武汉市巡司河流域水环境综合治理评估

在流域治理的大背景下,从基础特征、治理工作、治理效果、设施能力和管理水平5个方面制定16个评估指标来分析武汉市巡司河流域治理实践。通过总结治理成效,结合现存问题提出了相应的建议,为巡司河流域后续水环境治理与保护工作提供依据性、计划性、方向性、整体性的支撑。

评估流域管理措施的综合效益—水文模型系统

综合效益-水文模型系统包括农场经济模型、农场主采用行为模型、流域建模模型和评估流域效益管理措施的非市场价值经济模型。用来监测农场成本投入、污染物减少量、水质改善状况以及评估农业保护项目的社会价值。该模型系统不仅增加了经济与物理模型,而且在阐述复杂的环境保护问题时,还融入了标准和行为方面的因子。为政策制定者和项目管理者提供了一个新的模型,从而可更加经济地实现生态环境保护的目标。

CVM在流域生态价值评估中的有效性和可靠性检验——以湘江流域为例的实证分析

加强CVM有效性和可靠性检验对于CVM在流域生态价值评估中的应用具有重要意义。以湘江流域为例,对CVM在流域生态价值评估中的有效性和可靠性检验进行实证分析和探讨。研究结果显示,湘江流域上下游地区居民对湘江流域生态系统服务的WTP和WTA具有有效性。对湘江流域同一目标人群中的两个不同样本组前后两次WTP计算结果基本相符,研究结论具有可靠性。研究结果可以为流域生态价值评估、流域生态补偿标准的制定和流域生态环境治理决策和政策提供依据和参考。

白银市东大沟流域突发水环境风险评估与管理

通过对白银市东大沟流域风险源、风险受体及防控措施调查,建立了以环境风险源强度指数(S)、环境风险受体脆弱性指数(V)、环境风险防控与应急管理能力指数(M)为基础的东大沟流域突发水环境风险评估系统,对流域突发水环境风险进行量化表征,并对流域防控体系的完善提出了对策及建议。

甘肃省内陆河流域环境风险评估方法探究

流域风险评估作为环境风险评估的重要组成部分,是水环境风险管理的基础。作为甘肃省境内3大流域之一的内陆河流域,临河企业环境风险防控措施不健全、部分城市管网建设不到位以及跨河桥梁和临河道路分布环境风险较为突出。以2018年为基准年,在调查并识别甘肃省内陆河流域环境风险源及风险受体等分布特征的基础上,综合考虑流域环境风险源(主要包括工业企业危险化学品及危险废物运输情况、主要运输道路与水系交叉点、历年突发水环境事件情况)、环境风险受体(主要包括重点水系、水库、饮用水水源地保护区和下游的居民点等)以及环境风险防控与应急能力(固定源的应急物资储备情况和应急人员数量,公共应急救援能力、闸坝、导流槽及应急池等防控措施,输油(气)管线穿越情况)等要素,构建了涵盖32个指标的流域突发环境事件风险评估指标体系,通过专家打分确定指标权重,并进行量化处理;以1 km×1 km的网格为基本单元对流域风险进行评估,评估结果与提取的子流域进行叠加,识别流域水污染高风险的热点段。同时,以石羊河流域为例进行评估应用,结果表明:1)石羊河流域整体处于低风险水平;2)准确定位了石羊河流域河道500 m缓冲区内的16个风险段和具体风险情景。研究结果可为政府相关部门制定流域环境风险评估方法及水污染环境风险管控提供重要的支撑。

一种森林流域生态系统管理与评价的新技术——NetMap简介

我国目前的生态系统评估多是将森林和流域生态系统分别评估,没能真正体现生态系统各个过程与功能的耦合性及复杂性。美国加利福尼亚地理信息研究所研发的NetMap,是目前为止发展最完整的森林流域生态系统管理与评价系统,除了美国本土已有多个国家用于流域管理与评价。它以地形数据为基础,从流域角度出发,通过流域地形地貌、植被覆盖及土地利用变化、林火风险与火烈度等级、水文过程以及侵蚀潜在性等方面综合评价研究森林流域水文过程变化与生态系统健康状况,增加生态系统评估的时空性和动态过程。本文主要介绍它的背景、主要功能和应用前景。

