Lecture notes, lecture all - Conservation biology. PDF

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Conservation Biology....

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Conservation Biology Conservation Biology and Biodiversity: Conservation Biology: -integrated, multidisciplinary scientific field -developed in response to the challenge of preserving species and ecosystems -complements: applied disciplines and provides a more general theoretical approach to the protection of biodiversity -at its core: population biology (increasing/decreasing populations) taxonomy (identifying and naming species) ecology (interaction between biotic and abiotic sources) genetics (variability) -ethical principles: diversity of species and ecosystems should be preserved untimely extinction of population and species should be prevented ecological complexity should be maintained evolution should continue biodiversity has intrinsic value -origins: traced to religious and philosophical beliefs concerning the relationship between human societies and the natural world many world religions, people are seen as both physically and spiritually connected to plants and animals in the surrounding environment European Origin: -realize protection of forest was necessary -some forests should remain uncut to provide steady supply of rainfall to agriculture fields -species extinction demonstrated – wild cattle, dodo bird American Origin: -nature as a temple -experience of nature is a necessary counterweight to weakening tendencies of civilization

-intrinsic value Biodiversity: Species Diversity: -a species is defined in 3 ways: morphological, biological, and evolutionary morphological: a group of individuals that is morphologically, physiologically, or biochemically distinct from other groups in some important characteristic biological: a group of individuals that can potentially breed among themselves in the wild and that do not breed with individuals of other groups evolutionary: a group of individuals that share unique similarities of their DNA and hence their evolutionary past -all species on Earth -reflects entire range of evolution and eco adaptations of species to particular environments -speciation: process of new species formation when is a new species formed? what causes or gives rise to speciation? -phyletic evolution: gradual transformation of one species into another -adaptive radiation: process of local adaptation and subsequent speciation ex: Hawaiian honeycreeper – from one pair of birds that arrived on the Hawaiian Islands -certain groups of organisms need a minimum area to undergo speciation (ex: fish, reptiles, amphibians) Measuring Species Diversity: -Alpha Diversity: # of species in a certain area comes closest to concept of species of richness -Gamma Diversity: applies to larger geographical scales compare large areas, across diverse landscapes -Beta Diversity: gamma%alpha rate of changes of species composition along environmental or geographic gradient

Genetic Diversity: -genetic variation within species isolated and in population -maintain reproductive vitality -resistance to disease -ability to adapt -affected by the reproductive behavior of individuals within populations -population: group of individuals that mate with one another and produce offspring a species may include one or more separate populations a few to a million individuals does a single individual of a sexual species constitute a population? -an individual’s phenotype is created from its environment and its genotype Ecosystem Diversity: -different biological communities and association with chemical and physical environment -collective response of species to different environmental conditions -looking at many species within an area -Biological Community: species that occupy a particular locality and the interactions among those species -Ecosystem: a biological community, together with its associated physical and chemical environment water cycles, nutrient cycles, energy capture physical environment -Limiting Resource: requirement that restricts the size of the population for a species food, temperature, water, other resource extreme environmental conditions -Ecological Succession: gradual process of change over time in species composition, community structure, soil chemistry, and microclimatic characteristics can occur following natural and human-caused disturbance in an ecosystem -species interactions within ecosystems – composition affected by competition and predation

Predators: -dramatically reduce densities of certain prey species, eliminate some -indirectly increase the number of prey species by keeping density of other species low Carrying Capacity: -number of individuals of a particular species that the resource of an ecosystem can support -predators typically keep prey species below this number Ecologically Functional: when the population of a species is sufficiently large to have an impact on the pther species in an ecosystem Mutualistic Relationship: when 2 species benefit each other -affects community composition -symbiotic relationship: 2 species always found together in close long-term association Keystone Resources: often physical or structural occupy only a small area yet are crucial species in the ecosystem ex: salt licks, mineral pools, rotting wood Ecosystem Dynamics: -key ecosystem processes – transfer of energy, production of biomass, cycling of C, N, movement of water Ecosystem Integrity: -condition in which an ecosystem is complete in terms of species composition, structure and function -challenging to evaluate objectively and quantitatively -ex: damaged by humans, decreased water retention Healthy Ecosystem: ecosystem in which processes are functioning normally Stable Ecosystem: -ecosystems that are able to remain in the same state -resistance: ability to maintain same state even with ongoing disturbance -resilience: ability to return to an original state quickly after disturbance has occurred

World Biodiversity: Tropical Forests: -occupy 7% of land area, contain more than half of the world’s species

