Let’s bring in the floods: de-poldering in the Netherlands as a strategy for long-term delta survival?

Controlled flooding, while heavily contested, is being experimented with in the Dutch delta as a new and ecologically oriented strategy to deal with floods, in contrast to the conventional flood prevention paradigm. The Noordwaard project (2012–15) represents an exemplary case. At the expense of agricultural practices, land is set aside occasionally to accommodate river floods, while restored flood and tidal dynamics aim to benefit nature development. It is argued that although controlled flooding aims to restore historical land and water dynamics in the area, the role of sedimentation processes has remained largely unaddressed in relation to shaping long-term delta futures.     

Buried bedrock valleys revealed in Michigan’s central Upper Peninsula using the horizontal-to-vertical spectral ratio passive seismic method

A network of north–south linear troughs occupies the eastern portion of the Lake Superior basin. Morphology suggests these features are tunnel valleys that formed through erosion as subglacial conduits and conveyed meltwater to a former glacial margin. We demonstrate the southern continuation of these valleys onshore into the central Upper Peninsula of Michigan by mapping bedrock topography using the Horizontal-to-Vertical Spectral Ratio (HVSR) passive seismic method. This is a single location, noninvasive seismic technique that records ambient signal. HVSR data are used to estimate subsurface elevation of the sediment-bedrock contact at each site. Regional bedrock topography was estimated using HVSR data from 347 locations. We delineated, for the first time, eight buried (or partially buried) bedrock valleys with geometric characteristics (width, depth, orientation, and continuity) suggesting a southward extension of the Lake Superior tunnel valley network. The largest valleys terminate near the crest of the Munising/Grand Marais upland. This association suggests the upland was constructed by deposition of sediment-laden meltwater at the terminal ends of these tunnel valleys as fans (or heads of outwash). Episodic erosion of the largest valleys likely began during the Two Rivers phase (～13 ka) and were again active during the Marquette phase (～11 ka). The smallest valleys developed later during final regional deglaciation following the Marquette phase.     

Contemporary legal analysis of China’s transboundary water regimes: international law in practice

China’s rapid development places growing pressure on its water resources, including its considerable transboundary waters. This paper analyses the current situation of China’s transboundary water regimes through a legal analytical framework. The evaluation of treaty and state practice reveals that while China adheres to and follows some fundamental rules of international water law, gaps remain. New trends in China’s state practice and in the field of international law offer interesting opportunities for addressing these shortcomings.     

Unpacking water conflicts: a reinterpretation of coordination problems in China’s water-governance system

In China, water conflicts have been traditionally framed as the external costs of economic development and tackled with technocratic measures. This study examines water conflicts through the lens of water diversion, water allocation and water functional zoning. It reframes water conflicts as a result of coordination problems nested in complex inter-jurisdictional interactions. With a game-theoretic illustration, it identifies that individual and group heterogeneities are two challenges to effective coordination. It argues that China’s state-centric water institutions are tailored to optimize overall social utilities, yet they constrain coordination due to insufficient costs and benefits redistribution mechanisms at the local level.     

Telecoupling in urban water systems: an examination of Beijing’s imported water supply

Urban centres increasingly have difficulties meeting water needs within their hydrologic basins. To sustain urban water supply, cities and water source regions have increased telecouplings (socio-economic and environmental interactions over distances). To analyse these complex interactions, we apply the new telecoupling framework to the water-stressed megacity of Beijing’s imported water supply. We found that Beijing’s remote water sources have lower risk than local supply, but connections impact the sending systems. The telecoupling framework provides a standard, systematic and flexible tool for evaluating the sustainability of urban water supply. It also identifies a number of research gaps for future quantification efforts.     

Budyko’s Based Method for Annual Runoff Characterization across Different Climatic Areas: an Application to United States

Runoff data knowledge is of fundamental importance for a wide range of hydrological, ecological, and socioeconomic applications. The reconstruction of annual runoff is a fundamental task for several activities related to water resources management, especially for ungauged basins. At catchment scales, the Budyko’s framework provides an extremely useful and, in some cases, accurate estimation of the long-term partitioning of precipitation into evapotranspiration and runoff as a function of the prevailing climatic conditions. Recently the same long-term partitioning rules have been successfully used to describe water partitioning also at the annual scale and calculate the annual runoff distribution within a simple analytic framework in arid and semi-arid basins. One of the main advantages of the latter method is that only annual precipitation and potential evapotranspiration statistics, and the Fu’s equation parameter ω are required to obtain the annual runoff probability distribution. The aim of this study is to test the limit and potentialities of the aforementioned method under different climatic conditions. To this aim, the model is applied to more than four hundred basins located in the United States. Catchments were grouped into five different samples, following the subdivision of the continental region in five homogeneous climatic zones according to Köppen-Geiger classification. The theoretical probability distribution of annual runoff at each basin has been compared with that derived from historical observations. The results confirm the capability of the tested technique to reproduce the empirical annual runoff distributions with similar and satisfactory performances across different areas, revealing a good option also in cases characterized by climate and hydrological conditions very different from those hypothesized during the original analytical model design, thus extending the geographical and conceptual limits of applicability of the framework.     

