Biodiversity Conservation and Land Use Planning

Posted on Feb 23, 2025 in Other university degrees and diplomas

Why Should We Be Concerned About Biodiversity?

  • Because species extinctions are irreversible.

Landscape Fragmentation: A Major Threat to Biodiversity

  • Fragmentation decreases the amount of natural habitat in a landscape and apportions the remaining habitat into smaller, more isolated pieces.
  • Under the 1973 Endangered Species Act, federal agencies are required to protect all species of plants and animals facing possible extinction.

Preserving Biodiversity: Values and Future Options

Preserving biodiversity keeps future options that support 3 types of values:

  • Direct Utilitarian Values
    • Medical value (prescription drugs and antibiotics)
    • Food sources like fisheries
    • Economic production value like forestry
  • Indirect Utilitarian Values
    • Soil generation for crop production
    • Assimilation of waste and filtration of pollutants
    • Pollination of crops by pollinator species
    • Controlling of floods by wetland
  • Aesthetic Values
    • Human appreciation of nature’s beauty
    • Spiritual or ethical appreciation of biodiversity for its own sake

Limitations of Spatial Information

Spatial information collected is often too general and cannot be tied to fine-grained land use decisions that are influenced by local zoning and subdivision codes.

FEMA Maps and the National Flood Insurance Program (NFIP)

  • FEMA maps, under the National Flood Insurance Program (NFIP), identify the boundaries and probability of flood events.
  • The magnitude (severity) of different zones within the 100-year floodplain are delineated on the flood hazard maps.
  • Zones: channel, floodway, floodway fringe.

Environmental Analysis Techniques for Land Use Planning

The effectiveness of land use planning depends on environmental analysis techniques. There are three broad types of analysis:

  • Composite land suitability analysis
  • Environmental impact analysis
  • Carrying capacity analysis

Phases of Composite Land Suitability Analysis

  • Phase I: Landscape Features: Identify features, e.g., for residential: floodplain, stream buffer, slope, and soil permeability.
  • Phase II: Data Conversion: Apply GIS spatial data functions to prepare data files.
  • Phase III: Define Suitability Analysis Rules:
    • Pass/fail screening technique
    • Weighted rating technique (e.g., 2 for slope, 1 for permeability)
  • Phase IV: Composite Suitability Score: Reclassify to simplify it (<3 low, >6 high, 3-6 medium).
  • Phase V: Products: Transform the outcome into a suitability map.

Methods for Identifying Environmental Impacts

Three common simple ways for identifying impacts:

  • Checklists: To help public agency staff review Environmental Impact (EI).
  • Impact matrices: A list of characteristics of a proposed development and their interaction with its surroundings.
  • Flowcharts: To identify direct and indirect impacts of a proposed land use.

Other Types of EIA Methods

  • Visual assessment:
    • Judging the visual impacts of alternative plans.
    • Effective in major differences.
  • Numerical indicators: Tabulation of outcomes.
  • Single-function models: Display the interactions among factors related to a particular activity or function (e.g., Fate and Transport of Groundwater models).
  • Linked models: Integrate multiple single-function models into a coordinated system (output of one model becomes input to the other model).

Factors in Carrying Capacity Analysis

  • Change factor: A measure of proposed land use change.
  • Limiting factor: Natural resources or infrastructure facilities that are limited in supply.

Types of Limiting Factors

  • Environmental: Water quality, stability of habitats, soil erosion.
  • Physical infrastructure: Water supply, roads.
  • Psychological: How people perceive environmental quality and adequate level of service from infrastructure.
    • This analysis requires a maximum or minimum value determined for a limiting factor.

Integrated Environmental Analysis

Integrating carrying capacity, impact, and land sustainability analysis gives better results in environmental analysis for land use planning. This integration helps decision-makers to understand the emerging environmental conditions, problems, and their causes.