Oasis land-use change and its effects on the eco-environment in Yanqi Basin, Xinjiang, China

Satellite data and the published coefficients about the world's and China's ecosystem were used to analyze the effects of land-use changes on the ecosystem service in the Yanqi Basin. Both economic developments and arid, fragile ecosystems have strongly affected the land use. A sensitivity analysis determined the effect of manipulating the coefficients on the estimated values. Results indicated that (1) the total value of ecosystem services in the Yanqi Basin were 9,374.66, 10,450.52, 9,964.20, and 9,8707.77 million Yuan in 1990, 2000, 2005, and 2011, respectively. The net increase in ecosystem service values were about 496.11 million Yuan within 1990–2011; (2) The aggregated ecosystem service values of water body, wetlands, grasslands, and croplands were about 99.25 % of the total value; (3) Waste treatment and soil formation were the top two ecological functions with high service values and contributing about 61.70 % of the total service values; and (4) Ecosystem service values estimated in this study were inelastic with respect to the value coefficients; therefore, the estimation was robust in spite of uncertainties on the value coefficients. A reasonable land-use plan should be based on rigorous environmental impact analyses for maintaining stability and sustainable development of the Yanqi Basin.     

Land use/land cover change and their effects on landscape patterns in the Yanqi Basin, Xinjiang (China)

Human modification of land use and land cover change (LUCC) drives the change of landscape patterns and limits the availability of products and services for human and livestock. LUCC can undermine environmental health. Thus, this study aimed to develop an understanding of LUCC in the Yanqi Basin, Xinjiang, China, an arid area experiencing dramatic water and land resource use. A time series of satellite images (1964, 1973, 1989, 1999, and 2009) were used to calculate the index of landscape patterns to study the processes involved in changes to land uses and landscape patterns and the influence of this changes on landscape patterns. The results show that land uses in the Yanqi Basin have changed dramatically since 1964 with grassland being mainly converted to cropland. Landscape fragmentation and diversity have decreased in the study area, although landscape fragmentation increased from 1964 to 1999 and then decreased by 2009. The index of landscape diversity decreased from 1.64 in 1964 to 0.71 in 2009. The heterogeneity and complexity of the landscape increased during this period. In contrast, the index of dominance decreased from 0.85 in 1964 to 0.83 in 2009. Land use change drives landscape patterns of the development of the watershed toward diversity and a fragmented structure. Population growth, economic development, and industrial policies were the dominant driving forces behind LUCC in the Yanqi Basin. Sustainable use of land resources is a significant factor in maintaining economic development and environmental protection in this arid inland river basin.     

Land use pattern, socio-economic development, and assessment of their impacts on ecosystem service value: study on natural wetlands distribution area (NWDA) in Fuzhou city, southeastern China

This paper quantifies the allocation of ecosystem services value (ESV) associated with land use pattern and qualitatively examined impacts of land use changes and socio-economic factors on spatiotemporal variation of ESV in the Natural Wetland Distribution Area (NWDA), Fuzhou city, China. The results showed that total ESV of the study area decreased from 4,332.16?×?10⁶ RMB Yuan in 1989 to 3,697.42?×?10⁶ RMB Yuan in 2009, mainly due to the remarkable decreases in cropland (decreased by 55.3 %) and wetland (decreased by 74.2 %). Forest, water, and wetland played major roles in providing ecosystem services, accounting for over 90 % of the total ESV. Based on time series Landsat TM/ETM+ imagery, geographic information system, and historical data, analysis of the spatiotemporal variation of ESV from 1989 to 2009 was performed. It indicated that rapid expansion of urban areas along the Minjiang River resulted in significant changes in land use types, leading to a dramatic decline in ecosystem services. Meanwhile, because of land scarcity and unique ecosystem functions, the emergency of wetland and cropland protection in built-up area has become an urgent task of local authorities to the local government. Furthermore, there was still a significant negative correlation between ESV of cropland and wetland and the GDP. The results suggest that future planning of land use pattern should control encroachment of urban areas into cropland and wetland in addition to scientific and rational policies towards minimizing the adverse effects of urbanization.     

