环境荷尔蒙问题综观

由近来世界范围内的野生动物繁殖能力和人类精流质量等方面的异常问题开始,本文介绍了目前又一重大环境生态恶化因素－－环境荷尔蒙的种类、化学特性、来源、防治以及有关的发展动向。     

北京市郊铁路对乡村地区鸟类栖息地连通性的影响及优化

【目的】乡村地区是城市发展的依托基底和腹地空间,是国土生态安全的重要基础,探究线性工程项目对乡村地区生物栖息地的影响对中国生态文明建设具有重要意义。【方法】基于物种分布模型模拟北京乡村地区鸟类潜在适宜性生境,在分析栖息地连通性的基础上对市郊铁路的规划方案开展情景模拟并提出优化策略。【结果】1）北京乡村地区鸟类生境斑块主要分布在水体及附近,整体连通性水平较低且不均匀,南部鸟类迁徙路径受市郊铁路阻隔较严重,发生廊道断裂后栖息地连通性降低;2）依据模拟结果,提出分级保护生态廊道和激活生态源地生态效益,增加生态节点以提高生态网络连通性整体水平,优化生态断裂点并设缓冲区和回避距离的优化策略。【结论】北京市郊铁路降低了乡村地区鸟类栖息地连通性,由此提出综合性优化措施,以缓解相关负面生态效应,为生态文明建设和乡村振兴战略实施提供参考。     

人水和谐理念在水利工程设计中的实践

分析了苦溪河流域防洪整治及生态修复工程的基本情况和设计要求,论述了在壅水堰、护岸整治、沿河建筑物等工程的设计上如何保持和恢复生物多样性、维持生态系统稳定,并提出了相应的设计方案来实践人水和谐的设计理念.     

红曲黄酒酿造用曲及传统酿造过程中酵母菌的多样性研究

目的:探讨红曲黄酒酿造用曲中酵母菌多样性以及传统酿造过程中酵母菌菌群结构变化,为我国传统红曲黄酒中酵母菌资源的利用和对传统酿酒的有效控制及现代化酿酒新工艺的建立提供基础数据。方法:收集福建各地区的红曲黄酒酿造用曲20份,从中分离纯化出300株酵母菌,通过ITS1-5.8S-ITS2的PCR-RFLP指纹图谱对酵母菌进行分型,从各个分型类群中随机选取代表菌株,利用26S rDNA基因D1/D2区域序列分析进行分类鉴定;并采用PCR-RFLP快速分型鉴定技术分析红曲黄酒传统酿造过程中酵母菌菌群结构的变化。结果:从红曲黄酒酿造用酒曲中总共分离鉴定出12种类型酵母菌,其中扣囊复膜孢酵母(Saccharomycop-sis fibuligera)、酿酒酵母(Saccharomyces cerevisiae)和弗比恩毕赤酵母(Pichia fabianii)是酒曲中3种主要的酵母菌类型。红曲黄酒传统酿造过程酵母菌群的跟踪分析共鉴定出4种酵母菌,即酿酒酵母、扣囊复膜孢酵母、季也蒙毕赤酵母(Pichia guilliermondii)、粘性红圆酵母(Rhodotorula mucilaginosa)。在酿造前期扣囊复膜孢酵母是优势酵母菌,而在酿造的后期,酿酒酵母完全取代之成为优势菌。结论:红曲黄酒酿造用酒曲中的酵母菌具有丰富的生物多样性,红曲黄酒传统酿造过程酵母菌菌群结构处于动态变化,最终酿酒酵母成为酿造体系的优势酵母菌。     

小浪底水库下游浮游生物及细菌群落对水沙调控的响应规律

浮游动物、浮游植物和细菌群落广泛分布于河流生态系统,发挥着初级生产者、初级消费者和分解者的重要作用,对于环境条件的波动较为敏感。本文于2018—2019年黄河小浪底水库调水调沙前、中、后期对下游河流进行了调查采样,得出水环境因子、浮游生物与细菌群落的定量结果,以明确在不同调水调沙阶段下游河流水环境因子,浮游生物和细菌群落的演变规律及相互作用。通过结构方程模型(SEM)和基于距离的冗余分析(dbRDA)、分别明确了调水调沙影响下浮游生物以及细菌群落对水环境因子的响应规律。结果表明,调水调沙不同阶段下,浮游植物、浮游动物和细菌对于环境因子的响应方式具有较大的差异,溶解氧(在调水调沙前影响系数最大,为0.86)、温度(在调水调沙期间影响系数最大,为0.76),以及电导率(调水调沙后影响系数最大,为0.82)等环境因子对浮游生物的生物量影响最明显,而溶解氧(在调水调沙前)和叶绿素a(调水调沙期间至调水调沙后)对于细菌群落的影响最大。此外,调水调沙过程改变了浮游生物群落内部关系,削弱了浮游动物对浮游植物的捕食,同时也使得悬浮和沉积状态的细菌群落在样点之间的差异性增大。本研究明确了浮游生物及细菌群落在水沙调控不同阶段下对水环境因子的响应规律,对下游河流生态修复具有一定的理论意义。     

