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11.
Deltas, as macro and micro biological systems at high productive levels, are the natural reserve areas of the world. Those in Turkey present the international importance landscapes as to the various ecosystem characteristics and land use patterns. Nevertheless, these areas are currently facing many problems such as biodiversity loss and environmental degradation owing to coastal settlements and pollution factors. This paper describes the factors responsible for the main features and degradation types of the Deltaic landscapes and their impact for future land use. It also deals with : an overview of the Kizilirmak Delta, one of the most important Deltas along the central part of Black Sea Region (Turkey); presents major ecosystem of it; identifies land use pattern and discusses the threats by environmental and human induced disturbances. The most considering feature of this Delta is to show the largest and most significant wetland area of Turkey which has been able to protect its natural beauties on the Black Sea Coasts. A Delta plain of 56000 hectares extends through the area at the north of the Samsun-Sinop highway. The ecological system of the Delta is extremely rich in terms of its biological variety as well as its fauna (especially number of bird species). But, the Delta including terrestrial areas close to the water resources and the vegetation between aquatic and terrestrial systems, has been constantly modified by human activities. Consequently, some considerations for environmental conservation and sustainable management were put forward for the future generations.  相似文献   
12.
The De?irmendere and Galyan (De?irmendere tributary) Rivers that discharge their water into the Black Sea are important watersheds in the northeastern part of Turkey. Water quality parameters were sampled from 1997 through 2001 for each year at five sites (three for Galyan, two for Degirmendere) along 29 and 42 km gradients, respectively covering all seasons. Surface water was collected from the sites and analyzed for temperature, total alkaline (MAAL), total dissolved solids (TDS), dissolved oxygen (DO), pH, conductivity (EC), nitrate (NO3), nitrite (NO2), total hardness (TH), phenolphthalein alkalinities (PAL) and organic matter (PV). Seasonal changes of water quality were analyzed statistically for both Rivers and evaluated according to the TS 266, EU and WHO standards. The analysis of variance results showed that Ca, Mg, MAL, NO3, pH, TDS and TH parameters of the De?irmendere River and Ca, DO, EC, MAL, NO3, pH and TH parameters of the Galyan River showed seasonal differences (p<0.05). The maximum values of the water pollution parameters for the two Rivers were below the threshold values throughout the study period. When both Rivers were compared, the mean values of the pollution parameters of the Degirmendere River were higher than those of the Galyan River and very close the limits. The results indicate that both Rivers can be used for the production of potable water during all seasons but only with an advanced treatment in the De?irmendere and a moderate treatment in the Galyan River, and for indirect and non-contact recreational activities.  相似文献   
13.
Forest management today has to meet a number of objectives. Planning of multi-functional forest road networks is one essential for meeting the aims of the sustainable forest concept. Road construction damages the natural environment unless it is carefully thought out. As forest engineers we have to consider the protection of nature when designing forest roads. With this aim in mind, a new network planning approach was developed for wood-harvesting. A geographical information system (GIS) was used to evaluate the data and planning process. The new forest road network plan for Catak Forest District constituted the addition of a new 16-road segment, total length 59.067 km, to the existing road network plan, for the purpose of wood-harvesting operations. Forest road density value was determined as 22.8 m/ha: the opening-up rate of the area was increased to 77.8% and the opening-up rate of the existing stand value was increased to 94.3% after close examination. 90.2% of roads were planned for the forest areas where there is likely to be minimal negative environmental impact.  相似文献   
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