Send the link below via email or IMCopy
Present to your audienceStart remote presentation
- Invited audience members will follow you as you navigate and present
- People invited to a presentation do not need a Prezi account
- This link expires 10 minutes after you close the presentation
- A maximum of 30 users can follow your presentation
- Learn more about this feature in our knowledge base article
Land and Water Use
Transcript of Land and Water Use
Designed by C. Chigounis 2014, based on
Barrons AP Environmental Science and Miller's Living in the Environmental Text
Areas on Which You Will Be Tested
feeding a growing population (human nutrition requirements, types of agriculture, green revolution, genetic engineering, crop production, deforestation, irrigation, & sustainable agriculture.
Controlling pests - types of pesticides, costs and benefits of pesticide use, integrated pest management & relevant laws.
tree plantations, old-growth forests, fires, forest management, and national forests.
overgrazing, deforestation, desertification, rangeland management, & federal lands.
Other Land Use:
urban development, suburban sprawl, & urbanization
transportation infrastructure - federal highway system, canals, etc..
public and federal lands - management, wilderness areas, national parks, wildlife refuges, forests, & wetlands.
land conservation options - preservation, remediation, mitigation, & restoration.
mineral formation, overfishing, aquaculture, and laws / treaties
fishing techniques, overfishing, aquaculture & laws
globalization, World Bank, "Tragedy of the Commons", laws, etc..
Feeding a Growing Population
Several factors must be considered to adequately feed a population:
Human Nutritional Requirements
avg. male requires 2,500 daily calories
avg. female requires 2,000 daily calories
balanced intake of proteins, fats, & carbohydrates
protein produces 4 calories of energy per gram & should make up 30% of all calories
carbohydrates produces 4 calories of energy per gram & should make up 60% of all calories
fats produce 9 calories of energy per gram and should make up no more than 10% of daily caloric intake.
of 350,000 plants, only 100 species are commercially grown
wheat and rice supply over half of human caloric intake
only 8 species of animals supply over 90& of world's needs
it takes 16 lbs of grain to produce 1 lb of edible meat
20% of the world's richest countries consume 80% of the world's meat production
90% of the grain grown in US goes towards animal feed
If humans ate grain directly rather than used it for feed, there would be a 20-fold increase in calories available and 8-fold increase in available protein
benefits of eating meat products is they provide concentrated source of protein broken down into amino acids via digestion.
Feeding a Growing Population
11 million children die each year from starvation
850 million people (13% of global population) considered malnourished
Chronic undernourishment and vitamin deficiencies result in stunted growth, weakness, and susceptibility to illness
Most undernourished reside in developing countries
are protein deficiency diseases in which victims may become emaciated to the point that they may be be less than 80% of their normal weight for their height.
Types of Agriculture
a system that uses harvestable trees & shrubs among crops or on pastureland as a way of preserving / enhancing productivity of land.
planting crops in strips with rows of trees / shrubs on each side to increase biodiversity, reduce runoff & erosion, improve nutrient, create microclimates, etc.
: rotating different crops on a field from year to year to reduce soil nutrient depletion. ex.) rotating corn or cotton, which removes large amounts of nitrogen from soil, with soybeans (legume), which add nitrogen to soil.
Types of Agriculture
: includes the use of mechanized equipment, chemical fertilizers, and pesticides.
Industrial Agriculture or Corporate Farming
: system characterized by mechanization, monocultures, and the use of synthetic inputs such as chemical fertilizers & pesticides. Emphasis on maximizing productivity and profitability.
: growing more than one crop in the same field, especially in alternating rows or sections
Types of Agriculture
: growing two different crops in an area simultaneously. Plants should have similar nutrient & moisture requirements
dependent upon hand-tools, natural fertilizers; lacks large scale irrigation
Low-Till, No-Till, or Conservation-Till Agriculture:
involves minimal disturbance to soils to reduce erosion. Involves lower labor costs, reduces need for fertilizer, saves energy.
the cultivation of a single crop
: a commercial tropical agriculture system that's essential export oriented. Governments & foreign / International companies exploit the natural resources for profit, usually short-term economic gain. Involves introduction of economically desirable species that replace endemic flora.
Types of Agriculture
use of different crops in the same space; attempts to imitate diversity or natural ecosystems; involves crop rotation, multicropping, intercropping, and alley cropping. Involves more labor but has several advantages over monoculture. Diversity of crops avoids susceptibility of disease wiping out entire harvest. Provides improved habitat for more species, increasing local biodiversity.
: planting a plot of land with several varieties of the
farming carried out for survival - with few or no crop available for sale; usually organic due to lack of funding for fertilizers, pesticides, etc.
: method where surface is plowed to break up and expose nutrients prior to being smoother over and planted. This method exposes surface to water and wind erosion.
1st Green Revolution: occurred between 1950 - 1970; involved:
planting of monocultures
high application of inorganic fertilizers & pesticides
artificial irrigation system
crop acreage increased 25% but yield increased 200%
2nd Green Revolution: began 1970 - present; involved:
uses genetically engineered crops (GMO's)
of all wheat planted today, 50% comes from 9 different genotypes
Green Revolution Criticisms
Critics site the following problems and / or failures:
increased food production not synonymous with increased food security (famines are not caused by decreases in food supply but by socioeconomic dynamics
GR focuses too heavily on monoculture
decrease of land productivity (desertification, land degredation)
bankrupting of smaller farms in favor of industrialized farms
increase use of pesticides, herbicides, etc.
salinization, water logging, , and lowering of water table due to increased irrigation
reduction of agricultural biodiversity due to reliance on high-yield varieties equating to higher susceptibility to pathogens, etc.
