BESC 201 11 6 2013 Exam 3 Study Guide Lectures 21 28 Chapter 7 Lectures 21 23 October 21 25 Our species has a 10 000 year history with agriculture and over this time methods of food production have changed substantially Many practices of intensive industrial agriculture exert substantial negative environmental impacts At the same time the increased production had boosted food supplies and helped to relieve certain pressures on land or resources What is certain is that if our planet is to support 9 billion people by mid century without further degrading the soil water pollinators and other resources and ecosystem services that support our food production we must find ways to shift to sustainable agriculture Approaches such as biological pest control organic agriculture pollinator conservation preservation of native crop diversity sustainable aquaculture and likely some degree of careful and responsible genetic modification of food may all be parts of the game plan we will need to set in motion to achieve a sustainable future Central Case Study Iowa s Farmers Practice No Till Agriculture Turning the earth by tilling plowing disking harrowing or chiseling aerates the soil and works weeds and old crop residue into the soil to nourish it Tilling also leaves the surface bare allowing wind and water to erode away precious topsoil No Till Farming Rather than plowing after each harvest farmers leave crop residues atop their fields keeping the soil covered with plant material at all times To plant the next crop they cut a thin shallow groove into the soil surface drop in seeds and cover them Conservation Tillage an approach involving limited tilling Chapter 8 Lectures 24 and 25 October 28 30 Data from scientists worldwide confirm what any naturalist who has watched the habitat change in his or her hometown already knows From amphibians to tigers biological diversity is being lost rapidly and visibly within our lifetimes This erosion of biodiversity threatens to result in a mass extinction event equivalent to those of the geologic past Habitat alteration invasive species pollution overharvesting of biotic resources and climate change are the primary causes of biodiversity loss This loss matters because human society cannot function without biodiversity s many pragmatic benefits Conservation biologists are rising to the challenge of conducting science aimed at saving endangered species protecting their habitats recovering populations and preserving and restoring natural ecosystems The innovative strategies that scientists are pursuing hold promise to slow the loss of biodiversity on Earth Central Case Study Saving the Siberian Tiger Just over 3 000 tigers survive down from 100 000 a century ago The tigers last refuge is in the forests of the remote Sikhote Alin Mountains of the Russian Far East Poachers hunt tigers for sport hides and body parts Logging road building and agriculture degraded and fragmented tiger habitat providing easy access for poachers The Hornocker Wildlife Institute now part of the Wildlife Conservation Society WCS launched the Siberian Tiger Project In November 2010 leaders of the 13 nations where tigers still survive met at a historic summit in St Petersburg Russia marking the first time that multiple heads of state had ever convened to focus on saving a single species of wild animal At this International Tiger Forum the leaders signed a declaration that set in motion a strategic multinational plan called the Global Tiger Recovery Program o Aims to double the tiger population by 2022 the nest Year of the Tiger by the Chinese zodiac Chapter 9 Lecture 26 November 1 Forests are ecologically vital and economically valuable yet we are losing forests around the world In North America forest management early emphasis on resource extraction evolved into policies on sustainable yield and multiple uses as land and resource availability declined Public forests today are managed not only for timber production but also for recreation wildlife habitat and ecosystem integrity Sustainable forest certification provides economic incentives for conservation on forested lands Meanwhile public support for the preservation of natural lands has led to the establishment of parks and protected areas in the United States and abroad As development spreads across the landscape fragmenting habitats and subdividing populations scientists trying to conserve species communities and ecosystems are thinking and working at the landscape level Central Case Study Certified Sustainable Paper in Your Textbook The trees cut to make this textbook s paper were selected for harvest based on a sustainable management plan designed to avoid depleting the forest of its mature trees or degrading the ecological functions the forest performs The paper mill at Escanaba Michigan recycles chemicals and water used in the process and it combusts discarded waste to help power the mill Independent third party inspectors from the Forest Stewardship Council FSC examine the practices being used to ensure that they meet the FSC s strict criteria for sustainable forest management and paper production The Forest Stewardship Council is an organization that officially certifies forests companies and products that meet sustainability standards Chapter 12 Lectures 27 and 28 November 4 6 Our planet s diverse aquatic systems compromise an interconnected web of ecosystems that exchange water The introduction of pollutants and the engineering of waterways therefore cause impacts that cascade through the system Our expanding population and increasing water use are straining water supplies and affecting surface waters and groundwater around the world Water pollutants threaten human health and ecosystem stability and overharvesting of marine fish populations threatens the oceans biodiversity There is plenty of reason for optimism however Improvements in water use efficiency show promise for reducing demand for water even with increasing human populations Water quality in many freshwater bodies has improved in recent decades thanks to legislative action from policymakers and the efforts of millions of concerned citizens In the oceans marine reserves give hope that we can restore ecosystems and fisheries at the same time Central Case Study Starving the Louisiana Coast of Sediment The state of Louisiana is shrinking Wetlands are disappearing beneath the waters of the Gulf of Mexico Louisiana has lost nearly 4 900 km of coastal wetlands an