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41.
小城镇土地利用变化的生态效应分析 总被引:8,自引:3,他引:5
采用系统生态学方法,尤其是应用了Simpson生物多样性指数法,前后相隔10年为时间跨度,对小城镇发展典型地区浙江省绍兴县某镇土地利用变化导致的生态效应进行了初步定量分析与研究.结果表明,由于土地使用功能的改变,导致了以绿色植物为计数的Simpson指数增加近2倍,而以土壤微生物为参照的工业和居住用地的Simpson指数均高于农业用地,反映该小城镇发展过程中生物多样性明显降低,并出现了局部气候的恶化(表现为镇区内年平均气温上升,而年平均相对湿度下降)等不良生态效应. 相似文献
42.
Roland Hischier Stefanie Hellweg Christian Capello Alex Primas 《The International Journal of Life Cycle Assessment》2005,10(1):59-67
Goal, Scope and Background In contrast to inventory data of energy and transport processes, public inventory data of chemicals are rather scarce. Chemicals are important to consider in LCA, because they are used in the production of many, if not all, products. Moreover, they may cause considerable environmental impacts. For these reasons, it was one goal of the new ecoinvent database to provide LCI data on chemicals. In this paper, the methods and procedures used for establishing LCIs of chemicals in ecoinvent are presented.Methods Three different approaches are suggested for situations of differing data availability. First, in the case of good data availability, the general quality guidelines of ecoinvent can be followed. Second, a procedure is proposed for the translation of aggregated inventory data (cumulative LCI results) from industry into the ecoinvent format. This approach was used, if adequate unit process data was not available. Third, a procedure is put forward for estimating inventory data using stoichiometric equations from technical literature as a main information source. This latter method was used if no other information was available. The application of each of the three procedures is illustrated with the help of a case study.Results and Conclusion When sufficient information is available to follow the general guidelines of ecoinvent, the resulting dataset is characterized by a high degree of detail, and it is thus of high quality. For chemicals, however, the application of the standard procedure is possible in only a few cases. When using industrial data, the main drawback is the fact that those data are often available only as aggregated data, thus being out of tune with the quality guidelines of ecoinvent and its main aim, the harmonization of LCI data. As a third approach, the use of the stoichiometric reaction equation is used for the compilation of LCI datasets of chemicals. This approach represents an alternative to neglecting chemicals completely, but it contains a high risk to not consider important aspects of the life cycle of the respective substance.Outlook Further work in the area of chemicals should focus on an improvement of datasets, so far established by either of the two estimation procedures (APME method; estimation based on technical literature) described. Besides the improvement of already established inventories, the compilation of further harmonized inventories of specific types of chemicals (e.g. solvents) or of chemicals for new industrial sectors (e.g. electronics industry) are in discussion. 相似文献
43.
The macrophytes Fucus serratus and Zostera marina form similar substrates for associated flora and fauna in shallow waters in Norway. While F. serratus forms a more or less continuous belt on rocky substrate along the coast, Z. marina forms disjunct populations on sandy or muddy bottoms. This study focused on the organisms associated with these two macrophytes in two localities in the Skagerrak region. In total, 130 taxa of epiphytic organisms were identified: 22 green algae, 41 red algae, 32 brown algae, eight diatoms and 27 sessile animals. One hundred and twenty-seven taxa of mobile macrofauna were registered. The dominant group was crustaceans, with amphipods as the order containing most species. Many species of both plants and animals preferred one or the other habitat. It is concluded that coastal macrophyte systems have high species diversity. 相似文献
44.
Mona Vetter Christian Wirth Hannes Böttcher Galina Churkina Ernst-Detlef Schulze Thomas Wutzler Georg Weber† 《Global Change Biology》2005,11(5):810-827
Temperate forest ecosystems have recently been identified as an important net sink in the global carbon budget. The factors responsible for the strength of the sinks and their permanence, however, are less evident. In this paper, we quantify the present carbon sequestration in Thuringian managed coniferous forests. We quantify the effects of indirect human‐induced environmental changes (increasing temperature, increasing atmospheric CO2 concentration and nitrogen fertilization), during the last century using BIOME‐BGC, as well as the legacy effect of the current age‐class distribution (forest inventories and BIOME‐BGC). We focused on coniferous forests because these forests represent a large area of central European forests and detailed forest inventories were available. The model indicates that environmental changes induced an increase in biomass C accumulation for all age classes during the last 20 years (1982–2001). Young and old stands had the highest changes in the biomass C accumulation during this period. During the last century mature stands (older than 80 years) turned from being almost carbon neutral to carbon sinks. In high elevations nitrogen deposition explained most of the increase of net ecosystem production (NEP) of forests. CO2 fertilization was the main factor increasing NEP of forests in the middle and low elevations. According to the model, at present, total biomass C accumulation in coniferous forests of Thuringia was estimated at 1.51 t C ha?1 yr?1 with an averaged annual NEP of 1.42 t C ha?1 yr?1 and total net biome production of 1.03 t C ha?1 yr?1 (accounting for harvest). The annual averaged biomass carbon balance (BCB: biomass accumulation rate‐harvest) was 1.12 t C ha?1 yr?1 (not including soil respiration), and was close to BCB from forest inventories (1.15 t C ha?1 yr?1). Indirect human impact resulted in 33% increase in modeled biomass carbon accumulation in coniferous forests in Thuringia during the last century. From the forest inventory data we estimated the legacy effect of the age‐class distribution to account for 17% of the inventory‐based sink. Isolating the environmental change effects showed that these effects can be large in a long‐term, managed conifer forest. 相似文献
45.