Genetic Engineering and Crop Production
: moving genes from one species to another or designing gene sequences with desirable characteristics.
examples: pest, drought, mold & saline resistance, higher protein yields, and higher vitamin content.
75% of all crops harvested derive from genetically engineered or transgenic crops.
majority are herbicide and insect resistant soybeans, corn, cotton, canola, and alfalfa .
others include: virus resistant sweet potato, iron & vitamin rich rice (golden rice), weather-resistant plants.
future potential: fish that mature faster, bananas able to transmit hepatitis B vaccines, early yielding fruit and nut trees, plastic producing plants, etc.
: golden rice is produced by splicing 3 foreign genes; two from the daffodil and one from a bacterium, into a variety of rice that supplies vitamin A to populations that frequently suffer from vitamin A deficiency.
Genetic Engineering & Crop Production
Genetically Engineered Crops - Pros & Cons:
: may require less water & fertilizer, higher crop yields, less spoilage, faster growth, drought, disease, frost, and insect resistance, ability to grow in saline soils
unknown ecological effects, less biodiversity, may harm beneficial insects, allergen risk, mutations with unknown consequences, creation of pesticide resistant strains.
3/4 of all freshwater on Earth used for agriculture
globally, 40% of all crop yields come from 16% of all cropland that is irrigated
use of irrigation dependent on climate and stage of industrialization
ex) Canada irrigates 10% of crops whereas India irrigates 90%
up to 70% of irrigation lost via seepage, leakage, evaporation
Drip Irrigation System used on only 1% of global crops
involves variety of approaches and integrates three main goals:
social & economical equity
Strategies must consider the following:
local availability of inputs
individual grower's goals
decline of family farms
poor working conditions for laborers
increasing costs of production
disintegration of economic conditions in rural communities
Efficient Use of Inputs
sustainable farmers maximize reliance on natural, renewable farm inputs with goal to develop efficient, biological systems that don't require high levels of material inputs. Sustainable approaches are those that are least toxic and least energy intensive but still maintain productivity and profitability. Preventive strategies such as Integrated Pest Management (IPM) should be used prior to consideration of chemical inputs.
Selection of Site, Species, and Variety:
pest-resistant crops should be used
tolerance of soil and site conditions preferable
soil type, depth, previous crop history, location (climate & topography) should be taken into account prior to planting
proper soil, water, & nutrient management can prevent some pest problems that occur when plants are stressed
crop management that impairs soil will result in greater inputs of water, nutrients, pesticides and / or energy for tillage
sustainable systems view soil as living medium that must be nurtured to ensure long-term productivity
methods of enhancement include: cover crops, compost, and / or manures, reducing tillage, and maintaining soil cover with plants and / or mulches.
regular additions of organic matter to sustain microbial life imperative
by growing variety of crops, farmers reduce economical risk if one type of crop were to fail
this strategy also insures against radical price fluctuations associated with changing supply and demand
cover crops can have stabilizing effects on the agro-ecosystem by retaining soil nutrients, conserving moisture and increasing water infiltration rate and soil water-holding capacity
optimum diversity achieved by integrating crops and livestock in the same farming operation (livestock provide manure)
Types of Pesticides
Pesticides differ in several ways:
environmental persistence (how long they last in the environment)
impact on food web (bioaccumulation & biomagnification)
types of organisms impacted
how pesticide works (nervous system, reproductive cycle, blood chemistry)
how fast they work
method of application
Types of Pesticides
the use of living organisms to control pests.
ex) bacteria, Bt (
), ladybugs, milky spore disease, parasitic wasps, and certain viruses.
Bt is a soil dwelling bacterium that occurs naturally in the gut of caterpillars or several moth and butterfly species, as well as on dark surface of plants. Proteins produced by Bt are used as specific insecticides. They work by secreting one or more toxins after being ingested by an insect.
Advantages of using Bt
level of toxin can be very high, thus delivering sufficient dosage to the pest
contained within the plant system therefore only those insects that feed on the crop perish
replaces the use of synthetic pesticides in the environment
aka (urethanes), affect the nervous system of pests. 100 grams of a carbomate has the same effect as 2,000 grams of a chlorinated hydrocarbon such as DDT. Carbamates are more water soluble than chlorinated hydrocarbons, which brings a greater risk of them dissolving in surface water and percolating into groundwater.
: on December 2nd, 1984 at the Union Carbide pesticide plant in Bhopal India, a leak of chemicals from a plant manufacturing carbamate pesticides leaked, resulting in the exposure of hundreds of thousands of people; roughly 8,000 people have since died from gas-related diseases with 200,000 people having permanent injuries.
Chlorinated Hydrocarbons and Other Persistent Organic Compounds (POPS):
synthetic organic compounds belonging to a group of chemicals known as persistent organic pollutants or POP's.
Pops are resistant to environmental degradation through chemical, biological, and photolytic processes
Consequently, they're capable of long-range transport, bioaccumulation in tissue, biomagnify in food chains & pose significant impacts on human health and the environment.
POP's were / are used as pesticides, used in industrial processes, and in the production of good including solvents, polyvinyl chloride (PVC), and pharmaceuticals.
Chemical characteristics of POP's include: low water solubility, high lipid solubility, semi-volatility, and high molecular masses.
Pop's are frequently halogenated, usually with chlorine.
The more chlorine or other halogen groups a POP has, the more resistant it is to being broken down over time.
Lipid solubility allows POPs to pass through biological phospholipid membranes and bioaccumulate in fatty tissue.
Semi-volatility allows them to travel long distances through the atmosphere before being deposited, making them prevalent in areas where they've never been used.
Semi-volatility also means that they volatilize in hot regions and accumulate in cold regions, where they tend to condense and persist.
