Conservation FINAL

What are some human activities that threaten biodiversity?

Agriculture, fisheries, urbanization, industry, and international trade.

What are some consequences of biodiversity loss?

Extinction of species, degradation of ecosystems, and erosion of genetic diversity.

Historically, what has been the primary cause of ecosystem change?

Agricultural expansion

What percentage of the land area of Europe and South Asia is under cultivation?

Over 70%

What is the impact of intense forms of agriculture on biodiversity?

They disrupt most ecosystem processes and result in losses at every level of biodiversity.

What percentage of the Earth's terrestrial surface is occupied by grazing?

it occupies 26% of the earth’s terrestrial surface

In the United States, what percentage of grazing land is not suitable for crops?

85%

What are the negative effects of overgrazing?

Deforestation and degradation of rangeland.

What percentage of the planet's arable land is occupied by livestock feed crops?

One-third

Why is feeding livestock grains considered an inefficient use of crops?

• It takes about 100 calories of grain to produce 3 calories worth of beef, which is an ecologically inefficient use of calories.

• livestock that are fed grains have a far larger ecological foot print than those pasture raised.

What are the ecological footprints urban areas?

Much greater than their physical size due to resource consumption.

Approximately what fraction of the world’s population lives in cities?

About 1/2

What is one major source of environmental degradation caused by urban populations?

Waste generation through pollution and conversion of natural habitats to landfills.

How do urban environments impact water runoff?

They increase runoff due to impervious surfaces, leading to flooding and pollution (oil &gas from cars, fertilizers & pesticides, or chemical runoff from factories).

What percentage of the world’s population lives within 100 km of a coast?

40%

What percentage of ecosystems adjacent to the oceans have been highly modified?

20% of coastal ecosystems have been altered due to human activity, affecting biodiversity and ecosystem services.

What impacts do urban environments have on freshwater systems?

Draining and filling wetlands, water use from aquifers, lakes, and streams, and pollution.

What percentage of the area of the United States is covered by roads and their adjacent impact zones?

An estimated 20%

What are some of the ways that roads can harm the environment?

They can penetrate remote areas, spread exotic species, and alter aquatic and terrestrial ecosystems.

How do roads impact adjacent terrestrial ecosystems?

They can spread dust, sediment, salt, heavy metals, and hydrocarbons, create a sunny, windy & warm microclimate, block water infiltration, and disturb wildlife with traffic noise.

What is the wildland-urban interface?

The zone of transition between unoccupied land and human development.

How much water is the world using per year?

9,087 billion m3 (China, India, U.S., and Brazil)

Which country has the world's highest water consumption per person per year?

U.S.

What are some examples of aquatic ecosystems affected by over-extraction of water?

Rio Grande, The Everglades, Ogallala Aquifer, and Cape Town, South Africa.

What is a negative effect of logging?

it can contribute to deforestation and forest degradation

What ecosystem are often affected by logging?

tropical forests account for ~25% of the global industrial wood production

What are some of the impacts of mining and quarrying?

Devastating impacts on native habitat and can create soil disturbances (mine tailings, mountaintop removal, and oil sands)

How negative is the impact of fisheries compared to mining?

Many fisheries practices are closer to mining in their impacts on marine systems, if current fishing rates continue, all of the world’s fisheries will collapse by 2050

what are some impacts of fishing gear?

• trawling

• explosives and cyanide

• bycatch

What kind of direct effects does international trade have?

transport and infrastructure

• increase from <4 B to ~12 B

• cargo ships are highly polluting (SOX and NOX)

• port development damages seashore ecosystems

• airplane emissions are a significant contributor to climate change and create polluting particles and noise pollution

• airports have a large physical footprint

Pests, pathogens, and invasive species

• transport of contaminated goods, plants, and animals (spotted lanternfly)

• hitchhiking species on planes, ships, and vehicles

Trade of threatened species

• illegal animal trade

What are some indirect effects of international trade?

high-income countries have sourced labor-intensive goods from cheaper sources, resulting in East Asia becoming the ‘factory of the planet’

What did humans wipe out by mid-1900

Atlantic cod, herring, and California sardines were harvested to the brink of extinction

What is a pollutant?