Wolf M. Mooij Stephan Hülsmann Lisette N. De Senerpont Domis Bart A. Nolet Paul L. E. Bodelier Paul C. M. Boers L. Miguel Dionisio Pires Herman J. Gons Bas W. Ibelings Ruurd Noordhuis Rob Portielje Kirsten Wolfstein Eddy H. R. R. Lammens 《Aquatic Ecology》2005,39(4):381-400
Climate change will alter freshwater ecosystems but specific effects will vary among regions and the type of water body. Here,
we give an integrative review of the observed and predicted impacts of climate change on shallow lakes in the Netherlands
and put these impacts in an international perspective. Most of these lakes are man-made and have preset water levels and poorly
developed littoral zones. Relevant climatic factors for these ecosystems are temperature, ice-cover and wind. Secondary factors
affected by climate include nutrient loading, residence time and water levels. We reviewed the relevant literature in order
to assess the impact of climate change on these lakes. We focussed on six management objectives as bioindicators for the functioning
of these ecosystems: target species, nuisance species, invading species, transparency, carrying capacity and biodiversity.
We conclude that climate change will likely (i) reduce the numbers of several target species of birds; (ii) favour and stabilize
cyanobacterial dominance in phytoplankton communities; (iii) cause more serious incidents of botulism among waterfowl and
enhance the spreading of mosquito borne diseases; (iv) benefit invaders originating from the Ponto-Caspian region; (v) stabilize
turbid, phytoplankton-dominated systems, thus counteracting restoration measures; (vi) destabilize macrophyte-dominated clear-water
lakes; (vii) increase the carrying capacity of primary producers, especially phytoplankton, thus mimicking eutrophication;
(viii) affect higher trophic levels as a result of enhanced primary production; (ix) have a negative impact on biodiversity
which is linked to the clear water state; (x) affect biodiversity by changing the disturbance regime. Water managers can counteract
these developments by reduction of nutrient loading, development of the littoral zone, compartmentalization of lakes and fisheries
management. 相似文献
46.
In a chalk grassland in north-western France, vegetation and seed rain were studied along two transects. We compared the efficiency of three types of seed traps (funnel traps, sticky traps, pots exposed in the field) to estimate the annual seed rain and to reveal various processes involved in plant community regeneration. Data were analysed to compare seed density, species richness and composition across seed traps and vegetation. Geostatistical analyses (semivariograms. were used to detect possible autocorrelation and to examine patterns of spatial variation in seed rain and vegetation. The results show that (1) funnel traps are most efficient (56 species, 8079 seeds.m–2). (2) Each type of seed traps brings different information about the processes involved in seed dispersal and seedling establishment. Sticky traps help to understand import and export of seeds in a community through anemochory. Funnel traps may provide a measure of the auto-regeneration capacity of the vegetation through its local seed production. Pot traps integrate various processes involved between seed dispersal and seedling emergence. (3.) The exposition to environmental conditions generates marked spatial patterns in species richness measured in pots and in vegetation, selecting species able to survive. Pot traps indicate that numerous species producing seeds in standing vegetation are unable to establish in the field through seedling recruitment. Our study emphasizes the need of using different types of seed traps and spatial sampling configurations to assess the regenerative potential of standing vegetation and the various mechanisms involved in seed dispersal. A standardised protocol for seed rain sampling was finally developed. 相似文献
47.
