共查询到20条相似文献,搜索用时 15 毫秒
1.
Drying of an inland river’s terminal lake in arid regions is an important signal of environmental degradation in downstream regions. A long-term, high-resolution understanding of the lake’s retreat and expansion and the driving mechanisms will inform future adaptive water management strategies, ecosystem restoration, and government decision-making in the context of a growing water scarcity in the inland river basin. The shrubs that grow along the shore of a lake often provide evidence of lake retreat or expansion. The chronological results showed that the earliest germination dates of the lakeshore shrubs, tamarisk, were in 1901, 1943, 1966, 2009, and 1990 from the higher terrace to the lower terrace of East Juyan Lake, a terminal lake of China’s Heihe River. Coupled with river and lake hydrological data, six obvious lake’s fluctuations were identified: shrinkage from 1900 to 1940s and during the early 1990s, expansion and retreat in the late 1950s and early 1970s, continued expansion from 2002 to 2008, and stabilization at a water area of around 40 km2 from 2009 to the present. The water elevation in the 1900s was below 905 m a.s.l., resulting in a water area <80 km2, but decreased to 40 km2 after 1960 and dried up completely by the 1990s. By analysing climatic and hydrological records since 1950, tree-ring climate proxy data, river runoff outside the observation period, and water resource consumption in the middle and lower reaches of the Heihe River, we found that the periodic expansion and retreat of East Juyan Lake was influenced by both climate change and human activities, but especially by human activities. The lake’s recent recovery and stability was achieved by government policy designed to provide environmental flows to the lake. 相似文献
2.
Changes in rice disasters across China in recent decades and the meteorological and agronomic causes 总被引:9,自引:0,他引:9
Both climate extremes and agricultural disasters have been reported to increase in recent decades; however, so far, we have little idea on the characteristics of agricultural disasters changes, as well as their meteorological and agronomic causes. Here, using the observed records on rice disasters at agro-meteorological stations across China and the meteorological indexes, we investigated the temporal and spatial changes of major rice disasters occurrence frequency and their relationships to climate change, climate extremes and agronomic practices from 1991 to 2009. We presented the temporal and spatial changes in occurrence frequency of major rice disasters, including droughts, floods, heat stress, chilling damage, insects and diseases, during the warmer period of 2000–2009, in comparison with the period of 1991–2000, based on both the observed records and the meteorological indexes. The results showed that changes in rice disasters could be largely ascribed to changes in climate extremes in recent decades. Floods, insects and diseases occurred more frequently at earlier growth stages; in contrast, chilling damage occurred more frequently at later growth stages in southwestern China during the period of 2000–2009, in comparison with the period of 1991–2000. Our findings highlighted the options should be taken timely and scientifically to reduce the disasters and to cope with ongoing climate change, based on the characteristics of agricultural disasters changes in recent decades. 相似文献
3.
This paper focuses on the distribution of 137Cs and 210Pb(xs) in 51 estuarine and marine sediment cores collected between the Upstart Bay and Rockingham Bay in the Great Barrier Reef Lagoon, north-eastern Australia. Historical records of 210Pb(xs) and 137Cs atmospheric deposition and present day terrestrial inventories in north-eastern Australia are presented. 210Pb(xs) and 137Cs fluxes measured on suspended sediments in the Burdekin River are considered to be a source of recent inputs of these nuclides to the nearshore region of this part of the Great Barrier Reef. Direct correlations between sediment nuclide inventories, maximum detectable depths, and sediment mass accumulation rates (MARs), calculated using both 137Cs and 210Pb(xs), are explored. In relation to inventories of 210Pb(xs), 60% of atmospheric fallout 137Cs appears to be missing from the sediments. The reasons for these differences in two tracers, primarily of atmospheric origin, are discussed in terms of the geochemical properties of these two nuclides. Evidence is presented to support the hypothesis that the 137Cs distribution in these cores can be a useful independent tracer which provides confirmation of MARs calculated from the decay of 210Pb(xs). 相似文献
4.
