Keywords and Concepts

Ecological Restoration

The process of assisting the recovery of an ecosystem that has been degraded, damaged, or destroyed.

Restoration Ecology

The branch of science that provides concepts, models, methodologies, and tools for the practice of ecological restoration.

Also benefits from direct observation of and participation in restoration practices.

Biodiversity

The variability among living organisms from all sources, including terrestrial, marine, and other aquatic ecosystems and the ecological complexes of which they are part.

Includes the diversity within species, between species, and of ecosystems.

Ecosystem Services

The direct and indirect contributions of ecosystems to human well-being.

They include the production and maintenance of clean soil, water, and air; the moderation of climate and disease; nutrient cycling and pollination; the provisioning of a range of goods useful to humans (food, medicine, fuel); and potential for the satisfaction of aesthetic, recreation, and other human values.

Reclamation

Making severely degraded land fit for cultivation or a state suitable for some human use.

No native reference model defined or used; emphasis is given to returning the site to an anthropocentrically useful condition.

Remediation

A management activity that aims to remove sources of degradation, such as the removal or detoxification of contaminants or excess nutrients from soil and water.

Cleaning up or mitigating environmental pollution to reduce its harmful effects on human health and the ecosystem.

Rehabilitation

Actions that aim to reinstate a level of ecosystem functionality where the goal is not restoration, but rather the provision of ecosystem services.

Returns the land to a form and productivity in conformity with a prior land use plan, including a similar and stable ecological state.

Degradation

A level of deleterious human impact to ecosystems that results in the loss of biodiversity and simplification or disruption in their composition, structure, and functionality and generally leads to a reduction in the flow of ecosystem goods and services.

Reference Model

A native ecosystem that serves as a model for ecological restoration, which is informed by various sources of information, often including one or multiple reference sites.

Usually represents a non-degraded version of the ecosystem that would have existed on the restoration site had degradation not occurred, but adjusted to accommodate predicted environmental conditions.

Natural Regeneration

An approach that relies on spontaneous increases in biota without direct reintroduction after the removal of degrading factors alone.

Assisted Regeneration

An approach that focuses on actively triggering any natural regeneration capacity of biota remaining on site or nearby.

Interventions include removing pest organisms, managing disturbance regimes, and installing resources for colonization.

Active Restoration

An approach in which there is extensive human intervention to influence the rate and trajectory of recovery and the arrival of the biota is largely or entirely dependent on human agency.

Reconstruction

An approach where the arrival of appropriate biota is entirely dependent upon human agency, as they cannot regenerate or recolonize within feasible time frames, even after expert assisted regeneration interventions.

Biocultural Restoration

The science and practice of restoring ecosystems, while also restoring the human and cultural relationships to the place.

Revitalizes the cultural practices, knowledge, and values of the communities that are intrinsically connected to those ecosystems.

Traditional Cultural Ecosystem

Ecosystems that have developed under the joint influence of natural processes and human-imposed organization to provide community composition, ecosystem structure, and ecosystem processes more useful to human exploitation.

Rewilding

Restoring an area of land to its uncultivated or wild state.

Used especially with reference to the reintroduction of species of wild animals that have been driven out or exterminated so as to restore the processes that they affected (e.g., seed dispersal, grazing).

Forest and Landscape Restoration

A planned process that aims to regain ecological functionality and enhance human well-being in deforested or degraded landscapes.

Seeks to restore ecological processes such as hydrological and nutrient cycles, soil development, and wildlife population dynamics at a larger (landscape) scale.

Develops diverse, productive, and multifunctional landscapes that are resilient in the face of economic fluctuations and climate change, instead of maximizing tree cover.

Mitigation

A series of actions taken to minimize the environmental damage of a development or danger to a species of concern.

Potential steps include avoiding project alternatives that would be particularly damaging, modifying the project to minimize negative impacts to the degree possible, compensating for or offsetting impacts that cannot be avoided (compensatory), and reducing greenhouse gas emissions.

Baseline Inventory

A description of current biotic and abiotic elements of a site prior to ecological restoration, including its compositional, structural, and functional attributes.

This is implemented at the commencement of the restoration planning stage, along with the development of a reference.

Novel Ecosystem

A non-historical or new species assemblage due to anthropogenic environmental changes, land conversion, species invasions, extinctions, or a combination of these factors.

