基于Sentinel-2与随机森林算法的太湖水生植被分布监测

基于2018—2021年太湖地区哨兵2号（Sentinel-2）卫星遥感影像和随机森林算法，结合植被敏感指数，开展太湖水生植被分布监测，综合分析了水生植被的时空变化特征，初步揭示了太湖水生植被的动态变化。结果表明，太湖水生植被分布面积有逐年上升的趋势，且年间变化具有明显的单峰型特征，表现为春季沉寂，夏季快速增长，秋季达到暴发期，冬季面积开始减退；太湖水生植被主要分布于东太湖、东部沿岸和贡湖，类型以沉水植被为主，其中浮叶植被主要分布于东太湖，挺水植被主要分布于东太湖沿岸的浅水区域；沉水植被主要分布于东部沿岸和贡湖；水生植被主要分布的东太湖水域，其水质总体优于太湖其他水域。     

湖库水生植被光学遥感监测研究进展和展望

水生植被在湖库生态系统中发挥稳定沉积物、净化水质、平衡水生生态系统等作用,监测水生植被变化对湖库生态环境的监测具有重要意义。梳理了国内外利用高光谱、多光谱光学卫星遥感数据提取湖库水生植被的方法,尤其是针对其中涉及的阈值确定问题进行总结分析,介绍了典型研究区水生植被时空分布和变化以及与水质的关系,最后给出一些水生植被遥感监测的展望。     

基于多星遥感影像的太湖北部湖湾春季沉水植被分布动态监测

利用多星遥感影像动态监测了2015年春季太湖北部湖湾沉水植被分布的变化过程,并对水生植被遥感监测中的几个关键问题展开了探讨。决策树方法获取的水生植被分布结果表明,2015年4月28日太湖北部湖湾发现明显沉水植被分布面积约11.2 km~2,与2014年同期相比,新出现的较大面积沉水植被分布区域主要集中在田鸡山西和锡东水厂附近。提出应及时清理打捞,避免水生植被死亡腐烂,威胁水质安全。     

基于NDVI指数的骆马湖水生植被分级研究

基于典型时段骆马湖LandsatTM遥感影像,利用归一化植被指数（NDVI）法对骆马湖水生植被进行分级研究.采用标准差分级方法,将骆马湖水生植被分为5个等级.研究结果表明,利用这种分级方法处理的图像能够较准确地反映骆马湖水生植被区域分布和等级分区,能够更准确地给出采砂区和生态保护区域的位置,增强湖区水生态环境保护工作的有效性和针对性.     

太湖流域生态安全监测体系的构建

针对太湖流域水质污染、湖体富营养化、饮用水质受影响和水生植被减少等生态问题，提出了构建生态安全监测指标体系、布设四类监测点位、引入科学的监测技术与评价体系，从而构建流域生态安全监测体系的设想。     

水生生物监测质量控制方法探讨

水生生物监测质量控制方法探讨陈家厚，杨瑞莅（黑龙江省环境监测中心站，哈尔滨１５００５６）水生生物监测，在我国已作为例行监测项目纳入到环境监测体系，随着《规范》的贯彻实施，水生生物监测技术有了较大的进展，但是目前尚无科学完善的质量控制方法，影响和束缚了...     

常州地区植被排放VOC的估算研究

通过对2011年常州地区各类植物VOC排放因子，以及各类植被分布面积等数据统计分析，采用BEIS模型为参考的估算方法，建立起常州地区植被VOC的排放清单。结果表明，植被所排放VOC的变化规律既与植物本身有关又与气温和太阳辐射有关，区域内年植被VOC的总排放量为1．13×104 t。     

固城湖水环境现状调查与评价

对固城湖水环境现状进行了调查与评价。结果表明．除湖心区断面枯水期总磷达Ⅳ类标准外，其余断面平、丰、枯水期水质均达Ⅲ类水标准。固城湖水体呈中营养化状态．且综合营养状态指数已接近富营养状态。指出，面源污染，内源污染。养殖污染。流域内的航运污染是造成固城湖水体富营养化的主要原素。提出，应严格控制各类污染源，建立流域内的污水处理厂．保护森林植被．推广使用无磷洗涤剂、生态化肥、生态农药；定期疏浚湖底淤泥，改良现有水生植被结构；加大对固城湖环境、功能和开发利用的研究及湖泊富营养化的研究．对水体中的磷、氮的化学行为及平衡进行分析，预测发展趋势。制定营养物质种类，防止其湖水向藻型湖泊发展。     

