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31.
This study was conducted at a bottomland hardwood site with heavy textured soil in Akyazi, Turkey to determine the effect of initial spacing (3.0 x 3.0, 3.0 x 2.0, 2.5 x 1.6 and 2.5 x 1.2 m) and post-planting treatments (untreated check, moving, hoeing, disking, and hoeing plus disking) on early survival and growth of Fraxinus angustifolia Vahl. One-year old bare-root seedlings (70 +/- 5 cm in height) were hand-planted in December 2004. Through three years survival was perfect with a rate of 98% in all treatments. Spacing and the interaction between spacing and post-planting treatment did not significantly affect seedling growth through three years. However height and diameter growth increased overtime and differed significantly among post-planting treatments. The hoeing and hoeing plus disking treatments gave the highest growth, and resulted in about 31% increase in diameter and height increment, and in total diameter and height about 20%. These results suggest that post-planting treatments on bottomland sites with heavy textured soil give promising results.  相似文献   
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Chemical fractionation of seven heavy metals (Cd, Cr, Cu, Mn, Ni, Pb and Zn) was studied using a modified three-step sequential procedure to assess their impacts in the sediments of the Seyhan River, Turkey. Samples were collected from six representative stations in two campaigns in October 2009 and June 2010, which correspond to the wet and dry seasons, respectively. The total metal concentrations in the sediments demonstrated different distribution patterns at the various stations. Cadmium was the only metal that was below detection at all stations during both sampling periods. Metal fractionation showed that, except for Mn and Pb, the majority of metals were found in the residual fraction regardless of sampling time, indicating that these metals were strongly bound to the sediments. The potential mobility of the metals (non-residual fractions) is reflected in the following ranking: Pb > Mn > Zn > Cu > Ni > Cr in October 2009 and Mn > Pb > Zn > Cu > Ni > Cr in June 2010. The second highest proportion of metals was bound to organic matter/sulfides, originating primarily from anthropogenic activities. Non-residual metal fractions for all stations were highest in June 2010, which may be linked to higher organic matter concentrations in the sediment samples with 1.40% and 15.1% in October 2009 and June 2010, respectively. Potential sediment toxicity was evaluated using the Risk Assessment Code (RAC). Based on RAC classification, Cd and Cr pose no risk, Cu and Ni pose low risk, Pb and Zn were classified as medium risk metals, while the environmental risk from Mn was high. In addition, based on the sediment quality guidelines (SQG), the Seyhan River can be classified as a river with no, to moderate, toxicological risks, based on total metal concentrations.  相似文献   
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The sirenomelia sequence with fusion, rotation, hypotrophy or atrophy of the lower limbs in combination with severe urogenital and gastrointestinal malformations is a rare and usually lethal disorder. We present the case of a 28-year-old woman, who was referred to our department because of an intraabdominal cystic structure in the 9th week of gestation. Subsequent scans confirmed the diagnosis of a sirenomelia sequence with the fusion of the lower extremities without fusion of the bones according to Stocker I classification. The size of the intraabdominal cyst decreased during follow-up. After counseling, termination of pregnancy was induced. The postmortem X-ray confirmed the ultrasound diagnosis. The exact etiological mechanism of this malformation is still unknown. An early alteration of the embryological vascular network damaging the caudal mesoderm is thought to lead to arrested development of the lower limbs and other affected organs. The cyst we saw in the 9th week might fit with this theory, either as an expression of the complex malformation of the lower abdomen or as the sonographic appearance of necrosis. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   
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In this study, some heavy metal concentrations (Pb, Zn, Fe, Cr, Cu), suspended sediment, chemical oxygen demand (COD), biological oxygen demand (BOD), cyanide, phenol, fecal coliform and total coliform water parameters were determined in the streams (Kucuk Melen, Asarsuyu, Ugursuyu, Buyuk Melen and Aksu) of Buyuk Melen Watershed that provides drinking water to Istanbul in Western Black Sea Region of Turkey. Measurements of water quality parameters were done monthly in eleven separate stations (4 in Kucuk Melen Stream, 1 in Asarsuyu Stream, 1 in Ugur Stream, 1 in Aksu Stream and 4 in Buyuk Melen Stream) from August 2001 to August 2002. The seasonal changes in water quality parameters were evaluated statistically. The results, the parameters, COD, BOD, Pb, Zn, Fe, Cr, Cu, cyanide, fecal coliform, total coliform and suspended sediment showed significant differences among seasons and streams (ANOVA; P <0.05). According to Turkish Standarts (TS) 266, European Union (EU) and World Health Organization (WHO) criteria, the maximum values of each parameter in streams within the Buyuk Melen watershed are recorded and evaluated in this study.  相似文献   
36.
