Rebecca Tharme | Griffith University (original) (raw)
Papers by Rebecca Tharme
Environmental Reviews
Environmental flows (e-flows) aim to mitigate the threat of altered hydrological regimes in river... more Environmental flows (e-flows) aim to mitigate the threat of altered hydrological regimes in river systems and connected waterbodies and are an important component of integrated strategies to address multiple threats to freshwater biodiversity. Expanding and accelerating implementation of e-flows can support river conservation and help to restore the biodiversity and resilience of hydrologically altered and water-stressed rivers and connected freshwater ecosystems. While there have been significant developments in e-flows science, assessment and societal acceptance, implementation of e-flows within water resources management has been slower than required and geographically uneven. This review explores critical factors that enable successful e-flows implementation and biodiversity outcomes in particular, drawing on 13 case studies and the literature. It presents e-flows implementation as an adaptive management cycle enabled by 10 factors: legislation and governance, financial and huma...
Ecohydrology, 2021
Classifying rivers into homogeneous categories based on hydrological and/or environmental attribu... more Classifying rivers into homogeneous categories based on hydrological and/or environmental attributes supports the implementation of environmental flows to sustain aquatic ecosystems and support the resource needs of society. Hydrological classifications provide decision‐makers with a pragmatic number of water management units by grouping individual rivers or river segments expected to exhibit similar biophysical responses to flow alteration. Such classifications are particularly useful across broad geographies and in data‐limited contexts, such as in Tanzania, where the legal requirement to implement environmental flows for all major waterbodies remains constrained by scant data. We present a two‐level hydrological classification of all Tanzanian basins and the Rufiji River Basin. For the Rufiji River Basin, the largest river basin in the country, we performed an inductive classification based on the availability of long‐term time series of daily average discharge. We clustered 28 g...
BioScience, 2020
Despite their limited spatial extent, freshwater ecosystems host remarkable biodiversity, includi... more Despite their limited spatial extent, freshwater ecosystems host remarkable biodiversity, including one-third of all vertebrate species. This biodiversity is declining dramatically: Globally, wetlands are vanishing three times faster than forests, and freshwater vertebrate populations have fallen more than twice as steeply as terrestrial or marine populations. Threats to freshwater biodiversity are well documented but coordinated action to reverse the decline is lacking. We present an Emergency Recovery Plan to bend the curve of freshwater biodiversity loss. Priority actions include accelerating implementation of environmental flows; improving water quality; protecting and restoring critical habitats; managing the exploitation of freshwater ecosystem resources, especially species and riverine aggregates; preventing and controlling nonnative species invasions; and safeguarding and restoring river connectivity. We recommend adjustments to targets and indicators for the Convention on B...
Frontiers in Environmental Science, 2018
respect for their rights, responsibilities and systems of governance in environmental water decis... more respect for their rights, responsibilities and systems of governance in environmental water decisions. These social and cultural dimensions of e-flow management warrant far more attention. Actionable recommendations present a pathway forward for a new era of scientific research and innovation, shared visions, collaborative implementation programs, and adaptive governance of environmental flows, suited to new social, and environmental contexts driven by planetary pressures, such as human population growth and climate change.
Aquatic Procedia, 2014
ABSTRACT Environmental flows continue to shift conceptually from a utilitarian means of protectin... more ABSTRACT Environmental flows continue to shift conceptually from a utilitarian means of protecting ‘environmental’ needs – often equated with specific fish species of economic and/or conservation value – within the water resources planning and management cycle to a process underpinning the adaptive, sustainable management of social-ecological aquatic systems for multiple benefits and at multiple scales. We explore some of the ways in which environmental flows are clearly transitioning from a discipline designed mainly to conserve aquatic species, through improved site-level water resources infrastructure operations, to a more sophisticated vehicle for achieving the ever challenging goals for sustainable water management and human well-being. These goals are achieved through good governance and policy, and by setting targets for socioeconomic development and climate-resilient resource management. As these dimensions of the policy and practice evolve, the need grows to engage with and draw upon the expertise of a broader community of stakeholders, from the public and private sectors, the social sciences and civil society.