Impact of land use and land cover changes on ecosystem services in Menglun, Xishuangbanna, Southwest China

Changing the landscape has serious environmental impacts affecting the ecosystem services, particularly in the tropics. In this paper, we report changes in ecosystem services in relation to land use and land cover over an 18-year period (1988--2006) in the Menglun Township, Xishuangbanna, Southwest China. We used Landsat TM/ETM and Quickbird data sets to estimate changes in ten land use and land cover categories, and generalized value coefficients to estimate changes in the ecosystem services provided by each land category. The results showed that over the 18-year period, the land use and land cover in the study area experienced significant changes. Rubber plantations increased from 12.10% of total land cover to 45.63%, while forested area and swidden field decreased from 48.73 and 13.14 to 27.57 and 0.46%, respectively. During this period, the estimated value of ecosystem services dropped by US $11.427 million (approximately 27.73%). Further analysis showed that there were significant changes in ecological functions such as nutrient cycling, erosion control, climate regulation and water treatment as well as recreation; the obvious increase in the ecological function is provision of raw material (natural rubber). Our findings conclude that an abrupt shift in land use from ecologically important tropical forests and traditionally managed swidden fields to large-scale rubber plantations result in a great loss of ecosystem services in this area. Further, the study suggests that provision of alternative economic opportunities would help in maintaining ecosystem services and for an appropriate compensation mechanisms need to be established based on rigorous valuation.     

Changes of Land Use and of Ecosystem Service Values in Sanjiang Plain, Northeast China

Agricultural activities, especially reclamation, are considered major threats to the wetland ecosystems in Sanjiang Plain, the largest concentrated area of the freshwater wetlands in China. In the past decades, the area of the cultivated land and its grain production have been increased at the cost of wetlands shrinkage. The large-scale land reclamation severely affected the ecosystems in this region. However, such effects at the regional scale are seldom evaluated quantitatively. We used three datasets of LANDSAT MSS and/or TM imagery to estimate the area changes and the transition of land use types from 1980 to 2000. We also valued changes in ecosystem services delivered by each land category using value coefficients published by Costanza et al. [Nature 387, 1997, 253–260]. Sensitivity analysis suggested that these estimates were relatively robust. Finally, the contribution of various ecosystem functions was ranked to the overall value of the ecosystem services in this study. According to our estimates, the total annual ecosystem service values in Sanjiang Plain have declined by about 40% between 1980 and 2000 ($156284–182572.18 million in total over 20 years). This substantial decline is largely attributed to the 53.4% loss of wetlands. For individual ecosystem functions, waste treatment, water supply and disturbance regulation account for more than 60% to the total ecological values. During those two decades, the contribution of disturbance regulation, cultural and recreation decreased, while the contribution of water regulation, nutrient cycling, food production, raw materials and climate regulation increased during the same period. We also put forward a few proposals concerning the future land use policy formulation and sustainable ecosystems. They are adjusting the ‘food first’ agricultural policy, establishing more nature reserves for wetlands, creating systems for the rational use of water, harnessing the degraded cultivated land and encouraging eco-tourism.     

银川市城市生态服务功能价值的变化分析

生态系统服务价值的研究是目前生态学研究的热点之一。本文基于生态系统服务功能价值理论，根据银川市土地利用变化的情况，定量估算了其土地生态系统为人类提供服务的经济价值。结果表明，1996—2006年银川市生态系统服务价值变化的总态势是先增后减，生态系统服务功能在城市化过程中受到较大的影响。     

Impact of socioeconomic development on ecosystem services and its conservation strategies: a case study of Shandong Province,China

Ecosystems and their components provide a lot of benefits for the welfare of human beings. Coupled with increasing socioeconomic development, most of the rapidly developing and transitional countries and regions have been experiencing dramatic land use changes. This has resulted in a large amount of forestland, grassland, and wetland being occupied as residential and industrial land or reclaimed for arable land, which in turn results in a sharp deterioration of ecosystem services around the world. Shandong Province, an economically powerful province of China, was chosen as a case study in order to capture the impact of socioeconomic development on ecosystem services. By way of the study, land uses and their changes were categorized between 1980 and 2006, and the ecosystem services capital and changes of 111 counties of Shandong Province in different phases were evaluated, as well as the total ecosystem services capital, followed by the zoning of ecosystem services function region of Shandong Province. We found that the counties in mountainous areas and wetlands, where generally the prefectural-level cities are located with a rapid socioeconomic development, experienced a successive deterioration of ecosystem services especially during the 2000s. Finally, three conservation strategies for managing and improving ecosystem services were proposed and discussed with the aim of achieving coordinate and sustainable development of the socioeconomy, environment, and ecosystems not only in Shandong Province but also in other provinces of China, as well as in other developing and transitional countries and regions.     

