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Summary: Alpine meadow soil is an important ecosystem component of the Qinghai-Tibetan Plateau. However, the alpine meadow soil is undergoing serious degradation mainly due to global climate change, overgrazing, human activities and rodents. In this paper, spatial sequencing was chosen over time succession sequencing to study the changes of soil hydraulic properties under different degrees of alpine meadow degradation. Soil saturated hydraulic conductivity (Ks) and Gardner α both at the surface and at 40–50cm depth were investigated in the field using tension infiltrometers. Soil physical and chemical properties, together with the root index at 0–10cm and 40–50cm soil layer depths were also analyzed. Pearson correlations were adopted to study the relationships among the investigated factors and principal component analysis was performed to identify the dominant factor. Results show that with increasing degree of degradation, soil sand content increased while soil Ks and Gardner α as well as soil clay content, soil porosity decreased in the 0–10cm soil layers, and organic matter and root gravimetric density decreased in both the 0–10cm and 40–50cm soil layers. However, soil moisture showed no significant changes with increasing degradation. With decreasing pressure head, soil unsaturated hydraulic conductivity reduced more slowly under degraded conditions than non-degraded conditions. Soil Ks and Gardner α were significantly correlated (P =0.01) with bulk density, soil porosity, soil organic matter and root gravimetric density. Among these, soil porosity is the dominant factor explaining about 90% of the variability in total infiltration flow. Under non-degraded conditions, the infiltration flow principally depended on the presence of macropores. With increasing degree of degradation, soil macropores quickly changed to mesopores or micropores. The proportion of total infiltration flow through macropores and mesopores significantly decreased with the most substantial decrease observed for the macropores in the 0–10cm soil layer. The substantial decrease of macropores caused a cut in soil moisture and hydraulic conductivity. This study improves the understanding and prediction of alpine meadow soil and ecosystem changes and provides guidelines for improving water flow modeling under the background of global climate change over the Qinghai-Tibetan Plateau and similar regions. [Copyright &y& Elsevier]

Summary: The effect of future climate scenarios on surface water and groundwater resources has been shown to have a consequent impact on water-dependent ecosystems. A regional-scale analysis of changes in water resources as a result of changing climate was undertaken in south-western Australia; a region with a large number of nationally and internationally recognised water-dependent ecosystems. The paper examines the potential environmental impacts of a substantial reduction in rainfall and an increase in temperature as projected by global climate models (GCMs) on river and groundwater-dependent terrestrial vegetation by 2030. Climate change effects on environmentally significant flow regimes were evaluated by applying the climate projections from 15 GCMs under three global warming ‘scenarios to rainfall–runoff and groundwater models. It was estimated that under a dry future climate scenario, the frequency of river flow rates important for ecological communities is likely to be reduced by up to 2months per year, which is likely to cause a significant level of stress to ecological communities. Additionally, the duration of no-flow periods may increase by more than 120days in some streams. Under a dry future climate scenario, groundwater-dependent vegetation is projected to be at a high risk in over 19% of its current habitat area. Water-dependent ecosystems are also projected to be affected by an increase in groundwater abstraction. The results indicate that the projected impacts of future climate conditions are not likely to be uniform across the region but overall they could cause a continuing threat to water-dependent ecosystems. The implementation of water management plans should place particular emphasis on the ecological water requirements in 6 of the 13 river catchments in south-western Australia and in areas where groundwater abstraction is high. The climate projections and ecological impacts are a continuation of the trends that have taken place in the past three decades. [Copyright &y& Elsevier]

