The sharing of water between society and ecosystems: from conflict to catchment-based co-management

Ecological Sustainability Assessment of Water Distribution for the Maintenance of Ecosystems, their Services and Biodiversity

Water provision and distribution are subject to conflicts between users worldwide, with agriculture as a major driver of discords. Water sensitive ecosystems and their services are often impaired by man-made water shortage. Nevertheless, they are not sufficiently included in sustainability or risk assessments and neglected when it comes to distribution of available water resources. The herein presented contribution to the Sustainable Development Goals Clean Water and Sanitation (SDG 6) and Life on Land (SDG 15) is the Ecological Sustainability Assessment of Water distribution (ESAW-tool). The ESAW-tool introduces a watershed sustainability assessment that evaluates the sustainability of the water supply-demand ratio on basin level, where domestic water use and the water requirements of ecosystems are considered as most important water users. An ecological risk assessment estimates potential impacts of agricultural depletion of renewable water resources on (ground)water-dependent ecosystems. The ESAW-tool works in standard GIS applications and is applicable in basins worldwide with a set of broadly available input data. The ESAW-tool is tested in the Danube river basin through combination of high-resolution hydro-agroecological model data (hydrological land surface process model PROMET and groundwater model OpenGeoSys) and further freely available data (water use, biodiversity and wetlands maps). Based on the results, measures for more sustainable water management can be deduced, such as increase of rainfed agriculture near vulnerable ecosystems or change of certain crops. The tool can support decision making of authorities from local to national level as well as private enterprises who want to improve the sustainability of their supply chains.

Variations in Groundwater Level and Microtopography Influence Desert Plant Communities in Shallow Aquifer Areas

An improved understanding of the relationships among vegetation, groundwater level, and microtopography is crucial for making well-informed management decisions in areas with shallow groundwater resources. We measured plant species abundance/composition and richness in relation to depth to groundwater (DTW) and microtopography in Owens Valley, California, particularly in areas where DTW ranged from 0 to 4 m. Sampling occurred along 67 vegetation transects across three community types. Relationships between DTW and community composition were evaluated using non-metric multidimensional scaling (NMS), while non-parametric multiplicative regression was used to relate DTW and microtopography to species abundance. The dominant gradient in species composition (NMS Axis 1) explained ~51% of variation in our distance matrix and was most strongly associated (r = 0.55) with DTW. The graminoids Juncus arcticus, Leymus triticoides, and Distichlis spicata had strong affinities toward areas with the shallowest DTW (<1.5 m). One salt-adapted species Sporobolus airoides and one shrub Ericameria nauseosa dominated areas with intermediate DTW (1.5-2.0 m), whereas the shrubs Atriplex torreyi, Sarcobatus vermiculatus, and Artemisia tridentata were dominant in areas with deeper DTW (>2.0 m). Variation in microtopography affected species abundance and increased species richness for vegetation communities at either extreme of the water table gradient, shallow, and deep DTW but not the intermediate DTW. Findings indicate that desert plant communities from shallow aquifers have adapted to different DTW and microtopography conditions and that considering those adaptations may be important to manage groundwater and vegetation resources in these areas.

Evaluating the health risks of heavy metals from vegetables grown on soil irrigated with untreated and treated wastewater in Arba Minch, Ethiopia