Development of China’s Coal-Fired Power Plants in the Coming Years

Power Technology and Engineering - Among the measures aimed at reducing emissions of technogenic “greenhouse gases” (primarily CO2), China plans to halve the total installed capacity of...     

Scientists’ Warning to Humanity: Rapid degradation of the world’s large lakes

Large lakes of the world are habitats for diverse species, including endemic taxa, and are valuable resources that provide humanity with many ecosystem services. They are also sentinels of global and local change, and recent studies in limnology and paleolimnology have demonstrated disturbing evidence of their collective degradation in terms of depletion of resources (water and food), rapid warming and loss of ice, destruction of habitats and ecosystems, loss of species, and accelerating pollution. Large lakes are particularly exposed to anthropogenic and climatic stressors. The Second Warning to Humanity provides a framework to assess the dangers now threatening the world’s large lake ecosystems and to evaluate pathways of sustainable development that are more respectful of their ongoing provision of services. Here we review current and emerging threats to the large lakes of the world, including iconic examples of lake management failures and successes, from which we identify priorities and approaches for future conservation efforts. The review underscores the extent of lake resource degradation, which is a result of cumulative perturbation through time by long-term human impacts combined with other emerging stressors. Decades of degradation of large lakes have resulted in major challenges for restoration and management and a legacy of ecological and economic costs for future generations. Large lakes will require more intense conservation efforts in a warmer, increasingly populated world to achieve sustainable, high-quality waters. This Warning to Humanity is also an opportunity to highlight the value of a long-term lake observatory network to monitor and report on environmental changes in large lake ecosystems.     

Financial performance of India’s irrigation sector: a historical analysis

Abstract

India’s public irrigation sector is one of the largest in the world in terms of number of large reservoirs, total storage capacity and irrigated area. But poor financial performance has been threatening its sustainability. Hence, many changes have been introduced in the area of water pricing over the years. But studies that focus on the issue of financial recovery are scanty. Analysis presented in the article shows that despite a substantial increase in area under irrigation, there has been a consistent decline in revenue generated from irrigation fee collection across states. The recovery rate of irrigation fees has been better in less developed states than in more developed states.     

District Metered Areas Design Under Different Decision Makers’ Options: Cost Analysis

Water loss is a big challenge for water supply companies worldwide, and the Water Network Partitioning (WNP) is an excellent tool for water loss management–particularly in the current difficult economic and financial conditions. WNP is a recent research line and consists in dividing the water distribution network into smaller zones called District Metered Areas (DMAs) with one (or more, in exceptional cases) supply point, to reduce the network complexity and/or allow pressure management. Since there are several possible future scenarios, such as the water demand and/or the infrastructure degradation forecasts, which may have different impacts on the hydraulic behaviour, in this paper a computational application, based on an optimization model, is proposed to achieve a compromise between robustness required for the DMAs design (using a baseline scenario) and different decision makers’ options (using other scenarios with a lower “probability” of occurrence), to reduce the total cost. The objective function reflects the minimization of the squared deviations between the total cost of the DMAs design and the minimum cost for each scenario forecasted for the project plan, multiplied by the weight or “probability” of occurrence for each of the scenarios. The performance of the computational application is illustrated with a case study, and the results are encouraging.     

The interplay of activists and dam developers: the case of Myanmar’s mega-dams

Scholars investigating activism against large dam developments in Asia usually focus on those campaigning, but not on those the campaigns are aimed at – the dam developers. Yet the developers’ perspective is crucial to comprehensively understand the dynamics of social and environmental activism in South-East Asia as well as its implications for the region’s energy landscape. This article analyzes the interplay of activists and Chinese dam developers in Myanmar via case studies of the Myitsone Dam and the Mong Ton Dam. The research is based on direct scholarly interaction with both activists and dam developers. It presents evidence of change from both sides: activists have professionalized in recent years; and Chinese dam developers now attempt to engage with civil society, albeit with limited success in the two cases studied. Yet, even with these changes, conflict over dam development persists, and the country may soon face severe limitations on development options for improving energy security. The case of Bhutan is also discussed to illustrate the potential of developing Myanmar’s hydropower resources.     

