Lecture 2: Values in Conservation Biology PDF

Lecture 2 ↑ Values in Conservation Biology Why should we care about preserving biodiversity...the genetic...the organism...the ecosystem LINK!!  Climate and the Biogeochemical Cycles The creation of the air we breathe and the supply and distribution of water we drink...

Lecture 2 ↑ Values in Conservation Biology Why should we care about preserving biodiversity...the genetic...the organism...the ecosystem LINK!!  Climate and the Biogeochemical Cycles The creation of the air we breathe and the supply and distribution of water we drink. Photosynethesis generates oxygen and provides food for ALL living things How much value, price tag, you would put on this service!!!? Through global geochemical cycles, the planet’s climate, ecosystems, and creatures are tightly linked. Changes in one component can have drastic effects on another, as exemplified by the effects of deforestation on climatic change, especially the hydrologic cycle Nitrogen and phosphorous cycles are important for building living organisms, in addition to other things Disruption of those cycles will affect living systems and ecosystems viability  Soils and Erosion ! Forest and plant cover protects soil from erosion-loss of top fertile soil Every year about 75 billion tons of soil are thought to be eroded from terrestrial ecosystems, at rates 13–40 times faster than the average rate of soil formation In the second half of the 20th century about a third of the world’s arable land was lost to erosion. This means losing vital harvests and income, not to mention losing lives to malnutrition and starvation Intensive cultivation, by lowering soil’s organic matter content, can reduce this capacity, leading to floods, erosion, pollution, and further loss of organic matter Soil is also critical in filtering and purifying water by removing contaminants, bacteria, and other impurities  Soils harbor an astounding diversity of microorganisms, including thousands of species of protozoa, antibiotic-producing bacteria and fungi (producing penicillin), as well as myriad invertebrates, worms and algae These organisms play fundamental roles in decomposing dead matter, neutralizing deadly pathogens, and recycling waste into valuable nutrients Not to mention nitrogen-fixing bacteria, without which there will be no life!  Biodiversity and Ecosystem Function Increased biodiversity improves ecosystem functioning in plant communities Different plant species capture different resources, leading to greater efficiency and higher productivity When humans alter ecosystems, large mammals are typically the first species to disappear The loss of carnivores has induced trophic cascades: in the absence of top predators, herbivores can multiply and deplete the plants, which in turn drives down the density and the diversity of other species The more complex an ecosystem is, the more biodiversity will increase ecosystem function More biodiverse ecosystems are also likely to be more stable and more efficient  Mobile Links Pollinators and seed dispersing animals help spread individuals to new areas, thus expanding and increasing genetic diversity Up to 98% of tropical rainforest trees are pollinated by animals More than 1200 vertebrate and about 289 000 invertebrate species are involved in pollinating over 90% of flowering plant species (angiosperms) and 95% of food crops. Bees, which pollinate about two thirds of the world’s flowering plant species and three quarters of food crops Consumers help stabilize population densities of prey Scavengers speed the process of decomposition Predators can act like biological control agents of pests Birds can be important fertilizing agents of soils through their droppings Some like the beaver, who make dams amidst a river, create new ecosystems allowing different biodiversity to exist in an already existent ecosystem  Nature’s Cures Nearly half of all human pharmaceuticals now in use were originally derived from natural sources. Most famous example is aspirin, which evolved from a compound found in the bark and leaves of the willow tree and was later marketed by Bayer starting in 1899. Some 50 years later, scientists identified anticancer compounds in the rosy periwinkle (right), which pharmaceutical heavyweight Eli Lilly subsequently produced for the treatment of leukemia and Hodgkin's disease. Other well-known examples include the cancer-fighting Taxol, isolated from the Pacific yew tree, and Aggrastat, an anticoagulant based on the venom of the saw- scaled viper from Africa.  Summary Ecosystem services are the set of ecosystem functions that are useful to humans. These services make the planet inhabitable by supplying and purifying the air we breathe and the water we drink. Disruptions of biogeochemical cycles can lead to floods, droughts, climate change, pollution, acid rain, and many other environmental problems. Soils provide critical ecosystem services, especially for sustaining ecosystems and growing food crops, but soil erosion and degradation are serious problems worldwide. Higher biodiversity usually increases ecosystem efficiency and productivity, stabilizes overall ecosystem functioning, and makes ecosystems more resistant to perturbations.  Mobile link animal species provide critical ecosystem functions and increase ecosystem resilience by connecting habitats and ecosystems through their movements. Their services include pollination, seed dispersal, nutrient deposition, pest control, and scavenging. Thousands of species that are the components of ecosystems harbor unique chemicals and pharmaceuticals that can save people’s lives, but traditional knowledge of medicinal plants is disappearing and many potentially valuable species are threatened with extinction ***Just pay attention to the service and provider/trophic level Reasons for Biodiversity Instrumental - Material Anthropocentric Value - Non-material Intrinsic Biocentric  Gifford Pinchot (1865 – 1946) First Chief of the U.S. Forest Service (1905 – 1910) Coined “conservation ethic” a nthropo centric Resource Conservation Ethic Utilitarian, anthropocentric “natural resource” philosophy; “the greatest good of the greatest number for the longest time”  Material… Goods – food, fuel, fiber, medicine, etc. Services – pollination, nutrient cycling, nitrogen fixation, decomposition, etc. ↓ Information – genetic engineering, ~ applied biology, basic science, etc.  John Muir (1838 – 1914) Founded Sierra Club (1892) & Romantic-Transcendental Conservation Ethic 3 “Nature has uses other than human economic gain;” biophilia  Instrumental Value - Non-material Psycho-spiritual – (e.g., biophilia, as contrasted with biophobia) aesthetic beauty, religious awe, scientific knowledge, etc.  Islamic Worldview The Koran teaches that Allah (God) calls for man’s stewardship to provide a just distribution of natural resources across generations  Monetizing Instrumental Value of Nature Costanza et al. (1997, Nature) provide this estimate for the value of these ecosystem goods & services: ~ $33,000,000,000,000 / yr […and the gross world product (the sum of all nations’ gross national products) is ~ $18,000,000,000,000 / yr] Why should we care? Ehrlich & Wilson (1991, Science) provide their three-point answer… 1. Ethical & esthetic reasons (instrumental & intrinsic value) E.g., would you rather live in a world with or without grizzly bears, orchids, and dragonflies? E.g., do we humans have the right to drive species to extinction? E.g., do we humans have the right to leave the world in worse shape for our children and grandchildren than it was in when we were born? 2. Potential for new discoveries (instrumental value) …in food science, the pharmaceutical industry, and manufacturing owing to the vast riches of genetic biodiversity 3. The economic value of ecosystem services (instrumental value)