Historical Changes of Hydrological Connectivity of Selected Polish Floodplain Lakes

The main ecological and hydrological features of floodplain lakes (FPL) depend on the flood pulse. Temporal variations of connectivity result from natural fluctuations in a parent river water levels. The study area was a fragment of left fraction of the Bug River valley, within a gorge‐like section between Dorohusk and W?odawa. The aim of the study was to define a duration and frequency of potamophases and limnophases of 20 FPLs, during the period 1952–2013. A large variation of limnophase frequency was observed. The most frequently occurs short (8–30 days) and medium‐length (183–365 days) limnophases. In case of potamophases the most frequent were short episodes (8–30 days). In most water bodies, a general similarity of the duration of functional periods was observed. The average ratio of the duration of both phases showed prevalence of limnophases. Generally, two factors were observed that shape variability of functional periods in the study area: quantity of water input and FPL morphometry. The lower lake volume and less stable water input, the higher variability of hydrological connectivity. Copyright © 2016 John Wiley & Sons, Ltd.     

黄河下游滩区受淹后国家补偿问题研究

通过对黄河下游滩区基本情况和功能的分析以及与淮河行洪区的比较，指出黄河下游滩区频繁受淹对黄河治理开发的不利影响主要有：①中小洪水时影响防洪安全；②影响滩区人民生命财产安全和区域经济的发展；③限制了黄河治理方略的实施；④影响了河道依法管理的进程。黄河下游滩区具有明显的蓄滞洪区的性质和功能，几十年来，这些功能的发挥为黄河的安澜起到了巨大的作用，但由于黄河处理泥沙的特殊需要，滩区没有按蓄滞洪区进行控制运用，造成了黄河下游滩区没有能够享有蓄滞洪区的补偿政策。因而，应尽快将黄河下游滩区列入国家蓄滞洪区名录，受淹后由国家给予相应补偿，国家补偿的基本方式包括：①风险公平的事前基本补偿；②临时撤离的安置补偿；③基本生产损失的补偿等。     

ESTIMATION OF JUVENILE SALMON HABITAT IN PACIFIC RIM RIVERS USING MULTISCALAR REMOTE SENSING AND GEOSPATIAL ANALYSIS

We conducted a regional classification and analysis of riverine floodplain physical features that represent key attributes of salmon rearing habitats. Riverine habitat classifications, including floodplain area and river channel complexity, were derived at moderate (30 m) spatial resolution using multispectral Landsat imagery and global terrain data (90 m) encompassing over 3 400 000 km² and most North Pacific Rim (NPR) salmon rivers. Similar classifications were derived using finer scale (i.e. ≤ 2.4‐m resolution) remote sensing data over a smaller set of 31 regionally representative flood plains. A suite of physical habitat metrics (e.g. channel sinuosity, nodes, floodplain width) were derived from each dataset and used to assess the congruence between similar habitat features at the different spatial scales and to evaluate the utility of moderate scale geospatial data for determining abundance of selected juvenile salmon habitats relative to fine scale remote sensing measurements. The resulting habitat metrics corresponded favorably (p < 0.0001) between the moderate scale and the fine scale floodplain classifications; a subset of these metrics (channel nodes and maximum floodplain width) also were strong indicators (R² > 0.5, p < 0.0001) of floodplain habitats defined from the finer scale analysis. These relationships were used to estimate the abundance and distribution of three critical shallow water floodplain habitats for juvenile salmon (parafluvial and orthofluvial springs, and shallow shore) across the entire NPR domain. The resulting database provides a potential tool to evaluate and prioritize salmon conservation efforts both within individual river systems and across major catchments on the basis of physical habitat distribution and abundance. Copyright © 2011 John Wiley & Sons, Ltd.     