Summary: Rapid land use/-cover change has increasingly transformed the hydrological functioning of tropical Andean ecosystems. The hydrological response to forest cover change strongly depends on the initial state of the ecosystem. Relatively little is known about human-disturbed ecosystems where forest plantations have been established on highly degraded land. In this paper, we analyze the impact of forest change on water and sediment fluxes for a highly degraded Andean catchment. Different pathways of land cover change (1963–2007) are observed in the Jadan catchment, with deforestation taking place in remote uplands and recovery and reforestation in the middle and lower parts where agricultural and bare lands are prevalent. Time series analyses of streamflow and rainfall data (1979/1982–2005/2007) show significant shifts in the distribution of rainfall and flow data. Changes in discharge are not resulting from changes in precipitation, as the direction of change is opposite. The removal of native forest for rangeland or croplands (by −20km2) is likely to have contributed to the increase in total annual water yield, through an increase in annual baseflow by 25mm. The observed changes in peakflow are important as the 1st percentile highest flow rates were 54% lower, while the 1st percentile rainfall amounts increased by 52%. The observed decrease in peakflow cannot be explained by clearcut of native forest, but is likely to be related to reforestation of degraded lands as well as spontaneous recovery of vegetation on remaining grazing lands. Over the same time period, a major decrease in specific sediment yields and suspended sediment loads was observed. Although deforestation in the upper parts led to increased landslide activity, this change is not reflected in an increased sediment yield. Small upland rivers are often nearly completely blocked by landslide material, thereby reducing their potential to transport sediment. In contrast, the reduction in estimated erosion is likely to be caused by the reduction of the degraded areas in areal extent as well as to the (partial) recovery of the vegetation in these areas. [Copyright &y& Elsevier]

Summary: The climate scenarios of the IPCC suggest that adaptation to future climate change will be required. The North Sea Region, a marginal sea of the Atlantic Ocean between Great Britain, Scandinavia, Germany, the Netherlands and Belgium, is particularly affected due to rising sea level and a changing water balance. Water management plays a key role in sustainable management of natural and societal resources. This paper presents a participatory study of community approaches to regional adaptation to climate change. Water management adaptation options to regional climate induced changes until 2050 were developed together with stakeholders for the Wesermarsch County (Northern Germany). Available information on expected regional climate change and a modelling study on hydrological change suggested that adaptation of water management will be required until 2050. A regional stakeholder forum formulated a vision on how the Wesermarsch should look like in 2050. Following the holistic approach of collaborative planning, two stakeholder groups developed an adaptation portfolio on how urban and rural areas could adapt their water management to cope with the expected changes. Since most of the stakeholders do not want the county to undergo significant changes in terms of landscape and land use, they proposed technical measures to enforce flood protection and enhance the performance of the existing water management system. Adaptation in terms of land use change was not proposed although information on comparable examples from similar regions was available. To justify the proposed adaptation options, available information on expected climate change impacts was used selectively. Uncertainty in model projections was partly ignored to legitimate suggesting inflexible (technical) adaptation measures. However, collaborative planning proved to be helpful for a joint adaptation to climate change at the regional scale. Stakeholders as well as scientists took active part in the participatory learning process as required by EU directives. [Copyright &y& Elsevier]

Summary: The effect of future climate scenarios on surface water and groundwater resources has been shown to have a consequent impact on water-dependent ecosystems. A regional-scale analysis of changes in water resources as a result of changing climate was undertaken in south-western Australia; a region with a large number of nationally and internationally recognised water-dependent ecosystems. The paper examines the potential environmental impacts of a substantial reduction in rainfall and an increase in temperature as projected by global climate models (GCMs) on river and groundwater-dependent terrestrial vegetation by 2030. Climate change effects on environmentally significant flow regimes were evaluated by applying the climate projections from 15 GCMs under three global warming ‘scenarios to rainfall–runoff and groundwater models. It was estimated that under a dry future climate scenario, the frequency of river flow rates important for ecological communities is likely to be reduced by up to 2months per year, which is likely to cause a significant level of stress to ecological communities. Additionally, the duration of no-flow periods may increase by more than 120days in some streams. Under a dry future climate scenario, groundwater-dependent vegetation is projected to be at a high risk in over 19% of its current habitat area. Water-dependent ecosystems are also projected to be affected by an increase in groundwater abstraction. The results indicate that the projected impacts of future climate conditions are not likely to be uniform across the region but overall they could cause a continuing threat to water-dependent ecosystems. The implementation of water management plans should place particular emphasis on the ecological water requirements in 6 of the 13 river catchments in south-western Australia and in areas where groundwater abstraction is high. The climate projections and ecological impacts are a continuation of the trends that have taken place in the past three decades. [Copyright &y& Elsevier]

