Water security forms the basis for achieving multi-dimensional poverty alleviation. Water security is necessary for moving toward sustainable development. It reduces poverty and improves quality of life. Achieving water security is increasingly becoming a policy challenge in most of the developing countries like India. Water security is a comprehensive concept that comprises access to quantity and quality for different users and uses, ensuring environmental, economic, and social sustainability in the long run. It needs to be achieved at different scales (i.e., household, regional, and national levels). This calls for an integrated approach incorporating hydrological, socioeconomic, and ecosystem aspects. Water resources accounting is critical for ensuring water security. Resource accounting helps in identifying efficient and optimum allocation of resources to various components of water security. Integrating the costs of strengthening the natural resource base and environmental externalities is likely to help sustaining services in the long run. Integrating the economics of protecting the natural resource base into the planning and designing of service delivery is critical in this regard.
Article
Economics of Water Security in India: Need for Strengthening Natural Capital
V. Ratna Reddy
Article
The Economics of Watershed Management
Brent M. Haddad
Watersheds are physical regions from which all arriving water flows to a single exit point. The shared hydrology means that other biophysical systems are linked, typically with upper-gradient regions influencing lower-gradient ones. This situation frames the challenge of managing economic and other uses of watersheds both in terms of individual activities and their influence on other connected processes and activities. Economics provides concepts and methods that help managers with decision making in the complex physical, biological, and institutional environment of a watershed. Among the important concepts and methods that help characterize watershed processes are externalities, impacts of economic activity that fall upon individuals not party to the activity, and third parties, individuals impacted without consent. Public goods and common pool resources describe categories of things or processes that by their nature are not amenable to regular market transactions. Their regulation requires special consideration and alternative approaches to markets. Benefit-cost analysis and valuation are related methods that provide a means to compare alternative uses of the same system. Each is based on the normative argument that the best use provides the greatest net benefits to society. And intergenerational equity is a value orientation that argues for preservation of watershed processes for the benefit of future generations. The need for effective watershed management methods pushed 20th-century economists to adapt their discipline to the complexity of watersheds, from which emerged subdisciplines of natural resource economics, environmental economics, and ecological economics. The field is still evolving with a growing interest in data gathering through land-based low-cost data collection systems and remote sensing, and in emerging data analysis techniques to improve management decisions.
Article
Ecosystem Management of the Boreal Forest
Timo Kuuluvainen
Boreal countries are rich in forest resources, and for their area, they produce a disproportionally large share of the lumber, pulp, and paper bound for the global market. These countries have long-standing strong traditions in forestry education and institutions, as well as in timber-oriented forest management. However, global change, together with evolving societal values and demands, are challenging traditional forest management approaches. In particular, plantation-type management, where wood is harvested with short cutting cycles relative to the natural time span of stand development, has been criticized. Such management practices create landscapes composed of mosaics of young, even-aged, and structurally homogeneous stands, with scarcity of old trees and deadwood. In contrast, natural forest landscapes are characterized by the presence of old large trees, uneven-aged stand structures, abundant deadwood, and high overall structural diversity. The differences between managed and unmanaged forests result from the fundamental differences in the disturbance regimes of managed versus unmanaged forests. Declines in managed forest biodiversity and structural complexity, combined with rapidly changing climatic conditions, pose a risk to forest health, and hence, to the long-term maintenance of biodiversity and provisioning of important ecosystem goods and services. The application of ecosystem management in boreal forestry calls for a transition from plantation-type forestry toward more diversified management inspired by natural forest structure and dynamics.
Article
Ecosystem Services
Leon C. Braat
The concept of ecosystem services considers the usefulness of nature for human society. The economic importance of nature was described and analyzed in the 18th century, but the term ecosystem services was introduced only in 1981. Since then it has spurred an increasing number of academic publications, international research projects, and policy studies. Now a subject of intense debate in the global scientific community, from the natural to social science domains, it is also used, developed, and customized in policy arenas and considered, if in a still somewhat skeptical and apprehensive way, in the “practice” domain—by nature management agencies, farmers, foresters, and corporate business. This process of bridging evident gaps between ecology and economics, and between nature conservation and economic development, has also been felt in the political arena, including in the United Nations and the European Union (which have placed it at the center of their nature conservation and sustainable use strategies).
