江苏里下河不同湿地植被地下水水位动态及影响因素

[目的]了解水资源丰富的里下河平原典型淡水湿地植被地下水水位的动态变化特征及主要影响因素,为该区淡水湿地植被的恢复和保护提供参考依据。[方法]以江苏省里下河平原两种典型淡水湿地植被(池杉针叶林和杨树阔叶林)为研究对象,分别布设2个地下水水位观测井,并对井中地下水水位动态进行长期观测,分析其月际和季节动态变化特征;同时采集2016年9月至2017年8月1个水文年的降水量和气温数据,分析地下水水位动态变化与气温和降水量变化的相关性。[结果]表明:两种典型淡水湿地植被地下水水位的动态变化存在显著的差异,池杉林几乎全年淹水,其月均地下水水位大于杨树林,而杨树林月际间地下水水位变化幅度相对较大,表现出季节差异;从季节动态看,池杉林和杨树林夏季的地下水平均水位相对于其他季节均明显要低。两种淡水湿地森林地下水水位的变化受降水量影响程度不同,杨树林地下水水位月动态表现出滞后于降水量变化约1个月,而这种滞后性未体现在池杉林中。杨树林和池杉林地下水的月均水位与月均气温间均呈现出极显著的负相关关系。[结论]不同淡水湿地森林的地下水水位动态具有不同特征,受环境因素的影响程度也有差异。在水资源丰富的里下河平原,降水量大小并不是影响该区淡水湿地植被地下水水位动态变化的关键因子,而气温则是主要影响因素。     

氢氧稳定同位素在淡水湿地森林水文过程研究中的应用

湿地森林在蓄洪防旱、净化水质等方面对区域水文过程起着重要的调控作用。以往对于淡水湿地森林水文的研究多集中在运用传统水文学方法研究单一水文过程,很少将各水文过程作为一个整体来研究,且各个过程对降水截留效应的影响程度也未全部量化。而利用水分子中天然存在的氢氧稳定同位素作为示踪剂可综合反映并量化植被和土壤对降水的截留能力。文中综述湿地森林对水文过程调控作用的国内外研究概况,探讨氢氧稳定同位素技术在湿地森林水文研究中的进展,包括大气降水、林冠穿透水、降雨径流、土壤水、地下水、蒸发水、植物水的水分来源及各水体的转化关系等。在全球变化背景下,运用氢氧同位素技术系统定量地分析降水在生态系统水文过程的分配比例对于揭示湿地森林植被结构对水文过程的调控机制等具有重要意义,同时也可为建立淡水湿地森林植被恢复模式和制定保护策略提供参考。     

草海国家级自然保护区植被恢复与重建初探

文章分析了草海自然保护区植被的生境、现状和演替规律,从恢复生态学原理出发,以水热等气候因子所决定的植被生物地带性为科学依据,提出以人工造林和封山育林等措施恢复与重建森林植被,以政策措施、生物措施和工程措施等恢复与重建湿地植被。     

论森林、淡水与湿地——以福建省为例

针对森林生态系统的作用、功能,结合福建省的山地森林,与流域淡水及湿地中的水源水质的密切关系,提出:要保护好森林资源,以及流域内的淡水和湿地;要从系统整体性出发,防范森林退化、破坏,以及流域内的淡水与湿地的破坏与污染问题。     

滨海盐碱湿地不同恢复区域的植被特征分析

在黄河三角洲滨海盐碱湿地黄河堤坝两侧选择了3个不同恢复区域的植被进行了调查,通过分析比较这3个区域植被分布的种类、特征、多样性和生物量等指标表明,充足的淡水(主要为黄河水)补给可使物种多样性增加,群落演替加快。     

乌溪江国家湿地公园湿地植被调查及保护措施

浙江衢州乌溪江国家湿地公园湿地为森林生态系统所涵养,湿地植被类型相对比较丰富,但其群落较破碎,片段化明显.据调查,有湿地维管束植物369种,隶属于93科254属,其中蕨类植物18科23属31种(含种下等级,下同),裸子植物1科2属3种,被子植物74科229属335种.湿地植被可划分为6个类型43个群系.简要分析了湿地保护保育中存在的问题,并提出了加大宣传教育力度、加强湿地植被恢复及其演替规律监测研究、建立健全湿地保护保育管理机制等建议     

国家生态红线是维护国家生态安全的底线

林地和森林红线。全国林地面积不低于46.8亿亩,森林面积不低于37.4亿亩,森林蓄积量不低于200亿立方米。划定依据主要是《中共中央、国务院关于加快林业发展的决定》。湿地红线。全国湿地面积不少于8亿亩。划定依据主要是第二次全国湿地资源调查成果。荒漠植被红线。全国治理宜林宜草沙化土地、保护恢复荒漠植被不少于56万平方公里。划定依据主要是《国务院关于进一步加强防沙治沙工作的决定》。     