典型水生生物中微塑料的累积、清除及食物链传递效应

以环境中双壳类、鱼类及节肢类等水生生物为对象，介绍了其对微塑料的累积与清除，重点分析了微塑料特性、生物特性和食物等因素对微塑料生物累积与清除的影响，并进一步概述了微塑料沿水生食物链的传递效应，阐述了其对复合污染物食物链传递的影响过程。结果发现，微塑料在水生生物中的累积、清除与其自身尺寸、形态和聚合物类型等密切相关，水生生物的结构特异性是干扰微塑料从生物体内排泄的重要因素，有无食物的环境条件是调节双壳类和节肢类生物对微塑料累积与清除的重要路径；微塑料虽然可以通过食物链由低营养级向高营养级传递，但不一定会产生生物放大效应；微塑料的载体效应导致其复合污染物的食物链传递过程发生改变，共存污染物在生物体内的释放和吸收时间是调控微塑料复合污染物食物链传递能力的重要因素。     

CVOR在山区河道整治植被恢复综合评价中的应用研究

以石葵河生态河道治理为例，将工程扰动区划分为河道工程区（Q1）、临时施工道路区（Q2）、弃渣场区（Q3）、取土区（Q4）、临时表土堆场区（Q5）等5个分区。采用层次分析法和CVOR模型，构建山区河道整治工程扰动区植被恢复综合评价模型。结果表明：Q1区植被恢复潜力最强，生态健康等级为健康，属容易恢复区，Q4区、Q5区、Q2区生态健康等级为不健康，植被恢复潜力较弱，生态修复中须加大投资；植被恢复潜力与生态系统健康评价结果基本保持一致，基况条件对植被恢复潜力影响较大，可通过人工干扰提高扰动区植被恢复潜力，提升植被恢复效果。     

Remote sensing of aquatic vegetation: theory and applications

Aquatic vegetation is an important component of wetland and coastal ecosystems, playing a key role in the ecological functions of these environments. Surveys of macrophyte communities are commonly hindered by logistic problems, and remote sensing represents a powerful alternative, allowing comprehensive assessment and monitoring. Also, many vegetation characteristics can be estimated from reflectance measurements, such as species composition, vegetation structure, biomass, and plant physiological parameters. However, proper use of these methods requires an understanding of the physical processes behind the interaction between electromagnetic radiation and vegetation, and remote sensing of aquatic plants have some particular difficulties that have to be properly addressed in order to obtain successful results. The present paper reviews the theoretical background and possible applications of remote sensing techniques to the study of aquatic vegetation.     

The effect of river damming on vegetation: is it always unfavourable? A case study from the River Tiber (Italy)

River damming leads to strong hydromorphological alterations of the watercourse, consequently affecting river vegetation pattern. A multitemporal and spatial analysis of the dam effect on composition, structure and dynamic of the upstream vegetation was performed on Tiber River at Nazzano-dam (Rome). The main research questions were as follows: How does plant landscape vary over time and along the river? Where does the dam effect on vegetation end? How does naturalistic importance of the vegetation affected by damming change over time? Data collection was performed mapping the vegetation in aerial photos related to the period before (1944), during (1954) and after dam construction (1984, 2000). The plant landscape has significantly changed over time and along the river, particularly as a result of the dam construction (1953). The major vegetation changes have involved riparian forests and macrophytes. Dam effect on vegetation is evident up to 3 km, and gradually decreases along an attenuation zone for about another 3 km. Despite the fact that the damming has caused strong local hydromorphological modification of the river ecosystem transforming it into a sub-lacustrine habitat, it has also led to the formation of wetlands of considerable naturalistic importance. Indeed, in these man-made wetlands, optimal hydrological conditions have been created by favouring both the expansion of pre-existing riparian communities and the rooting of new aquatic communities, albeit typical of lacustrine ecosystems. Some of these plant communities have become an important food resource, refuge or nesting habitats for aquatic fauna, while others fall into category of Natura 2000 habitats. Therefore, river damming seems to have indirectly had a “favourable” effect for habitat conservation and local biodiversity.     

