Forest Wetland Area and the Forest Sector Economy in the U.S. South

This article reviews current data on forest wetlands and their economic contributions in the South, ranging from Texas to Virginia. Based on USDA Forest Service Forest Inventory and Analysis (FIA) data, the wetland category comprised 17.7% of timber land area on all private and public lands in the South. This included 4.25 million ha of hydric sites;0.77 million ha mesic wet;9.55 million ha mesic, with only seasonal access;for a total of 14.57 million ha. The Natural Resource Inventory (NRI) for 2012 on private lands estimated that there were 14.71 million ha forested wetlands, which comprised 17.7% of all forested private forest area. The 2015 National Land Cover Data for the South estimated that there were 17.8 million ha of woody wetlands, which comprised 8% to 12% of the southern land area, and there were also 4.45 million ha of emergent herbaceous sites. About 10% of the southern timber forest sector would be based on harvests from wetland forests economy ($455 million per year), while the 17.7% of wetland land area would provide a proportional share of the annual nontimber forest products ($44 million) and payments for ecosystem services ($134 million). Wetlands also provide important nontimber forest products, and ecosystem services, which are beginning to develop active private and public markets.

Contribution of Sentinel-2/Landsat-8 OLI Images to Extracting Vegetation Cover and Wetlands Area in Urban Zones: Case of the Dakar Region (Senegal)

Urban areas house vegetation cover in several forms, fulfilling several ecological functions like thermal regulator, biodiversity, air quality, etc. However, their extent is often not very well known, especially in African cities, making it sometimes difficult to assess their real impact on the urban ecosystem functioning. This work aims to analyse the capacity of satellite sensors for mapping vegetation and wetlands in urban areas. The data produced by the MSI sensors of Sentinel 2 and OLI of Landsat-8 are used to identify and map the vegetation cover in the Dakar region through a supervised classification with the Support Vector Machine (SVM) algorithm. The results show that it is sometimes not very easy to analyse urban vegetation with high spatial resolution images (HRS) resulting from the configuration of the vegetation in an urban environment, sometimes characterized by isolated trees or small green spaces. This explains why Sentinel-2 data which spatial resolution of 10 meters gives a better result compared to Landsat-8 data which is 30 meters. However, a good rendering is noted for the vegetation around the wetlands area for the two sensors resulting from the high density and the size of the vegetated perimeters in this part of the capital. Overall, there is an underestimation of urban vegetation cover, particularly for Landsat-8. The use of very high spatial resolution images could be necessary to better assess the potential of satellite data for monitoring urban vegetation in Sahelian context.

Landscape planning and ecology construction of wetland comprehensive protected area system in the Sanjiang Plain

Wetland is one of the richest biodiversity areas in the earth. The main purpose of establishing wetland protected area is to protect biodiversity, and the protection of ecosystem diversity and landscape diversity is the key to protect biodiversity. In order to protect regional ecosystem and landscape, it is a good way to establish wetland comprehensive protected area which connected wetland nature reserves by habitat corridors. The Sanjiang Plain as a study area, its landscape evaluation index system on wetland protected area was studied, and some problems on landscape planning and ecology construction were further approached in this paper.It showed that establishing wetland comprehensive protected area is very important to protect regional wetlands, to maintain ecological balance, and to improve the sustainable development of agriculture and industry in this region.

Application of Lotus in Canal Wetland Landscape Area

The project of "Integration and Application of Lotus Opening Techniques in Zaozhuang Wetland Landscape Areas" was briefed, role and application of lotus in ecological restoration and protection of canal wetland park, maintaining ecological balance of canal wetland, protecting ecological functions of canal wetland, guaranteeing water quality of the canal and biodiversity of canal wetland, and promoting sustainable development of the ecosystem.

