Human Impacts on Cold Environments and the Concept of Environmental Fragility

Fundamental Concepts of Environmental Fragility

• Definition of Environmental Fragility: Environmental fragility refers to the concept of an environment being vulnerable and at risk because it lacks the ability to be resilient and adapt to changes. Such environments are easily damaged or disturbed and are subsequently difficult to restore once they have been destroyed.
• Biotic and Abiotic Balance: In all natural environments, there is a sensitive balance between living (biotic) and non-living (abiotic) components:
  • Abiotic Factors: These include climate, geology, and soils.
  • Biotic Factors: These include flora (plants) and fauna (animals).
• Distinction Between Robust and Fragile Systems: Some natural environments appear robust, meaning they can easily respond to and cope with major natural events, such as forest fires or volcanic eruptions. In contrast, fragile environments are highly susceptible to human-induced disturbances, easily damaged, and characterized by extremely slow recovery rates, if they recover at all.

Specific Factors Contributing to Fragility in Cold Environments

• Slow Nutrient Cycle: Due to the prevailing cold temperatures and nutrient-deprived environment, the nutrient cycles in cold environments are exceptionally slow.
  • Organic matter and foreign objects (such as litter) take a much longer time to break down and decompose compared to other biomes.
  • This slow cycling directly impacts the speed at which an environment can restore itself after being damaged.
• Lack of Biodiversity: The cold and unforgiving climate means that only a limited number of plant and animal species can thrive. This result is a lack of biodiversity, which has several implications:
  • Food chains are limited and highly interdependent; the removal or damage of a single species can spread throughout the entire food chain, affecting all aspects of the ecosystem.
  • Example of Trophic Impact: A decline in the species of krill in the Antarctic causes penguins to migrate to different areas, which in turn affects local seal populations.
• Cold Climatic Conditions: Growth is governed by short summers, long winters, very cold temperatures, and limited rainfall.
  • These factors severely limit plant growth and productivity.
  • Disruptions to the ecosystem take an exceptionally long time to be corrected. For example, it is estimated that it could take over $50\,\text{years}$ for an area of tundra to return to its former state after interference.
  • Concrete Example: It may take $50\,\text{years}$ for tyre tracks in the permafrost to be completely revegetated.
• Highly Adapted Ecosystems: Species in polar regions have evolved specific adaptations to survive extreme cold. Because they are so specialized, they find it difficult to cope when environment variables change (e.g., rising temperatures). This puts them at high risk of loss of biodiversity and species extinction.

Categories and Scales of Human Impacts

• Historical Context of Exploitation: Despite inhospitable climates and difficult terrain or topography, cold environments have hosted limited human populations throughout the Holocene, starting since the Last Glacial Maximum approximately $20,000\,\text{years}$ ago.
• The Modern Drivers of Impact: As the global population expands and economic development seeks untapped natural resources, human impact is increasing in scale and intensity.
• Major Categories of Impact:
  • Global Warming: Recent and prospective impacts of climate change are causing these landscapes to change rapidly.
  • Pollution: Introduction of contaminants into sensitive ecosystems.
  • Development of Infrastructure: Building roads, pipelines, and settlements in remote areas.
  • Economic Activity:
    • Mineral Reserves: Extraction of precious metals and minerals.
    • Oil and Gas Exploitation: Drilling and transportation of fossil fuels.
    • Fishing and Whaling: Large-scale removal of marine biomass.
  • Tourism: Increasing numbers of visitors to remote glacial and polar landscapes.
  • Introduction of Invasive Species: Also known as alien species, which disrupt the existing delicate biological balance.

Sustainable Management and Future Outlook

• The Problem of Sustainability: Sustainability is defined as meeting present needs without compromising the ability of future generations to meet their own needs. Some experts suggest that the inherent fragility of cold environments makes sustainable use nearly impossible.
• Barriers to Sustainability:
  • Low Productivity: Low energy levels and slow growth make regeneration difficult.
  • Inaccessibility and Remoteness: While this once protected these environments, it also makes management and oversight difficult.
  • Specialization: Highly specialized plants and animals cannot easily adapt to the rapid changes caused by humans.
• Fluctuations in Trophic Levels: Populations in cold environments are liable to wide fluctuations in the amount of energy held at different trophic levels.
  • Example: Variations in the populations of lemmings and arctic hares (both subject to short-term and long-term fluctuations) have direct consequences for the populations of their predators, such as arctic foxes and snowy owls.

Questions & Discussion

• Recap Question 1: What are biotic and abiotic components?
  • Response: Biotic components are the living parts of an ecosystem (fauna and flora). Abiotic components are the non-living parts (climate, geology, soils).
• Recap Question 2: What does environmental fragility mean?
  • Response: It is the vulnerability of an environment that lacks resilience and the ability to adapt to change, making it easy to damage and hard to restore.
• Recap Question 3: How can cold environments be considered fragile?
  • Response: Through slow nutrient cycles, low biodiversity, highly specialized species, and slow plant growth rates that make recovery from disturbance (like tyre tracks) take decades.
• Recap Question 4: How might humans impact cold environments? Positively? Negatively? What types of activities?
  • Response: Impacts are largely negative through activities like resource extraction (oil/gas), tourism, infrastructure development, and the overarching threat of global warming.
• Analytical Task: Explain the development of cold-based glaciers.
• Analytical Task: Explain why cold environments are considered to be fragile environments ($4\,\text{marks}$).
• Case Study Requirement: Students must complete a case study for both a UK and non-UK example, detailing:
  • Specific named features created in those environments.
  • Processes that led to their formation.
  • An assessment of the impact of human activity upon the natural systems and physical landscape.