India’s continued development depends on the availability of adequate water. This paper applies a data-driven approach to estimate the intra-annual dynamics of water stress across the central Indian Highlands over the period 2002–2012. We investigate the spatial distribution of water demanding sectors including industry, domestic, irrigation, livestock and thermal power generation. We also examine the vulnerability of urban centers within the study area to water stress. We find that 74 % of the area of the central Indian Highlands experienced water stress (defined as demand exceeding supply) for 4 or more months out of the year. The rabi (winter) season irrigation drives the intra-annual water stress across the landscape. The Godavari basin experiences the most surface water stress while the Ganga and Narmada basins experience water stress due to groundwater deficits as a result of rabi irrigation. All urban centers experience water stress at some time during a year. Urban centers in the Godavari basin are considerably water stressed, for example, Achalpur, Nagpur and Chandrapur experience water stress 8 months out of the year. Irrigation dominates water use accounting for 95 % of the total water demand, with substantial increases in irrigated land over the last decade. Managing land use to promote hydrologic functions will become increasingly important as water stress increases. 相似文献
5.
Zalewski M Karpiñska M Mnich Z Kapała J Zalewski P 《Journal of environmental radioactivity》2001,53(2):167-173
This paper presents the results of radon concentration measurements in the drinking water from the municipal water supply system and private wells located in the north-eastern part of Poland. The measurements were carried out on 643 samples using a liquid scintillation method. The mean value was found to be 5262 Bq m-3 with a maximum of 38347 Bq m-3. The samples were obtained from different water-bearing levels, i.e. surface water, deep borehole water and well water and have respective mean values of 3398, 5178 and 6155 Bq m-3. In 57 water samples, a guideline maximum level of 11,000 Bq m-3 was found to be exceeded. The observed radon concentration in water can contribute to a 2% increase in indoor radon concentration. 相似文献
6.
Analyzing the carbon dynamics of central European forests: comparison of Biome-BGC simulations with measurements 总被引:1,自引:1,他引:1
Biogeochemical models are often used for making projections of future carbon dynamics under scenarios of global change. The aim of this study was to assess the accuracy of the process-based biogeochemical model Biome-BGC for application in central European forests from the lowlands to upper treeline as a pre-requisite for environmental impact assessments. We analyzed model behavior along an altitudinal gradient across the alpine treeline, which provided insights on the sensitivity of simulated average carbon pools to changes in environmental factors. A second set of tests included medium-term (30 years) simulations of carbon fluxes, and a third set of tests focused on daily carbon and water fluxes. Model results were compared to aboveground biomass measurements, leaf area index recordings as well as net ecosystem exchange (NEE) and actual evapotranspiration (AET) measurements. The simulated medium-term forest growth agreed well with measured data. Also daily NEE fluxes were simulated adequately in most cases. Problems were detected when simulating ecosystems close to the upper timberline (overestimation of measured growth and pool sizes), and when simulating daily AET fluxes (overestimation of measured fluxes). The results showed that future applications of Biome-BGC could benefit much from an improvement of model algorithms (e.g., the Q10 model for respiration) as well as from a detailed analysis of the ecological significance of crucial parameters (e.g., the canopy water interception coefficient). 相似文献
7.
Understanding the glacier mass balance is necessary to explain the rate of shrinkage and to infer the impact of climate change. The present study provides an overview of the glacier mass balance records by glaciological, geodetic, hydrological and accumulation-area ratio (AAR) and specific mass balance relationship methods in the Indian Himalaya since 1970s. It suggests that the mass balance measurements by glaciological methods have been conducted for ten glaciers in the western Himalaya, four glaciers in the central Himalaya and one in the eastern Himalaya. Hydrological mass balance has been conducted only on Siachen Glacier from 1987 to 1991. Geodetic method has been attempted for the Lahaul–Spiti region for a short time span during 1999–2011 and Hindu Kush–Karakoram–Himalaya region from 2003 to 2008. We compared in situ specific balance data series with specific mass balance derived from AAR and specific mass balance relationship. The results derived from existing and newly presented regression model based on AAR and specific mass balance relationship induced unrealistic specific mass balance for several glaciers. We also revised AAR0 and ELA0 based on available in situ AAR and specific mass balance data series of Indian Himalayan glaciers. In general, in situ specific and cumulative specific mass balance observed over different regions of the Indian Himalayan glaciers shows mostly negative mass balance years with a few positive ones during 1974–2012. On a regional level, the geodetic studies suggest that on the whole western, the central and the eastern Himalaya experienced vast thinning during the last decade (2000s). Conversely, Karakoram region showed slight mass gain during almost similar period. However, the glaciological, hydrological and geodetic mass balance data appear to exhibit short time series bias. We therefore recommend creation of benchmark glaciers network for future research to determine the impact of climate change on the Himalayan cryosphere. 相似文献
8.
