A geospatial assessment on the distribution,condition, and vulnerability of Wyoming's wetlands

Wetlands serve critical functions including natural flood control and providing wildlife habitat, yet despite these values they remain highly threatened systems. Here we present a landscape-scale geospatial assessment of wetlands in Wyoming. Areas containing high densities of wetlands were identified and mapped, and wetland complexes were quantified as a function of their biological diversity, protection status, susceptibility to climate change, and proximity to sources of impairment. Our results indicate there are 280591 wetlands in Wyoming, totaling 371758 surface hectares, and 222 wetland complexes. The majority (67%) of wetlands are classified as temporary. Low elevation wetland complexes are the least protected, in the poorest current condition, and the most vulnerable to future land use changes. This fundamental information will provide a tool decision-makers can use to more effectively allocate limited resources to conserve, manage, and restore Wyoming's wetlands.     

黄河流域湿地水鸟多样性保护对策

黄河是中华文明的发源地, 被誉为母亲河, 是两岸社会经济发展的保障, 切实保护好黄河流域湿地生态系统, 事关中华民族伟大复兴的千秋大计。黄河流域湿地总面积为391万ha, 其中80.4%分布在上游, 中游和下游分别仅12.5%和7.1%。黄河流域是东亚-澳大利西亚候鸟迁徙路线和中亚候鸟迁徙路线上水鸟的关键栖息地, 一些迁徙水鸟最关键的栖息地均分布在黄河流域, 如黑颈鹤(Grus nigricollis)、白鹤(G. leucogeranus)、丹顶鹤(G. japonensis)、斑头雁(Anser indicus)、大鸨(Otis tarda)、东方白鹳(Ciconia boyciana)、大天鹅(Cygnus cygnus)、疣鼻天鹅(C. olor)、青头潜鸭(Aythya baeri)等。尽管黄河流域湿地提供的水资源仅占全国的2%, 但维持着全国12%的人口饮水安全和15%的耕地用水, 湿地生态系统的脆弱性较高。截至2017年底, 黄河流域已建立各类湿地自然保护地230处, 其中国家公园2处、国家级自然保护区9处、地方级自然保护区68处、国家湿地公园145处、省级湿地公园6处, 湿地保护率达到65%, 高于我国湿地保护53%的平均水平。然而, 流域尺度现有水鸟生物多样性保护仍然面临不少挑战, 包括全球气候变化、水资源过度利用、水环境污染、栖息地丧失等。为此, 我们提出了建立以国家公园为主体的湿地保护地体系、开展濒危候鸟栖息地修复和强化黄河流域综合管理的体制机制建设等建议。     

时空变化视角下北京市湿地优先保护格局

气候变化通过改变湿地水文过程等影响湿地的空间分布,城市化进程加剧了湿地破碎化程度并导致湿地生境退化,构建连续的湿地生态保护网络体系有利于应对气候变化和城市发展带来的负面影响、提高生物多样性保护水平。北京市现有湿地空间分布呈现斑块面积小、破碎化程度高等特点,为优化湿地保护区格局并应对气候变化和城市发展对北京市湿地生物多样性的影响,基于系统保护规划方法,以Marxan作为空间优化模型,结合PLUS模型和MaxEnt模型,模拟预测北京市湿地优先保护格局、识别湿地保护空缺并构建湿地分级保护区格局。研究表明:2020年北京市湿地存在80.15km²的保护空缺、2035年和2050年优化后湿地保护区占比分别为87.54%和85.95%,在满足本研究预设的生物多样性保护目标的前提下符合北京市湿地保护规划对湿地保护率的要求。为最优化资源分配,综合时空变化对湿地保护区空间分布的影响,构建了湿地分级保护区格局,将湿地保护区分为湿地永久保护区、湿地一级临时保护区和湿地二级临时保护区三个等级,以期为北京市分期建设湿地保护区、优化湿地生态保护网络体系和保护湿地生物多样性提供依据。     

Species richness and conservationof Namibian freshwater macro-invertebrates,fish and amphibians

