Humans live in or adjacent to wildland ecosystems that burn periodically and are part of nearly all ecosystems that are in the pyrosphere. There are many hazards posed by wildfire and certain consequences of living in these ecosystems. Most are associated with wildfire, but the increased use of prescribed fire is an issue because of associated risks with human attempts to manage ecological goals. The hazards posed by wildfire involve cultural and economic loss, social disruption, infrastructure damage, human injury and mortality, damage to natural resources, and deterioration in air quality. The economic and human health and safety costs are on the rise due to increasing wildland-urban interface problems and extreme wildfire behavior brought on by climate change. In the past, urban fires have been the greatest threat to human health and safety killing over 100,000 people. World ecosystems have been modified extensively by fire. We live on a “fire planet.” With larger human populations and a changing, drying climate, the impact of fire on humans and the hazards faced by our natural and developed world will continue to increase. The increase in wildfire hazards in the twenty-first century will require higher levels of training, increased investments in wildfire personnel and infrastructure, greater wildfire awareness, and improved planning to reduce fire impacts.
Part of the book: Natural Resources Management and Biological Sciences
Grasslands occur on all of the continents. They collectively constitute the largest ecosystem in the world, making up 40.5% of the terrestrial land area, excluding Greenland and Antarctica. Grasslands are not entirely natural because they have formed and developed under natural and anthropogenic pressures. Their importance now is to the variety of ecosystem services that they provide: livestock grazing areas, water catchments, biodiversity reserves, tourism sites, recreation areas, religious sites, wild food sources, and natural medicine sources. An important function of grasslands is their sequestration and storage of carbon (C). Mollisol soils of grasslands have deep organic matter horizons that make this vegetation type almost as important as forests for C fixation and storage. Fire has been and continues to be an important disturbance in grassland evolution and management. Natural wildfires have been a component of grasslands for over 300 million years and were important in creating and maintaining most of these ecosystems. Humans ignited fires over many millennia to improve habitat for animals and livestock. Prescribed fire practiced by humans is a component of modern grassland management. The incidence of wildfires in grasslands continues to grow as an issue as droughts persist in semi-arid regions. Knowledge of fire effects on grasslands has risen in importance to land managers because fire, as a disturbance process, is an integral part of the concept of ecosystem management and restoration ecology. Fire is an intrusive disturbance in both managed and wildland forests and grasslands. It initiates changes in ecosystems that affect the composition, structure, and patterns of vegetation on the landscape. It also affects the soil and water resources of ecosystems that are critical to overall ecosystem functions and processes.
Part of the book: Grasses and Grassland Aspects