Cui Chen

Impact of a statistical bias correction on the projected hydrological changes obtained from three GCMs and two hydrology models

AbstractFuture climate model scenarios depend crucially on the models’ adequate representation of the hydrological cycle. Within the EU integrated project Water and Global Change (WATCH), special care is taken to use state-of-the-art climate model output for impacts assessments with a suite of hydrological models. This coupling is expected to lead to a better assessment of changes in the hydrological cycle. However, given the systematic errors of climate models, their output is often not directly applicable as input for hydrological models. Thus, the methodology of a statistical bias correction has been developed for correcting climate model output to produce long-term time series with a statistical intensity distribution close to that of the observations. As observations, global reanalyzed daily data of precipitation and temperature were used that were obtained in the WATCH project. Daily time series from three GCMs (GCMs) ECHAM5/Max Planck Institute Ocean Model (MPI-OM), Centre National de Recherches Me...

Developing dynamic virtual geographic environments (VGEs) for geographic research

It has been over 15 years since the concept of Virtual Geographic Environments (VGEs) was formally proposed (Lin and Gong 2001). Although the thinking about VGEs never stops since it was born, and the continued development of VGEs has brought about significant achievements resulting from this concept (e.g., Goodchild 2009; Gong et al. 2010; Konecny 2011; Lu 2011; Priestnall et al. 2012; Lin et al. 2013a, b, 2015) as well as related technologies and implementations (e.g., Xu et al. 2011, 2013; Chen et al. 2012, 2013a, b; Zhang et al. 2015a, b; Zhu et al. 2015), there are still some misunderstandings about this ‘new’ branch of Geoscience. Questions generally are related to two concepts: the first concerns the differences between VGEs and game-like virtual worlds, similar virtual communities and cities, and digital earth; the second asks how VGEs can contribute to geographic research beyond traditional Geographic Information Systems (GIS) and Maps (Aydi et al. 2013; Tung et al. 2013). The answer to the first question may be found in the term ‘geographic environment’ which refers not only to the natural surface of the earth, space, or a place, but also involves the social behaviors that interact with natural factors; it is the sphere of direct interaction between nature and society (Kalesnik 1979). An important feature of geographic environments is that they change continuously with time. Although some objects in geographic environments have relatively stable shapes (such as a rock or soils), many exist in constantly changing forms (such as vegetation, air and water), and human beings (both in groups or individual) are active throughout their ‘lives’. Given this definition, to build a virtual mirror that can reflect the real geographic environment, only considering the physical part would result only in a one-sided perspective. Moreover, dynamic geographic phenomena and processes require careful attention, a fact often overlooked by traditional systems. Thus, an ideal virtual environment

Assessment of impact of climate change on the blue and green water resources in large river basins in China

Climate change as a result of the increased greenhouse gas emissions may influence the availability of water resources in many regions on the globe. In the past decades, China has been facing severe shortage of water resources. This study focuses on the assessment of the impact of climate change on both blue and green water resources in ten large river basins in China. The blue and green water resources for these river basins were derived from the terrestrial hydrological fluxes in period 1960–2100, which were simulated with the Max Planck Institute Hydrological Model—MPI-HM. The forcing data for the hydrological model, the precipitation and temperature were obtained from three coupled Atmosphere–Ocean General Circulation Models (GCMs)—ECHAM5, IPSL and CNRM, under A2 and B1 greenhouse gas emission scenarios. The statistical bias correction method was applied on the output from the three GCMs. By using this climate model–hydrology model modeling chain, the impact of climate change on the blue and green water resources was analyzed over the ten Chinese river basins. Here, the projected changes in 2071–2100 are considered relative to 1971–2000. The projected change of monthly mean and annual mean of green water resources show the general increase for all ten river basins; among them, Inland river, Zhemin river and Zhujiang river have larger change signal than other basins. For blue water resources, increases of the annual mean are projected from November to March for Heilongjiang river, Liaohe river and Yellow river, Inland river in Northern China; and decreases are projected for Huaihe river, Zhemin river, Haihe river, Yangzi river, Southwest river, and Zhujiang river basins in Southern China. It is found that climate change has impact on both blue and green water resources over large river basins in China. The sustainable blue water resources management should take into account the different changes in both Northern and Southern China. The results show that a better management of green water resources is of importance for food and ecological securities in the context of global change.

