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Farmers in the Langhorne Creek–Angas Bremer basin irrigation district of South Australia have faced a series of hydrosocial crises relating to drought and groundwater depletion and degradation. The crises have been negotiated through concerted community engagement and cooperation. Adaptation responses have included a combination of infrastructural development and changes to the licensing, regulation, and oversight of irrigation governance, easing extraction pressures on the local groundwater catchment. However, new risks have emerged in the wake of, and as a result of, these solutions. One aspect of the solution has been to connect the Angas Bremer basin district more intimately to the much larger continental riverine system, the Murray-Darling basin, which stretches across multiple regional and state jurisdictions. The very success of that scalar response to hydrological risk generates broader systemic risks: to water supply and quality from climate change and upstream extraction; to basin governance; and to community cohesion, engagement, flexibility, and resilience. In a post-crisis period, there is a need to understand the emergent risks from transformational adaptation and guard against complacency to ensure that the hydrosocial qualities of flexibility and resilience that enabled positive responses to the initial crises endure to respond to future crises in water supply and its management. [ABSTRACT FROM AUTHOR]

Effective management of large basins necessitates pinpointing the spatial and temporal drivers of primary index exceedances and urban risk factors, offering crucial insights for basin administrators. Yet, comprehensive examinations of multiple pollutants within the Yangtze River Basin remain scarce. Here we introduce a pollution inventory for urban clusters surrounding the Yangtze River Basin, analyzing water quality data from 102 cities during 2018–2019. We assessed the exceedance rates for six pivotal indicators: dissolved oxygen (DO), ammonia nitrogen (NH3–N), chemical oxygen demand (COD), biochemical oxygen demand (BOD), total phosphorus (TP), and the permanganate index (CODMn) for each city. Employing random forest regression and SHapley Additive exPlanations (SHAP) analyses, we identified the spatiotemporal factors influencing these key indicators. Our results highlight agricultural activities as the primary contributors to the exceedance of all six indicators, thus pinpointing them as the leading pollution source in the basin. Additionally, forest coverage, livestock farming, chemical and pharmaceutical sectors, along with meteorological elements like precipitation and temperature, significantly impacted various indicators' exceedances. Furthermore, we delineate five core urban risk components through principal component analysis, which are (1) anthropogenic and industrial activities, (2) agricultural practices and forest extent, (3) climatic variables, (4) livestock rearing, and (5) principal polluting sectors. The cities were subsequently evaluated and categorized based on these risk components, incorporating policy interventions and administrative performance within each region. The comprehensive analysis advocates for a customized strategy in addressing the discerned risk factors, especially for cities presenting elevated risk levels.

Land degradation and forest fragmentation have been prominent issues in the Amazon since the 1970s, primarily driven by the suppression of primary forests due to land use changes. In this study, we propose an innovative approach by integrating artificial neural networks (ANN) and cellular automata Markov chain (CA‐MA) models to predict future land use and assess the associated forest fragmentation using landscape ecology metrics in the Jamari River Basin. The analysis reveals a significant increase in fragmentation between 1985 and 2018, as evidenced by a rise in the number of fragments from 7162 to 28,170. Moreover, we observed a decrease in the core area from approximately 2.5 million hectares to less than 1 million hectares, accompanied by an increase in edge density from 6 to 18 m.ha−1. Additionally, the average distance between fragments expanded from 66 to 95 m. Highlighting the urgency of addressing this issue, our study emphasizes the necessity of exploring effective strategies within the Brazilian public environmental management system. By utilizing various rural policy planning tools, we aim to tackle unsustainable development and mitigate the adverse impacts of land use changes in the region. In conclusion, this research offers an innovative approach that combines ANN and CA‐MA models to predict land use and assess forest fragmentation, shedding light on the alarming trend of land degradation and providing valuable insights for informed decision‐making and sustainable land management practices. [ABSTRACT FROM AUTHOR]

Climate change, triggered by the direct and indirect effects of urbanization, seriously threatens the ecosystem, earth cycles, and vitality. It is quite complex to investigate the reasons for the devastating effect of extreme events that occur with the impact of climate change. However, future projections based on probabilities are needed for governments and urban planning to develop strategies and manage the crisis on a global scale. This research aims to simulate the effects of climate change on temperature, precipitation, and climate classes, which are the basic parameters in spatio-temporal conditions. In this context, within the framework of SSPs 245 and SSPs 585 scenarios defined by The Intergovernmental Panel on Climate Change (IPCC) reports, forecast maps were produced by using De Martonne (IDM), Emberger (IE), and Lang (IL) indexes in twenty-year periods until 2100. IDM reveals that arid areas not included in the area today will constitute 41.96% of the site according to 2100 models. The IE classification estimates that very humid areas will decrease from 58.36 to 0.23%. According to IL, while humid regions (90.86%) occupy a prominent place, they will reduce to 0.42% in 2100 and turn into semi-humid areas (69.43%). The research presents climate risk and the devastating threat facing the world by simulating shifts in the most common climate classes according to different climate class indexes. [ABSTRACT FROM AUTHOR]

The rapid growth of developing countries has placed unprecedented pressure on water resources, severely hindering the realization of sustainable development goal 6 (SDG 6) in river basins. In this study, sustainable water resource utilization (SWRU) in the Yellow River basin (Shaanxi section) from 2005 to 2019 is evaluated through an analysis of water resource overload combined with the water footprint (WF) and the water planetary boundary (WPB) and an analysis of water resource utilization quality combined with the WF and city development index (CDI) based on the coupled coordination model. Then, the results are incorporated into the drive-pressure-state-impact-response framework to analyze the impacts of the socioeconomic system on SWRU and the feedback effect of related policies. The results show that there were obvious differences in the spatiotemporal evolution characteristics of the WF in different geographical units. The WF of Guanzhong first increased and then decreased, and the WF of Northern Shaanxi grew continuously. The water deficit state is increasing. Although the coordination level between the WF and CDI in the basin increased by 500.31%, it was characterized by nonequilibrium and volatility. Compared to water resource endowment, socioeconomic development and government policies have greater impacts on SWRU; furthermore, the influencing factors demonstrate spatial variability, revealing the complexity of achieving SDG 6 in the basin. As policy implications, adaptive water resource policies should be formulated on the basis of strengthening the overall basin management. This study provides a scientific basis for promoting the realization of SDG 6 through watershed water management. [ABSTRACT FROM AUTHOR]

