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711.
The study deals with the problem of evaluating management strategies for pure stands of Norway spruce (Picea abies Karst) to balance adaptation to and mitigation of climate change, taking into account multiple objectives of a forest owner.
A simulation and optimization approach was used to evaluate the management of a 1000 ha model Age-Class forest, representing
the age-class distribution of an area of 66,000 ha of pure Norway spruce forests in the Black Forest region of Southwest Germany.
Eight silvicultural scenarios comprising five forest conversion schemes which were interpreted as “adaptation” strategies
which aims at increasing the proportion of Beech, that is expected to better cope with climate change than the existing Norway
spruce, and three conventional strategies including a “Do-nothing” alternative classified as “mitigation”, trying to keep
rather higher levels of growing stock of spruce, were simulated using the empirical growth simulator BWINPro-S. A linear programming
approach was adapted to simultaneously maximize the net present values of carbon sequestration and timber production subject
to the two constraints of wood even flow and partial protection of the oldest (nature protection). The optimized plan, with
the global utility of 11,687 €/ha in forty years, allocated a combination of silvicultural scenarios to the entire forest
area. Overall, strategies classified as “mitigation” were favored, while strategies falling into the “adaptation”-category
were limited to the youngest age-classes in the optimal solution. Carbon sequestration of the “Do-nothing” alternative was
between 1.72 and 1.85 million tons higher than the other alternatives for the entire forest area while the differences between
the adaptation and mitigation approaches were approximately 133,000 tons. Sensitivity analysis showed that a carbon price
of 21 €/t is the threshold at which carbon sequestration is promoted, while an interest rate of above 2% would decrease the amount
of carbon. 相似文献
712.
塔式太阳能热电站正常运行时会引发光污染问题。本文分析了塔式太阳能热电站产生光污染的原因以及光污染对人和生态环境产生的危害。在塔式太阳能电站选址、组件设计、安全防护以及配套设施方面,分别提出了有效的光污染防治措施,对于塔式太阳能热电站光污染的防治,提供了一定的理论指导。 相似文献
713.
Lespes G Marcic C Heroult J Le Hecho I Denaix L 《Journal of environmental management》2009,90(Z1):S60-S68
This paper provides quantitative information on the transfer of TBT (tributyltin) and TPhT (triphenyltin) from sludged soil to cultivated lettuce. The effect of their initial concentrations in the soil (varying from 20 to 50 microg(Sn)kg(-1) for each triorganotin), sludge amount (between 1% and 9%), and cultivation duration (32-54 days) was evaluated by means of experimental designs. The impact of the cultivation temperature at 13 degrees C and 19 degrees C on organotin fate in the soil/plant system was also considered. The final concentration of a given organotin in the plant roots was found to depend directly on its initial concentration in the soil. A total of (85+/-15)% of initial TBT in the soil was still present at the end of the experiments, regardless of the cultivation duration. Consequently, TBT appeared to be taken up by lettuce continually. A total of (75+/-5)% of TPhT was found to be degraded in the soil at 54 days. So, this compound could have been taken up by the plant at the beginning of the cultivation. Sludge amount seemed to have a negative effect on TPhT concentration in a plant at 32 days. This could be due to the quantitative TPhT sorption onto the sludge, observed just after spiking. Organotin plant uptake appeared to be more important at 19 degrees C than at 13 degrees C. TBT and TPhT were mainly accumulated in the roots, and up to 2% and 10% of TPhT and TBT, respectively, were translocated to the shoots. Despite TPhT degradation, products in large amounts were present in the soil and were not significantly taken up by the plant. They possibly remained immobilized on solid phases of the sludged soil. 相似文献
714.
