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1.
Environmental conditions in cooling ponds of thermal power plants are favorable for marsh frogs. Their populations inhabiting Verkhne-Tagil and Reftinskoe reservoirs differ in some traits, such as size and age composition, growth rate after metamorphosis, spawning type, fecundity, and characteristics of larval development. Differentiation in body size manifests itself at the early stages of terrestrial life and progresses at later stages. As a consequence, larger individuals may reach maturity and participate in reproduction at an earlier age.  相似文献   
2.
以闽江河口塔礁洲感潮淡水野慈姑(Sagittaria trifolia Linn.)湿地为研究对象,于2016年2、4、7和9月每月均在连续2个小潮日内向研究样地施加人造海水和Fe(OH)_3溶液,研究短期的盐水入侵及Fe(III)浓度增强对河口感潮淡水湿地土壤反硝化速率及理化特征的影响.结果表明,短期的盐水入侵、Fe(III)浓度增强对河口感潮淡水沼泽湿地土壤反硝化速率的影响不显著,然而,盐水和Fe(III)共同施加会显著提高湿地土壤反硝化速率,与对照(CK)相比,盐水和Fe(III)共同施加可使土壤反硝化速率提高270.9%.盐水入侵、盐水和Fe(III)共同施加均可显著提高湿地土壤、间隙水的电导率及Cl~-、SO_4~(2-)的含量;Fe(III)浓度增强可显著降低土壤和间隙水pH值,同时显著提高土壤三价铁含量.  相似文献   
3.
滨州沿海湿地生物多样性保护探讨   总被引:1,自引:0,他引:1  
王真 《干旱环境监测》2006,20(4):215-218
重点研究了该区域海洋生物多样性、淡水生物多样性、陆生和海岛等高等植物多样性、陆栖动物多样性与特点。分析了其破坏现状及原因,提出了生物多样性保护对策和可持续利用途径。  相似文献   
4.
人工湿地植物在污水处理系统中的作用探讨   总被引:8,自引:0,他引:8  
人工湿地污水系统由于具有独特的净化机理和功能而越来越多地被用于处理生活污水和工业废水.湿地植物在人工湿地中起着非常重要的作用,不但可以直接摄取和利用污水中的营养物质、吸收富集污水中的重金属等有毒有害物质;而且还能输送氧气到根区,提供根区微生物生长、繁殖和降解过程中对氧的需求.文章通过详细阐述植物对水中营养元素的吸收作用,说明了植物在人工湿地处理污水中的重要性.  相似文献   
5.
Subsidence is a primary factor governing marsh deterioration in Mississippi River deltaic plain coastal marshes. Marsh surface-water level relationships are maintained primarily through soil organic matter accumulation and inorganic sediment input. In this study we examined the role of soil organic matter accumulation in maintaining marsh elevation in a brackish Spartina patens marsh. Measured rates of soil organic accumulation were compared to plant biomass production and soil respiration (carbon dioxide and methane emission) at the study sites. The study demonstrated the importance of plant biomass production to soil organic carbon accumulation in maintaining viable Spartina patens marshes in sediment-deficient coastal environments. The role of Mississippi River freshwater reintroduction in maintaining conditions for organic accretion is discussed.  相似文献   
6.
Environmental heterogeneity is increasingly being used to select conservation areas that will provide for future biodiversity under a variety of climate scenarios. This approach, termed conserving nature's stage (CNS), assumes environmental features respond to climate change more slowly than biological communities, but will CNS be effective if the stage were to change as rapidly as the climate? We tested the effectiveness of using CNS to select sites in salt marshes for conservation in coastal Georgia (U.S.A.), where environmental features will change rapidly as sea level rises. We calculated species diversity based on distributions of 7 bird species with a variety of niches in Georgia salt marshes. Environmental heterogeneity was assessed across six landscape gradients (e.g., elevation, salinity, and patch area). We used 2 approaches to select sites with high environmental heterogeneity: site complementarity (environmental diversity [ED]) and local environmental heterogeneity (environmental richness [ER]). Sites selected based on ER predicted present‐day species diversity better than randomly selected sites (up to an 8.1% improvement), were resilient to areal loss from SLR (1.0% average areal loss by 2050 compared with 0.9% loss of randomly selected sites), and provided habitat to a threatened species (0.63 average occupancy compared with 0.6 average occupancy of randomly selected sites). Sites selected based on ED predicted species diversity no better or worse than random and were not resilient to SLR (2.9% average areal loss by 2050). Despite the discrepancy between the 2 approaches, CNS is a viable strategy for conservation site selection in salt marshes because the ER approach was successful. It has potential for application in other coastal areas where SLR will affect environmental features, but its performance may depend on the magnitude of geological changes caused by SLR. Our results indicate that conservation planners that had heretofore excluded low‐lying coasts from CNS planning could include coastal ecosystems in regional conservation strategies.  相似文献   
7.
