Environmental Challenges and Impacts of Land-Use Conversion in the Yellow River Basin

While the Chinese population continues to grow, Chinese policy makers are faced with a seemingly insurmountable task of satisfying demands for fresh water, electricity, agricultural products, etc. Not only is the irrigated land area presently shrinking, as previously cultivated is converted to various non-agricultural purposes, but additionally, advancing pollution from expanding mining industries, urban centers, and upstream input-intensive farmlands, are causing a reduction in the usability of the Yellow River water. Unfavorable climatic, topographic, and geomorphic preconditions further constrain food production potentials. The exceptionally high silt load and sedimentation rate in the Yellow River constitute another major challenge for engineers. Dam construction and maintenance work are aggravated by rapid sedimentation in reservoirs, undermining potentials for water supply storage and electricity production. Likewise, flood prevention measures in the Lower Reaches are counteracted by sediment build-up in the canal. In the entire basin, freshwater constitutes an advancing challenge, with regard to its usability, storage, allocation, and absolute seasonal availability. Based on a review of potential river ecological impacts of irrigation and multi-purpose dams, this report concludes that advancing intensification of agricultural practices and continuous construction of large dams may significantly alter riverine ecosystems with adverse implications for human livelihoods. The author argues that any larger intervention in the riverine landscape should by necessity be preceded by a comprehensive assessment of the river's various functions and values for its different user groups. Such an assessment should consider not only the physical, but also the water quality and biological aspects and their interrelations. Just as many scientists tend to focus only on a few research parameters, managerial strategies often tend to target only one or a few objectives at a time. Balancing the different interests at hand, based on a comprehensive but understandable environmental impact assessment, is identified as the key to successful integrated river basin management

A baseline appraisal of water-dependant ecosystem services, the roles they play within desakota livelihood systems and their potential sensitivity to climate change

This report forms part of a larger research programme on 'Reinterpreting the Urban-Rural Continuum', which conceptualises and investigates current knowledge and research gaps concerning 'the role that ecosystems services play in the livelihoods of the poor in regions undergoing rapid change'. The report aims to conduct a baseline appraisal of water-dependant ecosystem services, the roles they play within desakota livelihood systems and their potential sensitivity to climate change. The appraisal is conducted at three spatial scales: global, regional (four consortia areas), and meso scale (case studies within the four regions). At all three scales of analysis water resources form the interweaving theme because water provides a vital provisioning service for people, supports all other ecosystem processes and because water resources are forecast to be severely affected under climate change scenarios. This report, combined with an Endnote library of over 1100 scientific papers, provides an annotated bibliography of water-dependant ecosystem services, the roles they play within desakota livelihood systems and their potential sensitivity to climate change. After an introductory, section, Section 2 of the report defines water-related ecosystem services and how these are affected by human activities. Current knowledge and research gaps are then explored in relation to global scale climate and related hydrological changes (e.g. floods, droughts, flow regimes) (section 3). The report then discusses the impacts of climate changes on the ESPA regions, emphasising potential responses of biomes to the combined effects of climate change and human activities (particularly land use and management), and how these effects coupled with water store and flow regime manipulation by humans may affect the functioning of catchments and their ecosystem services (section 4). Finally, at the meso-scale, case studies are presented from within the ESPA regions to illustrate the close coupling of human activities and catchment performance in the context of environmental change (section 5). At the end of each section, research needs are identified and justified. These research needs are then amalgamated in section 6

Using Remote Sensing Techniques to Improve Hydrological Predictions in a Rapidly Changing World

Remotely sensed geophysical datasets are being produced at increasingly fast rates to monitor various aspects of the Earth system in a rapidly changing world. The efficient and innovative use of these datasets to understand hydrological processes in various climatic and vegetation regimes under anthropogenic impacts has become an important challenge, but with a wide range of research opportunities. The ten contributions in this Special Issue have addressed the following four research topics: (1) Evapotranspiration estimation; (2) rainfall monitoring and prediction; (3) flood simulations and predictions; and (4) monitoring of ecohydrological processes using remote sensing techniques. Moreover, the authors have provided broader discussions on how to capitalize on state-of-the-art remote sensing techniques to improve hydrological model simulations and predictions, to enhance their skills in reproducing processes for the fast-changing world

Assessing the integrated water resources development potential of Wadi systems in Iran and their vulnerability to climate change

