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191.
Karen Mancl 《Journal of the American Water Resources Association》1989,25(5):985-989
ABSTRACT: Providing adequate wastewater treatment facilities for the citizens in small rural communities in the United States can cost millions of dollars. An educational program has been developed and conducted in Ohio to teach local officials about wastewater treatment alternatives. The five-session workshop covers wastewater treatment principles, needs assessment, system management, and resource gathering. The knowledge and skills gained by the 96 community leaders who participated in six workshops were measured using a pretest/pest test and surveys conducted during the workshops. From 25 percent to 100 percent of the participants increased their knowledge of treatment systems, alternatives, and relative costs. From 23 percent to 84 percent applied new skills, such as conducting a sanitary survey or examining treatment systems. The pretest also revealed previous knowledge of the participants in the areas of system maintenance and consultant qualifications. 相似文献
192.
A variety of species was observed as either visitors, permanent, or summer residents on surface mines with different ecological adaptations. Passerine species were the most prevalent of the 25 families represented. Bird communities as well as individual species were correlated with the structure and species of vegetation on the mines. The composition of the bird communities changed in response to successional vegetation stages from grassland to forest communities. 相似文献
193.
Understanding Stream Geomorphic State in Relation to Ecological Integrity: Evidence Using Habitat Assessments and Macroinvertebrates 总被引:2,自引:0,他引:2
Scientists have long assumed that the physical structure and condition of stream and river channels have pervasive effects on biological communities and processes, but specific tests are few. To investigate the influence of the stream-reach geomorphic state on in-stream habitat and aquatic macroinvertebrate communities, we compared measures of habitat conditions and macroinvertebrate community composition between stable and unstable stream reaches in a paired-study design. We also explored potential associations between these ecological measures and individual geomorphic characteristics and channel adjustment processes (degradation, aggradation, overwidening, and change in planform). We found that habitat quality and heterogeneity were closely tied to stream stability, with geomorphically stable reaches supporting better habitat than unstable reaches. Geomorphic and habitat assessment scores were highly correlated (r = 0.624, P < 0.006, n = 18). Stable reaches did not support significantly greater macroinvertebrate densities than unstable reaches (t = −0.415, P > 0.689, df = 8). However, the percent of the macroinvertebrate community in the Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa was significantly correlated with the overall habitat assessment scores as well as with individual measures of geomorphic condition and habitat quality. While there is a clear need for more work in classifying and quantifying the responses of aquatic and aquatic-dependent biota to various geomorphic states and processes, this study provides solid preliminary evidence that macroinvertebrate communities are affected by the geomorphic condition of the stream reaches they inhabit and that geomorphic assessment approaches can be used as a tool for evaluating ecological integrity. 相似文献
194.
Effects of changing environments of riverside mangroves, coastal land uses, and water quality on fish communities were studied in Bangphra and Thaprik creeks, Trat Bay, Thailand. Regression analysis revealed that fish species richness in the wet season had a negative relationship with water transparency, nitrate, and phosphate and a positive relationship with zooplankton. In the dry season, species richness had a negative relationship with nitrate and phosphate and a positive relationship with salinity, pH, and zooplankton. Abundances and species richness of fish declined over distance from downstream to upstream in both creeks. Riparian mangroves and water quality also declined with distance upstream in both creeks. Results from one-way analysis of variance and Tukey’s HSD test revealed that the highest zooplankton volume with the lowest amounts of nitrate and phosphate were observed at the downstream station in both creeks in each season. Low zooplankton volume with high amounts of nitrate and phosphate were found at the midstream and upstream stations of the creeks. The midstream and upstream stations of Bangphra Creek had low to moderate abundance of mangroves along the riversides, whereas shrimp farms were mainly found along the riversides at the midstream and upstream stations of Thaprik Creek. Correlation analysis results of land-use types and the significant habitat factors were discussed. This study found that mangrove degradation, shrimp farming, and residential and agricultural areas altered water quality and the health of fish habitats, causing the decreases in fish abundance and species richness. 相似文献
195.