Forest fires and adaptation options in Europe 总被引:1,自引:0,他引:1
Nikolay Khabarov Andrey Krasovskii Michael Obersteiner Rob Swart Alessandro Dosio Jesús San-Miguel-Ayanz Tracy Durrant Andrea Camia Mirco Migliavacca 《Regional Environmental Change》2016,16(1):21-30
This paper presents a quantitative assessment of adaptation options in the context of forest fires in Europe under projected climate change. A standalone fire model (SFM) based on a state-of-the-art large-scale forest fire modelling algorithm is used to explore fuel removal through prescribed burnings and improved fire suppression as adaptation options. The climate change projections are provided by three climate models reflecting the SRES A2 scenario. The SFM’s modelled burned areas for selected test countries in Europe show satisfying agreement with observed data coming from two different sources (European Forest Fire Information System and Global Fire Emissions Database). Our estimation of the potential increase in burned areas in Europe under “no adaptation” scenario is about 200 % by 2090 (compared with 2000–2008). The application of prescribed burnings has the potential to keep that increase below 50 %. Improvements in fire suppression might reduce this impact even further, e.g. boosting the probability of putting out a fire within a day by 10 % would result in about a 30 % decrease in annual burned areas. By taking more adaptation options into consideration, such as using agricultural fields as fire breaks, behavioural changes, and long-term options, burned areas can be potentially reduced further than projected in our analysis. 相似文献
9.
N. Dolgener L. Freudenberger N. Schneeweiss P. L. Ibisch R. Tiedemann 《Regional Environmental Change》2014,14(3):1063-1072
Environmental change is likely to have a strong impact on biodiversity, and many species may shift their distribution in response. In this study, we aimed at projecting the availability of suitable habitat for an endangered amphibian species, the Fire-bellied toad Bombina bombina, in Brandenburg (north-eastern Germany). We modelled a potential habitat distribution map based on (1) a database with 10,581 presence records for Bombina from the years 1990 to 2009, (2) current estimates for ecogeographical variables (EGVs) and (3) the future projection of these EGVs according to the statistical regional model, respectively, the soil and water integrated model, applying the maximum entropy approach (Maxent). By comparing current and potential future distributions, we evaluated the projected change in distribution of suitable habitats and identified the environmental variables most associated with habitat suitability that turned out to be climatic variables related to the hydrological cycle. Under the applied scenario, our results indicate increasing habitat suitability in many areas and an extended range of suitable habitats. However, even if the environmental conditions in Brandenburg may change as predicted, it is questionable whether the Fire-bellied toad will truly benefit, as dispersal abilities of amphibian species are limited and strongly influenced by anthropogenic disturbances, that is, intensive agriculture, habitat destruction and fragmentation. Furthermore, agronomic pressure is likely to increase on productive areas with fertile soils and high water retention capacities, indeed those areas suitable for B. bombina. All these changes may affect temporary pond hydrology as well as the reproductive success and breeding phenology of toads. 相似文献
10.
The purpose of this study is merely to review the current situation in the designing and implementation of the emission trading programs in Europe. Historical data show that although there is a series of shortcomings in their current functioning, employing such instruments for GHG reduction policy making is strongly expected to be efficient and effective. The European Union Emission Trading Scheme (EU ETS), Clean Development Mechanism (CDM) and Joint Implementation (JI) are just a few examples of the ambitious EU initiative that heavily relies on such instruments. We dwell on their operations and achievements by far and all the content in this article is expected to convince the Chinese government and regional public authorities to take positive actions and attitudes in promoting these instruments. 相似文献
11.
This paper presents a screening tool for the location-specific prioritization of human pharmaceutical emissions in Europe, based on risk quotients for the aquatic environment and human health. The tool provides direction towards either monitoring activities or additional research. Its application is illustrated for a set of 11 human antibiotics and 7 antineoplastics. Risk quotients for the aquatic environment were highest for levofloxacin, doxycycline and ciprofloxacin, located in Northern Italy (Milan region; particularly levofloxacin) and other densely populated areas in Europe (e.g. London, Krakow and the Ruhr area). Risk quotients for human health not only depend on pharmaceutical and location, but also on behavioral characteristics, such as consumption patterns. Infants in eastern Spain that consume locally produced food and conventionally treated drinking water were predicted to run the highest risks. A limited comparison with measured concentrations in surface water showed that predicted and measured concentrations are approximately within one order of magnitude. 相似文献
12.