Available freshwater scarcity significantly affects sustainable food production for the rapidly growing population. This problem has forced people in most parts of the world to use wastewater as a viable solution. However, wastewater reuse has some deleterious effects on human and environmental health. This study was designed to investigate the health risks (HRs) of heavy metals (HMs) from vegetables irrigated with untreated and treated wastewater. The composite wastewater was collected at various sites in Arba Minch town and subjected to aerobic-anoxic treatment. Treated and untreated wastewater (UTW) was used to irrigate vegetables (lettuce, cabbage and tomato), and HM results were compared with the control (tap water) and standards. Water, soil and vegetables were investigated for various physical and chemical properties. Human health effects due to vegetable consumption were analyzed using HR- index (HRI), target hazard quotient (THQ) and hazard index (HI). The results revealed that most of the water quality indexes were significantly enhanced after aerobic-anoxic treatment, suggesting that wastewater collected from different sites was suitable for biodegradation. Soil physicochemical analyses also showed that pH, cation exchange capacity, organic carbon and organic matter were higher for UTW irrigated soil. Heavy metal concentrations were relatively greater in soils than water used for irrigation purposes and vegetables. The HM concentration in vegetables was higher for UTW than for treated and tap water irrigated vegetables. In vegetables, the order of HM content was Fe > Mn > Zn > Pb > Cu > Cd. Tomato followed by cabbage and lettuce accumulated significant amount of HMs (Fe > Mn > Zn > Pb > Cu > Cd) in their different organs (fruit/leaf>root>stem). The individual and combined health indexes (HRI, THQ and HI) showed that Pb and Cd have values greater than unity for wastewater irrigated vegetables, which could result in non-carcinogenic disease for short/lifetime exposure in adults and children. Overall, consumption of vegetables can be safer when grown with treated effluent than with UTW.

Physiological, Nutritional and Metabolomic Responses of Tomato Plants After the Foliar Application of Amino Acids Aspartic Acid, Glutamic Acid and Alanine

Agriculture is facing a great number of different pressures due to the increase in population and the greater amount of food it demands, the environmental impact due to the excessive use of conventional fertilizers, and climate change, which subjects the crops to extreme environmental conditions. One of the solutions to these problems could be the use of biostimulant products that are rich in amino acids (AAs), which substitute and/or complement conventional fertilizers and help plants adapt to climate change. To formulate these products, it is first necessary to understand the role of the application of AAs (individually or as a mixture) in the physiological and metabolic processes of crops. For this, research was conducted to assess the effects of the application of different amino acids (Aspartic acid (Asp), Glutamic acid (Glu), L-Alanine (Ala) and their mixtures Asp + Glu and Asp + Glu + Ala on tomato seedlings (Solanum lycopersicum L.). To understand the effect of these treatments, morphological, physiological, ionomic and metabolomic studies were performed. The results showed that the application of Asp + Glu increased the growth of the plants, while those plants that received Ala had a decreased dry biomass of the shoots. The greatest increase in the growth of the plants with Asp + Glu was related with the increase in the net CO2 assimilation, the increase of proline, isoleucine and glucose with respect to the rest of the treatments. These data allow us to conclude that there is a synergistic effect between Aspartic acid and Glutamic acid, and the amino acid Alanine produces phytotoxicity when applied at 15 mM. The application of this amino acid altered the synthesis of proline and the pentose-phosphate route, and increased GABA and trigonelline.

Biologia Futura: integrating freshwater ecosystem health in water resources management

Sustainable water use implies the simultaneous protection of water quality and quantity. Beyond their function to support human needs such as drinking water provision, transportation and recreation freshwater bodies are also habitats. Conceiving them as water users on their own with respective biological, physico-chemical and morphological requirements could help maintaining their healthy state. Healthy freshwater ecosystems are also attractive for high-value human uses. Dwindling per capita availability of water, increasing demands, human well-being and climate change lead to competition for, and pressures on freshwater ecosystems. This has been conceptualized through the modification of the drivers–pressures–state–impacts–responses framework. This distinguishes between pressures, associated with the achievement of human well-being, and stressors, which are defined as the negative effect of excessive pressures or combination thereof on aquatic ecosystems. Guidelines usually specify threshold values to classify water bodies as appropriate for certain utilitarian uses. However, only few guidelines focus on freshwater ecosystem health. Eight guidelines for monitoring of freshwater ecosystem health were analysed in the UNEP-funded project “International Water Quality Guidelines for Ecosystems”. Based on this review, general benchmark values are proposed for key physico-chemical indicators. Furthermore, adaptive pathways towards improved monitoring and protection of the health of freshwater ecosystems are recommended. In this paper, we review the main findings of the report and also review its recent uptake. Water quality guidelines for freshwater ecosystems cannot be conceived without societal consensus and vision. Different climatic, geographical and socioeconomic contexts are to be considered too. Their development is embedded in an adaptive cycle. Its multiple phases and steps indicate a long-term approach including reassessment and potential revisions.