Fisheries are some of the most valuable natural resources that depend upon natural regimes of riv... more Fisheries are some of the most valuable natural resources that depend upon natural regimes of river flow for their productivity and full development benefits. Managing rivers to sustain these benefits requires that environmental flow requirements of river fisheries be understood and conveyed effectively into decision-making processes at multiple levels within the river basin. The present research report reviews existing environmental flow methodologies and fisheries production models to determine which combination of existing approaches will provide most potential for development of such decision support tools. This is the first comprehensive review of the use of environmental flow methodologies for managing large rivers and floodplains for fisheries production. Previous reviews have focused exclusively on the fisheries models themselves and have not explored how these models can be combined with other approaches to understand and predict the impact of changes in river flow regimes ...
Frontiers in Environmental Science, Nov 11, 2022
CABI eBooks, 2013
At the global scale, humanity is increasingly facing rapid changes, and sometimes shocks, that ar... more At the global scale, humanity is increasingly facing rapid changes, and sometimes shocks, that are affecting the security of our food systems and the agroecosystems that are the ultimate sources of food. To plan and prepare for resilient food production and food security in a sustainable and effi cient way, we are challenged to better understand the conditions and likely responses of these diverse agroecosystems under various drivers of change and scenarios of future trends. Among the many direct drivers and indirect pressures that exist or are emerging, the discussion in this chapter focuses on the main themes of drivers of demographic changes, globalization of economic and governance systems (including markets), and climate change. The current state of health of water and land resources, and of ecosystems and their services, are considered alongside these drivers, as these are critical determinants of the pathways with suffi cient potential to move food-producing systems towards more sustainable production. Hence, addressing the opportunities, synergies and constraints of multiple drivers will be critical for policy advice to build resilient food systems in the future.
Encyclopedia of Inland Waters
Freshwater Ecology and Conservation
Since the emergence of freshwater ecology and conservation as a discipline in the twentieth centu... more Since the emergence of freshwater ecology and conservation as a discipline in the twentieth century, the advances in science, policy, and practice have been considerable, particularly in the areas of applied ecology and the social sciences. Freshwater systems continue to face considerable challenges to their sustainability in the Anthropocene. Most of these challenges, however, are driven by their broader and dynamically changing social-ecological context. Approaches are needed that recognise that people are at the centre of successful freshwater conservation and management, and which are strategically targeted, policy relevant, innovative, and inclusive of social, political, and economic considerations. As this chapter describes, a rich and continually evolving suite of approaches to freshwater conservation already exists worldwide on which to draw, as does the knowledge and experience to support their effective application.
Developing and managing water for agriculture has been and will remain instrumental in providing ... more Developing and managing water for agriculture has been and will remain instrumental in providing food and livelihood security. However, this has come at a high environmental price. The costs range from progressive degradation, fragmentation and drying up of aquatic and
Water for the Environment, 2017
Abstract Environmental water can be implemented using a range of different allocation mechanisms ... more Abstract Environmental water can be implemented using a range of different allocation mechanisms that are legal or policy tools that enable the provision of water for environmental purposes. This chapter identifies five allocation mechanisms and classifies these based on their legal characteristics, function, and operation. There are three allocation mechanisms that provide environmental water by imposing conditions on other water users: caps on consumptive water use, conditions on private water users, and conditions on storage or water resource operators. There are two allocation mechanisms that create specific legal rights for the environment itself: ecological/environmental reserves, and environmental water rights. These allocation mechanisms can be used singly or in combination within the same river system. The main factors that influence the selection of an allocation mechanism(s) in a particular system, and outline the main implementation options and constraints, operational requirements, security, and adaptability of each mechanism are discussed. Case studies from Australia, the United States, South Africa, and China are used to illustrate and explore the implementation of these allocation mechanisms, including several of the factors driving or constraining success.
