For this disscussion we have three papers to read. [Note by Madhu: Click on the paper titles below to read abstracts, and access the full reprint via Blackboard]
Palmer et al. 1997. Ecological Theory and Community Restoration Ecology.
Suding et al. 2004. Alternative states and positive feedbacks in restoration ecology. [this link is to the reprint PDF via the Suding lab web page]
Provided below is a brief background on Ecological Restoration and a few questions to think about.
Natural Habitats / Ecosystems are degraded, modified, and altered by human activities such as development. Ecological restoration offers a way to reverse the trend (habitat loss and degradation) and to create new opportunities for Biodiversity. Ecological restoration is the process of assisting the recovery of an ecosystem that has been degraded, damaged or destroyed. Restoration is done for many different reasons: for the recovery of endangered species, to reestablish communities, and to return ecosystem structures, functions and processes to natural conditions. The goal of restoration is to create habitats that possess the structural and functional attributes of the natural habitats that they are intended to replace and to create a self supporting ecosystem that is resilient to perturbation without the need for further assistance.
Types of restoration- Passive and Active restoration
Passive Restoration: requires little human input and allows ecosystems to recover on their own.
Active restoration: requires active human input such as modern farming techniques to jump start ecological processes such as plant dispersal and establishment. Most degraded habitats require active restoration.
Provided below are the Steps taken in Active Restoration to restore a degraded habitat.
1. Research the site’s land use history, and find out why this particular site needs to be restored.
2. Outline the objectives for the restoration project because there needs to be some practical means for measuring the success of a restoration project.
3. Identify a reference (remnant) site such as a natural landscape that has not been altered or affected by human activities that can be used to help guide restoration activities.
4. A detailed site description on both the degraded and reference site is conducted to determine vegetation structure (plant composition, density, cover, and height), faunal community structure (composition and relative abundance) not always done, soil type, topography, hydrology and microclimatic conditions.
5. Create a detailed restoration design and management schedule. Restoration designs are usually based upon project objectives, topography, hydrology, soil type, microclimate, native plant species composition at nearby reference sites, and sometimes habitat considerations for wildlife.
6. Implementation of restoration activities:
A. Ground preparation could include agricultural techniques such as spraying, disking, mowing, watering, burning and grazing to remove exotic plant species and prepare the ground for planting. In the event that the soil is contaminated or degraded other procedures will need to be taken to restore soil integrity. Soils on agricultural lands in the Central Valley of CA are generally very fertile and won’t require manipulations.
B. Jump start ecological processes by planting seedlings and cuttings.
C. Employ agriculture techniques such as watering, mowing, and spraying to increase plant establishment and survival.
7. Monitor the development of a restored landscape. Monitoring is an integral part of restoration and allows for rapid adaptation of management actions and can be used to evaluate and refine restoration practices.
You can follow the following link to the Society for Ecological Restoration (SER) website to learn more about SER Primer on Ecological Restoration and the Guidelines for Developing and Managing Ecological Restoration Projects.
Restoration Ecology is light on theory and assumes succession is applied. Restoration Ecology time scale is generally around 3-20 years and sometimes assumes that a site is restored once restoration activities cease. Restoration Ecologists also assume that a successful restoration project will provide favorable conditions for native biota and will be resilient to natural perturbations.
Most restoration projects, under logistical, economic, and knowledge constraints, focus on restoring habitat by reintroducing a subset of the native flora, hoping the remaining plant and animal species from the native community return on their own.
Research / monitoring efforts therefore emphasize the rapid recovery of
ecosystem processes, and have recently begun to address recovery of functional groups in communities.
Restored systems are an underexploited opportunity (“natural” experiments) for evolutionary ecologists to understand basic processes underlying the assembly and evolution of biological communities.
Greater efforts need to be taken to bridge the gap between understanding processes in the ecological (where current efforts areconcentrated) vs. the evolutionary timeframe (where the true implications for biodiversity will be played out). An evolutionary perspective will provide theoretical insights for community ecology and guide future restoration.
Provided below are a list of questions that we should all think about and dissucss in class on monday.
How will communities assemble in actively and passively restored systems.
What role and or effect will invasive species play and have in community assembly?
Most restoration activities (watering, mowing, invasive weed control) only last a few years years. How will community struture and function change in a restored system in 10, 30, or even 50 years once restoration activities cease?
Will communities be resilient to natural disturbances and pertubations?
What role will animals play in succession?
Will species interactions change such as predation, herbivory, and competition?