Quantification of the Impact of Land-Use Changes on Ecosystem Services: A Case Study in Pingbian County, China

Pingbian Miao Autonomous County is one of the poorest rural areas in China. Land-use changes, mainly driven by agricultural expansion and deforestation, may significantly impact ecosystem services and functions, but such effects are difficult to quantify. In the present study, Landsat image data were combined with the published coefficients about the world and China ecosystem to quantify land-use and ecosystem service changes in the mountainous area. A sensitivity analysis was employed to determine the effect of manipulating these coefficients on the estimated values. Our results show that during the past decades (from 1973 to 2004) forests and grasslands were converted into shrubland and cropland, respectively, resulting in a continuous decrease in ecosystem service (from 124.5 US$ × 10⁶ in 1973 to 100.4 US$ × 10⁶ in 2004). We found that the decrease of mixed forest in the study area was the largest contributor (i.e., 25.4 US$ × 10⁶) to the decline of the ecosystem service. Therefore we propose that future land-use policy should pay more attention to the crucial ecosystem functions of these forests (including tropical forest), and that it is necessary to balance the relationship between the livelihood of local farmers and environmental protection in order to maintain a healthy and stable ecosystem.     

基于改进生态价值当量的长株潭地区生态补偿空间选择

以长株潭地区为研究对象,基于改进生态价值当量计算研究区域的生态系统服务价值,结合区域经济社会发展水平探讨研究区域的生态补偿优先级,并以2002年、2008年、2014年作为典型年份研究长株潭地区生态补偿的空间选择。研究表明:长株潭地区2002—2014年间生态系统服务价值(ESV)呈现持续下降趋势。通过敏感性分析可知,长株潭地区生态系统服务总价值对于价值系数相对稳定,研究结果可信。长株潭地区各县(市、区)的生态服务价值和生态补偿优先级存在较大的空间差异,2014年度长沙市、株洲市、湘潭市市辖区域及长沙县、望城区应率先进行生态支付。     

Climate change impacts detection in dry forested ecosystem as indicated by vegetation cover change in —Laikipia,of Kenya

The objective of the study was to detect and identify land cover changes in Laikipia County of Kenya that have occurred during the last three decades. The land use types of study area are six, of which three are the main and the other three are the minor. The main three, forest, shrub or bush land and grassland, changed during the period, of which grasslands reduced by 5864 ha (40%), forest by 3071 ha (24%) and shrub and bush land increased by 8912 ha (43%). The other three minor land use types were bare land which had reduced by 238 ha (45%), river bed vegetation increased by 209 ha (72%) and agriculture increased by 52 ha (600%) over the period decades. Differences in spatiotemporal variations of vegetation could be largely attributed to the effects of climate factors, anthropogenic activities and their interactions. Precipitation and temperature have been demonstrated to be the key climate factors for plant growth and vegetation development where rainfall decreased by 200 mm and temperatures increased by 1.5 °C over the period. Also, the opinion of the community on the change of land use and management was attributed to climate change and also adaptation strategies applied by the community over time. For example unlike the common understanding that forest resources utilisation increases with increasing human population, Mukogodo dry forested ecosystem case is different in that the majority of the respondents (78.9%) reported that the forest resource use was more in that period than now and also a similar majority (74.2%) had the same opinion that forest resource utilisation was low compared to last 30 years. In Yaaku community, change impacts were evidenced and thus mitigation measures suggested to address the impacts which included the following: controlled bush management and indigenous grass reseeding programme were advocated to restore original grasslands, and agricultural (crop farming) activities are carried out in designated areas outside the forest conservation areas (ecosystem zoning) all in consultation with government (political class), community and other stakeholders. Groups are organised (environmental management committee) to address conservation, political and vulnerability issues in the pastoral dry forested ecosystem which will sustain pastoralism in the ecosystem.     