A substance introduced into the environment that has undesired effects, potentially harming wildlife, humans, and entire ecosystems due to toxicity or altered chemical balance.

What is point source pollution?

Pollution discharged from a single identifiable source, such as a pipe, ditch, ship, or smokestack.

What is nonpoint source pollution?

Pollution originating from broad areas, such as sediments, pesticides, and fertilizers carried by runoff from agricultural fields, lawns, and streets; considered the leading threat to endangered freshwater species in the US.

What are acute effects of pollution?

Direct mortality or impairment of reproduction; severe and visible impacts (e.g., oil spills).

What are chronic effects of pollution?

Persistent exposure to sublethal levels of toxins, leading to altered sexual, neurological, and behavioral development, impaired health, growth, or reproduction, compromised immune systems, and chemical transfer from parent to offspring.

What are major sources of air pollution?

Transportation, fuel combustion from power plants, space heating of buildings, industrial processes, solid waste disposal, and burning of forests and agricultural lands.

What is acid deposition?

Primarily nitrogen oxides and sulfur dioxides from power plants burning fossil fuels that transform into nitric and sulfuric acids in the atmosphere, settling as acid rain, snow, or dry particulates.

What are the effects of acid deposition on animals?

Low pH levels can kill adult fish, inhibit fish egg hatching, cause thinner egg shells in birds, and damage frogs, toads, and reptiles in aquatic ecosystems; aluminum leached from soils causes problems for aquatic life.

What are the effects of acid deposition on plants?

Lowers soil pH, changes soil chemistry, leaches minerals and nutrients, and directly damages plants when acid rain falls on leaves.

What is the primary source of mercury (Hg) contamination in the US?

Coal-fired power plants release Hg into the atmosphere as a byproduct.

What is methylmercury?

A highly toxic form of Hg that accumulates in animal tissues, acting as a potent neurotoxin impacting the central nervous system.

Why is methylmercury dangerous?

It increases in concentration with each step up the food chain and poses serious health risks to people and wildlife who consume contaminated fish or other species.

Define 'habitat'.

The physical and biological environment used by an individual, population, or species.

What occurs during habitat degradation?

Habitat quality is diminished (ex: contaminants reduce the ability of a species to reproduce in an area)

What occurs during habitat loss?

Habitat quality is so low that the environment is no longer usable by a given species (ex: filling a wetland and building a shopping plaza)

Define 'ecosystem'.

A group of interacting organisms and the physical environment they inhabit at a given point in time.

What is ecosystem loss?

Changes to an ecosystem are so profound that the ecosystem is converted to another type (ex: deforestation and draining wetlands)

What is ecosystem degradation?

Alterations to an ecosystem degrade or destroy habitat for many of the species that constitute the ecosystem (ex: warm water from a power plant increases the temperature of a river, causing many temp-sensitive species to disappear)

What amount of Tropical Rainforest is remaining?

< 9 million km2 remains of the roughly 16 million km2 that originally existed, with loss per year ranging from 60,000 - 130,000 km2

What are some characteristics of Tropical rainforests?

They are being destroyed rapidly and are the most biologically diverse of all terrestrial biomes.

Why have Tropical Dry forests suffered worse losses than rainforests?

They are easier to clear and burn than rainforests. They serve as spawning and rearing areas for economically important fish and shrimp species.

Why have temperate forests and woodlands suffered worse destruction than tropical forests?

Long history of human settlement in many temperate regions. Old growth broadleaf forests have nearly disappeared in eastern US and Europe.

Why have coniferous forests been less severely reduced than broadleaf and mixed forests?

Forests are converted from old-growth to timber-production forests, which have a much-simplified stand structure and species composition.

How have grasslands and desert areas suffered to a lesser extent than forests?

About 1/3 of the world’s deserts have been converted to other land uses. 10–20% of all grasslands have been permanently destroyed for agriculture.

Besides logging, what other activities take a toll on Boreal Forests?

Mining, oil and gas extraction, and hydroelectric development have also taken considerable tolls on the boreal forest.

