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991.
Pinus roxburghii (chir-pine) and Quercus leucothchophora (banj-oak) are dominant forests of mountainous part of the Uttarakhand Himalaya. The continued anthropogenic disturbance
is opening the canopy, forming canopy gaps and as a result forest fragments are developing. Thus, the present study aims to
analyze variations in species richness and vegetational parameters in relation to canopy gaps in forests. Total species richness
was greater in open canopied forest compared to moderate and close canopied forests. In comparison between oak and pine forest,
it was greater in oak forest while the proportion of common species was low between oak—pine forests. Mean species richness
did not significantly vary from one canopy gap to another as well as in oak and pine dominated forest. This indicated that
dominant forest types played an important role to form the community structure. The shrubs richness were greater in closed
canopy and between the forests it was greater in pine forest. Tree and shrub density was low in open canopy while herb density
was high in moderate canopy. Thus, this study indicated that the dominant canopy species play an important role in deciding
the community structures especially the distribution of under canopy species. These parameters should be considered for conservation
and maintenance of plant biodiversity of a region. 相似文献
992.
There is much discussion within the sustainable development community regarding climate stabilization and particularly, finding
environmentally equitable ways to address emission reductions. Knowing the current level of emission is only one variable
in this complex picture. While the rate of emissions is clearly a problem, the overall increase in GHG concentration in the
atmosphere is ultimately the main driver of anthropogenic warming. Therefore, it is also important to understand the cumulative
emissions, those which have taken us to the current condition. This research presents a case study of six countries to compare
the emissions per capita and cumulative emissions during the past 200 years. It is known that carbon emissions are closely
related to economic activities, but here we show that some countries have reached per capita emissions plateaus at different
levels while others are still rising. Specifically, one approach toward socioeconomic development, in terms of energy–economy,
reaches a plateau at 10 Mt carbon per person, which the United Kingdom and South Korea have attained. The US occupies another
emission regime at 20 Mt carbon per person. Developing economies such as India and China are considerably below these levels,
and unless they follow other integrated economic/environmental solutions, they will continue to increase their per capita
emissions during development. 相似文献
993.
Keigo Akimoto Fuminori Sano Takashi Homma Kenichi Wada Miyuki Nagashima Junichiro Oda 《Sustainability Science》2012,7(2):157-168
This study focuses on analyses of greenhouse gas (GHG) emission reductions, from the perspective of interrelationships among
time points and countries, in order to seek effective reductions. We assessed GHG emission reduction potentials and costs
in 2020 and 2030 by country and sector, using a GHG emission reduction-assessment model of high resolution regarding region
and technology, and of high consistency with intertemporal, interregional, and intersectoral relationships. Global GHG emission
reduction potentials relative to baseline emissions in 2020 are 8.4, 14.7, and 18.9 GtCO2eq. at costs below 20, 50, and 100 $/tCO2eq., corresponding to +19, −2, and −7 %, respectively, relative to 2005. The emission reduction potential for 2030 is greater
than that for 2020, mainly because many energy supply and energy-intensive technologies have long lifetimes and more of the
current key facilities will be extant in 2020 than in 2030. The emission reduction potentials in 2030 are 12.6, 22.0, and
26.6 GtCO2eq. at costs below 20, 50, and 100 $/tCO2eq., corresponding to +19, −2, and −7 %, respectively, relative to 2005. The emission reduction potential for 2030 is greater
than that for 2020, mainly because many energy supply and energy-intensive technologies have long lifetimes and more of the
current key facilities will be extant in 2020 than in 2030. The emission reduction potentials in 2030 are 12.6, 22.0, and
26.6 GtCO2eq. at costs below 20, 50, and 100 /tCO2eq., corresponding to +33, +8, and −3 %, respectively, relative to 2005. Global emission reduction potentials at a cost below
50 $/tCO2eq. for nuclear power and carbon capture and storage are 2.3 and 2.2 GtCO2eq., respectively, relative to baseline emissions in 2030. Longer-term perspectives on GHG emission reductions toward 2030
will yield more cost-effective reduction scenarios for 2020 as well. 相似文献
994.