Assessing land take by urban development and its impact on carbon storage: Findings from two case studies in Italy

Land take due to urbanization triggers a series of negative environmental impacts with direct effects on quality of life for people living in cities. Changes in ecosystem services are associated with land take, among which is the immediate C loss due to land use conversion. Land use change monitoring represents the first step in quantifying land take and its drivers and impacts. To this end, we propose an innovative methodology for monitoring land take and its effects on ecosystem services (in particular, C loss) under multi-scale contexts. The devised approach was tested in two areas with similar sizes, but different land take levels during the time-span 1990–2008 in Central Italy (the Province of Rome and the Molise Region). The estimates of total coverage of built up areas were calculated using point sampling. The area of the urban patches including each sampling point classified as built up areas in the year 1990 and/or in the year 2008 is used to estimate total abundance and average area of built up areas. Biophysical and economic values for carbon loss associated with land take were calculated using InVEST.Although land take was 7–8 times higher in the Province of Rome (from 15.1% in 1990 to 20.4% in 2008) than in Molise region, our findings show that its relative impact on C storage is higher in the latter, where the urban growth consistently affects not only croplands but also semi-natural land uses such as grasslands and other wooded lands. The total C loss due to land take has been estimated in 1.6 million Mg C, corresponding to almost 355 million €.Finally, the paper discusses the main characteristics of urban growth and their ecological impact leading to risks and challenges for future urban planning and land use policies.     

Impact of urbanization on natural ecosystem service values: a comparative study

With rapid population growth and rural to-urban migration in many Chinese cities, a large amount of natural lands have been converted to urban and agricultural lands recently. During this process of land conversion, economic development and quality of life improvement are considered as major goals, and their influences on ecological systems have often been neglected. The degradation of natural ecological systems due to land use change, however, has become severe,and may require immediate attentions from urban planners and local governments. Taking HaDaQi industrial corridor, Heilongjiang Province, China,as a case study area, this paper examined the trend of land use changes during 1990–2005, and quantified their influences on natural eco system service values. In particular, this study applied two major valuation methods, and examined whether different valuation methods generate significantly different results. Analysis of results suggests that human dominated land uses (e.g., urban and agriculture)have expanded rapidly at the cost of natural lands (e.g., wetlands and forest). Due to these land use changes, the total ecosystem service value decreased 29% (2.26% annually) from 1990 to 2005 when the first method was applied, and this rate is estimated to be 15.7% (1.13% annually)with the second approach. Moreover, the annual rate of ecosystem service value decline during 2000–2005 is about four times higher than that in 1990–2000 with both methods, suggesting much more severe ecosystem degradation during 2000–2005.     

A Landscape Ecology Assessment of the Tensas River Basin

A group of landscape ecological indicators were applied to biophysical data masked to the Tensas River Basin. The indicators were used to identify and prioritize sources of nutrients in a Mississippi/Atchafalaya River System sub-basin. Remotely sensed data were used for change detection assessment. With these methods, we were able to look at land use practices over the past twenty years in the Tensas River Basin of Louisiana. A simple land use classification was applied to multispectral scanner (MSS) data from 1972 and 1991. The landscape analysis methods described in this paper will show how to use these methods to assess the impact of human land use practices that are being implemented to improve environmental quality. Landscape assessment methods can be used as a simple, timely, cost effective approach for monitoring, targeting, and modeling ecosystem health in watersheds. Although this study was conducted in the southeast, the methods described in this paper may be applicable to western landscapes.     

Assessing the impact of alternative land-use zoning policies on future ecosystem services

Land use conversions rank among the most significant drivers of change in ecosystem services worldwide, affecting human wellbeing and threatening the survival of other species. Hence, predicting the effects of land use decisions on ecosystem services has emerged as a crucial need in spatial planning, and in the associated Strategic Environmental Assessment (SEA) practice. The paper presents a case-study research aimed at empirically exploring how the implementation of different land-use zoning policies affect the future provision of a set of ecosystem services (water purification, soil conservation, habitat for species, carbon sequestration and timber production). The study area is located in The Araucanía, one of Chile's Administrative Regions. The first part of the methods consisted in the construction of land-use scenarios associated to different policies. Subsequently, the effects of the land-use scenarios on the provision of the selected ecosystem services were assessed in a spatially explicit way, by using modeling tools. Finally, a set of metrics was developed to compare scenarios, and trade-offs in the provision of different ecosystem services were made explicit through trade-off curves. The results indicate that, for this case study, spatial configuration of land uses is as an important factor as their size. This suggests that the analysis of land-use patterns deserves attention, and that this information should be included in scenario exercises aimed to support spatial planning. The paper concludes by discussing the potential contribution of the approach to support SEA of spatial plans.     