Basin-based water management strategy is one of the necessary instruments for the protection and sustainable use of water resources against climate change. In this paper, the monthly precipitation distributions of the 25 major basins in Türkiye were produced, and amounts and volumes were computed and analyzed. Only annual modeling and assessments of precipitation may hide months with precipitation shortages. Empirical Bayesian Kriging (EBK), Ordinary Kriging (OK), and Inverse Distance Weighting (IDW) were implemented in interpolation. EBK outperformed in all months and calculations were based on the EBK. The month with the highest precipitation potential in Türkiye is December (77.9 mm, 60.77 billion m3), and the month with the lowest precipitation potential is August (13.8 mm, 10.76 billion m3). In the basins, the monthly precipitation amounts range between 2.7 mm and 185.2 mm, and the volumes range between 0.02 billion m3 and 13.24 billion m3. The basins with the highest precipitation depth were determined as the East Black Sea, Antalya, Asi, and Ceyhan, and the lowest as the Small Menderes, Konya, and Tigris-Euphrates in different months. The monthly precipitation patterns and potentials of the basins vary widely. In May, June, July, August, and September, when water, particularly agricultural irrigation, is required the most, the 20 basins, except for the 5 located in Northern Türkiye precipitation shortage was determined.

Investigating the impact of apple-dominated areas on nitrogen (N) and phosphorus (P) losses at a basin scale was essential for the sustainable development of apple industry in China. This study conducted a survey on fertilizer application and built a Soil and Water Assessment Tool (SWAT) model to quantitatively analyze the N and P losses in the Qixia apple-dominated area. Additionally, the decreases in N and P losses through adjusting the fertilizer application modes were evaluated. Results showed that average N and P losses in the Wulong River Basin (WRB) were 44.4 and 0.365 kg ha−1 in 2011–2017, respectively, and apple orchards accounted for 73.3% and 51.4% of the total N and P losses in the basin. Under nine fertilizer scheduling scenarios, three fertilizer schedule scenarios, automatic fertilizer application (S-AUTO), “one shot” mode (S1), and regulated fertilizer application (S-BSD), had the lowest N and P losses in apple orchards. The decreases in N loss ranged from 20.6% to 26.1% at the subbasin scale and 14.8%–30.7% at the basin outlet when applying the S-AUTO, S1, and S-BSD fertilizer application modes in Qixia apple orchards and all apple orchards in the WRB. The reductions in P loss varied from 22.0% to 46.1% at the subbasin scale and 14.6%–25.6% at the basin outlet. In orchard-dominated basin, N and P losses can be effectively reduced by optimizing the orchard fertilizer scheduling strategies.

Environmental vulnerability is an important tool to understand the natural and anthropogenic impacts associated with the susceptibility to environmental damage. This study aims to assess the environmental vulnerability of the Doce River basin in Brazil through Multicriteria Decision Analysis based on Geographic Information Systems (GIS-MCDA). Natural factors (slope, elevation, relief dissection, rainfall, pedology, and geology) and anthropogenic factors (distance from urban centers, roads, mining dams, and land use) were used to determine the environmental vulnerability index (EVI). The EVI was classified into five classes, identifying associated land uses. Vulnerability was verified in water resource management units (UGRHs) and municipalities using hot spot analysis. The study employed the water quality index (WQI) to assess the EVI and global sensitivity analysis (GSA) to evaluate the model input parameters that most influence the basin's environmental vulnerability. The results showed that the regions near the middle Doce River were considered environmentally more vulnerable, especially the UGRHs Guandu, Manhuaçu, and Caratinga; and 35.9% of the basin has high and very high vulnerabilities. Hot spot analysis identified regions with low EVI values (cold spot) in the north and northwest, while areas with high values (hot spot) were concentrated mainly in the middle Doce region. Water monitoring stations with the worst WQI values were found in the most environmentally vulnerable areas. The GSA determined that land use and slope were the primary factors influencing the model's response. The results of this study provide valuable information for supporting environmental planning in the Doce River basin. [ABSTRACT FROM AUTHOR]

Farmers in the Langhorne Creek–Angas Bremer basin irrigation district of South Australia have faced a series of hydrosocial crises relating to drought and groundwater depletion and degradation. The crises have been negotiated through concerted community engagement and cooperation. Adaptation responses have included a combination of infrastructural development and changes to the licensing, regulation, and oversight of irrigation governance, easing extraction pressures on the local groundwater catchment. However, new risks have emerged in the wake of, and as a result of, these solutions. One aspect of the solution has been to connect the Angas Bremer basin district more intimately to the much larger continental riverine system, the Murray-Darling basin, which stretches across multiple regional and state jurisdictions. The very success of that scalar response to hydrological risk generates broader systemic risks: to water supply and quality from climate change and upstream extraction; to basin governance; and to community cohesion, engagement, flexibility, and resilience. In a post-crisis period, there is a need to understand the emergent risks from transformational adaptation and guard against complacency to ensure that the hydrosocial qualities of flexibility and resilience that enabled positive responses to the initial crises endure to respond to future crises in water supply and its management.

Under the influence of global climate change and urbanization processes, the number of available water resources (AWRs) in basins has become significantly more uncertain, which has restricted the sustainable development of basins. Therefore, it is important for us to understand the relationship between land use (LU) patterns and climate change on AWRs in a basin for sustainable development. To this end, the vector autoregressive (VAR) method was adopted to construct a quantitative model for AWRs in the basin in this study. Taking the Yiluo River Basin (YRB) as an example, the dynamic relationship between the five elements of agricultural land (AD), woodland (WD), grassland (GD), construction land (CD), and annual precipitation (PREP) and AWRs in the basin was studied. The results show the following: (1) The constructed VAR model was stable, indicating that the use of the proposed VAR model to characterize the degree of the effect of LU pattern and PREP on AWRs in the YRB was reasonable and effective. (2) AWRs in the YRB showed a downward trend, and their responses to the change in LU and PREP were delayed. The changes in the AWRs in the YRB tended to occur the year after changes to the LU pattern and PREP occurred. (3) In the long run, the degree of the contribution of each influencing factor to changes to AWRs was 23.76% (AD), 6.09% (PREP), 4.56% (CD), 4.40% (WD), and 4.34% (GD), which meant that the impact of the LU pattern was more than 90%. This study provides new ideas for similar research, water resource allocation, and LU planning in other river basins from a macroscopic perspective. [ABSTRACT FROM AUTHOR]