Environmental evaluation of transfer and treatment of excess pig slurry by life cycle assessment 总被引:1,自引:0,他引:1
Lopez-Ridaura S Werf Hv Paillat JM Le Bris B 《Journal of environmental management》2009,90(2):1296-1304
Slurry management is a central topic in the agronomic and environmental analysis of intensive livestock production systems. The objective of this study is to compare the environmental performance of two scenarios of collective slurry management for the disposal of excess nitrogen from animal manure. The scenarios are the transfer of slurry and its injection to crop land, and the treatment of slurry in a collective biological treatment station. The study is based on a real case in the West of France, where a group of farmers is developing a collective plan for the disposal of almost 7000 m(3) of excess pig slurry. The evaluation is carried out by Life Cycle Assessment, where emissions and resource consumption are quantified and aggregated into four environmental impact categories: eutrophication, acidification, climate change, and non-renewable energy use. Ammonia emitted is the most important contributor to acidification and eutrophication, while methane contributes most to climate change. Both ammonia and methane are mostly emitted during the storage of slurry and, in the case of the treatment scenario, also during composting the solid fraction of the slurry. The two management strategies are similar with respect to climate change, whereas eutrophication and acidification are twice as large for treatment relative to transfer. Electricity needed for the treatment process is the main contributor to non-renewable energy use for the treatment scenario, while the transfer scenario represents a net energy saving, as energy saved by the reduction of mineral fertiliser use more than compensates for the energy needed for transport and injection of slurry. The overall environmental performance of transfer is better than that of treatment, as it involves less acidification, eutrophication and non-renewable energy use. The method employed and the results obtained in this study can provide elements for a transparent discussion of the advantages and disadvantages of contrasting excess slurry management scenarios as well as the identification of the main aspects determining their environmental performance. 相似文献
715.
Human perception of in-channel wood can influence decision-making about wood reintroduction in watercourses for restoration purposes. A questionnaire survey was conducted among first-year and advanced Polish students and professionals involved in the management and protection of watercourses in Poland. The purpose was to assess their perception of river scenes with and without wood in terms of naturalness, aesthetics, danger and need for improvement. Generally, students perceived riverscapes with wood to be less aesthetic, more dangerous and needing more improvement than riverscapes without wood. However, many aspects of the riverscape perception are subject to changes as the student progresses in studying. The culturally conditioned, negative perception of in-channel wood is reduced during the education of geography and biology students but enhanced in the course of water engineering studies. The improved perception of watercourses containing wood was most pronounced for the advanced geography students from a university in which some tutors conducted research on in-channel wood and could have transferred knowledge about and positive attitudes toward wood to their students. A comparison of the riverscape evaluation by biology students and national park managers indicates that education in the discipline facilitates understanding of the environmental significance of in-channel wood although its effects are highly insufficient to form the positive attitude toward wood-containing watercourses typical of the managers. In turn, the education of water engineering students about in-channel wood apparently dominantly emphasizes threats caused by its presence in watercourses, so that the students' highly negative attitude toward wood needs to be significantly moderated when the graduates begin working as water authority managers. 相似文献
716.
Antignac JP Cariou R Zalko D Berrebi A Cravedi JP Maume D Marchand P Monteau F Riu A Andre F Le Bizec B 《Environmental pollution (Barking, Essex : 1987)》2009,157(1):164-173
In the frame of a French monitoring program, tri- to deca- polybromodiphenylethers (PBDE) have been measured in maternal and cord serum, adipose tissue, and breast milk samples, collected from 93 volunteer women during caesarean deliveries. The seven major tri- to heptaBDE (BDE-28, 47, 99, 100, 153, 154, and 183) were detected in adipose tissue and breast milk with cumulated median values of 2.59 and 2.51 ng g−1 l w. Nine highly brominated octa- to decaBDE (BDE-196, 197, 201, 202, 203, 206, 207, 208 and 209) was performed in the same samples, with cumulated median values of 2.73 and 3.39 ng g−1 l w in adipose tissue and breast milk, respectively. At this opposite, median levels of octa- to decaBDE in maternal and cord serum appeared significantly higher than the levels of tri- to heptaBDE in the same matrices, i.e. 8.85 and 12.34 versus 0.98 and 0.69 ng g−1 l w, respectively. 相似文献
717.