Effect of Spatial Heterogeneity on Zooplankton Diversity: A Multi‐Scale Habitat Approximation in a Floodplain Lake

Environmental heterogeneity is an essential quality of ecosystems as it has important implications in community structure. Macrophytes are a main component of environmental heterogeneity in floodplain lakes, and their dynamics are highly influenced by water level changes. In this context, we analysed at different spatial scales the relationship among hydrological variations, environmental heterogeneity associated to macrophytes and zooplankton regional diversity (γ diversity) in a South American floodplain lake adjacent to the Paraná River, and we also compared the local zooplankton diversity (α diversity) among the different environments that comprised the lake heterogeneity. At very low waters, the environmental heterogeneity was reduced as the lake was mainly limited to open water areas with low zooplankton diversity. At high waters, the profuse vegetation development (emergent and free‐floating), in mixed or homogeneous patches, determined a higher lake environmental heterogeneity with enhanced regional zooplankton diversity; littoral species increased over limnetic ones. Zooplankton α diversity was higher in environments with free‐floating macrophytes than in those without these plants. The structural complexity in the water column provided by plant roots would be closely related to the enhanced diversity found under free‐floating mats. This study contributes to the knowledge on the effects of strong water level variations on environmental heterogeneity, which is strongly associated to macrophytes and on zooplankton diversity, and highlights the role of free‐floating plants as diversity hosts and ‘key structures’ in floodplain lakes. Copyright © 2013 John Wiley & Sons, Ltd.     

基于Landsat2T M 影像的洞庭湖水面动态变化

为了探究近20 年来洞庭湖萎缩状况, 定量评价其水面面积变化情况, 选择Landsat TM 遥感影像作为数据 源, 采用单波段阈值分析法、多波段谱间关系法、水体指数法、植被指数法和目视解译法对洞庭湖水体进行了解译, 探讨了1993 年- 2010 年洞庭湖水体面积动态变化状况。结果表明, 若以1949 年洞庭湖面积( km2 ) 作为历史参考 水面, 则18 年间湖面积萎缩严重, 秋季平水期萎缩比例均超40%; 若以1978 年洞庭湖水面为参考, 则萎缩比例少 于40%。研究还表明, TM 图像的72422 波段组合对于洞庭湖水体的解译非常有效, 可以作为地区水文水资源研究 的重要手段。     

Multitemporal Monitoring of Land Degradation Risk Due to Soil Loss in a Fire-Prone Mediterranean Landscape Using Multi-decadal Landsat Imagery

Water Resources Management - Natural, as well as human-induced, landscape changes may have profound effects on soil-loss rates in Mediterranean countries. Knowledge of the spatial and temporal...     

频率分析法在水文预报方案中的应用

水文预报方案是洪水预报工作中不可缺少的理论技术工具,工作中发现用实测的水文数据编制的方案往往不能预报超历史洪水、特大洪水和稀遇洪水。在这里采用频率分析的方法延长方案相关曲线,达到能够预报超历史洪水、特大洪水和稀遇洪水的目的。     

The glaciers of the Hindu Kush Himalayas: current status and observed changes from the 1980s to 2010

The fate of the Hindu Kush Himalayan glaciers has been a topic of heated debate due to their rapid melting and retreat. The underlying reason for the debate is the lack of systematic large-scale observations of the extent of glaciers in the region owing to the high altitude, remoteness of the terrain, and extreme climatic conditions. Here we present a remote sensing–based comprehensive assessment of the current status and observed changes in the glacier extent of the Hindu Kush Himalayas. It reveals highly heterogeneous, yet undeniable impacts of climate change.     

RUSLE2 Model Application for Soil Erosion Assessment Using Remote Sensing and GIS

The study is focused on the estimation of rate of soil erosion, using Revised Universal Soil Loss Eq. 2 (RUSLE2), in the Veppanapalli subwatershed of Krishnagiri catchment located in Tamil Nadu, India. The soil erosion is estimated for each of the hillslope units in the study area. The factors considered are intensity of rainfall, type of soil, land use classification and the existing soil conservation practices. Detailed analysis of soil samples were done to assess the texture, structure, permeability and organic matter content of the soil samples of each hillslope unit. The required data for the other parameters were estimated by carrying out intense field investigations and by the analysis of the satellite imagery of 5.6 m resolution. A data base was created with all the subfactor values for the hillslope units. Incorporation of remote sensing technique and Geographic Information System (GIS) made the spatial analysis of the study more reliable and accurate. The annual average soil erosion rate is estimated as 25 t/ha/year, which is on a higher range. This indicates the immediate need for the adoption of proper conservation strategies in this area to control the eutrophication in the Krishnagiri reservoir and to prevent further watershed degradation.     

