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51.
The eastern Mediterranean region has been subjected to intensive human disturbance in the past 10,000 years, mainly in the forms of agro-pastoral activities such as grazing, shrub clearing, and prescribed burning. This disturbance history resulted in the formation of highly heterogeneous landscapes, characterized by high biodiversity. Recent changes in human activities have resulted in a decrease of landscape heterogeneity, leading to decreasing biodiversity and increasing fire risk. To conserve heterogeneity, land managers apply disturbance based management practices, using the same activities that created and maintained landscape heterogeneity in the past. However, the long-term and large-scale outcomes of these disturbances are often unknown, due to the complex response of Mediterranean vegetation to disturbance. Here we report on a spatially explicit, hybrid, and spatially hierarchical ecological model developed by us. The model attempts to predict the outcome of various disturbance based management activities on the long-term spatio-temporal dynamics of five common Mediterranean vegetation types. The model uses a spatially explicit state and transition formulation, with continuous transition functions. Model simulations were conducted on a Mediterranean landscape in Northern Israel, incorporating various disturbance practices that are common in the region. Simulation results highlight the potential of disturbance based management as a tool for conserving landscape heterogeneity, as well as the complex interactions between disturbances and the spatial structure of the landscape in Mediterranean regions.  相似文献   
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Mobile coastal dunes are of significant ecological importance both globally and locally. Yet a large portion of these dunes are disappearing due to encroachment of local shrubs and exotic plants, resulting in changes of floristic and faunal composition, and an overall decrease in biodiversity of coastal systems. Active management is therefore required to maintain mobile dune presence. This study focuses on economic valuation of coastal dunes in Israel, based on public and professional ecological perspectives. This comparison allows reflection on the suitability of a contingent valuation method (CVM) to assess ecological restoration and conservation projects. The CVM was applied in Nizzanim LTER nature reserve in Israel, and concurrently, data of plant species composition on stabilized and mobile dunes were used to calculate the ecological value index (EVI) of the different dune states. The EVI was then transformed into monetary terms by combining the public valuation and the relative proportion of the various species to the total coverage. The monetary values derived from the general public and the ecological assessment were then compared and used to estimate the expected change in economic value resulting from a state shift from mobile to stabilized dunes. According to the CVM, the total value of the Nizzanim coastal dunes would drop from 344 to 197 million Israeli Shekels (NIS) (1 Shekel = $0.39) if active management does not take place, a reduction of 42 % in value. However, results from the EVI indicate only a 33 % decrease in ecological value (in monetary terms) in the absence of active management. We suggest that in this case, general public perception is strong enough to justify conservation decisions, even though they are not professional ecologists. However, we still recommend the use of both measures for land use decision making.  相似文献   
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Projected climate change over Turkey has been analyzed by using the reference (1961–1990) and future (2071–2100) climate simulations produced by ICTP-RegCM3. Since examining Turkey as a single region could be misleading due to the existence of complex topography and different climatic regions, Turkey has been separated into seven climatic regions to evaluate the surface temperature and precipitation changes. Comparison of the reference simulation with observations was made spatially by using a monthly gridded data set and area-averaged surface data compiled from 114 meteorological stations for each climatic region of Turkey. In the future simulation, warming over Turkey’s climatic regions is in the range of 2–5 °C. Summer warming over western regions of Turkey is 3 °C higher than the winter warming. During winter, in the future simulation, precipitation decreases very significantly over southeastern Turkey (24 %), which covers most of the upstream of Euphrates and Tigris river basin. This projected decrease could be a major source of concern for Turkey and the neighboring countries. Our results indicate that a significant increase (48 %) in the autumn season precipitation is simulated over southeastern Turkey, which may help to offset the winter deficit and therefore reduce the net change during the annual cycle.  相似文献   
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Environmental Science and Pollution Research - In this study, thermogravimetric analysis (TGA) was performed under the air environment for four different heating rates (10, 20, 30, and 40 °C...  相似文献   
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Environmental Science and Pollution Research - Developing land suitability models for strategically critical agricultural products to expand sustainable agricultural policies and sensitive...  相似文献   
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