Hydropower-induced land use change in Fincha's watershed, werstern Ethiopia: analysis and impacts

The present article analyzes the land use dynamics caused by hydropower dam construction in 1973 in the Fincha'a watershed (1318 km2), a tributary of the Blue Nile. Aerial photos (1957 and 1980) and an ASTER satellite image of 2001 were used to make 3 land use maps of the watershed using a geographic information system (GIS). The 239-km2 water reservoir inundated 100 km2 of grazing land, 120 km2 of swamp, 18 km2 of cropland, and 1.2 km2 of forestland. In 2001, cropland covered 77% of the land potentially available for community use, indicating that there is hardly any free land available for expansion to accommodate new farmers. Relocated communities operate on relatively small parcels of land situated either on steep slopes or in flood-prone areas. Consequently, they exhaustively utilize the trees available on their holdings, and convert grassland and bush-land to cropland, without applying sufficient soil conservation measures. Farmers resettled at or near bodies of water and swamps, however, are affected by seasonal fluctuations of water levels that very often inundate croplands, grazing land, and homes. The demand for cropland and grazing land is increasing as reservoir and swamp areas expand and new families are created. Soil erosion in steep areas can no longer be reduced in the traditional farming system. These enforced land use changes, combined with a lack of appropriate land management practices, may increase erosion and reservoir sedimentation. This could affect food security and electric power production in the near futur

Spatial epidemiology in zoonotic parasitic diseases: insights gained at the 1st International Symposium on Geospatial Health in Lijiang, China, 2007

The 1st International Symposium on Geospatial Health was convened in Lijiang, Yunnan province, People's Republic of China from 8 to 9 September, 2007. The objective was to review progress made with the application of spatial techniques on zoonotic parasitic diseases, particularly in Southeast Asia. The symposium featured 71 presentations covering soil-transmitted and water-borne helminth infections, as well as arthropod-borne diseases such as leishmaniasis, malaria and lymphatic filariasis. The work made public at this occasion is briefly summarized here to highlight the advances made and to put forth research priorities in this area. Approaches such as geographical information systems (GIS), global positioning systems (GPS) and remote sensing (RS), including spatial statistics, web-based GIS and map visualization of field investigations, figured prominently in the presentation

Using scenario modelling for adapting to urbanization and water scarcity: towards a sustainable city in semi-arid areas

Sustainable development on a global scale has been hindered by urbanization and water scarcity, but the greatest threat is from decision-makers ignoring these challenges, particularly in developing countries. In addition, urbanization is spreading at an alarming rate across the globe, affecting the environment and society in profound ways. This study reviews previous studies that examined future scenarios of urban areas under the challenges of rapid population growth, urban sprawl and water scarcity, in order to improve supported decision-making (SDM). Scholars expected that the rapid development of the urbanization scenario would cause resource sustainability to continually be threatened as a result of excessive use of natural resources. In contrast, a sustainable development scenario is an ambitious plan that relies on optimal land use, which views land as a limited and non-renewable resource. In consequence, estimating these threats together could be crucial for planning sustainable strategies for the long term. In light of this review, the SDM tool could be improved by combining the cellular automata model, water evolution and planning model coupled with geographic information systems, remote sensing and criteria analytic hierarchical process modelling. Urban planners could optimize, simulate and visualize the dynamic processes of land-use change and urban water, using them to overcome critical conditions

Time and space model of urban pollution migration: Economy-energy-environment nexus network

In recent years, news of “cancer villages” in the Huaihe River Basin filled front and back pages of newspapers and generated elevated concern among readers. This study aims to understand the relationship between the “cancer villages” and the “large cities” around them. A gravity model is constructed to analyze the correlation between “big cities” and “cancer villages” in terms of indices involving economic connections and pollution frequency. Direct and indirect environmental relationships between large cities and “cancer villages” are analyzed using ecological network analysis, in particular the utility analysis method. Results of the pollution-utility analysis showed that cities distant from “cancer villages” can also affect the county through indirect connections. Based on the pollution utility relationship, we found that “cancer villages” both affect and are affected by cities through indirect feedback relationships. It can be inferred that “cancer villages” have a high incidence of malignant disease not only because of the pollution from its surrounding cities but also because of the influence of far-away cities through a network of interactions. In this way, the pollution of “cancer villages” may be heightened with harmful consequences to population health. Considering these indirect connections, not all of the “cancer villages” are able to reduce their pollution by transferring it to another city or county because it can return through indirect pathways. The best approach would be to lower the pollution generation in the first place in order to prevent its impacts, as well as to at least partially mitigate them through more effective medical care