How have Wetlands been affected by intense habitat destruction?

In the US, over half of all wetlands have been destroyed in the last two centuries. 60–70% of European wetlands have been destroyed.

How does water diversion and damming affect rivers and streams?

• they degrade or destory rivers and streams

• it contributes to endangerment for over 90% of federally-listed fish and mussels in the US.

• only 2% of rivers run unimpeded

How does agriculture and land clearing impact nearby water bodies?

• sedimentation ruins stream bottoms for macroinvertebrates and spawning fish

• shift streams from fast flowing, deep water to still, shallow waters that favor a different assemblage of species

What effects are humans making to Marine Systems?

• die‐offs of fish and corals, blooms of jellyfish and algae, and “dead zones” of oxygen‐depleted waters

• coastal development has removed much of the worlds mangroves, sea grass beds, and salt marshes

• climate change is leading to sea-level and ocean temperature rise, as well as ocean acidification

• invasive species introduction

How do human activities compound to make synergisms among stressors?

Each activity by itself may have no effect but synergisms among stressors can amplify impacts (e.g., excess nutrient input combined with overfishing of herbivorous fish on coral reefs can lead to algal proliferation and loss of coral).

Define Deforestation.

Permanent removal of trees and conversion to another land-use (e.g., agriculture, grazing, human structures).

How can deforestation affect broader climate and conditions?

• Evaporation and transpiration loops will be interrupted, creating hot, dry conditions that can exacerbate droughts and alter precipitation patterns.

• Release stored carbon

• soil erosion can contaminate aquatic ecosystems

How has deforestation affected Madagascar?

• <25% of the island remains in forests and woodlands. Virtually all ecosystems have been highly degraded.

• elephant birds, giant lemurs, and giant tortoises disappeared after humans inhabited much of the island

• loss of forests and resulting siltation have affected freshwater and coastal ecosystems

What is meant by Desertification?

The process in which arid and semi-arid areas (e.g., grasslands and woodlands) become increasingly arid, leading to loss of vegetation and wildlife

How does Overgrazing of livestock contribute to Desertification?

Too many cattle, sheep, goats, and other livestock consume and trample plants. Animal hooves break and compact the soil, increasing erosion.

Why should arid environments be given careful consideration, even though they support fewer species than humid environments?

Arid environments support fewer species than humid environments but still have biodiversity value. Thousands of species are found in deserts and many are highly endangered.

How can changing their hydrology degrade Freshwater Ecosystems?

Freshwater ecosystems, marine ecosystems, and wetlands can be degraded or destroyed by changing their hydrology.

How do draining techniques affect the water table of a wet ecosystem?

Digging ditches can be used to drain large areas relatively easily. Lowering the water table of a wet ecosystem by moving the water somewhere else.

How does Filling techniques affect the surface of the water table?

Adding material to a wet depression until the surface of the water table is well below ground. Routinely used to create house lots, airports, parking lots, and other high-priced land.

What is dredging and what goal does it attempt to achieve?

Digging up the bottom of a water body and depositing the material elsewhere. Maintaining a shipping channel.

What is channelizing and what problems can it create?

Making rivers and streams straighter, wider, and deeper. Converts a complex of natural riverine communities to a barren canal.

• replaces riparian vegetation with banks of stone or concrete

What occurs upstream when damming rivers and streams?

A flowing-water (lotic) ecosystem is converted to a standing-water (lentic) ecosystem. Wetland and upland ecosystems will also be flooded and thus become part of a reservoir.

What occurs downstream when damming rivers and streams?

Floodplain ecosystems are likely to be replaced by upland ecosystems if the dam minimizes or eliminates seasonal floods. Unnatural flow rates.

What is the case study example for Altered Hydrological Regimes?

Aral Sea - once the 4th largest lake in the world is now nearly gone (10% of its original size)

• as the lake dried up, fisheries and communities that depended on them collapsed

What are the impacts of altered fire regimes?

• natural grasslands and shrublands that are adpated to low-intesity fires are overrun by fire-intolerant species

• when low-intensity fires are suppressed, fuel can accumulate and create high-intensity fires

How did the US Forest Service help cause altered fire regimes?