Historical Fidelity

The idea that the practice of restoration should attempt to approximate, within reasonable bounds, some past state of the damaged ecosystem.

Demand that an ecosystem not just provide a wildlife habitat, but perform the same kinds of functions that it did so in the past.

Stakeholders

All people and organizations who are involved in or affected by an action or policy and may be directly or indirectly included in the decision-making process.

Typically include government representatives, businesses, nongovernmental organizations, scientists, landowners, and local users of natural resources.

Monitoring

The systematic and orderly gathering of data over a period of time so as to evaluate whether specific project objectives are achieved.

Adaptive Management

An ongoing process for improving management practices by applying knowledge learned through assessment of previously employed practices to improve current and future projects.

The practice of revisiting management decisions and revising them in the light of new information.

Shifting Baselines

The phenomenon whereby each successive generation assumes that the diminished biological state is the norm, rather than recognizing that this state has itself been altered by prior human activities.

Ecological Succession

Patterns of change and replacement occurring within ecosystems over time in response to disturbance or lack of disturbance.

The process by which species composition changes in a biological community over time, which determines the structure and function of the ecosystem.

Community Assembly

The process that dictates how the different species in a shared environment come together, persist, and change over time to form ecological communities.

Disturbance Regime

The pattern, frequency, and timing of disturbance events that are characteristic of an ecosystem over a period of time.

Ecological Resilience

Ability of an ecosystem to recover once a disturbance ends.

Ecological Resistance

Ability of an ecosystem to persist or withstand a disturbance.

Alternative States

Other ecosystem types or environmental conditions that may persist at a particular spatial extent and temporal scale.

Hysteresis

A phenomenon where an ecosystem’s response to environmental changes is not immediately reversible, leading to abrupt and sometimes irreversible transitions between different stable states.

The path of change (degradation) is different from the path of recovery, meaning that past conditions influenced the current state of the ecosystem.

Historical Contingency

Ecosystem states are shaped by past events, not just current events, making history a key factor in ecology.

Facilitation

A species interaction in which one species benefits and the other neither benefits nor is harmed.

Metapopulation

A set of partially isolated populations of a given species.

Long-term survival of the species depends on a shifting balance between local extinctions and recolonizations.

Fragmentation

The process whereby a continuous habitat is transformed into a series of disconnected sites.

The emergence of discontinuities in an environment, which often results in a decrease in biodiversity (especially for species with limited dispersal abilities).

Connectivity

The unimpeded movement of species and the flow of ecological processes across landscapes and ecosystems.

The degree to which different habitats and ecosystems are linked together.

Edge Effects

Changes in resource availability and physical / biological conditions that occur at the boundary of ecosystems or within adjacent ecosystems.

Often leads to increased light penetration, temperature changes, and altered humidity levels, which cause the changes in population or community structures at the boundary.

Buffer Strip

Narrow strips of vegetation adjacent to wetlands or rivers that serve to filter sediments and pollutants from nearby land uses and provide flood protection services and riparian habitat.

Corridor

Uninterrupted wildlife areas designed to link isolated patches of natural habitat across a landscape.

These help to maintain or recover a certain degree of cohesion in otherwise fragmented ecosystems.

Stepping Stones

A series of small, isolated patches of suitable habitats that facilitate the movement of species across fragmented landscapes.

These non-connected habitats allow wildlife to find shelter, food, or rest.

Matrix Permeability

The degree to which the dominant, non-habitat land cover in a region allows or impedes the movement of species between isolated patches of suitable habitat.

The degree to which organisms are capable of moving through a landscape.

Influences an organism’s ability to access resources, find mates, escape unfavorable conditions, and colonize new areas.

Habitat Heterogeneity

Degree of variation in the physical and biological characteristics of a habitat.

Environmental diversity and the ways it shapes ecosystem complexity and species richness.

The presence of varied habitats provides a greater number of ecological niches, thereby supporting a higher species richness and more complex trophic interactions within a given area.

Nurse Plant

A plant that facilitates the establishment of other plants by various mechanisms, such as attracting seed dispersers, increasing nutrient availability, or ameliorating stressful microclimatic conditions.

Applied Nucleation

A strategy that uses the establishment of small patches of vegetation (often trees or shrubs) to serve as focal areas for ecosystem recovery by enhancing colonization.

