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101.
A field plot experiment was conducted in the Palestinian Autonomous Areas to study the effect of stonewalled terracing on soil and water conservation as compared to the nonterraced areas. Effects of the wheat canopy were considered as a second treatment. The experiment was undertaken over a period of two seasons (2000 and 2001). The results of the experiment found that the mean soil erosion was significantly lower (P < 0.05) in the terraced plots than in those that were nonterraced (182 kg/ha and 3525 kg/ha during the first season, 1769 kg/ha and 5057 kg/ha during the second season for terraced and nonterraced plots, respectively). A similar trend was observed with respect to runoff in areas under the same treatments. The wheat canopy showed lower, but not significant runoff and erosion in most of the cases for both seasons. Due to better soil and water conservation, the terraced plots obtained significantly higher total plant dry matter than nonterraced plots (1570 and 630 kg/ha in 2000, 2545 and 889 kg/ha in 2001 for terraced and nonterraced treatment, respectively). The runoff coefficient was 20% and 4% for the nonterraced and terraced plots, respectively. Rainstorms with intensity ≥4 mm/hand rainfall ≥10 mm are more likely to cause runoff and erosion.  相似文献   
102.
In order to reconcile the need for conserving and improving neglected Mediterranean upland ecosystems with socio-economic advancement, new concepts of integrated landscape management are required. For this purpose a mode of a closely interwoven network of multiple land-use patterns is suggested, based on vegetation management and manipulation of the soil-plant-animal complex and on multi-purpose environmental landscaping and afforestation. The latter is essential for revegetation of denuded slopes and for fire protection and buffer zones, and is aimed at the creation of semi-natural, multi-layered forests, parks and woodlands. From these, highest overall multiple use benefits can be expected for environmental and watershed protection, resistance to fire hazard, biotic diversity and wildlife, recreation amenity., and plant and animal production.For optimization and dynamic land-use planning such relative values of multiple use benefits should be expressed in quantitative data and applied in dynamic planning of multiple use strategies, which could be tested first in combined research and demonstration schemes.  相似文献   
103.
Predicting the multiple pathways of plant succession   总被引:4,自引:0,他引:4  
Classical concepts view succession as a deterministic, mechanistic regeneration of the disturbed community, and thus have limited applicability to fire-prone ecosystems, A recently developed multiple pathway succession model appears to have more realism and applicability in frequently disturbed ecosystems. It includes a set of species-specific attributes that are vital to reproduction and survival, and permits variable succession pathways depending on the stand's age (and thus species composition) when disturbed. Examples from Australia and the northern Rocky Mountains (USA) are presented, as are approaches to refining and improving the model.  相似文献   
104.
Sustainable Management for the Eastern Mediterranean Coast of Turkey   总被引:2,自引:0,他引:2  
The objective of this article is to propose a program for the integrated coastal zone management that is required to stimulate and guide sustainable development of the Mediterranean coastal zone of Turkey. Improved data collection, quality control, analysis, and data management will provide a firm basis for future scientific understanding of the East Mediterranean coast of Turkey and will support long-term management. Various innovative procedures were proposed for a promising ecosystem-based approach to manage coastal wetlands in the Mediterranean: remote data acquisition with new technologies; environmental quality monitoring program that will provide a baseline for monitoring; linking a Geographic Information System (GIS) with natural resource management decision routines in the context of operational wetlands, fisheries, tourism management system; environmental sensitivity analysis to ensure that permitted developments are environmentally sustainable; and use of natural species to restore the wetlands and coastal dunes and sustain the system processes. The proposed management scheme will benefit the scientific community in the Mediterranean and the management/planning community in Eastern Turkey.  相似文献   
105.
The Convention on Biological Diversity set conservation of biodiversity on the world agenda. Gaps in knowledge need to be addressed for actions to be effective and sustainable. Gaps include: species diversity, micro-organisms and their ecological roles, ecological and geographical status of species, human capacity to assess and forecast bio-ecological degradation. Requirements for global inventories call for worldwide collaboration. Criteria for setting priorities need to be formulated and agreed.Biodiversity in an eco-geographical region, the southern Mediterranean, is discussed as a case study. Outlines of national actions to contribute to world endeavor are outlined.  相似文献   
106.
Sustainable development in the Mediterranean region   总被引:1,自引:0,他引:1  
Considering its specific economic, social, environmental and political features, the status and evolution of the Mediterranean have always been of great interest to its countries and concerned partners. From the protection of the sea against pollution, the interest was progressively expanded to land based development and its impacts on environment, to coastal management and finally to sustainable development with the establishment of the Mediterranean Commission on Sustainable Development (MCSD). Cumulated knowledge, coupled with political support and commitment to a common vision, has prepared the ground for the preparation of a regional strategy for sustainable development. Its preparatory process, coordinated by the MCSD Secretariat, has been very interactive, involving various stakeholders. The strategy, adopted in 2005, has raised awareness and induced the preparation of national sustainable development strategies.  相似文献   
107.
Irrigation effects on biodiversity are poorly known, particularly in Mediterranean agro-ecosystems. In this study we analyzed irrigation effects on butterfly species richness, abundance and diversity as well as on species composition in a farmed landscape under Mediterranean climate. The study area consisted of four contiguous agricultural sub-areas with a decreasing degree of intensification: irrigated, mixed (dry and irrigated), dry and environmentally protected (i.e. Special Protection Area, SPA) dry farmland. Forty one km-transects (ten per sub-area) were searched for butterflies in 2008 and 2009. Contrary to expectations, species richness (alfa, beta and gamma diversity) was highest in both years in the most intensified sub-area (i.e. irrigated) followed by SPA, dry and mixed sub-areas. Landscape characteristics accounted for most of the between-subareas differences in species richness. Species richness was negatively related to mean field size at the landscape level and positively related to the number of trees and large shrubs along transects. Therefore, the higher number of butterfly species recorded in the irrigated farmland could be due to a more complex landscape. In contrast, butterfly abundance was highest in cereal steppes (i.e. dry and SPA sub-areas), with abundance being negatively affected by mean field size. Inter-annual change in butterfly abundance was much sharper in rainfed (i.e. dry and SPA) than in irrigated (i.e. irrigated and mixed) sub-areas. Irrigated farmland may provide more favorable conditions for butterflies by buffering the (year-to-year and summer) drought periods characterising Mediterranean climate. Species composition differed among sub-areas, with differences being partly explained by field size and number of trees and shrubs along transects. Our study suggest an important role of landscape characteristics in boosting butterfly biodiversity in intensively managed irrigated croplands and emphasizes the importance of encouraging studies on farmland butterfly diversity in different (bioclimatic) regions allowing the design of region-specific agri-environmental schemes.  相似文献   
108.
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   
109.
A stage structured population (SSP) model based on Fennel's [Fennel, W., 2001. Modelling copepods with links to circulation models. Journal of Plankton Research, 23, 1217–1232] equations is applied to Centropages typicus (Kröyer), a dominant copepod species of the North Western Mediterranean Sea (NWMS) and a prey of small pelagic fish. The model considers five groups of stages and development rates are represented by a mechanistic formulation depending on individual specific growth in each stage. Individual growth is calculated from the individual energy budget depending on food availability and temperature.  相似文献   
110.
The simultaneous accounting of effects of natural and anthropogenic changes within a common framework calls for the development of new comprehensive tools capable of integrating biological processes that span a huge range of scales, from viruses to fishes, in addition to their interactions with physical–chemical environmental properties, i.e. End-to-End models.  相似文献   
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