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631.
Ali İhsan Kadioğullari Mehmet Ali Sayin Durmuş Ali Çelįk Süleyman Borucu Bayram Çįl Sinan Bulut 《Environmental monitoring and assessment》2014,186(4):2089-2110
This study analyses forest dynamics and land use/land cover change over a 43-year period using spatial-stand-type maps of temporal forest management plans of Karaisal? Forest Enterprise in the Eastern Mediterranean Region of Turkey. Stand parameters (tree species, crown closures and developmental stages) of the dynamics and changes caused by natural or artificial intervention were introduced and mapped in a Geographic Information System (GIS) and subjected to fragmentation analysis using FRAGSTATS. The Karaisal? Forest Enterprise was first planned in 1969 and then the study area was planned under the Mediterranean Forest Use project in 1991 and five-term forest management plans were made. In this study, we analysed only four periods (excluding 1982 revision plans): 1969, 1991, 2002 and 2012. Between 1969 and 2012, overall changes included a net increase of 3,026 ha in forested areas. Cumulative forest improvement accounted for 2.12 % and the annual rate of total forest improvement averaged 0.08 %. In addition, productive forest areas increased from 36,174 to 70,205 ha between 1969 and 2012. This translates into an average annual productive forest improvement rate of 1.54 %. At the same time, fully covered forest areas with crown closure of “3” (>70 %) increased about 21,321 ha, and young forest areas in developmental stage of “a” (diameter at breast height (dbh)?<?8 cm) increased from 716 to 13,305 ha over the 43-year study period. Overall changes show that productive and fully covered forest areas have increased egregiously with a focus on regenerated and young developmental stages. A spatial analysis of metrics over the 43-year study period indicated a more fragmented landscape resulting in a susceptible forest to harsh disturbances. 相似文献
632.
M. Ishaq Murad Ali Khan F. Akbar Jan I. Ahmad 《Environmental monitoring and assessment》2010,166(1-4):409-420
Environmental pollution is one of the burning issues of the world. In developed countries, there are lot of awareness about the environment and the impact of various industries on their life and surroundings. A little has been done in this direction in developing countries. In Pakistan, a big problem is the rapid conglomeration of the brick kilns in the outskirts of nearly all the urban centers to cope with the rapid construction work in big cities. A huge amount of low-grade coal or rubber tires is used as fuel in a very non-scientific manner. The purpose of the present study was to look into the impact of the brick kilns on the different aspects of environmental pollution caused by these kilns. Concentration of metals Cu, Co, Zn, Pb, Cr, Ni, Cd, and Mn were measured on 36 soil samples collected from the area and the same number of plant samples in order to establish the distribution of heavy metals in the area and to determine the effect of this distribution on the surrounding atmosphere and the possible effects on human life. 相似文献
633.
Çağatay Tanrıverdi Ahmet Alp Ali Rıza Demirkıran Fatih Üçkardeş 《Environmental monitoring and assessment》2010,167(1-4):175-184
In this study, surface water quality of the Ceyhan River basin were assessed and examined with 13 physico-chemical parameters in 31 stations in 3 months during the period of 2005. Multivariate statistical techniques were applied to identify characteristics of the water quality in the studied stations. Nutrients, Cl??? and Na?+? affected mostly to the stations of Erkenez 2, S?r 2, and S?r 3 in the ordination diagram of correspondence analysis. Three factors were extracted by principal component analysis, which explains 79.14% of the total variation. The first factor (PC1) captures variables of EC, DO, NO $_{2}^{\; -}$ , PO $_{4}^{\; \equiv }$ , Cl???, SO $_{4}^{\; =}$ , Na?+?, and Ca?+?+?. The second factor (PC2) is significantly related to pH, NH $_{3}^{\; -}$ , and Mg?+?+?, while water temperature (T) and NO $_{3}^{\; -}$ accounted for the greatest loading for factor 3 (PC3). The stations were divided into three groups for PC1, two groups for PC2, and three groups for PC3 by hierarchical cluster analysis. The stations in the vicinity of cities presented low dissolved oxygen and high concentration of physico-chemical parameter levels. The stations of Erkenez 2, S?r 2, S?r 3, and Aksu 4 located near the city of Kahramanmara? were characterized by an extremely high pollution due to discharge of wastewater from industry and domestic. P?narba?? and Elbistan stations were also influenced by household wastewater of the city of Elbistan. According to criteria of Turkish Water Pollution Control Regulation, Erkenez 2, S?r 2, and S?r 3 stations have high polluted water. This study suggests that it is urgent to control point pollutions, and all wastewater should be purified before discharge to the Ceyhan River basin. 相似文献
634.
This study was monitored to determine the changes in the micromineral and macromineral composition of common sole (Solea solea), striped red mullet (Mullus surmuletus), and whiting (Merlangius merlangus) throughout the year. Macromineral concentrations in edible parts of fish species were 444–1,559 mg/kg for Na, 1,975–5,130 mg/kg for K, 228–658 mg/kg for Mg, 187–1,105 mg/kg for Ca, and 2,341–7,341 for P, respectively. The highest mercury contents were found in the autumn months. While the highest protein and lowest fat values were found in the summer, the highest ash contents were found in the spring. Mercury content was found to be over the legislative limits in autumn samples for common sole and in summer for striped red mullet. Lead and cadmium contents of striped red mullet were found to be over the legislative limits throughout year. 相似文献
635.