P. P. Popov 《Russian Journal of Ecology》2003,34(1):27-33
The structures and differentiation patterns of the Norway spruce (Picea abies) and Siberian spruce (P. obovata) populations have been studied in a wide area, including the transition zone of their continuous geographic range. The areas occupied by transitional populations have been detected. Series of distinct populations of the Norway and Siberian spruces are located to the west and east of them, respectively. 相似文献
13.
The structure of the ichthyofauna in water bodies of Kaluga oblast has undergone significant rearrangements over the past
20 years. The abundance of some species has increased, while that of other species has decreased; spontaneous dispersal of
some fishes is underway. Synchronous fluctuations of fish abundance (“waves of life”) take place simultaneously in the Western
Dvina, Dnieper, and Volga basins. These processes differ in intensity depending on fish species and are conditioned by a number
of factors, including changes in hydrological regimes of rivers, improvement of the ecological state of small rivers, and
increased poaching pressure. The results of monitoring the ichthyofauna fauna of small rivers are used as an example to trace
the routes of fish dispersal and discuss changes in the composition of fish communities. 相似文献
14.
了解和认识百年来中国气候发生的变化、引起其变化的驱动因素以及未来的可能变化,可以更好地适应和减缓气候变化。本文综合评估了观测到的中国气候变化事实、中国气候变化的驱动力、中国未来气候变化预估三大方面,分析了气候变暖的趋势、水循环以及降水和冰川变化、极端天气气候事件变化、生物化学循环、海洋和土地覆盖变化及其气候效应以及未来气候变化的特点和趋势等最新科学进展。在中国百年温度趋势、气候系统多气候指标变化特征、极端天气气候事件中的人类活动作用以及气候系统模拟能力等方面的研究有了新的进展。可以看到中国气候变暖趋势持续、大气二氧化碳等长寿命温室气体浓度继续增长、人为强迫影响了多种气候要素在强度和频率的变化,中国陆地生态系统的固碳量增加。本文最后提出未来中国气候变化研究需要进一步加强的问题,包括:中国气候变化中的城市化效应、气候系统内部变率在年代际变化中的作用、气溶胶-云-降雨相互作用的机理、大范围土地利用变化(如大规模生态恢复工程)的气候效应,以及云辐射反馈、海洋环流对气候变化的响应与反馈、气候-碳循环反馈等过程对气候模拟不确定的影响等。 相似文献
15.
Human activities are projected to lead to substantial increases in temperature that will impact northern Europe during winter and southern Europe during summer. Moreover, it is expected that these changes will cause increasing water shortages along the Mediterranean and in the south-west Balkans and in the south of European Russia. The consequences on the European agricultural ecosystems are likely to vary widely depending on the cropping system being investigated (i.e. cereals vs. forage crops vs. perennial horticulture), the region and the likely climate changes. In northern Europe, increases in yield and expansion of climatically suitable areas are expected to dominate, whereas disadvantages from increases in water shortage and extreme weather events (heat, drought, storms) will dominate in southern Europe. These effects may reinforce the current trends of intensification of agriculture in northern and western Europe and extensification and abandonment in the Mediterranean and south-eastern parts of Europe. Among the adaptation options (i.e. autonomous or planned adaptation strategies) that may be explored to minimize the negative impacts of climate changes and to take advantage of positive impacts, changes in crop species, cultivar, sowing date, fertilization, irrigation, drainage, land allocation and farming system seem to be the most appropriate. In adopting these options, however, it is necessary to consider the multifunctional role of agriculture and to strike a variable balance between economic, environmental and economic functions in different European regions. 相似文献
16.
