As part of the studies related to the obligations of the UN Framework Convention on Climate Change, the Republic of Kazakhstan started activities to inventory greenhouse gas (GHG) emissions and assess of GHG mitigation options. The objective of this paper is to present an estimate of the possibility of mitigating GHG emissions and determine the mitigation priorities. It presents a compilation of the possible options and their assessment in terms of major criteria and implementation feasibility. Taking into account the structure of GHG emissions in Kazakhstan in 1990, preliminary estimates of the potential for mitigation are presented for eight options for the energy sector and agriculture and forestry sector. The reference scenario prepared by expert assessments assumes a reduction of CO2 emissions in 1996–1998 by about 26% from the 1990 level due to general economic decline, but then emissions increase. It is estimated that the total potential for the mitigation of CO2 emissions for the year 2000 is 3% of the CO2 emissions in the reference scenario. The annual reduction in methane emissions due to the estimated options can amount to 5%–6% of the 1990 level.
The term "barren hills" has been a keyword for land degradation in the uplands of Vietnam for over a decade. Nevertheless, the "barren" land is still not adequately ecologically characterized. In this work, we analyze land use-induced changes in vegetation and soil properties along a sequence of barren hills types formed on one physiotope. The study is undertaken in the Bac Kan province, one of the poorest upland regions where livestock plays an important role. A transition from an old-growth laurel forest to a sparse manmade grassland is characterized by a total of 177 species, rapid species turnover, and discrete dominants, and an overwhelming effect of disturbance history on both soil and vegetation patterning. Land degradation is most apparent in land use-induced maintenance of arrested successions, and the regeneration course is shifted towards drier formations. We hypothesize a conceptual model as an aid to understanding the process of early fallow differentiation in response to the patterned, fine-scale disturbances. The larger-scale implications of the observed trends in regeneration potentials deviation, and, in particular, the effect of water buffaloes in halting fallow successions, are discussed. 相似文献
Soil and sediment samples from James Ross Island were analyzed for their PCB, OCP and PAH contents. Soil concentrations ranged between 0.51 and 1.82 ng g(-1) for seven indicator PCB congeners, between 0.49 and 1.34 ng g(-1) for HCH congeners, between 0.51 and 3.68 ng g(-1) for the sum of p,p'-DDT, DDE, and DDD, and between 34.9 and 171 ng g(-1) for the sum of 16 EPA PAHs. Sediment levels from 0.32 to 0.83 ng g(-1) were found for PCBs, from 0.14 to 0.76 ng g(-1) for HCHs, from 0.19 to 1.15 ng g(-1) for DDTs, and from 1.4 to 205 ng g(-1) for PAHs. A prevalence of low-mass PAHs, less chlorinated PCBs, and more volatile chemicals indicates that the long-range atmospheric transport from populated areas of Africa, South America, and Australia is the most probable contamination source for the solid matrices in James Ross Island. 相似文献
This article focuses on the governing system of the mitigation of eutrophication in the Baltic Sea. Policies and measures of the Baltic Sea coastal countries, the macro--regional (HELCOM) level, and the level of the European Union are described and governance challenges explicated. We found that the main challenges at different governance levels include: differences between coastal countries in terms of environmental conditions including environmental awareness, overlaps of policies between different levels, the lack of adequate spatial and temporal specification of policies, and the lack of policy integration. To help to meet these challenges, we suggest closer involvement of stakeholders and the public, the improvement of the interplay of institutions, and the introduction of a “primus motor” for the governance of the mitigation of eutrophication in the Baltic Sea. 相似文献
A three-dimensional hydrodynamic model that includes the effect of drag from macrophytes was applied to Conesus Lake to study
the seasonal circulation and thermal structure during spring and early summer. Local weather conditions and stream flow data
were used to drive the model. The drag coefficient for macrophytes was calculated as a function of leaf density. In general,
the model results show good agreements with the observations, including vertical temperature profiles measured at two locations
and average surface temperature derived from calibrated thermal imagery for large-scale simulations of the entire lake. Additional
high-resolution simulations were carried out to understand water circulation and transport of sediment and model-generated
tracer during hydrometeorological events at stream mouths for two experimental sites. The model results show that the plume
development at stream mouths during storm events in Conesus Lake are site-dependent and may either be current- or wind-driven.
The results also show a significant effect from the presence of macrophytes on sediment deposition near stream mouths. 相似文献
Salt efflorescences markedly contribute to the alteration and deterioration of building material, in this case the Villamayor
Sandstone of the facades in the Old Town of Salamanca, Spain (United Nations Educational, Scientific and Cultural Organization
world cultural heritage site). A better understanding of the mechanisms of salt formation and the involved elements would
allow more precise measures in monument conservation. The magnesium which is required for the salt precipitation originates
from selective processes of hydrolysis. The source of sulphate, however, is presently not as clear. Identifying the source
of the sulphur was the main goal of this research. Isotope ratio measurement of δ34S and δ18O was used to clarify the origins of Mg sulphate salts. 相似文献