The concept involves the utilitarian framing of those functions of nature that are used by humans and considered beneficial to society as economic and social services. In this light, for example, the disappearance of biodiversity directly affects ecosystem functions that underpin critical services for human well-being. More generally, the concept can be defined in this manner: Ecosystem services are the direct and indirect contributions of ecosystems, in interaction with contributions from human society, to human well-being.
The concept underpins four major discussions: (1) Academic: the ecological versus the economic dimensions of the goods and services that flow from ecosystems to the human economy; the challenge of integrating concepts and models across this paradigmatic divide; (2) Social: the risks versus benefits of bringing the utilitarian argument into political debates about nature conservation (Are ecosystem services good or bad for biodiversity and vice versa?); (3) Policy and planning: how to value the benefits from natural capital and ecosystem services (Will this improve decision-making on topics ranging from poverty alleviation via subsidies to farmers to planning of grey with green infrastructure to combining economic growth with nature conservation?); and (4) Practice: Can revenue come from smart management and sustainable use of ecosystems? Are there markets to be discovered and can businesses be created? How do taxes figure in an ecosystem-based economy? The outcomes of these discussions will both help to shape policy and planning of economies at global, national, and regional scales and contribute to the long-term survival and well-being of humanity.
Article
Ecotourism
Giles Jackson
Ecotourism is responsible travel to natural areas that educates and inspires through interpretation—increasingly paired with practical action—that helps conserve the environment and sustain the well-being of local people. Ecotourism is the fastest-growing segment of the travel and tourism industry, and its economic value is projected to exceed USD$100 billion by 2027. Ecotourism emerged in the 1960s as a response to the destructive effects of mass tourism and has been embraced by an increasing number of governments, especially in the developing world, as a vehicle for achieving the UN Sustainable Development Goals. As an emerging, interdisciplinary field of study, ecotourism has reached a critical inflection point, as scholars reflect on the achievements and shortcomings of several decades of research and set out the research agenda for decades to come. The field has yet to achieve consensus on the most basic questions, such as how ecotourism is, or should be, defined; what makes it different from nature-based and related forms of tourism; and what factors ultimately determine the success or failure of ecotourism as a vehicle for sustainable development. This lack of consensus stems in part from the different perspectives and agendas within and between the academic, policy, and industry communities. Because it is based on measured and observed phenomena, empirical research has a critical role to play in advancing the theory and practice of ecotourism. However, scholars also recognize that to fulfill this role, methodologies must evolve to become more longitudinal, scalable, inclusive, integrative, and actionable.
Article
Emerging Issues and Challenges in Transboundary Freshwater: The Role of Treaties and Treaty Design
Shlomi Dinar
Freshwater’s transboundary nature (in the form of rivers, lakes, and underground aquifers) means that it ties countries (or riparians) in a web of interdependence. Combined with water scarcity and increased water variability, and the sheer necessity of water for survival and national development, these interdependencies may often lead to conflict. While such conflict is rarely violent in nature, political conflict over water is quite common as states diverge over how to share water or whether to develop a joint river for hydropower, say, or to use the water for agriculture.
For the same reasons that water may be a source of conflict, it is also a source of cooperation. In fact, if the number of documented international agreements over shared water resources is any indication, then water’s cooperative history is a rich one. As the most important and accepted tools for formalizing inter-state cooperation, treaties have become the focus of research and analysis. While treaties do not necessarily guarantee cooperation, they do provide states with a platform for dealing with conflict as well as the means to create benefits for sustained cooperation. This also suggests that the way treaties are designed—in other words, what mechanisms and instruments are included in the agreement—is likewise relevant to analyzing conflict and cooperation.