Water is an indispensable resource for human being and the environment. This study analyses spatial distribution of water reservoirs in the Sota catchment with regards to livestock density, population density, rainfall distribution and geological structure of the Sota catchment, and assessed the state of these reservoirs. To this end, the geographic coordinates of water reservoirs were collected and the updated database of reservoirs census in Benin, was used. In addition, livestock and population census database, rainfall data from 1980 to 2016 of twelve (12) stations and geological database were processed in ArcGIS for generating respectively the spatial layers of livestock, population, rainfall and geological map of the catchment. The reservoirs' state has been appreciated by documents exploration and in situ observations. Single factor Regression analysis was conducted to understand the relation of each of the factors with the spatial distribution of the reservoirs in the Sota catchment. The results reveal that Sota catchment contains 35 small water reservoirs mostly concentrated in its central western and south western part. The reservoir density is 0.0026 km−2. Most of the reservoirs are located within areas where livestock density, population density and rainfall amount is high: 51%, 46% and 86% respectively. However, no significant relation was found between reservoirs distribution and livestock density, population density, and rainfall respectively in the catchment. The basement geological structures of the Sota catchment are associated with 71% of the reservoirs' location. The reservoirs are threatened by siltation, lack of pastoral facilities, poor maintenance and management. In fact, 100%, 86%, 74%, 71%, 40%, and 34% of reservoirs are respectively subjected to the issues of: absence of waterers, siltation, deteriorated dyke, eutrophication, inexistent management committee, and drying up in dry season. For sustainable local development purposes, more attention should be paid to basin management planning for construction of new reservoirs and to reservoirs ‘maintenance. Future research on the reservoirs’ sustainability and monitoring surveillance are recommended.

Many Andean forests of Northwestern Patagonia have expanded over burned areas during the last century. In this article, we combine maps from early 1900s with potential distribution models based on recent forest cover maps of the region to estimate the long-term responses of the three main forest communities of seed-obligate forests, Nothofagus pumilio, N. dombeyi and Austrocedrus chilensis, to land-use changes within the Manso river basin. This valley has the highest potential for forest management in the Rio Negro Province. Our results indicate that the forest area of the Manso river basin has doubled over the last 100 years. The lenga forests expanded over xeric shrublands in the valley, coihue forests advanced primarily over burned areas at the beginning of the 20th century, while cypress forests advanced both in shrublands and burned areas. Land cover change analysis indicates that A. chilensis forests are the community with the highest relative increment. We conclude that, under current scenarios of climate change, shrubland management combined with a strategy of conversion to productive N. dombeyi and A. chilensis forests in key areas would improve current policy, which is characterized by a lack of forest management in areas under the National Park System as well as under provincial administration. [ABSTRACT FROM AUTHOR]

The integrated assessment of stream networks and terrestrial land use contributes a critical foundation for understanding and mitigating potential impacts on stream ecology. Riparian zone delineation and management is a key component for regulating water quality, particularly in agricultural watersheds. We present a national assessment of riparian zone land uses according to stream order for the entire hydrological network in the Uruguayan landscape in Southeastern South America. We classified over 82,500 km of streams and rivers in Uruguay into seven Strahler order classes and delineated riparian buffers of 100 and 500 m, depending on stream order, covering a total of 13% of the terrestrial land area in Uruguay. Natural vegetation cover in riparian zones averaged 77% among basins, whereby natural grassland dominated first and second order stream buffers at 58% and 49%, respectively. This highlighted the importance of grasslands in headwater regions of the country. Riparian forests formed corridors along larger streams, representing a mere 9% of buffers in first order streams but reaching 46% of buffers of 6th order streams. Among the six major basins of Uruguay, we found differences in the relative importance of riparian forests and crop cover in headwater stream riparian zones, as well as differences in relative crop cover within riparian zones. Results show that streams in subtropical grassland landscapes originate in open grassland environments, which has major implications for thermal regimes, carbon inputs, and stream biodiversity. Riparian buffer management should consider geographic differences among different basins and ecoregions within Uruguay. [ABSTRACT FROM AUTHOR]

Large-scale decarbonization through carbon capture and storage (CCS) may likely involve many commercial-scale CO 2 storage projects located in proximity. Large volumes of CO 2 injected will elevate reservoir pressures and may lead to rapid convergence of fracture pressure thresholds. This analysis employs numerical modeling to analyze how CO 2 plumes and pressure fronts evolve when CO 2 is injected into a single storage formation from multiple projects located in proximity. This analysis also evaluates the extent to which injection well spacing alleviates pressure buildup in the absence of active pressure management tactics. The simulation approach was based on a single, homogenous saline aquifer in which CO 2 injection occurs under a one-injector baseline case and several multi-well cases where well spacing varies. Analysis results show that the extent of pressure buildup is in the range of tens or a few hundreds of kilometers and contingent upon the defining pressure buildup demarcating the front edge. For the geological setting evaluated in this paper, our analysis suggests that without active basin pressure management strategies, commercial-scale projects would likely need to be sited far apart to avoid pressure interference from one another. Analysis results show the radius of CO 2 plume varies approximately from 2 to 3 km from injection wells (each injecting 1 Mt/year for 30 years) depending on cases and modeling parameters assumed. Given the pressure interference, this paper thus draws attention to the importance of greater coordination among storage operators and regulatory stakeholders. Because this analysis assumes a very specific geologic situation, this exploratory analysis bears further investigations across other geologic situations. • This paper conceptualized a foundational modeling and simulation studies exploring possibilities and strategies of basin scale CO 2 storage. This will provide the first considerations of basin scale CO 2 storage. • Multiple scenarios offer insights of injection designs and operations impact on the reservoir pressure and CO 2 plumes through various injection schemes and strategies. • Pressure interference and associated discussions provide much extensive understanding of basin scale CO 2 storage that can be easily applied to industry and real field by adapting reservoir heterogeneity and operation designing. [ABSTRACT FROM AUTHOR]

Research shows that regularly performed land use/land cover (LU/LC) variation detection is recommended to support different prospect organizations and management activities to resolve a variety of environmental problems. The current research aims to investigate the LU/LC pattern and measure the corresponding alteration in the arid and semi-arid climatic conditions by considering the Lesser Zab catchment, northeastern Iraq, as a typical basin area. Data from Landsat imageries for the years 1989, 1999, 2009, 2019, and 2021 were utilized. Generally, seven general classes have been noted within the study area through applying a supervised image classification process. Urban lands in 1989 covered 0.46%; however, in 2021, the urban lands increased to 5.59% compared to 1989. Agricultural lands were reduced by 11.1% between 1989 and 2021. It was identified that there has been a quick transformation from agricultural lands to urban lands. The studied basin witnessed a reduction trend in barren and agricultural lands, although urban lands experienced expansion. Whereas, a fluctuation in the occupied area by the water bodies and forest lands has been recorded during the studied period. Analyzing the spatiotemporal pattern of LU/LC would support strategy makers' detection to cope with the undesired impact of such an event. The unwanted impact of difficult ecological dynamics in the basin would be mitigated by giving particular attention to recovering the affected area to protect the basin's natural resources. [ABSTRACT FROM AUTHOR]