Stem and Total Above-Ground Biomass Models for the Tree Species of Freshwater Wetlands Forest, Coastal Areas and Dry Areas of Bangladesh: Using a Non-Destructive Approach

Biomass and carbon stock in a forested areas are now prime important indicators of forest management and climate change mitigation measures. But the accurate estimation of biomass and carbon in trees of forests is now a challenging issue. In most cases, pantropical and regional biomass models are used frequently to estimate biomass and carbon stock in trees, but these estimations have some uncertainty compared to the species-specific allometric biomass model. Acacia nilotica, Casuarina equisetifolia and Melia azedarach have been planted in different areas of Bangladesh considering the species-specific site requirements. While Barringtonia acutangula and Pongamia pinnata are the dominant tree species of the freshwater swamp forest of Bangladesh. This study was aimed to develop species-specific allometric biomass models for estimating stem and above ground biomass (TAGB) of these species using the non-destructive method and to compare the efficiency of the derived biomass models with the frequently used regional and pantropical biomass models. Four Ln-based models with diameter at breast height (DBH) and total height (H) were tested to derive the best fit allometric model. Among the tested models, Ln (biomass) = a + b Ln (D) + c Ln (H) was the best-fit model for A. nilotica, M. azedarach, B. acutangula and P. pinnata and Ln (biomass) = a + b Ln (D2H) was best-fit for C. equisetifolia. Finally, the derived best-fit species-specific TAGB models have shown superiority over the other frequently used pantropical and regional biomass models in relation to model efficiency and model prediction error.

Harmonious Development of Utilization and Protection of Tidal Flats and Wetlands-A Case Study in Shanghai Area

Spatial, environmental, and material resources are important for tidal flats and wetlands, thus, a harmonious balance between utilization and protection should be maintained. In the present study, the concept of tidal flat is defined, and its spatial limitation is also clarified. Located at the Yangtze Estuary, tidal flats in Shanghai area are selected for study. The relationship between water discharge and sediment transport of the Yangtze River, allowed exploration intensity and needs for wetland protection are discussed in the paper. The dynamic process and changing trend for different types of tidal flats are illustrated in detail. Regulations are proposed for a reasonable exploitation, dynamic protection, and ecosystem restoration of each individual tidal fiat and wetland. Some valuable suggestions are put forward for further study about the sustain＇able exploitation of offshore resources in Shanghai area.

Significance of Substrate Selection in the Efficiency of Wastewater Treatment in Constructed Wetlands (CWs)

Constructed wetlands (CWs) can achieve a high-quality wastewater treatment and a quality that meets the prescribed standard, defined by legislation on wastewater discharge. A limitation in the application of constructed wetlands (CWs) is the large area requirement, which limits their application. The subject matter of this research is to check the possibility of improving the efficiency of wastewater treatment and reducing the required area for constructed wetlands (CWs) by using an adequate substrate under the conditions found in Montenegro. In the described experiment, the constructed wetlands (CW) have a vertical flow system and play the role of a secondary wastewater treatment, receiving water from the existing WWTP in Podgorica after the primary treatment. These vertical flow systems reflect experience with the use of similar systems in Slovenija, Austria and Italy. Measurements to date show that the substrate plays an important role and that wastewater treatment efficacy varies significantly with respect to the type of substrate when used under the conditions available in Montenegro.

Study on Winter Operation Process of the Surface Flow Constructed Wetland in Tianjin Area

[Objective] The research aimed to study winter operation process of the surface flow constructed wetland in ＂rianjin area. [Method] In view of climate characteristics in Tianjin, by the way of running under the ice, winter operation experiment of the surface flow constructed wetland in Tianjin was conducted, with the expectation to get some useful process parameters to run such systems in North China in winter. [ Result] Although purification effect of the sewage by surface flow constructed wetland in winter was worse than that in other seasons （ average reduction of about 20%）, surface flow constructed wetland running under the ice was feasible in Tianjin area. When surface flow constructed wetland in North China ran under ice in winter, it was suggested that the outlet must be located in a low position to prevent to be completely frozen, and running water depth should not be less than 50 -60 cm. The hydraulic load could be raised on the basis of reflux, and hydraulic retention time should maintain less than 4 d to keep water-soil interface not freezing. Inlet water depth should be increased as much as possible to improve temperature in the system. V Conclusion1 The research could provide reference for promotion and application of the surface flow constructed wetland in North China.