River Research and Applications, 2015
Watersheds are spatially explicit landscape units that contain a range of interacting physical, e... more Watersheds are spatially explicit landscape units that contain a range of interacting physical, ecological and social attributes. They are socialecological systems that provide a range of ecosystem services valued by the society. Their ability to provide these services depends, in part, on the degree to which they are impaired by human-related activity. An array of indicators is used by natural resource managers, both private and government, to assess watersheds and their sub-components. Often these assessments are performed in comparison with a reference condition. However, assessments can be hampered because natural settings of many systems differ from those sites used to characterize reference conditions. Additionally, given the ubiquity of human-related alterations across landscapes (e.g. atmospheric deposition of anthropogenically derived nitrogen), truly unaltered conditions for most, if not all, watersheds cannot be described. Definitions of 'integrity' have been developed for river ecosystems, but mainly at the reach or site scale and usually for particular species, such as fish or macroinvertebrates. These scales are inappropriate for defining integrity at the watershed scale. In addition, current assessments of endpoints do not indicate the source of impairment. Our definition of watershed 'integrity' is the capacity of a watershed to support and maintain the full range of ecological processes and functions essential to the sustainability of biodiversity and of the watershed resources and services provided to society. To operationalize this definition as an assessment tool, we identify key functions of unimpaired watersheds. This approach can then be used to model and map watershed integrity by incorporating risk factors (human-related alterations or stressors) that have been explicitly shown to interfere with and degrade key functions in watersheds. An advantage of this approach is that the index can be readily deconstructed to identify factors influencing index scores, thereby directly supporting the strategic adaptive management of individual components that contribute to watershed integrity. Moreover, the approach can be iteratively applied and improved as new data and information become available.
Managing water and agroecosystems for food security, 2013
The integrated, efficient, equitable and sustainable management of water resources is of vital im... more The integrated, efficient, equitable and sustainable management of water resources is of vital importance for securing ecosystem health and services to people, not least of which is food production. The challenges related to increasing water scarcity and ecosystem degradation, and the added complexities of climate change, highlight the need for countries to carefully manage their surface water and groundwater resources. Built upon the principles of economic efficiency, equity and environmental sustainability, integrated water resources management (IWRM) can be shaped by local needs to maximize allocative efficiency and better manage water for people, food, nature and industry. However, the flexibility of the approach means that it is interpreted and applied in ways that prioritize and address immediate challenges created by demographic, economic and social drivers, often at the expense of environmental sustainability - and hence also of long-term food security. The need to more expl...
Managing water and agroecosystems for food security, 2013
The integrated role of water in ecosystems and, in particular, in agroecosystems, as well as the ... more The integrated role of water in ecosystems and, in particular, in agroecosystems, as well as the multiple uses of water-across various sectors that have increasing demands, have been widely recognized. But regions and institutions are still struggling to resolve issues around water-be it scarcity, accessibility or degradation. Mostly, they are caught in conventional institutional and policy frameworks that have been set up based more on sectoral than on cross-sectoral principles, thus preventing them from achieving the ultimate goal of sustainability. This chapter analyses the current and future challenges related to water availability and water use for agriculture from this perspective. It looks at water quantity and quality, water infrastructure, and related governance and institutional aspects, using case studies from basins in different geographic regions.
Managing water and agroecosystems for food security, 2013
As growth in population, gross domestic product (GDP) and consumption continues, further demands ... more As growth in population, gross domestic product (GDP) and consumption continues, further demands are placed on land, water and other resources. The resulting degradation can threaten the food security of poor people in fragile environments, particularly those whose livelihoods rely largely on agricultural activities. The concept of diversifi ed or multifunctional agroecosystems is a relatively recent response to the decline in the quality of the natural resource base. Today, the question of agricultural production has evolved from a purely technical issue to a more complex one characterized by social, cultural, political and economic dimensions. Multifunctional agroecosystems carry out a variety of ecosystem services, such as the regulation of soil and water quality, carbon sequestration, support for biodiversity and sociocultural services, as well as meeting consumers' needs for food. In turn, these systems also rely on ecosystem services provided by adjacent natural ecosystems, including pollination, biological pest control, maintenance of soil structure and fertility, nutrient cycling and hydrological services. However, poor management practices in agroecosystems can also be the source of numerous disservices, including loss of wildlife habitat, nutrient runoff, sedimentation of waterways, greenhouse gas emissions, and pesticide poisoning of humans and non-target species. This chapter discusses the challenges to agroecosystem management, and how adopting a diversifi ed approach will enable farmers to farm longer and more sustainably in an environment of greater uncertainty, in the face of climate change.
SYMPOSIUM ON THE …, 2004
Worldwide there is growing awareness of the pivotal role of the flow regime (hydrology) as a key ... more Worldwide there is growing awareness of the pivotal role of the flow regime (hydrology) as a key 'driver'of the ecology of rivers and their associated floodplain wetlands. Ecological processes related to flow and other factors govern the ecosystem goods and ...