Landscape-scale modeling of water quality in Lake Superior and Lake Michigan watersheds: How useful are forest-based indicators?

The Great Lakes watersheds have an important influence on the water quality of the nearshore environment, therefore, watershed characteristics can be used to predict what will be observed in the streams. We used novel landscape information describing the forest cover change, along with forest census data and established land cover data to predict total phosphorus and turbidity in Great Lakes streams. In Lake Superior, we modeled increased phosphorus as a function of the increase in the proportion of persisting forest, forest disturbed during 2000–2009, and agricultural land, and we modeled increased turbidity as a function of the increase in the proportion of persisting forest, forest disturbed during 2000–2009, agricultural land, and urban land. In Lake Michigan, we modeled increased phosphorus as a function of ecoregion, decrease in the proportion of forest disturbed during 1984–1999 and watershed storage, and increase in the proportion of urban land, and we modeled increased turbidity as a function of ecoregion, increase in the proportion of forest disturbed during 2000–2009, and decrease in the proportion softwood forest. We used these relationships to identify priority areas for restoration in the Lake Superior basin in the southwestern watersheds, and in west central and southwest watersheds of the Lake Michigan basin. We then used the models to estimate water quality in watersheds without observed instream data to prioritize those areas for management. Prioritizing watersheds will aid effective management of the Great Lakes watershed and result in efficient use of restoration funds, which will lead to improved nearshore water quality.     

‘Hotel Middle East’: social shocks and adaptation in Jordan’s domestic water sector

While socio-ecological systems are susceptible to social shocks, a theoretical and empirical understanding of social-shock adaptation remains absent from the literature. This article investigates the Syrian refugee crisis in water-scarce Jordan, where historical waves of migration have shaped water governance. Findings suggest that water sector adaptation to social shocks fits within broader adaptation theory, and that frequent refugee crises in Jordan have perpetuated reactive water governance, shaping the sector’s resiliencies, vulnerabilities, and adaptation processes. Through examining adaptation processes in the acute water and refugee contexts of Jordan, we suggest that through planning and preparedness, socio-ecological systems could build resilience to social shocks.     

Patterns of long-term dynamics of aquatic communities and water quality parameters in the Great Lakes: Are they synchronized?

Long time series data can provide insights into dynamics of large lakes. We use the USEPA-GLNPO biological monitoring dataset (phytoplankton, benthos, zooplankton and water quality), collected from 1996 through 2016, to identify whether there is evidence of concordant linear or non-linear trends in community composition, density/biomass/biovolume and major environmental parameters. We show changes in biotic assemblages and water quality variables, particularly in Lakes Michigan and Huron. These include changes in phytoplankton biovolume and zooplankton biomass, increasing invasive Dreissena abundance and decreasing densities of other benthos. Biotic changes are accompanied by pronounced changes in water quality and nutrient ratios. Species change-points, identified using threshold indicator taxon analysis, are often less abrupt, but there are clear shifts in a large proportion of species in each assemblage. The concordance of breakpoints among assemblages or lack thereof provides valuable insight into potential drivers of ecosystem change.     

Trend Analysis in Reference Evapotranspiration Using Mann-Kendall and Spearman’s Rho Tests in Arid Regions of Iran

In this research, temporal trends of reference evapotranspiration (ET0) values were investigated in arid regions of Iran. For this purpose, meteorological observations collected from 11 high quality meteorological sites over a 41-year period (1965–2005) were used and statistically significant ET0 trends in the monthly, seasonal and annual time basis were detected using nonparametric Mann-Kendall (MK) and Spearman’s Rho (SR) tests at the 5% significant level. To eliminate the effect of serial correlation on the test results, the Trend Free Pre-Whitening (TFPW) approach was applied. The results of this study indicated that the ET0 trends for some cities were increasing (positive) however, for some sites, they showed decreasing (negative) trends. The most number of significant ET0 trends on a monthly time scale occurred at Birjand but no significant trend was observed at the Bandarabbas, Sabzevar and Semnan sites. On the annual time scale, Mashhad revealed the highest positive trend (7.5 mm per year). On the other hand, Esfahan showed the highest decreasing (negative) ET0 trend of about −6.38 mm per year. In general, the performances and abilities of the MK and SR tests were consistent at the verified significant level.     