近30年来浏阳河流域景观格局动态及稳定性时空变化特征

为揭示浏阳河流域的景观稳定性时空变化特征,在RS和GIS技术支持下,利用1985年、2000年和2015年遥感影像获取流域内3期土地利用/覆盖类型数据,运用景观分析方法定量分析了1985—2015年间浏阳河流域景观结构变异特征、稳定性变化特征及景观稳定性与景观类型的相关关系.结果表明:①在1985—2015年间,浏阳河...     

Integrating remotely acquired and field data to assess effects of setback levees on riparian and aquatic habitats in glacial‐melt water rivers

Setback levees, in which levees are reconstructed at a greater distance from a river channel, are a promising restoration technique particularly for alluvial rivers with broad floodplains where river‐floodplain connectivity is essential to ecological processes. Documenting the ecological outcomes of restoration activities is essential for assessing the comparative benefits of different restoration approaches and for justifying new restoration projects. Remote sensing of aquatic habitats offers one approach for comprehensive, objective documentation of river and floodplain habitats, but is difficult in glacial rivers because of high suspended‐sediment concentrations, braiding and a lack of large, well‐differentiated channel forms such as riffles and pools. Remote imagery and field surveys were used to assess the effects of recent and planned setback levees along the Puyallup River and, more generally, the application of multispectral imagery for classifying aquatic and riparian habitats in glacial‐melt water rivers. Airborne images were acquired with a horizontal ground resolution of 0.5 m in three spectral bands (0.545–0.555, 0.665–0.675 and 0.790–0.810 µm) spanning from green to near infrared (NIR) wavelengths. Field surveys identified river and floodplain habitat features and provided the basis for a comparative hydraulic analysis. Broad categories of aquatic habitat (smooth and rough water surface), exposed sediment (sand and boulder) and vegetated surfaces (herbaceous and deciduous shrub/forest) were classified accurately using the airborne images. Other categories [e.g. conifers, boulder, large woody debris (LWD)] and subdivisions of broad categories (e.g. riffles and runs) were not successfully classified either because these features did not form large patches that could be identified on the imagery or their spectral reflectances were not distinct from those of other habitat types. Airborne imagery was critical for assessing fine‐scale aquatic habitat heterogeneity including shallow, low‐velocity regions that were not feasible or practical to map in the field in many cases due to their widespread distribution, small size and poorly defined boundaries with other habitat types. At the reach‐scale, the setback levee affected the amount and distribution of riparian and aquatic habitats: (1) the area of all habitats was greater where levees had been set back and with relatively more vegetated floodplain habitat and relatively less exposed sediment and aquatic habitat, (2) where levees confine the river, less low‐velocity aquatic habitat is present over a range of flows with a higher degree of bed instability during high flows. As river restoration proceeds in the Pacific Northwest and elsewhere, remotely acquired imagery will be important for documenting its effects on the amount and distribution of aquatic and floodplain habitats, complimenting field data as a quantitative basis for evaluating project efficacy. Copyright © 2008 John Wiley & Sons, Ltd.     

鄱阳湖淹没范围、水深和库容的遥感研究

鄱阳湖湿地是国际重要湿地,也是长江的主要蓄洪区,研究鄱阳湖淹没范围、淹没水深和库容对长江流域水文和湿地保护都有重要意义。通过对13个时相的Landsat卫星遥感影像进行非监督分类提取湖泊水体淹没范围,叠加鄱阳湖区地形图,获取水体边界的水位,通过空间内插计算鄱阳湖水位空间分布,进一步计算水深空间分布和库容量,在此基础上,根据鄱阳湖都昌水文站观测水位,计算鄱阳湖水位-面积曲线和水位-库容曲线。结果表明:鄱阳湖水位存在高水位时空间一致性,低水位时水位存在较大的空间差异,湖泊水位差可达到5 m;水位-淹没面积曲线和水位-库容曲线分别可以由对数方程和二次曲线方程拟合。     