As a pesticide, they impact the nervous system (neurotoxin). In 1950's DDT was linked to the thinning of eggshells in certain species of birds (e.g. bald eagles)
: used to sterilize soil and prevent pest infestation of stored grain.
broad-based pesticides. Includes arsenic, copper, lead, and mercury. Highly toxic and accumulate in the environment.
Organic or Natural
: natural poisons derived from plants such as tobacco or chrysanthemum.
: extremely toxic but remain in the envrionment for only a brief time. Examples include malathion to control mosquitoes and West Nile Virus, and parathion.
Costs and Benefits of Pesticide Use:
Despite the use of pesticides, many pests worldwide have increased in numbers due to genetic resistance, reduced crop rotation, increased mobility of pests due to global trade, and reduction of crop diversity
Pros and Cons of Pesticides:
: kill unwanted pests that carry disease, increase food supply; more food means less costly, newer pesticides are safer and pest-specific, reduces labor costs, agriculture is more profitable.
accumulate in food chains, development of resistance, $5 - $10 in damage done for every $1 spent on pesticides, expensive, runoff impacts aquatic organism, inefficiency - only 5% of a pesticide reaches a pest; threatens endangered species and impact human health.
Integrated Pest Management
Integrated Pest Management (IPM):
pest control strategy that uses a variety of methods in combination to reduce or eliminate the use of traditional pesticides. Aim of IPM is NOT to eradicate pests but to control their numbers to acceptable levels. Chemical pesticides are a LAST resort in IPM.
Methods employed in IPM include:
planting pest-repellent crops
using mulch to control weeds
using pyrethroids or naturally occurring microorganisms (Bt) instead of toxic pesticides
natural insect predators
crop rotation to disrupt insect cycles
use of pheromones or hormone interrupters
releasing sterile insects
using genetically modified pest resistant crops
construction of traps, use of tillage, insect barriers, or agricultural vacuums equipped with lights
Federal Insecticide, Fungicide, and Rodenticide Control Act (FIFRA) (1974)
: regulates the manufacture and use of pesticides. Pesticides must be registered and approved. Labels require directions for use and disposal.
Federal Environmental Pesticides Control Act (1974):
requires registration of all pesticides in US commerce.
Food Quality Protection Act (FQPA) (1996):
emphasizes the protection of infants and children in reference to pesticide residue in food.
forestry involves the management of forests. Sometimes this involves planting new trees, and sometimes it involves fires.
providing wildlife habitats
affecting local climate patterns
purifying air and water
reducing soil erosion
providing energy and nutrient cycling
large,managed commercial or government owned farms with uniformly aged trees of one species (monoculture) to be used for pulp and / or lumber. Pine, spruce, and eucalyptus widely used due to fast growth and use for paper and lumber. Harvesting done via clear-cutting. Short rotation cycles (25-30 years) or 6-10 years in tropics are critical factors. 63% of global forests are secondary forests and 22% are old growth forests.
Annually, tropical tree plantations yield more wood than traditional forests. Some natural closed forests (7%) are being lost in tropics due to land conversion to tree plantations. Tree plantations do NOT support food webs found in old growth forests and contain little biodiversity. Decaying wood is absent. Conversion to tree plantations may result in draining wetlands and replacing traditional hardwood forests. New techniques leave areas for native species within the plantation or retaining wildlife corridors. Kyoto Protocol encourages use of tree plantations to reduce carbon dioxide.
: forests that have not been seriously impacted by human activities for hundreds of years. They are rich in biodiversity.
older with mixed trees
minimal human activity
multilayered canopy opening due to tree falls
Pit-and-mound topography due to tree falls which create new microenvironments
decaying wood & ground layer provides rich carbon sink
dead trees (snags) used for nesting woodpeckers & spotted owls
healthy soil profiles
indicator species present
little vegetation on forest floor due to limited light
Depletion of old-growth forests increases risk of climate change. Many old-growth forests contain tree species with high economic value but that require long time to mature (mahogany, oak, etc.)
Present wildfire frequency in US is about 4 times the average (1970 - 1986) and total area burned by current fires is 7 times its previous level.
US Forest Service has lengthened wildfire season by 78 days as a result of longer & warmer summer and early spring snowmelt.
As forests burn, they release stored carbon as carbon dioxide into atmosphere, exacerbating global warming.
Another reason for increase in forest fires is change in fire management philosophy - any naturally started fire on federal land that doesn't threaten resources (homes & commercial structures) is allowed to burn.
occur in forests that have not had surface fires for an extended time. Extremely hot, burn entire trees and leap from treetop to treetop. Kills wildlife, increases soil erosion, & destroys structures.
occur underground and burn partially decayed leaves. Common in peat bogs. Difficult to extinguish.
burns undergrowth and leaf litter, kills seedlings and saplings, spares older trees and allowed many wildlife to escape. Advantages: burns away flammable ground litter reducing larger fires later, recycles minerals to soil, stimulates germination of conifers (giant sequoia & jack pine), reduces pathogens and pests, allows vegetation to establish, providing food for deer, elk, moose, muskrat, and quail.