Namibia is an arid country but has a diverse array of wetland habitats ranging from ephemeral water bodies and rain-pools, artesian springs supporting small perennial pools and streams, to the large perennial rivers of the north-east with their associated floodplains. These rivers drain wetter areas north of Namibia and contribute many tropical species to Namibia's wetlands. There are 778 described species of macro-invertebrates representing eight phyla with 81 endemics. Many invertebrates still have to be identified or described but presently the greatest endemism occurs among the Ostracoda (18 species), Coleoptera (17), Diptera (14), Anostraca (six) and Amphipoda (five species). In total, Namibia has 50 species of frog with three endemics. No caecilians or salamanders occur in Namibia. There are 114 species of freshwater fish with five endemics. Most Namibian wetlands occur outside protected areas. Over-exploitation of wetland resources and flow regulation are currently major threats, but new environmental legislation being formulated is based on the goal of sustainable use.     

Identifying nascent wetland forest conversion in the Democratic Republic of the Congo

Wetlands cover large areas in the Democratic Republic of the Congo. However, their extent and distribution have not been accurately mapped. While wetland forests remain largely undisturbed, increasing threats by anthropogenic activities have been observed in areas with high population density per arable or exploitable land. The scarcity of terra firma forests in some territories of the Democratic Republic of the Congo has forced local communities to develop cropping methods that allow for cultivation in periodically flooded areas. Assessing wetlands extent and status is critical for long term conservation of these highly vulnerable ecosystems. In this study, we use multi-source and multi-resolution optical and radar remotely sensed data and elevation derived indices to map the wetlands of the Democratic Republic of the Congo. Results showed that wetlands are a significant part of the landscape in the country, covering an estimated 440,000 km² or 19.2 % of the total country area. By combining the wetlands map with a previously produced land cover depiction of the Democratic Republic of the Congo, a map including forested wetlands as a thematic class was derived. We investigated whether high terra firma population density and low percent remaining terra firma forest are related at the lowest administrative level (Sector); specifically, we tested these two variables as predictors of wetland forest cover loss. A polynomial regression relating population and primary terra firma forest to wetland forest cover loss yielded an r ² of 0.76, illustrating a nascent and significant land cover change dynamic. Areas most at risk for future wetland forest loss lie in the western Cuvette, and include (north–south) the Sud-Ubangi, Mongala, Equateur and Mai-Ndombe Districts. By quantifying available upland forest resources and overlaying with population density, it was possible to identify stressed areas inside of the forest domain (traditionally known for having generically high levels of forest resources). Results illustrate the need for addressing issues of wetland forest management and protection in the Democratic Republic of the Congo, especially where increasing populations are exhausting primary terra firma forest resources.     

Functioning and dynamics of wetland vegetation of Lake Victoria: an overview

The aquatic macrophytic vegetation constituting the wetlands situated along the coast of Lake Victoria provides valuable services to both local and regional communities as well as an important ecological function through the transition between terrestrial and aquatic ecosystems. The wetland vegetation is typically rooted in the substrate on the landward side of the lake, but forms a floating mat towards the middle of the wetland and at the wetland/lake interface. Cyperus papyrus and Miscanthidium violaceum vegetation typically dominate the permanently inundated wetland areas along most of the shores of Lake Victoria. Due to the prevailing climatic and hydrological catchment conditions, these macrophytic plants (papyrus in particular) tend to exhibit high net productivity and nutrient uptake which strongly influences both wetland status and lake water quality. In addition, these wetlands provide important economic livelihoods for the local populations. The integrity and physical structure of these wetlands strongly influences their associated mass transport mechanisms (water, nutrients and carbon) and ecosystem processes. Wetland degradation in Africa is an increasing problem, as these ecosystems are relied upon to attenuate industrial, urban and agricultural pollution and supply numerous services and resources. In an integrated project focused on the wetlands of Lake Victoria, the ecological and economic aspects of littoral wetlands were examined and new instruments developed for their sustainable management.     