Summary: Healthy phytoplankton communities are the basis of healthy water ecosystems, and form the foundation of many freshwater food webs. Globally many freshwater ecosystems are degraded because of intensive human activities, so water ecosystem restoration is a burning issue worldwide. Selection of key regions for phytoplankton-related restoration is crucial for an effective aquatic eco-restoration. This paper presents a practical method for identification of key regions for phytoplankton-related restoration, using random forests (RFs) method to cluster sites based on dominance, biodiversity, water chemistry and ecological niche. We sampled phytoplankton for species richness and relative abundance and water quality in the Huai River basin (HRB), China to determine the phytoplankton communities’ composition and structure and characterize of their ecological niches. A wider mean niche breadth of a species usually leads to a greater overlap with the niche of other species. Using these data and water quality indices, we identified the key regions for phytoplankton-related river restoration activities. Results indicate that our method for recognition of key regions is effective and practical and its application to the HRB identified the Northern Plain area as the key region for restoration. This area is severely polluted and contributes significantly to the HRB phytoplankton communities. Phytoplankton in this region is highly adaptable to environmental change and therefore will be relatively unharmed by environmental instability induced by restoration measures. During restoration, indices of water temperature, total phosphorus and chemical oxygen demand can be altered with little negative influence on phytoplankton communities, but measures that increase ammonia–nitrogen concentration would be highly detrimental. These results will provide valuable information for policy makers and stakeholders in water ecosystem restoration and sustainable basin management in the HRB. [ABSTRACT FROM AUTHOR]

Summary: The purpose of this paper is to trace the evolution of key water-related laws and management practices in Kansas, from the enactment of the Kansas Water Resources Appropriation Act of 1945 to the present, in order to highlight the state’s efforts to create a more sustainable water future and in hopes that others will benefit from Kansas’ experience. The 1945 Act provides the basic framework of water law (prior appropriation) in Kansas. Progression of groundwater management in the state encompasses local Groundwater Management Districts (GMDs) and their water-management programs, minimum-streamflow and TMDL standards, water-use reporting and water metering programs, use of modified safe-yield policies in some GMDs, the subbasin water-resources-management program, the integrated resource planning/aquifer storage and recovery project of the city of Wichita, the Central Kansas Water Bank, enhanced aquifer subunits management, and various water conservation programs. While these have all contributed to the slowing down of declines in groundwater levels in the High Plains aquifer and in associated ecosystems, they have not yet succeeded in halting those declines. Based on the assumption that the different management approaches have to operate easily within the prevailing water rights and law framework to succeed, a number of steps are suggested here that may help further diminish or reverse the declines of the High Plains aquifer. These include eliminating the “use it or lose it” maxim in the prior-appropriation framework, broadening the definition of “beneficial use,” regulating domestic and other “exempt” wells, encouraging voluntary “sharing the shortage” agreements, and determining to what extent water rights may be regulated in the public interest without a compensable “taking”. Further measures include establishing artificial recharge and/or aquifer storage and recovery projects wherever feasible and determining to what extent water-rights holders might be subjected to reasonable dictates without having the security of their rights altered. [ABSTRACT FROM AUTHOR]

Summary: In recent times, significant areas of the Northeastern Argentine (NEA) have been affected by climatic fluctuations which have caused serious damages in ecosystems and people’s livehoods, both by floods and droughts. This has mainly occurred in the Santa Fe Province, having a great impact on the underlying unconfined aquifer. This paper analyzes the relationships between meteorological variability and water table levels in the context of climate variability and climatic change in the lower Carcarañá river experimental basin (about 4700km2), located in the Santa Fe Province. The goal of the study is to obtain long-term (interannual) predictions of water table levels in the region. The methodology used responds to a hypothetical conception of the temporal series having a signal formed by random components with characteristics of white noise. Singular Spectral Analysis (SSA), among other non-parametric techniques were used to identify fluctuations and trend changes in climatic time-series. These characteristics provide valuable information for the evaluation of climatic evolution and for the detection of variations in this evolution, suggesting a climatic change either by natural mechanisms or by anthropogenic impacts. A positive trend in precipitation is found throughout the studied region with water table levels showing a similar spatial–temporal behavior. The SSA gives significant periodicities between 3 and 8years showing a possible link between El Niño-Southern Oscillation (ENSO) phenomenon and precipitation and water table levels. The periodicities linked with ENSO are always present and the structures of the series are similar for the different studied periods. The results obtained, even if they are experimental constitute a first approximation. In general, they are promising, since the generated basis will enable to face further and more complex stages. [Copyright &y& Elsevier]

