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为推广应用稻草型生物有机肥,采用田间小区试验研究了稻草型生物有机肥对萝卜(Raphanus sativus)功能叶叶绿素含量、碳氮代谢关键酶活性、萝卜产量和品质的影响.结果表明:稻草型生物有机肥处理Ⅰ与等NPK养分施用量的纯化肥处理Ⅱ和菜枯肥处理Ⅲ相比,可提高萝卜功能叶叶绿素含量、防止功能叶早衰;提高硝酸还原酶、蔗糖合成酶、蔗糖磷酸合成酶三种碳氮代谢关键酶活性.处理Ⅰ使萝卜的产量分别比处理Ⅱ和处理Ⅲ提高4.48%、6.01%,维生素C分别提高22.48%、28.24%,可溶性糖含量分别提高10.39%、19.91%,萝卜硝酸盐含量分别下降8.78%和16.67%,且以上4个指标处理Ⅰ与处理Ⅱ和处理Ⅲ的差异均达极显著水平,此外亚硝酸盐含量也明显降低. 相似文献
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Risk to humans of consuming metals in anchovy (<Emphasis Type="Italic">Coilia</Emphasis> sp.) from the Yangtze River Delta 总被引:1,自引:0,他引:1
Fengyan Liu Jiachun Ge Xin Hu Teng Fei Yuehua Li Yuan Jiang Zhiqiang Xu Shuyan Ding John P. Giesy 《Environmental geochemistry and health》2009,31(6):727-740
Concentrations of metals were determined in four species of anchovy (Coilia sp.) from the Yangtze River, Taihu Lake, and Hongze Lake in Jiangsu Province, China. Concentrations of Cr in anchovy fish
muscle ranged from 2.6 × 10−2 to 5.0 mg/kg ww, and Coilia nasus taihuensis in Jiaoshan, Taihu Lake contained the highest concentrations of Cr, which was almost 111-fold higher than the mean value
at other locations. Concentrations of Pb ranged from 1.5 × 10−2 to 1.3 × 10−1 mg/kg ww. Comparisons of concentrations of lead (Pb) among the four species indicated that anadromous species contained higher
concentrations of Pb than did freshwater species. However, concentrations of Pb in C. nasus from the Nanjing and Haimen locations in the Yangtze River were not significant higher than those of two freshwater species:
C. nasus taihuensis from Taihu Lake and C. brachygnathus from Hongze Lake (Duncan’s test, α = 0.05). While concentrations of Cd and Zn ranged from 7.0 × 10−4 to 3.6 × 10−3 mg/kg ww and 3.4 to 4.8 mg/kg ww, respectively, there were no significant differences in concentrations among the eight locations.
The only concentration of the metals studied that exceeded the Chinese National Standard was Cr in Coilia from Jiaoshan, Taihu Lake, which was 2.5-fold higher than the standard. These results indicate that people who consume the
genus Coilia are not at risk due to concentrations of metals, except Cr in C. nasus taihuensis from Jiaoshan in Taihu Lake. Concentrations of all of the metals studied except for Cr were similar to or less than those
of metals in most other areas in the world. 相似文献
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Hongyuan WANG Xiaolu JIANG Ya HE Huashi GUAN 《Frontiers of Environmental Science & Engineering》2009,3(2):194-199
Four typical coastal sites (rocky shore, sandy shore, mud flat shore, and artificial harbor) at the Yellow Sea were chosen to investigate the spatial and seasonal variations in bacterial communities. This was accomplished by using terminal restriction fragment length polymorphism (T-RFLP) analysis of PCR amplified 16S rDNA fragments. Two kinds of tetrameric restriction enzymes, HhaI and MspI, were used in the experiment to depict the bacterial community diversity in different marine environments. It was found that the community compositions digested by the two enzymes separately were different. However, the results of bacterial community diversity derived from them were similar. The MDA analysis results of T-RFLP profiles coming from HhaI and MspI both exhibited a significant seasonal community shift for bacteria and a relatively low spatial variation among the four locations. With HhaI as the sample, the pair wise T-tests also revealed that variations were minor between each pair of marine environments, with R ranging from 0.198 to 0.349. However, the bacterial community structure in the mud flat site depicted a larger difference than each of the other three sites (R ranging from 0.282 to 0.349). 相似文献
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模拟评价方法及其在安全与环境评价中的应用 总被引:11,自引:2,他引:9
对现有评价方法进行了简要的分类并重点分析了常用评价方法的优缺点。提出了模拟评价方法的概念 ,介绍了模拟评价方法的思想、评价步骤、技术关键及作为一种新的评价方法的优缺点 ,指出了模拟评价方法今后的发展方向。针对某工厂新建项目 ,利用模拟评价方法进行了有毒气体单元泄漏后果评价 ,评价结果与环境预评价结果吻合程度较好 ,表明模拟评价方法作为一种新的评价方法不但具有形象、直观、易于理解等优点 ,而且其评价结果准确度较高 ,可靠性良好 ,是现有评价方法的必要及有益的补充 相似文献