线性数学计算滤饼空隙分维数D_f与试验结果一致。  相似文献   

8.
厌氧氨氧化反应器的启动及运行   总被引:11,自引:0,他引:11  
采用污泥混合接种的方法 ,成功地启动了实验室规模的厌氧氨氧化反应器 ,启动后含氨模拟废水运行的进水氨浓度和进水亚硝基氮浓度均为 2 0mmol/L ,氨氮、亚硝基氮和总氮的容积负荷率为 10 6 9mmol/L .d、12 2 6mmol/L .d和 394 5 5mg/L .d ,氨氮、亚硝基氮和总氮的去除率保持在 90 %、99%和 95 %以上。对运行条件研究表明 ,厌氧氨氧化反应的最适pH为 7~ 7 5 ,最适温度约在30± 1℃。厌氧氨氧化随亚硝酸盐浓度的升高而下降 ,氨的厌氧转化随COD浓度的增加也呈抑制型曲线 ,当COD浓度为 80 0±5 0mg/L时 ,厌氧氨氧化速率达到最大。  相似文献   

9.
促进西葫芦座瓜的药剂按重量计其组份包括丁酯1 5%~ 1 8% ,赤霉素 0 36%~ 0 45% ,速克灵 0 0 2 5% ,其余为纯净水。本品克服了烂花烂果现象 ,提高了座瓜率 ,减少了畸形果 ,使瓜条生长快、色泽好 ,大大提高了商品瓜的产量和质量。 (CN 1 2 4 2 1 43A)促进西葫芦座瓜的  相似文献   

10.
本文采用材积源生物量法和土壤剖面分析方法,以四川彭州为典型案例,对栽植17年的人工柳杉、杉木、水杉、桦木、桤木、喜树林的碳聚积效应进行了研究.结果表明:不同树种的生物量积累规律为:柳杉>桦木>喜树>水杉>杉木>桤木,每公顷柳杉、桦木、喜树、水杉、杉木、桤木的生物量分别为172t、162t、157t、126t、124t、111t.柳杉的生物量比桦木、喜树、水杉、杉木、桤木增加5.81%、8.72%、26.7%、27.9%、35.5%;不同树种的林分碳贮量为柳杉>桦木>喜树>水杉>杉木>桤木,柳杉、桦木、喜树、水杉、杉木、桤木林分的碳贮量分别为86.0、81.0、7&5、63.0、62.0、55.5tC/hm2,表明柳杉比其它树种具有更强的生长能力和固碳能力;林下土壤的有机碳含量,在不同土层中的分布规律为:0~10cm>10~30cm>30~50cm>50~70cm,土壤有机碳集中分布于0~50cm土层内;不同树种林下土壤的碳贮量均高于同期的林分碳贮量,表明土壤碳库是林分碳库的补充和延续,且具有更大的固碳潜力.  相似文献   

11.
Fire and logging in nutrient-poor temperate forests with certain ericaceous understory plants may convert the forests into heaths. The process of disturbance-induced heath formation is documented by using examples ofCalluna in western Europe,Kalmia in Newfoundland, andGaultheria (salal) in coastal British Columbia. In a cool, temperate climate, rapid vegetative growth ofCalluna, Kalmia, and salal following disturbance results in increasing organic accumulation (paludification), nutrient sequestration, soil acidification, and allelochemicals. These are thought to be the main reasons to conifer regeneration failure in disturbed habitats. If continuation in forest is a land-use objective, then temperate forests with an ericaceous understory should not be logged unless effective silvicultural methods are devised to control the ericaceous plants and restore forest regeneration. Preharvest vegetation control may be considered as an option. Failure to control the understory plants may lead to a long-term vegetation shift, from forest to heathland, particularly in nutrient-poor sites. Successful methods of controllingKalmia andGaultheria, however, have yet to be developed. While theKalmia- andGaultheria- dominated heathlands are undesirable in Canada and the Pacific Northwest, a wide range ofCalluna heathlands of western Europe are being conserved as natural and seminatural vegetation.  相似文献   

