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171.
The article describes different steps and methodologies to create an alternative greenway with recreational, scenic, historical and cultural values in Hamsiköy-Zigana, part of Trabzon-Gümü?hane former state highway. As a first step, inventory studies and analyses were carried out to determine the cultural and natural values of the area. As the second step, area analyses studies were carried out. Depending on results of expert-based visual assessment and suitability analyses for determining the suitability of greenway planning in the study area; recreational, scenic, historical–cultural and multifunctional status of the greenway having all these three functions at the same time were mapped using suitability rank in GIS and the plan square technique. As a result, the plan squares having high suitability for the above functions were dense in the determined study, in terms of old highway and neighbourhood. In the whole area (4385.25 ha), 598.00 ha were ranked as good (A), 770.27 ha as medium (B) and 3016.98 ha as poor (C), in terms of suitability value. Seasonal assessments for recreation and scenery functions of A, B and C indicate that the area has opportunities for all seasons. As a third step, the results are discussed and some proposals suggested.  相似文献   
172.
Regional land-use development projects are undertaken to protect water resources necessary for agriculture, energy and sustaining human life. The De?irmendere valley, in the province of Trabzon in the Black Sea region of Turkey, provides clean water to the city of Trabzon. The valley is part of the Silk Road from Asia to the Black Sea and contains historical monasteries such as Sumela, Kustul and Vazelon. However, over the years, misuse of the valley has caused freshwater, sea and environmental pollution. In an attempt to overcome these problems, a multilateral project, De?irmendere Vadisi Çevre Düzenlemesi (DEVAÇED), was launched in the region. This paper aims to provide information necessary for engineering projects within the region. Six villages, on both sides of the valley, were selected for this research and evaluated in terms of river basin utilization, topography, cadastral survey of property and ownership, and land readjustment improvements. The study found illegal and improper urbanization, including industrial facilities within the valley causing water pollution. Current cadastral base maps are not sufficiently accurate for engineering projects, and in some places buildings have been constructed on unstable soils that are susceptible to landslides. The research results have helped to generate important recommendations for rehabilitation of the river basin.  相似文献   
173.
The major and trace element component of 48 recent sediment samples in three distinct intervals (0–10, 10–20, and 20–30 cm) from Lake Ac?göl is described to present the current contamination levels and grift structure of detrital and evaporate mineral patterns of these sediments in this extreme saline environment. The spatial and vertical concentrations of major oxides were not uniform in the each subsurface interval. However, similar spatial distribution patterns were observed for some major element couples, due mainly to the detrital and evaporate origin of these elements. A sequential extraction procedure including five distinct steps was also performed to determine the different bonds of trace elements in the <?60-μ particulate size of recent sediments. Eleven trace elements (Ni, Fe, Cd, Pb, Cu, Zn, As, Co, Cr, Al and Mn) in nine surface and subsurface sediment samples were analyzed with chemical partitioning procedures to determine the trace element percentage loads in these different sequential extraction phases. The obtained accuracy values via comparison of the bulk trace metal loads with the total loads of five extraction steps were satisfying for the Ni, Fe, Cd, Zn, and Co. While, bulk analysis results of the Cu, Ni, and V elements have good correlation with total organic matter, organic fraction of sequential extraction characterized by Cu, As, Cd, and Pb. Shallow Lake Ac?göl sediment is characteristic with two different redox layer a) oxic upper level sediments, where trace metals are mobilized, b) reduced subsurface level, where the trace metals are precipitated.  相似文献   
174.
