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881.
Because of their intense vegetation and the fact that they include areas of coastline, deltas situated in the vicinity of big cities are areas of great attraction for people who wish to get away from in a crowded city. However, coasts, with their fertile soil and unique flora and fauna, need to be protected. In order for the use of such areas to be planned in a sustainable way by local authorities, there is a need for detailed data about these regions. In this study, the changes in land use of the area between Topburnu and Uçburun Musa Bey Harbour on the Çe?me peninsula, which is to the immediate west of Turkey’s third largest city ?zmir, from 1976 up to the present day, were investigated. In the study, using aerial photographs taken in 1976, 1995 and 2000 and an IKONOS satellite image from the year 2007, the natural and cultural characteristics of the region and changes in the coastline were determined spatially. Using aerial photographs from 1976, 1995 and 2000 and an IKONOS satellite image from the year 2007, together with “1/25,000 scale Conservation-Oriented Development Plans” prepared in 1979, 1990 and 2000 by the committee for the Preservation of Natural and Cultural Entities attached to the Ministry of Culture and Tourism of the Turkish Republic, the natural and cultural characteristics of the region and the land use changes and their connection with conservation rulings were determined spatially. In this study, spatial changes in land use over the years were compared with changing conservation rulings over the years and the emerging results have brought a new perspective to the subject in contrast to other similar studies. 相似文献
882.
Sources of errors and uncertainties in the assessment of forest soil carbon stocks at different scales—review and recommendations 总被引:1,自引:0,他引:1
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886.
Alfredo Montero Alvarez Juan R. Estévez Alvarez Clístenes Williams Araújo do Nascimento Iván Pupo González Oscar Díaz Rizo Lázaro Lima Carzola Roberto Ayllón Torres Jorge Gómez Pascual 《Environmental monitoring and assessment》2017,189(1):28
Epiphytic lichens, collected from 119 sampling sites grown over “Roistonea Royal Palm” trees, were used to assess the spatial distribution pattern of lead (Pb) and identify possible pollution sources in Havana (Cuba). Lead concentrations in lichens and topsoils were determined by flame atomic absorption spectrophotometry and inductively coupled plasma (ICP) atomic emission spectrometry, respectively, while Pb in crude oils and gasoline samples were measured by ICP-time of flight mass spectrometry (ICP-ToF-MS). Lead isotopic ratios measurements for lichens, soils, and crude oils were obtained by ICP-ToF-MS. We found that enrichment factors (EF) reflected a moderate contamination for 71% of the samples (EF > 10). The 206Pb/207Pb ratio values for lichens ranged from 1.17 to 1.20 and were a mixture of natural radiogenic and industrial activities (e.g., crude oils and fire plants). The low concentration of Pb found in gasoline (<7.0 μg L?1) confirms the official statement that leaded gasoline is no longer used in Cuba. 相似文献
887.
Phthalocyanines are prospective chemicals that have applications in industry, medicine and biology due especially to their architectural flexibility and production of reactive oxygen species. Although they are used in so many areas of human activities nowadays, there is still little knowledge of their ecotoxicity. Here we present the first observation of their toxic effects on representatives of the aquatic plants Lemna minor. The tested phthalocyanines possess a wide spectrum of phytotoxicity ranging from seldom (>50 mg L−1) to highly toxic 0.11 mg L−1. Moreover, the potential of phthalocyanines to be used as selective cyanocides or herbicides is discussed as well. 相似文献
888.
Polláková J Kovalkovičová N Csank T Pistl J Kočišová A Legáth J 《Journal of environmental science and health. Part. B》2012,47(6):538-543
There is an increasing need for rapid and easily interpreted in vitro assays to screen for possible cytotoxicity of pesticides. The objective of this study was to investigate the effect of the carbamate insecticide bendiocarb on mammalian and insect cell cultures. The cytotoxicity of this insecticide was evaluated by cell proliferation and cellular damage was assessed by evaluation of the cytopathic effect and lactate dehydrogenase (LDH) leakage. Cells of insect origin (Sf21) were the most sensitive to bendiocarb with significant (P < 0.01) suppression of their proliferative activity ranging from 10(-1)-10(-5) M. However, significant suppression of proliferative activity was also recorded in rat liver cells (WBF344; 10(-1)-10(-3) M; P < 0.01-0.05) and rabbit kidney cells (RK13; 10(-1) M; P < 0.01). In contrast with the proliferation activity of cells, a cytopathic effect based on cellular damage and LDH leakage into the medium was observed only at the highest concentration (10(-1) M) in RK 13 and WBF344 cells, but not in the Sf21 insect cell line. Our results indicate that bendiocarb exposure caused a cell-type dependent decrease in cell proliferation; however, cell damage and LDH leakage into the medium were not present or were strongly limited, dependent on the cell phenotype. Cell proliferation was shown as a sensitive indicator for evaluation of the cytotoxic effect of bendiocarb in vitro; on the other hand, microscopic signs of cellular damage and LDH leakage were insufficient in vitro markers. 相似文献
889.
García-Rosales G Olguin MT Colín-Cruz A Romero-Guzmán ET 《Environmental science and pollution research international》2012,19(1):177-185
Objective
The present work was carried out to investigate the effects of temperature, initial pH, initial concentration, and contact time on the biosorption of lead (Pb) and cadmium (Cd) by modified stalk sponge of Zea mays using a batch technique. 相似文献890.
Jay Krishna Thakur P. K. Srivastava S. K. Singh Zoltán Vekerdy 《Regional Environmental Change》2012,12(1):133-144
Wetland ecosystems are of global significance having productive, regulatory and informative function. These wetlands are crucial
for the long-term protection of water sources, as well as the survival of its unique biodiversity. Most of the wetlands of
Turkey are now facing serious threat from the anthropogenic sources and now near to the verge of extinction. This study has
been carried out to monitor vegetation dynamics and ecological status of wetlands of Koyna basin at spatial and temporal scale.
This study has involved MODerate-resolution Imaging Spectroradiometer (MODIS) images of the year 2000, 2004 and 2008 on daily
basis with spatial resolution of 1 km. The MODIS 16 days composite NDVI time series products of 250-m spatial resolution from
year 2000 to 2008 has been utilized to monitor the ecological status of the wetlands. The European Nature Information System
habitat classification map, meteorological data (precipitation, temperature) coupled with field data has been utilized to
validate NDVI values of nine habitats in the wetlands. The time series analyses of NDVI data values have been correlated with
the groundwater level depth from 1996 to 2004. The overall analysis has shown a declining trend of NDVI over the year 2000
to 2008, indicated a degraded wetland condition in span of 9 years. 相似文献