Investigation and Risk Assessment of Alien Invasive Plants in Riparian Zone of Dongjiang River

[Objective] The aim was to conduct investigation and risk assessment of the alien invasive plants in riparian zone of Dongjiang River.[Method] The field survey was carried out by the combination methods of sampling plots investigation and route survey,and the whole Dongjiang River was covered.52 sampling points were set in the main streams,and 87 sampling points in tributaries streams,624 quadrats were set in total;multi-index comprehensive evaluation method was adopted for the risk assessment with 6 first-level indexes and 25 second-level indexes.[Result] Through the investigation on the riparian zone of Dongjiang River for 2 years,51 species of alien invasive plants were found,belonging to 17 families and 38 genera.The risk level assessment results of these 51 species showed that 18 species,such as Ageratum conyzoides,belonged to high-level risk with over 60 points;26 species,such as Chenopodium ambrosioides,were between 30 and 60 points which belonged to middle-level risk;7 species,such as Paspalum dilatatum,with less than 30 points belonged to low-level risk.[Conclusion] Basic data on the protection,water environmental management and functional zoning of riparian zone of Dongjiang River were provided.

Vulnerability of Water Resources and Its Spatial Heterogeneity in Haihe River Basin, China

To manage water resources effectively, a multiscale assessment of the vulnerability of water resources on the basis of political boundaries and watersheds is necessary. This study addressed issues on the vulnerability of water resources and provided a multiscale comparison of spatial heterogeneity under a climate change background. Using improved quantitative evaluation methods of vulnerabil- ity, the Theil index and the Shannon-Weaver index, we evaluated the vulnerability of water resources and its spatial heterogeneity in the Haihe River Basin in four scales, namely, second-class water resource regions （Class II WRRs）, third-class water resource regions （Class III WRRs）, Province-Class II WRRs, and Province-Class III WRRs. Results show that vulnerability enhances from the north to south in the different scales, and shows obvious spatial heterogeneity instead of moving toward convergence in multiscale assessment results. Among the Class II WRRs, the Tuhai-Majia River is the most vulnerable area, and the vulnerability of the Luanhe River is lower than that of the north of the Haihe River Basin, which in turn is lower than that of the south of the Haihe River Basin. In the scales of Class III WRRs and Province-Class III WRRs, the vulnerability shows obvious spatial heterogeneity and diversity measured by the Theil index and the Shannon-Weaver index. Multiscale vulnerability assessment results based on political boundaries and the watersheds of the Haihe River Basin innovatively provided in this paper are important and useful to characterize the real spatial pattern of the vulnerability of water resources and improve water resource management.

流域突发性水环境风险的评估方法

针对突发性水环境风险,提出了以环境敏感受体保护为基础的流域突发性水环境风险评估技术方法。该技术方法充分考虑我国现行突发环境事件分级标准,从我国环境风险管理重点关注的环境敏感受体(如集中式饮用水水源地、行政边界及重要生态保护区域边界)着手,以环境敏感受体保护为最终目的,综合分析流域水环境风险水平,并通过环境风险地图进行表征。本方法统一了固定源和移动源的流域性突发环境风险评估,可用以对流域内存在的固定源和移动源进行全面识别与分级,是我国现有环境风险评估体系的补充,并可为提升我国流域水环境风险管理水平提供参考。

Assessing the Seasonal Predictability of Summer Precipitation over the Huaihe River Basin with Multiple APCC Models

Seasonal rainfall predictability over the Huaihe River basin is evaluated in this paper on the basis of 23-year(1981-2003) retrospective forecasts by 10 climate models from the Asia-Pacific Economic Cooperation(APEC) Climate Center(APCC) multi-model ensemble(MME) prediction system.It is found that the summer rainfall variance in this basin is largely internal,which leads to lower rainfall predictability for most individual climate models.By dividing the 10 models into three categories according to their sea surface temperature(SST) boundary conditions including observed,predicted,and persistent SSTs,the MME deterministic predictive skill of summer rainfall over Huaihe River basin is investigated.It is shown that the MME is effective for increasing the current seasonal forecast skill.Further analysis shows that the MME averaged over predicted SST models has the highest rainfall prediction skill,which is closely related to model's capability in reproducing the observed dominant modes of the summer rainfall anomalies in Huaihe River basin.This result can be further ascribed to the fact that the predicted SST MME is the most effective model ensemble for capturing the relationship between the summer rainfall anomalies over Huaihe River basin and the SST anomalies(SSTAs) in equatorial oceans.

