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Ecological Systems Maintaining and Enhancing Natural Features and Minimizing Adverse Impacts of Infrastructure Projects Course Review. Emily Mitchell Ayers, Ph.D. The Low Impact Development Center, Inc. emayers@lowimpactdevelopment.org. Key Message.
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Ecological SystemsMaintaining and Enhancing Natural Features and Minimizing Adverse Impacts of Infrastructure ProjectsCourse Review
Emily Mitchell Ayers, Ph.D. The Low Impact Development Center, Inc. emayers@lowimpactdevelopment.org
Key Message • Human activities often have adverse environmental impacts • Learning to design infrastructure systems that successfully integrate with the environment requires an understanding of ecology and a knowledgebase of sustainable design techniques 7-3
Course Objectives • To become familiar with the basic principles of ecology • To learn to anticipate the ecological impacts of infrastructure projects over their entire life cycles from planning to decommissioning • To learn techniques to prevent, minimize, and mitigate these impacts • To learn how to design infrastructure systems that contribute to productive, environmentally restorative and socially desirable uses of land and protection of native flora and fauna 7-4
Modules of the Course • Course Overview: Ecosystem services and the importance of ecologically-sensitive design • Introduction to Ecology: Ecological theory • Impacts of Infrastructure: What are the major ecological impacts caused by infrastructure, and how do infrastructure projects cause these impacts? 7-5
Modules of the Course • Protecting Habitat: Assessing habitat, prioritizing and creating conservation areas • Integrating Infrastructure: How to design infrastructure projects that work in harmony with their surroundings • Restoring Ecological Function: An overview of the general theory of ecosystem restoration, with examples of restoration in specific contexts 7-6
Ecosystem Services • Ecosystems provide essential services on which humans depend • Provisioning services • Regulating services • Supporting services • Cultural services • Disturbance of ecosystems can lead to loss or degradation of ecosystem services 7-7
Introduction to Ecology • What are ecosystems? • What principles govern ecosystem behavior? • How do ecosystems respond to change? 7-8
What is an Ecosystem? • Ecosystem: a unit that consists of living and non-living components interacting to form a system • Ecosystems are made up of populations of species organized into communities interacting with their physical environment • Ecosystems are almost always open systems with inputs and outputs 7-9
What Principles Govern Ecosystem Behavior? • Ecosystems develop complex feedback mechanisms to conserve materials and energy. • Organisms self-organize into food webs and nutrient cycling pathways. • Each species inhabits a unique ecological niche, and plays a role in maintaining the system. • Keystone species play essential roles. Loss can disrupt ecological function. 7-10
How Do Ecosystems Respond to Change? • Ecosystems are always changing, either due to pulsing predator/prey relationships, disturbance, or gradual succession from pioneer to climax systems • Ecosystem stability is described in terms of resistance to change and resilience • Stability depends on biodiversity, size, location, and connectivity 7-11
Impacts of Infrastructure • What ecological impacts are associated with infrastructure? • How do ecosystems become degraded? • What are the local, national, and global implications? 7-12
What Ecological Impacts Are Associated With Infrastructure? • Habitat loss • Habitat fragmentation • Pollution • Altered river and estuary hydrology • Climate change • Road kills 7-13
How Do Ecosystems Become Degraded? • Direct habitat loss • Habitat fragmentation • Damage to physical environment • Chemical toxicity • Hunting and harvesting • Introduction of exotic species
Impacts in the United States • Habitat loss and fragmentation • Depletion of fresh water resources • Eutrophication • Hydromodification • Air pollution
Global Impacts • Depletion of fresh water resources • Climate change • Excessive nutrient loading • Loss of biodiversity • Habitat loss
Ecologically-Sensitive Design Process • Know where you are • Avoid sensitive areas • Minimize infrastructure impacts • Mitigate unavoidable losses • Improve ecological function where possible
Protecting Habitat • Site assessment • Identifying critical resources • Conservation design techniques 7-18
Site Assessment • Ecologically-sensitive design begins with a thorough site assessment • Identify important habitat areas • Understand how site fits into larger regional landscape
Identifying Critical Resources • Conserve the most important habitat areas • Viable, intact communities • Vulnerable, rare, or sensitive communities • Endemic communities (locally unique) • Maintain and improve connectivity to promote wildlife movement
Conservation Design • Focus development in areas that are: • Previously disturbed • Fragmented • At the edges rather than the center of intact communities • Maintain and improve connectivity to promote wildlife movement
Integrating Infrastructure • The energy signature • Anticipating infrastructure impacts • Minimizing infrastructure impacts
The Energy Signature • Infrastructure projects interact with the ecosystems in which they are situated • Minimizing infrastructure impacts requires understanding and protecting the energy signature of the ecosystem • Energy signature: the set of forcing functions affecting an ecosystem
Forcing Functions • Sunlight level • Temperature • Precipitation • Hydrologic regime • Fire regime • Inputs • Organic matter • Nitrogen • Phosphorus
Key Considerations for Infrastructure • Maintain pre-development hydrology • Maintain pre-development nutrient inputs • Minimize pollution • Maintain pre-development plant cover • Avoid introduction of exotic invasive species
Restoring Ecological Function • Basic principles of ecological restoration • Focus on function, not appearance • Rely on self-organization as much as possible • Examples of restoration techniques • Streams • Wetlands • Lakes and Ponds • Upland ecosystems 7-26
Basic Principles of Ecological Restoration • Consult with experts • Remove barriers to ecological function • Establish key species to jump-start self-organization • Provide connectivity to existing habitat • Be patient!
Examination • Multiple choice • Covers material from each module • Tests understanding of key concepts • Application of principles