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81.
Modeling individual tree mortality for crimean pine plantations   总被引:1,自引:0,他引:1  
Individual tree mortality model was developed for crimean pine (Pinus nigra subsp. pallasiana) plantations in Turkey. Data came from 5 year remeasurements of the permanent sample plots. The data comprises of 115 sample plots with 5029 individual trees. Parameters of the logistic equation were estimated using weighted nonlinear regression analysis. Approximately 80% of the observations were used for model development and 20% for validation. The explicatory variables in the model were ratio of diameter of the subject tree and basal area mean diameter of the sample plot as measure of competition index for individual trees, basal area and site index. All parameter estimates were found highly significant (p < 0.001) in predicting mortality model. Chi-square statistics indicate that the most important variable is d / d(q), the second most important is site index, and the third most important predictor is stand basal area. Examination of graphs of observed vs. predicted mortality rates reveals that the mortality model is well behaved and match the observed mortality rates quite well. Although the phenomenon of mortality is a stochastic, rare and irregular event, the model fit was fairly good. The logistic mortality model passed a validation test on independent data not used in parameter estimation. The key ingredient for obtaining a good mortality model is a data set that is both large and representative of the population under study and the data satisfy both requirements. The mortality model presented in this paper is considered to have an appropriate level of reliability.  相似文献   
82.
In this study, the removal of color, chemical oxygen demand (COD) and aromatic group from one of the azo dyes, Remazol Yellow RR Gran, had been carried out by using one of the white rot fungi, Phanerochaete chrysosporium. Experimental studies were performed in growth media containing different amounts of dye and glucose. Color measurements were done at 436nm wavelength using spectrophotometer while aromatic group measurements were done at 280 nm wavelength using UV/Visible spectrophotometer. As a result of this study the values of the removable color concentration were determined as 10 mgl(-1) and lower. The optimum medium glucose concentration was determined to be 2 gl(-1) during color removal processes, aromatic group measurements were done in samples in the UV region at 280 nm wavelength. As a result of the measurements, it was shown that certain amount of aromatic group remained in the model wastewater at the end of the process.  相似文献   
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Environmental Science and Pollution Research - This study, which covered a set of leaching processes at a few stages, investigated the inclusion of iron found in mill scale, which is a waste of the...  相似文献   
86.
Cd concentrations in mobile phases of soil are more representative than total Cd concentration for estimating Cd bioavailability, physicochemical reactivity and mobility. In this study, selective sequential extraction procedures were used to determine Cd in different soil phases. Soil samples and plants grown in these soils were collected from a serpentine and copper-mining area in Maden-Elazig-Turkey. The extracted fractions were exchangeable/carbonate, reducible-iron/manganese oxides, oxidizable-organic matter and sulfides, and residual phases except silicates. Concentrations of Cd in soils and plant samples were determined by flame atomic absorption spectrometry and inductively coupled plasma-mass spectrometry. We found that Cd concentrations in the EDTA and NH2OH·HCl extracts are higher in most soil samples compared to the other extracts. We conclude that Cd levels in mobile phases are unexpectedly high. The observed Cd concentrations are in ranges of 0.03–3.4 mg kg−1 for soil and 0.02–2.5 mg kg−1 for plant parts. The percentages of cadmium up to 56% in exchangeable and carbonates fractions were observed to be significantly higher than in those values less than 2% reported in literature. This study has shown that the modified extraction method can be usefully applied to determine Cd concentrations in potentially mobile phase of soil. Furthermore, it was concluded that Brassicasea and Rumex leaves can be used as hyperaccumulator plants because their translocation factor and/or enrichment coefficient values were found to be higher than 1.0.  相似文献   
87.
Solar radiation data are required by solar engineers, architects, agriculturists, and hydrologists for many applications such as solar heating, cooking, drying, and interior illumination of buildings. In order to achieve this, numerous empirical models have been developed all over the world to predict solar radiation. The main objective of this study is to examine and compare 147 solar radiation models available in the literature for the prediction of monthly solar radiation at Ankara (Turkey) based on selected statistical measures such as percentage error, mean percentage error, root mean square error, mean bias error, and correlation coefficient. Our results showed that Ball et al. (Agron J 96:391?C397, 2004) model and Chen et al. (Energy Convers Manag 47:2859?C2866, 2006) model performed best in the estimation of solar radiation on a horizontal surface for Ankara.  相似文献   
88.
