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991.
通过对萍水河监测断面水质监测数据的分析,利用内梅罗污染指数法及秩相关系数法进行水质评价,分析了"十二五"期间萍水河水质情况及其变化趋势,阐述了萍水河的水质空间分布规律。结果表明:萍水河断面水质以Ⅱ类、Ⅲ类为主,水质总体较好,但呈下降趋势;其上游水质较好,中游较差,下游略有好转,麻山河等萍水河支流水质较好。 相似文献
992.
依托于地理信息系统空间数据管理和空间信息分析的功能,利用高分辨率遥感影像研究隔离方案划定的技术流程。该技术流程主要包括收集水源地基础资料、解译高分辨率遥感影像、提取土地覆盖分类信息、建立空间数据库、划定物理隔离和生物隔离的区段。该种技术流程也适用于地形复杂、一级保护区面积较大的地下型水源地。 相似文献
993.
994.
Occurrence, compositional patterns, and possible sources of polybrominated diphenyl ethers in agricultural soil of Shanghai, China 总被引:3,自引:0,他引:3
The present study analyzed surface soil collected from agricultural region of Shanghai to determine the occurrence, compositional patterns and possible sources of polybrominated diphenyl ethers (PBDEs). The results showed that 32 PBDEs were detected among 44 target PBDEs. Total PBDE concentrations ranged from 129 to 1245 ng kg−1 with a mean of 429 ng kg−1. BDE209 was the predominant congener in a range of 33.2-796 ng kg−1 with a mean of 254 ng kg−1. Meanwhile, BDE47, BDE49, BDE153, BDE190, and BDE99 have the most abundant with high concentrations and detectable frequencies. PBDE congeners and homologues analysis and principal component analysis (PCA) also revealed that the major source of PBDE in the soil samples was associated with the prevalent use of technical decabromodiphenyl ether (Deca-BDE) and pentabromodiphenyl ether (Penta-BDE). The correlation analysis proved that there was a significant correlation between total organic carbon (TOC) and lower brominated PBDEs, indicating the significant diffuse nature of the sources of these congeners. 相似文献
995.
996.
Effects of alfalfa and organic fertilizer on benzo[a]pyrene dissipation in an aged contaminated soil
Fu D Teng Y Luo Y Tu C Li S Li Z Christie P 《Environmental science and pollution research international》2012,19(5):1605-1611
BACKGROUND: A climate-controlled pot experiment was conducted to investigate the effects of planting alfalfa and applying organic fertilizer on the dissipation of benzo[a]pyrene from an aged contaminated agricultural soil. RESULTS: Short-term planting of alfalfa inhibited the dissipation of benzo[a]pyrene from the soil by 8.9%, and organic fertilizer enhanced benzo[a]pyrene removal from the soil by 11.6% compared with the unplanted and unfertilized treatments, respectively. No significant interaction was observed between alfalfa and organic fertilizer on benzo[a]pyrene dissipation. Sterilization completely inhibited the removal of benzo[a]pyrene from the soil indicating that its degradation by indigenous microorganisms may have been the main mechanism of dissipation. Furthermore, significant positive relationships were observed between benzo[a]pyrene removal and the contents of soil ammonium nitrogen, nitrate nitrogen, and total mineral nitrogen at the end of the experiment, suggesting that competition between plants and microorganisms for nitrogen may have inhibited benzo[a]pyrene dissipation in the rhizosphere of alfalfa and the addition of organic fertilizer may facilitate microbial degradation of benzo[a]pyrene in the soil. 相似文献
997.
Feasibility study on cross-linked biopolymeric concrete encapsulating selenium glass wastes 总被引:3,自引:0,他引:3
Feasibility study was conducted to encapsulate the selenium (Se) contained in glass waste, using the biopolymer-modified concrete. Biopolymer has unique characteristics to provide the chemical sites to metals or toxic compounds through the three-dimensional cross-linked structure. Very minute amount of biopolymer enhanced the characteristics of cementitious material. The resulting biopolymeric composite with selenium glass waste showed 20% higher compressive strength than ordinary concrete and the lower leaching concentration than the equipment detection limit. For a qualitative measurement, X-ray diffraction (XRD; X-ray powder diffractogram) was used to characterize the biopolymeric concrete. The optimum waste content percentage with appropriate biopolymer concrete mixture ratio was identified for its possible commercial use. 相似文献
998.
常规组合工艺-稳定塘-湿地系统处理印染废水 总被引:1,自引:1,他引:0
针对工业园区印染企业产生的印染废水和生活污水,采用独特的"常规组合工艺与‘植物稳定塘-人工湿地系统’联合工艺"对其进行集中统一处理,并考察了运行效果。数据结果表明,系统出水COD、BOD5、SS、色度、NH3-N和TP平均分别为63.2 mg/L、13.8 mg/L、5.0 mg/L、49倍、0.2 mg/L和0.4 mg/L,出水水质达到国家污水综合排放一级标准(GB8978-1996)。该工艺运行稳定,可有效去除废水中的COD、SS和色度,去除率均在90%以上。按日均处理量4×104m3计算,此工艺每年将削减COD排放近30万t。 相似文献
999.
JZ9-3油田含聚采油污水粘度高、稳定性强,严重影响到现场污水处理流程和设备的运行。为解决这一问题,通过对JZ9-3油田污水处理流程和单元设备的模拟,进行了现场3种净水剂和不同含聚量的含油污水对斜管除油器、气浮选器和过滤器的影响研究。阳离子型净水剂BHQ-203和ICA的除油效果较阴离子型净水剂BHQ-08的除油效果好,能起吸附电中和及架桥作用,斜管除油器处理不同含聚含油污水后其含油量由263.2 mg/L下降到20.73 mg/L,气浮选器的除油率9%~34%,过滤器在进水含油较低(<50 mg/L)的情况下,起到强化除油的作用;含聚量增加,过滤后悬浮物量呈下降趋势,过滤困难,含聚量达到一定值(>600 mg/L)后无法分析悬浮物量;斜管除油器、气浮选器和过滤器出口水样的ζ电位值在-22.5~-42 mV,随含聚量的增加而变小,污水稳定性增加。研究结果用以指导现场工艺设备的改造。 相似文献
1000.
Climate Change Adaptation Among Tibetan Pastoralists: Challenges in Enhancing Local Adaptation Through Policy Support 总被引:2,自引:0,他引:2
While researchers are aware that a mix of Local Ecological Knowledge (LEK), community-based resource management institutions, and higher-level institutions and policies can facilitate pastoralists' adaptation to climate change, policy makers have been slow to understand these linkages. Two critical issues are to what extent these factors play a role, and how to enhance local adaptation through government support. We investigated these issues through a case study of two pastoral communities on the Tibetan Plateau in China employing an analytical framework to understand local climate adaptation processes. We concluded that LEK and community-based institutions improve adaptation outcomes for Tibetan pastoralists through shaping and mobilizing resource availability to reduce risks. Higher-level institutions and policies contribute by providing resources from outside communities. There are dynamic interrelationships among these factors that can lead to support, conflict, and fragmentation. Government policy could enhance local adaptation through improvement of supportive relationships among these factors. While central government policies allow only limited room for overt integration of local knowledge/institutions, local governments often have some flexibility to buffer conflicts. In addition, government policies to support market-based economic development have greatly benefited adaptation outcomes for pastoralists. Overall, in China, there are still questions over how to create innovative institutions that blend LEK and community-based institutions with government policy making. 相似文献