12.
ABSTRACT: Sustained interest in and concern about the health status of the aquatic environment has resulted in extensive research focused on (1) effects of pollution on survival, growth, and reproduction of resource species at all life stages; (2) diseases of fish and shellfish, as they may be related to pollution and as they may serve as indicators of environmental stress; and (3) contaminant body burdens in fish and shellfish - their effects on the aquatic animals and their potential effects on humans. Effects, lethal and sublethal, of pollutants on life history stages of fish and shellfish have been documented, as have impacts on local stocks in badly degraded habitats, but as yet there has been no adequate quantitative demonstration of effects on entire aquatic species - probably because of the difficulty in sorting out relative effects of the many environmental factors that influence abundance. Sublethal effects, especially those that result in disease, have been examined intensively, and some diseases and disease syndromes have been associated statistically with pollution. Other pollution indicators (biochemical, physiological, genetic, behavioral, and ecological) have also received some attention, as have body burdens of contaminants in aquatic species. Research, especially that conducted during the past decade, has done much to clarify the many pathways and toxic effects of contaminants on aquatic animals, and has also helped to identify mechanisms for survival of fish and shellfish in the presence of environmental changes caused by human activities.  相似文献   

13.
Urban ecological systems: scientific foundations and a decade of progress   总被引:9,自引:0,他引:9  
Urban ecological studies, including focus on cities, suburbs, and exurbs, while having deep roots in the early to mid 20th century, have burgeoned in the last several decades. We use the state factor approach to highlight the role of important aspects of climate, substrate, organisms, relief, and time in differentiating urban from non-urban areas, and for determining heterogeneity within spatially extensive metropolitan areas. In addition to reviewing key findings relevant to each state factor, we note the emergence of tentative "urban syndromes" concerning soils, streams, wildlife and plants, and homogenization of certain ecosystem functions, such as soil organic carbon dynamics. We note the utility of the ecosystem approach, the human ecosystem framework, and watersheds as integrative tools to tie information about multiple state factors together. The organismal component of urban complexes includes the social organization of the human population, and we review key modes by which human populations within urban areas are differentiated, and how such differentiation affects environmentally relevant actions. Emerging syntheses in land change science and ecological urban design are also summarized. The multifaceted frameworks and the growing urban knowledge base do however identify some pressing research needs.  相似文献   

14.
Urban gardens are important sources of sustenance for communities with limited access to food. Hence, this study focuses on food production in gardens in the Toledo metropolitan area in Northwest Ohio. We administered surveys to 150 garden managers from November 2014 to February 2015 in our attempt to better understand how neighbourhood racial composition and poverty levels are related to staffing and voluntarism, food production and distribution, the development of infrastructure, and the adoption of sustainability practices in urban gardens. The results from 30 gardens are presented in this paper. We used Geographic Information Systems to map the gardens and overlay the map with 2010 census data so that we could conduct demographic analyses of the neighbourhoods in which the gardens were located. Though the gardens were small – two acres or less – up to 46 varieties of food were grown in a single garden. Gardens also operated on small budgets. Food from the gardens was gifted or shared with friends, family, and neighbourhood residents. Gardens in predominantly minority neighbourhoods tended to have fewer institutional partners, less garden infrastructure, and had adopted fewer sustainable practices than gardens in predominantly White neighbourhoods. Nonetheless, residents of predominantly minority and high-poverty neighbourhoods participated in garden activities and influenced garden operations. Volunteering and staffing were racialised and gendered.  相似文献   

15.
All major journalism ethical codes explicitly state that journalists should protect editorial copy from undue influence by outside sources. However, much of the previous research on agricultural information has concentrated on what information various media communicate (gatekeeping studies) or communication's role in increasing innovation adoption (diffusion studies). Few studies have concentrated specifically on organizational and structural constraints that might adversely affect agricultural journalists' ethical standards; those that have, focus largely on farm magazines. A study of newspaper reporters who cover agricultural news found that the most pressing ethical concern is the effect of advertiser (agri-business) pressure on editorial copy, and that their concerns in general parallel those of farm magazine writers and editors. The majority reported being in situations in which they might be exposed to advertiser pressure, including pressures to change or withhold editorial copy. Large minorities suggested that advertising pressures affect the overall environment in which agricultural journalists work, and more than one in ten said they allow advertiser pressures to influence editorial decisions. The newspaper reporters who cover agricultural beats showed slightly more resistance to advertiser pressure than did farm magazine editors in a parallel study.  相似文献   