Projection of temperature change and extreme temperature events in the Lancang–Mekong River basin

The Lancang–Mekong River basin(LMRB) is under increasing threat from global warming. In this paper, the projection of future climate in the LMRB is explored by focusing on the temperature change and extreme temperature events. First, the authors evaluate the bias of temperature simulated by the Weather Research and Forecasting model. Then, correction is made for the simulation by comparing with observation based on the non-parametric quantile mapping using robust empirical quantiles(RQUANT) method. Furthermore, using the corrected model results, the future climate projections of temperature and extreme temperature events in this basin during 2016–35, 2046–65, and 2080–99 are analyzed. The study shows that RQUANT can effectively reduce the bias of simulation results. After correction, the simulation can capture the spatial features and trends of mean temperature over the LMRB, as well as the extreme temperature events. Besides, it can reproduce the spatial and temporal distributions of the major modes. In the future, the temperature will keep increasing, and the warming in the southern basin will be more intense in the wet season than the dry season. The number of extreme high-temperature days exhibits an increasing trend, while the number of extreme low-temperature days shows a decreasing trend. Based on empirical orthogonal function analysis, the dominant feature of temperature over this basin shows a consistent change. The second mode shows a seesaw pattern.

Establishing the Basic Indicator for the Calculation of the Flood Vulnerability Index for River Basins in Vietnam

Along with the concept, the method of assessing the vulnerability is becoming more and more diversified in many directions and fields. In general, these methods can be classified into two groups： （i） direct-qualitative （survey methods, integrated map ...） and （ii） indirectly-quantitative （method index）. The set of indicator plays a very important role in the successful application to any method and brings reliable results. Each basin or area with different natural geography, economics and society and so on, requires a different set of indicator. However, assessing any river basin in Vietnam needs the basic indicator. This study will establish the basic indicator for the construction of flood vulnerability index in Vietnam.

An Operational Hydro-Meteorological Chain to Evaluate the Uncertainty in Runoff Forecasting over the Verbano Basin

The development and implementation of a real-time flood forecasting system with a hydro-meteorological operational alert procedure during the MAP-D-PHASE Project is described in this paper. This chain includes both probabilistic and deterministic forecasts. The hydrological model used to generate the runoff simulations is the rainfall-runoff distributed FEST-WB model, developed at Politecnico di Milano. The observed data to run the control simulations were supplied by ARPA-Piemonte. The analysis is focused on Maggiore Lake basin, an Alpine basin between North-West of Italy and Southern Switzerland. Two hindcasts during the D-PHASE period are discussed in order to evaluate certain effects regarding discharge forecasts due to hydro-meteorological sources of uncertainties. In particular, in the June convective event it is analysed how the effect of meteorological model spatial resolution can influence the discharge forecasts over mountain basins, while in the November stratiform event how the effect of the initial conditions of soil moisture can modify meteorological warnings. The study shows how the introduction of alert codes appears to be useful for decision makers to give them a spread of forecasted QDFs with the probability of event occurrence, but also how alert warnings issued on the basis of forecasted precipitation only are not always reliable.