Olaf Jonkeren Piet Rietveld Jos van Ommeren Aline te Linde 《Regional Environmental Change》2014,14(3):953-965
Future climate conditions are likely to affect inland waterway transport in Europe. According to some climate scenarios, in summer, in the river Rhine, periods with low water levels are likely to occur more often and become more serious. Then inland waterway transport carriers will experience more severe restrictions on the load factor of their inland ships, which implies a stronger reduction in transport capacity in the market. Transport prices will rise under such conditions. Some studies reviewed in this paper find that at extremely low water levels, the price per tonne for inland waterway transport in the river Rhine area will almost double. These increased transport prices result in welfare losses. For the dry summer in 2003, the losses for North West Europe are estimated to sum up to around €480 million. Increased transport prices trigger adaptation. Inland waterway carriers may use smaller vessels, and shippers have the opportunity to shift from inland waterway transport to alternative transport modes in periods with low water levels. This effect is probably rather modest, however, with a modal shift to road and rail smaller than 10 %. Also, changes in transport costs may lead to relocation of certain economic activities in the long run. 相似文献
17.
Tamara Metze 《Environmental Communication: A Journal of Nature and Culture》2016,10(3):365-379
ABSTRACTHydraulic fracturing for shale gas is a controversial issue in most countries. In these controversies, actors use discursive boundary work to convince various audiences of their position. Discursive boundary work is a communicative strategy that involves the framing of facts in contrast to other kinds of arguments. In this article we develop the Dynamic Discourse Coalition (DDC) approach to study how discourse coalitions deploy discursive boundary work to confirm, integrate, polarize or disintegrate their own and opposing discourse coalitions. The DDC approach enables a deeper understanding of the dynamics of controversies about hydraulic fracturing and similar contested technologies by illuminating the influence of communicative processes on policy formation. Based on an analysis of policy documents, academic reports, newspapers, interviews and websites we compare the dynamics of contesting discourse coalitions in the Netherlands and New York. This analysis explains why policy formed in different ways in the cases, despite the apparent similarity of the discourse coalitions that emerged in the respective controversies. 相似文献
18.
Geochemical specialization of the soil and plant cover has been revealed in the vicinity of the active Karymsky volcano (the eastern coast of the Kamchatka Peninsula), where the concentrations of most trace elements in the soil are lower than their clarkes but those in plants exceed their contents commonly recorded in living matter. Freshly deposited volcanic ash is enriched with movable forms of trace elements. As a result of hypergenic processes, they are dissolved and transferred to ground and surface waters, which accounts for a rich mineral composition of vegetation. 相似文献
19.
Towards a spatially explicit and quantitative vulnerability assessment of environmental change in Europe 总被引:5,自引:4,他引:5
Over the next century, society will increasingly be confronted with the impacts of global change (e.g. pollution, land use changes, and climate change). Multiple scenarios provide us with a range of possible changes in socio-economic trends, land uses and climate (i.e. exposure) and allow us to assess the response of ecosystems and changes in the services they provide (i.e. potential impacts). Since vulnerability to global change is less when society is able to adapt, it is important to provide decision makers with tools that will allow them to assess and compare the vulnerability of different sectors and regions to global change, taking into account exposure and sensitivity, as well as adaptive capacity. This paper presents a method that allows quantitative spatial analyses of the vulnerability of the human-environment system on a European scale. It is a first step towards providing stakeholders and policy makers with a spatially explicit portfolio of comparable projections of ecosystem services, providing a basis for discussion on the sustainable management of Europe’s natural resources.
相似文献
Marc J. MetzgerEmail: Phone: +31-317-482983Fax: +31-317-484839 |
20.
A spatially explicit and quantitative vulnerability assessment of ecosystem service change in Europe 总被引:4,自引:1,他引:4
Marc J. Metzger Dagmar Schröter Rik Leemans Wolfgang Cramer 《Regional Environmental Change》2008,8(3):91-107
Environmental change alters ecosystem functioning and may put the provision of services to human at risk. This paper presents
a spatially explicit and quantitative assessment of the corresponding vulnerability for Europe, using a new framework designed
to answer multidisciplinary policy relevant questions about the vulnerability of the human-environment system to global change.
Scenarios were constructed for a range of possible changes in socio-economic trends, land uses and climate. These scenarios
were used as inputs in a range of ecosystem models in order to assess the response of ecosystem function as well as the changes
in the services they provide. The framework was used to relate the impacts of changing ecosystem service provision for four
sectors in relation to each other, and to combine them with a simple, but generic index for societal adaptive capacity. By
allowing analysis of different sectors, regions and development pathways, the vulnerability assessment provides a basis for
discussion between stakeholders and policymakers about sustainable management of Europe’s natural resources.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
相似文献
Marc J. MetzgerEmail: |