Uses principles of colonization of non-forested landscapes by wood vegetation to restore forest cover via “tree islands.”

Framework Species Method

An ecological strategy that involves reintroducing the minimum number of species required to reinstate ecosystem structure and processes and to enable recolonization by additional species from adjacent areas.

In forest ecosystems, it often combines the planting of several species that attract fauna and are from different stages of succession.

Afforestation

The process of planting trees on land that has not been previously forested.

Hydrological Regime

The timing and magnitude of water-flow patterns in aquatic systems.

Hydrograph

A graphical representation of stream flow over time, illustrating variation in discharge that are influenced by factors such as precipitation and seasonal changes.

Shows how the height of the water above a reference datum has changed over time.

Base Flow

The portion of the streamflow that is sustained between precipitation events, fed to streams by delayed pathways.

Not runoff, but groundwater flowing into the channel over a long time with a certain delay.

Floodplain

The region of low-lying land adjacent to a river, typically composed of high nutrient sediments and subject to regular flooding in the absence of human intervention.

Flow Regime

The characteristic pattern and variability of water flow in a river or stream over time.

It is characterized by the peak and base flows; the frequency, duration, and timing of flooding; and how fast the flow increases or decreases.

Total Daily Maximum (TDM)

The maximum amount of pollution that a waterbody can assimilate without violating water quality standards.

This includes pollutants that come from point sources (e.g., end of a pipe) and nonpoint sources (e.g., stormwater runoff).

Non-Point Source Pollution

Pollutants that enter the water, air, or soil from diffuse sources, such as the case of excess fertilizer runoff from agricultural fields entering a river.

Beaver Dam Analog

Human-made structures built with natural materials that are inspired by beavers and improve the health of aquatic ecosystems.

Back up small stretches of moving water in stream channels, which creates a habitat for animals, helps connect the water table to wetland vegetation, catches sediment, and increases complexity in the stream channel.

Stage Zero Restoration

A river restoration approach that aims to restore the state of a river to what it was before human disturbance or land use.

It uses intensive methods to reconnect a stream to its floodplain, such as adding meanders, cutting out new channels, filling in deeper channels, and recontouring the banks to reduce stream incision.

Best Management Practices

A practice, or combination of practices, that are effective and practical means of preventing or reducing the amount of pollution generated by nonpoint sources.

SMART Goal / Objective

Specific — clear, concise goal.

Measurable — quantifiable data that has easy-to-track benchmarks.

Achievable — goal can be achieved or successful.

Relevant — goal aligns or contributes meaningfully to overall mission.

Timebound — goal as a deadline to hold the team accountable.

Mycorrhizae

A type of fungi that form a mutualistic association with a plant root.

The fungus extracts carbohydrates from the plant root while increasing the uptake of phosphorus, other mineral nutrients, and water for the plant.

Rhizobia

Soil bacteria that form nodules on the roots of legumes and fix atmospheric nitrogen.

The bacteria receives carbon and energy while supplying the plant with nitrogen.

Cover Crop

A non-cash crop planted between periods of regular crop production or before a restoration planting to prevent soil erosion and improve soil quality, usually by providing humus or nitrogen.

Crops grown to cover soil rather than for harvesting.

Usually grasses (rye), legumes, and forbs.

Waterbar

Human-made structures built along trails or roads to slow and redirect water flow and reduce erosion.

Bioremediation

The use of living organisms to treat toxic wastes or remediate contaminated soil, water, or air.

Phytoremediation

The treatment of pollutants or waste by the use of trees, grasses, or other vegetation.

These living plants remove, degrade, or stabilize the undesirable substances (e.g., toxic metals, pesticides, solvents, explosives, crude oil).

Brownfield

A previously developed land that may be contaminated, especially one considered as a potential site for redevelopment.

Invasive Species

Species that spread rapidly and have the capacity to dominate available habitats to the detriment of native species, ecosystem processes, and ecosystem services.

Primarily nonnative, but this term sometimes refers to aggressive native species for which the population is growing rapidly due to anthropogenic impacts.

Native Species

Taxa that are considered to have their origins in a given region or that have arrived there without recent (direct or indirect) transport by humans.

Weed

A plant that is considered undesirable in a particular place, as they typically overgrow or choke out more desirable plants, especially on cultivated ground (e.g., agriculture).

Their growth often conflicts with human preferences, needs, or goals.