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981.
Kenneth T. Gillingham Steven J. Smith Ronald D. Sands 《Mitigation and Adaptation Strategies for Global Change》2008,13(7):675-701
In the coming century, modern bioenergy crops have the potential to play a crucial role in the global energy mix, especially
under policies to reduce carbon dioxide emissions as proposed by many in the international community. Previous studies have
not fully addressed many of the dynamic interactions and effects of a policy-induced expansion of bioenergy crop production,
particularly on crop yields and human food demand. This study combines an updated agriculture and land use (AgLU) model with
a well-developed energy-economic model to provide an analysis of the effects of bioenergy crops on energy, agricultural and
land use systems. The results indicate that carbon dioxide mitigation policies can stimulate a large production of bioenergy
crops, dependent on the level of the policy. This production of bioenergy crops can lead to several impacts on the agriculture
and land use system: decreases in forestland and unmanaged land, decreases in the average yield of food crops, increases in
the prices of food crops, and decreases in the level of human demand of calories.
相似文献
Steven J. Smith (Corresponding author)Email: |
982.
Xochitl Cruz-Núñez Luis Conde Luis G. Ruiz-Suárez 《Mitigation and Adaptation Strategies for Global Change》2008,13(2):179-191
Intergovernmental Panel on Climate Change (IPCC) Tier 1 key sources level 1 assessment was applied to the 1994–1994 National
Greenhouse Gases (GHG) emission inventory for Mexico in order to identify and analyze the key sources within it. Top key sources
were from land use change and energy combustion contributing to about 60% of total national emissions. In addition, a Tier
1 trend assessment revealed some changes with respect to Tier 1 level assessment: Top key sources according to this analysis
are waste disposal and delayed emissions from land clearing. Important insight for cost effective preventive mitigation actions
can be extracted from this analysis. A comparison with other countries was carried out to find similarities in the GHG national
emissions inventories related to common features on economic development. 相似文献
983.
The Kyoto Protocol relies on incentive-based regulations layered underneath a global cap on net emissions of greenhouse gases.
Within the Kyoto Protocol are opportunities and constraints for signatory nations. Of concern to developing nations are the
constraints the Kyoto Protocol could place on future growth. We examine the constraints and the opportunities offered to developing
countries within the Kyoto Protocol. By identifying the potential costs and benefits the Kyoto Protocol has to offer to developing
countries and by examining the incentives each create, we hope to spark serious investigations into ways to minimize the potential
costs of entering the Kyoto Protocol and take full advantage of the potential benefits.
相似文献
Amin SarkarEmail: |
984.
Michael H. Huesemann Joyce A. Huesemann 《Environment, Development and Sustainability》2008,10(6):787-825
Industrial society will move towards collapse if its total environmental impact (I), expressed either in terms of energy and
materials use or in terms of pollution, increases with time, i.e., dI/dt > 0. The traditional interpretation of the I = PAT
equation reflects the optimistic belief that technological innovation, particularly improvements in eco-efficiency, will significantly
reduce the technology (T) factor, and thereby result in a corresponding decline in impact (I). Unfortunately, this interpretation
of the I = PAT equation ignores the effects of technological change on the other two factors: population (P) and per capita
affluence (A). A more heuristic formulation of this equation is I = P(T)·A(T)·T in which the dependence of P and A on T is
apparent. From historical evidence, it is clear that technological revolutions (tool-making, agricultural, and industrial)
have been the primary driving forces behind successive population explosions, and that modern communication and transportation
technologies have been employed to transform a large proportion of the world’s inhabitants into consumers of material- and
energy-intensive products and services. In addition, factor analysis from neoclassical growth theory and the rebound effect
provide evidence that science and technology have played a key role in contributing to rising living standards. While technological
change has thus contributed to significant increases in both P and A, it has at the same time brought about considerable eco-efficiency
improvements. Unfortunately, reductions in the T-factor have generally not been sufficiently rapid to compensate for the simultaneous
increases in both P and A. As a result, total impact, in terms of energy production, mineral extraction, land-use and CO2 emissions, has in most cases increased with time, indicating that industrial society is nevertheless moving towards collapse.
