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1.
本文根据当前畜牧业生产形势结合凉山实际,就凉山绿色肉羊基地建设问题进行了一些思考,并提出了相应对策建议. 相似文献
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C_R704玉米与S_C704玉米各时期的过氧化物酶同功酶谱无明显差别,二者遗传基础一致,但酶活性C_R704玉米高于S_C704玉米。经测定三系杂种C_R704玉米在叶绿素、糖、淀粉及蛋白质含量均优于单交种S_C704玉米。 相似文献
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The major role of DNA polymerase β was thought to be limited in its involvement in short patch base excision repair by removing 5’-deoxyribose phosphate and base insertion. However, the recent researches indicate that polymerase β might take part in a wide spectrum of DNA metabolism reactions, including long patch base excision repair, DNA replication, recombination, meiosis and transleisional DNA synthesis. Because of its wide and important cellular function, an inappropriate intracellular polymerase β level might be associated with genomic instability. Down-regulation or mutation of polymerase β is mutagenic due to deficient in DNA repair, while overexpression of this error-prone β polymerase might perturb the normal function of other accurate polymerases and cause genomic instability as well. 相似文献
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减少底肥施用量增加叶面施肥次数对玉米产量的影响 总被引:1,自引:0,他引:1
该试验目的是研究降低底肥施用量但是增加叶面肥施用次数方面对玉米产量的变化规律,旨在找出最经济的施肥方式以达到在保护环境的基础上提高经济效益的目的。试验表明,玉米产量随着底肥施用量的增加而提高,并且叶面肥喷施次数越多产量越高,每喷一次,可增加产量258~592.5 kg/hm2,增产幅度2.3%~5.6%。 相似文献
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农业生产基地项目具有影响范围大、产品服务多元化等特点,涉及行业类别较多,其环境影响评价文件也相对复杂。环境影响评价报告编制单位应充分与建设方进行沟通,熟悉项目建设内容,挖掘项目可能的产生污染的环节和设施,明确环境影响范围和环境敏感点,并对项目损益进行两方面的分析。 相似文献
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Soil erosion in mountain rangelands in Kyrgyzstan is an emerging problem due to vegetation loss caused by overgrazing. It is further exacerbated by mountain terrain and high precipitation values in Fergana range in the south of Kyrgyzstan. The main objective of this study was to map soil erodibility in the mountainous rangelands of Kyrgyzstan. The results of this effort are expected to contribute to the development of soil erodibility modelling approaches for mountainous areas. In this study, we mapped soil erodibility at two sites, both representing grazing rangelands in the mountains of Kyrgyzstan and having potentially different levels of grazing pressure. We collected a total of 232 soil samples evenly distributed in geographical space and feature space. Then we analyzed the samples in laboratory for grain size distribution and calculated soil erodibility values from these data using the Revised Universal Soil Loss Equation (RUSLE) K-factor formula. After that, we derived different terrain indices and ratios of frequency bands from ASTER GDEM and LANDSAT images to use as auxiliary data because they are among the main soil forming factors and widely used for prediction of various soil properties. Soil erodibility was significantly correlated with channel network base level (geographically extrapolated altitude of water channels), remotely sensed indices of short-wave infrared spectral bands, exposition, and slope degree. We applied multiple regression analysis to predict soil erodibility from spatially explicit terrain and remotely sensed indices. The final soil erodibility model was developed using the spatially explicit predictors and the regression equation and then improved by adding the residuals. The spatial resolution of the model was 30 m, and the estimated mean adjusted coefficient of determination was 0.47. The two sites indicated different estimated and predicted means of soil erodibility values (0.035 and 0.039) with a 0.05 significance level, which is attributed mainly to the considerable difference in elevation. 相似文献