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61.
The composition and structure of tree stands near the timberline have been studied on different slopes and at different elevations
in the Tylaisko-Konzhakovsko-Serebryanskii Massif, the North Urals. It has been found that the upper limits of tree stands
with different degrees of canopy closure have risen considerably (by about 100 m of elevation) since the mid-19th century,
although the formation of these stands started as early as the late 18th century. Woodless areas in the eastern part of the
massif started to be colonized by Larix sibirica in the late 18th to early 19th centuries; those in the western part, by Picea obovata in the mid-19th century; and in the southern part, by Betula tortuosa in the late 19th century. Analysis of meteorological data provides evidence for warming and increasing humidity of the climate
since the late 19th century. Favorable climatic changes that facilitated the expansion of the forest have taken place both
in the summer (prolongation of the growing period) and in winter seasons (increase of air temperature and precipitation).
The observed differences in the composition and dynamics of tree stands between the studied areas of the mountain range are
most probably explained by different requirements of tree species for the depth of snow cover and the degree of soil freezing. 相似文献
62.
Konstantinos C. Makris Dibyendu Sarkar Jason Salazar Pravin Punamiya Rupali Datta 《Environmental science and pollution research international》2010,17(1):195-202
Background, aim, and scope
Alum (aluminum sulfate) is the currently preferred chemical amendment for phosphorus (P) treatment in poultry litter (PL). Aluminum-based drinking-water treatment residuals (Al-WTRs) are the waste by-product of the drinking-water treatment process and have been effectively used to remove P from aqueous solutions, but their effectiveness in PL water extracts has not been studied in detail. Elevated cost associated with alum could be minimized by using the equally effective WTRs to remove soluble P from PL, and they can be obtained at a minimal cost from drinking-water treatment plants. 相似文献63.
International environmental agreements (IEAs) can coordinate abatement of transboundary pollutants. This paper investigates
how heterogeneous countries facing a stock pollutant might structure such an agreement. In particular, we examine how an IEA
might be implemented with a set of monetary transfers. The focus is on transfers that are time invariant, linear in emissions,
and consistent with budget balance. There is a range of such schemes that would induce efficient emissions. We provide a simple
and intuitive characterization of these penalties and describe how specific proposals might be chosen in order to facilitate
compliance and implementation. Our proposals are illustrated with a simple example. We show that heterogeneity reduces the
scope for penalty schemes to jointly satisfy desirable properties. 相似文献
64.
65.
The Role of Disaggregation of Asset Values in Flood Loss Estimation: A Comparison of Different Modeling Approaches at the Mulde River,Germany 总被引:3,自引:0,他引:3
Anja Wünsch Ulrich Herrmann Heidi Kreibich Annegret H. Thieken 《Environmental management》2009,44(3):524-541
In loss estimation there is a spatial mismatch of hazard data that are commonly modeled on an explicit raster level and exposure
data that are often available only for aggregated administrative units. Usually disaggregation methods that use ancillary
information to distribute lumped exposure data in a finer spatial resolution help to bridge this gap. However, the actual
influence of different mapping techniques and ancillary data on the final loss estimation has not been analyzed yet. In this
paper three methods are applied to disaggregate residential building assets using two kinds of land use/land cover (LULC)
data. The resulting disaggregated assets are validated and compared using census data of the residential building number on
the community and constituency level. In addition, the disaggregated assets are taken to estimate residential building losses
due to the flood in August 2002 in 21 municipalities on the River Mulde in Saxony, Germany. Losses are calculated with the
help of four loss models. In general, disaggregation helps to decrease the error variance within the loss estimation. It must,
however, be stated that the application of sophisticated disaggregation methods does not lead to significant improvements
compared to the straightforward binary method. Therefore more effort should instead be put into the provision of high-resolution
LULC data. Finally, the remaining uncertainties in loss estimation are high and demand further improvements in all modeling
aspects. 相似文献
66.
