适宜植物遴选是干热河谷库区消落带修复的关键.为筛选干热河谷库区消落带修复适宜耐淹抗旱植物,检验消落带修复有效性,本文以乌东德水电站库区己衣镇新民村消落带修复区为研究对象,结合定量与定性分析方法,观察并分析了不同物种、大小规格、种植海拔的植物在长期水淹后的生长和恢复情况.结果表明:(1)少量乡土植物可在消落带上段生长存活,乡土植物桑树、狗牙根、苍耳、苘麻可在整个消落带区域生长;(2)引进植物池杉、中山杉、乌桕、枫杨、小梾木、秋华柳可在干热河谷库区消落带区域生长;(3)大规格苗木在消落带生长更好,种子播种修复效果不佳;(4)修复区植物生长受干热气候、病虫害和种间竞争等因素影响.研究结果可为后续干热河谷库区消落带修复研究积累基础数据与实践经验.

梯级电站的开发对洄游鱼类天然生境造成了严重破坏且阻断了其洄游路径.以金沙江下游某典型高坝工程为例,选取圆口铜鱼为保护对象,对过鱼季节典型工况尾水下游河道进行了三维紊流数值模拟,分析了河道中流速、水深的分布情况,采用栖息地综合适宜度评价方法在研究区域内以流速、水深为评价因子对圆口铜鱼进行了洄游期水力生境适宜度评价,计算了不同工况下权值适宜面积占比.结果 表明,各工况下主流流速较大,圆口铜鱼无法克服主流完成上溯;在主流靠近左右岸两侧存在水力生境适宜区间,权值适宜面积随着下泄流量增大而减小;在左岸x=-850、-1450 m和右岸x=-1300 m、-1600 m四处存在可能的集群区域,可为过鱼设施建设提供参考.

干热河谷库区消落带生态修复关键技术难点在于当消落带植被受到长时间淹水与干旱交替双重胁迫时,如何遴选生态修复两栖植物.通过对乌东德库区消落带生态修复试验段淹没前植被调查、溪洛渡库区和三峡库区典型库岸消落带现存植物种群调查以及查阅三峡库区消落带植被自然演替和植被修复相关文献,结合乌东德水电站水位调度节律和库区干热河谷气候条件,对乌东德库区消落带植被自然演替趋势进行了分析.按照自然修复与人工修复相结合、乡土植物与外来植物相结合的消落带生态修复理念,遴选出乌东德库区消落带生态修复试验植物,提出了在试验段沿海拔高程的植物梯度配置模式:消落带中下部配置以狗牙根、香附子、扁穗牛鞭草等为主的多年生草本植物和以苘麻、狗尾草、马唐等为主的一年生草本植物;消落带上部配置以中山杉、水桦、桑树、秋华柳、银合欢等为主的乔、灌木以及草本植物.

消落带土壤水分是制约植物生长发育的关键因素,对库区消落带生态修复意义重大.本文系统分析了乌东德库区消落带修复试验区土壤含水量分布,探索了土壤水分空间变化和影响因素.结果表明:研究区5月水分含量低于5％,不同试验分区和高程区域土壤水分分布受到微地形、土壤特征、植被类型和植被覆盖度等影响.土壤水分随深度变化的主控因素包括地表蒸发和植物吸水,剖面深度大于50 cm的土壤水分是消落带植物潜在利用水源之一.本研究为干热河谷库区消落带土壤水分研究积累了基础资料,为消落带生态修复提供理论参考.

金沙江是长江上游的重要组成部分,河床陡峻,流水侵蚀力强,是长江干流泥沙的主要来源之一.实验研究了金沙江攀枝花段沉积物中六种典型重金属的时空分布特征,分析了金沙江流域沉积物对镉(Cd)的吸附/解吸能力和环境因素产生的影响,并与长江干流武汉段沉积物进行对比.实验结果表明沉积物中六种典型重金属平均浓度V>Zn>Cu>Pb>As>Cd.除少部分断面外,沉积物中重金属浓度在丰水期最高.干流沉积物中重金属平均浓度高于支流,Zn、V、Cd和Pb的浓度自上游至下游逐渐降低.金沙江攀枝花段沉积物和长江干流武汉段沉积物对Cd吸附/解吸规律基本一致,两种沉积物对Cd的吸附均大于解吸.与长江沉积物相比,金沙江沉积物吸附速率更快,但两者平衡吸附量相近,均在135 mg/kg左右.水体扰动对两种沉积物的吸附/解吸过程影响较大,随水体扰动程度增加,沉积物和溶液中Cd接触面增大,导致Cd在沉积物上吸附量变大.温度变化则只影响吸附/解吸速度但不影响两种沉积物的平衡吸附量.

