Gonzaga Debate Institute 2011 Gemini Landsats Neg
AT: Bio-D – No Solve – Freshwater
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- AT: Bio-D – No Solve – Conservation Fails
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AT: Bio-D – No Solve – FreshwaterFreshwater bio-d is terminally dead – too many challenges Dudgeon et al 6 (David, Dept. of Energy and Biodiversity, U Hong Kong, Biol. Rev. 81, pp. 163–182, http://bscw.ihe.nl/pub/bscw.cgi/d2840228/Dudgeon-et-al%202005%20Freshwater%20Biodiversity.pdf, accessed 7-6-11, JMB) A significant challenge to freshwater biodiversity conservation results from the complexity imposed on freshwaters by catchment divides and saltwater barriers. As a result, low gene flow and local radiation lead – in the absence of human disturbance – to considerable inter drainage variation in biodiversity and high levels of endemism (Table 3). This is especially notable among assemblages that evolved in isolated lakes on islands or mountains and inland plateaux such as the karstic regions of Burma and southwest China (Kottelat & Whitten, 1996). These and similar tropical uplands are poorly represented in existing protected-area networks (Rodrigues et al., 2004). Ancient lakes such as Lake Baikal in Siberia and those in the East African Rift Valley support well-known species flocks of endemic crustaceans and fishes, but there are important radiations of cichlids, cyprinids, catfishes and other fishes, as well as frogs, crustaceans and molluscs, elsewhere in Africa (Table 3) and the world. For example, species flocks occur among Cyprinidae in the Philippines, Telmatherinidae on Sulawesi, and Balitoridae in China (Kornfield & Carpenter, 1984; Kottelat & Chu, 1988 ; Kottelat & Whitten, 1996). Virtually all of these radiations are severely endangered, as the examples from Africa illustrate (Table 3). At smaller geographic scales there is substantial species turnover (i.e. b-diversity) among drainage basins and water bodies, and many freshwater species have restricted ranges (e.g. Sheldon, 1988 ; Pusey & Kennard, 1996 ; Strayer et al., 2004). These attributes combine with endemism to produce a lack of ‘substitutability’ among freshwater habitat units. This means that protection of one or a few water bodies cannot preserve all freshwater biodiversity within a region, or even a significant proportion of it. In addition to conflicts arising from the multiple use of water, conservation of freshwater biodiversity is complicated by their landscape position as ‘receivers ’ and the problems posed by high levels of endemism – and thus non-substitutability. Other features intrinsic to freshwater environments, especially rivers, also make them vulnerable to human impacts. Rivers are open, directional systems, and elements of their biota range widely using different parts of the habitat at various times during their lives. Fishes and other animals (from shrimps to river dolphins) use different habitats at different times, and longitudinal migrations may be an obligatory component of life histories especially if – as in many species – migration is associated with breeding (Welcomme, 1979). Longitudinal migrations may occur within the river, or from river to sea or lake and back, or from sea or lake to river and back. Such movements put animals at risk from stresses in various parts of their habitat at different times ; long-lived species with low reproductive rates are likely to be the most vulnerable (Carolsfeld et al., 2004). Dams in tropical regions are generally constructed without appropriate fishways or fish passes, or based upon designs that are suitable only for salmonids, and thus they obstruct fish migrations (Roberts, 2001). A dam on the lower course of a river prevents migratory fishes with an obligate marine phase in their life cycle from moving to and from the sea, creating the potential for activities in downstream reaches to impact upstream portions of the river by way of, for example, the nutrient transmission that occurs during spawning migrations of salmon (e.g. Naiman et al., 2002 a; see also Pringle, 2001). Lateral migrations, between inundated floodplains or swamp forest and the main river channel, represent another axis of connectivity important for feeding and breeding in many fishes and other animals (Welcomme, 1979; Ward et al., 2002; Carolsfeld et al., 2004 ; Arthington et al., 2005) that is dramatically altered by human activities. AT: Bio-D – No Solve – Conservation FailsConservationism fails – external factors Ehrlich 88 (Paul R., Prof of Biological Sciences at Stanford, Chapter 2 of Biodiversity, by Edward O. Wilson, Frances M. Peter, National Academy of Sciences, google books, JMB) Arresting the loss of diversity will be extremely difficult. The traditional "just set aside a preserve" approach is almost certain to be inadequate because of factors such as runaway human population growth, acid rains, and climate change induced by human beings. A quasi-religious transformation leading to the appreciation of diversity for its own sake, apart from the obvious direct benefits to humanity, may be required to save other organisms and ourselves. AT: Bio-D – No Solve – Resource UseBio-d loss inevitable – humans use too much of the Earth’s resources Ehrlich 88 (Paul R., Prof of Biological Sciences at Stanford, Chapter 2 of Biodiversity, by Edward O. Wilson, Frances M. Peter, National Academy of Sciences, google books, JMB) This utter dependence of organisms on appropriate environments {Ehrlich, 1986) is what makes ecologists so certain that today's trends of habitat destruction and modification—especially in the high-diversity tropical forest (where at least one-half of all species are believed to dwell)—are an infallible recipe for biological impoverishment. Those politicians and social scientists who have questioned the extent of current extinctions are simply displaying their deep ignorance of ecology; habitat modification and destruction and the extinction of populations and species go hand in hand. The extent to which humanity has already wreaked havoc on Earth's environments is shown indirectly by a recent study of human appropriation of the products of photosynthesis (Vitousek ct al., 1986). The food resource of the animals in all major ecosystems is the energy that green plants bind into organic molecules in the process of photosynthesis, minus the energy those plants use for their own life processes—growth, maintenance, and reproduction. In the jargon of ecologists, that quantity is known as the net primary production (NPP). Globally, this amounts to a production of about 225 billion metric tons of organic matter annually, nearly 60% of it on land. Humanity is now using directly (e.g., by eating, feeding to livestock, using lumber and firewood) more than 3% of global NPP, and about 4% of that on land. This is a minimum estimate of human impact on terrestrial systems. Since Homo sapiens is one of (conservatively) 5 million species, this may seem an excessive share of the food resource. But considering that human beings are perhaps a million times the weight of the average animal (since the overwhelming majority of animals are small insects and mites) and need on the order of a million times the energy per individual, this share might not be too unreasonable. Yet human beings can be thought of as co-opting NPP not only by direct use but also by indirect use. Thus if we chalk up to the human account not only the NPP directly consumed, but such other categories as the amount of biomass consumed in fires used to clear land, the parts of crop plants not consumed, the NPP of pastureland (converted from natural habitat) not consumed by livestock, and so on, the human share of terrestrial NPP climbs to a staggering 30%. And if we add to that the NPP foregone when people convert more productive natural systems to less productive ones (such as forest to farm or pasture, grassland to desert, marsh to parking lot), the total potential NPP on land is reduced by 13%, and the human share of the unreduced potential NPP reaches almost 40%. There is no way that the co-option by one species of almost two-fifths of Earth's annual terrestrial food production could be considered reasonable, in the sense of maintaining the stability of life on this planet. These estimates alone both explain the basic causes and consequences of habitat destruction and alteration, and give reason for great concern about future trends. Most demographers project that Homo sapiens will double its population within the next century or so. This implies a belief that our species can safely commandeer upwards of 80% of terrestrial NPP, a preposterous notion to ecologists who already see the deadly impacts of today's level of human activities. Optimists who suppose that the human population can double its size again need to contemplate where the basic food resource will be obtained. Bio-d loss inevitable – resource consumption Maurer 96 (Brian A., Associate Professor. Michigan State University, Department of Fisheries & Wildlife, Department of Geography, Biodiversity Letters, Vol. 3, No. 1, Jan, p. 1-5, JSTOR, JMB) Two important points emerge from the analysis above. First, at currently measured rates of human resource consumption, it is virtually assured that eventually the human population will consume so much energy that there will be little or none left for other species. Exactly how long it will take, and what course the loss of biodiversity will take are open to question, and depend on the reliability with which current empirical models relating diversity to energy can be applied to the human consumption problem. If the power model is appropriate, then biodiversity will be lost relatively slowly until humans consume a large fraction of primary productivity, after which it should drop very rapidly with increasing human consumption. Although the exact figure of how rapidly this major low of biodiversity will occur is open to some question, the calculations presented here imply that unless human consumption changes drastically in the next century, this major loss of biodiversity is a virtual certainty. Directory: files files -> Answer True False 2 points Question 2 files -> Integer programming and game theory files -> 4 Integer Programming files -> Bpa vehicle Window Repair Scenario #1 task: Procure vehicle window relacement. 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