基于遥感的湿地景观格局季相分析

以中国东北地区三江平原北部为研究区域,利用2012年多季相遥感影像作为数据源,结合野外调查数据,应用面向对象的分类方法,根据影像的物候、时相等特征,提取不同月份的湿地信息,进行景观格局季相分析。结果表明:(1)研究区湿地面积、类型格局在同一年不同季节不同月份会有不同幅度的变化,总体呈现缓增骤减的态势。湿地主要分布在低洼地区,主要湿地类型为草本沼泽,其次为河流,其他湿地占总面积比例较小。(2)研究区各阶段湿地都有转化,主要发生在湿地和非湿地之间,多数表现在草本沼泽和草地之间的转化。(3)湿地分布和湿地转化面积主要集中在低海拔区域和低坡度区域,其中海拔100 m和坡度5°以下范围内的湿地分布面积和湿地转化面积占湿地总面积及湿地转化面积的绝大部分。(4)年内季节性湿地转化与降水、温度和湿地植被物候关系密切。     

Reduction of avian diversity in created versus natural and restored wetlands

Natural wetland ecosystems continue to suffer widespread destruction and degradation. Many recent studies argue that artificial or restored wetlands compensate for wetland loss and are valuable for waterbird conservation. However, detailed comparisons of the value of natural, artificial and restored wetlands are lacking. Our aim was to assess if the restoration or creation of wetlands can fully compensate for the loss of natural wetlands for waterbirds. We compared the waterbird communities in a set of 20 natural, restored and artificial wetlands, all of which are considered important for waterbirds and are located within the same protected area (Doñana Natural Space, south‐west Spain). We used different measures of diversity, including phylogenetic relatedness, and the proportion of threatened species at national, European and international levels. We found that artificial wetlands have consistently lower value than restored and natural wetlands, with little difference between the latter two. Natural wetlands are essential for conserving diversity across the tree of life and for threatened species, but restored wetlands can be of similar value and can assure maintenance of key ecological processes. Thus, when economic costs per unit area are similar, resources for wetland conservation are better invested in restoration projects than in wetland creation, and caution is required when suggesting that artificial wetlands compensate for the loss of natural wetlands.     

浙江秀山岛湿地生态系统初探

秀山岛位于东海舟山渔场海域,岛上有大片的湿地资源分布,其滨海部分与舟山渔场的生物资源特别是渔业生物资源密切联系,具有罕见的海岛特色。海岛的特殊地理位置为秀山岛湿地赋予了独特的生态特征。秀山岛湿地内动植物资源丰富,生物多样性高,共有植物种类300余种,栖息的鸟类共有26个科108种,包括国家一级保护动物东方自鹳（Ixobrychus minutus）。还有国家二级保护动物獐（Hydropotes inermis）等珍贵动物自然栖息。秀山岛湿地包括潮下带湿地（浅海湾）、潮间带湿地（泥滩、芦苇丛）、潮上带湿地（咸水沼泽、半咸水沼泽）、异化湿地（盐田、养殖池、稻田）等几个紧密联系的部分。具有多方面的生态功能。由于对湿地的生态功能重视不够,湿地生态系统破碎化严重。目前在秀山岛湿地已经建立了湿地自然保护区,湿地生态系统得到了较好的发展。     

A comparison of wetland characteristics between Agricultural Conservation Easement Program and public lands wetlands in West Virginia,USA

In West Virginia, USA, there are 24 conservation easement program wetlands enrolled in the Agricultural Conservation Easement Program (ACEP). These wetlands are located on private agricultural land and are passively managed. Due to their location within fragmented agricultural areas, wetlands enrolled in ACEP in West Virginia have the potential to add wetland ecosystem services in areas that are lacking these features. We evaluated ACEP wetlands compared to reference wetlands on public land in West Virginia by using surrounding land cover, vegetative cover, and wetland features and stressors such as the presence or absence of erosion, upland inclusion, algal mats, and evidence of impacts from the surrounding landscape as surrogate measurements of wetland function on 13 ACEP wetlands and 10 reference wetlands. ACEP wetlands had higher percentages of tree coverage and a higher proportion of agricultural land in the areas immediately surrounding the wetland. Reference wetlands had higher percent coverage of emergent vegetation and had a higher proportion of forest in the immediate landscape. Our findings suggest that ACEP wetlands provide valuable early successional and forested wetland cover in a state that is largely forested. Because of this, it is important to maintain and even expand ACEP in West Virginia to continue providing a valuable source of early successional wetland habitat.     