Article
Emerging Issues in Groundwater Sustainability: New Challenges
Encarna Esteban
The increased pressure on groundwater has resulted in a major deterioration of the overall status of this resource. Despite efforts to control the degradation of underground water bodies, most aquifers worldwide experience serious quality and quantity problems. New emerging issues around groundwater resources have become relevant and pose additional protection and management challenges. Climate change, with predictable impacts on temperature and precipitation, will cause considerable fluctuations in aquifer recharge levels and subsequent problems in the status of these water bodies. Expected reductions in water availability will increase groundwater withdrawals not just for irrigation but also for urban and industrial water use. Declines in stored water will have an impact on many freshwater ecosystems whose survival depends on the status of groundwater bodies. Furthermore, land subsidence, as a side effect of aquifer overexploitation, involves land collapse and deformation that are especially harmful for urban areas and deteriorate physical and hydrological water systems. All these new challenges require integrated planning strategies and multisectorial solutions to curtail the deterioration of these resources. Although these issues have been studied, in-depth analyses of the economic, social, and policy implications of groundwater management strategies are still necessary.
Article
From Flood Control to Flood Adaptation
Katharine J. Mach, Miyuki Hino, A.R. Siders, Steven F. Koller, Caroline M. Kraan, Jennifer Niemann, and Brett F. Sanders
Societies throughout the world are experiencing more severe and frequent flooding with consequences for people’s livelihoods, health, safety, and heritage. Much flood risk management to date has aimed to maximize economic benefits, reduce the likelihood of flood disasters, and facilitate recovery where needed. It has assumed a stationary climate and focused on extremes and financial losses. But this paradigm of flood control is increasingly at odds with the full set of challenges and requirements for flood risk management.
Critical challenges motivate a shift from flood control to flood adaptation. First, under climate change, flood risks are intensifying and changing, and new normals are appearing, such as daily high-tide flooding or permanent inundation. Fully controlling flood hazards with one-time interventions is increasingly untenable. Second, floods affect numerous, multidimensional aspects of human and ecological well-being and social justice. Past flood control efforts, and the decision-making processes that produced them, have often failed to address these multidimensional concerns or even had negative side effects. Fundamental adjustments are emerging and will be needed: a guiding paradigm of flexibility rather than control, a system-wide approach with coordinated action across scales, and increased attention to the full range of priorities relevant to successful interventions.
For example, science and research for flood risk adaptation increasingly involve processes supporting usable, inclusive knowledge tailored to decision contexts. Integrative science partnerships such as collaborative flood modeling can incorporate the dynamic physical and social landscapes of flood drivers, impacts, and management. Flexible processes allow updating as flood risks change, and collaborative processes can build intuition, trust, and understanding of risks, including improved awareness of the values and relationships that are threatened and preferred response options. The goal of flood risk management is no longer limited to preventing floods; flood risk management must balance risk tolerances with ecological and social benefits and weigh the trade-offs of management strategies against other societal goals. This “science for society” is inherently political, requiring careful attention to and evaluation of who participates, whose goals are prioritized, and who benefits.
Furthermore, methods of evidence-based decision-making must be able to accommodate deep uncertainties, changing risks and values, and limits to responses. Shifts are already occurring, including dynamic adaptive management practices and improvements to tools such as cost–benefit comparisons. These changes illustrate a larger reframing within flood risk management, away from disaster management focused on extreme isolated events and toward adaptation in response to enduring changes across both extreme and average conditions.
The current challenges of flood risk management create opportunities for integrating lessons from diverse domains of actionable science and public policy and thereby innovating processes of climate adaptation relevant to a range of climate risks.
Article
Statistical Scaling of Randomly Fluctuating Hierarchical Variables
Shlomo P. Neuman, Monica Riva, Alberto Guadagnini, Martina Siena, and Chiara Recalcati
Environmental variables tend to fluctuate randomly and exhibit multiscale structures in space and time. Whereas random fluctuations arise from variations in environmental properties and phenomena, multiscale behavior implies that these properties and phenomena possess hierarchical structures. Understanding and quantifying such random, multiscale behavior is critical for the analysis of fluid flow as well as mass and energy transport in the environment.
The multiscale nature of randomly fluctuating variables that characterize a hierarchical environment (or process) tends to be reflected in the way their increments vary in space (or time). Quite often such increments (a) fluctuate randomly in a highly irregular fashion; (b) possess symmetric, non-Gaussian frequency distributions characterized by heavy tails, which sometimes decay with separation distance or lag; (c) exhibit nonlinear power-law scaling of sample structure functions (statistical moments of absolute increments) in a midrange of lags, with breakdown in such scaling at small and large lags; (d) show extended power-law scaling (linear relations between log structure functions of successive orders) at all lags; (e) display nonlinear scaling of power-law exponent with order of sample structure function; and (f) reveal various degrees of anisotropy in these behaviors. Similar statistical scaling is known to characterize many earth, ecological, biological, physical, astrophysical, and financial variables.