城市蓄滞洪区生态水景公园概念规划及景观节点详细设计:以宋庄蓄洪生态水景公园为例

宋庄蓄滞洪区是北京城市副中心防洪格局通州堰中的重要组成部分,其防洪功能至关重要。为了使蓄滞洪区既满足汛期防洪调蓄的作用,降低洪水对周边地区的影响,保障市民的生命财产安全,又满足市民非汛期生态休闲目的,以宋庄蓄洪生态水景公园为例,结合现状条件和洪水的启示,打破原有水绿界限,提出全新的设计理念,重视前期规划设计,通过融合多种功能、塑造立体空间、打造技术亮点等方法与水系串联、土方平衡、湿地净化、绿化种植等措施相结合,构建绿色、生态、健康的开放式生态水景公园——宋庄沁园,实现宋庄蓄洪区的综合利用。以生态水景的形态与东郊森林公园、温榆河河堤自然串联为一个整体,保障副中心的防洪安全,提高蓄洪调度能力,有效降低洪水风险,提升周边生态环境,满足市民观景、休闲、健身等活动需求,充分展示水生态、水文化、水技术等科普知识,成为副中心“通州堰”生态水景观体系的点睛之笔。

鄱阳湖双退区受损湿地土壤氮素空间分布特征及影响因素

【目的】土壤氮素是湿地营养水平的重要指标,研究鄱阳湖双退区受损湿地土壤氮素空间分布特征及其影响因素,为开展鄱阳湖受损湿地植被生态恢复与重建提供科学依据。【方法】在鄱阳湖退田还湖区中的双退区选择位于江西省都昌县多宝乡的马影湖湿地4类受损湿地土壤,分别为沼泽土、草甸土、草甸沼泽土和次生草甸沼泽土,研究0~20 cm(表层土)、20~40 cm(中层土)和40~60 cm(深层土)3个土壤剖面的全氮(TN)、硝态氮(NO_(3)^(-)-N)和氨态氮(NH_(4)^(+)-N)的空间分布特征,利用聚类推进树算法量化环境因子对氮素的相对贡献,利用Pearson相关性分析氮素与环境因子的关系、利用结构方程模型分析了环境因子对氮素的影响路径。【结果】除沼泽土NH_(4)^(+)-N以中层土最高及次生草甸沼泽土土壤TN、NO_(3)^(-)-N、NH_(4)^(+)-N分别以中层土和深层土最高外,其余土壤类型皆以表层(0~20 cm)土壤氮素含量最高,分别为TN(0.35±0.03)g/kg、NH_(4)^(+)-N(4.02±0.38)mg/kg和NO_(3)^(-)-N(4.84±0.53)mg/kg。土层深度、有效磷(AP)对氮素分布和积累具有重要影响,pH通过影响土壤有机碳(SOC)、AP、有效钾(AK)间接影响到氮素,阳离子交换量(CEC)通过影响SOC间接影响到氮素。【结论】与鄱阳湖天然湿地相比,区内4类受损湿地土壤氮素含量均处于极低水平,各氮素最高值多集中在土壤表层,其中TN以草甸土含量最高也最易淋失,其次为草甸沼泽土、次生草甸沼泽土,沼泽土最少且最易被流水冲洗,氮素的积累和分布受土层深度、AP、pH、CEC等影响较大。

典型挺水植物应用于湿地生态修复工程污染净化效应差异性研究

以洱海流域北部上游东湖片区库塘湿地中水生植物为研究对象,选取5种主要水生植物,寻求净化湿地水质的最佳植物组合。结果表明:东湖片区库塘湿地水体总磷、总氮、氨氮、化学需氧量分别为0.09~0.23、0.80~3.28、0.18~0.89、12.00~37.00 mg/L,总体符合《地表水环境质量标准》(GB 3838—2002)中Ⅳ类要求;综合比较发现,植物组合群落生物量和碳氮磷累积效应优于单一植物;植物组合对水体碳氮磷具有一定的吸收净化作用。