Identification of Priority Areas for the Conservation of Stream Fish Assemblages: Implications for River Management in France

Financial and human resources allocated to biodiversity conservation are often limited, making it impossible to protect all natural places, and priority areas for protection must be identified. In this study, we applied ecological niche models to predict fish assemblages in the stream network of France. Four non‐correlated conservation objectives were derived from these species assemblages: taxonomic diversity, functional diversity, natural heritage importance and socio‐economic value. We proposed a multi‐objective prioritization method based on the Pareto optimality principle to rank the planning units (i.e. 6097 subcatchments) according to their inherent trade‐offs between the four conservation objectives. Four types of hydrosystems of great conservation importance presenting specific fish assemblages were identified: (i) the most upstream areas of large catchments; (ii) the most downstream areas of large catchments; (iii) the small coastal catchments of the English Channel and the Atlantic Ocean; and (iv) the Mediterranean streams of medium altitude. The fish assemblages characterizing these hydrosystems were complementary and representative of the entire fish fauna of France. Most of these priority subcatchments were found to be practically suitable for the implementation of conservation actions, which is very promising for the protection of river biodiversity. Copyright © 2016 John Wiley & Sons, Ltd.     

我国水生植物多样性保护的研究与实践

20世纪90年代以来,随着国家、社会对水环境质量的日益关注,水生植物这一小众的生态类群在我国受到了越来越多的重视。从水生植物多样性编目、面临的危胁(湿地退化、水体富营养化、全球气候变暖、外来物种入侵)、相关的基础性研究(遗传多样性、土壤种子库、种子活力)和保护实践(自然保护区、种质资源库)等方面,对20世纪90年代以来的水生植物多样性研究工作进行梳理与展望,以期为后续更好的保护提供建议。     

基于GIS的四川植物物种丰富度与地形关系分析

利用四川省SRTM DEM和种子植物分布数据,在Arc GIS 10.1软件平台下运用其强大的多源数据处理和空间分析能力,定量分析该省植物物种丰富度和地形单元多样性,并在区域尺度上对两者之间的关系进行研究。结果表明:地形单元多样性指数介于0~0.86之间,指数较小的区域集中分布于成都平原、诺尔盖湿地和川西北高寒江源区等;指数较高的区域主要分布于四川盆地的盆周山区和川西的纵向岭谷区;全省种子植物物种多样性无论是在科、属、种阶元的丰富度,还是科、属的分化强度上,均表现出较为一致的空间分布格局和变化趋势,均呈现由盆地到盆周山区逐渐升高,再到高原(川西高原和攀西高原)又逐渐降低。总体上,种子植物物种丰富度随着地形单元多样性的增加而上升。研究结果初步揭示了区域尺度上植物物种多样性分布的地形背景,可为区域生态功能区划及流域生态保护与可持续发展提供科学的理论与数据支持。     

ECOLOGICAL FUNCTIONS OF FISH BYPASS CHANNELS IN STREAMS: MIGRATION CORRIDOR AND HABITAT FOR RHEOPHILIC SPECIES

The introduction of weirs into stream ecosystems resulted in modifications of serial continuity and in the decline of riverine fish species. Successful river restoration requires information on the ecological functionality of fish bypass channels that are considered an ecological improvement according to the European Water Framework Directive. In this study, we compared the functionality of three nature‐oriented fish passes as compensatory habitats and migration corridors for fishes. Fish passes differed significantly from upstream and downstream reaches of the weirs, revealing higher current speed, lower water depth, smaller channel width and greater habitat variability. Following these structural differences, they provided key habitats for juvenile, small and rheophilic fishes that are typically underrepresented in highly modified water bodies. All fish passes were used as migration corridors, with increased fish movements during high discharge and at spawning periods. Because river stretches with high variability of current speed and water depth are scarce in highly modified water bodies, fish passes can play an important role as compensatory habitats and should thus be considered more intensively in habitat assessments and river restoration. Ideally, fish bypasses should mirror the natural discharge dynamics and consider all occurring fish species and sizes. Copyright © 2011 John Wiley & Sons, Ltd.