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4 Environmental Threats and Opportunities
Pages 185-232

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From page 185...
... Rather, it is to highlight some of the most serious environmental obstacles that might be met in plausible efforts to reach the goals outlined in Chapter l and along development paths such as those explored in Chapters 2 and 3, to take timely steps to avoid or circumvent these obstacles. This chapter begins with a brief discussion of the approaches and issues we considered in scouting the environmental hazards that societies may confront.
From page 186...
... Neither population growth, nor climate change, nor water limitations will be the same in lapan as in the Sudan. The environmental hazards that nations and communities find most threatening and the response strategies they look to will continue to be
From page 187...
... While our analysis builds on numerous national and international "stock-taking" efforts, we ultimately focus our attention on those issues that cut across sectors and that interact to simultaneously threaten human and ecosystem health, urban development, industrial advances, and sustained agricultural production. We conclude that integrative solutions those aimed at interacting challenges across many sectors will be key to successfully navigating the transition to sustainability.
From page 188...
... From their analysis, it is apparent that the availability of high-quality freshwater is a priority concern in the United States, whether the most weight is given to human health, ecosystem, or materials concerns. Also, the more regional to global problems of stratospheric ozone depletion, climate change, acidification, and tropospheric ozone production and air pollution are common
From page 189...
... For example, the report on India devoted considerable attention to the health hazards of chemicals, both in the workplace and in accidental leakages, largely because at the time of the report the Bhopal disaster was still a major environmental event. Overall, these analyses suggest that, for most nations of the world, water and air pollution are the top priority issues; for most of the more industrialized nations, ozone depletion and climate change are also ranked highly; while for many of the less-industrialized countries, droughts or floods, disease epidemics, and the availability of local living resources are crucial.
From page 190...
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From page 191...
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From page 192...
... In addition, we evaluated progress over the last decade in achieving the measures identified by the Brundtland "challenges. " Human Population and Well-Being In 1987, the Brundtland Commission framed the issue of human population growth in terms of both the balance between population and resources and the need for increased health, well-being, and human rights to self-determination.
From page 193...
... Because of human introductions nearly TA~E i>2 Projections of the Population Size of the Developing World With and Without Unwanted Births Projection Projected population size (billions) in year 2050 2100 Standard*
From page 194...
... For example, reduction in industrial wastes through approaches using industrial ecology would have large advantages for human health, and also for the environment as it is affected by energy and water sectors, through the increased efficiency of these resources' use. Finally, the maintenance of natural ecosystems and the protection of their services can influence human health in many ways, including by providing natural enemies for disease vectors and natural water and air purification and supply systems.
From page 195...
... Access to water and sanitation services also present enormous challenges to rapidly growing cities. Despite concerted efforts during the 1980s, designated the "International Drinking Water Supply and Sanitation Decade" by the World Health Organization, in 1990 about 200 million urban dwellers were without a safe water supply, and around 400 million were without adequate sanitation.~7 In the largest cities of the industrializing world, the poorest populations in the slums and at the city margins tend to have the least access to safe water.
From page 196...
... The study made recommendations on management of water supply through metering and pricing mechanisms, needed research, treatment of municipal wastewater prior to disposal, demand management approaches, a comprehensive groundwater protection program, a variety of water reclamation schemes, and possible institutional changes related to applying a new cultural perspective to the value of water in Mexico City.20 It is noteworthy that this comprehensive study recommended several approaches to improved management and conservation of water and none involving further resource development. as Mexico City (see Box 4.1)
From page 197...
... Such growth is not now in progress nor is it projected for the foreseeable future. The Brundtland Commission recognized that a great strategic effort would be required to meet the challenge of feeding a growing population, yet the past 10 years have seen a reduction in resources for the international agricultural research community along with indicator values that increasingly show world capabilities for increasing food production are stagnating.24 During the last half century, the dramatic gains in crop production that have occurred almost worldwide (except, in particular, Sub-Saharan Africa)
From page 198...
... Together, these biophysical factors threaten achieving a successful transition toward sustainability. Perhaps more important still are the threats associated with inadequate investment in the agricultural sector now for research, education, technological developments, and transfer of knowledge and information to the developing world.30 Local agricultural research capacity, local public and private capacity to make knowledge, technology, and materials available to producers, and the schooling or informal education of farmers and farm workers are all required for sustained growth in agricultural production.
From page 199...
... For example, integrated nutrient management, like integrated pest management, takes advantage of the ecological processes operating in soils and crop ecosystems and uses them in combination with industrial inputs to optimize productivity and reduce pesticide and nutrient spread.33 Ecologically based pest management takes advantage of biological diversity to reduce the need for pesticide use. Increased use of efficient irrigation systems will conserve and maintain water supplies and lessen competition with urban and other uses.34 In breeding programs, increasing attention to flexibility and genetic diversity of crop plants can increase the ability of the agricultural sector to respond to climate and other environmental "surprises."35 The development of management systems and breeding programs for regional staple crops could also enlarge the food security basket for the poor in many regions.
