🌲Indigenous Peoples and Environmental Change Unit 5 – Ecosystems & Biomes of Western North America

Key Concepts and Definitions

• Ecosystem consists of a community of organisms interacting with each other and their physical environment
• Biome is a large geographical area characterized by distinctive plant and animal communities adapted to that region's climate and other abiotic factors
• Biodiversity refers to the variety of life forms within an ecosystem, including genetic diversity, species diversity, and ecosystem diversity
  • Genetic diversity is the variation in genes within a species
  • Species diversity is the number of different species within an ecosystem
  • Ecosystem diversity is the variety of ecosystems within a given area
• Abiotic factors are non-living components of an ecosystem (temperature, precipitation, soil type)
• Biotic factors are living components of an ecosystem (plants, animals, microorganisms)
• Ecological niche is the role and position a species has in its environment, including how it meets its needs for food and shelter, how it survives, and how it reproduces
• Carrying capacity is the maximum population size of a species that an environment can sustain indefinitely, given the available resources

Major Ecosystems and Biomes

• Tundra is characterized by low temperatures, short growing seasons, and limited precipitation, supporting hardy plants (lichens, mosses) and animals (caribou, muskox)
• Boreal forest, also known as taiga, is dominated by coniferous trees (spruce, fir) and experiences long, cold winters and short, cool summers
• Temperate rainforest is characterized by high rainfall, cool temperatures, and tall, dense coniferous forests (redwoods, Douglas fir)
  • Supports a wide variety of plant and animal life, including many endemic species
• Temperate deciduous forest experiences distinct seasons, with trees that lose their leaves in the fall (oak, maple) and a diverse array of understory plants and animals
• Grassland is dominated by grasses and herbaceous plants, with few trees, and is maintained by periodic fires and grazing by large herbivores (bison, pronghorn)
• Desert is characterized by low precipitation, extreme temperatures, and sparse vegetation adapted to conserve water (cacti, sagebrush)
• Chaparral is a Mediterranean-climate ecosystem characterized by shrubby vegetation adapted to hot, dry summers and mild, wet winters (manzanita, chamise)
• Wetlands are areas saturated by water, supporting aquatic plants (cattails, rushes) and animals (waterfowl, beavers)

Indigenous Perspectives on Ecosystems

• Many Indigenous cultures view ecosystems as interconnected webs of life, with humans as an integral part of the natural world
• Traditional Ecological Knowledge (TEK) is a cumulative body of knowledge, practices, and beliefs about the relationships between living beings and their environment, handed down through generations
• Indigenous land management practices, such as controlled burning and selective harvesting, have shaped ecosystems for thousands of years
  • Controlled burning promotes the growth of desired plants, reduces the risk of catastrophic wildfires, and enhances habitat for game animals
  • Selective harvesting ensures the sustainable use of resources and maintains ecological balance
• Indigenous stories and oral histories often convey important ecological knowledge and cultural values related to the environment
• Sacred sites and cultural keystone species hold significant spiritual and cultural importance for Indigenous communities and are often tied to the health and well-being of ecosystems
• Indigenous languages contain valuable information about the natural world, including names for plants, animals, and ecological processes
• Indigenous peoples have developed diverse agricultural systems adapted to local ecosystems, such as the Three Sisters (corn, beans, and squash) in Eastern North America and the milpa system in Mesoamerica

Environmental Factors and Adaptations

• Climate, including temperature and precipitation patterns, is a major determinant of the distribution and characteristics of ecosystems and biomes
• Soil type and quality influence the growth and distribution of plants, which in turn affect the animals that depend on them
• Elevation and topography create microclimates and influence the distribution of species and ecosystems
• Disturbances, such as fires, floods, and windstorms, play important roles in shaping ecosystems and maintaining biodiversity
  • Many species have adaptations that allow them to survive or even thrive in the wake of disturbances
• Adaptations are physical or behavioral characteristics that help organisms survive and reproduce in their environment
  • Examples of physical adaptations include the thick fur of mammals in cold climates, the water-storing leaves of succulents in deserts, and the streamlined bodies of aquatic animals
  • Examples of behavioral adaptations include the migration of birds to avoid harsh winters, the hibernation of bears to conserve energy, and the nocturnal activity of many desert animals to avoid heat stress
• Coevolution occurs when two or more species evolve in response to each other, such as the specialized relationships between plants and their pollinators
• Keystone species have a disproportionately large impact on their ecosystem relative to their abundance (sea otters in kelp forests, beavers in wetlands)