Oasis land-use change and its environmental impact in Jinta Oasis, arid northwestern China

Land use change resulted in land degradation is a focus of research on global environmental changes and plays a significant role in the stability and economic development of oases in arid regions of China. Jinta Oasis, a typical oasis of temperate arid zone in northwestern China, was investigated to assess land-use change dynamics during 1988–2003 with the aid of satellite remote sensing and GIS, and to explore the interaction between these changes and oasis environment. Six land-use types were identified, namely: cropland, forestland, grassland, water, urban or built-up land, and barren land. The results indicate that cropland, urban/built-up land, and barren land increase greatly by 30.03, 13.35, and 15.52 km², respectively; but grassland and forestland areas decrease rapidly by 58.06, and 1.76 km², respectively. These results also show that obvious widespread changes in land-use occur within the whole oasis over the study period and result in severe problems of environmental degradation (i.e. land desertification, decline of groundwater, and vegetation degeneracy).     

On the intensity and type transition of land use at the basin scale using RS/GIS: a case study of the Hanjiang River Basin

The purpose of this study is to investigate the land use intensity and land use change type at the basin scale in the middle and lower reaches of the Hanjiang River Basin (in Hubei Province, China) by combining the Landsat TM images in 1995 and 2000 with the land use database (in scale 1:10,000) and relative data. In this study, the basic data is acquired from the interpretation of remote sensing (RS) images. The intensity of land use and the rate of change in double-directions of land use dynamics are calculated with the support of software ARC/INFO. The intensity of land use is indicated by the intensity coefficient of land use, and the transition of land use types is quantified as the rate of change in double-direction of land use types and also expressed as the transition matrix of land use types. The results are expressed in space by Geographic Information System (GIS) software. Results of this study show that (1) the intensity of land use is high in the study region, the intensity coefficients of land use in 1995 and 2000 are 260.025 and 290.526, respectively, and the intensity of development and utilization of land is trend to increscent; and (2) the rate of land use change in double directions in the whole study region is 0.52 with great spatial variation and the differentiation of land use types. In the differentiation of land use types, the unutilized land (with the rate to 4.391) is developed fast, the grassland (with 2.836) and water area (with 1.664) are disturbed severely, and these changes will influence the eco-environment in the Hanjiang River Basin and all the Yangtze Basin. The rates of the farmland and the woodland are 0.424 and 0.344, respectively, meaning that the fundamentals of regional human-environmental system are relative stable. With this study, we can conclude that (1) the patterns of land use are increasingly changing in the study region, the environmental impacts are escalated on this stage, and the further outcomes are destined to change the stability of the regional human–environmental system; and (2) the most useful method to study the present land use and its change is through the use of the RS/GIS with the land use database (in scale 1:10,000).     

Monitoring land use/land cover changes using CORINE land cover data: a case study of Silivri coastal zone in Metropolitan Istanbul

The objective of the present study was to assess changes in land use/land cover patterns in the coastal town of Silivri, a part of greater Istanbul administratively. In the assessment, remotely sensed data, in the form of satellite images, and geographic information systems were used. Types of land use/land cover were designated as the percentage of the total area studied. Results calculated from the satellite data for land cover classification were compared successfully with the database Coordination of Information on the Environment (CORINE). This served as a reference to appraise the reliability of the study presented here. The CORINE Program was established by the European Commission to create a harmonized Geographical Information System on the state of the environment in the European Community. Unplanned urbanization is causing land use changes mainly in developing countries such as Turkey. This situation in Turkey is frequently observed in the city of Istanbul. There are only a few studies of land use–land cover changes which provide an integrated assessment of the biophysical and societal causes and consequences of environmental degradation in Istanbul. The research area comprised greater Silivri Town which is situated by the coast of Marmara Sea, and it is located approximately 60 km west of Istanbul. The city of Istanbul is one of the largest metropolises in Europe with ca. 15 million inhabitants. Additionally, greater Silivri is located near the terminal point of the state highway connecting Istanbul with Europe. Measuring of changes occurring in land use would help control future planning of settlements; hence, it is of importance for the Gretaer Silivri and Silivri Town. Following our evaluations, coastal zone of Silivri was classified into the land use groups of artificial surfaces agricultural areas and forests and seminatural areas with 47.1%, 12.66%, and 22.62%, respectively.     