Summary: Global change encompasses changes in the characteristics of inter-related climate variables in space and time, and derived changes in terrestrial processes, including human activities that affect the environment. As such, projected global change includes groundwater systems. Here, groundwater is defined as all subsurface water including soil water, deeper vadose zone water, and unconfined and confined aquifer waters. Potential effects of climate change combined with land and water management on surface waters have been studied in some detail. Equivalent studies of groundwater systems have lagged behind these advances, but research and broader interest in projected climate effects on groundwater have been accelerating in recent years. In this paper, we provide an overview and synthesis of the key aspects of subsurface hydrology, including water quantity and quality, related to global change. Adaptation to global change must include prudent management of groundwater as a renewable, but slow-feedback resource in most cases. Groundwater storage is already over-tapped in many regions, yet available subsurface storage may be a key to meeting the combined demands of agriculture, industry, municipal and domestic water supply, and ecosystems during times of shortage. The future intensity and frequency of dry periods combined with warming trends need to be addressed in the context of groundwater resources, even though projections in space and time are fraught with uncertainty. Finally, potential impacts of groundwater on the global climate system are largely unknown. Research to improve our understanding of the joint behaviors of climate and groundwater is needed, and spin-off benefits on each discipline are likely. [Copyright &y& Elsevier]

Summary: Quantifying the effects of groundwater abstraction on fen ecosystems located in discharge areas can be complicated. The water level in fens is close to the terrain surface most of the year and it is controlled by a relatively constant groundwater exfiltration. It is difficult to measure the exfiltration fluxes and thus water level data is typically used to evaluate if the ecosystem is affected. The paper presents collected data and analysis from a case study, where the hydrological effect of groundwater abstraction on rich fens and springs in a Danish river valley has been studied. The natural hydrological conditions have been monitored intensively since March 2007. In the early spring 2009 two full scale pumping test were conducted in the regional high yield limestone aquifer. The evaluation focuses on three isolated fens covering an area of approximately 5000m2 each and two natural springs all within a distance of 1.5km to a planned well field. In the river valley the interaction between groundwater and surface water is strongly affected by low permeable sediments. These sediments reduce the direct discharge to the river and have a large impact on the functioning and presence of the rich fen and spring habitats. Continuous water level data from deep and shallow wells in the fens reflect the hydrological conditions. Large differences in water level drawdown during dry summer periods have been observed in the monitored fens and it is hypothesised, that these differences are directly related to the groundwater seepage rate. Two pumping tests with duration of 3 weeks were performed at two different locations and the effects were monitored with 20 pressure transducers in monitoring wells and by continuous flow logging in springs in the area. A significant reduction of the flow in the springs has been measured while the on the water level in the fens is difficult to distinguish from the natural variations. It is concluded, that hydrological modelling is a necessary tool in order to predict the long term effects of pumping in the fen areas. The collected data gives valuable knowledge on the hydrology of the monitored ecosystems and the response towards groundwater abstraction and forms a solid foundation for hydrological modelling. [Copyright &y& Elsevier]