-great abundance of insects Coral Reefs: -colonies of tiny oral animals build the large coral reef ecosystems -marine equivalent of tropical rain forests in both species richness and complexity -occupy less than 0.1% of ocean surface area, home to 1/3 of marine fish species -high primary productivity of coral reefs -clarity of water allows sunlight to penetrate – photosynthesis occurring in algae that live mutalistically inside the coral -huge amount of niche specialization Ocean Diversity: -marine systems contain representatives from 28 of the 35 animal phyla that exist today -1/3 of these phyla exist only in marine environment -great age, enormous water volume, degree of isolation of certain seas, stability of the environment, specialization on particular sediment types and water depths Mediterranean-type Communities: -plant species -moist winters and hot/dry summers -considerable geological age, complex site characteristics, severe environmental conditions - frequency of forest fires rapid speciation and prevent the domination of just a few species Patterns of Diversity: -local variation in climate, environment, topography and geologic age are factors that affect patterns of species richness -variation in climate and environment species richness increases with: -decreasing elevation -increasing solar radiation -increasing precipitation -variation in topography, geological age and habitat size species richness increases with complex topography and great geological age Why the Tropics? -increased solar energy and abundant rainfall

12 hours day/ 12 hours night; solar energy and rainfall is very consistent -species have longer periods of stability -warm temperatures and high humidity -predictable environment and species interactions -large geographical area allows for a lot of speciation New Communities: -new communities are being discovered in extremely remote and inaccessible localities -consist of inconspicuous species bacteria, protists, small invertebrates -specialized exploration techniques -some recently discovered communities include the following: canopies of tropical trees, rarely descend to the ground microbial diversity in marine sediments at depth of 6.5 km -chemical and energetic role is very important because there is no light available -even at depth of 2.8 km in Earth’s crust interior of leaves of healthy tropical trees – rich group of fungi, thousands of undescribed species Human Microbiome Project – human body and viruses, bacteria, fungi, mites

Major Issues That Define the Discipline: To preserve biodiversity, scientists must answer 3 questions: 1.) How is the diversity of life distributed around the planet? 2.) What threats does this diversity face? 3.) What can people do to reduce or eliminate these threats and, when possible, restore biological diversity and ecosystem health? -the 3 measures of biodiversity are species, genetic, ecosystem What is a species? 1.) Morphological definition 2.) Biological definition 3.) Evolutionary definition How do you really measure species diversity? -more to species diversity than a measure of richness -there is also species evenness

relative abundance of species in an area proportion of species present in a community/area -diversity indices can incorporate both Shannon-Wiener Diversity Index: H = -∑pi logepi i=l (multiple be -1 at the end) H

=

Value of S-W diversity index

pi

=

Proportion of the ith species

=

Natural logarithm of pi.

=

Number of species in community

loge

(ln)

S

Evenness Index: H/lnS *will have to explain answer from math above (which one is more diverse/even) *-an ecosystem/area/region has the maximum diversity when all species are equally abundant *-conclusions based on diversity measures and indices have limitations comparison purposes only -within or between similar ecosystems *-no basic ecological interpretation – diversity has increased or decreased Large scale processes can help us understand the areas of biodiversity hotspots? Geological Process: -natural processes that shape the physical make up of Earth -most notably Continental Drift Theory (consistent temperatures close to the equator) and Plate Tectonics Climate: -ice/glacial retreat -plant and animal dispersal Natural Disasters: -erosion -weathering -volcanic eruptions -asteroids -meteorites

Evolution and Natural Selection: -new habitats/niches -numbers game -strongest survive -genetic diversity

Ecological Economics: Ecological and Environmental Economics: -conservation biologists strive to ensure that all costs and benefits of economic behavior are understood and taken into account when decisions are made that will affect biodiversity -unfortunately, natural resources have been undervalued environmental damage has been ignored depletion of current stocks and future values -underlying costs of environmental damage are economic in nature, solution must incorporate economic principles Market Failure: when resources are misallocated, which allows a few individuals or businesses to benefit at the expense of the larger society society can become less prosperous Negative or Positive Externality: costs or benefits that individuals not directly involved in a free exchange Open-Access Resources: water, air, soil, etc. most important and frequently overlooked negative externally is environmental damage to openaccess resources collectively owed by society or by no one essentially free The Tragedy of the Commons: -with no regulation on open-access resources, people/industry/government use and damage resources without paying more than minimal cost -market failure occurs -values of open-access resource is gradually lost to all of society -ex: by-product of manufacturing – sewage is dumped into waterways

Common Property: -resources owned by society, regulated for common benefit -market failure can occur here due to lack of enforcement of regulations Environmental Economics: sub-discipline of economics places valuation on components of the environment Ecological Economics: more closely associated with conservation biology transdiscipline aimed at developing a sustainable world Evaluating Development Projects: -conservation movement has been strengthened by assigning monetary values to species, communities, ecosystems Environmental and Economic Impact Assessments: -consider present and future effects of the projects on the environment and the economy -used to assess large development projects Cost-Benefit Analysis: -compares values gained against the costs of the project or resource use -Theoretical: if benefits outweigh costs, project goes ahead -Practical: difficult to calculate, change over time and can be difficult to measure -Precautionary Principle: may be better not to approve a project that has risk associated with it and to err on the side of doing no harm to the environment Perverse Subsidies: -many activities today seem profitable, but they are not -government subsidized industries, tax breaks, direct payments or price supports, cheap fossil fuels, free water, road networks Discount Rates: -addressed when conservation biologists and economists evaluate development projects -commonly used by economists -calculate the present value of natural resources that will be harvested or used at some point in the future -used to assign a lower current value to resources/materials that will be used in the future -higher discount rates = lower current values