Under the influence of global climate change and urbanization processes, the number of available water resources (AWRs) in basins has become significantly more uncertain, which has restricted the sustainable development of basins. Therefore, it is important for us to understand the relationship between land use (LU) patterns and climate change on AWRs in a basin for sustainable development. To this end, the vector autoregressive (VAR) method was adopted to construct a quantitative model for AWRs in the basin in this study. Taking the Yiluo River Basin (YRB) as an example, the dynamic relationship between the five elements of agricultural land (AD), woodland (WD), grassland (GD), construction land (CD), and annual precipitation (PREP) and AWRs in the basin was studied. The results show the following: (1) The constructed VAR model was stable, indicating that the use of the proposed VAR model to characterize the degree of the effect of LU pattern and PREP on AWRs in the YRB was reasonable and effective. (2) AWRs in the YRB showed a downward trend, and their responses to the change in LU and PREP were delayed. The changes in the AWRs in the YRB tended to occur the year after changes to the LU pattern and PREP occurred. (3) In the long run, the degree of the contribution of each influencing factor to changes to AWRs was 23.76% (AD), 6.09% (PREP), 4.56% (CD), 4.40% (WD), and 4.34% (GD), which meant that the impact of the LU pattern was more than 90%. This study provides new ideas for similar research, water resource allocation, and LU planning in other river basins from a macroscopic perspective.

The Jordan River system is one of the most iconic and most contested river systems in the world. The once "mighty Jordan", which has served as the primary source of water for populations in several countries, is currently a severely denuded river system, with only a fraction of its historic flow. Several initiatives, however, aim to restore some of the basin's flows. This paper will provide a historical overview and analysis of the trajectory of the Jordan River system from being a primary supplier of water to a desiccated shadow of its former glory. It highlights the critical role international borders played in dividing control over the basin, resulting in different types and levels of water scarcity experienced by each of the basin's riparians, each of whom has implemented different strategies to cope with such scarcity. The paper then presents several plans for large-scale interbasin transfers involving desalinated water initiated by basin riparians in attempts to deal with water scarcity and highlights how these planned initiatives are set to transform the basin from a regional supplier of water to a net importer. [ABSTRACT FROM AUTHOR]

Water governance in the EU is enshrined in the Water Framework Directive (WFD), with the engagement of stakeholders being one of the governance cornerstones. The inclusion of the interests of scientific and non-scientific groups in decision-making is crucial. Our objective is to examine the contribution of the participatory approach to the effectiveness of local water resource management. Within the Eye4water project, a participatory assessment was applied for the Lissos river basin, through joint identification and evaluation of the main water-related issues. Firstly, we identified the social system engaged to the basin through stakeholders’ mapping. Secondly, based on criteria selection, three stakeholders’ groups were invited to a workshop. Our preliminary results show that mutual learning should be encouraged at multiple levels. Well-recognized threats such as water pollution, flood risk, and groundwater lowering are present, while biodiversity issues are quite underrepresented.

With global warming, the contradiction between the supply and demand of water resources is increasingly prominent in arid areas. Enhancing water resource management is an important way to alleviate the shortage of ecological water supply and improve ecosystem services in arid river basins. However, previous studies have rarely conducted comprehensive function zoning of ecosystem services using two aspects: category (quantity) and strength change (quality), based on the changes in ecosystem services. In this regard, two scientific problems need to be solved:(1) quantifying the temporal and spatial changes of ecosystem services and (2) conducting function zoning of ecosystem services in terms of quantity and quality. To answer these two questions, we took the upper and middle reaches of the Tarim River Basin in China as the study area. According to the eco-environmental characteristics of arid basins, this study measured four key indices: carbon storage (CAS), evapotranspiration (ET), temperature vegetation dryness index (TVDI) and groundwater depth (GWD). We used the related model to quantitatively analyze the spatial and temporal distribution of these four indicators and the spatial aggregation characteristics of increases and decreases. We used the Reclassify tool of ArcGIS 10.5 to classify areas with more than two important zones as high-quantity ecosystem services zones. We used factor analysis, combined with Quantile, to divide ecosystem service quality into high-quality and low-quality zones. Considering the quantity and quality of ecosystem services, we divided ecosystem services into important, general, sensitive and fragile ecosystem services zones. Based on comprehensive zoning results during 2000–2018, an ecosystem services restoration zoning was determined. We used correlation analysis to analyze the basic drivers of changes in these four indicators. The results showed that during 2000–2018, CAS and ET in the Tarim River Basin increased by 0.2% and 15.3%, respectively, TVDI decreased by 22.5% and GWD rose by 1.7%. In 2018, the hot spots of CAS, ET, TVDI and GWD accounted for a small proportion of the whole study area, accounting for 3.8%, 5.9%, 9.0% and 1.4%, respectively. Compared with 2000, the high-quantity zone of ecosystem services increased by 10.7% and the high-quality zone of ecosystem services increased by 2.0% in 2018. This clearly showed that water diversion and riverway loss were the main factor driving changes in ecosystem services. In terms of maintaining groundwater depth and increasing vegetation coverage, specific counter measures and suggestions for increasing the number of ecosystem services (“increment”) and improving the quality of ecosystem services (“quality improvement”) were proposed. This study can provide a scientific reference for achieving optimal management of water resource systems for similar river basins in arid regions.

Objective: To estimate the potential and current water erosion in the Necaxa system and to propose alternatives aimed to reduce the siltation problem in the hydraulic infrastructure. Design/methodology/approach: The Universal Soil Loss Equation (USLE) was applied, using a Geographic Information System to process the map algebra. Results: The current estimated water erosion was 159 t ha-1 per year; this factor impacts the loss of farmland and soil nutrients, the accumulation of matter towards urban areas, the siltation of riverbeds and dams, and the loss of the system's hydraulic works capacity. Study limitations/implications: No data about runoff plots in the field is available; therefore, it is not possible to compare current water erosion values with those obtained by the USLE applied, using the map algebra technique. Findings/conclusions: The reforestation and conservation agriculture proposal would help to reduce erosion to 16 t ha-1 per year. However, if control actions are not carried out and the current vegetation cover is not preserved, the problem can increase until it reaches potential erosion values >200 t ha-1 per year. [ABSTRACT FROM AUTHOR]

The protection of the Yangtze River Basin is a top priority in China, and the National People's Congress (NPC) Standing Committee has started to draft a new protection legislation specifically for the Yangtze River Basin. The Basin forms the epicenter of environmental, social, and economic life. Any efforts to protect the Basin must accommodate several competing interests from a multiplicity of interested parties and stakeholders such as local governments, villages, and business enterprises. Current relevant institutions and organizations are unable to sufficiently ensure environmental protection and green development in the Basin. The NPC Standing Committee must thus adopt a more holistic approach when creating new protection legislations aimed at the Yangtze River Basin.

