Land Use- Parks, Rangelands, Forestry

Public LandsPublic lands are classified by their use and can be used for many different purposes such as grazing, timber production, cropland, recreational use, mineral extraction and preservation. Most public lands can be categorized as:

1. National parks- public lands protected from resource extraction and development but open to nature appreciation and recreation. Yellowstone, Sequoia, Yosemite and Crater Lake are all examples of National Parks.

2. National wildlife refuge- federally protected area that preserves lands and waters for the conservation of fishes, wildlife, and plants of the United Stats. These areas serve as havens for wildlife but also encourage wildlife dependent activities such as hunting, fishing, wildlife observation, photography, environmental education and other public uses (as long as they are compatible with scientific principals of fish and wildlife management)

3. National wilderness areas/preserves- Areas within existing federal lands (national parks, national forests, national wildlife refuges and land managed by the Bureau of Land Management) that are off-limits to development (including the development/use of roads) but are open to hiking, nature study and other low-impact public recreation. Grazing, mining and buildings are prohibited in wilderness areas.

4. National forest- public lands set aside to grow trees, produce timber and protect water quality. Can also be used for livestock forage, water resources, mining, fishing, hunting as well as habitat for fish and wildlife. National forests were established in response to the rampant deforestation. The depletion of the eastern US forests prompted a system of forest reserved—public land set aside to grow trees, produce timber, protect water quality and serve as insurance against scarcities of lumber. National forests cover 8% of the nation’s land area. National forests fall under a policy of multiple use—meaning that the national forests were to be managed for recreation, wildlife habitat, mineral extraction and various other uses, however timber production was most often the primary use. In 1976 Congress passes the national Forest Management Act that mandated every national forest draw up a plan for renewable resource management

5. National Resource land- public land regulated by the Bureau of Land Management that is primarily used for mining, livestock grazing, oil and natural gas extraction

We can also look at how the land is used to classify public lands- Multiple land use- land that can be used for logging, mining, grazing, recreation, hunting, timber harvesting,

mineral/oil extraction and conservation. Examples: National Forests and National Resource lands Moderately restricted land use- National Wildlife Refuges are areas where land is used to protect habitats The

U.S. Fish and Wildlife Service administers the national wildlife refuges, that provide protected habitats for wildlife but also in many cases encourage hunting, fishing, wildlife observation, environmental education and other public uses. They are the only federal lands managed for the primary purpose of protecting wildlife.

Restricted land use- Both National Parks and National Wilderness Areas/Preserves are examples of restricted land use areas. National parks preserve and interpret the country’s historic and cultural heritage (battlefields, memorials, etc) and protect wilderness areas. Parks can be used for camping, hiking, fishing and boating. 49% of the National Park system is wilderness. Threats to National Parks include increased visitors to parks that can bring in non-native species, air pollution, human activities adjacent to the park as well as limited funds available

Worldwide forest usage.

for maintenance. National Wilderness Areas/Preserves are road-less areas in National Parks, Wildlife Refuges or National Forests. They are set aside with the intent of preserving large tracts of intact ecosystems or landscapes and allow limited human use such as hiking, fishing, camping, non-motorized boating, hunting, and horseback riding.

Threats to U.S. ParksAll the problems plaguing urban areas are found in popular national parks during peak seasonal use including crime, vandalism, litter, traffic jams, and pollution of soil, air and water. In addition, thousands of resource violations, from cutting live tress to collecting plants, minerals and fossils to defacing historical structures with graffiti and setting fires, are investigated in national parks each year. Park managers have had to reduce visitor access to environmentally fragile park areas degraded from overuse