Summary: Reliability of traditional methodologies is often challenged in determination of instream ecological flow (IEF) for a regulated river due to its non-natural condition. This paper deals with an IEF determination method for regulated rivers called the Adapted Ecological Hydraulic Radius Approach (AEHRA). It considers information of both instream ecosystem and river course, while it does not require any flow regime. Beside monthly IEF, it outputs monthly Instream Ecological Water-level (IEW) as well. The latter can greatly facilitate dam operation. Application of this method to the Huai River which is completely regulated by dams suggest: (1) AEHRA is especially predictive for rivers with limited ecological and hydrological data; (2) it can reflect the seasonal variation of IEF and IEW; (3) errors of AEHRA introduced by using a geometric shape generalized cross-section in an un-gauged site are generally acceptable; (4) comparison of the IEF values estimated by AEHRA with those by Tennant approach, Wetted Perimeter method and R2CROSS method showed fairly good agreement in terms of practical capability of the AEHRA. This method will be of great help for regionally sustainable water management in data-scarce regulated rivers [ABSTRACT FROM AUTHOR]

Summary: Protection of surface- and ground-water quality is critical for economic viability, as well as for human health and the environment. Furthermore, maintenance of the biodiversity of natural aquatic ecosystems is very important. The objective of this paper is to report methodology developed for the assessment of the surface-water exposure to pesticide using as example the fungicide quinoxyfen because persistent, lipophylic and hazard for the aquatic organisms. Exposure monitoring was carried out over two years (2005 and 2006) following historical and subsequent applications in Italian vineyards and to investigate the presence of residue in non-target areas close to the crop receiving repeated applications. After development of the monitoring procedures, surface-water contamination and biota exposure were determined during and after field treatments. Very low concentrations were found in sediments, often in contradiction with model and laboratory results, leading to the conclusion that even the historical use of quinoxyfen in vineyards within the catchment was not contaminating sediment in water bodies, which was regarded as the natural sink for such a pesticide due to its strong sorptive properties. For biota, quinoxyfen residues in benthic macroinvertebrates and fish in the vast majority of the samples were below the corresponding limit of detection (LOD). Thus long-term accumulation of quinoxyfen in sediments and organisms of the aquatic ecosystems would not be expected due main to the environmental conditions of the landscape that mitigate the overall exposure. [Copyright &y& Elsevier]

Summary: Land-use and forest cover change play important roles in socio-economic processes and have been linked with water supply and other ecosystem services in various regions of the world. Water yield from watersheds is a major ecosystem service for human activities but has been dramatically altered by landscape management superimposed on climatic variability and change. Many studies from different regions of the world have documented that in small watersheds (<100ha) fast-growing forest plantations reduce water yield. Nevertheless, these effects have not been adequately documented in large watersheds >10,000ha. In this paper, we examine the temporal variation of the residuals between best-fit precipitation–runoff relationships and instrumental streamflow records for two large watersheds (Purapel en Nirivilo, PNN and Cauquenes en el Arrayán, CQA) located in the Mediterranean-climate coastal range of South-Central Chile. In these watersheds, high resolution satellite imagery shows a decline in native forest cover from 52.3% to 14.2% for PPN and 36.1% to 8.1% in CQA, between 1975 and 2000. Conversely, in the same period the percentage area covered by forest plantations, mainly Pinus radiata, increased from 12% to 55% in PPN, and 4.7% to 42% in CQA. We observed a decreasing trend in summer runoff residuals regressed against annual precipitation in the same period, with slopes significantly different from zero for PPN (p =0.035) and CQA (p =0.008). We interpreted this pattern as an evidence of change in the hydrological regime in these watersheds as a consequence of forest cover and land-use changes. From a reanalysis of the observed data we estimate a decrease in runoff from 13.1 to 7.5mm/summer for PPN and from 7.3 to 5mm/summer for CQA, refer to the period 1991–2000 compared to 1981–1990. Multiple regression analyses of annual and seasonal flows show that besides precipitation, percentage-cover of forest plantations is a statistically significant predictor of summer flow with a partial negative correlation of −0.45 and −0.44 for PPN and CQA, respectively, p < 0.05. This study clearly shows the important effect that land-use change can have on water yield and to our knowledge this is the first study documenting the decrease in summer runoff in a landscape where native forest cover has dramatically declined and forest exotic plantations have expanded. Similar methods could be used elsewhere to inform policy and decision-making regarding forest and land-use planning. [Copyright &y& Elsevier]