Land Use

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Unit VI

• Land Use

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Land Breakdown
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US Land Use

• 55 of land in US is privately owned
• Remaining land is owned by the government
• Most federal land is in Alaska and western states

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Land Use
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Wilderness Parks and Wildlife Refuges

• Wilderness
• A protected area
• of land in which no
• human development
• is permitted
• Wilderness Act
• (1964)
• Set aside federally owned land
• Managed by NPS, USFS, FWS BLM

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National Parks

• 1st Park 1872
• Yellowstone
• National Park Service
• Created in 1916
• Currently includes 58 parks
• Primary goal
• Teach people about the natural environment,
  management of natural resources and history of a
  site

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National Parks

• Threats to U.S. Parks
• Crime Vandalism
• Traffic jams
• Pollution of the soil, water and air
• Resource violations
• Natural Regulation
• Policy to let nature take its course
• No culling wildlife or suppressing wildfire

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Wildlife Refuge

• National Wildlife Refuge System
• First one in 1870
• Lake Merritt, CA
• First National 1903
• Pelican Island
• Represent all major ecosystems found in the US
• Mission
• To preserve lands and waters for the conservation
  of fishes, wildlife and plants of the US

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National Forests

• Managed for multiple uses
• Timber harvest
• Livestock forage
• Water resource and watershed protection
• Mining, hunting, fishing, etc.
• Road building is an issue
• Provides logging companies with access to forest
• Clearcutting is an issue

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Forest Management

• Traditional Forest Management
• Low diversity - monocultures
• Managed for timber production

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Forest Management

• Ecological Sustainable Forest Management
• Environmentally balanced
• Diverse trees
• Prevent soil erosion
• Preserve watersheds
• Wildlife corridors - unlogged

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Harvesting Trees
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Deforestation

• Results of Deforestation
• Decreased soil fertility
• Uncontrolled soil erosion
• Production of hydroelectric power (silt build up
  behind dams)
• Increased sedimentation of waterways
• Formation of deserts
• Extinction of species
• Global climate changes

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Rangelands

• Rangelands
• Land that is not intensively managed and is used
  for grazing livestock

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Rangelands

• Overgrazing leaves ground barren
• Animals exceed lands carrying capacity
• Land degradation
• Natural or human-induced process that decreases
  future ability of land to support crops or
  livestock
• Desertification
• Degradation of once fertile land into
  nonproductive desert

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Rangelands

• Make up 30 of total US land area
• Pressure from developers to subdivide
• Public rangeland managed by
• Taylor Grazing Act (1934)
• Federal Land Policy and Management Act (1976)
• Conditions of public rangeland are slowly
  improving

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Agricultural Land

• US has 300 million acres of prime farmland
• Suburban sprawl
• Parking lots
• Housing
• developments
• Shopping malls

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Food Production Methods

• Croplands
• provides 75 of worlds food supply
• mostly grain production
• Rangelands
• provides 15 of worlds food supply
• includes meat and meat products
• Fisheries
• provides 7 of worlds food supply
• primarily oceanic fishes

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World Food Security

• Feeding growing population is difficult
• Annual grain production (left) has increased
  since 1970
• Grain per person has not (right)

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Crop Production
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Animals as Food

• Constitute 40 of the calories consumed in
  developed countries
• Only comprise 5 of calories consumed in
  developing countries

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Principle Types of Agriculture

• Industrialized agriculture
• Modern agriculture methods that require large
  capital input, and less land and labor
• Uses large amounts of energy, water, fertilizers,
  pesticides
• practiced on 25 of all cropland
• produces 80 of worlds food supplies

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Principle Types of Agriculture

• Subsistence Agriculture
• Traditional agricultural methods, which are
  dependent on labor and large amounts of land
• Most common type of agricultural practice
• practiced by 40 of worlds population
• shifting cultivation, slash and burn agriculture,
  nomadic herding, intercropping

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Challenges of Producing More Crop and Livestock

• Domestication and Genetic Diversity
• Domestication of crops and livestock causes a
  loss of genetic diversity
• Farmer selects and propagates animals with
  desirable agricultural characteristics

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Challenges of Producing More Crop and Livestock

• Increasing Crop Yields
• Food production increased in developed countries
  (wheat(left)
• Pesticides
• Selective breeding

