三峡库区澎溪河消落带生态系统修复实践探索

三峡水库蓄水后水位季节性波动给消落带带来了极大的环境胁迫。如何进行消落带生态系统修复,优化其生态系统服务功能,基于自然的解决方案是解决消落带复杂环境问题的重要途径。以位于三峡库区的澎溪河流域消落带为例,在阐述消落带生态系统修复设计策略和技术框架的基础上,结合持续10余年的消落带生态系统修复实践,分析了植物物种筛选及种源库建立、近自然植物群落构建、多功能基塘修复、复合林泽修复、多维湿地修复、地形-底质-植物-动物协同修复等技术的综合应用及其成效。结果表明,所筛选的植物耐淹性能及存活状况良好,修复后的消落带植物群落结构稳定,生物多样性提升、面源污染削减效果明显。澎溪河流域消落带生态系统修复实践解决了大幅度水位变化和冬季深水淹没的三峡水库消落带生态修复难题,创新性地构建了水库消落带生态系统修复技术体系,为大型湖库消落带生态修复提供了可推广、可复制的技术方法及实践模式。     

水库消落区湿地化改造技术及植被改善效应

受水位波动的影响，水库消落区普遍存在植被退化问题，这一问题在北方水库尤为突出。消落 区湿地化改造是针对消落区的植被退化问题通过持续的水分补给构建稳定的湿地生态系统，实现对落 干消落区植被覆盖度和生物量的提高。以碧流河水库蛤蜊河入库口旁侧消落区为研究对象，开展消落 区湿地化改造的实例研究，通过对比工程前后植物物种和 ＮＤＶＩ变化，分析其对区域植被的影响。研究 结果表明:湿地化改造提高了区域植物物种多样性；充分的水分补给使得植物物种由喜旱植物为主向喜 湿植物为主转变；2019年区域 ＮＤＶＩ平均值相比于 2015年增长 14．59％，方差降低 46．8％，工程实施后 消落区植被的覆盖度和均匀度得到提高。消落区湿地化改造能够有效改善消落区在落干时期植被条 件，是改善消落区生态环境的有效途径。     

三峡库区消落带的生态环境问题及其调控

长江三峡水库蓄水运行后将出现一个落差达30m的消落带,探讨了水库运行过程中消落带可能产生的一系列严峻的生态与环境问题,如:岸边污染带的形成、可能诱发流行性病情和疫情的发生、消落带的环境地质灾害加剧、消落带植物多样性受损、生态系统更为脆弱等,并针对这些问题的产生原因、时空分布特征及趋势,提出了有针对性的防治措施。     

水库消落带蓉草单混种植对水位变化适应性的模拟研究

通过野外模拟周调节水库消落带水位变化研究,表明单种蓉草前期及冬季生长和繁殖受抑制影响明显,呈现下降—逐渐稳定—趋于回升的趋势;与香根草混植的蓉草的叶长、叶宽、成活率及覆盖率等均优于单种的蓉草,可推荐作为周调节水库消落带植被恢复的植物组合。     

江西省大中型水库消落带问题分析与思考

采用典型点实地调研与问卷调查相结合的方式,对江西省大中型水库消落带的当前情况进行普查,初步了解江西省大中型水库消落带的面积和目前利用、治理模式,分析水库消落带存在的问题,提出水库消落带的开发利用与生态修复的可行性建议.     

大宁调蓄水库消落带生态修复水生植物配置方法研究

近年来,水库消落带生态风险和水环境问题,逐渐被重视.用生态办法解决生态问题,是增加水库消落带生态韧性和调控生态演变趋势的重要手段.通过对大宁调蓄水库消落带生态修复水生植物配置方法研究,筛选出适宜的水生植物,可用于优化同类或类似水库消落带植被配置,具有一定的实际指导作用.     

浙江省青山水库消落带湿地植物根际土壤真菌群落结构

为了研究水库消落带湿地中的植物及其根际土壤微生物对水库生态系统稳定性的维持和水库水质的改善具有重要作用,通过采用高通量测序方法,测定了位于浙江省杭州市临安区的青山水库消落带湿地植物根际土壤真菌群落结构以及多样性.结果表明,浙江省青山水库消落带湿地各建群种植物间其根际土壤真菌丰富度指数(ChaoI指数)和多样性指数(Shannon指数)存在明显的差别.Shannon和ChaoI都以旱茅的根际土壤样品为最高,其次是狗牙根根际土壤样品,而以荻根际土壤真菌Shannon和ChaoI的指数值最低.在门水平上,相对丰度最高的菌群为子囊菌门;在纲水平上,相对丰度最高的菌群为粪壳菌纲.在目水平上,相对丰度最高的为Ascomycota_unclassified.在科水平上,相对丰度较高的有Ascomycota_unclassified、口蘑科Tricholomat-aceae.在属水平上,相对丰度较高的有Ascomycota_unclassified、unidentified、杯伞属.     