塞罕坝七星湖湿地植被研究

塞罕坝七星湖湿地具有3个显著特征,一是分布海拔高并为森林生态系统所涵养;二是特殊的森林-草原过渡带;三是该湿地类型孕育了特殊的湿地植被和物种。据研究,七星湖湿地分为3个植被类型13个群系。文章介绍了七星湖湿地独特的植被特点及湿地形成原因,旨在说明七星湖湿地作为塞罕坝湿地的典型代表,具有重要的生态保护价值和科学研究价值。     

湖南衡山萱洲国家湿地公园植被调查研究

为调查湖南衡山萱洲国家湿地公园内植被分布情况,为生物资源的科学保护管理提供参考依据。通过标准地调查与样线调查相结合方法可知,湿地公园内植被类型可划分为57个群系,其中森林植被划分为11个群系,湿地植被46个群系,群系类型多样,物种组成丰富,森林植被表现出中亚热带常绿阔叶林的特点,湿地植被是衡山县、衡东县的典型代表。     

基于河流型湿地生态修复的湿地公园生态修复研究——以长白山碱水河国家湿地公园为例

近年来,随着生态文明建设的战略地位愈发凸显,湿地生态修复与保护也成为研究热点。为改善长白山碱水河国家湿地公园生态环境,修复受损湿地,以碱水河国家湿地公园生态环境修复工程为例,通过解决湿地生境受损、森林和湿地植被退化等问题,旨在为国家湿地公园的湿地生态修复、生境恢复重建方面提供参考。     

The response of planted trees to vegetation zonation and soil redox potential in created wetlands

We examined interrelationships among natural vegetation zones, soil redox potential (Eh), and metrics of tree seedling performance (i.e survival, growth, and photosynthesis) for planted Fraxinus pennsylvanica, Acer saccharinum, Quercus palustris, and Quercus bicolor at two created perched wetlands (two years and five years old) in Michigan, USA. Vegetation zones apparently associated with hydrology were fully developed at both sites. Wetland zones always had lower mean Eh than upland zones, indicating mostly anaerobic and aerobic root environments, respectively. Eh values for transition zones were similar to aerobic upland zones at the five-year-old site, and changed from anaerobic to aerobic conditions over the growing season at the two-year-old site. At the five-year-old site, transition zone trees of all species generally had greater height growth, survival, and were less likely browsed by deer than upland trees. They also had much greater survival and endured shorter periods of anoxia stress than wetland trees. Photosynthesis was positively related to survival and Eh, suggesting that unfavorable carbon balance may help explain low survival in the anoxic wetland zone. Management implications include: (1) vegetation zonation is a good indicator of wetland hydrological factors important to planted tree performance; (2) targeting developed transition vegetation zones for tree planting could increase the success and efficiency of efforts to create forested wetlands; and (3) transition zones extended over only a 9.3 cm vertical elevation gradient, indicating the importance of precise grading when creating perched forested wetlands.     

嫩江流域受损湿地修复技术研究

基于嫩江流域受损湿地的现状,根据嫩江流域典型的3种不同湿地类型开展了以下几个方面的研究:嫩江流域不同湿地类型土壤理化性质分析、嫩江流域湿地典型植被分布规律、嫩江流域湿地退耕还湿与植被恢复技术试验等,通过试验研究解决了嫩江流域湿地退化、湿地修复重建等方面存在的问题。     

盐城滨海湿地植被恢复原则与技术概述

盐城滨海湿地是江苏省重要的滩涂湿地,在珍稀动植物保护中发挥着重要的作用.由于滩涂湿地的过度开发利用,盐城滨海湿地正面临严重的破坏,生态功能逐渐退化.湿地植被恢复是退化湿地生态修复最重要的措施之一.该文基于盐城滨海湿地的退化现状和退化原因,提出了盐城滨海湿地植被恢复需遵循的生态学原则,包括:生态系统完整性、自然演替、优先...     

Characteristics of small headwater wetlands in second-growth forests of Washington, USA

In 2002, we initiated a study to clarify the response of headwater catchments to logging on timberlands in the Coast Range of Washington, USA. Most of the predominantly first-order streams studied (summer low flows typically < 0.3 L s⁻¹) were hydrologically complex, consisting of a main surface channel connected to multiple, small wetlands. To better understand the forest management implications of headwater systems with two surface hydrology components of potentially differing areal extents (i.e., broad wetlands and narrow, channelized flow), we examined in more detail the wetlands associated with 30 headwater channels. On average, 2.3 wetlands occurred per channel. All 68 surveyed wetlands were, individually, smaller than 0.1 ha, which is a minimum survey-and-manage size criterion for forested wetlands in use in the Pacific Northwest. Seventy-nine percent of the wetlands surveyed by the full-triad method met regional wetland triad criteria for wetland delineation (qualifying wetland soils, hydrology, and vegetation indicators). These headwater wetlands were associated with several landscape variables: (1) northerly-facing catchments, (2) perennial surface water, and (3) down, channel-associated large wood originating from adjacent riparian forest. Our results show that small forested wetlands are quite common and that the surface area of small wetlands can rival the surface area of the associated first-order streams. This initial effort to quantify characteristics of small headwater wetlands suggests small wetlands could dominate or influence headwater surface area processes including those associated with stream responses to disturbances such as logging.     