Assessment of Rill Erosion Development during Erosive Storms at Angereb Watershed, Lake Tana Sub-basin in Ethiopia

Application of simple and locally based erosion assessment methods that fit to the local condition is necessary to improve the performance and efficiency of soil conservation practices. In this study, rill erosion formation and development was investigated on the topo-sequence of three catchments （300-500 m slope length）; and on agricultural fields （6 m and 24 m slope lengths） with different crop-tillage surfaces during erosive storms. Rill density and rill erosion rates were measured using rill cross section survey and close range digital photogrammetry. Rill formation and development was commonly observed on conditions where there is wider terrace spacing, concave slope shapes and unstable stone terraces on steep slopes. At field plot level, rill development was controlled by the distribution and abrupt change in the soil surface roughness and extent of slope length. At catchment scale, however, rill formation and development was controlled by landscape structures, and concavity and convexity of the slope. Greater rill cross sections and many small local rills were associated to the rougher soil surfaces. For instance, relative comparison of crop tillage practices have showed that faba-bean tillage management was more susceptible to seasonal rill erosion followed by Teff and wheat tillage surfaces under no cover condition. Surface roughness and landscape structures played a net decreasing effect on the parallel rill network development. This implies that spatial and temporal variability of the rill prone areas was strongly associated with the nature and initial size of surface micro-topography or tillage roughness. Thus, it is necessary to account land management practices, detail micro-topographic surfaces and landscape structures for improved prediction of rill prone areas under complex topographic conditions. Application of both direct rill cross section survey and close range digital photogrammetric techniques could enhance field erosion assessment for practical soil conservation improvement.

Estimation of Pollutant Loads in Ardila Watershed Using the SWAT Model

Abstract： Excess of organic matter and nutrients in water promotes eutrophication process observed in the Ardila River. It was classified as much polluted being critical for Alqueva-Pedrogāo System. The aim of this study was to estimate the transported nutrients loads in a transboundary watershed using the SWAT （soil and water assessment tool） model and to determine the contribution of nutrients load in the entire watershed. Ardila watershed is about 3,711 km^2 extended from Spain （78%） to the eastern part of Portugal （22%）. It was discretized into 32 sub-basins using automated delineation routine, and 174 hydrologic response units. Monthly average meteorological data （from 1947 to 1998） were used to generate daily values through the weather generator Model incorporated in SWAT. Real daily precipitation （from 1931 to 2003） was introduced. The model was calibrated and verified for flow （from 1950 to 2000） and nutrients （from 1981 to 1999）. Model performance was evaluated using statistical parameters, such as NSE （Nash-Sutcliffe efficiency） and root mean square error （R2）. Calibration and verification flow results showed a satisfactory agreement between simulated and measured monthly date from 1962 to 1972 （NSE = 0.8; R^2 = 0.9）. The results showed that the most important diffuse pollution comes from the two the main tributary （Spain）. The estimated nitrogen and phosphorous loads contribution per year was respectively 72% and 59% in Spain and 28% and 41% in Portugal. The SWAT model was revealed to be a useful tool for an integrated water management approach that might be improved taking into count the WFD （water framework directive）.

The Evaluation of Land Use Changes on Stream Discharge by SWAT Model and Remote Sensing in Agro-Forestry Watershed： A Case Study in Nghinh Tuong Subwatershed, Northern Vietnam

The purpose of this paper was to implement ＂Soil and Water Assessment Tool （SWAT）＂ model and Geographic Information System （GIS） to evaluate the impact of land use changes on stream discharge in Nghinh Tuong watershed （a brand of Cau River） in Northern Vietnam. The watershed was coverd by 56% forestry land, 30% agricultural land and the remain 14% for others. Stream discharge observed data from 2002 to 2007 were used for calibration period and from 2008 to 2012 for validation period. The result showed that two coefficients （NSE and PBIAS） to evaluate model performance were 0.76 and 6.54% for calibration period and 0.87 and 4.74% for validation period, respectively. Stream discharge strongly depends not only on quantity of precipitation but also on land use change. Through the scenario 1, agricultural land （corn, orchard and tea） increases 9,782.67 ha （2.45%）, meanwhile forest （forest-mixed） decreases 1,091.77 ha （2.75%） as compared to baseline scenario. Additionally, precipitation increases 3.74% in mean wet season, but decreases 0.5% in mean dry season with respect to baseline period. SWAT model was able to simulate stream discharge and sediment yield for Nghinh Tuong watershed successfully not only for baseline scenario but also for scenario 1. In brief, SWAT proves its ability in simulation stream discharge in subwatershed level. It is a useful tool to assist water quantity and quality management process in Nghinh Tuong watershed. This work one more time indicated that SWAT is useful tool for resources and environment management.