青狮潭罐区续建配套节水改造成效显著

青狮潭水库位于广西壮族自治区桂林市灵川县青狮潭乡,是一座以城乡供水、农业灌溉、防洪、漓江旅游补水和发电等功能综合利用的大型水库,总库容6亿m~3,水库流域集雨面积474km~2。青狮潭水库灌区于1960年7月建成投入运行,灌区设计灌溉面积2.79km~2,总土地面积984km~2。青狮潭     

八家河入库消落带植物分布调查与分析

文中采用多光谱无人机及实地考察,对大连市碧流河水库的八家河入库段消落区展开了植物群落结构及样方生物量的空间分布特征调查与分析,并从生境角度出发,描述植物在不同生境条件下的生物量分布特点,分析生境指标对植物生长状况的影响,并推求研究区域内的植物、生物总量,为后来改造入库生境、提高消落带植物的污染防控能力打下基础.     

库滨消落带污染调查及治理对策

库滨消落带具有明显的生态脆弱性、易污染性和易破坏性,是威胁水库水质安全的主要因素之一。文中通过对碧流河水库库滨消落带进行实地调研,将库滨消落带依地势进行分类,分析并总结了库滨消落带的污染类型,并提出相应的治理对策,为库滨消落带污染治理提供参考。     

广东省水库消落带几种植物对淹水环境适应性的模拟研究

模拟了周调节水库的消落情况,对几种植物的水淹环境适应性进行评价和筛选。结果表明:周调节水库消落带上单种的香根草、狗牙根、蓉草的各项形态指标均比岸坡未受淹的植株低20%~50%,香根草、狗牙根、蓉草的生长和繁殖受到水淹环境的抑制;百喜草的各项形态指标则与岸坡上的无显著差异,说明百喜草能较好地适应短时间的水淹环境;香根草和百喜草在整个试验期内都保持较高的成活率;经过一段适应期后,香根草和百喜草生长稳定,而随着冬季的到来,香根草和百喜草的生长速度变缓,覆盖率逐渐降低,保持在30%~40%左右,且在春季发芽恢复生长;蓉草和狗牙根在冬季成活率较低,且明显低于岸坡未受淹的蓉草和狗牙根;春季狗牙根能够重新发芽生长,但蓉草复绿较少。总体来看,香根草、百喜草、狗牙根可作为水淹时长较短的消落带的植被恢复备选植物。     

Secondary seed dispersal in hydro‐fluctuation belts and its influence on the soil seed bank

The completion of the Three Gorges project altered the water level fluctuations from “summer submersion and winter exposure” to “summer exposure and winter submersion.” The reverse seasonal flooding has dramatically changed both the time and duration of exposure and submergence of reservoir banks. Secondary seed dispersal by water is the primary method of dispersal in hydro‐fluctuation belts. This study conducted field sampling and germination experiments to evaluate the effects of reverse seasonal flooding on species composition, diversity, and density of the secondary seed dispersal system and the soil seed bank, and their changes with elevation, in the Xiangzi River. The results indicate that that the secondary seed dispersal system and soil seed bank were associated with 42 and 50 plant species, respectively, and their average seed densities were 1,876.27 and 7,322.18 seeds/m², respectively. The quantity of seeds from secondary seed dispersal accounted for 20.40% of the soil seed bank. The species life‐form composition of both consisted mainly of annual and perennial grasses. Among these grasses, the dominant species in the secondary seed dispersal system were Cynodon dactylon and Paspalum distichum, whereas the dominant species in the soil seed bank were Solanum nigrum and Rumex dentatus. Due to the effects of reverse seasonal water level fluctuations, the species composition and quantity of the soil seed bank and secondary seed dispersal system largely exhibited similar spatial distribution characteristics, but some differences were observed. The species quantity, species diversity index, and seed density in the soil seed bank were the highest in the middle section of the hydro‐fluctuation belt, followed by the top section and then the bottom section. Conversely, the species quantity, species diversity index, and seed density in the secondary seed dispersal system were highest at the top section, followed by the middle section and then the bottom section.     

Nutrients and water level fluctuations: A study of three aquatic plants

Water holes characteristic of the middle sections of fragmented, lowland, semi‐arid rivers act as refuge areas for biota during low flow and drought. However, river regulation and catchment development has altered the hydrological and nutrient status of these refuges. A series of artificial ponds were used to imitate these habitats and experiments were designed to determine whether stochastically fluctuating water levels with maximum amplitude of 65 cm would counteract the influence of nutrient enrichment on the growth of three key aquatic plant species. The species (Cyperus gymnocaulos, Triglochin procerum and Typha domingensis) represented different functional groups that inhabit contrasting zones across the elevation gradient. Each species was grown at a different elevation within the experiment reflecting each species' elevation preference and supplied with the equivalent to 0, 10 or 30 g N m^?2 year^?1. Under a static water regime nutrient enrichment doubled the total biomass of all three species. In contrast under a fluctuating water regime, nutrient addition did not influence total biomass of either T. domingensis or T. procerum and the performance of C. gymnocaulos was reduced by ca. 30%. These data suggest that if environmental flows were managed to provide a natural stochastically fluctuating water regime, this would nullify the influence of nutrient enrichment and limit the distribution and spread of invasive species such as Typha, that exists under the current altered conditions. Copyright © 2010 John Wiley & Sons, Ltd.     