Christos Arvanitidis Georgios Chatzigeorgiou Drosos Koutsoubas Theodoros Kevrekidis Costas Dounas Anastasios Eleftheriou Panayota Koulouri Athanasios Mogias 《Helgoland Marine Research》2005,59(3):177-186
An attempt is made to compare the results of different rapid biodiversity assessment techniques at the pan-Mediterranean, sectorial and local levels. A uniform multivariate pattern exists at the pan-Mediterranean and national (sectorial) levels: lagoons can be different when they host only a few species, but as species numbers increase, lagoons become homogenous in composition. Multivariate techniques cannot distinguish anthropogenically-impacted lagoons from those, which are naturally disturbed. In the pan-Mediterranean context it is the higher taxonomic levels, but in the national and local context it is the most abundant macrobenthic groups (polychaetes, molluscs and crustaceans) and meiobenthos which provide patterns closest to that derived from the species level. Taxonomic distinctness indices applied to polychaete and mollusc inventories provide meaningful results at most levels and scales of observation. These indices seem to be robust enough to discriminate anthropogenically impacted from naturally disturbed lagoons. 相似文献
48.
Rank correlations between tree species diversity in forest stands and parameters of landscape pattern were calculated using data from 4933 locations in Otepää Nature Park. Stand diversity was characterised by the number of tree species in the stand formula and by the index of dominance of tree species’ coverage. Landscape diversity was characterised by locally calculated pattern parameters from three categorical map layers (1:10 000 base map, 1:10 000 soil map, combination of these maps) and from six numerical variables (elevation, slope angle, four channels of a Landsat 7 ETM image).A weak trend appeared for more diverse forest stands to be located in more diverse landscapes according to the base map. Forest stand diversity is also higher on steeper slopes and in places surrounded by slopes of varying steepness. The correlation between landscape diversity and biodiversity depends on the radius of the kernel in which landscape characteristics are calculated. Evidence of an indicative neighbourhood could be seen in many spatial relationships. The spatial correlation between stand diversity and indices calculated from the base map was most visible at distances ranging from 400 to 500 m; surface elevation and its variation correlates with stand diversity at distances of 100–200 m. Some relationships between forest diversity and landscape diversity that had a different sign of correlation in proximate and distant kernels can be interpreted as a need to standardise local landscape indices with the index values in a wider neighbourhood as a reference. 相似文献
49.
China is one of the countries in the world with therichest species biodiversityinfreshwater ecosystem.How-ever,duetothe rapid economic growthandthe continuingincrease of human disturbances and destructions of aquatichabitats,the biodiversity of freshwater ecosystemsis dras-tically declining.Waterbodies become more and more“deserted”of sensitive species.Water areas are reduced,fragmentized,and changed in their hydrodynamics(i.e.damming),causing changes in sedimentation and otherchanges.Forinstance,the area o... 相似文献
50.
Arpad Horvath 《The International Journal of Life Cycle Assessment》2006,11(4):229-239
Goal, Scope and Background This study provides a life cycle inventory of air emissions (CO2, NOx, PM10, and CO) associated with the transportation of
goods by road, rail, and air in the U.S. It includes the manufacturing, use, maintenance, and end-of-life of vehicles, the
construction, operation, maintenance, and end-of-life of transportation infrastructure, as well as oil exploration, fuel refining,
and fuel distribution.
Methods The comparison is performed using hybrid life cycle assessment (LCA), a combination of process-based LCA and economic input-output
analysis-based LCA (EIO-LCA). All these components are added by means of a common functional unit of grams of air pollutant
per ton-mile of freight activity.
Results and Discussion Results show that the vehicle use phase is responsible for approximately 70% of total emissions of CO2 for all three modes.
This confirms that tailpipe emissions underestimate total emissions of freight transportation as infrastructure, pre-combustion,
as well as vehicle manufacturing and end-of-life account for a sizeable share of total emissions. Differences between tailpipe
emissions and total system wide emissions can range from only 4% for road transportation's CO emissions to an almost ten-fold
difference for air transportation's PM10 emissions.
Conclusion Rail freight has the lowest associated air emissions, followed by road and air transportation. Depending on the pollutant,
rail is 50-94% less polluting than road. Air transportation is rated the least efficient in terms of air emissions, partly
due to the fact that it carries low weight cargo. It emits 35 times more CO2 than rail and 18 times more than road transportation
on a ton-mile basis. It is important to consider infrastructure, vehicle manufacturing, and pre-combustion processes, whose
life-cycle share is likely to increase as new tailpipe emission standards are enforced.
Recommendation and Outlook Emission factors, fuel efficiency, and equipment utilization contribute the most to uncertainty in the results. Further studies
are necessary to address all variables that influence these parameters, such as road grade, vehicle speed, and vehicle weight.
A focus on regional variation, end-of-life processes, fuel refining processes, terminals, as well as more accurate infrastructure
allocation between freight and passenger transportation would strengthen the model. 相似文献