The literature has traditionally associated statistical scaling behaviors of the aforementioned kind with multifractals. This is so even though multifractal theory (a) focuses solely on statistical scaling of variable increments, unrelated to statistics of the variable itself, and (b) explains neither observed breakdown in power-law scaling at small and large lags nor extended power-law scaling of such increments. A novel Generalized sub-Gaussian scaling model is introduced that does not suffer from such deficiencies, and some of its key aspects are illustrated on microscale surface measurements of a calcite crystal fragment undergoing dissolution reaction due to contact with a fluid solution.
Article
The Global Groundwater Revolution
Jac van der Gun
Human behavior in relation to groundwater has remained relatively unchanged from ancient times until the early 20th century. Intercepting water from springs or exploiting shallow aquifers by means of wells or qanats was common practice worldwide, but only modest quantities of groundwater were abstracted. In general, the resource was taken for granted in absence of any knowledge regarding groundwater systems and their vulnerability. During the 20th century, however, an unprecedent change started spreading globally—a change so drastic that it could be called the Global Groundwater Revolution. It did not surface simultaneously everywhere but rather encroached into different regions as waves of change, with varied timing, depending on local conditions. This Global Groundwater Revolution has three main components: (1) rapid intensification of the exploitation of groundwater, (2) fundamentally changing views on groundwater, and (3) the emergence of integrated groundwater management and governance. These three components are mostly interdependent, although their emergence and development tend to be somewhat asynchronous. The Global Groundwater Revolution marks a radical historical change in the relation between human society and groundwater. It has taken benefits produced by groundwater to an unprecedented level, but their sustainability is assured only if there is good groundwater governance.
Article
Green Infrastructure for Stormwater Runoff Control in China
Haifeng Jia and Dingkun Yin
In the early 21st century, high-intensity human activities have led to the rapid development and expansion of urban areas in many countries, and these have had several adverse impacts upon the water environment. In particular, urban runoff quantity and quality control have emerged as key concerns for municipal officials. China, as one of the countries with rapid urbanization, faces many challenges in this process. Since the year 2000, China has been promoting the protection of its urban water environment using ecological construction. Use of green infrastructure (GI) to solve urban stormwater issues have become the priority of urban green and sustainable development. The Sponge City (SPC) approach was proposed to emphasize the comprehensive construction of multi-objective stormwater drainage and flood mitigation systems, and to consider water ecology, public safety, environmental protection, and preservation of water resources. The goal of GI is to achieve storm runoff quality enhancement and pollution control, which is similar to the sustainable development concept of SPC. According to its major functions, GI can be divided into infiltration and retention GI, regulation GI, transmission GI, pollution interception and treatment GI. GI should be planned and designed according to the long-term runoff volume capture ratio, which is determined by the annual rainfall depth and the level of catchment development at the project site. Different structural layer materials and spatial layout of GI have significant impact on their effects. Upon the completion of a project, long-term monitoring is recommended for evaluating its effectiveness. In order to ensure the continuous efficiency of GI, it is necessary to carry out regular maintenance. Different types of GI demand various maintenance methods and frequencies. Appropriate maintenance methods can effectively extend the service life of GI.
Article
Groundwater Development Paths in the U.S. High Plains
Renata Rimšaitė and Nicholas Brozović
The High Plains Aquifer is the largest aquifer in the United States and the major source of groundwater withdrawals in the region. Although regionally abundant, groundwater availability for agriculture and other uses is not uniform across the area. Three separate states comprising the most significant portion of the aquifer have distinct climate and hydrologic characteristics, water law systems, and institutional groundwater governance leading to different concerns about water policy issues across the area.
