species to disperse and migrate into diverse habitats. Connectivity among them needs to include longitudinal (between upstream and downstream reaches), lateral (between river and adjacent side channels and floodplains) and vertical (between surface water and groundwater) dimensions. However, this connectedness makes them vulnerable to environmental change in catchments, riparian zones, upstream channels as well as locally at any site.
In particular, dams and weirs have led to fragmentation of freshwater ecosystems and only 23% of large rivers flow uninterrupted to the sea (Grill et al., 2019). Climate change has altered water availability to and within freshwater ecosystems worldwide (Gudmundsson et al., 2021). Land use changes, such as deforestation, have altered river flows such as in Brazil (Levy et al., 2018) and Malawi (Palamuleni et al., 2011) and pollutants have decreased water quality, such as in China (Yan et al., 2015) and river channel alterations have degraded habitats, such as in Europe (Aarts et al., 2004). We recognise that some alteration of freshwater ecosystems, such as dams, diversions and water withdrawals, is essential to support human life, but these activities can be restricted to a few carefully selected river basins allowing others to be restored and conserved.
Restoration of freshwater ecosystems presents many challenges, not least the need to address numerous issues in the
whole catchment feeding these water-dependent systems. Restoration actions often need to include reinstatement
of terrestrial ecosystems within the catchment upstream, riparian restoration, release of appropriate water flows
from storages, installation of fish passes at barriers, reduction of pumping from groundwater, prevention of pollution
from farming and industries, and at-site replacement of habitats. These restoration activities have implications for
many businesses, government departments and agencies, non-governmental organisations and dispersed local
communities, with potential for diverse, conflicting aspirations. Freshwater ecosystem restoration typically requires
collaborative planning, design, decision-making and action at landscape or catchment scale (Finlayson et al., 2018)
and significant effort to integrate traditional cultural and scientific knowledge (Arthington et al., 2018). The emerging
model is that freshwater ecosystems and their catchments are coupled human and natural systems, wherein setting
restoration objectives and devising management solutions require engagement and collaboration among engineers
and hydrologists, ecologists, social scientists and citizens (Bunn 2016; Arthington, 2021).
Adaptive management
A systematic process for continually improving management policies and practices by learning from the outcomes of previously employed policies and practices. (Millennium Assessment). It uses management as a tool to not only change the system, but also learn about the system.
http://www.millenniumassessment.org/documents/
document.776.aspx.pdf Ecological restoration
A process intended to assist the return of an ecosystem to its historical trajectory and to recover a self-sustaining native ecosystem as close to the original state as possible. Restoration can involve a continuum of interventions that vary in scale, intensity and cost and may require long time frames for full recovery.
Ecosystem collapse
A condition when it is virtually certain that an ecosystem’s defining biotic or abiotic features are lost, and the characteristic native biota are no longer sustained. Collapse is considered an endpoint of ecosystem decline and degradation.
Ecosystem degradation
A persistent reduction in the capacity of an ecosystem to support native species and provide ecosystem services.
http://www.millenniumassessment.org/documents/
document.776.aspx.pdf Ecosystem functionality
How well ecosystem processes work together. Ecosystem functions include all of the biological and physical interactions that occur in an environment, such as the exchange of energy and nutrients in the food chain.
Indigenous knowledge (or local knowledge)
The understandings, skills and philosophies developed by societies with long histories of interaction with their natural surroundings. For many Indigenous Peoples and local communities, indigenous knowledge informs decision-making about fundamental aspects of day-to-day life.
Managed ecosystems
Complex, dynamic systems with spatially varying inputs and outputs that are the result of interrelated physical processes, biological processes, and human decision-making processes.
Examples include agricultural and agroforestry systems, forestry plantations, fish farms and other grazing systems.
GLOSSARY
Multi-sector coalition
An alliance or partnership created when individuals and organisations from different sectors – e.g., nonprofit, government, philanthropic, research and business – use their diverse perspectives and resources to jointly solve a societal problem and achieve a shared goal.
Nature’s contributions to people
The contributions, both positive and negative, of living nature (i.e. diversity of organisms, ecosystems, and their associated ecological and evolutionary processes) to the quality of life for people. These contributions include material and non-material aspects.
https://ipbes.net/glossary/natures-contributions-people Net positive practices
A way of doing business that puts back more into society, the environment and the global economy than it takes out. Becoming net positive requires organisations and companies to plan for long-term outcomes, going beyond risk avoidance, externalising environmental damage and incremental improvements.
https://www.forumforthefuture.org/net-positive Reclamation
Commonly used in the context of mined lands where the objective is to return land and watercourses to an acceptable standard of productive use, ensuring that any landforms and structures are stable, and any watercourses are of acceptable water quality. Reclamation typically involves a number of activities such as removing any hazardous materials, reshaping the land, restoring topsoil, and planting native grasses, trees, or ground cover.
Rehabilitation
The reparation of ecosystem processes, productivity and services rendered with regard to achieving the fullest possible re-establishment of the species composition and community structure of the original ecosystem.
Remediation
The reduction or elimination of contaminants from a place where they are not wanted. Phytoremediation is the process of removing toxic metals or other substances from soils or substrates using plant species that accumulate these substances in their tissues.
Bioremediation involves a suite of techniques using bacteria or other microorganisms to break down toxic contaminants.
Restoration
A process intended to assist the return of an ecosystem to its historical trajectory and to recover a self-sustaining native ecosystem as close to the original state as possible. Restoration can involve a continuum of interventions that vary in scale, intensity and cost and may require long time frames for full recovery.
Restoration supply chain
The entire process of making and selling commercial goods to support restoration activities, including every stage from the supply of materials and the manufacture of the goods through to their distribution and sale.
Restorative actions
Actions to prevent, halt and reverse the degradation of ecosystems. Examples of restorative actions can include reducing emissions from deforestation; halting ecosystem degradation;
conserving, sustainably managing and enhancing forest carbon stocks; reducing vulnerability and increasing adaptation to climate change; restoring the structure, function and composition of ecosystems, landscapes and seascapes; improving sustainability of agriculture and fisheries; and rehabilitating mined and polluted areas (see Table 1 for examples).
Rewilding
The practice of returning areas of land to a wild state, including the reintroduction of animal species that are no longer naturally found there.
Semi-natural ecosystem
An ecosystem that has been altered by human actions, but which retains significant native species and ecological interactions.
Silvicultural interventions
Pre-logging or post-logging treatments in natural forest stands or plantations designed to increase sustainable production of commercial timber or to reduce risks of disease and fire.
Treatments can include enrichment planting, thinning, or applying herbicides.
Socio-ecological system
An interdependent and linked system of people and nature, nested across spatial and temporal scales. The social-ecological system is influenced by many external factors such as population growth, technological change, markets, trade and political change.
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