彭玉丹 《中国环境管理干部学院学报》2005,15(2):70-72,89
在简单介绍当前秦皇岛市部分社区存在的环境问题及环境管理方面出现的问题的基础上,分析其产生原因,并结合环境管理相关法律、法规、政策和制度,从多方面提出解决的对策及建议. 相似文献
196.
我国厨余垃圾产量巨大,含固率在25%左右,不适于填埋,厨余垃圾处理亟待寻找其他出路.本研究在中温((37±1)℃)条件下,构建了垂直流厌氧处理系统处理高含固厨余垃圾,并对其启动阶段运行效能及启动后系统微生物群落结构进行了分析.稳定运行后,系统容积负荷为9.79 g·L-1·d-1,挥发性固体(VS)降解率为80.57%±4.10%,比产气率(SBP)和比甲烷产率(SMP)分别为(0.748±0.078)L·g-1·d-1和(0.405±0.052)L·g-1·d-1,系统缓冲能力强,具有良好的产气能力,不存在酸抑制和氨抑制的情况.对不同位置的微生物群落结构进行分析,细菌在反应器主体的优势菌为Chloroflexi菌门中的Levilinea菌属,参与碳水化合物水解酸化的细菌分布较广;古菌的优势菌属则为Methanothrix、Methanobacterium和Methanolinea,均与产甲烷有关. 相似文献
197.
198.
不同相伴阴离子对镉污染红壤微生物区系及群落功能多样性的影响 总被引:8,自引:1,他引:8
通过外加醋酸镉和氯化镉的室内培养试验研究了不同相伴阴离子对镉污染红壤中微生物区系及群落功能多样性的影响 .结果表明 :在相同镉浓度下相伴OAc-对镉污染红壤的细菌、放线菌和真菌数量及微生物群落功能多样性的抑制作用大于相伴Cl-.统计分析显示 ,在供试红壤中OAc-与Cl-对其微生物区系及微生物群落代谢剖面 (AWCD值 )、Shannon指数的影响均达到显著差异 (P <0 0 5 ) ,且在红砂土上表现更为明显 .外加醋酸钾和氯化钾的培养试验结果表明 ,阳离子为钾时 ,相伴OAc-与Cl-对红壤微生物区系结构及群落功能多样性没有产生明显抑制作用 ,相伴OAc-甚至存在一定的刺激作用 .可见 ,相伴OAc-对镉污染红壤微生物的毒害作用大于相伴Cl-,其原因并非是阴离子本身的毒性效应 ,而镉的生物有效性变化可能是不同相伴阴离子镉盐导致毒性差异的原因之一 . 相似文献
199.
James R. Karr 《Environmental management》1987,11(2):249-256
Direct biological monitoring is essential for effective assessment efforts. Past approaches to biomonitoring are too simplistic (for example, toxicity testing, indicator species) or conceptually invalid (diversity indexes). Assessments that use ecological guilds use ecological principles in a more integrative fashion. The best long-term approach is development of suites of metrics, like those used in the index of biotic integrity (IBI), to reflect individual, population, community, and ecosystem attributes in an integrative framework. Efforts to use the conceptual content of IBI in a wider diversity of habitats should be encouraged and followed up with effective control actions. 相似文献
200.
Leonard F. DeBano Burchard H. Heede 《Journal of the American Water Resources Association》1987,23(3):463-470
ABSTRACT: Naturally occurring and man-made structures can be used for enhancing the development of riparian zones. Naturally occurring structures are cienagas, beaver dams, and log steps. Man-made structures include large and small channel structures and bank protection devices. All these structures affect streamflow hydraulics and sedimentation and can create a more favorable environment for riparian zone establishment. However, when they are used improperly, they can be destructive to existing riparian zones. Since stream processes are generally slow, long-time spans may pass before the effects of management action, good or bad, become visible. Also, the effects of large dam installations may appear a long distance downstream from the dam. Therefore, investigations must be of a wide scope. Interactions between riparian site, channel, and streamflow may be so complex that an interdisciplinary approach is required. 相似文献