16.
Mapped environmental classifications are defined using various procedures, but there has been little evaluation of the differences in their ability to discriminate variation in independent ecological characteristics. We tested the performance of environmental classifications of the streams and rivers of France that had been defined from the same environmental data using geographic regionalization and numerical classification of individual river valley segments. Test data comprised invertebrate assemblages, water chemistry, and hydrological indexes obtained from sites throughout France. Classification performance was measured by analysis of similarity (ANOSIM). Geometric regions defined by a regular grid and without regard to environmental variables and a posteriori classifications based on clustering the test datasets defined lower and upper bounds of performance for a given number of classes. Differences in classification performances were generally small. The ANOSIM statistics for the a posteriori classifications were around twice that of all environmental classifications, including geometrically defined regions. The hydro-ecoregions performed slightly better for the invertebrate data and the network classification performed slightly better for the chemistry and hydrological data. Our results indicate that environmental classifications that are defined using different procedures can be comparable in terms of their ability to discriminate variation of ecological characteristics and that alleged differences in performance arising from different classification procedures can be small relative to unexplained variation. We conclude that definition procedures might have little effect on the performance of large-scale environmental classifications and decisions over which procedures to use should be based primarily on pragmatic considerations.  相似文献   

17.
Collisions with deer and other large animals are increasing, and the resulting economic costs and risks to public safety have made mitigation measures a priority for both city and wildlife managers. We created landscape models to describe and predict deer-vehicle collision (DVCs) within the City of Edmonton, Alberta. Models based on roadside characteristics revealed that DVCs occurred frequently where roadside vegetation was both denser and more diverse, and that DVCs were more likely to occur when the groomed width of roadside right-of-ways was smaller. No DVCs occurred where the width of the vegetation-free or manicured roadside buffer was greater than 40 m. Landscape-based models showed that DVCs were more likely in more heterogeneous landscapes where road densities were lower and speed limits were higher, and where non-forested vegetation such as farmland was in closer proximity to larger tracts of forest. These models can help wildlife and transportation managers to identify locations of high collision frequency for mitigation. Modifying certain landscape and roadside habitats can be an effective way to reduce deer-vehicle collisions.  相似文献   

18.
Biodegradation of [A‐ring 14C] Estrone (E1), 17β‐estradiol (E2), and 17α‐ethinylestradiol (EE2) to 14CO2 was investigated under light and dark conditions in microcosms containing epilithon or sediment collected from Boulder Creek, Colorado. Mineralization of the estrogen A‐ring was observed in all sediment treatments, but not epilithon treatments. No difference in net mineralization between light and dark treatments was observed for 14C‐E2. Net mineralization of 14C‐E1 and 14C‐EE2 was enhanced in light treatments. Extents of 14CO2 accumulation and rates of mineralization were significantly greater for E2 than E1 under dark conditions, but were comparable under light conditions. These results indicate substantial differences in the uptake and metabolism of E1 and E2 in the environment and suggest biorecalcitrance of E1 relative to E2 in light‐limited environments. The extent of 14CO2 accumulation and rate of mineralization for EE2 in dark treatments were less than half of that observed for E2 and generally lower than for E1, consistent with previous reports of EE2 biorecalcitrance. However, 14CO2 accumulation and rates of mineralization were comparable for EE2, E2, and E1 under light conditions. These results indicate photoactivation and/or phototransformation/photodegradation processes can substantially enhance heterotrophic biodegradation of estrogens in sunlit environments and may play an important role in estrogen transport and attenuation.  相似文献   

19.
Abstract

Sustainable ecosystems can be designed to eliminate environmental toxins and reduce pathogen loads through the direct and indirect consequences of plant and microbial activities. We present an approach to the bioremediation of disturbed environments, focusing on petroleum hydrocarbon (PHC) contaminants. Treatment consists of incorporating a plant-based amendment to enhance ecosystem productivity and physiochemical degradation followed by the establishment of plants to serve as oxidizers and foundations for microbial communities. Promising amendments for widespread use are entire plants of the water fern Azolla and seed meal of Brassica napus (rapeseed). An inexpensive byproduct from the manufacture of biodiesel and lubricants, rapeseed meal is high in nitrogen (6% wt/wt), stimulates >100-fold increases in populations of resident Streptomyces species, and suppresses fungal infection of roots subsequently cultivated in the amended soil. Synergistic enzymatic and chemical activities of plant and microbial metabolism in root zones transform and degrade soil contaminants. Emphasis is given to mechanisms that enable PHC functionalization via reactive molecular species.  相似文献   

20.
Zimbabwean provincial plans were instituted to help in the achievement of the national goal of the creation of an egalitarian, socialist and integrated society. The national goal itself was adopted as an antithesis to the dualist society characterised by spatial, economic, social, politican and technological inequalities that Zimbabwe inherited from colonialism. This meant that provincial plans had to play both a functional (or growth allocating/distribution) and a territorial (or redistribution) role.

This paper reviews their role in achieving the national goal by examining their functions, content, structure and methodology. The paper concludes that because of their nature, provincial plans are not suitable tools for the achievement of the national goal.  相似文献   


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