The belief that continued and even accelerated scientific research and technological innovation will automatically result
in sustainability and avert collapse is at best mistaken. Innovations in science and technology will be necessary but alone
will be insufficient for sustainability. Consequently, what is most needed are specific policies designed to decrease total
impact, such as (a) halting population growth via effective population stabilization plans and better access to birth control
methods, (b) reducing total matter-energy throughput and pollution by removing perverse subsidies, imposing regulations that
limit waste discharges and the depletion of non-renewable resources, and implementing ecological tax reform, and (c) moving
towards a steady-state economy in which per-capita affluence is stabilized at lower levels by replacing wasteful conspicuous
material consumption with social alternatives known to enhance subjective well-being. While science and technology must play
an important role in the implementation of these policies, none will be enacted without a fundamental change in society’s
dominant values of growth and exploitation. Thus, value change is the most important prerequisite for avoiding global collapse.
相似文献
Michael H. HuesemannEmail: |
985.
Ian Calder Ashvin Gosain M. S. Rama Mohan Rao Charles Batchelor M. Snehalatha Emma Bishop 《Environment, Development and Sustainability》2008,10(4):537-557
This paper recommends a revision of watershed development policy in India in relation to the planning of development interventions
involving agricultural intensification and rainwater harvesting following biophysical and societal impact studies carried
out on two watershed development projects in Karnataka. A need for changes in policy has arisen in response to progressive
catchments closure at the basin level and declining volumes of water flowing into village level reservoirs (known locally
as tanks). Flow reductions have occurred largely as a result of increased agricultural intensification over the past 10–15 years.
Field levelling, field bund construction, soil water conservation measures, farm ponds, the increase in areas under horticulture
and forestry and the increased abstraction and use of groundwater for irrigation are all contributing factors to reduced flows.
Planning methodologies and approaches, which may have been appropriate 20 years ago for planning water harvesting within watershed
development projects, are no longer appropriate today. New planning approaches are required which (1) take account of these
changed flow conditions and (2) are also able to take account of externalities, which occur when actions of some affect the
livelihoods of others who have no control or influence over such activities and which (3) contribute to the maintenance of
agreed minimum downstream flows for environmental and other purposes.
相似文献
Ian CalderEmail: |
986.
Water samples from zones with different levels of anthropogenic pollution in Peter the Great Bay, the Sea of Japan, were subjected to biotesting on the microalga Dunaliella salina. A distinct inhibitory effect on microalgal cultures was revealed in tests of water from Amur Bay. Water samples from stations in the Tumannaya River mouth and off Frugelm Island (in the southwestern part of Peter the Great Bay) and from Gaidamak Bight (Vostok Bay) had little effect on D. salina growth. 相似文献
987.
Yu. A. Galysheva 《Russian Journal of Ecology》2008,39(4):272-278
The composition and structure of the Gray mussel (Crenomytilus grayanus) community in Vostok Bay of the Sea of Japan have been studied. A total of 165 species have been identified in the macrobenthos. Its species composition has changed insignificantly since the 1970s. The total biomass of the biocenosis has decreased, and the size-age composition of the C. grayanus population has changed due to poaching. The trophic structure of the community has also changed, with the Shannon indices of species diversity and equitability (E) becoming lower, due to intensive organic pollution of Vostok Bay resulting from increasing recreational activities and sewage discharge. 相似文献
988.
The effect of γ irradiation at doses of 1, 5, 10, and 20 kGy on the microflora of ordinary chernozem soil has been studied. The time course of the restoration of the microorganism numbers over 180 days after γ irradiation has been studied in model experiments. The microorganism radioresistance decreases in the following order: amylolytic bacteria > Azotobacter > spore-forming bacteria > ammonifiers > micromycetes. A dose of 20 kGy has a 96% suppressing effect on all microorganisms. Model experiments on the restoration of the irradiated soil microflora have revealed different rates of increase in the numbers of microorganism groups depending on the dose and incubation time. 相似文献
989.
Changes in the main climatic factors (air temperature and total precipitation) and their effect on the radial increment of Scots pine (Pinus sylvestris L.) over the period from 1933 to 2002 were studied in an insular pine forest growing in the steppe zone of the Southern Urals. Evidence for a significant increase in the amount of precipitation and air temperature in the second half of this period was obtained. Functions of response of radial increment indices to climatic parameters were analyzed. Relative contributions of air temperature and precipitation to variation in the radial increment of pine in different time intervals proved to differ in relation to climate changes during the past century. 相似文献
990.
T. A. Moskalyuk 《Russian Journal of Ecology》2008,39(2):73-82
Specific ecological features of trees (Chosenia arbutifolia and Betula lanata) and shrubs (Pinus pumila and Duschekia fruticosa) at the northern limit of their distribution are compared. New biomorphological adaptations of these species under extreme conditions are described. 相似文献