The northern, largest, and most saturated part of the High Plains Aquifer is located under Nebraska. The state has the largest irrigated area in the United States, most of which is groundwater irrigated. Nebraska is the home of the largest companies in the center pivot irrigation industry. Center pivot technology has had a fundamental role in expanding groundwater-fed irrigation. Nebraska is not free from groundwater depletion issues, but these issues are more important in central and south-central parts of the aquifer underlying large, primarily agricultural, lands of Kansas and Texas. The natural aquifer recharge is much lower in the south-central parts of the region, which has caused large groundwater extractions to have more significant water declines than in Nebraska.
In the United States, the greatest portion of water quantity management regulatory oversight is left to individual states and local government agencies. Each of the three states has a unique legal system, which highly influences the framework of groundwater management locally. In Nebraska, groundwater is governed following two doctrines: correlative and reasonable use, which, in times of water shortage, lead to a proportional reduction of everyone’s allocation. Kansas uses the prior appropriation doctrine to manage groundwater, which applies the seniority principle when there is scarcity in water availability, making junior water rights holders bear the greatest risk. The absolute ownership doctrine is used to govern groundwater in Texas, which allows landowners to drill wells on their property and extract as much water as needed.
Institutional groundwater governance in Nebraska is performed by the system of 23 locally elected Natural Resources Districts having full regulatory power to manage the state’s groundwater. The local governments use a variety of regulatory and incentive-based groundwater management tools to achieve local groundwater management goals. In Kansas, the Chief Engineer in the Kansas Department of Agriculture is in charge of water administration for the state. The Kansas legislature established five Groundwater Management Districts to address groundwater depletion issues, which can make policy recommendations but do not have the power to regulate. Groundwater Conservation Districts were created in Texas to provide protection from uncontrolled water mining in the state. The districts gained more power to regulate and enforce rules over time; however, significant groundwater depletion issues remain.
Multiple lessons have been learned across the region since the beginning of groundwater development. Some of these could be applied in other areas seeking to address negative consequences of groundwater use. Forward-looking perspectives about groundwater management in the region vary from strong government-led solutions in Nebraska to various producer-initiated innovative approaches in Kansas and Texas.
Article
Hedging and Financial Tools for Water Management
C. Dionisio Pérez-Blanco
The management of risky water episodes entails a comprehensive set of instruments that can be broadly divided into two groups: damage prevention and damage management. Damage prevention instruments aim at negating or minimizing the economic damage of water scarcity and water extremes, and they include hard and soft engineering, information and awareness campaigns, and regulations and economic incentives. Damage management instruments aim at compensating damages and facilitating recovery, and they include tort law and hedging and financial tools. The growing interconnections and cascading uncertainties across coupled human and water systems make it increasingly challenging to comprehensively predict and anticipate expected damages from water scarcity and extremes, which is giving higher prominence to the management of damages, notably through hedging and financial tools. Hedging and financial tools are a risk transfer mechanism by which a potential future damage is transferred from one party to another, typically in exchange of a pecuniary compensation (risk premium), albeit they can be also freely provided (e.g., state aid). Hedging and financial instruments are varied and include futures, options, insurance, self-capitalization, reinsurance, private actions such as charities or nongovernmental organizations, state aid, and solidarity funds.
The first section of this document discusses the political context for disaster risk reduction efforts at an international level and provides key definitions. The second section presents a taxonomy for hedging and financial instruments; assesses their strengths and weaknesses, performance, and market penetration levels; and critically reviews reform propositions in the literature toward increasing their performance and adoption. The third section discusses the interconnections between hedging and financial tools and damage prevention tools, as well as how their design can enhance each other’s performance. The last section discusses barriers and enablers for the adoption of hedging and financial tools.
Article
Hydroeconomics
Manuel Pulido-Velazquez and Amaury Tilmant
The management of water resources systems involves influencing and improving the interaction among three subsystems: natural (biophysical), economic, and legal-institutional frameworks. In this sense, hydroeconomic models have the advantage of analyzing water management problems through models that explicitly represent these interactions. The combination of economic, engineering, and environmental aspects of management provides better-informed results for decision making in the complex environment in which water management operates.