粤港澳大湾区湿地生态系统服务及价值评估研究进展及展望

粤港澳大湾区湿地生态系统近年受气候变化与人类活动因素的双重胁迫,湿地面积急剧萎缩,湿地生态系统结构、功能、服务、生态过程等愈加复杂,加剧了湿地生态系统服务评估及保护工作的难度。因此如何在类型丰富、结构复杂的大湾区湿地生态系统构建针对性的、适用性的生态系统服务评估体系,进而开展系统性的、针对性的生态服务及资产评估,也是现阶段大湾区自然资源监测及生态安全评估的重点及重大课题之一。以粤港澳大湾区湿地生态系统为分析对象,梳理湿地生态系统服务及其价值研究进展。研究发现该区域存在湿地遥感监测能力不足、湿地生态系统服务价值评估体系不适用等关键问题,受限于粤港澳大湾区的气候特征、复杂的地表环境及湿地类型,此区域湿地生态系统服务价值评估难度将会提升。针对粤港澳大湾区湿地生态服务价值评估目前面临的挑战,展望粤港澳大湾区湿地生态系统服务价值评估的三个重要方向:1.实现湿地参数精准提取,构建高时间分辨率湿地数据集;2.针对湿地资源特征,构建大湾区湿地生态系统服务价值评估体系;3.建立湿地资源价值评价系统,实现湿地从“资源评价”到“资产核算”的发展。

铁尾矿人工湿地填料的制备及其成孔机理研究

为解决铁尾矿堆积问题,以铁尾矿和木屑粉为主要原料,制备出性能较好的铁尾矿人工湿地填料FITCWS。该填料焙烧前后的主要矿物成分由长石和角闪石转变为辉石。焙烧温度(T)、木屑粉用量(η)、木屑粉粒径(dw)和尾矿粒径(di)均可影响FITCWS的物理性能。T是影响吸水率和颗粒强度的主要因素,dw和di是影响比表面积和孔容的主要因素,dw、T和di是影响孔径的主要因素。T越高,FITCWS的颗粒强度越大,吸水率越低;dw和di越小,FITCWS表面的粗糙度越低,比表面积、孔容和孔径越大。制备FITCWS的优选方案是:η为0.3,T为1200℃,dw和di均为200~250目(58~74μm),所制FITCWS的吸水率为44%,颗粒强度为115.9 N,比表面积为6.932 m^(2)/g,孔容为0.017 cm^(3)/g,孔径为3.169 nm,孔形为通透的狭缝。

人类活动对河岸湿地植物群落的影响

人类活动干扰是河岸带外来植物侵入的主要原因之一.选取唐河县乡村段和城市段,对比研究河岸湿地外来植物群落特征,旨在探明不同类型人类活动对外来植物的影响程度.研究发现,6个处理中乡村段河岸上乡土植物的比例最高(65.38%).乡村段的乡土植物比城市段多,乡村段的入侵植物明显低于城市段.无论是乡村段还是城市段,乡土植物优势度都最高,乡村段河岸的乡土植物优势度高于城市段,而乡村段河岸外来植物的优势度明显低于城市段,乡村段河岸的入侵植物优势度也显著高于城市段.在乡村段的外来植物中,多年生旱生草本植物的比例最高(38.29%),而在城市段的外来植物中,一年生中生草本植物的比例最高(29.45%).乡村段与城市段的本土植物相似度最高(0.823),其次是乡村段与城市段的外来植物(0.692).随着人类活动干扰强度不断增加,物种的更替变化导致不同区域的植物群落构成呈现出很大的差异,降低了区域之间植物物种的相似性.唐河县段河岸带外来植物种类的构成特点,反映出人类活动对河岸带外来植物干扰逐渐扩大的趋势,包括快速城市化和农业活动等.