Ozone risk assessment for plants: central role of metabolism-dependent changes in reducing power 总被引:2,自引:0,他引:2
Dizengremel P Le Thiec D Bagard M Jolivet Y 《Environmental pollution (Barking, Essex : 1987)》2008,156(1):11-15
The combination of stomatal-dependent ozone flux and total ascorbate level is currently presented as a correct indicator for determining the degree of sensitivity of plants to ozone. However, the large changes in carbon metabolism could play a central role in the strategy of the foliar cells in response to chronic ozone exposure, participating in the supply of reducing power and carbon skeletons for repair and detoxification, and modifying the stomatal mode of functioning. To reinforce the accuracy of the definition of the threshold for ozone risk assessment, it is proposed to also consider the redox pool (NAD(P)H), the ratio between carboxylases and the water use efficiency as indicators of the differential ozone tolerance of plants. 相似文献
718.
719.
Nghiem le H Kim Oanh NT 《Journal of the Air & Waste Management Association (1995)》2008,58(10):1341-1350
This paper presents the first attempt to apply the Mesoscale Meteorological Model (MM5)-Community Multi-Scale Air Quality Model (CMAQ) model system to simulate ground-level ozone (O3) over the continental Southeast Asia (CSEA) region for both hindcast and forecast purposes. Hindcast simulation was done over the CSEA domain for two historical O3 episodes, January 26-29, 2004 (January episode, northeast monsoon) and March 24-26, 2004 (March episode, southwest monsoon). Experimental forecast was done for next-day hourly O3 during January 2006 over the central part of Thailand (CENTHAI). Available data from 20 ambient monitoring stations in Thailand and 3 stations in Ho Chi Minh City, Vietnam, were used for the episode analysis and for the model performance evaluation. The year 2000 anthropogenic emission inventory prepared by the Center for Global and Regional Environmental Research at the University of Iowa was projected to the simulation year on the basis of the regional average economic growth rate. Hourly emission in urban areas was prepared using ambient carbon monoxide concentration as a surrogate for the emission intensity. Biogenic emissions were estimated based on data from the Global Emissions Inventory Activity. Hindcast simulations (CSEA) were performed with 0.5 degree x 0.5 degree resolution, whereas forecast simulations (CENTHAI) were done with 0.1 degree x 0.1 degree hourly emission input data. MM5-CMAQ model system performance during the selected episodes satisfactorily met U.S. Environmental Protection Agency criteria for O3 for most simulated days. The experiment forecast for next-day hourly O3 in January 2006 yielded promising results. Modeled plumes of ozone in both hindcast and forecast cases agreed with the main wind fields and extended over considerable downwind distances from large urban areas. 相似文献
720.
Eutrophication of Lake Waters in China: Cost, Causes, and Control 总被引:21,自引:0,他引:21
Lake water eutrophication has become one of the most important factors impeding sustainable economic development in China.
Knowledge of the current status of lake water eutrophicatoin and determination of its mechanism are prerequisites to devising
a sound solution to the problem. Based on reviewing the literature, this paper elaborates on the evolutional process and current
state of shallow inland lake water eutrophication in China. The mechanism of lake water eutrophication is explored from nutrient
sources. In light of the identified mechanism strategies are proposed to control and tackle lake water eutrophication. This
review reveals that water eutrophication in most lakes was initiated in the 1980s when the national economy underwent rapid
development. At present, the problem of water eutrophication is still serious, with frequent occurrence of damaging algal
blooms, which have disrupted the normal supply of drinking water in shore cities. Each destructive bloom caused a direct economic
loss valued at billions of yuan. Nonpoint pollution sources, namely, waste discharge from agricultural fields and nutrients
released from floor deposits, are identified as the two major sources of nitrogen and phosphorus. Therefore, all control and
rehabilitation measures of lake water eutrophication should target these nutrient sources. Biological measures are recommended
to rehabilitate eutrophied lake waters and restore the lake ecosystem in order to bring the problem under control. 相似文献