The study involves the Çe?me?CUrla Peninsula, where habitat fragmentation and loss, which threaten biological diversity, have become an urgent matter of concern in recent decades. The study area has been subjected to anthropogenic pressures and alterations due to ongoing and impending land uses. Therefore, ecological networks, as an appropriate way to deal with habitat fragmentation and loss and to improve ecological quality, were identified in the study area as one of the early attempts in the country to maintain its rich biodiversity. In this sense, core areas and ecological linkages as primary components of ecological networks were established on the basis of sustaining natural habitats. A GIS-based model was created to identify core areas and to facilitate the ecological connectivity. The modeling process for core areas and corridors combined 14 and 21 different variables, respectively. The variables were used as environmental inputs in the model, and all analyses were materialized in ArcGIS 9.2 using grid functions of image analysis and spatial analyst modules. As a result, six core areas and 36 corridor alternatives were materialized. Furthermore, some recommendations for the implementation and management of the proposed ecological networks were revealed and discussed.  相似文献   
89.
Noise pollution is a common health problem for developing countries. Especially highways and airports lead to noise pollution in different levels and in many frequencies. In this study, we focused on the effect of noise pollution in airports. This work aimed measurements of noise pollution levels in Van Ferit Melen (VFM) airport and effect of noise pollution over the immunoglobulin A, G, and M changes among VFM airport workers in Turkey. It was seen that apron and terminal workers were exposed to high noise (>80 dB(A)) without any protective precautions. Noise-induced temporary threshold shifts and noise-induced permanent threshold shifts were detected between the apron workers (p?<?0.001) and terminal workers (p?<?0.005). IgA values of apron terminal and control group workers were approximately the same in the morning and increased in a linear manner during the day. This increase was statistically significant (p?<?0.001). IgG and IgM values of apron, terminal, and control group workers were approximately same in the morning. Apron and terminal workers IgG and IgM levels were increased until noon and then decreased until evening as compare to control group, but these changes were not statically significant (p?>?0.05). These findings suggested that the noise pollution in the VFM airport could lead to hearing loss and changes in blood serum immunoglobulin levels of airport workers. Blood serum immunoglobulin changes might be due to vibrational effects of noise pollution. Airport workers should apply protective precautions against effect of noise pollution in the VFM airport.  相似文献   
90.

The concentrations and distribution of β-blockers, lipid regulators, and psychiatric and cancer drugs in the influent and effluent of the municipal wastewater treatment plant (WWTP) and the effluent of 16 hospitals that discharge into the wastewater treatment plant mentioned in this study at two sampling dates in summer and winter were examined. The pharmaceutical contribution of hospitals to municipal wastewater was determined. The removal of target pharmaceuticals was evaluated in a WWTP consisting of conventional biological treatment using activated sludge. Additionally, the potential environmental risk for the aquatic receiving environments (salt lake) was assessed. Beta-blockers and psychiatric drugs were detected in high concentrations in the wastewater samples. Atenolol (919 ng/L) from β-blockers and carbamazepine (7008 ng/L) from psychiatric pharmaceuticals were detected at the highest concentrations in hospital wastewater. The total pharmaceutical concentration determined at the WWTP influent and effluent was between 335 and 737 ng/L in summer and between 174 and 226 ng/L in winter. The concentrations detected in hospital effluents are higher than the concentrations detected in WWTP. The total pharmaceutical contributions from hospitals to the WWTP in summer and winter were determined to be 2% and 4%, respectively. Total pharmaceutical removal in the WWTP ranged from 23 to 54%. According to the risk ratios, atenolol could pose a high risk (risk quotient > 10) for fish in summer and winter. There are different reasons for the increase in pharmaceutical consumption in recent years. One of these reasons is the COVID-19 pandemic, which has been going on for 2 years. In particular, hospitals were operated at full capacity during the pandemic, and the occurrence and concentration of pharmaceuticals used for the therapy of COVID-19 patients has increased in hospital effluent. Pandemic conditions have increased the tendency of people to use psychiatric drugs. It is thought that beta-blocker consumption has increased due to cardiovascular diseases caused by COVID-19. Therefore, the environmental risk of pharmaceuticals for aquatic organisms in hospital effluent should be monitored and evaluated.

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