Exploration of eco-environment and urbanization changes in coastal zones: A case study in China over the past 20 years

Abstract With the rapid development of urbanization and population migration, since the 20th century, the natural and eco-environment of coastal areas have been under tremendous pressure due to the strong interference of human response. To objectively evaluate the coastal eco-environment condition and explore the impact from the urbanization process, this paper, by integrating daytime remote sensing and nighttime remote sensing, carried out a quantitative assessment of the coastal zone of China in 2000–2019 based on Remote Sensing Ecological Index (RSEI) and Comprehensive Nighttime Light Index (CNLI) respectively. The results showed that: 1) the overall eco-environmental conditions in China's coastal zone have shown a trend of improvement, but regional differences still exist; 2) during the study period, the urbanization process of cities continued to advance, especially in seaside cities and prefecture-level cities in Jiangsu and Shandong, which were much higher than the average growth rate; 3) the Coupling Coordination Degree (CCD) between the urbanization and eco-environment in coastal cities is constantly increasing, but the main contribution of environmental improvement comes from non-urbanized areas, and the eco-environment pressure in urbanized areas is still not optimistic. As a large-scale, long-term series of eco-environment and urbanization process change analysis, this study can provide theoretical support for mesoscale development planning, eco-environment condition monitoring and environmental protection policies from decision-makers

Twenty Years of Working Towards a Sustainable Southeast Asia: 1993 -- 2013

The Southeast Asia program first set about testing hypotheses applicable to each of the three ecosystem zones. On the forest margins, the hypothesis was that complex agroforests provided a superior alternative for small-scale farmers to either food-crop systems or monocultural plantations of perennials. As an alternative to slash and burn, complex agroforests increased production sustainability, increased biodiversity, reduced production risks and increased returns to labour compared to continuous food crops or monocultural plantations. The second hypothesis stated that rehabilitating Imperata grasslands with small-scale agroforestry systems would be superior to plantation reforestation in terms of production, equitability and participation. For hilly farmlands, the team hypothesised that there were several pathways to sustainable farming. Among these, contour hedgerow systems initiated through natural vegetative strips provided distinct advantages as a superior, least-cost foundation upon which to build agroforestry-based, conservation farming

Spatial assessment and management of regional ecosystem services in the Yangtze River Delta Region