Environmental Reviews
Environmental flows (e-flows) aim to mitigate the threat of altered hydrological regimes in river... more Environmental flows (e-flows) aim to mitigate the threat of altered hydrological regimes in river systems and connected waterbodies and are an important component of integrated strategies to address multiple threats to freshwater biodiversity. Expanding and accelerating implementation of e-flows can support river conservation and help to restore the biodiversity and resilience of hydrologically altered and water-stressed rivers and connected freshwater ecosystems. While there have been significant developments in e-flows science, assessment and societal acceptance, implementation of e-flows within water resources management has been slower than required and geographically uneven. This review explores critical factors that enable successful e-flows implementation and biodiversity outcomes in particular, drawing on 13 case studies and the literature. It presents e-flows implementation as an adaptive management cycle enabled by 10 factors: legislation and governance, financial and huma...
Ecohydrology, 2021
Classifying rivers into homogeneous categories based on hydrological and/or environmental attribu... more Classifying rivers into homogeneous categories based on hydrological and/or environmental attributes supports the implementation of environmental flows to sustain aquatic ecosystems and support the resource needs of society. Hydrological classifications provide decision‐makers with a pragmatic number of water management units by grouping individual rivers or river segments expected to exhibit similar biophysical responses to flow alteration. Such classifications are particularly useful across broad geographies and in data‐limited contexts, such as in Tanzania, where the legal requirement to implement environmental flows for all major waterbodies remains constrained by scant data. We present a two‐level hydrological classification of all Tanzanian basins and the Rufiji River Basin. For the Rufiji River Basin, the largest river basin in the country, we performed an inductive classification based on the availability of long‐term time series of daily average discharge. We clustered 28 g...
BioScience, 2020
Despite their limited spatial extent, freshwater ecosystems host remarkable biodiversity, includi... more Despite their limited spatial extent, freshwater ecosystems host remarkable biodiversity, including one-third of all vertebrate species. This biodiversity is declining dramatically: Globally, wetlands are vanishing three times faster than forests, and freshwater vertebrate populations have fallen more than twice as steeply as terrestrial or marine populations. Threats to freshwater biodiversity are well documented but coordinated action to reverse the decline is lacking. We present an Emergency Recovery Plan to bend the curve of freshwater biodiversity loss. Priority actions include accelerating implementation of environmental flows; improving water quality; protecting and restoring critical habitats; managing the exploitation of freshwater ecosystem resources, especially species and riverine aggregates; preventing and controlling nonnative species invasions; and safeguarding and restoring river connectivity. We recommend adjustments to targets and indicators for the Convention on B...
Frontiers in Environmental Science, 2018
respect for their rights, responsibilities and systems of governance in environmental water decis... more respect for their rights, responsibilities and systems of governance in environmental water decisions. These social and cultural dimensions of e-flow management warrant far more attention. Actionable recommendations present a pathway forward for a new era of scientific research and innovation, shared visions, collaborative implementation programs, and adaptive governance of environmental flows, suited to new social, and environmental contexts driven by planetary pressures, such as human population growth and climate change.
Aquatic Procedia, 2014
ABSTRACT Environmental flows continue to shift conceptually from a utilitarian means of protectin... more ABSTRACT Environmental flows continue to shift conceptually from a utilitarian means of protecting ‘environmental’ needs – often equated with specific fish species of economic and/or conservation value – within the water resources planning and management cycle to a process underpinning the adaptive, sustainable management of social-ecological aquatic systems for multiple benefits and at multiple scales. We explore some of the ways in which environmental flows are clearly transitioning from a discipline designed mainly to conserve aquatic species, through improved site-level water resources infrastructure operations, to a more sophisticated vehicle for achieving the ever challenging goals for sustainable water management and human well-being. These goals are achieved through good governance and policy, and by setting targets for socioeconomic development and climate-resilient resource management. As these dimensions of the policy and practice evolve, the need grows to engage with and draw upon the expertise of a broader community of stakeholders, from the public and private sectors, the social sciences and civil society.