Using airborne scanning laser altimetry (LiDAR) to estimate surface connectivity of floodplain water bodies

This study tested the applicability of airborne scanning laser altimetry (LiDAR) for characterizing surface connectivity of floodplain water bodies by comparing it with in situ measurements of water levels, and examined whether LiDAR derived data accurately predicted the occurrence of globally imperilled unionid mussels. We intensively examined 10 isolated and 3 connected floodplain water bodies (IWBs and CWBs, respectively) located within a 15‐km lowland segment of the Kiso River in Japan. Using a digital elevation model (DEM) of floodplain ground surface, which is derived from LiDAR, and water surface DEM, which is obtained from records of water level fluctuations, the frequency of surface connectivity between IWBs and the main channel (inundation frequency) was calculated. Inundation frequency of IWBs was also measured in situ using water level and temperature probes. Also, the occurrence of mussels in CWBs and IWBs were examined. LiDAR derived data well predicted in situ derived one with a high level of accuracy (r² > 0.77), validating the LiDAR‐based approach. Some errors existed in the predictive model, indicating that the applicability of LiDAR data is limited by its spatial resolution and snapshot nature. The occurrence of mussels was positively explained by an increasing level of inundation frequency, and the high accuracies of empirical models were validated using data for other 67 water bodies within the study segment. This study overall demonstrated a high potential of LiDAR data for efficiently monitoring hydrological and biological conditions of floodplain water bodies in the Kiso River and beyond. Copyright © 2010 John Wiley & Sons, Ltd.     

Delineation of Flood-Prone Areas Using Remote Sensing Techniques

Flood problems resulting due to heavy rainfall and drainage congestion are being regularly experienced in plain areas of Bihar, India. Due to this problem, power plant located in Koa catchment, Kahalgaon, Bihar, is faces huge loss at the time of flood. In this paper, the flood-affected areas in Koa catchment have been mapped using remote sensing satellite data (IRS LISS III, 1999 and Landsat TM, 1995). A range of image processing techniques has been used, including simple density slicing, Tasseled Cap Transformation and water-specific index. The results obtained using different approaches have been analysed. Result indicates that a Normalized Difference Water Index (NDWI) based approach produced best results.     

基于遥感和GIS的流域社会经济数据空间化方法研究

人口和社会经济数据及其空间分布,在资源、环境及自然灾害评估中的重要性已被广泛认知。把遥感和GIS技术相结合,是探讨解决社会经济统计数据空间化的重要思路。以东江流域为例,以多期人口、GDP、土地利用数据为基础,建立东江流域人口与土地利用、GDP和土地利用的多元线性回归模型;以土地利用数据和100 m×100 m网格数据为基础,构建东江流域人口和GDP空间分布约束力指标图层;然后结合统计模型和面积内插,实现了东江流域2009年人口、GDP统计数据的空间化。在县域空间尺度上对模拟结果进行了验证,与同尺度研究工作进行了对比,结果显示模拟得到的人口和GDP空间分布数据,与同尺度的研究工作处于同一精度或者略高的精度水平,表明该方法是一种进行流域社会经济数据空间化处理的有效方法。     

基于降雨频率的泥石流危险性评价研究

以强震区四川省汶川县为典型研究区,采用GIS技术与层次-信息量模型相结合的方法,针对震区震后特殊的地质环境,首先,选取了6类影响物源敏感性的因子(坡度、高程、距水系距离带、断层影响带、地震烈度、岩土体类型),对形成泥石流的最重要影响因素物源进行敏感性分析,生成汶川县滑坡敏感性评价图,将其归化至泥石流流域中,计算出泥石流敏感性,并分别在100 a一遇和50 a一遇2种不同降雨频率的影响下分析其泥石流危险性。最终,利用ArcGIS空间分析功能生成高、中、低3级危险性区划图,从而确定在不同降雨下需要重点监测与防治的泥石流沟道。     