Screening of microalgae liquid extracts for their bio stimulant properties on plant growth, nutrient uptake and metabolite profile of Solanum lycopersicum L

The present study investigates the biostimulant effects of 18 Crude Bio-Extracts (CBEs) obtained from Microalgae and Cyanobacteria on tomato plant growth, chlorophyll content, nutrient uptake and metabolite profile. Significant root and shoot length improvement (112.65%, 53.70%); was recorded at treatment with Aphanothece sp and C. ellipsoidea CBEs respectively. Meanwhile, the highest root and shoot dry weight (DW) (34.81%, 58.69%) were obtained at treatment with Aphanothece sp. The latter also displayed the maximum uptake of Nitrogen, phosphorus and potassium, which increased by 185.17%, 119.36% and 78.04% respectively compared with non-treated plants. Principal Component Analysis (PCA) confirmed that Phosphorus and Potassium levels in roots were closely related to enhanced Root length, whereas Nitrogen and chlorophyll b were closely related to Shoot and root DW. Additionally, Gas Chromatography-mass spectrometry (GC-MS) indicated that treatment with CBEs, induced the production of a vast array of metabolites. Treated plants recorded higher accumulation of palmitic and stearic acids, which could indicate a stimulation in de novo Lipid synthesis. CBEs also triggered the accumulation of pyridine-3-carboxamide (an amide active form of vitamin B3) and Linolenic acid; one of the key precursors in the biosynthetic pathway leading to plant jasmonates. Our results are a first step towards understanding the effects of microalgal extracts on plant physiology and biochemical pathways. Further investigations on biochemical fractionation of microalgal extracts and agronomic tests of their purified bioactive compounds could be a useful principal novelty for in-depth study of CBE action mechanisms. Other useful tools include; Comparative hormone profiling of treated and non-treated plants accompanied with combined High-Throughput Plant Phenotyping, transcriptomics and metabolomics analysis.

Sustainable Water Resources Management: A Bibliometric Overview

While global water demand continues increasing, the quantity and quality of water resources is decreasing in many regions. Conflicts over competition in the use of water are likely to increase as societies face social, economic and political challenges, especially aggravated by climate change. In this scenario, sustainable management of water resources is a key priority to meet the growing demand for water and to achieve a safe and environmentally sustainable future supply. The main objective of this article was to show an image of the international scientific production related to “Sustainable Water Resources Management” by using the comparative bibliometric study of the documents indexed in the WoS(Web of Science) and Scopus databases as a tool; and to analyze relevant aspects such as their coverage, correlation, overlap, growth, citation, dispersion or concentration, among others. For this purpose, and by means of an advanced search of terms, a representative set of 160 articles in WoS and 210 in Scopus were selected (with a time limit that limited the results to anything published before 2017, including 2017), which form the ad-hoc basis of the analysis. Their significant increase in both the number of articles and citations received in the last 10 years demonstrates the growing interest of the scientific community in its study. Regarding the analysis of the databases, although WoS and Scopus differ in terms of scope, volume of data and coverage policies, both information systems are complementary and non-exclusive. Despite their similarities, Scopus performs better coverage in the specific area of Sustainable Water Resource Management by collecting a greater number of articles and receiving a greater number of citations.

Drag Effect of Water Consumption on Urbanization—A Case Study of the Yangtze River Economic Belt from 2000 to 2015

Urbanization is an engine of economic development, but this process is often constrained by increasingly scarce water resources. A model predicting the drag effect of water consumption on urbanization would be useful for future planning for sustainable water resource utilization and economic growth. Using panel data from 11 provinces in China’s Yangtze River economic belt (YREB) from 2000 to 2015, we apply Romer’s growth drag theory with spatial econometric models to quantitatively analyze the drag effect of water consumption on urbanization. The results show the following. (1) The drag effect of water consumption on urbanization has significant spatial correlation; the spatial Durbin model is the best model to calculate this spatial connection. (2) The spatial coefficient is 0.39 and the drag that is caused by water consumption on urbanization in the YREB is 0.574, which means that when spatial influences are considered, urbanization speed slows by 0.574% due to water consumption constraints. (3) Each region in the YREB has different water consumption patterns and structure; we further calculate each region’s water consumption drag on urbanization. We find that areas with high urbanization levels, like Shanghai (average 84.7%), have a lower water consumption drag effect (0.227), and they can avoid the “resource curse” of water resource constraints. However, some low-level urbanization provinces, like Anhui (average 39.3%), have a higher water consumption drag effect (1.352). (4) Our results indicate that the water drag effect is even greater than the drag effect of coal and land. Therefore, policies to increase urbanization should carefully consider the way that water constraints may limit growth. Likewise, our spatial model indicates that policy makers should work with neighboring provinces and construct an effective regional water cooperation mechanism.