The Compensation Mechanism and Water Quality Impacts of Agriculture-Urban Water Transfers: A Case Study in China’s Chaobai Watershed

Water transfer from agriculture to urban uses will likely become increasingly common worldwide. The objectives of this study were to evaluate the effects of converting paddy rice to dry land crops (PPRDC) on local farmers’ income in China’s Chaobai watershed and to analyze the responses of surface water quality to the change in cropping system. An on-site investigation of 485 households and water quality data from 1999 to 2008 are presented in this study. The cost of cultivation as a percentage of the total revenue was 22.3 % for rice and 30.1 % for corn, and the calculated compensation level (CCOM) should be 6172.3 Yuan?ha^?1. PPRDC provided farms with stable income without regard to drought and flood: thus, farmers responded positively to PPRDC, and 76.7 % of farmers expected to continue PPRDC. Inflow water quality was improved in terms of total nitrogen (TN) and nitrate (NO₃–N) because of the reduction in fertilizer and pesticides after PPRDC, but there was no significant change in total phosphorus (TP). PPRDC not only reallocates water resource to different users but also improves water quality through crop adjustment. A dynamic compensation mechanism based on changing crop price is required for the future water transfer project.     

Impoundment Effects of the Three-Gorges-Dam on Flow Regimes in Two China’s Largest Freshwater Lakes

The impoundment of the Three-Gorges-Dam (TGD) significantly alters the flow regimes in Poyang and Dongting Lakes, the two largest freshwater lakes in China by reducing river discharge. This work aims to investigate the impoundment effects of the TGD on lake outflow and water level and clarify dynamic mechanism for the hydrological responses of both lakes to the TGD impoundment based on the typical case study. A hydrodynamic model is set up to simultaneously simulate hydrodynamics in the two lakes and the middle Yangtze River. Results show that TGD induces profound changes of the flow regimes in both lakes. The effects dynamically change with the TGD-induced Yangtze River discharge alteration, and are highly heterogeneous in space due to the complicated interactions between the lakes and the Yangtze River. The impoundment of the TGD accelerates Poyang Lake drainage. But that is not all for Dongting Lake, the TGD impoundment also reduces its water supply from the Yangtze River. The results from this work improve the understanding of the TGD impacts on the downstream river-lake system and provide scientific evidences for formulating better scheme for water resources management in this region.     

Manning’s ‘n’ co-efficient for flexible emergent vegetation in tandem configuration

A comprehensive laboratory study on the hydraulic resistance characteristics due to a group of slender cylindrical members representing flexible plantation has been carried out in a laboratory open channel. The model stem group comprised of individual members arranged in a tandem configuration. The tests with model vegetation were carried out by adopting different sizes for the individual stems and concentrations which were chosen in such a way that they would fall into practical ranges of vegetations in coastal forestry. The results indicate that the flow resistance varies with stem concentration, stem diameter and elastic properties of the individual members and the flow velocity. Based on the flume data, the Manning’s n, for various flow conditions as well as for vegetative parameters was determined. A new empirical equation is proposed for evaluating the Manning’s n friction coefficient for partially submerged flow when, the depth of flow is greater than 0.8 times the un-deflected plant height. It is expected that the Manning’s n thus determined will be useful in modelling shallow flows using shallow water equations.     

Advancing Africa’s Great Lakes research and academic potential: Answering the call for harmonized,long-term,collaborative networks and partnerships

The African Great Lakes (AGL) have rich fisheries and are renowned “biodiversity hotspots”. Consequently the AGL and the ecosystem services they provide, underpin the welfare and livelihoods of over 50 million people across 10 countries. Despite the recognized importance of the AGL, these vital ecosystems and their livelihood support systems are threatened by numerous anthropogenic stressors at local, regional, and global scales. Past and continued efforts to address critical challenges on these lakes are often short-term, parochial, disparate, and uncoordinated resulting in a lack of comprehensive and comparable scientific data and inadequate resources to influence evidence-based policy. Over the past two decades, several international workshops, conferences and scientific publications have identified the need for collaboration, knowledge sharing, and harmonization of research and management as key elements to enhance conservation efforts in the AGL. In this commentary, we introduce the African Center for Aquatic Research and Education (ACARE), which aims to strengthen research and provide the scientific evidence needed to make informed decisions related to sustainable fisheries and aquatic resource management in the AGL. To do this, ACARE will administer a highly collaborative network of experts with three long-term goals: (1) strengthen global and regional research partnerships; (2) establish transboundary and inter-jurisdictional lake advisory groups; and (3) build capacity of freshwater scientists through experiential education and public engagement.