Hydroeconomic models (HEMs) are spatially distributed management models of a river basin or system in which both water supply and demands are economically and hydrologically characterized. This definition is sometimes relaxed to refer in general to water resources management models that include the economic component. In HEMs, the management and allocation of water is either driven by the economic value of water or economically assessed, which contributes to policy analysis and reveals opportunities for better economic management. The traditional view of water demand as a fixed requirement to be satisfied is modified by a view of demand that adapts to the changes in the scarcity of water. The integration of economics in HEMs allows the identification of the best combination of water supply and demand management options within a consistent framework. As water scarcity increases worldwide, water managers will increasingly turn to tools that reveal solutions to increase efficiency in water use, fostering improved economic development through better-informed policy choices.
Article
Impacts of Megacities on Air Quality: Challenges and Opportunities
Luisa T. Molina, Tong Zhu, Wei Wan, and Bhola R. Gurjar
Megacities (metropolitan areas with populations over 10 million) and large urban centers present a major challenge for the global environment. Transportation, industrial activities, and energy demand have increased in megacities due to population growth and unsustainable urban development, leading to increasing levels of air pollution that subject the residents to the health risks associated with harmful pollutants, and impose heavy economic and social costs. Although much progress has been made in reducing air pollution in developed and some developing world megacities, there are many remaining challenges in achieving cleaner and breathable air for their residents. As centers of economic growth, scientific advancement, and technology innovation, however, these urban settings also offer unique opportunities to capitalize on the multiple benefits that can be achieved by optimizing energy use, reducing atmospheric pollution, minimizing greenhouse gas emissions, and bringing many social benefits. Realizing such benefits will, however, require strong and wide-ranging institutional cooperation, public awareness, and multi-stakeholder involvement. This is especially critical as the phenomenon of urbanization continues in virtually all countries of the world, and more megacities will be added to the world, with the majority of them located in developing countries.
The air quality and emission mitigation strategies of eight megacities—Mexico City, Beijing, Shanghai, Shenzhen, Chengdu, Delhi, Kolkata, and Mumbai—are presented as examples of the environmental challenges experienced by large urban centers. While these megacities share common problems of air pollution due to the rapid growth in population and urbanization, each city has its own unique circumstances—geographical location, meteorology, sources of emissions, human and financial resources, and institutional capacity—to address them. Nevertheless, the need for an integrated multidisciplinary approach to air quality management is the same.
Mexico City’s air pollution problem was considered among the worst in the world in the 1980s due to rapid population growth, uncontrolled urban development, and energy consumption. After three decades of implementing successive comprehensive air quality management programs that combined regulatory actions with technological change and were based on scientific, technical, social, and political considerations, Mexico City has made significant progress in improving its air quality; however, ozone and particulate matter are still at levels above the respective Mexican air quality standards. Beijing, Shanghai, Shenzhen, and Chengdu are microcosms of megacities in the People’s Republic of China, with rapid socioeconomic development, expanding urbanization, and swift industrialization since the era of reform and opening up began in the late 1970s, leading to severe air pollution. In 2013, the Chinese government issued the Action Plan for Air Pollution Prevention and Control. Through scientific research and regional coordinated air pollution control actions implemented by the Chinese government authority, the concentration of atmospheric pollutants in several major cities has decreased substantially. About 20% of total megacities’ populations in the world reside in Indian megacities; the population is projected to increase, with Delhi becoming the largest megacity by 2030. The increased demands of energy and transportation, as well as other sources such as biomass burning, have led to severe air pollution. The air quality trends for some pollutants have reduced as a result of emissions control measures implemented by the Indian government; however, the level of particulate matter is still higher than the national standards and is one of the leading causes of premature deaths.
The examples of the eight cities illustrate that although most air pollution problems are caused by local or regional sources of emissions, air pollutants are transported from state to state and across international borders; therefore, international coordination and collaboration should be strongly encouraged. Based on the available technical-scientific information, the regulations, standards, and policies for the reduction of polluting emissions can be formulated and implemented, which combined with adequate surveillance, enforcement, and compliance, would lead to progressive air quality improvement that benefits the population and the environment. The experience and the lessons learned from the eight megacities can be valuable for other large urban centers confronting similar air pollution challenges.