Methods to Control Fires:
two methods employed: prevention & prescribed burning
involves burning permits, closing portions of forest when # of visitors is high, during periods of drought, and educating public.
involves purposely setting controlled surface fires to thin out underbrush in high-risk areas; requires careful planning and monitoring.
the conversion of forested areas to nonforested areas.
often used as grasslands for livestock grazing, grain fields, mining, petroleum extraction, fuel wood cutting, commercial logging, tree plantations, & urban sprawl
natural deforestation caused by tsunamis, forest fires, volcanic eruptions, glaciation, & desertification
results in degraded environment with reduced biodiversity. threatens the extinction of species with specialized niches, reduces habitat for migratory species of birds, butterflies, decreases soil fertility (erosion), allows runoff into aquatic ecosystems.
increases carbon dioxide (reduced photosynthesis)
contributes to forest fragmentation
Methods Employed to Manage / Harvest Trees:
maintain a stand with trees of all ages
specific trees in an area are chosen and cut
cutting and removing only largest / best trees
removes all mature trees in an area within a limited time
Seed tree cutting:
majority of trees removed except for scattered, seed producing trees used to regenerate a new stand
all of the trees are cut at the same time. This technique is sometimes used to cultivate shade-intolerant species
clear cutting a strip of trees that follows the land contour. Corridor is allowed to regenerate
Virgin Forests - Past & Present
Deforestation & Hydrological Cycle:
shrinking forest cover lessens landscape's capacity to intercept, retain, and transport precipitation
instead of trapping precipitation, which then percolates to groundwater systems, deforested areas become source of runoff. This faster transport of surface waters translates into flash floods
deforestation also contributes to decreased evapotranspiration due to loss of plants
Deforestation - Philosophies
Three Schools of Through exist:
major cause of deforestation is the growing number of poor.
major cause is "open-access" property rights.
major cause is due to entrepreneurs.
Forests cover about 1/3 of all land surface worldwide
80% of these forests are closed canopies (tree crowns covering more than 20% of the ground)
20% are classified as open canopy (tree crowns covering less than 20% of the ground surface
70% of forests are located in US, Russia, and South America
In US, largest area of timbering is in Pacific Northwest (150,000 people /$7 billion dollar industry)
Forests make up 1/3 of land in US; of 747 million acres of US forest, 2/3 (500 million acres) are nonfederal
Forest Service established in 1905 as agency of the US Department of Agriculture - manages public lands in national forests and grasslands.
Resources used for logging, farming, recreation, hunting, fishing, oil & gas extraction, watersheds, mining, livestock grazing, farming, and conservation purposes.
Forest Service protects and manages natural resources on National Forest System lands, provides community assistance with state and local governments, forest industries and private landowners to help protect nonfederal forests, associated ranges, and watersheds.
Wilderness Act (1964):
created legal definition of wilderness in US. Includes 4 agencies: National Park Service, US Forest Service, US Fish & Wildlife Service, and Bureau of Land Management.
Wild and Scenic Rivers Act (1968):
preserves and protects certain rivers with outstanding natural, cultural, and recreational values in free-flowing conditions for the enjoyment of present and future generations. Classified rivers as wild, scenic, or recreational.
rangelands are being compromised by overgrazing and desertification. The federal government is trying to manage and sustain rangelands.
occurs when plants are exposed to grazing for extended periods without sufficient recovery time.
type of "Tragedy of the Commons"
when plants overgrazed, divert energy from roots for regrowth, causing roots to die back
root die-back does not add organic matter to soil, increasing soil porosity, infiltration rate, and soil's moisture holding ability
overgrazing can reduce root growth by up to 90%
less productive pastures
depletion of organic matter
decrease of soil porosity
increase of soil compaction
moisture-holding capacity reduced
opportunistic weeds thrive
thermal pollution of water bodies increases
eutrophication occurs due to manures entering water bodies
the conversion of marginal rangeland or cropland to a desert-like land type.
overuse of available resources (nutrients & water
1) overgrazing results in animals eating plant life
2) rain washes away trampled soil
3) wells, springs, etc. dry up
4) remaining vegetation dries up or taken for firewood
5) weeds unsuitable for grazing take over
6) ground becomes unsuitable for seed germination
7) wind and dry heat blow away topsoil
Federal Rangeland Management
Rangelands compromise 40% of the landmass in US
dominant type of land in arid and semiarid regions
80% of land in Western US classified as rangelands / only 7% of land on East Coast fit this classification
provide valuable feeding land for livestock and wildlife
serve as source of high-quality water, clean air, and open space
benefit people for recreation, agriculture, mining, and living communities
Rangelands serve multiple purposes:
habitat for game and non-game species
habitat for diverse and wide array of native plant species
source of high quality water, clean air, and open spaces
setting for hiking, camping, fishing, hunting, and nature experiences
foundation for low-input, fully renewable food production systems for cattle industry
Jurisdiction of public grazing rangelands is coordinated through the Forest Service and the Bureau of Land Management (BLM). Prior to 1995, grazing policies were determined by rancher advisory boards composed of permit holders. After 1995, resource advisory councils were formed made up of diverse groups representing different viewpoints and interests. 40% of all federal grazing permits are owned by 3% of all livestock operators.
Methods of Rangeland Management Include:
1) Controlling the # and distribution of livestock so that the carrying capacity is not exceeded
2) Restoring degraded rangeland
3) Moving livestock from one are to another so rangeland can recover
4) Fencing off riparian (stream) areas to reduce damage to sensitive areas
5) Suppressing growth of invasive species
6) Replanting barren rangeland with native grass seed to reduce soil erosion
7) Providing supplemental feed at selected sites
8) Locating water holes, water tanks and salt blocks at strategic points that do not degrade environment
In US, there are more than 76 million residential buildings and 5 million commercial buildings.
These buildings use 1/3 of all energy and 2/3 of all electricity consumed in US.
Energy requirements of buildings account for 1/2 of sulfur dioxide emissions, 1/4 of nitrous oxide emissions, and 1/3 of carbon dioxide emissions.