Human Impact and Conservation

• Human activities, such as habitat destruction, overexploitation, pollution, and climate change, have significant impacts on ecosystems and biodiversity
• Habitat fragmentation occurs when large, continuous habitats are divided into smaller, isolated patches, which can reduce the viability of populations and disrupt ecological processes
• Invasive species, often introduced by humans, can outcompete native species and alter ecosystem dynamics
• Overexploitation of resources, such as overfishing and unsustainable logging, can lead to the depletion of species and the degradation of ecosystems
• Pollution, including air, water, and soil contamination, can have detrimental effects on the health of ecosystems and the organisms that inhabit them
• Climate change, largely driven by human activities, is causing shifts in the distribution and abundance of species, altering ecosystem processes, and increasing the frequency and intensity of disturbances
• Conservation efforts aim to protect and restore ecosystems and biodiversity through various strategies:
  • Protected areas, such as national parks and wildlife refuges, safeguard important habitats and species
  • Habitat restoration involves actively repairing degraded ecosystems to improve their ecological function and biodiversity
  • Sustainable resource management practices, such as ecosystem-based fisheries management and selective logging, aim to balance human use with ecological integrity
  • Community-based conservation engages local communities in the stewardship of their natural resources, often incorporating traditional ecological knowledge

Traditional Ecological Knowledge

• Traditional Ecological Knowledge (TEK) is a valuable resource for understanding and managing ecosystems, particularly in the face of environmental change
• TEK is often place-based and specific to the local environment, reflecting the intimate relationship between Indigenous peoples and their homelands
• Indigenous land management practices, such as controlled burning and selective harvesting, are informed by TEK and have been used to maintain ecosystem health and productivity for generations
• TEK can provide important insights into the historical range of variability of ecosystems, informing conservation targets and management strategies
• Indigenous knowledge of plant and animal species, including their ecological roles, life histories, and cultural significance, can contribute to biodiversity conservation efforts
• TEK often emphasizes the importance of reciprocity and respect in human-environment relationships, promoting sustainable resource use and stewardship
• Incorporating TEK into environmental decision-making can lead to more socially and ecologically resilient outcomes, as well as support the rights and well-being of Indigenous communities
• Challenges to integrating TEK into contemporary conservation and management include differences in worldviews, power imbalances, and the need for respectful and equitable collaboration between Indigenous and non-Indigenous partners

Case Studies and Examples

• The Klamath River Basin in California and Oregon is home to several Indigenous tribes (Yurok, Karuk, Hoopa) who have long managed the landscape using practices such as controlled burning and selective fishing
  • Collaborative efforts between tribes, government agencies, and conservation organizations have aimed to restore the river's salmon populations and improve water quality, while respecting tribal sovereignty and traditional ecological knowledge
• The Blackfeet Nation in Montana has been working to restore bison to their traditional lands in Glacier National Park, recognizing the ecological and cultural importance of this keystone species
  • The Iinnii Initiative (iinnii means bison in Blackfeet) aims to establish a free-roaming bison herd on the reservation, contributing to grassland restoration and cultural revitalization
• The Menominee Nation in Wisconsin has practiced sustainable forestry on their reservation for over 150 years, guided by their traditional values of respect for nature and concern for future generations
  • The Menominee Forest is often cited as a model of sustainable forest management, maintaining a high level of biodiversity and productivity while supporting the tribe's economic and cultural well-being
• The Inuit of the Arctic have a deep understanding of sea ice dynamics and the ecology of marine mammals, which has been essential for their subsistence hunting and cultural practices
  • As climate change causes rapid changes in sea ice extent and duration, Inuit traditional ecological knowledge is becoming increasingly important for understanding and adapting to these impacts on Arctic ecosystems and communities

Current Challenges and Future Outlook

• Climate change poses significant challenges to ecosystems and biodiversity, causing shifts in species distributions, altering ecosystem processes, and increasing the frequency and intensity of disturbances
  • Indigenous communities are often disproportionately affected by climate change impacts, due to their close relationships with the land and reliance on natural resources
• Habitat loss and fragmentation continue to be major threats to biodiversity, driven by land-use changes such as urbanization, agriculture, and resource extraction
• Invasive species are a growing problem in many ecosystems, often outcompeting native species and altering ecosystem dynamics
  • Climate change may exacerbate the spread and impact of invasive species, as changing conditions create new opportunities for establishment and spread
• Overexploitation of resources, such as overfishing and unsustainable logging, remains a significant challenge in many regions, despite increasing awareness of the need for sustainable management
• Pollution, including air, water, and soil contamination, continues to have detrimental effects on ecosystems and human health, particularly in areas with limited environmental regulations or enforcement
• Integrating traditional ecological knowledge and Indigenous perspectives into conservation and management is an ongoing challenge, requiring respectful and equitable collaboration between Indigenous and non-Indigenous partners
• Addressing these challenges will require a combination of scientific research, policy action, and community engagement, with a focus on supporting the rights and well-being of Indigenous peoples and their traditional territories
• Ecosystem-based approaches to conservation and management, which consider the complex interactions between species and their environments, offer promising strategies for building resilience in the face of environmental change
• Investing in Indigenous-led conservation initiatives and supporting the revitalization of traditional ecological knowledge can contribute to more socially and ecologically sustainable outcomes for ecosystems and communities in Western North America and beyond