A risk assessment approach to manage inundation of Elseya albagula nests in impounded waters: a win-win situation?

A risk assessment process was used to trial the impact of potential new operating rules on the frequency of nest inundation for the White-throated snapping turtle, Elseya albagula, in the impounded waters of the Burnett River, Queensland, Australia. The proposed operating rules would increase the barrage storage level during the turtle nesting season (May-July) and then would be allowed to reduce to a lower level for incubation for the rest of the year. These proposed operating rules reduce rates of nest inundation by altering water levels in the Ben Anderson Barrage impoundment of the Burnett River. The rules operate throughout the turtle reproductive period and concomitantly improve stability of littoral habitat and fishway operation. Additionally, the proposed rules are expected to have positive socio-economic benefits within the region. While regulated water resources will inherently have a number of negative environmental implications, these potential new operating rules have the capacity to benefit the environment while managing resources in a more sustainable manner. The operating rules have now been enacted in subordinate legislation and require the operator to maintain water levels to minimize turtle nest inundation.

Planetary boundaries: Guiding human development on a changing planet

The planetary boundary (PB) concept, introduced in 2009, aimed to define the environmental limits within which humanity can safely operate. This approach has proved influential in global sustainability policy development. Steffen et al. provide an updated and extended analysis of the PB framework. Of the original nine proposed boundaries, they identify three (including climate change) that might push the Earth system into a new state if crossed and that also have a pervasive influence on the remaining boundaries. They also develop the PB framework so that it can be applied usefully in a regional context.

Science , this issue 10.1126/science.1259855

Evaluating Collaborative Institutions in Context: The Case of Regional Water Management in Southern California

Regional collaborative institutions are seen as tools for improving collaboration and for reducing the inefficiency of fragmented management and planning. However, recent research has shown that the ability of new regional institutions to achieve these aims is contingent upon their relationship to the existing institutional landscape. This paper uses network analyses of six newly created Integrated Regional Water Management (IRWM) subregions in southern California to examine how their introduction intersects existing water management systems and whether the patterns of interaction in water planning have changed as a result. The results further our understanding of collaborative governance and regionalism by showing that the ability of regional institutions to facilitate new interactions can vary widely across a given institutional landscape. Further, while IRWM has helped to strengthen the water management network in southern California, it has not replaced existing watershed planning efforts. Interviews with water managers reveal there is support for IRWM but it is still too early to evaluate its effectiveness. Further research should explore the drivers and consequences of heterogeneity in IRWM and whether the incentives for participation are sufficient.

Systemic solutions for multi-benefit water and environmental management

The environmental and financial costs of inputs to, and unintended consequences arising from narrow consideration of outputs from, water and environmental management technologies highlight the need for low-input solutions that optimise outcomes across multiple ecosystem services. Case studies examining the inputs and outputs associated with several ecosystem-based water and environmental management technologies reveal a range from those that differ little from conventional electro-mechanical engineering techniques through methods, such as integrated constructed wetlands (ICWs), designed explicitly as low-input systems optimising ecosystem service outcomes. All techniques present opportunities for further optimisation of outputs, and hence for greater cumulative public value. We define 'systemic solutions' as "…low-input technologies using natural processes to optimise benefits across the spectrum of ecosystem services and their beneficiaries". They contribute to sustainable development by averting unintended negative impacts and optimising benefits to all ecosystem service beneficiaries, increasing net economic value. Legacy legislation addressing issues in a fragmented way, associated 'ring-fenced' budgets and established management assumptions represent obstacles to implementing 'systemic solutions'. However, flexible implementation of legacy regulations recognising their primary purpose, rather than slavish adherence to detailed sub-clauses, may achieve greater overall public benefit through optimisation of outcomes across ecosystem services. Systemic solutions are not a panacea if applied merely as 'downstream' fixes, but are part of, and a means to accelerate, broader culture change towards more sustainable practice. This necessarily entails connecting a wider network of interests in the formulation and design of mutually-beneficial systemic solutions, including for example spatial planners, engineers, regulators, managers, farming and other businesses, and researchers working on ways to quantify and optimise delivery of ecosystem services.