Sarikaya R  Yilmaz M 《Chemosphere》2003,52(1):195-201
A 96-h LC(50) values of 2,4-D [(2,4-dichlorophenoxy)acetic acid], a common contaminating agricultural herbicide, were determined on the adult common carp (Cyprinus carpio L., 1758; Pisces, Cyprinidae). The study was conducted in two stages using 130 carp. The data obtained were statistically evaluated by the use of the EPA computer program based on Finney's Probit Analysis Method and a 96-h LC(50) value for C. carpio L., 1758 was found to be 63.24 mg/l in a static bioassay test system. 95% lower and upper confidence limits for the LC(50) were 55.03 and 71.92 mg/l, respectively. Water temperature was 17+/-1 degrees C. Behavioral changes of the above mentioned species were examined for various herbicide concentrations.  相似文献   
37.
Concentration of Cd, Co, Cr, Ni, Zn, Fe, Mn, Pb and Cu were determinedin biota and sediment samples collected from the Marmara Sea in Turkey. The levels of Zn, Fe, Mn, Pb and Cu in the macroalgae are higher than previous studies in the Marmara Sea. Moreover, Cu and Zn concentrations at the present study are significantly high than Bosphorus and Black Sea algae. The order heavy metal concentrations in the mussel samples was: Fe > Zn > Ni > Mn > Cu > Pb > Cr > Cd > Co. The metal concentrations are generally lower when compared with the Black Sea mussels except Pb. At the same time, concentrations of Pb, Cu and Zn in the mussel species are lower when compared with the results in the Aegean Sea. The ranges of Mn and Cu in the tested fish samples are higher than Black Sea fish. On the other hand, Cd, Co, Cr, Zn and Pb concentrations are lower. The northern coast of the Marmara Sea having the highest metal concentrations in sediments as follows: Co, Cr, Ni, Fe at ?arköy ; Pb, Cu at M. Ere?li; Cd, Zn, Mn at Menek?e. The heavy metal levels in the sediment samples are lower than other areas in the Marmara Sea.  相似文献   
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Environmental Science and Pollution Research - The fatty acid composition of top-selling fish oil dietary supplements in the markets was compared with the content stated on product label, and their...  相似文献   
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This paper presents the growth response of 25 yr old Lebanon cedar (Cedrus libani A. Rich.) plantation to thinnings of different intensities in Isparta in western Turkey. The thinning intensity was measured by using the residual basal area (%) as parameter. In spring of 2005, three treatments were tested; light, moderate and heavy thinning with respectively 10, 25 and 35% of basal area removed. The statistical design of the experiment was a randomized incomplete block with two blocks and three treatments. Variables such as diameter at breast height (diameter) and height were measured. Growth rate ratios of diameter in moderately thinned and heavily thinned stands were 1.02 and 1.03, respectively. Basal area growth rates in moderately thinned and heavily thinned plots were 0.93 and 1.05, respectively. The largest values for the mean tree were observed with the heaviest thinning treatment. Absolute diameter increment was positively correlated with initial diameter in all plots. Relative diameter growth was negatively correlated with initial diameter. Growth rate interpretations were supported by analysis of variance using Duncan's test of range multiple. The results obtained show significant differences between treatments for tree height growth, for the two inventories carried out (2005, 2008). However diameter basal area and volume were no found between treatments for tree.  相似文献   
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