Fisheries are some of the most valuable natural resources that depend upon natural regimes of riv... more Fisheries are some of the most valuable natural resources that depend upon natural regimes of river flow for their productivity and full development benefits. Managing rivers to sustain these benefits requires that environmental flow requirements of river fisheries be understood and conveyed effectively into decision-making processes at multiple levels within the river basin. The present research report reviews existing environmental flow methodologies and fisheries production models to determine which combination of existing approaches will provide most potential for development of such decision support tools. This is the first comprehensive review of the use of environmental flow methodologies for managing large rivers and floodplains for fisheries production. Previous reviews have focused exclusively on the fisheries models themselves and have not explored how these models can be combined with other approaches to understand and predict the impact of changes in river flow regimes ...
Frontiers in Environmental Science, Nov 11, 2022
CABI eBooks, 2013
At the global scale, humanity is increasingly facing rapid changes, and sometimes shocks, that ar... more At the global scale, humanity is increasingly facing rapid changes, and sometimes shocks, that are affecting the security of our food systems and the agroecosystems that are the ultimate sources of food. To plan and prepare for resilient food production and food security in a sustainable and effi cient way, we are challenged to better understand the conditions and likely responses of these diverse agroecosystems under various drivers of change and scenarios of future trends. Among the many direct drivers and indirect pressures that exist or are emerging, the discussion in this chapter focuses on the main themes of drivers of demographic changes, globalization of economic and governance systems (including markets), and climate change. The current state of health of water and land resources, and of ecosystems and their services, are considered alongside these drivers, as these are critical determinants of the pathways with suffi cient potential to move food-producing systems towards more sustainable production. Hence, addressing the opportunities, synergies and constraints of multiple drivers will be critical for policy advice to build resilient food systems in the future.
Encyclopedia of Inland Waters
Freshwater Ecology and Conservation
Since the emergence of freshwater ecology and conservation as a discipline in the twentieth centu... more Since the emergence of freshwater ecology and conservation as a discipline in the twentieth century, the advances in science, policy, and practice have been considerable, particularly in the areas of applied ecology and the social sciences. Freshwater systems continue to face considerable challenges to their sustainability in the Anthropocene. Most of these challenges, however, are driven by their broader and dynamically changing social-ecological context. Approaches are needed that recognise that people are at the centre of successful freshwater conservation and management, and which are strategically targeted, policy relevant, innovative, and inclusive of social, political, and economic considerations. As this chapter describes, a rich and continually evolving suite of approaches to freshwater conservation already exists worldwide on which to draw, as does the knowledge and experience to support their effective application.
Developing and managing water for agriculture has been and will remain instrumental in providing ... more Developing and managing water for agriculture has been and will remain instrumental in providing food and livelihood security. However, this has come at a high environmental price. The costs range from progressive degradation, fragmentation and drying up of aquatic and
Water for the Environment, 2017
Abstract Environmental water can be implemented using a range of different allocation mechanisms ... more Abstract Environmental water can be implemented using a range of different allocation mechanisms that are legal or policy tools that enable the provision of water for environmental purposes. This chapter identifies five allocation mechanisms and classifies these based on their legal characteristics, function, and operation. There are three allocation mechanisms that provide environmental water by imposing conditions on other water users: caps on consumptive water use, conditions on private water users, and conditions on storage or water resource operators. There are two allocation mechanisms that create specific legal rights for the environment itself: ecological/environmental reserves, and environmental water rights. These allocation mechanisms can be used singly or in combination within the same river system. The main factors that influence the selection of an allocation mechanism(s) in a particular system, and outline the main implementation options and constraints, operational requirements, security, and adaptability of each mechanism are discussed. Case studies from Australia, the United States, South Africa, and China are used to illustrate and explore the implementation of these allocation mechanisms, including several of the factors driving or constraining success.