Spatial patterns in small wetland systems: identifying and prioritising wetlands most at risk from environmental and anthropogenic impacts

This study establishes whether analysing the distribution patterns of wetlands could identify key systems that would focus conservation and management decisions, without site-specific data which requires significant logistical and financial resources. In the proposed approach, key wetlands at-risk were identified based on their position in the landscape, through the use of probability modelling and least-cost analyses. The research was based in a semi-arid part of the Eastern Cape, South Africa. The study area has aseasonal rainfall, different land-use zones and an existing spatial dataset, providing an ideal setting to test this method. Wetlands were highly clustered, with higher densities recorded in the south and along larger rivers. Areas that have more-suitable environmental conditions for wetlands were mapped—showing similar patterns to known dense wetland areas. In total, 89 systems were identified as very high-risk, and 414 wetlands were high-risk, to environmental and anthropogenic changes. Seven focal zones were selected by incorporating wetland clusters/hotspots. These zones should be the focus for further research and management that would assess the surrounding environment and the potential effects of land-use or climate changes, and policy adaptation. In summary, this study successfully illustrated the importance of adapting different spatial analytical methods in wetland research, and that desktop studies can be used to focus conservation and management efforts over larger areas.     

Field-based assessment of wetland condition,wetland extent,and the National Wetlands Inventory in Kentucky,USA

The economic and ecological importance of wetlands is well documented, but there are few studies that have assessed wetland condition and extent for the United States. Many states, including Kentucky, have had no statewide field evaluation of wetlands of any kind. The National Wetland Inventory (NWI) is the largest database for mapped wetlands in the United States and the most comprehensive source of wetland information for Kentucky, but its value for determining wetland condition is limited. Therefore, our objectives were to document wetland extent and condition and assess the agreement between the NWI and field-based wetland characteristics in Kentucky. We conducted field and remote-sensing based assessments of 352 wetlands across the state. NWI-mapped and field-assessed wetlands had similar large-scale patterns; however, for individual wetlands, classification often disagreed. Based on our wetland assessment method, wetlands appear to be of moderate condition, although we found differences among basins, dominant vegetation types, and landscape positions and much variation as many sites scored very low and high. Our findings support previous work showing that rapid assessments are valuable for determining wetland condition for ambient monitoring and other applications. Also, our results provide the foundation for future status and trends studies and suggest an urgent need to update the NWI in Kentucky and elsewhere. We suggest that the NWI could be improved by using newer technology that increases wetland mapping accuracy and including predictions of wetland condition using the enhanced NWI approach.     

泡桐属(Paulownia)花粉形态学的初步研究

泡桐属(Paulownia)花粉,均为近球形,具3(拟)孔沟,外壁外层有清楚的异胞网状雕纹,沟界极区明显。这些共同特征,说明泡桐属是一个种间亲缘极近的自然的属;其萌发孔类型,可作为泡桐属归入玄参科的证据之一。通过花粉形态的比较,对兰考泡桐、宜昌泡桐和建始泡桐的分类地位,提出了论证。     

湿地退化研究进展

受经济发展、城市扩张、气候变化的影响,湿地退化已经成为全球性现象,是当前国际湿地科学前沿领域的热点。从湿地退化标准、退化特征、退化分级、退化过程、退化机理、退化监测体系、退化评价指标与指标体系、退化监测新技术及其生态恢复理论与技术9个方面系统地介绍了当前湿地退化研究进展。结果表明湿地退化过程、退化机理、退化评价指标体系和退化湿地监测、恢复与重建研究是当前研究的重点,在未来相当长的时间内,全球气候变化、湿地退化的微观过程与机理、湿地生态系统的可持续利用将会是重要的研究方向。最后就我国当前湿地退化研究存在的问题进行了分析,并提出近期湿地退化研究亟待开展的11项研究工作,供我国湿地退化研究工作者参考。     