Spatiotemporal distribution and the characteristics of the air temperature of a river source region of the Qinghai-Tibet Plateau

As the backland of the Qinghai-Tibet Plateau, the river source region is highly sensitive to changes in global climate. Air temperature estimation using remote sensing satellite provides a new way of conducting studies in the field of climate change study. A geographically weighted regression model was applied to estimate synchronic air temperature from 2001 to 2015 using Moderate-Resolution Imaging Spectroradiometry (MODIS) data. The results were R²?=?0.913 and RMSE?=?2.47 °C, which confirmed the feasibility of the estimation. The spatial distribution and variation characteristics of the average annual and seasonal air temperature were analyzed. The findings are as follows: (1) the distribution of average annual air temperature has significant terrain characteristics. The reduction in average annual air temperature along the elevation of the region is 0.19 °C/km, whereas the reduction in the average annual air temperature along the latitude is 0.04 °C/degree. (2) The average annual air temperature increase in the region is 0.37 °C/decade. The average air temperature increase could be arranged in the following decreasing order: Yangtze River Basin > Mekong River Basin > Nujiang River Basin > Yarlung Zangbo River Basin > Yellow River Basin. The fastest, namely, Yangtze River Basin, is 0.47 °C/decade. (3) The average air temperature rise in spring, summer, and winter generally increases with higher altitude. The average annual air temperature in different types of lands following a decreasing order is as follows: wetland > construction land > bare land glacier > shrub grassland > arable land > forest land > water body and that of the fastest one, wetland, is 0.13 °C/year.     

Assessment of big floods in the Eastern Black Sea Basin of Turkey

In this study, general knowledge and some details of the floods in Eastern Black Sea Basin of Turkey are presented. Brief hydro-meteorological analysis of selected nine floods and detailed analysis of the greatest flood are given. In the studied area, 51 big floods have taken place between 1955–2005 years, causing 258 deaths and nearly US $500,000,000 of damage. Most of the floods have occurred in June, July and August. It is concluded that especially for the rainstorms that have caused significantly damages, the return periods of the rainfall heights and resultant flood discharges have gone up to 250 and 500 years, respectively. A general agreement is observed between the return periods of rains and resultant floods. It is concluded that there has been no significant climate change to cause increases in flood harms. The most important human factors to increase the damage are determined as wrong and illegal land use, deforestation and wrong urbanization and settlement, psychological and technical factors. Some structural and non-structural measures to mitigate flood damages are also included in the paper. Structural measures include dykes and flood levees. Main non-structural measures include flood warning system, modification of land use, watershed management and improvement, flood insurance, organization of flood management studies, coordination between related institutions and education of the people and informing of the stakeholders.     

Land Use and Climate Change Impacts on the Hydrology of the Bago River Basin,Myanmar

Assessment of land use and climate change impacts on the hydrological cycle is important for basin scale water resources management. This study aims to investigate the potential impacts of land use and climate change on the hydrology of the Bago River Basin in Myanmar. Two scenarios from the representative concentration pathways (RCPs): RCP4.5 and RCP8.5 recommended by the Intergovernmental Panel on Climate Change, Fifth Assessment Report (IPCC AR5) were used to project the future climate of 2020s, 2050s, and 2080s. Six general circulation models (GCMs) from the Coupled Model Intercomparison Project Phase 5 (CMIP5) were selected to project the future climate in the basin. An increase of average temperature in the range of 0.7 to 1.5 °C and 0.9 to 2.7 °C was observed under RCP 4.5 and RCP 8.5, respectively, in future periods. Similarly, average annual precipitation shows a distinct increase in all three periods with the highest increase in 2050s. A well calibrated and validated Soil and Water Assessment Tool (SWAT) was used to simulate the land use and climate change impacts on future stream flows in the basin. It is observed that the impact of climate change on stream flow is higher than the land use change in the near future. The combined impacts of land use and climate change can increase the annual stream flow up to 68 % in the near future. The findings of this study would be beneficial to improve land and water management decisions and in formulating adaptation strategies to reduce the negative impacts, and harness the positive impacts of land use and climate change in the Bago River Basin.