The Circular Economy set a frame to govern sustainable growth. Laspias river basin (Thrace) is characterized by various land and water uses and pressures posed directly and/or indirectly on the riverine system which acts as a burdened receptor. The aim is to prioritize threats in the basin and to further recognize the causality relationships in main elements affecting water management parameters that fall upon circular economy using enhanced DPSIR, Decision Making Trial and Evaluation Laboratory (DEMATEL) techniques. To assess the status quo, circular economy principles were adopted using a sustainable water management perspective embedded in DPSIR to link the causes and effects components. The key criteria based on the cause-factors were mined simplifying the multicriteria analysis of the effects. Findings highlight the multiplicity of pressures and origin of the impacts. This method proved as a valuable tool to track threats prior to stakeholder mapping for participatory management.

The extent and intensity of impacts of multiple new dams in the Amazon basin on specific biological groups are potentially large, but still uncertain and need to be better understood.It is known that river disruption and regulation by dams may affect sediment supplies, river channel migration, floodplain dynamics, and, as a major adverse consequence, are likely to decrease or even suppress ecological connectivity among populations of aquatic organisms and organisms dependent upon seasonally flooded environments.This article complements our previous results by assessing the relationships between dams, our Dam Environmental Vulnerability Index (DEVI), and the biotic environments threatened by the effects of dams. Because of the cartographic representation of DEVI, it is a useful tool to compare the potential hydrophysical impacts of proposed dams in the Amazon basin with the spatial distribution of biological diversity. As the impact of Amazonian dams on the biota of both rivers and periodically flooded riparian environments is severe, DEVIs from different Amazonian tributary basins are contrasted with patterns of diversity and distribution of fish, flooded forest trees and bird species.There is a consistent relationship between higher DEVI values and the patterns of higher species richness and endemism in all three biological groups. An assessment of vulnerability at the scale of tributary basins, the assessment of biodiversity patterns related to DEVI, and the analysis of teleconnections at basin scale, demonstrate that recent construction of dams is affecting the biota of the Amazon basin.The evidence presented here predicts that, if currently planned dams are built without considering the balance between energy production and environmental conservation, their cumulative effects will increase drastically and represent a major threat to Amazonian biodiversity. [ABSTRACT FROM AUTHOR]

The Jordan River system is one of the most iconic and most contested river systems in the world. The once “mighty Jordan”, which has served as the primary source of water for populations in several countries, is currently a severely denuded river system, with only a fraction of its historic flow. Several initiatives, however, aim to restore some of the basin’s flows. This paper will provide a historical overview and analysis of the trajectory of the Jordan River system from being a primary supplier of water to a desiccated shadow of its former glory. It highlights the critical role international borders played in dividing control over the basin, resulting in different types and levels of water scarcity experienced by each of the basin’s riparians, each of whom has implemented different strategies to cope with such scarcity. The paper then presents several plans for large-scale interbasin transfers involving desalinated water initiated by basin riparians in attempts to deal with water scarcity and highlights how these planned initiatives are set to transform the basin from a regional supplier of water to a net importer.

Effective management of large basins necessitates pinpointing the spatial and temporal drivers of primary index exceedances and urban risk factors, offering crucial insights for basin administrators. Yet, comprehensive examinations of multiple pollutants within the Yangtze River Basin remain scarce. Here we introduce a pollution inventory for urban clusters surrounding the Yangtze River Basin, analyzing water quality data from 102 cities during 2018-2019. We assessed the exceedance rates for six pivotal indicators: dissolved oxygen (DO), ammonia nitrogen (NH 3 -N), chemical oxygen demand (COD), biochemical oxygen demand (BOD), total phosphorus (TP), and the permanganate index (COD Mn ) for each city. Employing random forest regression and SHapley Additive exPlanations (SHAP) analyses, we identified the spatiotemporal factors influencing these key indicators. Our results highlight agricultural activities as the primary contributors to the exceedance of all six indicators, thus pinpointing them as the leading pollution source in the basin. Additionally, forest coverage, livestock farming, chemical and pharmaceutical sectors, along with meteorological elements like precipitation and temperature, significantly impacted various indicators' exceedances. Furthermore, we delineate five core urban risk components through principal component analysis, which are (1) anthropogenic and industrial activities, (2) agricultural practices and forest extent, (3) climatic variables, (4) livestock rearing, and (5) principal polluting sectors. The cities were subsequently evaluated and categorized based on these risk components, incorporating policy interventions and administrative performance within each region. The comprehensive analysis advocates for a customized strategy in addressing the discerned risk factors, especially for cities presenting elevated risk levels., (© 2024 The Authors.)

The Freshwater Health Index (FHI) toolbox is an open source software in C# developed to guide ecological management of freshwater systems. It provides functionality to calculate basin-level freshwater social-ecological indicators, with algorithms for selected indicators also integrated with support for processing geospatial datasets. The toolbox archives the data necessary for calculating the indicators and can serve as a collaborative platform in a basin by providing users with the ability to initiate, edit and share a common freshwater basin database. Now available at GitHub and through the FHI website, the FHI toolbox offers a convenient yet rigorous way for basin-level freshwater management to maintain continuity and reproducibility amid numerous indicators assessed for freshwater basins. Funding statement: This paper was written as part of the Freshwater Health Index development, funded by Victor and William Fung Foundation Limited, Betty and Gordon Moore, the Borrego Foundation, Flora Family Foundation and Starwood Foundation.

The Freshwater Health Index (FHI) toolbox is an open source software in C# developed to guide ecological management of freshwater systems. It provides functionality to calculate basin-level freshwater socialecological indicators, with algorithms for selected indicators also integrated with support for processing geospatial datasets. The toolbox archives the data necessary for calculating the indicators and can serve as a collaborative platform in a basin by providing users with the ability to initiate, edit and share a common freshwater basin database. Now available at GitHub and through the FHI website, the FHI toolbox offers a convenient yet rigorous way for basin-level freshwater management to maintain continuity and reproducibility amid numerous indicators assessed for freshwater basins. [ABSTRACT FROM AUTHOR]

This paper focuses on the application of the concept of Integrated Water Resources Management (IWRM) in Tanzania. It asks: how did IWRM affect the rural and fast-growing majority of smallholder farmersʼ access to water which contributes directly to poverty alleviation and employment creation in a country where poverty and joblessness are high? Around 1990, there were both a strong government-led infrastructure development agenda and IWRM ingredients in place, including cost-recovery of state services aligning with the Structural Adjustment Programmes, water management according to basin boundaries and the dormant colonial water rights (permits) system. After the 1990s, the World Bank and other donors promoted IWRM with a strong focus on hydroelectric power development, River Basin Water Boards, transformation of the water right system into a taxation tool, and assessment of environmental flows. These practices became formalised in the National Water Policy (2002) and in the Water Resources Management Act (2009). Activities in the name of IWRM came to be closely associated with the post-2008 surge in large-scale land and water deals. Analysing 25 years of IWRM, the paper identifies the processes and identities of the losers (smallholders and – at least partially – the government) and the winners (large-scale water users, including recent investors). We conclude that, overall, IWRM harmed smallholdersʼ access to water and rendered them more vulnerable to poverty and unemployment.