Green building & city characteristics focus on whole-system approaches including:
energy conservation through government and private industry rebates and tax incentives for solar and other less-polluting forms of energy
resource-efficient building techniques and material
indoor air quality
water conservation through use of xeriscaping
minimize waste through use of recycled materials
locating buildings near public transportation hubs
creating pedestrian friendly parks, greenbelts, and shopping areas
preserving historic and cultural aspects
Suburban Sprawl & Urbanization
the movement of people from rural areas to cities and changes that accompany this migration
Nations with most rapid increase in urbanization rates are usually those with most rapid economic growth
Asia and Africa experiencing greatest growth in urbanization
Reasons behind Urbanization:
access to jobs
higher standards of living
easier access to healthcare
mechanization of agriculture
access to education
Urbanization - Pros & Cons:
uses less land
better educational delivery
mass transit systems
better sanitation systems
recycling more efficient
higher tax revenue
attract industry (jobs)
point source pollutants easier to control
impact on land more concentrated
longer commuting times (traffic)
sanitation systems deal with greater volume
landfill space limited and costly
poverty and emigration of wealthy
higher crime rates
Projected Global Urban Growth
Transportation can be via roadways or water channels. Areas lacking transportation infrastructure suffer economic impact.
Federal Highway System:
FHS contains 160,000 miles or roadway
Important to economies, defense, and mobility
Interstate highways funded in part of Federal government / they're owned, built, and operated by States in which they're located
Current FH tax includes an 18-cents per gallon tax on gasoline, 25-cents per gallon tax on diesel, and a tax on heavy vehicles
FHS serves all US cities - interstate systems go through downtown areas, facilitating urban sprawl (unique to US)
FHS can contribute to:
less pollutants (less stop-and-go traffic)
reduction of GHG
improve fuel economy and reduce foreign oil dependence
improve economy (interstates return $6 in economic productivity for every $1 invested)
improve quality of life (access to goods & services - think amazon.com)
Canals & Channels
Channel (aka "strait"):
defined by relatively narrow body of water that connects two larger bodies of water.
can occur naturally or be constructed
repeated dredging is often necessary due to silting
in US, channels frequented by ships maintained by the US Dept of Interior and monitored by USCG
Two largest canals: Panama Canal & Suez Canal:
Panama Canal: connects Atlantic & Pacific Oceans
allows for travel without circumnavigating South America
Suez Canal connects Red Sea with Mediterranean
allows for travel between Europe and Asia without traveling around Africa
places where no roads have been constructed and as result, no logging or other development can occur.
serve as haven for fish and wildlife due to lack of forest fragmentation
provide habitat for more than 1,600 threatened, endangered, or sensitive plant & animal species
include watersheds & supply clean drinking water
roadless rule protects 60 million acres (31%) of National Forest System lands - about 2% of the total land base in US.
Public & Federal Lands
The Federal government manages public lands, setting aside areas as national parks, wildlife refuges, and wetlands
Bureau of Land Management (BLM)
responsible for managing 262 million acres, including additional 300 million acres of subsurface mineral resources, and 400 acres dedicated to wildlife management.
Most of land managed is located in western US & Alaska
dominated by grasslands, forests, high mountains, arctic tundra, and deserts
BLM manages energy & minerals, timber, forage, wild horse and burro populations, fish and wildlife habitats, wilderness areas, archeological, paleontological, and historic sites.
there are over 1,100 national parks in wold today
many do not receive proper protection from poachers, loggers, miners, or farmers due to costs involved
in US, parks encompass 84 million acres, of which 4 million acres remain privately owned
largest national park in Alaska (makes up more than 16% of the entire park system)
threatened by high demand, large # of visitors, off road vehicles, invasive species, commercial activities (mining, logging, livestock grazing, urban development)
Solutions to these problems:
reduce private land within national parks through incentives to current owners
set quotas for visitation through advanced reservation systems
adopt fees to cover external costs
ban off-road vehicles, cars (replace with shuttles)
conduct periodic & detailed wildlife and plant inventories
Wilderness Act (1964):
wilderness was defined by its lack of noticeable human modifications or presence. Federal officials are required to manage wilderness areas in a manner conductive to retention of their wilderness character.
Wild & Scenic Rivers Act (1968):
established a system of areas distinct from the traditional park concept to ensure the protection of each river's unique environment. Also preserves certain selected rivers that possess outstanding scenic, recreational, geological, cultural, or historic values and maintains their free-flowing condition.
Food Security Act (1985):
also known as "swampbuster", this act contains provisions designed to discourage the conversion of wetlands into non-wetland areas. The act also created a system for farmers to regain lost federal benefits if they restored converted wetlands.
in 1903, President Theodore Roosevelt designated Pelican Island (5 acres) as the first national wildlife refuge, designed to protect breeding birds.
before leaving office in 1909, Roosevelt designated another 52 wildlife refuges
initial wildlife refuges created to protect wildlife (bison, egrets, waterfowl, etc.) from market hunters
during drought years of Great Depression, wildlife refuges were established to protect waterfowl
today National Wildlife Refuge System consists of more than 547 refuges and more than 93 million acres
managed by the US Fish and Wildlife Service
areas that are covered b water (all or part of the year) and support plants that can grow in water-saturated soil.
high plant productivity supports rich diversity of animal life
Canada, Russia, and Brazil contain most wetlands of all countries
global wetlands reduced from 10% of land to 5%
most wetlands in US occurs in FL and Louisiana
90% of wetlands lost to agriculture and urbanization
1/3 of all endangered species in US spend some of their life cycle in wetlands
wetlands serve as natural purification systems, remove sediment, nutrients, and toxins from water
wetlands reduce erosion from storm surges
wetlands with continuous sources of groundwater rich in magnesium and calcium, which make a fen very alkaline (hard water).
groundwater comes from glaciers that have melted, depositing their water in layers of gravel and sand
the water sits upon layers of soil (glacial drift) that are not permeable, thus allowing it time to absorb minerals
type of wetland that accumulates acidic peat, a deposit of dead plant material that can be dried and burned for fuel.
located in cold, temperate climates, usually in boreal biomes such as Siberia, Ireland, Canada, Minnesota, and Michigan.
generally low in nutrients and highly acidic
carnivorous plants have adapted to these conditions by using insects as their nutrient source
wild or primitive portions of national forests, parks, and wildlife refuges where timbering, most commercial activity, motor vehicles, and human-made structures are prohibited.