A simple and sensitive solid phase extraction (SPE) method on multiwalled carbon nanotubes (MWCNTs) is presented for the determination of cadmium, lead, nickel, copper, and zinc at trace levels combined with flame atomic absorption spectrometry. The effects of parameters like pH, sample volume, sample and eluent flow rates, eluent concentration, and volume and type of eluent on the recovery of trace elements was examined. The metals retained on the nanotube at pH 6.5 as α-benzoin oxime complexes were eluted by 10 mL 2 M HNO3 in acetone. The influence of matrix ions on the developed method was also evaluated. The preconcentration factor of the method was found to be 50. The detection limits for Cd(II), Pb(II), Ni(II), Cu(II), and Zn(II) were found as 1.7, 5.5, 6.0, 2.3, and 2.4 μg L?1, respectively. To test the accuracy of the method, the method was applied to TMDA-70 fortified lake water and Spinach 1570A standard reference materials. Addition recovery studies were applied to tap water and cracked wheat samples, and determination of the analyte elements was carried out in some food samples with good results.  相似文献   
175.
There is an increasingly need to assess the contaminant levels in fish as indicators of the health and well-being of both the fish and their consumers, including humans. Fish samples were collected through the coastal waters of Turkey and the contents of cadmium, copper, chrome, copper, iron, manganese, nickel, zinc and lead in the liver and muscle tissues were determined by ICP-AES. The highest levels of each metal were found in the liver and this was followed by the muscle in both species. Among the metals analyzed, Cu, Zn and Fe were the most abundant in the different tissues while Cd and Pb were the least abundant both in Mullus barbatus (red mullet) and Merlangius merlangus (whiting). Regional changes in metal (Cd, Cu, Pb, Fe and Zn) concentration were observed in the tissues of both species, but these variations may not influence consumption advisories.  相似文献   
176.
Today, as a result of erratic and unplanned urbanization, towns are rapidly becoming a mass of concrete and town-dwellers are suffocated by their busy and stressful professional lives. They feel a need for places where they can find breathing-space in their free time. Green areas within towns are important spaces where townspeople are able to carry out recreational activities. These places form a link between townspeople and nature. The importance of urban green areas is increasing with every passing day due to their social, psychological, ecological, physical and economic functions and their impact on the quality of towns. In this study it has been attempted to demonstrate the pressures of urban development on agricultural land by determining the changing land use situation over the years in the district of Akhisar. In this research, an aerial photograph from year 1939 and satellite images of the town from the years 2000 and 2007 were used. Land use changes in the region were determined spatially. As a result of this study, which aims to determine in which direction urbanization is progressing in the district, the importance of town planning emerges. This study will be informative for the local authorities in their future town planning projects. With its flat and almost flat fertile arable land, the district of Akhisar occupies an important position within the province of Manisa. From the point of view of olive production the region is one of Turkey's important centres. Fifty-five percent of the olive production in the province of Manisa is realized in Akhisar. However, the results of the present study show that while agricultural areas comprised 2.5805 km(2) in 1939, these had diminished to 1.5146 km(2) in the year 2000 and had diminished to 1.0762 km(2) in the year 2007 and residential area (dense) 0.449 km(2) occupied in 1939, in the year 2000 this had risen to 1.9472 and 2.3238 km(2) in the year 2007. This planless urbanization in the study area has led to great losses of farmland.  相似文献   
177.
Cd, Ni, Cr, Zn, Cu and Pb concentrations of muscle tissue of 61 fish samples belonging to six fish species (Sparus auratus, Pomatomus saltatrix, Sarda sarda, Engraulis encrasicholus, Sander lucioperca, Scomber scombrus) retailed in Kayseri, Turkey were determined by flame atomic absorption spectrometry after wet digestion. Cd concentrations of at least 31 fish samples (50.8%) and Pb concentrations of at least six fish samples (9.8%) exceeded the corresponding Turkish permissible limit of 0.05 and 0.2 mg kg(-1) respectively whereas Zn concentrations of 11 fish samples (18%) exceeded the Turkish Food Codex limits of 50 mg kg(-1) for Zn. Cu concentrations of all fish species analyzed (100%) were below the corresponding Turkish legislations of 20 mg kg(-1). No limits were established concerning Ni and Cr concentrations in fish by the Turkish governmental authorities.  相似文献   
178.