长沙城市斑块湿地资源的时空演变

利用GIS技术,对长沙市1955、1972和1990年地形图湿地数据及2007年长沙市湿地资源普查数据进行提取和分析,选取最具代表性的斑块湿地作为研究对象,从时间与空间、动态与静态、规模与填埋等视角,研究50年来城市斑块湿地生态系统各层次要素的时空演变过程和变化规律.结果表明:(1)时间层次上,长沙城市斑块湿地总面积呈现先增后减、总体增加的态势;斑块湿地面积变化幅度不断加大,速率逐步加快;(2)规模层次上,面积在32 hm2规模以下的斑块湿地呈增加态势,32 hm2规模以上斑块湿地呈减少态势;(3)动态空间层次上,被填埋斑块湿地的比例在建成区和郊区呈相反的演变结果;(4)静态空间层次上,斑块湿地密度在建成区范围和郊区范围演变结果相背.研究显示,伴随着城市化进程,不同时间尺度、不同规模尺度、不同空间属性、不同空间状态的城市斑块湿地常常呈现差异很大、甚至是截然相反的演变结果;无论是动态空间还是静态空间,建成区与郊区的空间分界线往往是城市斑块湿地演变态势的分水岭.     

Vegetation Similarity and Avifaunal Food Value of Restored and Natural Marshes in Northern New York

Measuring the success of wetland restoration efforts requires an assessment of the wetland plant community as it changes following restoration. But analyses of restored wetlands often include plant community data from only one time period. We studied the development of plant communities at 13 restored marshes in northern New York for 4 years, including 1 year prior to restoration and 3 years afterwards. Restored wetlands ranged in size from 0.23 to 1.70 ha. Four reference wetlands of similar basin morphology, soil type, and size (0.29–0.48 ha) that occurred naturally in the same area were studied as comparisons. Dike construction to restore hydrology disturbed the existing vegetation in some parts of the restored sites, and vegetation was monitored in both disturbed and undisturbed areas. Undisturbed areas within the restored sites, which were dominated by upland field grasses before restoration, developed wetland plant communities with lower wetland index values but comparable numbers of wetland plant species than the reference wetlands, and they lagged behind the reference sites in terms of total wetland plant cover. There were significantly more plant species valuable as food sources for wetland birds, and a significantly higher percent cover of these species, at the undisturbed areas of the restored sites than at the reference wetlands. Areas of the restored sites that were disturbed by dike construction, however, often developed dense, monospecific cattail stands. In general, the plant communities at restored sites became increasingly similar to those at the reference wetlands over time, but higher numbers of herbaceous plants developed at the restored sites, including food plants for waterfowl, rails, and songbirds. Differences in shrub cover will probably lessen as natural recolonization increases shrub cover at the restored sites. Natural recolonization appears to be an effective technique for restoring wetlands on abandoned agricultural fields with established plant cover, but it is less successful in areas where soil has been exposed by construction activity.     

《生物多样性公约》海洋生物多样性议题的 谈判焦点、影响及我国对策

海洋和沿海生物多样性保护和可持续利用等问题是《生物多样性公约》谈判的重要领域。本文梳理了历次缔约方大会的谈判进程, 认为主要焦点议题包括: (1)应对人类活动和全球气候变化对海洋和沿海生物多样性的影响; (2)海洋和沿海生物多样性保护和可持续利用的工具; (3)海洋保护区及具有重要生态或生物学意义的海域。这些议题的讨论将影响包括全球海洋保护区建设在内的海洋生物多样性保护进程, 也将影响全球海洋生物多样性保护国际制度的建设, 以及沿海国家的社会经济。我国应加强履约谈判的技术支持, 加快涉海相关问题研究, 积极参与相关国际谈判, 并大力宣传我国经验。     

Vulnerability, livelihood assets and institutional dynamics in the management of wetlands in Lake Victoria watershed basin