Behavior of di(2-ethylhexyl) phthalate discharged from domestic waste water into aquatic environment

The behavior of di(2-ethylhexyl) phthalate (DEHP) discharged from domestic waste water into river water, sediment and submerged aquatic vegetation was investigated. The concentrations of DEHP were found to be between 8-25 microg L(-1) in river water, 1,000-2,000 microg kg(-1) in sediment and less than 20-2,000 microg kg(-1) in submerged aquatic vegetation. The experiments performed in laboratory were on the biodegradation of DEHP in water and sediment, and also adsorption equilibrium of DEHP between water and sediment. The results obtained from the investigations made it clear that the high enrichment of DEHP from water to sediment was caused from not only its high adsorptive potential but also slow degradation in sediment.     

Montane meadows in the Sierra Nevada: comparing terrestrial and aquatic assessment methods

We surveyed montane meadows in the northern Sierra Nevada and southern Cascades for two field seasons to compare commonly used aquatic and terrestrial-based assessments of meadow condition. We surveyed (1) fish, (2) reptiles, (3) amphibians, (4) aquatic macroinvertebrates, (5) stream geomorphology, (6) physical habitat, and (7) terrestrial vegetation in 79 meadows between the elevations of 1,000 and 3,000?m. From the results of those surveys, we calculated five multi-metric indices based on methods commonly used by researchers and land management agencies. The five indices consisted of (1) fish only, (2) native fish and amphibians, (3) macroinvertebrates, (4) physical habitat, and (5) vegetation. We compared the results of the five indices and found that there were significant differences in the outcomes of the five indices. We found positive correlations between the vegetation index and the physical habitat index, the invertebrate index and the physical habitat index, and the two fish-based indices, but there were significant differences between indices in both range and means. We concluded that the five indices provided very different interpretations of the condition in a given meadow. While our assessment of meadow condition changed based on which index was used, each provided an assessment of different components important to the overall condition of a meadow system. Utilizing a multimetric approach that accounts for both terrestrial and aquatic habitats provides the best means to accurately assess meadow condition, particularly given the disproportionate importance of these systems in the Sierra Nevada landscape.     

新疆艾比湖流域平原区景观植被属性特征研究

在对新疆艾比湖流域平原区进行景观生态分类的基础上，利用“3S”技术叠置研究区草地资源类型图与景观类型图，对研究区景观植被属性特征进行分析。结果表明，研究区主要为荒漠、草原和草甸，共有33个植物群落类型，小蓬荒漠、梭梭荒漠、刚毛柽柳荒漠等各类荒漠面积合计约占研究区总面积的74．10％，芦苇草甸、含胡杨的芦苇草甸及矮嵩草草甸等各类草甸及草原面积也较大，占研究区总面积的18．34％。     

Macrobenthic Monitoring in the Lower St. Johns River, Florida

The macrobenthos in the oligohaline 132 km reach of the Lower St. Johns River, Florida, is an unusual blend of freshwater and marine organisms within the annelid, mollusk, aquatic insect, and crustacean groups. During 1993–1994, the community composition was freshwater-oriented in the 47 km (seg I) and estuarine-dominated in the lower 85 km (seg II). Of the total 146 taxa collected, 89% were euryecious 'eutrophic' and 'pollution-tolerant' organisms. Densities ranged between 5000 and 20 000 individuals/m² ann av and maximum densities (85 000 individuals/m²) occurred in the muck substrate at the confluence of major tributaries and embayments. Throughout the lake-like seg II, benthic hypoxia existed during much of summer through fall. Biotic index values for grab, artificial substrate, and sled trawl samples reflected greatest stresses to the macrobenthos then. Both low taxonomic diversity and densities of organisms at the most downriver stations nearest the port of Jacksonville indicated that toxic substances also adversely affected the macrobenthos. Maintenance of the narrow band of littoral submerged aquatic vegetation (SAV) and adjacent shoreline riparian vegetation is important to sustain macrobenthic communities and other kinds of aquatic life in the river.