Use of hummocks and hollows by trees in tidal freshwater forested wetlands along the Savannah River

Tidal freshwater forested wetlands occupy a relatively narrow range, occurring where wind and lunar tides interact with coastal river systems, causing freshwater flooding onto the floodplain. A prominent component of this wetland type is hummock and hollow microtopography. Tidal freshwater forested wetlands along the Savannah River were differentiated into backswamp and streamside areas, and the degree to which trees occupied hummocks and hollows were compared at three scales: landscape (backswamp vs. streamside), tree community, and species (within community). The community- and species-level analyses were extended to determine whether trees were using either hummocks or hollows in a nonrandom manner. Trees in the backswamp setting were found to use hummocks more than trees in the streamside setting. At the community scale, three of the five treatment groups investigated differed based on the degree to which trees on hummocks outnumber trees in hollows. Further examination of microtopography usage confirmed that hummocks are used significantly more than hollows in two communities, both of which are located in the backswamp setting. Though no tree community used hollows significantly more than hummocks, species-level analyses confirmed that, within a specific tree community in the streamside setting, alder (Alnus serrulata [Ait.] Willd.) is found more in hollows than on hummocks. Fourteen different species between the two communities in the backswamp setting are found on hummocks more than in hollows, and only one species, sweetgum (Liquidambar styraciflua L.), is found more on hummocks than in hollows in the tree community in the streamside setting.     

桥山林区矿山植被保护与恢复技术的探讨

通过对桥山林区矿山范围内生态环境破坏现状和相同生态区位废旧矿山植被恢复情况进行调查分析,提出了黄陵矿区矿山植被保护与恢复技术措施,为保护当地生态环境提供技术支撑。     

Floristic composition and soil characteristics of tropical freshwater forested wetlands of Veracruz on the coastal plain of the Gulf of Mexico

We studied the influence of geomorphological setting and soil properties on the vegetation structure, composition and diversity of five forested coastal wetlands in Veracruz on the Gulf of Mexico. These swamps are located on floodplains and in dune depressions. We recorded 109 woody and herbaceous species. The most frequent species were the trees Pachira aquatica, Annona glabra, Diospyros digyna and Ficus insipida subsp. insipida, the lianas Dalbergia brownei and Hippocratea celastroides and the hemi-epiphyte Syngonium podophyllum. The Shannon-H diversity index varied from 2.659 to 3.373, density from 1750 to 2289 stems ha⁻¹ and basal area from 32.7 to 76.42 m² ha⁻¹. The classification analysis defined two groups: one corresponded to forested wetlands along the floodplain (Apompal, Cienaga, Chica) and the other included Mancha and Salado, in dune depressions. PCA ordination of soil parameters during the rainy season explained 67.0% and during the dry season 69.1% of the total variance. In the rainy season Mancha and Salado samples remain close together because they have lower Mg, Na, K, % Total C and % Total N values. Apompal and Chica samples remain close to each other because of their high levels of % Total C, % Total N, Mg, Na and high soil water content. Cienaga samples are separated from the others because of high values of P, Ca and Eh as well as high water levels. In general, soil parameter ordination during the dry season showed that redox potential, P, water level and water content decreased in the forested wetlands and Na values increased in Chica. The soil textures identified were clay, sandy clay loam, sandy loam and clay loam; clay texture dominated alluvial processes in the floodplain (e.g., Cienaga). The forested wetlands in the floodplains had similar vegetation and the same happened in the dune depressions but soil characteristics were more variable in both cases. Plant diversity in floodplains tends to be relatively high, and the presence of adjacent tropical forests probably increases its richness, except in cases in which there are stressing factors, such as salinity. The forested wetlands studied showed dominant floristic elements, which extend north into Florida such as A. glabra and Ficus aurea. Other dominant elements such as P. aquatica are also found in Central and South America. The forested wetlands studied are subjected to continuous deforestation to transform the land into farming or ranching activities, this being a common practice throughout the distribution range of these forests.     

贵州草海湿地现状与生态恢复对策

贵州草海是我国亚热带高原湿地生态系统的典型代表;阐述草海湿地基本特征,分析湿地面临的主要问题,从草海河口湿地、湖泊与沼泽湿地冰污染处理、面山植被以及湿地生态景观等方面,提出生态恢复对策。     

毛乌素沙地不同治理措施植被恢复效果分析

从群落数量结构与干物质生产方面对刘家窑头流域赵家塘不同治理措施下的植被恢复效果进行初步分析.结果表明林草复合措施植被恢复效果最好,灌木林地植被恢复优于乔木林地,杨树纯林地效果较差;草方格固沙能使植被迅速恢复;喷撒化学固沙剂对迎风坡植被恢复的效果较为显著.