基于网络文本的生态旅游体验研究——以世界自然遗产地盐城黄海湿地条子泥景区为例

游客体验要素及其满意度是影响旅游目的地发展的重要因素。以世界自然遗产地黄海湿地典型景区条子泥为研究案例,借助从携程网、大众点评网、马蜂窝和穷游网收集的612条游客有效在线评价,采用社会网络分析法(SNA)和重要性-表现程度分析法(IPA)研究湿地生态旅游者的体验要素、结构及质量评价,从数据关系角度揭示湿地生态旅游体验结构及内在关联机制。SNA结果显示,湿地生态旅游者的体验结构主要包含以湿地特色活动为主的核心体验以及以生态游憩为特征的支持体验;IPA结果显示,湿地生态旅游者整体评价较高,但公共服务设施、餐饮美食等方面还有待景区管理者提升。基于此,应加强公共设施建设,拓展湿地体验区域;规划生态游憩空间,丰富餐饮美食体验;联动沿海特色村镇,促进景区互动合作。

包头黄河国家湿地公园小白河片区开发特许经营模式构建

基于包头黄河国家湿地公园小白河片区的开发利用现状分析,结合小白河片区不同功能分区的保护规划,构建特许经营模式。结果表明:由包头市林业和草原局作为所有权委托代理主体,在合理利用区开展特许经营活动;构建所有权、代理权、特许经营权“三权分置”制度,包括特许经营主体准入制度、公众参与制度和预期收益分配制度;拟定特许经营合同;再配套以相应的特许经营保障机制。小白河片区湿地资源开发利用引入特许经营市场化工具,可提高国家对湿地资源的优化配置和湿地资源资产的经营式管理,对保护国家湿地生态环境、合理开发湿地资源资产具有重要指导意义。

合肥庐江许桥联圩湿地生态修复实践

以环巢湖区域典型圩田湿地——许桥联圩为例,基于圩田湿地水文环境紊乱、生境破坏、景观特色弱化等生态问题,提出因地制宜的生态修复策略:1)在保护现有水网格局的基础上,合理设计渠、塘、水闸和泵站等,形成层级有序的水生态系统,提高湿地调蓄能力;2)保护圩田原生态,因地制宜构建沼泽、生态塘、生态岛等多样化生境,提高生物多样性;3)延续原空间特色为主,丰富植物景观风貌、完善配套设施等,打造低干扰性生态景观。湿地修复效果预期较好,可为其他类似圩田湿地生态修复提供借鉴。

十八联圩生态湿地蓄洪区保庄圩设计方案分析

保庄圩是生态湿地蓄洪区规划的重要组成部分,直接影响到蓄洪安全。以十八联圩生态湿地蓄洪区为例,在确定蓄洪区风险等级和保庄圩建设标准后通过比选确定保庄圩设计方案。十八联圩生态湿地蓄洪区保庄圩建成后在汛期能有效发挥避洪功能,非汛期则利用圩内小微湿地达到缓解污染、净化水质和丰富物种的作用。方案可为其他类似生态湿地蓄洪区保庄圩设计提供参考。

生态湿地蓄洪区水土保持方案探讨

文章以巢湖十八联圩生态湿地蓄洪区为研究对象,通过分析工程现状及主体设计内容,确定水保方案执行的水土流失防治标准,制定防治措施总体布局,全面界定主设中水保措施,并在方案中进行补充设计,同时对防治效果进行预测,使项目区水土流失得到有效治理,生态环境得到改善,以期为同类项目的水保方案设计带来一些参考。

面向意象视角的湿地景观设计研究

意象视角的设计注重通过艺术表达和审美感受来打造景观,使湿地景区更加美丽、独特和具有艺术感。研究以面向意象视角的湿地景观设计为研究对象,探讨了如何将面向意象的湿地景观设计策略与湿地景观的特征与表征相结合,探究了湿地景观的设计方法。研究以天生桥景区为案例,首先,通过对天生桥景区周围湿地生态系统的分析,强调保护湿地特征和生态系统的完整性的重要性;其次,结合玻璃站台的设计,详细阐述了如何通过透明材料和合理的布局,实现游客对景区全景的观赏,同时保护湿地的自然特征;再次,以空中步道设计为例,展示了如何将步道融入景观中,提供与湿地互动的体验,让游客更贴近自然。此外,通过小吃摊的设计,强调了湿地景观与人文意象之间的关系。