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81.
养护管理措施对地震后退化草坪恢复的影响 总被引:1,自引:1,他引:0
2008年6~7月对地震后搭建帐篷的不同退化程度草坪,采用4种恢复方式进行定位试验,开展草坪特征(草坪草绿色盖度、高度、密度、裸斑盖度、杂草盖度和高度等参数)和维管植物多样性调查。采用一般线性模型中的单变量多因素方差分析研究了处理方式,恢复时间以及二者的交互作用对草坪恢复的影响。研究结果表明:(1)随着搭建帐篷时间的延长,草坪的退化程度加剧。重度退化草坪较轻度退化草坪恢复需要更长的时间。(2)施肥加浇水较其他方式能显著提高轻度退化草坪草绿色盖度,降低枯落物盖度,增加杂草盖度。4种恢复方式对重度退化草坪恢复特征没有差异。(3)恢复1个月后,重度退化草坪草的盖度从1.80%±0.39%恢复到8.90%±2.51%,轻度退化草坪草的盖度从7.78%±1.79%恢复到10.98%±2.75%,恢复效果较差。恢复后草坪植物组成和丰富度发生了明显的变化。杂草从5种增加到19种。草坪草无芒雀麦的优势地位被生长速度快的莎草科植物单穗水蜈蚣和阔叶类植物积雪草代替。综合分析表明:以无芒雀麦为优势种的草坪受避灾干扰的影响较大,养护管理措施并不能促进轻度和重度退化草坪草的快速恢复,应采取重建方式进行恢复。 相似文献
82.
A method using possibility theory and fuzzy logic is introduced. Possibility functions of each feature are determined during training. Methods of fuzzy logic are used to combine the possibility of different features. This Chinese character recognition system consists of a pre-classifier and a two-level fine classifier. In order to handle deviations of the characters,a fuzzification of features is introduced. This method is used to develop single-font classifiers. The whole system consists of a font-classifiers and four single-font-classifiers. 相似文献
83.
李斌 《农业图书情报学刊》2009,21(10):206-208
阐述了高校合并后,图书馆对系统合并的要求以及在系统合并的过程中存在的问题。并结合河南工业大学图书馆系统合并,对系统整合中遇到的问题提出了具体的整合思路和应对措施。 相似文献
84.
本文提出了高校图书馆附书光盘网络化管理模式的,必要性,以湖南农业大学图书馆为例,对光盘网络化管理实践进行了全面地探讨. 相似文献
85.
The mathematical relationship for assessing total energy consumption within a material life cycle is presented in this paper. According to the relationship,the procedure rationality of recycling waste may be assessed quantitatively. 相似文献
86.
文章依据对西安儿童公园改造提升重新开放后进行实地调研的结果,总结西安儿童公园的景观设计特点、存在的问题及儿童公园的发展方向。
相似文献
87.
《The Journal of Applied Poultry Research》2008,17(2):305-314
Limited data on pollutant emissions from poultry operations are available to assess the effect of these operations on the environment and to put their contribution in perspective with other sources of pollutants. To alleviate this problem, numerous studies at various poultry facilities have been undertaken to improve the knowledge base in quantifying emissions of NH3 and size-fractionated particulate matter (PM). For these emission data to be of practical use for government agencies and policy makers, the emission rates must be reported as an emission factor with a production unit that enables the emissions from one poultry operation to be correlated to another poultry operation. This paper presents a compilation of NH3 and PM emission data from several studies in the form of emission factor on a per-500 kg of live weight or animal unit basis. In addition, best management practices that lower pollutant emissions from poultry operations have been reported along with their effectiveness at reducing NH3 and PM. Unfortunately, the compiled data were insufficient to characterize the variability in emissions caused by differences in house design, suggesting that more studies are needed to complete a comprehensive emission inventory. Once complete, this inventory will enable poultry producers to estimate emissions from their facilities and, if necessary, select management practice(s) to lessen their emissions of NH3, PM, or both. 相似文献
88.
陶竹林 《农业机械化与电气化》2014,(11):91-92
以梁山镇费岗子村村民参加新民市阳光工程为例,介绍新民市开展阳光工程项目的效果,从政府推动、培训基地审核、项目监管方面,探讨新民市在阳光工程项目实施过程中采取的主要措施和方法,为基层市县开展阳光工程提供参考。 相似文献
89.
Enzyme and glycogen structure studies have been carried out on tissues of a glycogenotic dog, the clinical and pathological characteristics of which are reported in the accompanying paper. Liver glucose-6-phosphatase, leukocyte and liver acid maltase, and liver and skeletal muscle glycogen Phosphorylase all appeared largely unaffected. The activity of the muscle and liver debranching enzyme (amylo-l,6-glucosidase), determined by two independent assay methods, was, however, reduced to between 0 and 7 % of normal activity. Glycogen structure studies with Phosphorylase or iodine spectra revealed that the abnormally large amounts of glycogen found in liver and skeletal muscle had abnormally short branches, as would be expected for a deficiency of debranching enzyme. It is thus clear that the dog had suffered from the equivalent of Cori''s disease (limit dextrinosis, type III glycogen storage disease). Preliminary data indicate that it may be possible to identify heterozygotes based on a study of the debranching enzyme of leukocytes. 相似文献
90.
On basis of the experiment on sixteen high strength concrete columns, their shear behaviors are analysed. The effects of shear-span ratio and axial compression ratio on failure behavior, cracking shear and shear strength are analysed. The authors have discussed the suitability of the design equations for shear strength in the code. This experimental study on shear strength of high strength concrete frame columns is the first one in this field at home and the results can be served as reference for the code of high strength concrete design. 相似文献