VMS景观质量评价在石膏山水库工程环评中的应用

石膏山水库的库区、坝址、上坝及改线公路、管理处等位于国家森林公园石膏山风景区内,该水库的兴建,将改变原来水体的形态与特征,加上新修的人工建筑物,对周围的景观会有影响。文中针对石膏山水库工程,采用美国林务局风景管理系统（VMS）对景观质量影响进行了评价。     

Estimation of Soil Erosion for a Himalayan Watershed Using GIS Technique

The fragile ecosystem of the Himalayas has been an increasing cause of concern to environmentalists and water resources planners. The steep slopes in the Himalayas along with depletedforest cover, as well as high seismicity have been major factors in soil erosion and sedimentation in river reaches. Prediction ofsoil erosion is a necessity if adequate provision is to be madein the design of conservation structures to offset the ill effects of sedimentation during their lifetime.In the present study, two different soil erosion models, i.e. theMorgan model and Universal Soil Loss Equation (USLE) model, have been used to estimate soil erosion from a Himalayan watershed.Parameters required for both models were generated using remotesensing and ancillary data in GIS mode. The soil erosion estimated by Morgan model is in the order of 2200 t km^-2 yr^-1 and is within the limits reported for this region.The soil erosion estimated by USLE gives a higher rate. Therefore, for the present study the Morgan model gives, for area located in hilly terrain, fairly good results.     

Hyperspatial Remote Sensing of Channel Reach Morphology and Hydraulic Fish Habitat Using an Unmanned Aerial Vehicle (UAV): A First Assessment in the Context of River Research and Management

In this paper, we assess the capabilities of an unmanned/uninhabited aerial vehicle (UAV) to characterize the channel morphology and hydraulic habitat of a 1‐km reach of the Elbow River, Alberta, Canada, with the goal of identifying the advantages and challenges of this technology for river research and management. Using a small quadcopter UAV to acquire overlapping images and softcopy photogrammetry, we constructed a 5‐cm resolution orthomosaic image and digital elevation model (DEM). The orthomosaic was used to map the distribution of geomorphic and aquatic habitat features, including bathymetry, grain sizes, undercut banks, forested channel margins, and large wood. The DEM was used to initialize and run River2D, a two‐dimensional hydrodynamic model, and resulting depth and velocity distributions were combined with the mapped physical habitat features to produce refined estimates of available habitat in terms of weighted usable area. Based on 297 checkpoints, the vertical root‐mean‐squared error of the DEM was 8.8 cm in exposed areas and 11.9 cm in submerged areas following correction of the DEM for overprediction of elevations as a result of the refractive effects of water. Overall, we find several advantages of UAV‐based imagery including low cost, high efficiency, operational flexibility, high vertical accuracy, and centimetre‐scale resolution. We also identify some challenges, including vegetation obstructions of the ground surface, turbidity, which can limit bathymetry extraction, and an immature regulatory landscape, which may slow the adoption of this technology for operational measurements. However, by enabling dynamic linkages between geomorphic processes and aquatic habitat to be established, we believe that the advantages of UAVs make them ideally suited to river research and management. Copyright © 2014 John Wiley & Sons, Ltd.     

基于Landsat遥感影像解译的神农架林区 近30年土地覆盖动态变化

利用神农架林区1987年、2000年、2013年Landsat卫星遥感影像,结合地面调查信息,运用ERDAS软件分别解译出这3个时期地表覆盖类型,同时对比3个时期地表覆盖类型的变化,统计分析出3个时期神农架林区森林变化面积和来源。结果显示1987—2000年森林面积增长缓慢,净增长了14.70 km²,变化主要来自灌丛和草地的转化;2000—2013年期间森林面积增长迅速,净增长了207.49 km²,变化主要来自灌丛、草地和农田的转化。运用遥感技术连续、宏观、动态地监测神农架林区地表覆盖变化,不仅丰富了神农架林区的本底资料,同时也为生态环境监测与生物多样性保护提供了重要的数据。