River networks as biodiversity hotlines

For several years, measures to insure healthy river functions and to protect biodiversity have focused on management at the scale of drainage basins. Indeed, rivers bear witness to the health of their drainage basins, which justifies integrated basin management. However, this vision should not mask two other aspects of the protection of aquatic and riparian biodiversity as well as services provided by rivers. First, although largely depending on the ecological properties of the surrounding terrestrial environment, rivers are ecological systems by themselves, characterized by their linearity: they are organized in connected networks, complex and ever changing, open to the sea. Second, the structure and functions of river networks respond to manipulations of their hydrology, and are particularly vulnerable to climatic variations. Whatever the scale considered, river networks represent "hotlines" for sharing water between ecological and societal systems, as well as for preserving both systems in the face of global change. River hotlines are characterized by spatial as well as temporal legacies: every human impact to a river network may be transmitted far downstream from its point of origin, and may produce effects only after a more or less prolonged latency period. Here, I review some of the current issues of river ecology in light of the linear character of river networks.

Human freshwater demand for economic activity and ecosystems in Taiwan

Freshwater is necessary to economic activity, and humans depend on goods and services generated by water-dependent ecosystems. However, national freshwater management usually focuses on direct use of domestic freshwater. With an increasing scarcity of freshwater, attention has turned to two indirect uses of freshwater by humans. The first indirect use is freshwater used by foreign countries when producing products for export. The second use is freshwater required by local ecosystems: human survival and development depend on goods and services generated in these ecosystems. This work adopted Taiwan as a case study. In addition to two widely recognized ecosystem freshwater demands, evapotranspiration and reversed river flow, this study suggests that freshwater is a constituent of some abiotic components, such as groundwater in aquifers, because excessive withdrawal has already caused significant land subsidence in Taiwan. Moreover, the estimated results show that Taiwan's net imports of freshwater through trade amounts to approximately 25% of its total freshwater use for economic production. Integrating industrial policy, trade policy, and national freshwater management is a useful approach for developing strategies to limit the growing use of freshwater in Taiwan. Policy implications are then developed by further analyzing withdrawal sources of freshwater (domestic and foreign) for supporting economic production in Taiwan and identifying the factors (domestic final demand and export) driving freshwater-intensive products.

Improvement of water use efficiency in rice by expression of HARDY, an Arabidopsis drought and salt tolerance gene

Freshwater is a limited and dwindling global resource; therefore, efficient water use is required for food crops that have high water demands, such as rice, or for the production of sustainable energy biomass. We show here that expression of the Arabidopsis HARDY (HRD) gene in rice improves water use efficiency, the ratio of biomass produced to the water used, by enhancing photosynthetic assimilation and reducing transpiration. These drought-tolerant, low-water-consuming rice plants exhibit increased shoot biomass under well irrigated conditions and an adaptive increase in root biomass under drought stress. The HRD gene, an AP2/ERF-like transcription factor, identified by a gain-of-function Arabidopsis mutant hrd-D having roots with enhanced strength, branching, and cortical cells, exhibits drought resistance and salt tolerance, accompanied by an enhancement in the expression of abiotic stress associated genes. HRD overexpression in Arabidopsis produces thicker leaves with more chloroplast-bearing mesophyll cells, and in rice, there is an increase in leaf biomass and bundle sheath cells that probably contributes to the enhanced photosynthesis assimilation and efficiency. The results exemplify application of a gene identified from the model plant Arabidopsis for the improvement of water use efficiency coincident with drought resistance in the crop plant rice.