The Wilderness Act (1964): created the National Wilderness Preservation System, that unites all individual wilderness areas and encompasses a wide variety of ecosystems throughout the country including swamps in the Southeast, tundra in Alaska, snowcapped peaks in the Rockies, hardwood forests in the Northeast, and deserts in the Southwest.
Land Conservation Options
Preservation, remediation, mitigation, restoration, and sustainable land use strategies are land conservation options. Several principles can be employed:
Land-Use Ethic Model:
1) protect biodiversity, habitat, etc. through monitoring and enforcement
2) adopt a user pay approach for the extraction of resources from public lands
3) institute fair compensation for resources extracted from public lands
4) require responsibility for those who damage public lands
5) adopt uneven-aged management to maintain trees at different sizes
6) include ecological serves of trees in estimating their "worth"
7) reduce road building in protected areas
8) let fallen timber remain for habitat
9) grow timber on longer rotations
10) reduce or eliminate clear-cutting, shelter wood cutting, or seed tree cutting on sloped land
11) reduce fragmentation of forests
12) certify lumber cut is done sustainably
13) use sustainable techniques for tropical forests
14) zoning, permitting, etc. of urban land use
Land Conservation Options
Land Conservation Options
Preservation or Sustainable:
to keep or maintain intact
are private, non-profit organizations that work to conserve land by undertaking or assisting in land or conservation acquisition.
the act of correcting fault or decifiency.
ex) Cleanup from the 1989 Exxon Valdez Alaskan oil spill or from the 2010 BP Deepwater Horizon Gulf oil spill.
to moderate or alleviate in force or intensity
ex) Numerous vehicle -deer collisions in Georgia led officials to implement a system of wildlife warning reflectors along local roads. The county installed several thousand reflectors to freeze deer in place before approaching roadways, which reduced mortality and saved motorists thousands of dollars in collision costs.
to restore to its former good condition. Ecosystem restoration involves management actions designed to facilitate their recovery or reestablishment of native ecosystems.
ex) removing a dam, which will allow native fish to a river or the removal of harmful, invasive species from a riparian environment
Overview of Mining
removing mineral resources from the ground. Can involve
underground mines, drilling, room-and-pillar mining, long-wall mining, open pit, dredging, contour strip mining, and mountaintop removal
removing ore from gangue; involves transportation, processing, purification, smelting, and manufacturing
involves distribution to end user
ENVIRONMENTAL EFFECTS & ISSUES
mine wastes - acids and toxins
displacement of native species
reclamation of land and recycling
pollution (air, water, soil, and noise)
human health concerns, risks, and
Factors that determine whether or not to mine an area:
current price of product
amount of ore at site
concentration of ore
type of mining required
cost of transportation
cost of reclamation
samples taken from an area to determine quality and quantity of minerals in location. Roads & equipment brought in
3 main methods exist:
soil and rock overlying mineral deposit (known as overburden) is removed and stored (spoilbank); used where deposits of mineral found near surface
Five forms of Surface Mining:
open pit mining:
most commonly used method to mine coal & tar sand
involves mining a seam of minerals by first removing strip of overburden
removes overburden above mineral seam, leaves behinds terraces and mountainsides
extracts rocks or minerals from earth from an open pit
used to bring up underwater mineral deposits
cheap method; also employed to remove sediment from waterways for boat traffic
uses mining machine driven under remote control into the seam exposed by previous open-cut operations
continuous hauling system transports coal from mine to open-air installation for stockpiling and transport
Mining - Continued
large shafts used to dig Earth
less surface destruction & waste rock production than surfacing mining
occurs below water table
water must be constantly pumped out of mine to prevent flooding
when mine abandoned, water pumped back in, creating acid rock drainage
acid rock drainage:
caused by bacterial decomposition of metal sulfide ions exposed to air
small holes drilled into the site
water based solvents used by minors to extract resources
less expensive since rocks aren't broken or removed
shorter lead times to production
requires less surface ground disturbance
fluids injected into earth toxic and enter groundwater supply
Terms to Know:
a solid fuel made by heating coal in the absence of air so that VOC's are driven off
a mineral added to the metals in a furnace to promote fusing or to prevent the formation of oxides
waste matter separated from metals during smelting or refining of ore
involves chemical processing during smelting
removing metal fro its ore
accomplished by heating beyond melting point with reducing agents (coke or oxidizing agents like air)
(oxygen compound ores: iron, zinc, lead oxide is smelted in a blast furnace at high temp (reduction smelting.