Monitoring forest structure at landscape level: a case study of Scots pine forest in NE Turkey 总被引:1,自引:0,他引:1
This study aims to investigate the change in spatial-temporal configuration of secondary forest succession and generate measurements for monitoring the changes in structural plant diversity in Yaln?zçam Scots pine forest in NE Turkey from 1972 to 2005. The successional stages were mapped using the combination of Geographic Information System (GIS), Global Positioning System (GPS), aerial photos and high resolution satellite images (IKONOS). Forest structure and its relationship with structural plant diversity along with its changes over time were characterized using FRAGSTATS. In terms of spatial configuration of seral stages, the total number of fragments increased from 572 to 735, and mean size of patch (MPS) decreased from 154.97 ha to 120.60 ha over 33 years. The situation resulted in forestation serving appropriate conditions for plant diversity in the area. As an overall change in study area, there was a net increase of 1823.3 ha forest during the period with an average annual forestation rate of 55.25 ha year?1(0.4% per year). In conclusion, the study revealed that stand type maps of forest management plans in Turkey provide a great chance to monitor the changes in structural plant diversity over time. The study further contributes to the development of a framework for effective integration of biodiversity conservation into Multiple Use Forest Management (MUFM) plans using the successional stages as a critical mechanism. 相似文献
636.
Application of chemometrics in understanding the spatial distribution of human pharmaceuticals in surface water 总被引:1,自引:0,他引:1
Al-Odaini NA Zakaria MP Zali MA Juahir H Yaziz MI Surif S 《Environmental monitoring and assessment》2012,184(11):6735-6748
The growing interest in the environmental occurrence of veterinary and human pharmaceuticals is essentially due to their possible health implications to humans and ecosystem. This study assesses the occurrence of human pharmaceuticals in a Malaysian tropical aquatic environment taking a chemometric approach using cluster analysis, discriminant analysis and principal component analysis. Water samples were collected from seven sampling stations along the heavily populated Langat River basin on the west coast of peninsular Malaysia and its main tributaries. Water samples were extracted using solid-phase extraction and analyzed using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) for 18 pharmaceuticals and one metabolite, which cover a range of six therapeutic classes widely consumed in Malaysia. Cluster analysis was applied to group both pharmaceutical pollutants and sampling stations. Cluster analysis successfully clustered sampling stations and pollutants into three major clusters. Discriminant analysis was applied to identify those pollutants which had a significant impact in the definition of clusters. Finally, principal component analysis using a three-component model determined the constitution and data variance explained by each of the three main principal components. 相似文献
637.
Application of multivariate statistical approach to identify heavy metal sources in bottom soil of the Seyhan River (Adana), Turkey 总被引:1,自引:0,他引:1
M. Gurhan Yalcin Ali Tumuklu Mustafa Sonmez Dilek Satir Erdag 《Environmental monitoring and assessment》2010,164(1-4):311-322
In this study, freshly deposited soils were sampled from the Seyhan River (Turkey) from the exit of the Seyhan Dam to the Adana exit. Heavy metal contents were measured with X-ray fluorescence spectrometer. Multivariate statistical approach is used to identify the sources of heavy metals and other elements in soil samples. Considering the size of anomalies, metals are ranked as Co>Pb>Cr>Zn>Al. Based on the hierarchical cluster analysis results, three clusters were observed. P, Mg, Ti, Fe, Ca, Na, K, Al, Si, and Nb form the first cluster, Zn, Sr, Pb, and Cr associated as the second cluster, and Ba and Co form the third cluster. Three factors computed from principal component analysis are explained with a cumulative variance of 95%. The first factor is defined with “high background lithogenic factor” Co, the second factor with “local industrial factor” Pb, Cr, Ba, and Mg, and the third factor with “natural factor” Cr and Pb. 相似文献
638.
Mohammad Ali Hamzeh Majid Shah-hosseini Abdolmajid Naderi Beni 《Environmental monitoring and assessment》2013,185(2):1791-1807
In this study, the levels of natural and anthropogenic metal contamination (aluminum (Al), iron (Fe), manganese (Mn), arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu), nickel (Ni), lead (Pb), and zinc (Zn)) in surface sediments of three harbors along the Iranian coast of Gulf of Oman were examined and reported for the first time. Effect of grain size, mineralogy, normalization technique using Fe concentrations, and different sediment quality guidelines were discussed. Data from the harbors were compared with other harbors worldwide. Sediments inside the harbors are characterized by moderate and high levels of pollution by trace metals Cu (12–287 μg/g), Pb (11–1,780 μg/g), Zn (38–547 μg/g), Cr (70–2,370 μg/g), and Ni (31–116 μg/g). However, As and Cd did not show considerable pollution inside and outside the harbors. Considering that there is no industrial activity around the study harbors, the major sources of contamination in the harbors are repairing, fueling, greasing, and painting of fishing ships and boats. Mineralogy of sediments in the study area as well as trace metal concentration in reference samples taken from onshore geological units confirmed that natural inputs of Cd, Cu, Pb, and Zn in the harbors are very low while most of Ni and Cr contamination in the study area comes from erosion of ophiolitic mélange units at the North of Makran mountains. 相似文献
639.
640.