The Yangtze River Delta (YRD) metropolitan region is one of the most rapidly urbanized regions in China and has experienced a remarkable period of population growth (at an annual growth rate of 3.0%), and urbanization (at an annual growth rate of 9.2%). Rapid urbanization has dramatically changed land use/land cover patterns and ecosystems in the region, causing widespread environmental problems such as habitat fragmentation, aggravation of environmental pollution, decline in biodiversity and ecosystem degredation. These problems have restricted the sustainable development of socio-economic system of the Yangtze River Delta Region. Facing the challenges, the Yangtze River Delta Region is carrying out the practice of regional integration planning and cooperation in environmental governance, which urgently needs the guidance of relevant theories and methods. Some of the key environmental policy pilots have been carried on in this region, such as the Ecological Red Line Policy (Bai et al, 2016; Lü et al, 2013). This policy has one of the main objectives of protecting important eco-function areas i.e. ecosystem service hot spots, to deliver services such as water storage, clean drinking water, and carbon sequestration, and to maintain ecological safety to support economic and social development, which an important policy orientation of ecosystem services approach.Ecosystem services are the contributions of ecosystem structure and function to human well-being, connecting natural and socio-economic systems. The ecosystem services approach is considered to be one of the important decision support tools for guiding and formulating environmental policies. Based on the theories and methods of ecosystem services, combined with local expert knowledge, remote sensing and GIS technologies, this dissertation aims is mainly to develop a comprehensive framework of ecosystem services assessment and decision support for rapid urbanization regions.Based on this framework, the spatial characteristics, supply-demand relationship and flow direction of ecosystem services in the Yangtze River Delta Region are analysed and evaluated. Main results of this thesis are as follows:(1) According to the characteristics of the regional ecosystems of the Yangtze River Delta Region, combined with local expert knowledge, the Burkhard’s scoring and assessment method of ecosystem services was improved, and the score matrix between twelve ecosystem types and twenty-three ecosystem services in the Yangtze River Delta Region was established.(2) Based on DPSIR model, the characteristics of the social-ecological complex ecosystem and change of ecosystem services in the Yangtze River Delta Region were analysed. The main ecological and environmental problems were identified. Causes and main driving forces of decline in ecosystem services were revealed in the region.(3) Based on ARCGIS platform, the status quo of ecosystem services in the Yangtze River Delta region was analysed and evaluated. The spatial differentiation characteristics and main impact factors of ecosystem services in the Yangtze River Delta region were clarified. The hot spots of total ecosystem services were aggregated in the southwest areas, while the cold spots were distributed in the middle and northeast areas of the region. The hot spots of supporting services and regulating services aggregately distributed in the southwest mountainous areas while hot spots of provisioning services mainly in the northeast plain, and high value of cultural services widespread in the waterbodies and southwest mountainous areas. The spatial heterogeneity is determined by biophysical features and land use types. Based on the assessment, six major ecosystem services functional zones were divided: (I) South Ecological Integrity Conservation Zone, (II) Southwest Mountainous and Hilly Forest Ecological Zone, (III) Northeast Plain Agriculture Ecological Zone, (IV) Middle Aquatic Ecological Conservation Zone, (V) Eastern Coastal Estuaries Ecological Zone, and (VI) Urban Development Area., and the corresponding management strategies on the basis of environmental problems and ecosystem services characteristics in each of the functional zones were put forward.(4) Using regional spatial data in net primary productivity, the quality levels of forest and cropland were graded and the previous scores of ecosystem services in forest and cropland were calibrated. Then, the hot spots and clustering patches of forest and farmland ecosystem services were identified by ARCGIS tools. Finally, the forest ecosystem conservation areas (red line) and cropland ecosystem conservation areas (red line) in the Yangtze River Delta region were delineated.(5) Based on the improved Burkhard’s supply-demand budget of ecosystem services method, the budgets of three regulating services (erosion regulating service, flood regulating service and water purification regulating service) of the sixteen core cities in the region were established, and the characteristics of surplus and deficit of three services of the cities in the region were analysed. Combing the budget with analysis of flow direction of ecosystem services, the potential provisioning cities and the benefiting cities of ecosystem services are identified. On the basis of the results, the potential model of regional inter-city environmental cooperation is proposed.This dissertation not only improves the methods of ecosystem service assessment and decision support in rapidly urbanized regions, but also makes contributions to the guidance in delineation of ecological red line, regional environmental cooperation and sustainable development in the Yangtze River Delta Region

Ecohealth research in Southeast Asia : past, present and the way forward

Ecohealth is a comprehensive approach to understanding health at its human, animal and environmental interface in a socio-ecological systems context. This approach was introduced widely in Southeast Asia (SEA) by the Canadian International Development Research Centre (IDRC) in the late 2000s. Aimed at addressing the problem of emerging infectious diseases (EIDs), numerous such projects and activities have been generated throughout the region. Ecohealth is increasingly converging with the One Health approach, as both movements emphasise a holistic understanding to health. We conducted a scoping review by considering all of the Ecohealth programmes, initiatives and projects that have been implemented in SEA since the introduction of the approach, and also gathered information from peer-reviewed literature. The objective of this paper is to review Ecohealth activities within SEA over the last 10 years to address the lessons learned, challenges faced and the way forward for Ecohealth in the region. Activities range from those focusing purely on capacity, projects focusing on research and projects covering both. Achievements to date include, for example, research contributing to the field of infectious diseases in relation to social ecological factors and associated urbanisation and agricultural intensification. Challenges remain at the project design and implementation level, in the available capacity and coordination to develop Ecohealth research teams in the countries, gauging teams' assimilation of Ecohealth's underlying tenets and their translation into sustainable disease prevention and control, as well as in the ability to scale up Ecohealth projects. We suggest that the way forward for Ecohealth should be from a regional perspective in terms of research, training and policy translation using Ecohealth in combination with the One Health approach