Rivers are aquatic systems with a unidirectional flow. These systems are highly diverse habitats that support a great variety of organisms, which vary in shape and function, and sustain a diverse range of hydrological ecosystem services (HESs). The HESs provided by rivers varies based on complex hydro-geomorphological dynamics and their relationship with the functional processes of the basin. Land use changes in transition zones, where ecosystem functions are compromised, affect the basin, especially basins close to or on the periphery of urban areas. Such is the case for Mexico City, where 60 m3 of water is consumed per second, 30% of which is imported from outside sources. The rivers of the Magdalena–Eslava sub-basin are among the few remaining surficial water sources in Mexico City. These rivers are located in an area classified as a Soil Conservation Zone, which has been intensely managed for decades. The aims of this paper are (1) to perform a hydrological evaluation of two urban streams and identify their relationship with the provision of hydrological ecosystem services via (i) a hydraulic balance analysis, (ii) a hydro-geomorphological characterization of each stream, (iii) an estimate of present and potential hydraulic erosion, (iv) the determination of physicochemical and bacteriological parameters and (v) a description of macroinvertebrates, macroalgae and their habitats in order to (2) identify the impacts of socio-economic dynamics on the responses of this rural-urban lotic system. Our results show that water flow, forest cover and hydro-geomorphologic heterogeneity are key to sustaining ecosystem functioning, especially in the high and middle sections of the basin. The highest potential provision of water for direct use was recorded in the sub-basin’s middle section; however, the stream channels in that section have lost their natural water flow due to a water management infrastructure built to regulate flow during the rainy season. This intervention can be viewed as a regulation of HESs as water management infrastructure alters the transport of sediment and reduces available natural habitat. The provision of quality water in the lower area of the sub-basin has been seriously compromised by the establishment of illegal urban settlements. A relationship between biologically diverse ecological traits and their response capabilities was established and can be considered an indicator of current HES potential. Therefore, this sub-basin may constitute an example of good management and maximizing potential HESs in an urban-rural setting based on improved management strategies that could be applied in other developing nations.

This paper presents a decision support system (DSS) based on formal methods for the management of complex river basins in flood scenarios. The DSS is the result of integrating two different DSSs: first, a DSS for dam management that uses the SPIN model checker to produce the manoeuvres and the discharged water over time to satisfy user-defined constraints; second, a DSS that performs numeric simulations of rainfall and water flow along the river basin, taking into account the water discharged by dams. By integrating these two DSSs, the user can define constraints over the parameters of the river basin and all the dams. We use SPIN to find the sequences of dam manoeuvres that mitigate the effect of floods along the river basin, according to these constraints. This work is part of the SAID project, a European demonstration project whose main goal is to smartly manage river basins by means of the integration of different DSSs. The demonstrator basin is the Guadalhorce river basin, located in the south of Spain. We apply the method to develop a DSS for this river basin in particular, but the approach is general enough that it can be applied to any river basin. [ABSTRACT FROM AUTHOR]

Abstract: The main scope of the paper is the implementation of future scenarios in the Lower Danube basin, supporting the development of River Basin Management Plans and future environmental policies. The 800 000 km2 Danube River Basin extends across 19 countries, of which 14 are contracting parties of the ICPDR. The Lower Danube is occupied mostly by Romania, including the Danube Delta. The Danube Delta hydrological complex covers 5800 km2 comprising over 300 lakes, three main branches and a vast network of channels. Changes impacting significant ecosystem services such as recreation, fishing, flows, ecotourism, flood regulation, navigation and reed/wood resources have to be evaluated and the quantification of those elements must be performed in order to incorporate them into the modelling process. [ABSTRACT FROM AUTHOR]

Knowledge of the spatial distribution of temporary and perennial river channels in a whole catchment is important for effective integrated basin management and river biodiversity conservation. However, this information is usually not available or is incomplete. In this study, we present a statistically based methodology to classify river segments from a whole river network (Deva-Cares catchment, Northern Spain) as temporary or perennial. This method is based on an a priori classification of a subset of river segments as temporary or perennial, using field surveys and aerial images, and then running Random Forest models to predict classification membership for the rest of the river network. The independent variables and the river network were derived following a computer-based geospatial simulation of riverine landscapes. The model results show high values of overall accuracy, sensitivity, and specificity for the evaluation of the fitted model to the training and testing data set (≥0.9). The most important independent variables were catchment area, area occupied by broadleaf forest, minimum monthly precipitation in August, and average catchment elevation. The final map shows 7525 temporary river segments (1012.5 km) and 3731 perennial river segments (662.5 km). A subsequent validation of the mapping results using River Habitat Survey data and expert knowledge supported the validity of the proposed maps. We conclude that the proposed methodology is a valid method for mapping the limits of flow permanence that could substantially increase our understanding of the spatial links between terrestrial and aquatic interfaces, improving the research, management, and conservation of river biodiversity and functioning. [ABSTRACT FROM AUTHOR]

Water resources availability is increasingly constrained, considering the quality and quantity available for use. There is an urgent need of recovering this availability, focusing on the planning and management process of water supply systems. One of the main threats to water resources is related to erosion effects, namely widespread pollution load and the silting of watercourses and reservoirs useful life reduction. The objective of this study was to evaluate water supply systems environmental fragility within the Paulista Macro Metropolis area and to use the results to develop environmental zone classes to orient territorial planning. The study was conducted in seven superficial water supply systems of the aforementioned region. Environmental fragility evaluation was focused on four environmental variables that represent natural vulnerability to erosion, and 2015 land cover map to delineate human influence on erosive processes. Results indicate that Tietê River water supply systems, namely Piracicaba, Capivari and Jundiaí (PCJ) and Itupararanga systems, can be considered the most fragile water supply systems in the study area. The environmental fragility map was used to derive the environmental zoning map, including conservation and priority areas, suitable regions for agriculture expansion, and areas with high needs for restoration efforts. In addition, environmental fragility framework herein can be viewed as a model with high replication potential for regional planning and management in that land cover can be manipulated to minimize environment natural vulnerability, guiding territorial occupation toward a more sustainable landscape design, which subsidizes water resources multiple uses. [ABSTRACT FROM AUTHOR]