RangelandsRangelands are large, dry, undeveloped, open grasslands used primarily for cattle grazing. Rangelands are semiarid ecosystems and are therefore susceptible to fires and other environmental disturbances—they include grasslands, tundras, scrublands, alpine areas and savanna. Rangelands cover 26% of the Earth’s land surface. If humans overuse rangelands, they can easily lose biodiversity. Careful management is required to prevent damage to soil loss as a result of overgrazing. Grazing by animals stimulates grass to grow and remove dead material. However, overgrazing can occur when too many animals are grazed for too long on a section of pasture and the grass does not have enough time between cropping to regrow. Exposed soil may then become colonized by invasive species or eroded by wind or rain. When overgrazing occurs in combination with an extended drought, once-fertile rangeland can be converted to desert. The reduced grass cover caused by over grazing allows winds to erode soil. Even when the rains return, land degradation is so extensive that the rangeland may not recover. Water erosion removed the little bit of remaining topsoil, and the sand left behind forms dunes. This progressive degradation, which induces unproductive desert like conditions on formally productive rangeland (or tropical dry forest) is called desertification. Desertification reduces the agricultural productivity of economically valuable land, forces many organisms out and threatens endangered species. The Taylor Grazing Act was passed in 1934 to halt overgrazing. It converted federal rangelands from a commons to a permit-based grazing system. The Bureau of Land Management manages most public rangelands in the U.S.

Forestry The idea of sustainable forestry followed acknowledgement of the damage done by unrestricted logging of old growth forests. For forestry to be sustainable, demand for timber must be balanced with the regrowth of seedling. Sustainable forestry allows timber demands to be met without over-exploiting the timber-producing trees. Different methods for logging are used depending on the type of forest being logged. This allows the various services provided by forests to remain undisrupted.

Deforestation Deforestation is the clearing and loss of forested areas. It has altered landscapes and ecosystems across much of our planet. As we eliminate some forests and alter others, we lose biodiversity, worsen climate change and disrupt the ecosystem services that support societies. The alteration, fragmentation and outright loss of forested land represent one of our society’s primacy

challenges.

Types of Forests:Old Growth Forests are climax communities. They have remained undisturbed by natural events and human interference for many hundreds of years. Old growth forests are ecologically significant because of their high biodiversity and they are often home to endangered or endemic species. Larger forests also play a part in climate modificationSecond Growth Forests result from secondary ecological succession after a major forest disturbance such as fire or logging. At first, these forests may have quite different characteristics from the original community, especially if particular tree species were removed completely by logging. As the forest develops, the trees are often of the same age so that a single canopy develops.

Commercial plantations/tree farms/tree plantations are specifically planted and grown for the production of timber or timber based products. These forests are virtual monocultures containing a specific timber tree. These trees have often been selectively bred to produce straight trunked, uniform trees that grow quickly and can be easily harvested and milled. Because of their cycle of planting and harvesting, tree plantations never develop into mature, ecologically diver forests. If too many planting and harvesting cycles occur, the soil may become depleted of important nutrients such as calcium.

Examples of Ecosystem ServicesPurification of air and waterPreservation of soil and renewal of soil fertilityPrevention of flooding due to runoff

Regulation of climateMaintenance of biodiversityMovement and cycling of nutrientsAesthetic beauty

Maximum Sustainable Yield

With tree-harvesting, and any type of resource extraction, it is important to know the maximum sustainable yield of the ecosystem. The maximum sustainable yield is the max amount that can be harvested without compromising the future availability of that resource. When we want to obtain the maximum amount of a resource we need to know how much a given plant or animal population can be harvested without harming the resource as a whole. In theory, a population grows at its maximum rate when its approximately half the carrying capacity.

Clear CuttingA section of a mature forest is selected (based on tree height, girth or species) and all the trees are removed. During this process the understory is destroyed. A new forest of economically desirable trees may be planted. In plantation forests, the trees are generally of a single species and may even be genetic clones. Often the entire area will be replanted as the same time, so all the resulting trees will be the same age. Because they are exposed to full sunlight clear clear-cut tracks of land are ideal for fast growing tree species that achieve their maximum growth rates with large amounts of fiect sunlight. Other species may not be so successful, which can lead to a reduction in overall biodiversity. Clear Cutting is a very productive and economical method of managing a forest, however it is also the most damaging to the natural environment. In plantation forests, this may not be of concern and may not affect sustainability, but clear cutting of old growth forests causes enormous ecological damage. Clear-cutting, especially on slopes, increases wind and water erosion, which causes the loss of soil and nutrients. Erosion adds silt and sediments to nearby streams, harming aquatic populations. Clear cutting also increases the amount of sunlight that reaches rivers and streams and the increased sunlight raises the water temperature.