Similar to other Middle Eastern countries, Iran is experiencing a serious water crisis. Water resources become increasingly stressed in the Wadi regions of central and eastern Iran. Assessing water resources there is thus essential due to growing water demand and possible effects of future climate change. Due to the lack of readily available surface water resources, different water use systems (WUSs) exist that provide water mainly for drinking, irrigation and further domestic use. In addition, many soil and water conservation measures (SWCMs) have been established to slow down the velocity of water and to increase infiltration and percolation rates. These alter hydrological components in Wadi regions that need to be considered. Such characteristics particularly apply to the Wadi basin Halilrood in central Iran. Halilrood River is the largest river in terms of discharge in the Kerman Province and the major water provider for the downstream Jazmorian wetland. The Soil and Water Assessment Tool (SWAT) is employed to model the hydrological processes of the Wadi. WUSs and SWCMs are implemented into the hydrological model to simulate streamflow and major hydrological components under current and future climate change conditions. Moreover, groundwater sustainability and possible alterations in the ecological flow regime are evaluated by taking both climate change and population growth into account. Results of the SWAT model simulation show that the hydrological processes of the Wadi system are better represented when WUSs and SWCMs are implemented. The improvement in model performance varies for different segments of the hydrograph. Peak and mean flows are simulated more accurately due to the improved depiction of infiltration rates and the slower release of water to the channels. The investigation of hydrological components reveals that the contribution of surface runoff and groundwater flows to the streams decrease in all sub-basins with WUSs. On the contrary, a higher contribution of groundwater to the streams is shown in most sub-basins with SWCMs. In sub-basins with both WUSs and SWCMs, groundwater contribution increases or does not show any change. To assess the impact of climate change on the water resources in the near and far future (2030-2059 and 2070-2099) in comparison to the baseline period (1979-2009), the projections from 11 climate models and two bias correction methods (LS: linear scaling and DM: distribution mapping) for two Representative Concentration Pathways (RCP4.5 and RCP8.5) are used as input data for the calibrated hydrologic model. The results indicate a slight increase of streamflow in winter season for both RCPs and both bias correction methods, due to higher precipitation intensity. Besides that, a shift is simulated in the timing of the seasonal peak-flow. This is due to increases in temperature and changes in the precipitation pattern. The Halilrood Basin is expected to be vulnerable to climate change as different segments of the flow duration curve (FDC) show increasing variability that can also be interpreted as an alteration of the future flood and drought extremes. A decrease for very high and high flows is projected under both RCPs. Climate change is causing a slight increase in evaporation and less available water for infiltration and percolation, which eventually leads to zero contribution of groundwater to the main channel. The impacts of climate change and growing water demand on the sustainability of groundwater use and the hydrologic regime of the Wadi are analyzed by linking the SWAT model results to the Indicators of Hydrologic Alteration (IHA) and the Range of Variability Approach (RVA). An unsustainable water resources situation (groundwater recharge is equal or greater than groundwater Demand) is expected in the future for the vast majority of sub-basins with WUSs. Due to the imbalance between the groundwater recharge under climate change and estimated groundwater demand in the future, a decline of groundwater levels is anticipated for the entire Halilrood Basin. This is not only resulting in unsustainable groundwater use, but also changes the hydrologic regime and poses a significant threat to downstream ecosystems. The presented modeling framework is a useful approach, providing beneficial information on the water resources of Iranian Wadi systems and their vulnerability to climate change and population growth. The results of this research can contribute to long-term planning there, which is required for a sustainable water resources management under changing future conditions

The Waters of The Third Pole: Sources of Threat, Sources of Survival

The purpose of this report is to open up a dialogue on an issue that could put the lives and livelihoods of millions of people at risk in the foreseeable future. This issue is water – water as a vital resource and as a potential crisis driver in the Hindu-Kush Himalaya (HKH) region. In seeking to foster that dialogue, the report has three specific objectives: [i] to survey various types of potential water-related hazards and crisis drivers that could affect the region; [ii] to foster new types of alliances – including greater attention to what will be called humanitarian policy-maker/ science dialogues – for addressing the threats that the region may face; and [iii] to propose first steps that must be taken now to lead to prevention and preparedness measures commensurate with the nature and scale of threats facing the region