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Challenges of Producing More Crop and Livestock

• Increasing Livestock Yields
• Hormone supplements
• US and Canada
• Not used in Europe
• Antibiotics
• 40 of antibiotics produced in US are used in
  livestock operations
• Problems with increased bacteria resistance

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Antibiotic Use and Resistance
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Genetic Engineering

• Manipulation of genes by taking specific gene
  from a cell of one species and placing it into
  the cell of an unrelated species

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Genetically Modified Organisms (GMOs)

• Add beneficial characteristics to crops
• Additional nutrition
• Resistance to pests
• Drought resistances (below)
• Herbicides

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Genetically Modified Organisms (GMOs)
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Safety in Genetic Engineering

• Studies have shown them to be safe for human
  consumption
• Concerns about GMO seed or pollen spreading in
  wild
• GMOs are not currently labeled
• Push for legislation in certain states or
  communities
• Backlash against GMOs
• Banned in EU

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Environmental Impacts of Agriculture
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Sustainable Agriculture

• Examples
• Natural Predator-prey relationships instead of
  pesticides
• Crop selection
• Crop rotation and conservation tillage
• Supplying nitrogen with legumes
• Organic agriculture
• Integrated Pest Management (IPM)

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Fisheries

• No nation lays claim to open ocean
• Resource susceptible to overuse and degradation
• commons

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Fisheries

• Overharvesting
• Many species are at point of severe depletion
• 62 of worlds fish stock are in need of
  management action
• Sophisticated fishing equipment
• Bycatch killed off

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Commercial Fishing Methods

• Trawling
• Purse-Seine
• Longlining
• Drift Net
• Aquaculture

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World Seafood Harvest
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Fisheries of the World - Problems

• Ocean Pollution - dumping ground
• Oil
• Heavy metals
• Deliberate litter dumping
• Stormwater runoff from cities and agricultural
  areas
• Aquaculture
• Growing of aquatic organisms for human
  consumption
• Great potential to supply food

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Fisheries of the World - Problems

• Aquaculture (continued)
• Locations of fisheries may hurt natural habitats
• Produce waste that pollutes adjacent water

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Pesticides

• Broad spectrum pesticide
• A pesticide that kills a variety of organisms,
  not just the targeted organisms
• 1st Generation Pesticide
• Inorganic compounds
• Botanicals plant derived pesticides (right)

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Pesticides

• Second generation pesticide
• Synthetic poison
• Ex DDT

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Problems with Pesticides

• Evolution of Genetic Resistance
• Pest populations are evolving resistance to
  pesticides (right)

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Pesticide Resistance

• Pesticide Treadmill
• Cost of applying pesticide increases
• While their effectiveness decreases
• Resistance Management
• Strategies for managing genetic resistance in
  order to maximize the period in which a pesticide
  is useful

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Problems with Pesticides

• Imbalances the Ecosystem
• Spraying to kill insects can affect birds,
  rabbits, etc.
• Despite 33-fold increase in pesticides since the
  1940s, crop loss has not decreased much

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Problems with Pesticides

• Persistence, Bioaccumulation, and
  Biomagnification
• Bioaccumulation The buildup of a persistent
  pesticide or other toxic substance in an
  organisms body
• Biomagnication Increased concentration of toxic
  chemicals in tissues of organisms at higher
  trophic levels

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Systems Approach - Integrated Pest Management
(IPM)

• IPM
• Combination of pest control methods that keeps
  pest population low without economic loss
• Conventional pesticides are used sparingly when
  other methods fail

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Integrated Pest Management
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Systems Approach - Integrated Pest Management
(IPM)

• Rice Production in Indonesia

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Manufacture and Use of Banned Pesticides

• Some US companies still make banned or seriously
  restricted pesticides
• Product is exported
• May lead to the importation of food tainted with
  banned pesticides
• Global ban of persistent organic pollutants
• Stockholm Convention on Persistent Organic
  Pollutants POPS (2004)

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Manufacture and Use of Banned Pesticides - The
Dirty Dozen
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International Regulations

• Endangered Species Act- prohibits the harm or
  harvesting of endangered species protects
  habitats
• Marine Mammal Protection Act- protection and
  conservation of marine mammals (whales, dolphins,
  etc)