Article
Institutional Fit in the Water Sector
Cathy Rubiños and Maria Bernedo Del Carpio
Adequate water governance is necessary for the world’s sustainability. Because of its importance, a growing literature has studied ways to improve water governance, beginning in the early 2000s. Institutions, which refer to the set of shared rules, codes, and prescriptions that regulate human actions, are a particularly important element of sustainable water governance. Evidence shows that to design institutions that will generate sustainable economic, ecological, and cultural development, it is necessary to consider ecosystems and socioeconomic-cultural systems as social-ecological systems (SESs). In the past, practitioners and international agencies tried to find the government-led panaceas, but this search has been largely unsuccessful. Current views support efforts to move towards addressing complexity (e.g., Integrated Water Resources Management), and search for the fit between the institutional arrangements and SESs’ attributes.
The literature on institutional fit in SESs encourages planners to design institutions by carefully considering the defining features of the problems they are meant to address and the SES context in which they are found. This literature has been developing since the 1990s and has identified different types of misfits. A comprehensive fitness typology that includes all the different types of fitness (ecological, social, SES, and intra-institutional fit) helps organize existing and future work on institutional fit and provides a checklist for governments to be used in the problem-solving process for increasing fitness. The water governance and institutional fitness literature provide examples of management practices and mechanisms for increasing institutional fit for each fitness type. Future research should focus on improving the methodologies to measure different types of fit and testing the effect of introducing fit on SES outcomes.
Article
Interface Urban Forest Management in an Urbanizing Landscape
Maria A. Cunha-e-Sá and Sofia F. Franco
Although forests located near urban areas are a small fraction of the forest cover, a good understanding of the extent to which —wildland-urban interface (WUI) forest conversion affects local economies and environmental services can help policy-makers harmonize urban development and environmental preservation at this interface, with positive impact on the welfare of local communities. A growing part of the forest resource worldwide has come under urban influence, both directly (i.e., becoming incorporated into the interface or located at the interface with urban areas) and indirectly (as urban uses and values have come to dominate more remote forest areas). Yet forestry has been rather hesitant to recognize its urban mandate. Even if the decision to convert land at the WUI (agriculture, fruit, timber, or rural use) into an alternative use (residential and commercial development) is conditional on the relative magnitude and timing of the returns of alternative land uses, urban forestry is still firmly rooted in the same basic concepts of traditional forestry. This in turn neglects features characterizing this type of forestland, such as the urban influences from increasingly land-consumptive development patterns. Moreover, interface timber production-allocated land provides public goods that otherwise would be permanently lost if land were converted to an irreversible use. Any framework discussing WUI optimal rotation periods and conversion dates should then incorporate the urban dimension in the forester problem. It must reflect the factors that influence both urban and forestry uses and account for the fact that some types of land use conversion are irreversible.
The goal is to present a framework that serves as a first step in explaining the trends in the use and management of private land for timber production in an urbanizing environment. Our framework integrates different land uses to understand two questions: given that most of the WUI land use change is irreversible and forestry at this interface differs from classic forestry, how does urban forestry build upon and benefit from traditional forestry concepts and approaches? In particular, what are the implications for the Faustmann harvesting strategy when conversion to an irreversible land use occurs at some point in the future?
The article begins with a short background on the worldwide trend of forestland conversion at the WUI, focusing mostly on the case of developed countries. This provides a context for the theoretical framework used in the subsequent analysis of how urban factors affect regeneration and conversion dates. The article further reviews theoretical models of forest management practices that have considered either land sale following clear-cutting or a switch to a more profitable alternative land use without selling the land. A brief discussion on the studies with a generalization of the classic Faustmann formula for land expectation value is also included. For completeness, comparative statics results and a numerical illustration of the main findings from the private landowner framework are included.
Article
Machine Learning Tools for Water Resources Modeling and Management
Giorgio Guariso and Matteo Sangiorgio
The pervasive diffusion of information and communication technologies that has characterized the end of the 20th and the beginning of the 21st centuries has profoundly impacted the way water management issues are studied. The possibility of collecting and storing large data sets has allowed the development of new classes of models that try to infer the relationships between the variables of interest directly from data rather than fit the classical physical and chemical laws to them. This approach, known as “data-driven,” belongs to the broader area of machine learning (ML) methods and can be applied to many water management problems.