oxide attached to metal combines with with carbon in coke, escaping as CO or CO2
other impurities removed by adding flux
sulfide mineral ores: copper, nickel, lead, or cobalt sulfides, oxygen is introduced to oxidize the sulfide to sulfur dioxide and iron to slag, leaving the metal
Cyanide Heap Leaching:
gold ore is heaped into large pile
cyanide solution sprayed on top of pile
cyanide percolates downward and gold leaches out to bottom
gold removed and liquid cyanide waste are kept in tailing ponds, eventually leaking and entering groundwater
material left over after separating metals, etc. from ore
represent external cost to mining
in coal and oil sand mining, tailings refers to fine waste suspended in water
Gold & Copper Mining
two billion tons of minerals extracted & used annually in the US (about 10 tons for every American
US imports more than 50% of most needed minerals
As mineral reserves become depleted, lower grades of ore are mined, requiring more processing & more pollution
US, Germany, & Russia represent 8% of global population yet consume 75% of most widely used metals (US consumes 20%)
General Mining Law (1872)
: grants free access to individuals and corporations to prospect for minerals in public domain lands and allows them, upon making a discovery, to stake claim on that deposit
Mineral Leasing Act (1920
): authorizes and governs leasing of public lands for developing coal, petroleum, natural gas, and other hydrocarbons, phosphates, and sodium in the US. (Prior to this act, these materials were subject to mining claims under the General Mining Act of 1872)
Surface Mining Control and Reclamation Act (1977)
: established a program for regulating surface coal mining and reclamation activities.
: use of a funnel-shaped net that is dragged along the bottom of the ocean to catch benthic species (shrimp, cod, flounder, scallops, etc.) Analogous to clear-cutting forests. Unwanted species referred to as
extremely long nets are hung down in water where wandering fishes, etc. get caught in them. Notorious for catching turtles, seabirds, & marine mammals. During the 1980's, 10,000 dolphins and whales and millions of sharks were inadvertently killed each year using this method. 1992 UN voluntary ban on drift nets longer than 1.5 miles has had some progress.
placing very long lines with thousands of baited hooks in effort to land swordfish, tuna, sharks, halibut, and cod. Endangers sea turtles, pilot whales, and dolphins.
surrounding large schools of fish spotted by aircraft with a large net. Net is then drawn tight. Tuna, mackerel, anchovies, and herring are targeted.
historically, ocean viewed as unlimited resource
ocean productivity is generally low
light restricted to photic zone
oceans supply 1% of all human food / represent 10% of world's protein source
China responsible for 1/3 of all ocean fish harvesting
1/3 of total catch is fish used for other purposes than consumption:
another 1/3 of global catch is bycatch (fish, mammals, etc. snared in nets & discarded with no commercial value)
maximum sustainable yield (MSY) is the largest amt. of marine organisms that can be continuously harvested without causing population crash
yield generally occurs when a population is maintained at half the carrying capacity
Sustainable Fisheries Management Methods:
regulate locations & numbers of fish farms & monitor pollution output
encourage production of herbivorous fishes
require & enforce labeling of fish products raised / caught with sustainable methods
set catch limits (quotas) far below max. sustainable yield
eliminate government subsidies for commercial fishing
prevent importation of fish from foreign countries not practicing sustainable methods
place trade sanctions on foreign countries not respecting marine habitat, including countries that hunt whales
access fees for harvesting fish and shellfish from public waters
increase number of marine sanctuaries and no-fishing areas
increase penalties for improper fishing techniques, violations, etc.
ban the throwing back of bycatch
monitor & destroy invasive species transported by ship ballast
Methods to Restore Suitable Habitats for Freshwater Fishes:
plating native vegetation on stream banks
rehabilitating in-stream habitats
controlling invasive species
restore fish passages around human-made impediments
regulating & enforcing recreational & commercial fishing
protecting coastal estuaries & wetlands
Aquaculture (aka Mariculture when saltwater species are farm raised) or "Fish Farming"
: the commercial growing of aquatic organisms for food.
involves stocking, feeding, and harvesting
aquaculture growing 6% annually & provides 5% of total food worldwide
mostly taking place in developing nations
most popular farmed products: seaweed, mussels, oysters, shrimp, fish (salmon, trout, catfish, & tilapia)
kelp makes up 17% of aquaculture output (used as food product and additive)
aquaculture used to raise 80% of all mollusks, 40% of all shrimp, and 75% of all kelp
in order to be profitable, species must be marketable, inexpensive to raise, disease resistant, trophically efficient, and marketable within 1 to 2 years
Aquaculture Advantages over Raising Lifestock:
cold-blooded organisms convert more feed to useable protein
for every hectare ocean, intense oyster farming can produce 58,000 kg or protein whereas natural raised oysters produce 10 kg of protein
aquaculture creates dense monocultures that reduce biodiversity and require high nutrient inputs
creates widescale destruction of natural habitats, leaving nutrients & antibiotics in waste-water
potential release of non-native species & disease into adjacent bodies of water, impacting native fauna
requires foraging fish to be used as fish meal to sustain farm-raised species - this fish meal STILL comes from the ocean!
Polychlorinated biphenyls (PCBs) were banned in the US in the late 1970's and are slated for global phase-out under the UN treaty on persistent organic pollutants. PCB's are highly persistent and have been linked to cancer and impaired fetal brain development. Salmon farming has made salmon the third most popular fish in America and comprises 22% of all retail seafood counter sales. Many consumers eat more salmon today to avoid over-consumption of beef and poultry, and to benefit from anti-cancer and anti-heart disease properties of oily fish. However, analysis of US government data found that salmon are likely the most PCB-contaminated protein source in the current US food supply. Approximately 800,000 US adults have an increased cancer risk by eating PCB-contaminated salmon. Farmed salmon are fattened with ground fishmeal and fish oils that are high i PCB's. As a result, salmon farming operations that produce inexpensive fish unnaturally concentrate PCBs. Furthermore, farmed salmon contains 52% more fat than wild salmon, according to the US Dept. of Agriculture.
Anadromous Fish Conservation Act (1965):
authorizes the Secretary of the Interior to enter into agreements with states and other non-federal interests to conserve, develop, and enhance the anadromous fish (fish that migrate from the sea to fresh water to spawn ex. salmon) resources of the US.