National Production: -countries may be on a verge of an economic collapse when it appears like they are making economic gains -hidden costs associated with superficial economic gains ex: oil spill – costs of cleaning up, long term damage to natural environment Gross Domestic Product: -measures economic activity in a country without accounting for all the costs of non-sustainable activities causes GDP to increase, even though activities may be destructive long term -attempts made to incorporate loss of natural resources in calculation of GDP Green Accounting: -costs of depleting and damaging resources are included as part of internal cost of doing business ISEW: (Index of Sustainable Economic Welfare) -updated version is called GPI = Genuine Progress Indicator -system accounts for natural resource depletion, pollution, unequal income distribution in measures of national production GPI: -includes loss of farmlands, loss of wetlands, impact of acid rain, number of people living in poverty, effects of pollution on human health -based on this, world economy reached peak in 1978 -align with Conservation Biologists: modern economists are achieving their growth only through nonsustainable consumption of natural resources and environmental degradation EPI: (Environmental Performance Index) -used in 20 environmental indicators to rank countries according to: health of, and threats to, their ecosystems vulnerability of their human population to adverse environment ability of their society to protect environment participation in global environmental protection efforts -in general, developing nations with low GDP have low EPI -higher income countries have higher EPI Economic Value To Biodiversity: -how to assign a values to species, ecosystems, genetic variability? -frameworks have been developed for 3 levels:

1.) The marketplace (or harvest) value of resources 2.) The value provided by unharvested resources in their natural state 3.) The future value of resources -ex: Southeast Asian wild gaur – wild relative of domestic cattle value assigned based on: 1.) Meat currently harvested from its wild populations 2.) Animal’s value in the wild for nature tourism 3.) Future potential in domestic cattle breeding programs -even though there is no universally accepted framework for assigning values to biodiversity, variety of approaches have been proposed: *know chart > Direct Use Values: -calculated by observing activities of representative groups of people, monitoring collection points for natural products and examining import and export statistics Consumptive Use Value: -do not appear in GDP -if not accessible, qualify of lives (standard of living) affect may diminish -assigned to a product by considering how much people would pay if they had to buy an equivalent product when local source is no longer available -meat, fish, medicine, etc. Product Use Value: -resources that are sold in national international markets get this type of value assigned -typically valued at the price paid at the fist point of sale – costs incurred up to that point -other way is to assign value at final retail price of products *will have to evaluate a developmental project

Indirect Use Value and Ethical Issues: Ecosystem Services: -component of indirect use value

-calculated at regional and global levels -could exceed value of world’s economy -human societies are dependent on natural ecosystems -societies would not persist if ecosystem services were permanently degraded or destroyed Ecosystem Productivity and Carbon Sequestration: -photosynthetic capacity of plants and algae food, base of food chains -if lost, destroy system’s ability to make use of solar energy, loss of biodiversity and associated production of plant biomass, loss of animals, loss of natural resources -coastal estuaries -active research into how loss of species from biological communities affects ecosystem processes -environmental economists are recognizing value in intact and restored forests in retaining carbon and absorbing atmospheric CO2 Water and Soil Protection: -biological communities protect watersheds maintain water quality buffer ecosystems against flood, drought -plant foliage: intercept rain, reduce impact on soil Water Treatment and Water Retention: -aquatic ecosystems are capable of breaking down and immobilizing toxic pollutants that have been released into the environment by human activities -fungi and bacteria -when ecosystems cannot carry out this function, expensive pollution treatment facilities must be installed and operated -processing, storing, recycling large amounts of nutrients Climate Regulation: -plant communities

-local shade evaporate water cooling effect reduces need for fans, etc. -regional – capture rain, transpire, fall as rain again Species Relationships: -a decline in one species, can have an impact on harvestable species -ex: game/fish depend on insects and plants -ex: predatory insects, birds and bats feed on pest insect species which can result in higher crop yields -pollination -fungi and bacteria – break down dead plant and animal matter, used as energy source during this process, mineral nutrients are released into the soil – used by plants mutualistic relationship – plants provide photosynthetic product for microorganism growth Environmental Monitors: -species that are sensitive to chemical toxins serve as warning indicators for health of environment -can substitute for expensive detection equipment Amenity Value: -recreational services -monetary value of activities -ecotourism: spending money wholly or in part to experience unusual biological communities, view as common species Educational and Scientific Value: -increase human knowledge, enhance education, enrich human experience Option Value: -long-term view -benefit to human society at some point in the future -potential economic or human health value of natural resources motivates people and countries to protect biodiversity -biological control agents: control of exotic and/or invasive species -who owns the commercial development rights to the world’s biodiversity

Existence Value: amount people are willing to pay to prevent species from going extinct, habitats from being destroyed, genetic variation from being lost -people care -bequest value: how much people are willing to pay to protect something of values for their own children and future generations Is Economic Value Enough? -attention is placed on goods and services provided by biodiversity, enables scientists to account for environmental impacts that were not previously considered -assists in determining the development of large projects -will placing a numer...