River Research and Applications, 2015
Watersheds are spatially explicit landscape units that contain a range of interacting physical, e... more Watersheds are spatially explicit landscape units that contain a range of interacting physical, ecological and social attributes. They are socialecological systems that provide a range of ecosystem services valued by the society. Their ability to provide these services depends, in part, on the degree to which they are impaired by human-related activity. An array of indicators is used by natural resource managers, both private and government, to assess watersheds and their sub-components. Often these assessments are performed in comparison with a reference condition. However, assessments can be hampered because natural settings of many systems differ from those sites used to characterize reference conditions. Additionally, given the ubiquity of human-related alterations across landscapes (e.g. atmospheric deposition of anthropogenically derived nitrogen), truly unaltered conditions for most, if not all, watersheds cannot be described. Definitions of 'integrity' have been developed for river ecosystems, but mainly at the reach or site scale and usually for particular species, such as fish or macroinvertebrates. These scales are inappropriate for defining integrity at the watershed scale. In addition, current assessments of endpoints do not indicate the source of impairment. Our definition of watershed 'integrity' is the capacity of a watershed to support and maintain the full range of ecological processes and functions essential to the sustainability of biodiversity and of the watershed resources and services provided to society. To operationalize this definition as an assessment tool, we identify key functions of unimpaired watersheds. This approach can then be used to model and map watershed integrity by incorporating risk factors (human-related alterations or stressors) that have been explicitly shown to interfere with and degrade key functions in watersheds. An advantage of this approach is that the index can be readily deconstructed to identify factors influencing index scores, thereby directly supporting the strategic adaptive management of individual components that contribute to watershed integrity. Moreover, the approach can be iteratively applied and improved as new data and information become available.
Managing water and agroecosystems for food security, 2013
The integrated, efficient, equitable and sustainable management of water resources is of vital im... more The integrated, efficient, equitable and sustainable management of water resources is of vital importance for securing ecosystem health and services to people, not least of which is food production. The challenges related to increasing water scarcity and ecosystem degradation, and the added complexities of climate change, highlight the need for countries to carefully manage their surface water and groundwater resources. Built upon the principles of economic efficiency, equity and environmental sustainability, integrated water resources management (IWRM) can be shaped by local needs to maximize allocative efficiency and better manage water for people, food, nature and industry. However, the flexibility of the approach means that it is interpreted and applied in ways that prioritize and address immediate challenges created by demographic, economic and social drivers, often at the expense of environmental sustainability - and hence also of long-term food security. The need to more expl...
Managing water and agroecosystems for food security, 2013
The integrated role of water in ecosystems and, in particular, in agroecosystems, as well as the ... more The integrated role of water in ecosystems and, in particular, in agroecosystems, as well as the multiple uses of water-across various sectors that have increasing demands, have been widely recognized. But regions and institutions are still struggling to resolve issues around water-be it scarcity, accessibility or degradation. Mostly, they are caught in conventional institutional and policy frameworks that have been set up based more on sectoral than on cross-sectoral principles, thus preventing them from achieving the ultimate goal of sustainability. This chapter analyses the current and future challenges related to water availability and water use for agriculture from this perspective. It looks at water quantity and quality, water infrastructure, and related governance and institutional aspects, using case studies from basins in different geographic regions.
Managing water and agroecosystems for food security, 2013
As growth in population, gross domestic product (GDP) and consumption continues, further demands ... more As growth in population, gross domestic product (GDP) and consumption continues, further demands are placed on land, water and other resources. The resulting degradation can threaten the food security of poor people in fragile environments, particularly those whose livelihoods rely largely on agricultural activities. The concept of diversifi ed or multifunctional agroecosystems is a relatively recent response to the decline in the quality of the natural resource base. Today, the question of agricultural production has evolved from a purely technical issue to a more complex one characterized by social, cultural, political and economic dimensions. Multifunctional agroecosystems carry out a variety of ecosystem services, such as the regulation of soil and water quality, carbon sequestration, support for biodiversity and sociocultural services, as well as meeting consumers' needs for food. In turn, these systems also rely on ecosystem services provided by adjacent natural ecosystems, including pollination, biological pest control, maintenance of soil structure and fertility, nutrient cycling and hydrological services. However, poor management practices in agroecosystems can also be the source of numerous disservices, including loss of wildlife habitat, nutrient runoff, sedimentation of waterways, greenhouse gas emissions, and pesticide poisoning of humans and non-target species. This chapter discusses the challenges to agroecosystem management, and how adopting a diversifi ed approach will enable farmers to farm longer and more sustainably in an environment of greater uncertainty, in the face of climate change.
SYMPOSIUM ON THE …, 2004
Worldwide there is growing awareness of the pivotal role of the flow regime (hydrology) as a key ... more Worldwide there is growing awareness of the pivotal role of the flow regime (hydrology) as a key 'driver'of the ecology of rivers and their associated floodplain wetlands. Ecological processes related to flow and other factors govern the ecosystem goods and ...