Selective Cutting/LoggingA mature forest is examined, and trees are selected for removal based on height, girth or species. These trees are felled individually and directed to fall in such a way as to minimize the damage to the surrounding younger trees. Mature trees are cut individually or in small clusters while the rest of the forest remains intact to allow the forest to generate naturally. The trees left produce seeds that germinate to fill the void. The forest is managed in such a way as to ensure continual regeneration of young seedlings and provide a balance of tree ages that mirrors the natural age structure.

Seed-tree cuttingIn the seed-tree approach, small numbers of mature and vigorous seed-producing trees are left standing so that they can reseed the logged area. Almost all trees are harvested from an area; a scattering of desirable trees is left behind to provide seeds for the regeneration of the forest.

Shelterwood cutting

In the shelterwood approach, small numbers of mature trees are left in place to provide shelter for seedlings as they grow. These lead to even-aged stands of trees. In the first year of harvest, undesirable trees species and dead or diseased trees are removed. The forest is then left alone for a decade in which the remaining trees continue to grow and new seedlings become established. During the second harvest, many mature trees are moved but some of the largest trees are left to shelter the young trees. The forest is then allowed to regenerate on its own for another decade. A Third harvest removed the remaining mature trees, but by this time a healthy stand of younger trees is replacing the mature ones.

Strip cutting Strip cutting is a type of timber harvesting practice in which a strip of trees is removed that is narrow enough to be naturally re-seeded. The next year a new strip is cut and essentially the forest is clear-cut over a decade which decreases the overall damage.

Slash and BurnSlash and burn agriculture is the process of cutting down the vegetation in a particular plot of land, setting fire to the remaining foliage, and using the ashes to provide nutrients to the soil for use of planting food crops. Places where open land for farming is not readily available because of dense vegetation are the places where slash and burn agriculture is practiced most often. When used properly, slash and burn agriculture provides communities with a source of food and income. Slash and burn allows for people to farm in places where it usually is not possible because of dense vegetation, soil infertility, low soil nutrient content, uncontrollable pests, or other reasons. However, slash and burn agriculture contributes to a number of reoccurring problems specific to the environment such as deforestation, erosion, nutrient loss and loss of biodiversity.Selective cutting, seed-tree, shelterwood, and strip cutting require logging roads to carry equipment and workers to and from. These roads fragment the forest habitat (which leads to changes in species diversity), and they compact the soil (which leads to nutrient loss and reduction of water infiltration).

Ecological Sustainable Forestry The goal to this approach is to maintain all species- plant and animals- in as close to a natural state as possible. Some loggers have even returned to using animals such as horse to pull logs in order to reduce soil compaction, although the costs of such methods make it difficult to compete with mechanized logging practices.

Pros Cons- many plant species require fires for seedling

germination- -destruction of old trees provide light gaps which

encourage young tree growth- regrowth provides food for herbivores- reduce the risk of wild fires

- can be destructive to huge plots of plant and animal species

- can threaten structures- can accelerate erosion

Forest FiresIn many ecosystems, fire is a natural process that is important for nutrient cycling and regeneration. When fires periodically move through an ecosystem, they liberate nutrients tied up in dead biomass. In addition, areas where vegetation is destroyed by the fire can provide openings for early successional species.Prescribed Burns/Controlled Burns are designed to remove excess flammable material in a section of forest, and so significantly reduce the risk of a wildfire. This is done in colder seasons where the risk of the burn becoming uncontrollable is reduced. The controlled burns also help to stimulate new growth. Controlled burns are carried out to prevent small surface fires from becoming crown fires or out of control wildfires. Surface fires burn debris close to the ground and can be of benefit to a forest. Crown fires are large, extremely hot forest fires that often destroy large trees and forest. Ground fires are fires that burn material underground (such as peat) but may emerge to cause surface fires.