Thematic issue: water of the Erhai and Dianchi Lakes

Eutrophication of surface waters is a severe problem worldwide (Dimberg and Bryhn 2014; Harmon et al. 2014; Christia et al. 2014; Renjith et al. 2013; Sedlacek et al. 2013; Antunes et al. 2013; Rinke et al. 2013; Watchorn et al. 2013; George et al. 2013; Ivashechkin et al. 2004) but particularly important to China because of the use of water resources from the huge rivers originating in the Tibetan plateau flowing through the North China Plain into the Pacific Ocean. The water quality issue includes nutrients (Ji et al. 2014; Wu et al. 2013) and phosphorus (Chen et al. 2014; Yuan et al. 2014; Zhu et al. 2013; Liu and Chang 2013; Marjore et al. 2013). Recent thematic Issues in EES were dealing with Integrated Water Resources Management under different hydrological, climatic and socio-economic conditions (Kalbus et al. 2012; Grathwohl et al. 2013) including topics like progress in monitoring and modelling concepts (Beinhorn et al. 2005; Beyer et al. 2006; Kalbacher et al. 2012; Rink et al. 2012) and the aquatic ecosystem functions (the harm of microcystis aeruginosa, role of macrophytes in ecological water treatment (Li et al. 2015a, b, c), see below). ‘‘Microcystis aeruginosa is a species of freshwater cyanobacteria which can form harmful algal blooms of economic and ecological importance (Huo et al. 2015). Microcystis are the most common toxic cyanobacterial bloom in eutrophic fresh water. Cyanobacteria produce several groups of toxins, neurotoxins and peptide hepatotoxins, such as microcystin and cyanopeptolin’’. Several case studies have been reported recently in EES. Huang et al. (2014) investigated algal bloom and factors influencing its formation in Taihu Lake from 2000 to 2011. Thi Thuy et al. (2014) studied the occurrence of cyanobacteria and microcystins in the Hoan Kiem Lake and the Nui Coc reservoir (North Vietnam). Macrophytes are aquatic plants that grow in or near water and are emergent, submergent, or floating. In lakes and rivers macrophytes provide cover for fish and substrate for aquatic invertebrates, produce oxygen and act as food for some fish and wildlife. Several case studies have been reported recently in EES from Brazil, India and Greece. Goldoni et al. (2014) investigated cytotoxic and genotoxic evaluation and chemical characterization of sewage treated using activated sludge and a floating emergent-macrophyte filter in a municipal wastewater treatment plant in Southern Brazil. Christia et al. (2014) studied seasonal and spatial variations of water quality, substrate and aquatic macrophytes based on side scan sonar, in an eastern Mediterranean lagoon (Kaiafas, Ionian Sea). Anshumali et al. & Olaf Kolditz ees-editor@ufz.de

German contributions to the Major Water Program in China: “Innovation Cluster–Major Water”

Within the German research initiative CLIENT (International Partnerships for Sustainable Technologies and Services for Climate Protection and the Environment that is funded by the German Federal Ministry of Education and Research, BMBF), several projects started recently to support China in solving the water problems in selected areas: SINOWATER (Dian Lake and Liao River), SIGN (Tai Lake) and Urban Catchments (Chao Lake). These German–Chinese cooperation projects by BMBF and the Chinese Ministry of Science and Technology (MoST) officially started with the inauguration event held on 7 May 2015 in Beijing where a joint declaration between the Chinese and German ministries was signed.

Virtual geographic environments for water pollution control

ABSTRACT Due to extensive water pollution in Chinese rivers and lakes, large efforts have to be made to improve the quality of drinking water and manage the sewage water treatment process. We propose a general workflow for integrating a large number of heterogeneous data sets relating to various hydrological compartments into a Virtual Geographic Environment (VGE). This allows both researchers and stakeholders to easily access complex data collections in a unified context, find interrelations or inconsistencies between data sets and evaluate simulation results with respect to other observations or simulations in the same region. A prototype of such a VGE has been set up for the region around Chao Lake, containing more than 20 spatial data sets and collections as well as first simulation result. The prototype has been successfully presented to researchers and stakeholders from China and Germany.