The Vistula is the largest river in Poland, which flows from the south to the north. Its mouth is on the Baltic Sea. As for hydrography the Vistula is divided into three parts: Upper – from its sources to the mouth of the River San, Middle – up to the tributary Narew River, and the Lower – up to its mouth on the sea. This article covers the Vistula and its basin management plans starting from the interwar period up to the present day. The location of the Vistula and its basin as well as land cover are described. The division of Poland into river basin districts and water regions accompanied by a description of administrative division of the country are described. Climatic conditions of Poland including precipitation and air temperatures are presented. Basic hydrological data of the Vistula and its basin is given. Parts of the Vistula basin, which are included in the Program of Natura 2000 are mentioned. Brief information concerning existing, more important hydraulic and hydroenergy structures in the main Vistula channel as well as on its tributaries are described.

Water is an indispensable resource for human being and the environment. This study analyses spatial distribution of water reservoirs in the Sota catchment with regards to livestock density, population density, rainfall distribution and geological structure of the Sota catchment, and assessed the state of these reservoirs. To this end, the geographic coordinates of water reservoirs were collected and the updated database of reservoirs census in Benin, was used. In addition, livestock and population census database, rainfall data from 1980 to 2016 of twelve (12) stations and geological database were processed in ArcGIS for generating respectively the spatial layers of livestock, population, rainfall and geological map of the catchment. The reservoirs' state has been appreciated by documents exploration and in situ observations. Single factor Regression analysis was conducted to understand the relation of each of the factors with the spatial distribution of the reservoirs in the Sota catchment. The results reveal that Sota catchment contains 35 small water reservoirs mostly concentrated in its central western and south western part. The reservoir density is 0.0026 km -2 . Most of the reservoirs are located within areas where livestock density, population density and rainfall amount is high: 51%, 46% and 86% respectively. However, no significant relation was found between reservoirs distribution and livestock density, population density, and rainfall respectively in the catchment. The basement geological structures of the Sota catchment are associated with 71% of the reservoirs' location. The reservoirs are threatened by siltation, lack of pastoral facilities, poor maintenance and management. In fact, 100%, 86%, 74%, 71%, 40%, and 34% of reservoirs are respectively subjected to the issues of: absence of waterers, siltation, deteriorated dyke, eutrophication, inexistent management committee, and drying up in dry season. For sustainable local development purposes, more attention should be paid to basin management planning for construction of new reservoirs and to reservoirs 'maintenance. Future research on the reservoirs' sustainability and monitoring surveillance are recommended., Competing Interests: The authors declare no conflict of interest., (© 2023 The Authors.)

The boom in water infrastructure in the Mekong Basin has raised concerns over the annual supply of water and sediment among its riparian communities. By consolidating various datasets, continuous series of sediment load data were estimated for several stations located within the Lower Mekong Basin. At Chiang Saen in Thailand, the nearest station to the Chinese dams, the average sediment load was 79 ± 32 Mt./yr during the pre-dam period of 1965–1991. However, from 2010 to 2019 – during which a series of mega-dams were built in China – the sediment load decreased drastically by 84 % to only 12.5 ± 4.6 Mt./yr. This phenomenon of reduced annual sediment load during the mega-dam era (2010–2019) as compared to during the pre-dam era (1965–1991) can be observed at stations downstream from Luang Prabang (−53 %) to Nong Khai (−62 %) to Khong Chiam (−33 %). One of the drivers of this sediment load crisis is the rapid development of upstream dams. Especially after 2003, Chinese dams have reduced sediment supply to the downstream Mekong Basin severely. Concurrently, there was an increase in sediment contribution from the stretch of the Mekong River from Chiang Saen to Khong Chiam. A positive outcome of this increased sediment contribution was its buffering effect against the reduction in sediment load from the Chinese part of the Mekong Basin. Although sediment load at Kratie – the gateway station before the alluvial stretch comprising the Cambodian floodplains and Vietnam Mekong Delta – decreased from 78 ± 22 Mt./yr (1995–2009) to only 60 ± 21 Mt./yr (2010–2019), the reduction would have been higher without the increased sediment from the Chiang Saen – Khong Chiam stretch. However, with upcoming planned dams in Laos and Cambodia, this buffering effect is likely to be temporary, implying that the sediment load crisis as already experienced by the downstream communities can only become more severe. • Sediment load declined drastically in the Mekong Basin. • Upstream Chinese dams played a large role in the decline. • Increased sediment contribution from Chiang Saen – Khong Chiam stretch. • Sediment crisis will get much more severe. [ABSTRACT FROM AUTHOR]

This paper focuses on the application of the concept of Integrated Water Resources Management (IWRM) in Tanzania. It asks: how did IWRM affect the rural and fast-growing majority of smallholder farmers' access to water which contributes directly to poverty alleviation and employment creation in a country where poverty and joblessness are high? Around 1990, there were both a strong government-led infrastructure development agenda and IWRM ingredients in place, including cost-recovery of state services aligning with the Structural Adjustment Programmes, water management according to basin boundaries and the dormant colonial water rights (permits) system. After the 1990s, the World Bank and other donors promoted IWRM with a strong focus on hydroelectric power development, River Basin Water Boards, transformation of the water right system into a taxation tool, and assessment of environmental flows. These practices became formalised in the National Water Policy (2002) and in the Water Resources Management Act (2009). Activities in the name of IWRM came to be closely associated with the post-2008 surge in large-scale land and water deals. Analysing 25 years of IWRM, the paper identifies the processes and identities of the losers (smallholders and - at least partially - the government) and the winners (large-scale water users, including recent investors). We conclude that, overall, IWRM harmed smallholders' access to water and rendered them more vulnerable to poverty and unemployment. [ABSTRACT FROM AUTHOR]