US Forest Service started the Smokey Bear campaign, which portrayed all fire as destructive.

How is the Kirtland's Warbler an example of how fire suppression can affect endangered species?

Fire suppression led to a shortage of young jack pine stands in Michigan, the sole habitat of the endangered Kirtland's warbler.

What human activities often cause soil erosion at a higher rate?

Agriculture, overgrazing by livestock, timber harvesting, and road and building construction collectively erode soil at a greater rate than all natural processes combined.

How much faster are we losing topsoil than it can be replenished

Soil is being lost at 10-40 times the rate at which it can be naturally replenished (~500 years to create 25 mm of topsoil).

• 10 times faster in the U.S.

• 30-40 times faster in China and India

What is the result of Soil Erosion?

Remaining soil is often stripped of carbon and nutrients. Soil erosion produces sediments that can blanket other ecosystems (Obscures vision of aquatic animals, prevents light from reaching aquatic vegetation, clogs fish gills, etc.)

What is the Round Island example of soil erosion and degradation?

• rabbits and goats were introduced to a previously deep soil covered, hardwood forest island and degraded almost all of the vegetation

• caused giant tortoise and boa to go extinct

• goats and rabbits were removed in the 70s/80s nad erosion was brought under control

Define Fragmentation.

The process by which a continuous habitat is broken up into distinct pieces that are isolated from one another in a matrix of lands dominated by human activities.

What 3 processes take place during Fragmentation?

A reduction in the total amount of the original vegetation (i.e., habitat loss), subdivision of the remaining vegetation into isolated fragments, remnants, or patches (i.e., habitat fragmentation) and introduction of new forms of land-use to replace vegetation that is lost.

How does fragment size affect Fragmentation?

Small fragments have fewer species than large fragments.

How does large areas affect fragment size?

Large areas will have a greater variety of environments than small areas and each of these will provide niches for some additional species.

How does fragmentation affect home-range species?

• Species with large home ranges (e.g., wolves) are unlikely to be found in a small patch of habitat

• even species with a limited home range may avoid small habitat patches

• some species require habitat patches large enough to support other members of their species (e.g., colonial species like puffins)

What is the fragmentation effect concerning Isolation?

More isolated fragments have fewer species than less isolated fragments.

• greater the isolation, the more likely the individual will not survive the migrations to or from the fragment

How does Isolation depend on types of land-use between fragments?

• For terrestrial species, a large expanse of cropland is a barrier nearly as effective as a stretch of water.

• Human infrastructure may be a more effective barrier to movement.

How can Roads be a barrier for small flightless animals?

Roads with curbs or lane dividers are an absolute barrier to small, flightless animals such as amphibians, small reptiles, and various invertebrates.

How are Dams a barrier for Fragmentation?

Many animals move up and down rivers during their life cycle to forage or breed. Fish are the best-known victims of dams, especially anadromous fish such as salmon

How does Amount of Edge affect Fragmentation?

• as size of fragment decreases, its perimeter to area ratio increases

• a circle is the best shape for a fragment because it has the shortest perimeter relative to its area

How can edges be beneficial in fragmentation?

Edges benefit species that need both types of habitat or prefer the transitional habitats the edges provide

Explain the Edge effect due to fragmentation

The physical environment near an edge is different. Temperatures may exceed thermal tolerance of animals and affect activity times.

How does edge effect apply to impacted zones?

Width of the “impact zones” vary from tens of meters in the case of microclimate issues to kms in the case of poachers invading a protected reserve.

What is the Equilibrium theory of biogeography?

A theory that explains the number of species on an island based on the balance between immigration and extinction rates as influenced by island size and distance from the mainland.

• only predicts species presence not abundance

How is Equilibrium maintained?

The number of species on an island represents a balance between colonization and extinction.

What determines colonization and extinction rates?

The fewer species on the island, the higher the colonization rate. The more species on the island, the higher the extinction rate.

What is the Metapopulation effect?

A group of spatially separated populations of the same species that are connected by immigration and emigration (i.e., a “population of populations”).