From page 200...
... Nevertheless, global production, consumption, and circulation of many toxic metals and organics have increased dramatically in the last half century because of their utility in many industrial activities, though production began to level off in the early 1970s and emissions began to decline (Figure 4.1~. But numerous opportunities exist to reduce material usage as well as
From page 201...
... . Beyond the challenges related to the reduction and elimination of industrial wastes, the rapidly changing industrial trajectory carries with it the general problem of anticipating problems in new industries and of projecting the dynamics of employment into a future with many more people.
From page 202...
... Nonetheless, the current trends toward production of more by fewer people could lead to persistent unemployment of an expanded population, a spectre not foreseen by the Brundtland Commission.43 As the preceding paragraphs make clear, industry is faced with many enormous challenges and much responsibility for reducing and preventing environmental problems related to industrial wastes and leakages. At the same time, however, it also faces a tremendous opportunity for massive market expansion, the development of new technologies (and, therefore new product possibilities, even beyond the products for which the technologies were developed)
From page 203...
... The world will need to find a way that allows 9 billion people or more to enjoy a lifestyle that requires energy while at the same time protects and sustains human health and the health of the biosphere from local to global scales. Numerous environmental hazards, including climate change, acidification of water and soil, and air pollution, stem from our dependence on fossil fuel energy.
From page 204...
... While a shift from coal to natural gas may reduce carbon dioxide emissions, emissions of a still more potent greenhouse gas, methane, could result if natural gas energy systems are not leak-free. Nonfossil energy sources circumvent the serious local, regional, and global air pollution problems of fossil fuels, but each holds its own set of limitations and challenges.46 Most available sources of hydroelectric power have already been developed in industrialized countries.
From page 205...
... This is already apparent in the switch of many electric power systems from coal to gas. If this process is to continue and accelerate, ways must be found to reflect directly or indirectly the full environmental costs of fossil fuel in the market place.
From page 206...
... Living Resources The human population rests its requirements for food, shelter, and other essential goods on the shoulders of earth's living and other resources. The grassland, forest, freshwater and marine ecosystems of the world provide such goods as food, timber, forage, fuels pharmaceuticals, and precursors to industrial products.
From page 207...
... Decimation of pollinating insects has had important negative consequences on yields of particular crops.58 Introductions and invasions of nonnative species such as killer bees, fire ants, and zebra mussels through human activities cause enormous damage to living resources and threaten human health. Clearly, at the heart of the sustainability transition is the challenge to
From page 208...
... Finally, the management of living resources must acknowledge and plan for the links among human and natural systems at the landscape and regional scales; and research, management, and development plans must integrate intensive land and water uses (e.g., for agriculture and cities) in the context of areas managed for conservation, water catchments, and purification, air quality services, and recreation purposes.59 INTERACTION PERSPECTIVES Over the past several decades, most decision making and much research has chosen to treat environmental problems and the human activities associated with them in relatively narrow, discrete categories such as "soil erosion," "fisheries depletion," and "acid rain." This narrow framing of environmental problems is evident in our reviews of "Environmental" and "Development" perspectives presented earlier in this chapter, and in the organization of environmental ministries, regulation, and research administration around the world.
From page 209...
... For example, no longer can we ask about the consequences of climate change on agricultural ecosystems; instead, we must ask about the combined effects of climate change, increased climate variability, elevated carbon dioxide, soil quality changes, crop management changes, and tropospheric and stratospheric ozone changes on crop productivity. Also, it makes little sense to ask how climate change affects one system (e.g., coral reefs)
From page 210...
... 210 En x o be o .
From page 211...
... 211 co co 5o o co u co u · _1 CD O En x o o ~ 55- 5- A 'a 'A co co v JO 5v co ~5o ~ he o 5u 'a 'o ':D $.~ :^ o o ~ ~ ~ m ~m c .= .= cr ·_1 ~ ~o so ~ I ~ ~ ~ ~ .
From page 212...
... As noted in Chapter 2, although there have been slowing water withdrawals, water quality continues to be a concern, particularly in developing countries, and water supply can be regionally or locally scarce. Global numbers suggest adequate per capita water worldwide.
From page 213...
... Computed from UN population data and estimates; water availability data from WRI (1990~. Courtesy of Cambridge University Press.
From page 214...
... Rising sea level can produce saltwater intrusion into freshwater reservoirs. In some regions, current reservoir and water-retaining systems may be unable to maintain water supply during drought periods.
From page 215...