Assessment of Soil Erosion in Mountain Watershed Ecosystems in Tirana-Region

Land erosion is an increasing problem that is seriously affecting our country in recent years. In many areas of our country, mountainous and hilly territories suffer major erosion in both surface and depth, where the solids are deposited in the flat parts of the country, thus leading to a higher content of gravel in agricultural land and filling of the sewage networks. The phenomenon of erosion is greater in the vicinity of residential areas where damages are larger and more sensitive. One of the most vulnerable in our country in terms of soil erosion is the district of Tirana. This study had the main goal to define and categorise of erosion rates in natural environments of the forest economies of the Tirana, the rate of recovery of vegetation, slope and rainfall index, which will serve as information and guidance on the land use by farmers, communes and the state regulatory officials, depending on the ownership of these woodland surfaces.

Assessment of Soil Organic Carbon Stock in the Upper Yangtze River Basin

Soil organic carbon is of great importance to terrestrial ecosystems. Studies on the amount and spatial distribution of soil organic carbon stock in various types of soil can help to better understand the role of soil in the global carbon cycle and provide a scientific basis for the assessment of the magnitude of carbon stored in a given area. Here we present estimates of soil organic carbon stock in soils in the upper reaches of the Yangtze River based on soil types as defined by Chinese Soil Taxonomy and recently compiled into a digital soil database. The results showed that the total soil organic carbon stock of the upper Yangtze River to a depth of 100 cm was 1.452x1013 kg. The highest soil organic carbon stock was found in felty soils （2.419x10TM kg）, followed by dark brown soils （1.269x10=kg）, and dark feltysoils （L139x10=kg）. Chernozems and irrigation silting soils showed the lowest soil organic carbon stock, mainly due to the small total area of such soils. The soil organic carbon density of these major soil types ranged from 5.6 to 26.1 kg m2- The average soil organic carbon density of the upper reaches of the Yangtze River was 16.4 kg m-2, which was higher than that of the national average. Soil organic carbon density indicated a distinct decreasing trend from west to east, which corresponds to the pattern of increasing temperature from cold to subtropical.

Assessment of Soil Erosion Risk in Albania

Albania results are a country with high quantitative level of soil erosion in Europe and elsewhere based on different studies. The amount of soil eroded from the surface water erosion is from 20-40 t/ha/year and in extreme cases results up to 100 t/ha/year from the deepest erosion. This preliminary study will identify the more specific places in order to do more details analyses in the future to take protection measures in highly sensitive places with high erosion risk. This will be a quantitative assessment of places with different level of erosion risks. Further on these results will be generalized at the level of main water basins of Albania. The following main elements of soil erosion assessment are evaluated in this study which include the land cover, slope and density of the hydrologic net.

A Method of Catchments Health Assessment under Value-pressure Model and Its Application in Urbanized River Network Area:A Case Study in Shanghai,China

Catchments health assessment is fundamental to effective catchments management. Generally, an assessment method should be selected to reflect both the purpose of assessment and local characteristics. A trial in Shanghai was conducted to test the method for catchments health assessment in urbanized fiver network area. Seven indicators that described four dimensions of river, river network, land use and function, and local feature were used to assess catchments values; while possible change rate of urbanization and industrialization in the next 3 years were chosen for catchments pressure assessment in the value-pressure model. Factors related to catchments classification, indicators measurement and protection priority have been considered in the development strategies for catchments health management. The results showed that value-pressure assessment was applicable in urbanized catchments health management, particularly when both human and catchments had multiple demands. As a result of over 30-year rapid urbanization, more than 70% of Shanghai fiver network area was still in a healthy condition with high catchments values, among them, 39.3% was under high pressure. Poor water quality, simplified river system and weakened local feature of fiver pattern had largely affected catchments health in Shanghai. Lack of long-term monitoring data would seriously restrict the development and validity of catchments health assessment.