Adaptive maritime spatial planning (MSP) uses monitoring and evaluation of the effectiveness of spatial and temporal management
measures to promote understanding and improve planning and decision-making. An adaptive approach to MSP involves exploring
alternative ways to meet management objectives, predicting the outcomes of alternative management measures, implementing one
or more of these alternative management measures, monitoring to learn about the effects of management measures, and then using
the results to update knowledge and adjust management actions. A monitoring and evaluation plan should be designed to be both
cost effective and comprehensive. The process of setting and assessing performance metrics requires that the ecological and
socio-economic objectives of the spatial management plan must be clearly stated up front for management actions to reflect
those objectives accurately. To evaluate the effectiveness of a MSP plan, a range of ecological, socio-economic and institutional
indicators need to be developed and monitored. 相似文献
67.
68.
Jagmohan Sharma Sujata Upgupta Rajesh Kumar Rajiv Kumar Chaturvedi G. Bala N H Ravindranath 《Mitigation and Adaptation Strategies for Global Change》2017,22(1):29-44
Assessment of vulnerability is an important step in building long-term resilience in the forestry sector. The objective of this paper is to present a methodological approach to assess inherent vulnerability of forests at landscape level. The approach involves use of vulnerability indicators, the pairwise comparison method, and geographic information system (GIS) tools. We apply this approach to assess the inherent vulnerability of forests of the Western Ghats Karnataka (WGK) landscape, which is a part of the Western Ghats biodiversity hotspot in India. Four vulnerability indicators, namely biological richness, disturbance index, canopy cover, and slope, are selected. We find that forests in 30, 36, 19, and 15 % grid points in this region show low, medium, high, and very high inherent vulnerability, respectively. The forest showing high and very high inherent vulnerability are mostly dry deciduous forests and plantations located largely on the eastern side of the landscape. We also find that canopy cover is one of the key indicators that determine the inherent vulnerability of forests, and natural forests are inherently less vulnerable than man-made plantations. Spatial assessment of inherent vulnerability of forests at landscape level is particularly useful for developing strategies to build resilience to current stressors and climate change in future. 相似文献
69.
Vulnerability of agro-ecological zones in India under the earth system climate model scenarios 总被引:1,自引:0,他引:1
Roopam Shukla Anusheema Chakraborty P. K. Joshi 《Mitigation and Adaptation Strategies for Global Change》2017,22(3):399-425
India being a developing economy dependent on climate-sensitive sector like agriculture is highly vulnerable to impacts of global climate change. Vulnerability to climate change, however, differs spatially within the country owing to regional differences in exposure, sensitivity, and adaptive capacity. The study uses the Hadley Centre Global Environment Model version 2-Earth System (HadGEM-ES) climate projections to assess the dynamics in vulnerability across four climate change exposure scenarios developed using Representative Concentration Pathways (RCPs). The analysis was carried out at subnational (district) level; the results were interpreted and reported for their corresponding agro-ecological zones. Vulnerability of each district was quantified using indicators capturing climatic variability, ecological and demographic sensitivity, and socio-economic capacity. Our analysis further assigns probabilities to vulnerability classes of all the 579 districts falling under different agro-ecological zones. The results of the vulnerability profile show that Western plains, Northern plains, and central highlands of the arid and semi-arid agro-ecological zones are the most vulnerable regions in the current scenario (1950–2000). In the future scenario (2050), it extends along districts falling within Deccan plateau and Central (Malwa) highlands, lying in the arid and semi-arid zones, along with regions vulnerable in the current scenario, recording the highest vulnerability score across all exposure scenarios. These regions exhibit highest degree of variation in climatic parameters, ecological fragility, socio-economic marginality, and limited accessibility to resources, generating conditions of high vulnerability. The study emphasizes on the priority to take up adaptive management actions in the identified vulnerable districts to not only reduce risks of climate change, but also enhance their inherent capacity to withstand any future changes in climate. It provides a systematic approach to explicitly identify vulnerable regions, where regional planners and policy makers can build on existing adaptation decision-making by utilizing an interdisciplinary approach in the context of global change scenario. 相似文献