In hydrological modeling, ML tools can process diverse data sets, including satellite imagery, meteorological data, and historical records, to enhance predictions of streamflow, groundwater levels, and water availability and thus support water allocation, infrastructure planning, and operational decision-making.
In water demand management, ML models can analyze historical water consumption patterns, weather data, and socioeconomic factors to predict future water demands. These models can support water utilities and policymakers in optimizing water allocation, planning infrastructure, and implementing effective conservation strategies.
In reservoir management, advanced ML tools may be used to determine the operating rule of water structures by directly searching for the management policy or by mimicking a set of decisions with some desired properties. They may also be used to develop surrogate models that can be rapidly executed to determine the optimal course of action as a component of a decision-support system.
ML methods have revolutionized water management studies by showing the power of data-driven insights. Thanks to their ability to make accurate forecasts, enhanced monitoring, and optimized resource allocation, adopting these tools is predicted to expand and consistently modify water management practices. Continued advancements in ML tools, data availability, and interdisciplinary collaborations will further propel the use of ML methods to address global water challenges and pave the way for a more resilient and sustainable water future.
Article
Managed Aquifer Recharge as a Tool to Improve Water Security and Resilience
Mary-Belle Cruz-Ayala and Sharon B. Megdal
Groundwater overdraft is an issue faced by urban and rural water users worldwide. With climate change making efforts to meet global water demands even more challenging, improving water security and resilience is of paramount importance. Managed aquifer recharge efforts are being deployed globally to further achieve water management goals, such as helping to reduce groundwater overdraft at a local level. Artificial recharge or managed aquifer recharge (MAR) is a concept that has been applied to describe diverse methods with the aim of both augmenting groundwater resources during times when water is available and recovering the water from the same aquifer in the future when it is needed.
MAR projects are distributed in almost every continent. An extensive study published in 2018 identified that 15 countries and regions account for 76% of the installed MAR capacity (Australia, China, France, Finland, India, Israel, Italy, Jordan, Netherlands, Qatar, Southern Africa, Spain, United States, and United Kingdom). MAR is considered a viable tool to face the negative impacts of climate change and to increase public water supply at a local level. In arid and semiarid regions, MAR plays an important role because it allows the storage of large volumes of water without the risk of evaporation. MAR is used to provide water for agricultural activities in groundwater-dependent countries and regions. Increasingly, at least in India, many MAR projects are designed to protect domestic water supply. MAR is also used as a water source for maintaining environmental services, although this use is still incipient.
Article
Moving to General Equilibrium: The Role of CGEs for Economic Analysis of Water Infrastructure Projects
Kenneth M. Strzepek and James E. Neumann
The desire of policymakers and public finance institutions to understand the contribution of water infrastructure to the wider economy, rather than the value of project-level outputs in isolation, has spawned a multidisciplinary branch of water resource planning that integrates traditional biophysical modeling of water resource systems with economy-wide models, including computable general equilibrium models. Economy-wide models include several distinct approaches, including input–output models, macro-econometric models, hybrid input–output macro-econometric models, and general equilibrium models—the term “economy-wide” usually refers to a national level analysis, but could also apply to a sub-national region, multi-nation regions, or the world. A key common characteristic of these models is that they disaggregate the overall economy of a country or region into a number of smaller units, or optimizing agents, who in turn interact with other agents in the economy in determining the use of inputs for production, and the outcomes of markets for goods. These economic agents include industries, service providers, households, governments, and many more. Such a holistic general equilibrium modeling approach is particularly useful for understanding and measuring social costs, a key aim in most cost–benefit analyses (CBAs) of water infrastructure investments when the project or program will have non-marginal impacts and current market prices will be impacted and an appropriately detailed social accounting matrix is available. This article draws on examples from recent work on low- and middle-income countries (LMICs) and provides an outline of available resources that are necessary to conduct an economy-wide modeling analysis. LMICs are the focus of larger water resource investment potential in the 21st century, including large-scale hydropower, irrigation, and drinking water supply. A step-by-step approach is illustrated and supports the conclusion that conditions exist to apply these models much more broadly in LMICs to enhance CBAs.
