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941.
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.
Michael H. HuesemannEmail:
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942.
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.
Ian CalderEmail:
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943.
944.
The selective catalytic reduction (SCR) rate of NO with N-containing reducing agents can be enhanced considerably by converting part of NO into NO2. The enhanced reaction rate is more pronounced even at lower temperatures by using an equimolar mixture of NO and NO2 (fast SCR reaction). The oxidation characteristics of NO over catalyst Pt/TiO2 have been determined in a fixed bed reactor (8 mm-ID) with different concentrations of oxygen, nitric oxide and nitrogen dioxide in the presence of 8% water. The conversion of NO to NO2 increases with increasing oxygen (O2) concentration from 3 to 12%, but it levels off at higher O2 concentrations. The NO conversion to NO2 decreases with increasing NO concentration and it also decreases by an addition of NO2 in the feed stream. Therefore, the oxidation of NO over Pt/TiO2 catalyst could be auto-inhibited by the reaction product of NO2. The effects of CO and SO2 on NO oxidation characteristics have also been determined. In fact, the presence of SO2 significantly suppresses oxidation of NO but due to the less stability of sulfate on anatase structure in TiO2, it becomes less significant. On the other hand, the presence of CO increases NO oxidation significantly due to the auto-inhibition effect by CO. Moreover, the effect of SO2/CO on NO oxidation has also been determined and it was observed that NO oxidation decreases with the increase in SO2/CO ratio.  相似文献   
945.
Over the past decades, strong evidence has accumulated that low-frequency electromagnetic fields (EMFs) can be useful in treating human pathologies, such as bone fractures, soft tissue illnesses, and pain. Common strategies for the design of commercial therapeutic devices are to generate EMFs that simulate body endogenous EMFs, or EMFs that resonate with a particular biological process, such as the natural motions of ions. We recently came across a biologically active commercial EMF signal that seems to be different. The signal is generated by summing the fundamental frequencies and harmonics of several periodic base signals which remain proprietary to the company. When first examined in the time domain, the signal resembled electronic noise; however, when critically analyzed, the signal is not identical with noise. Rather, it is a highly complex waveform exhibiting a very wide range of values for the time derivative of the magnetic field density (dB/dt) and a beat frequency in the Extremely Low-Frequency range. In this paper, we speculate on the mechanism of action of this and similar signals. We consider it less likely that cells, or cell components, act like filters to extract and couple with individual signals that make up the complex EMF signal. Consequently, we favor the possibility that with the signal discussed here cells respond to the very complex signal and that the biological response can be modified by the presence of a beat in the signal, in this case a low-frequency beat. More generally, this would suggest the hypothesis that biological processes can be regulated by noise-like signals and that the effects of a noisy signal can be modified by the presence of signal repetition patterns, such as beats. Given the very small energy that signals like these can transduce into a biological system, biological effects can be expected only when the molecular processes involved are poised so that the available energy leads to molecular reactions that achieve the activation state for the reaction.  相似文献   
946.
Natural and man-made magnetic and electromagnetic fields are important factors in the contemporary life. The paper discusses the role of environmental magnetic and electromagnetic fields in origin and evolution of life. A brief review of the characteristics of Earth magnetic field, Earth magnetosphere, and their role as a shield for cosmic radiation follows. The role of endogenous and exogenous magnetic fields is discussed in respect of the clarification of the potential hazard and benefit of electromagnetic fields. The second part of the paper discusses the mechanisms of detection and response to exogenous electromagnetic fields, as well as threshold versus window hypothesis for mechanisms of interactions. Finally, the necessity of accurate dosimetry at the target site and the importance of relevant research and clinical protocols in studying biological responses are pointed out.  相似文献   
947.
948.
Throughout the world there is a general consensus among environmentalists that there should be an increase in the amount of marine area that should be reserved in marine protected areas (MPAs). In fact, the 1998 Philippines Fishery Code indicates a need for designation of at least 15% of municipal waters for fish refuges or sanctuaries. Such an increase in area would take productive fishing areas away from fishing communities that can ill-afford the loss. The larger the protected area, there will be a greater number of people impacted. This article examines the relationship between factors that influence the success of Community Based MPA (CBMPA) performance in the Visayas, Philippines and their significance in efforts to increase the size of protected areas.  相似文献   
949.
Cetacean-focused tourism in Taiwan has grown rapidly since 1997. This development, measured in terms of both number of tour boats and visitors, has resulted in many resource management challenges stemming from the absence of regulation and scientific data. To fill this void in empirical evidence, we used 464 sighting records from 2002 to 2005 to model the impact of cetacean-focused tourism. Cox proportional hazard analysis indicated cetacean avoidance responses to cetacean watching boats were strongly associated with pod size, mother–calf pairs, and cetacean-vessel distances. Mother–calf pairs abandoned their avoidance tactic by 55% compared to noncalf groups when tour boats approached. Second, the hazard ratio of abundance was 0.996, suggesting that the odds of encountering avoidance responses by the cetaceans decreased by 42% for every 100-member increase in the cetacean pod size. Last, distances maintained by boats from the cetaceans was positively related to avoidance responses (i.e., less avoidance behavior with closer interaction). Based on our findings, we have the following recommendations: (a) limit vessels from approaching mothers with calves, (b) limit vessels from approaching small groups of cetaceans, (c) reduced avoidance behavior to boat traffic may be a red flag for potential long-term disturbance, and (d) apply the “precautionary principle” based on the best scientific information available in cetacean-based tourism in Taiwan. These recommendations will help contribute to the sustainable development of cetacean-focused tourism in Taiwan.  相似文献   
950.
This article examines one MPA—the Gulf of Mannar National Park and Biosphere Reserve—located in southern India, and four types of social conflict that have surrounded its establishment. Taking the strength of wellbeing aspirations as point of departure, we focus on two themes: the implications of MPA embeddedness in wider societal systems, and the consequences of natural and social variety for governance. We conclude first of all that conflict resolution depends on MPA authorities’ willingness to engage with the interferences that emerge from outside the MPA area. Secondly, we point out the varying wellbeing aspirations of the population and the need to develop governance partnerships. The latter are argued to contribute to more balanced decision making, as well as to a greater appreciation among the target population of the ‘fairness’ of MPA policy.  相似文献   
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