Pollution emissions into the drainage basin have direct impact on surface water quality. These emissions result from human activities that turn into pollution loads when they reach the water bodies, as point or diffuse sources. Their pollution potential depends on the characteristics and quantity of the transported materials. The estimation of pollution loads can assist decision-making in basin management. Knowledge about the potential pollution sources allows for a prioritization of pollution control policies to achieve the desired water quality. Consequently, it helps avoiding problems such as eutrophication of water bodies. The focus of the research described in this study is related to phosphorus emissions into river basins. The study area is the upper Iguazu basin that lies in the northeast region of the State of Paraná, Brazil, covering about 2,965 km2 and around 4 million inhabitants live concentrated on just 16% of its area. The MoRE (Modeling of Regionalized Emissions) model was used to estimate phosphorus emissions. MoRE is a model that uses empirical approaches to model processes in analytical units, capable of using spatially distributed parameters, covering both, emissions from point sources as well as non-point sources. In order to model the processes, the basin was divided into 152 analytical units with an average size of 20 km2. Available data was organized in a GIS environment. Using e.g. layers of precipitation, the Digital Terrain Model from a 1:10000 scale map as well as soils and land cover, which were derived from remote sensing imagery. Further data is used, such as point pollution discharges and statistical socio-economic data. The model shows that one of the main pollution sources in the upper Iguazu basin is the domestic sewage that enters the river as point source (effluents of treatment stations) and/or as diffuse pollution, caused by failures of sanitary sewer systems or clandestine sewer discharges, accounting for about 56% of the emissions. Second significant shares of emissions come from direct runoff or groundwater, being responsible for 32% of the total emissions. Finally, agricultural erosion and industry pathways represent 12% of emissions. This study shows that MoRE is capable of producing valid emission calculation on a relatively reduced input data basis. [ABSTRACT FROM AUTHOR]

To assess alterations of the rice-growing season as a sustainable option to overcome temporary groundwater storage shortages resulting from flood and drought conditions in the Upper Chao Phraya River basin in Thailand, rice was planted in May (1.5 months earlier) to harvest before seasonal flooding occurred (normally in October). The assessment showed that a cropping intensity (CI) of approximately 1.4 (100% and 40% of the total agricultural area for the wet and dry seasons, respectively) could be supported by the total available water (surface runoff and renewable groundwater storage). Shifting the growing season did not have a negative impact in terms of rice production area, but it did ensure that the area of rice cultivation avoided flooding or surface water shortage conditions. Expanding the rice production area was also assessed; however, this required the implementation of artificial groundwater recharge (AGR). For example, 1.0 km3of AGR annually was enough to support CI equal to 1.5 without experiencing groundwater depletion. [ABSTRACT FROM PUBLISHER]

The construction of the Rogun Dam in the Amu Darya Basin to increase upstream energy generation creates potential trade-offs with existing downstream irrigation, due to the different timing of energy and irrigation water demands. The present analysis, based on a hydro-economic optimization model, shows that cooperative basin-wide maximization of benefits would lead to large increases in upstream hydropower production and only minor changes in downstream irrigation benefits. However, if upstream stations, including Rogun, are managed unilaterally to maximize energy production, hydropower benefits might more than double while irrigation benefits greatly decrease, thereby substantially reducing overall basin benefits. [ABSTRACT FROM AUTHOR]

Monitoring was conducted in a basin with a history of agricultural pollution (mainly due to the spreading of livestock slurry) to evaluate the response of stream water ion concentrations to the change from agricultural land use to forest. We measured pH, electrical conductivity (EC), and major dissolved elements [phosphate (PO4) phosphorus (P), nitrite (NO2) nitrogen (N), nitrate (NO3) N, ammonium (NH4) N, silicon (Si), sodium (Na), potassium (K), calcium (Ca), magnesium (Mg), sulfate (SO4), and chloride (Cl)] in the stream water during the period 1997–2002 at irregular time intervals. Median values were significantly greater in the agricultural period than in the forest period (P < 0.05). Median pH values remained slightly acidic (5.8–6) for both land uses. NO3-N was the dominant form of dissolved inorganic nitrogen (DIN) under both land uses (agricultural use: 80 percent; forest use: 98 percent. In the forest period, the median PO4-P and NH4-N concentrations were reduced by 95 percent compared to the agricultural period. The median NO2-N and K concentrations decreased by 83 percent and 70 percent, respectively, whereas NO3-N, Cl, Na, and Si showed minor differences (decreases of 15–20 percent). These findings are consistent with the poor agricultural management practices that have been developed in the basin, especially as regards the application of slurry. [ABSTRACT FROM PUBLISHER]

During the construction and especially water filling periods of Keban and Atatürk dams in the Euphrates River Basin, there have been a series of high level political tensions among Turkey, Syria, and Iraq for the allocation of trans-boundary water resources. It has been claimed that those large investments not only contribute to those investing countries but also to those affected ones. This research measures the contributions and impacts of major investments on the basin to the riparian countries. And how spatial land use decisions on irrigated agricultural areas in rival basin countries are made by means of optimization techniques. The model application is based on with and without analyses for the selected group of dams, which are Keban, Karakaya, Atatürk, Ilisu, Tabqa, Haditha, and Mosul dams, Habbaniye Reservoir, and Urfa Tunnels. The mixed integer programming (MIP) based on the Inter Temporal Euphrates and Tigris River Basin Model (ITETRBM) is used as an optimization tool for the necessary analysis. The impacts are presented by countries and by the generated economic benefits, water withdrawals, coverage areas of irrigated agricultural land, cities feasibly supplied from the reservoirs. The results have shown that large reservoirs in Turkey provide extensive contribution to the basin countries especially during drought periods when all major reservoir investments are considered together. That can be considered as potential for coalition during drought periods instead of competition. [ABSTRACT FROM AUTHOR]

The integrated assessment of stream networks and terrestrial land use contributes a critical foundation for understanding and mitigating potential impacts on stream ecology. Riparian zone delineation and management is a key component for regulating water quality, particularly in agricultural watersheds. We present a national assessment of riparian zone land uses according to stream order for the entire hydrological network in the Uruguayan landscape in Southeastern South America. We classified over 82,500 km of streams and rivers in Uruguay into seven Strahler order classes and delineated riparian buffers of 100 and 500 m, depending on stream order, covering a total of 13% of the terrestrial land area in Uruguay. Natural vegetation cover in riparian zones averaged 77% among basins, whereby natural grassland dominated first and second order stream buffers at 58% and 49%, respectively. This highlighted the importance of grasslands in headwater regions of the country. Riparian forests formed corridors along larger streams, representing a mere 9% of buffers in first order streams but reaching 46% of buffers of 6th order streams. Among the six major basins of Uruguay, we found differences in the relative importance of riparian forests and crop cover in headwater stream riparian zones, as well as differences in relative crop cover within riparian zones. Results show that streams in subtropical grassland landscapes originate in open grassland environments, which has major implications for thermal regimes, carbon inputs, and stream biodiversity. Riparian buffer management should consider geographic differences among different basins and ecoregions within Uruguay., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)