This paper uses data from 600 households in the Lake Victoria watershed in Tanzania, Kenya, and Uganda to analyze the effects of vulnerabilities and shocks on the management and exploitation of wetlands within the context of agricultural activities and high poverty levels. A multinomial logit model is used to determine variables that influence the perception of wetlands degradation, while a tobit model is used to establish the determinants of willingness to pay for wetland conservation and the imputed value of wetland product extracts. The model results show that although the perception of wetland degradation is modest, it is influenced by attributes of social capital. Variables such as floods, diseases and droughts significantly influence the households’ willingness to pay for wetland conservation. Land size and ownership, education level and household size all influence households’ likelihood to actively engage in wetland resource exploitation and willingness to pay for its conservation. The implications of these results hinge on measures that would moderate the effects of shocks, mobilize collective action, and improve physical infrastructure within the context of sustainable wetland resource use.     

Gap analysis of two savanna-type ecoregions: a two-scale floristic approach applied to the Llanos de Moxos and Beni Cerrado,Bolivia

The Beni savannas (locally referred to as pampas) is composed of two clearly differentiated ecoregions, the Llanos de Moxos (or Moxos) and the Beni Cerrado. Both tropical savannas are shaped to a greater (Moxos) or lesser (Beni Cerrado) by cycles of drought and flood and the labor of generation of farmers. It contains floristic elements of four biogeographic regions (Amazonian, Chaco, Cerrado and Chiquitana). However, in spite of their biological richness, they are little represented in the National System of Protected Areas (SNAP, in Spanish). By employing an ecoregion and sub-ecoregion approach, we examined the representation of both savanna-type ecoregions in the Departmental System of Protected Areas (SDAP, in Spanish), which includes national, departmental, municipal, and private protected areas. The study also enabled us to compare Bolivia’s newest ecoregion/vegetation zones maps as applied to the both savannas and to produce a sub-ecoregion map for the Beni department (northeastern Bolivia). Our results show that the Llanos de Moxos and the Beni Cerrado are found in protected areas of departmental and municipal level. Although they are still under-represented (mainly the Beni Cerrado), they have nonetheless important extensions inside these protected areas. A better representation of these zones would guarantee improved levels of protection of these unique ecosystems. On the other hand, our study shows the importance of the conservation-representation target relationships (sensu Rodrigues et al. 2004). This is the first time that this approach is used to examine gaps of floristic representativeness of savanna-type ecoregions showing that the traditional 10% minimal conservation target should be used with caution.     

三江平原典型环型湿地土壤-植被-动物系统的结构及功能研究

环型湿地是三江平原沼泽湿地的主要景观类型之一。由于微地貌的变化 ,形成了相应的高势能区和低势能区。随着势能的变化 ,形成了不同的水热分布带 ,因而也产生了不同的土壤、植物、动物的环型水平结构和垂直结构的特点。在水平结构上 ,环型湿地由中心向外缘 ,地势由低到高 ,水分由多渐少 ,温度由低到高分布。因此 ,也带来了土壤和动植物的变化 ,土壤由泥炭土向沼泽土和白浆土过渡 ;植物由沉水的小狸藻向浮水的漂筏苔草、挺水的大穗苔草 睡菜群丛、毛果苔草 -狭叶甜茅群丛、小叶章 -沼柳 -越菊柳以及外缘分布的蒙古栎 白桦岛状林发展。动物的水平结构也就有相应的变化。环型湿地每个水平分布带又都具有各自不同的垂直结构。环型湿地的特殊结构 ,使其有着巨大的储水功能和调节温度的功能。即使在高温干旱的季节 ,由于湿地表面的须根层有隔离的空间 ,阻止了温度的传导 ,减少了下层水的蒸发 ,在下层的泥炭中仍有大量的水分保持。同时 ,这里也是一个太阳能储存库和遗传基因库。深入了解环型湿地的结构与功能 ,对研究湿地生态系统的功能及其保护湿地 ,实现湿地资源的可持续利用都具有重要的意义