Ramiz M. Mamedov Boyukagha N. Mustafayev 《Environment, Development and Sustainability》2007,9(2):131-142
In order to determine the potential for sustainable regional development of the Caspian coastal zone, a study was made for
the Khachmaz–Absheron zone of Azerbaijan. An evaluation was performed to assess the anthropogenic load on landscapes. Using
the 8-point scale offered by Isachenko [2001, Ecological Geography of Russia, Saint Petersburg University Press, Saint Petersburg]
for the indicators of agricultural, industrial, urban and integral anthropogenic loads, we did a preliminary ranking of the
provinces in the Khachmaz–Absheron zone of Azerbaijan for the each indicator taken separately. Vital statistics were used
as a supplementary indicator of environmental conditions in the region. By comparing the data for provinces with each other
and the data on Azerbaijan average, we have classified the provinces into 4 groups according to specific combinations of the
indicators. Each group of provinces has distinctive environmental conditions and features for sustainable development. The
classification makes it possible to develop certain recommendations for the regional sustainable development. Measures to
be implemented within the Azerbaijan State Program on Social and Economic Development of Regions are also discussed. In the
Khachmaz province, production of ecologically pure products is highly recommended. Special attention should be given to the
development of tourism and recreational institutions in the Khachmaz, Khizi and Devechi provinces. Recommendations for these
provinces include further development of industry on the basis of modern safe technologies. The irrigation and drainage networks
should be reconstructed. The reconstruction will make it possible to reduce water loss and to increase the productivity of
agriculture. In the Absheron province, Baku and Sumgait cities environmental systems are overloaded, and so the works at highly
polluting enterprises must be stopped, the enterprises have to be re-equipped (old filters must be changed first of all) or
relocated from the area (a decrease of environmental risk should be in the focus of attention). For improving of air quality,
green areas should increase. There is a need to reduce urban traffic density and to reconstruct highways. Use of old vehicles
must be forbidden or restricted, and transition to environmentally friendly fuel should be supported in every way possible.
It is necessary to bring the waste management system and sanitary landfills up to international standards, and to improve
the water supply and sewerage systems. 相似文献
995.
Fabio Orecchini 《Sustainability Science》2007,2(2):245-252
Human society consumes resources that it is not able to reproduce. Human activities are still based on “open cycles,” starting
from a condition of natural environmental balance and reaching an environmental imbalance. The challenging scope of scientific
and technological research towards sustainability appears clear if it is based on this analysis: to find development systems
based on “closed cycles” of resources. The challenging objective of realizing closed cycles leads to a definition of sustainability
that indicates the path to sustainable development, as well as stating the general principle. It also provides a key to the
qualitative measurement of sustainability. This means that the sustainability level of a system can be measured by measuring
its capacity to avoid the consumption of resources. Zero consumption is a necessary condition for sustainability, and brings
about as a side effect the highly desired “zero-waste” result. Materials entering the proposed endless scheme pass through
the process of usefulness without losing their capacity to feed the system again after being used. Thus, the concept of “consumption”
itself is replaced by one of “use” when resources are inserted into closed loops capable of feeding human development. The
application of the closed cycle sustainability criterion particularly displays its feasibility, and a theoretical guiding
role, in the energy sector. Energy vectors such as hydrogen and electricity enable the closure of the energy resources loop
by effectively approaching the objective of “zero consumption” (and the side result of “zero waste”) through already demonstrated
technological solutions. 相似文献
996.
997.
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: |
998.
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: |
999.
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: |
1000.
Tanay B. Yıldırım Tutku Ak Zuhal Ölmez 《Environment, Development and Sustainability》2008,10(6):871-881
While the world is going into different tourism expectations, the tourism understanding in Turkey is defined as tourism in the sea-sand-sun triangle. However, it is possible to contribute to the income and local development of the indigenous people by developing nature-based tourism. Besides, with the sustainable use and preservation of the natural-cultural assets, the damage of the traditional tourism industry on the natural and cultural environment could be reduced. In this study, it is aimed to bring up the nature-based tourism concept in Çanakkale by evaluating the nature-based tourism industry in the general of Turkey and assessing the natural-cultural resources that Çanakkale comprehends. The most important areas that have a nature-based tourism potential in Çanakkale and the tourism activities that are most suitable for these areas have been determined. 相似文献