Social–ecological challenges in the Yellow River basin (China): a review

The human–environment relationship within the Yellow River basin has a long history, because favorable environmental circumstances allowed the early emergence of societies along the river banks, and hence, the Yellow River basin was the birthplace of ancient Chinese civilization. On the other hand, the Yellow River is “China’s sorrow” due to the constant occurrences of flooding events throughout history. In recent decades, the Yellow River basin is facing a spectacular economic boom, but mainly achieved at the expenses of the environment by over-exploiting the natural resources provided within the basin, which causes various challenges on ecology and society. Water scarcity, pollution, and ecosystem degradation accompanied with biodiversity decline have been further aggravated by anthropogenic-induced climate change. To address the pressing socio-ecological challenges, various conservation and management plans and strategies have been issued, often consulted by international bodies. This article is a comprehensive overview of the current state and recent developments that have occurred in the Yellow River basin and presents and discusses current and pressing socio-ecological challenges. Additionally, we address different policy and management instruments that have been launched to ensure a long-term sustainable development within the basin.

Persistent organic pollutants contaminate Chinese water resources: overview of the current status, challenges and European strategies

In order to get a better overview of the national scale of POP-related water pollution in China, the EU-China Environmental Sustainability Programme of the European Union and the international Helmholtz network, RCEIS, are supporting the enormous task of compiling data on existing individual contaminant investigations of rivers, lakes and aquifers in China. The differences regarding POP contamination in the water body status evaluation schemes of China and the EU become evident as the authors point out a selection of European case studies of POP-contaminated water resource assessments and successful remediation strategies. An ongoing cooperation project between China and the EU is introduced to show exemplarily that the adoption of existing strategies will offer huge potential opportunities for China to manage its water quality challenges and to enhance the existing scientific cooperation between China and the EU.

Design and integration of a GIS-based data model for the regional hydrologic simulation in Meijiang watershed, China

This paper presents the design and integration of a GIS-based data model for the regional hydrologic simulation in the Meijiang watershed, China. Hydrologic systems (HS) require integration of data and models simulating different processes. Here, an object-oriented approach using Unified Modeling Language (UML) is introduced, which supports the development of GIS-based Geodatabase model—GeoHydro/DataBase (GH/DB). Spatial data, such as basins, stream network, and observation stations are stored in the feature classes. The time series and their attributes are included in the tables. Relationship classes are used to link associated objects. The new development within the scientific program OpenGeoSys (OGS) is the integration of GH/DB into the numerical simulations. The graphical user interface is implemented for the pre- and post-processing of the simulation. As for the case study, a regional hydrologic model is developed in the Meijiang watershed area for the understanding of water infiltration from surface into groundwater via soil layer with various time scales. The integration of databases and modeling tool represents the comprehensive hydrosystems and thus it is a useful tool to understand the different processes and interactions between the related hydrological compartments.

Thematic Issue: Environment and Health in China—I

Combining and solving environment and health is a major issue in China—a country with tremendous economic development perspectives. Recent developments (e.g., the Tianjin Harbor accident in August 2015) show that China is investing more and more resources and efforts to cope with the industrial development (GDP) into alliancing with environmental safeguarding. The Thematic Issue on Environment and Health in China is a starting point for discussion of a variety of environmental issues, such as distribution and fractionation of rare earth elements in soil–water system and human blood (Li et al. 2014a, b, c, d); spatial evaluation of phosphorus retention in riparian zones using remote sensing data concerning the big and scarce data issues (Dong et al. 2014); toxicity contamination and distribution in soils and plants (Li et al. 2014a, b, c, d); the status and challenges of water pollution problems in China: learning from the European experience (Zhou et al. 2014); the Heihe River basin (Xiao et al. 2014), identifying interactions between river water and groundwater in the North China Plain using multiple tracers (Dun et al. 2014); potential hazardous elements (PHEs) in atmospheric particulate matter (APM) in the south of Xi’an during the dust episodes of (2001–2012) chemical fractionation; ecological and health risk assessment (Li et al. 2014a, b, c, d), occurrence and hydrogeochemistry of fluoride in alluvial aquifer of Weihe River (Li et al. 2014a, b, c, d); contamination assessment and health risk of heavy metals in dust from Changqing industrial park of Baoji (Wang et al. 2014a, b); contamination assessment and health risk of heavy metals in dust from Changqing industrial park of Baoji (Su et al. 2014); sources and transports of polycyclic aromatic hydrocarbons in the Nanshan Underground River, China (Alam et al. 2014); introducing a land-use-based spatial analysis method for human health risk evaluation of soil heavy metals (Wang et al. 2013a, b, c);