... 21 .q TA~E 4~S Threats to Aquatic Ecosystem Services from Human Activities Human Activity Impact on Aquatic Ecosystems Values/Services at Risk Dam Alters timing and quantity of Habitat, sports, and construction river flows, water temperature, commercial fisheries; nutrient and sediment transport, maintenance of deltas and delta replenishment; blocks fish their economies migrations. Dike and levee Destroys hydrologic connection Habitat, sports, and construction between river and floodplain commercial fisheries; natural habitat floodplain fertility; natural flood control Excessive river Depletes streamflows to Habitat, sports, and diversions ecologically damaging levels commercial fisheries; recreation; pollution dilution; hydropower; transportation Draining of Eliminates key component of Natural flood control, habitat wetlands aquatic environment for fisheries and waterfowl, recreation, natural water filtration Deforestation/ Alters runoff patterns, inhibits Water supply quantity and poor land use natural recharge, fills water quality, fish and wildlife bodies with silt habitat, transportation, flood control Uncontrolled Diminishes water quality Water supply, habitat, pollution commercial fisheries, recreation Overharvesting Depletes living resources Sport and commercial fisheries, waterfowl, other living resources Introduction of Eliminates native species, Sport and commercial fisheries, exotic species alters production and nutrient waterfowl, water quality, fish cycling and wildlife habitat, transportation Release of metals Alters chemistry of rivers and and acid-forming lakes pollutants to air and water Habitat, fisheries, recreation Emission of Has potential to make dramatic Water supply, hydropower, climate-altering changes in runoff patterns from transportation, fish and air pollutants increases in temperature and wildlife habitat, pollution changes in rainfall dilution, recreation, fisheries, flood control Population and Increases pressures to dam and Virtually all aquatic ecosystem consumption divert more water, drain more services growth wetlands, etc.; increases water pollution, acid rain, and potential for climate change Source: Daily (1997~.
From page 216...
... The cumulative and interactive consequences of gas emissions associated with industry, fossil fuel consumption, and agriculture are
From page 217...
... and nitrogen oxides (NOx) , in conjunction with nitrogen oxide emissions from the agricultural sector and hydrocarbon emissions from natural forests, combine to affect regionalscale pollution events (Figure 4.3~.73 Such broad-scale pollutant levels may feed back to reduce agricultural productivitys as well as combine to impair human health and the health of natural ecosystems.
From page 218...
... Long-term nitrogen deposition resulting from human activities is likely to damage vegetation, thereby decreasing its carbon uptake. Moreover, nitrogen deposition may also increase the emissions of other greenhouse gases.79 Integrated Strategies for the Atmospheric Environment As for water resources, managing for air quality and for the atmospheric environment requires a different strategy than societies have seen in the past decades.
From page 219...
... , as opposed to other fossil fuels, has been encouraged because of its higher energy yield per molecule of CO2 released in combustion and its lesser impact on regional air quality. On the other hand, methane is a very effective greenhouse gas (about 20 times as potent as CO2 per molecule)
From page 220...
... Ultimately, however, climate and atmospheric changes will alter the structure and composition of ecosystems and the services they provide in unpredictable ways.86 To the degree that our actual development paths involve everincreasing pressures on natural ecosystems, the goals of a transition to sustainability cannot be met. One of the major threats to ecosystem
From page 221...
... For example, numerous opportunities exist for combining management for sustainable forestry and sustainable agriculture with management for biodiversity and ecosystem integrity.87 Management of agricultural landscapes to optimize for natural pollinators and natural predators of agricultural pests will at the same time conserve species and ecosystems, because in doing so patches of diverse natural vegetation adjacent to agricultural systems are maintained. Management of regions to maximize water supply and water quality for urban systems can at the same time conserve and sustain the natural systems that provide watershed services.
From page 222...
... Instead, as summarized by a major restrospective sponsored by the Rockefeller Foundation The location-specific nature of biological technology meant that the prototype technologies developed at the international centers could become available to producers in the wide range of agroclimate regions and social and economic environments in which the commodities were being produced only if the capacity to modify, adapt, and reinvent the technology was available. It became clear that the challenge of constructing a global agricultural research system capable of sustaining growth in agricultural production required the development of research
From page 223...
... In Chapters 5 and 6, we turn to a consideration of the indicators, research, and institutions needed to realize the potential of these analyses. CONCLUSION This analysis shows that progress has been made toward identifying environmental hazards and toward a greater understanding of the challenges in each of the sectors identified 10 years ago by the Brundtland Commission.
From page 224...
... Science 277: 509-515. Brundtland Commission.
From page 225...
... 1997. Nature's services: Societal dependence on natural ecosystems.
From page 226...
... In Nature's Services: Societal dependence on natural ecosystems, ed. Gretchen C
From page 227...
... The Joint Academies Committee on the Mexico City Water Supply. Washington, D.C.: National Academy Press.
From page 228...
... Chap. 8 in Nature's services: Societal dependence on natural ecosystems, ed.
From page 229...
... Stream water quality in the conterminous United States Status and trends of selected indicators during the 1980s. USGS Water Supply Paper 2400.
From page 230...
... A joint publication by the World Resources Institute, the United Nations Environment Programme, the United Nations Development Programme, and He World Bank. New York: Oxford University Press.
From page 231...
... ; municipal solid wastes, EPA (1990)
From page 232...
... , Watt (1966) , and Holling (1978~; recent years, e.g., the World in Transition reports of the German Advisory Council on Global Change (WBGU 1993-1997~; see also Chapter 6, Box 6.1.


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