苦咸水淡化处理方法探讨   总被引:12,自引:0,他引:12  
针对苦成水的淡化水处理方法,分别介绍了不同方法的原理、试用性和优缺点。通过对各种方法的对比,采用反渗透膜法对不同古盐量的苦成水进行脱盐淡化处理,具有较强的适应性。膜分离技术中的反渗透法是较其他方法更为合理、有效的苦咸水淡化技术。  相似文献   
8.
This work evaluates the role of a plant community in mercury (Hg) stabilization and mobility in a contaminated Portuguese salt marsh. With this aim, the distribution of Hg in below and aboveground tissues, as well as the metal partitioning between cellular fractions (soluble and insoluble) in four different species (Triglochin maritima L., Juncus maritimus Lam, Sarcocornia perennis (Miller) A.J. Scott, and Halimione portulacoides (L.) Aellen) was assessed. Mercury accumulation, translocation and compartmentation between organs and cellular fractions were related to the plant species.Results showed that the degree of Hg absorption and retention was influenced both by environmental parameters and metal translocation/partitioning strategies. Different plant species presented different allocation patterns, with marked differences between monocots (T. maritima and J. maritimus) and dicots (S. perennis, H. portulacoides). Overall, the two monocots, in particular T. maritima showed higher Hg retention in the belowground organs whereas the dicots, particularly S. perennis presented a more pronounced translocation to the aboveground tissues. Considering cellular Hg partitioning, all species showed a higher Hg binding to cell walls and membranes rather than in the soluble fractions. This strategy can be related to the high degree of tolerance observed in the studied species. These results indicate that the composition of salt marsh plant communities can be very important in dictating the Hg mobility within the marsh ecosystem and in the rest of the aquatic system as well as providing important insights to future phytoremediation approaches in Hg contaminated salt marshes.  相似文献   
9.
厌氧发酵沼气工程的工艺及存在的问题   总被引:2,自引:0,他引:2  
利用厌氧消化技术处理畜禽养殖废水,制取清洁能源——沼气,在治理污染的同时变废为宝,减少温室气体的排放,从而实现国民经济的可持续性发展。本文概述了集约化畜禽养殖场废污水处理中采用的厌氧发酵工艺,以及厌氧发酵沼气工程中存在的问题。  相似文献   
10.
近20余a来,互花米草在我国沿海及河口滩涂快速扩散,已成为我国海岸盐沼中最重要的入侵植物。上海崇明东滩是我国长江口的国际重要湿地,目前受到了互花米草入侵的严重威胁。自1995年在崇明东滩首次发现互花米草以来,互花米草的分布面积已超过1 600 hm2。总结了近几年在崇明东滩进行的互花米草相关研究,旨在对互花米草的控制与管理提供科学依据。目前互花米草主要分布在崇明东滩的东部及北部,决定其入侵动态与分布的主要因素在于:(1)互花米草对沿海滩涂环境具有良好适应与耐受能力;(2)人为引种大大加快了互花米草的扩张速度;(3)崇明东滩湿地的水分盐度条件特征导致互花米草主要分布在崇明东滩的东部与北部。根据互花米草的生理学特征和长江口地区的水文特点可以推断:互花米草在东滩东部和北部将继续扩张,但目前尚难入侵东滩南部区域,而人类活动可能加剧互花米草入侵。根据互花米草的入侵现状和趋势,必须尽快采取多种途径对互花米草进行控制和管理  相似文献   
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