Magnuson Fishery Conservation & Management Act (1976):
governs marine fisheries management in US federal waters. Aides in development of the domestic fishing industry by phasing out foreign fishing. To manage fisheries and promote conservation, the Act created 8 regional fishery management councils. The 1996 amendments focused on rebuilding overfished fisheries, protecting essential fish habitat, and reducing bycatch.
UN Treaty on the Law of the Sea (1982):
defines the rights and responsibilities of nations in their use of the world's oceans, establishing guidelines for businesses, the environment, and the management of marine natural resources.
economy & environment linked
environment contains resources used in economy
use of resources for economic purposes creates new environmental situations
occurs via increasing available supply of materials, opening land to production, transporting resources from locations where they're in surplus to areas of shortage
continued increases in living standards for developing nations will increase pressure on planet's carrying capacity
source of financial and technical assistance to developing countries around the world.
owned by 184 member countries
provides low-interest loans, interest free credit, & grants to developing countries for education, health, infrastructure, communications, and environmental issues
in 2001, Board of Directors created plan to guide actions in environmental areas
strategy emphasized 3 objectives:
improving quality of life
improving quality of growth
protecting vulnerable resources deemed as "commons"
in 2005, World Bank had distributed 13.8 billion in public & private funds in areas of biodiversity, conservation, climate change, & international waters
funded $740 million in projects to phase out ozone-depleting substances & funded $1.6 billion into projects that reduce greenhouse gas emissions
World Bank is greatest single source of funds for large dam projects - since 1948, these large dams have forcibly displaced 10 million people from their land
Tragedy of the Commons
Originally written by Garrett Hardin in 1968 in journal
story parallels what's happening globally in regard to resource depletion & pollution
seas, air, water, animals, & minerals are all commons
all are for human use
those who exploit them become rich
price of depleting resources of the commons is external cost paid by all people on Earth
Examples of "tragedy of the commons" include:
uncontrolled human population growth
overextraction of groundwater
frontier logging of old growth forest and slash & burn
burning of fossil fuels & consequential global warming
habitat destruction & poaching
Limits to the "Tragedy of the Commons" Include:
economic decisions generally short-term
based on reactions in world market
environmental decisions are long term
land that is privately owned subject to market pressure
some commons easier to control than others (land, lakes, rangeland, deserts, and forests are geographically defined & easier to control than air or open oceans that do not belong to any one group
incorporating discount rates into the valuation of resources would be an incentive for investors t bear a short-term cost for a long-term gain
breaking a commons into smaller, privately owned parcels fragment the policies of governing the entire commons
Names to Know
wrote "Silent Spring", which spurred a reversal in national pesticide policy and let to a nationwide ban on DDT and other pesticides, and which inspired a grassroots environmental movement that led to the creation of the EPA.
best known for his book, "A Sand County Almanac. Influential in the development of modern environmental ethics and in wilderness conservation, emphasizing biodiversity and ecology. Developed the science of wildlife management.
helped save the Yosemite Valley, Sequoia National Park, and other wilderness areas. The Sierra Club, which he founded, is now one of the most important environmental conservation organizations in the US.
26th President of the US; used his position to pave the way for environmentalists of the future; known for setting aside land for national forests, establishing wildlife refuges, developing farmlands of the American West, and advocating protection of natural resources. He set aside 150 million acres for forest reserves, created 50 wildlife refuges, turned much of the arid land of the southwestern US into farmland, and initiated 16 major reclamation projects in the southwest.
Henry David Thoreau:
author of "Walden", which viewed unity and community as important aspects of nature, and wrote that all disturbances in these links are caused by human beings and that modern materialism would lead to the destruction of the environment needed for humans & other organisms to survive. Wrote about the need for national forest preserves and about the destruction caused by dams. His work raise environmental consciousness of many generations of readers.
Quick Review Checklist
Feeding a Growing Population
human nutritional requirements
types of agriculture
industrial agriculture (corporate farming)
low input agriculture
1st & 2nd green revolutions
Genetic Engineering & Crop Production
genetically engineered crops
efficient use of inputs
selection of site, species, and variety
types of pesticides
organic or natural
pros and cons of pesticide use
Integrated Pest Management (IPM)
methods to control fires
seed tree cutting
Hubbard Brook Experimental Forest
responsibilities of US Forest Service
Federal Rangeland Management
factors that affect resources utilization
Urban Land Development
suburban sprawl and urbanization
Federal Highway System
Canals and Channels
Case Study (Gatun Lake)
Roadless Areas & Ecosystem Impacts
Roadless Area Conservation Act (2001)
Public & Federal Lands
Federal Land Policy & Management Act (1976)
Wiilderness Act (1964)
Wild & Scenic Rivers Act (1968)
Land Conservation Options
extraction, site development, processing
trawling, drift net, long-line, purse seine, overfishing
Anadromous Fish Conservation Act 1965
Marine Mammal Protection Act 1972
Magnuson Fishery Conservation & Management Act 1976
UN Treaty on Law of the Sea 1982
Tragedy of the Commons
Bt Toxin & Round-up Ready Crops
To Be Shown During Class
Peat Bog Mummies
occurs in coal seam outcrops all around mountain
all rock and soil above coal seam removed & topsoil relocated to hollows or ravines
replaces steep topography with level surface
The Dust Bowl
The Dust Bowl,
also known as the "Dirty Thirties", was a period of severe dust storms that greatly damaged the ecology and agriculture of the US and Canadian prairies during the 1930s; severe drought and a failure to apply dryland farming methods to prevent wind erosion (the Aeolian processes) caused the phenomenon.
The Last Mountain