The science and practice of environmental flows and the role of hydrogeologists

Conflicts between ecosystems and human needs for fresh water are increasing. The purpose of this paper is to raise awareness in the hydrogeologic community of environmental flows (EFs) and to address the major challenges involved in their protection. Ground water is a key component of EFs, and therefore hydrogeologists are called upon to get involved in the ongoing debates about maintaining healthy riverine ecosystems. Promising opportunities for achieving EFs in both underallocated and overallocated basins as well as new methods for protecting fresh water ecosystems developed in different countries are outlined. EF protection measures include private water trusts, "upside-down instream flow water rights," the "public trust" doctrine, and water markets, among other measures. A number of knowledge gaps are identified, to which hydrogeologists could contribute, such as our rudimentary knowledge about ground water-dependent ecosystems, aspects of stream-aquifer interactions, and the impacts of land-use changes. The values that society places on the different uses of water ultimately determine where the water is allocated. EF requirements can be legitimately recognized and addressed by basing the environmental needs of hydrologic systems on robust science, focusing on increasing the productivity of water use, engaging society in understanding the benefits and costs of decisions that affect ecosystems, and taking advantage of various opportunities for achieving EF goals.

Freshwater biodiversity: importance, threats, status and conservation challenges

Freshwater biodiversity is the over-riding conservation priority during the International Decade for Action - 'Water for Life' - 2005 to 2015. Fresh water makes up only 0.01% of the World's water and approximately 0.8% of the Earth's surface, yet this tiny fraction of global water supports at least 100000 species out of approximately 1.8 million - almost 6% of all described species. Inland waters and freshwater biodiversity constitute a valuable natural resource, in economic, cultural, aesthetic, scientific and educational terms. Their conservation and management are critical to the interests of all humans, nations and governments. Yet this precious heritage is in crisis. Fresh waters are experiencing declines in biodiversity far greater than those in the most affected terrestrial ecosystems, and if trends in human demands for water remain unaltered and species losses continue at current rates, the opportunity to conserve much of the remaining biodiversity in fresh water will vanish before the 'Water for Life' decade ends in 2015. Why is this so, and what is being done about it? This article explores the special features of freshwater habitats and the biodiversity they support that makes them especially vulnerable to human activities. We document threats to global freshwater biodiversity under five headings: overexploitation; water pollution; flow modification; destruction or degradation of habitat; and invasion by exotic species. Their combined and interacting influences have resulted in population declines and range reduction of freshwater biodiversity worldwide. Conservation of biodiversity is complicated by the landscape position of rivers and wetlands as 'receivers' of land-use effluents, and the problems posed by endemism and thus non-substitutability. In addition, in many parts of the world, fresh water is subject to severe competition among multiple human stakeholders. Protection of freshwater biodiversity is perhaps the ultimate conservation challenge because it is influenced by the upstream drainage network, the surrounding land, the riparian zone, and - in the case of migrating aquatic fauna - downstream reaches. Such prerequisites are hardly ever met. Immediate action is needed where opportunities exist to set aside intact lake and river ecosystems within large protected areas. For most of the global land surface, trade-offs between conservation of freshwater biodiversity and human use of ecosystem goods and services are necessary. We advocate continuing attempts to check species loss but, in many situations, urge adoption of a compromise position of management for biodiversity conservation, ecosystem functioning and resilience, and human livelihoods in order to provide a viable long-term basis for freshwater conservation. Recognition of this need will require adoption of a new paradigm for biodiversity protection and freshwater ecosystem management - one that has been appropriately termed 'reconciliation ecology'.

Freshwater for resilience: a shift in thinking

Humanity shapes freshwater flows and biosphere dynamics from a local to a global scale. Successful management of target resources in the short term tends to alienate the social and economic development process from its ultimate dependence on the life-supporting environment. Freshwater becomes transformed into a resource for optimal management in development, neglecting the multiple functions of freshwater in dynamic landscapes and its fundamental role as the bloodstream of the biosphere. The current tension of these differences in worldview is exemplified through the recent development of modern aquaculture contrasted with examples of catchment-based stewardship of freshwater flows in dynamic landscapes. In particular, the social and institutional dimension of catchment management is highlighted and features of social-ecological systems for resilience building are presented. It is concluded that this broader view of freshwater provides the foundation for hydrosolidarity.

Introduction

Introduction