Water Resource Variability and Climate Change

Climate change affects global and regional water cycling, as well as surficial and subsurface water availability. These changes have increased the vulnerabilities of ecosystems and of human society. Understanding how climate change has affected water resource variability in the past and how climate change is leading to rapid changes in contemporary systems is of critical importance for sustainable development in different parts of the world. This Special Issue focuses on “Water Resource Variability and Climate Change” and aims to present a collection of articles addressing various aspects of water resource variability as well as how such variabilities are affected by changing climates. Potential topics include the reconstruction of historic moisture fluctuations, based on various proxies (such as tree rings, sediment cores, and landform features), the empirical monitoring of water variability based on field survey and remote sensing techniques, and the projection of future water cycling using numerical model simulations

Sustainable Use of Soils and Water: The Role of Environmental Land Use Conflicts

This book on the sustainable use of soils and water addressed a variety of issues related to the utopian desire for environmental sustainability and the deviations from this scene observed in the real world. Competing interests for land are frequently a factor in land degradation, especially where the adopted land uses do not conform with the land capability (the natural use of soil). The concerns of researchers about these matters are presented in the articles comprising this Special Issue book. Various approaches were used to assess the (im)balance between economic profit and environmental conservation in various regions, in addition to potential routes to bring landscapes back to a sustainable status being disclosed

Vegetation Dynamics Revealed by Remote Sensing and Its Feedback to Regional and Global Climate

This book focuses on some significant progress in vegetation dynamics and their response to climate change revealed by remote sensing data. The development of satellite remote sensing and its derived products offer fantastic opportunities to investigate vegetation changes and their feedback to regional and global climate systems. Special attention is given in the book to vegetation changes and their drivers, the effects of extreme climate events on vegetation, land surface albedo associated with vegetation changes, plant fingerprints, and vegetation dynamics in climate modeling

Sustainability in China: Bridging Global Knowledge with Local Action

China’s road to sustainability has attracted global attention. Since the “Reform & Opening Up” policy, China’s rapid pace of both urbanization and industrialization has made its being the second largest economy but meantime a heavy environmental price has been paid over the past few decades for addressing the economic developmental target. Today, as the biggest developing country, China needs to take more responsibilities for constructing its local ecological-civilization society as well as for addressing the global challenges such as climate change, resources scary and human beings well-fare; therefore, we need to have deeper understandings into China’s way to sustainability at very different levels, both spatially and structurally, concerns ranging from generating sustainable household livelihoods to global climate change, from developing technological applications to generate institutional changes. In this spirit, this publication, “Sustainability in China: Bridging Global Knowledge with Local Action” aims to investigate the intended and spontaneous issues concerning China’s road to sustainability in a combined top-down and bottom-up manner, linking international knowledge to local-based studies

Remote sensing based evaluation of uncertainties on modelling of streamflow affected by climate change

Assessment of the impacts of land-use and climate change on streamflow is vital to develop climate adaptation strategies. However, uncertainties in the climate impact study framework could lead to changes on streamflow impact. The aim of this study is to assess the uncertainties on Digital Elevation Model (DEM), Satellite Precipitation Product (SPP) and climate projection on the modelling of streamflow affected by climate changes. These uncertainties are evaluated and reduced independently. The climate projection uncertainty is addressed through the modification of the Quantifying and Understanding the Earth System - Global Scale Impacts (QUEST-GSI) methodology. Twenty-six modified QUEST-GSI climate scenarios were used as climate inputs into the calibrated Soil and Water Assessment Tool (SWAT) model to evaluate the impacts and uncertainties of climate change on streamflow for three future periods (2015-2034, 2045-2064 and 2075-2094). The selected study areas are the Johor River Basin (JRB) and Kelantan River Basin (KRB), Malaysia. The Shuttle Radar Topography Mission (SRTM) version 4.1 (90m resolution) DEM and the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks – Climate Data Record (PERSIANN-CDR) SPP which show a better performance were selected for the SWAT model modification, calibration and validation. The results indicated that the modified SWAT model could simulate the monthly streamflow well for both basins. Land-use and climate changes from 1985 to 2012 reduced annual streamflow of the JRB and KRB by 5% and 4.2%, respectively. In future, the annual precipitation and temperature of the JRB / KRB are projected to increase by -0.4-10.3% / 0.1-11.2% and 0.6-3.2oC / 0.8-3.3oC, respectively, and that this will lead to an increase of annual streamflow by 0.5-13.3% / 4.4-18.5%. This study showed that satellite data play an important role in providing input data to hydrological models