金沙江干热河谷是我国重要的水利水电开发区.该区域水电站水库建成运行后将产生大面积库区消落带,严重威胁当地生态环境.本文从金沙江干热河谷水电站库区消落带植被现状、物种筛选、植物生理生态响应、植被恢复模式与技术、恢复生态效益评价等方面概括总结了该区域植被恢复研究进展与现状.针对金沙江干热河谷水电站库区消落带现有植被恢复研究实践不足的现状,提出该区域植被恢复宜根据地形地貌,结合生物技术和工程技术,综合利用多种生活型植物的植被恢复思路,指出金沙江干热河谷水电站库区消落带植被恢复未来研究重点,包括实践与示范、生态系统长期动态监测和管理政策研究等方向.

悬移质泥沙是水环境的重要参数之一,其含量的变化对流域生态环境有着多方面的影响.传统研究方法能够实现悬移质泥含量的精确分析,但存在布点有限、时效不足等问题,而遥感技术可弥补传统研究方法的不足,实现大面积水域的同步观测.基于悬移质泥沙含量遥感反演的4类模型:物理模型、半分析模型、经验模型、人工智能算法模型,总结了Ⅱ类水体悬移质泥沙含量遥感反演的研究进展,探讨了反演研究中存在的离水辐亮度提取难度大、混合像元不易分解等问题,并针对我国内陆山区河流,提出山区Ⅱ类水体悬移质泥沙含量遥感反演发展面临的关键问题.

This study investigated the genetic diversity and population demographic history of Hemiculterella sauvagei based on the sequence analysis of mtDNA (Cyt b) of 168 individuals from five geographical populations including Shuiliao, Maotai, Erhe, Taiping and Chishui. After alignment, 1137 bp sequence including 42 variable sites, 13 singleton sites, 29 parsimony informative sites and 38 haplotypes were acquired and revealed, among which Hap1, Hap2 and Hap6 were shared by all populations. The haplotype diversity (Hd) and nucleotide diversity (Pi) were 0.895±0.012 and 0.00487±0.00695, respectively. Analysis of molecular variance (AMOVA) indicated that genetic varia-tions between different geographical populations in the Chishui River were mainly within group. Genetic differentia-tion index (Fst) indicated high genetic differentiation between Chishui and Maotai, Erhe and Shuiliao population as well as medium genetic differentiation between Chishui and Taiping population. The overall mean genetic distances among five populations were between 0.004—0.006. Tajima's D and Fu's Fs neutral tests showed that historical population ex-pansion observed in Taiping, Shuiliao and Chishui population but not in Maotai and Erhe. The population expansion of Shuiliao, Taiping and Chishui appeared in 0.43 Mya, 0.40 Mya and 0.37 Mya, respectively.

相对于大型水电站,小水电站耗资少,环境破坏也较小,且对西南偏远地区和少数民族地区的用电、江河治理、发展地方社会经济等方面具有重要作用.但是,过快、过度、无序的小水电开发也对河流生态系统造成了一定的影响.目前,大量处在运行期的小水电正在接受国家绿色可持续化发展要求的检验.为此,我国首次提出了《绿色小水电评价标准(征求意见稿)》(以下简称《标准》),作为绿色小水电评价与认证的参考依据.通过对《标准》进行剖析,结合国外具有代表性的绿色水电标准的有利经验,设想了以"绿色可持续化"为核心,从评价内容、指标体系和评价周期等方面对绿色小水电评价标准进行完善.针对我国仍缺乏严格的认证机构和有力的监管手段的问题,从政策推动、激励机制、约束和惩罚措施等方面探讨了奖惩制度的建立,可进一步完善绿色小水电评价标准.

[Objective] The spatial and temporal distribution of rainfall erosion in the Jinsha river basin from 1998 to 2015 were analyzed,to provide references for optimizing the quantitative prediction of soil loss in watershed and the planning of soil and water conservation.[Methods] The rainfall data of the meteorological stations were used to verify the applicability of TRMM precipitation data.Upon which,the rainfall erosion force in Jinsha river basin was estimated using daily precipitation model.The estimation was conducted by combining with weather stations data,TRMM and DEM data,and in the support of Arc/Info software's map algebra operation function.[Results] The TRMM 3B42 rainfall data and weather station precipitation data were used to estimate the rainfall erosion force in Jinsha river basin for many years,and the average overall accuracy reached 82％,illustrating that the estimation of rainfall erosion by the two sourced data was within the reasonable range of error.The estimated rainfall erosion force had regional difference and elevation difference,from the southeast to the northwest,it had a general diminishing trend;the smaller the elevation was,the greater the rainfall erosion.The inter annual change in the basin also had spatial differentiation,and the overall temporal trend was decreasing.[Conclusion] It is feasible to apply TRMM 3B42 precipitation data to the annual mean rainfall erosion force estimation in the Jinsha River basin.However,the consistency of each site's estimation results was different,and the applicability of certain years was influenced by extreme weather.