假俭草生态学特性及在水利工程中的应用研究

在收集不同地区野生假俭草的基础上,进行田间种植试验并对其生物学特性和生态学特性进行综合评价。试验表明,假俭草“涵宇一号”具有绿期长、成坪速度快、抗逆性强,根系发达、维护简便等优点。该品种利用根茎繁殖、植生带、液压喷播等技术在水库、堤防等水利工程中得到了广泛的应用,是防治水土流失和改善环境的理想植物材料。     

天津滨海新区湿地植物群落特征及植被演替过程

为了研究滨海新区湿地植物的特征和生态效益,更好的了解湿地植物群落的价值,研究了湿地植物的种类及区系组成、植物多样性及其分布、湿地植被的演替规律,研究得出本区湿地植物种类较多,共232种,科属种分布广泛,植物丰富度较高,均匀度一般,湿地植物受水盐程度影响较大,演替过程主要由水盐程度主导;水分多时向湿生水生植物演替如碱菀、芦苇等,水分少盐度高时多发生向中生盐生植物的演替如獐毛等。     

Hydrology influences generalist–specialist bird-based indices of biotic integrity in Great Lakes coastal wetlands

Marsh bird habitats are influenced by water levels which may pose challenges for interpreting bird-based indices of wetland health. We determined how much fluctuating water levels and associated changes in emergent vegetation influence the Index of Marsh Bird Community Integrity (IMBCI) using data collected in Great Lakes coastal wetlands by participants in Bird Studies Canada's Great Lakes Marsh Monitoring Program. IMBCI scores for 90 wetlands in Lake Erie and 131 wetlands in Lake Ontario decreased with decreasing water levels due to decreasing number of marsh-dependent species in Lake Erie and perhaps also in Lake Ontario. The average magnitude of the decrease in scores between extremely high and low water periods for wetlands with sufficient data was 15% in Lake Erie where water dropped 0.9 m on average (n = 11 wetlands) and 18% in Lake Ontario where water dropped 0.5 m (n = 7). Scores in Lake Erie increased with increasing Typha due to increasing numbers of marsh-dependent species and decreased with increasing Phragmites due to increasing numbers of generalist species. The opposite was observed in Lake Ontario, perhaps due to denser Typha and sparser Phragmites. Scores were explained by the naturally fluctuating water levels of Lake Erie, which favored Phragmites expansion and the regulated water levels of Lake Ontario which promoted Typha expansion. Scores were influenced by fluctuating water levels and associated changes in emergent vegetation. Inter-annual water level fluctuations should be considered when interpreting any indicator of wetland health that is based on marsh-dependent bird species.     

地下水位波动带内滨海软土性状研究进展

针对沿海城市地下水位波动带内的软土在饱和与非饱和状态之间交替转化的特点,通过分析国内外有关地下水位波动引发地面沉降以及地面沉降间接造成相对海平面上升等的研究现状,提出：探讨地下水位波动及工程施工荷载作用下非饱和软土的变形强度规律,揭示软土中孔隙水在减饱和－增饱和反复过程中的激变、转化和迁移机制,以及建立反映地下水渗流与荷载变化的非饱和软土固结沉降理论计算方法,是今后研究工作的发展方向,并提供了可行的技术研究思路与方法。     

Rapid Plant Community Response to a Water Level Peak in Northern Lake Huron Coastal Wetlands

Aquatic plants were sampled in five coastal wetlands of northern Lake Huron during July 1996, 1997, and 1998. Mean annual water levels of Lake Huron changed during this period from 176.37 m (below the long-term average) in January 1996 to above average water levels of 176.83 m in July 1996 to 177.19 m in July 1997 and then declined to 176.88 m by July 1998. Boundaries of plant zones as indicated by distribution of the 1–3 dominant species along permanently established transect points across the wetland did not shift spatially over this 3-year period. Instead, relative abundance (percent of total stems per three 0.25 m² quadrats per plot) and presence/absence of plant species responded individually to water level changes within major zones. In 1996, the first season sampled, the wet meadow had recently been inundated by rising water level. In 1997, after more than a year of above average and rising water levels, emergent stem densities were reduced in the Carex/Calamagrostis (sedge/blue-joint) dominated wet meadow and mixed transition sedge, narrow-leafed cattail, and hardstem bulrush (Carex, Typha angustifolia, and Schoenoplectus acutus) dominated zones compared to stem densities in 1996. Stem densities remained low in 1998, even though water levels dropped 31 cm from 1997 levels. The relative dominance (% of stems/3 quadrats/plot) and presence/absence of some plant species changed rapidly in the wet meadow zone in response to increases in water levels in 1997 and to decreases in water levels in 1998. In contrast, changes in emergent species were minimal in the deeper emergent zone dominated by hardstem bulrush. We conclude that temporary flooding and drying in response to water level changes are critical to maintaining a diverse arrray of plant species in the wet meadow zones of these marshes. Furthermore, short-term water level changes do not affect the relative spatial position of major plant zones within the marsh nor the relative abundance of emergent species in the deepest zone.