Cu, Ni, Pb, Fe, Mn, Cr and Cd contents were determined in 17 different brands of chewing gum and candy samples available in local markets of Kayseri, Turkey. Concentration of selected trace metals were estimated using flame atomic absorption spectrometer after dry and wet digestion methods. Out of 17 brands of chewing gums and candies analysed, four were cocoa based, two were sugar based and other were of fruit based. Copper level ranged from 0.219 to 2.455 microg/g with an average of 1.390 microg/g. Nickel ranged from 0.120 to 2.588 microg/g with an average of 0.846 microg/g. Lead level ranged from 0.031 to 2.46 microg/g with an average of 0.746 microg/g. Iron level ranged from 3.963 to 9.863 microg/g with an average of 6.618 microg/g. Manganese level ranged from 1.872 to 5.067 microg/g with an average of 3.196 microg/g. Chromium ranged from 0.740 to 6.265 microg/g with an average of 2.473 microg/g and cadmium level ranged from 0.027 to 0.825 microg/g with an average of 0.296 microg/g. Cocoa based samples were found to have higher contents of the analysed metals than sugar and fruit based samples.  相似文献   
179.
There has been increasing concern in highlands of semiarid Turkey that conversion of these systems results in excessive soil erosion, ecosystem degradation, and loss of sustainable resources. An increasing rate of land use/cover changes especially in semiarid mountainous areas has resulted in important effects on physical and ecological processes, causing many regions to undergo accelerated environmental degradation in terms of soil erosion, mass movement and reservoir sedimentation. This paper, therefore, explores the impact of land use changes on land degradation in a linkage to the soil erodibility, RUSLE-K, in Cankiri–Indagi Mountain Pass, Turkey. The characterization of soil erodibility in this ecosystem is important from the standpoint of conserving fragile ecosystems and planning management practices. Five adjacent land uses (cropland, grassland, woodland, plantation, and recreational land) were selected for this research. Analysis of variance showed that soil properties and RUSLE-K statistically changed with land use changes and soils of the recreational land and cropland were more sensitive to water erosion than those of the woodland, grassland, and plantation. This was mainly due to the significant decreases in soil organic matter (SOM) and hydraulic conductivity (HC) in those lands. Additionally, soil samples randomly collected from the depths of 0–10 cm (D 1) and 10–20 cm (D 2) with irregular intervals in an area of 1,200 by 4,200 m sufficiently characterized not only the spatial distribution of soil organic matter (SOM), hydraulic conductivity (HC), clay (C), silt (Si), sand (S) and silt plus very fine sand (Si + VFS) but also the spatial distribution of RUSLE-K as an algebraically estimate of these parameters together with field assessment of soil structure to assess the dynamic relationships between soil properties and land use types. In this study, in order to perform the spatial analyses, the mean sampling intervals were 43, 50, 64, 78, 85 m for woodland, plantation, grassland, recreation, and cropland with the sample numbers of 56, 79, 72, 13, and 69, respectively, resulting in an average interval of 64 m for whole study area. Although nugget effect and nugget effect–sill ratio gave an idea about the sampling design adequacy, the better results are undoubtedly likely by both equi-probable spatial sampling and random sampling representative of all land uses.  相似文献   
180.
A method for the preconcentration of the total chromium based on coprecipitation with cerium (IV) hydroxide is proposed for determination of chromium by flame atomic absorption spectrometry. Different factors including carrier element amount, pH, sample volume and matrix ion effects for the precipitation were examined. The detection limit of the total chromium (k = 3, N = 15) was 0.18 μg l−1. The presented method was applied for the determination of chromium in the wastewater samples from Kayseri and Nigde Organized Industrial Region-Turkey and in drinking water from our laboratory, Kayseri with satisfactory results (relative standard deviations below 8%, recoveries 95%). The analytical results obtained by the proposed method for certified copper sample was in good agreement with the certified value.  相似文献   
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