发酵床垫料降解特性及氮素变化研究

发布时间：2018-08-12 11:55

【摘要】：随着社会的快速发展,传统的畜禽散养模式与耕地资源的矛盾日益凸显,由此带来的环境污染也日趋严重。发酵床养殖模式中,畜禽的一切生命活动都是在垫料上进行,垫料的管理与维护成为该模式的关键。因此,探讨不同垫料中有机质的降解情况和影响因素,以及垫料中氮素形态的转化规律和对垫料下层土壤的影响就显得很有意义,这将有助于在实际养猪过程中选择适当的垫料配比,根据环境效应对猪场的使用年限作出正确的评估。本研究选择南京六合发酵床猪舍和泗阳天蓬猪场作为研究对象,研究不同垫料中木质素、纤维素、半纤维素等的降解特性；通过测定含水率、pH值、C/N以及垫料中酶活性等的变化对影响垫料降解的因素进行探究；分析垫料及垫料下层土壤中不同形态氮素的变化来研究氮素的转化特性,并为科学使用发酵床、减轻环境承载提供理论支撑。主要试验结论如下：(1)在养殖过程中,以稻壳和木屑为原料的垫料纤维素、半纤维素、木质素含量的下降幅度都小于添加酒糟、菌糠的垫料；各处理的垫料C/N均有所下降,其下降速率受垫料组成成分的影响,添加酒糟、菌糠的处理的下降速度更快。(2)随着垫料使用时间的延长,三种不同垫料的纤维素在有机质中的占比均呈下降趋势,而木质素的占比均升高；在由稻壳和木屑组成的垫料中,其半纤维素所占的比例略微升高,而添加酒糟、菌糠的垫料的半纤维素在有机质中的占比下降。(3)在0-40cm垫料层中,随着深度的加大,各处理酶活性都有不断降低的趋势；在垫料下层40-80cm土壤中,随着时间推移,酶活性均略微上升。(4)在发酵床垫料中,过氧化氢酶活性和纤维素酶活性随着垫料使用时间的延长而显著增加,而蛋白酶活性则相反。(5)发酵床中垫料经过长时间使用,其含水量会逐步下降,为了保证垫料对猪粪尿的正常消化降解,应及时适量补充水分；垫料中pH值在6.0～8.5范围内变化,能够满足微生物正常发酵的需要。(6)垫料总氮、碱解氮和硝态氮含量均呈现不断增加趋势,而铵态氮含量随着垫料使用时间的加长而有所降低。(7)垫料中有机质含量持续下降,而垫料下层土壤中氮素和有机质含量则呈现增大趋势。
[Abstract]:With the rapid development of the society, the contradiction between the traditional animal husbandry model and cultivated land resources is increasingly prominent, and the environmental pollution is becoming more and more serious. In the fermentation bed breeding model, all life activities of livestock and poultry are carried out on the cushion, and the management and maintenance of the cushion become the key of the model. Therefore, it is of great significance to discuss the degradation of organic matter in different mats and its influencing factors, as well as the transformation law of nitrogen forms in the gasket and the effect on the underlying soil of the bedding. This will be helpful to select the appropriate proportion of bedding in the actual pig raising process and make a correct assessment of the service life of the pig farm according to the environmental effect. In this study, the degradation characteristics of lignin, cellulose and hemicellulose in different liners were studied by using Nanjing Hexahe fermenting bed and Siyang Tianpeng Pig Farm as the research objects. The factors affecting the degradation of the gasket were investigated by measuring the water content and pH value of C / N and the enzyme activity in the gasket, and the conversion characteristics of nitrogen were studied by analyzing the changes of different forms of nitrogen in the soil of the cushion and the underlying soil. It also provides theoretical support for scientific use of fermenting bed and lightening environmental load. The main conclusions are as follows: (1) during the breeding process, the contents of cellulose, hemicellulose and lignin in rice husk and sawdust were decreased less than those in distiller's grains and bacterial chaff, and the C / N of all treatments decreased. The decreasing rate was affected by the composition of the gasket. The treatment of bacterial chaff decreased more quickly with the addition of distiller's grains. (2) with the prolongation of the use time of the gasket, the proportion of cellulose in organic matter of three different kinds of mats showed a decreasing trend. The proportion of hemicellulose in the gasket composed of rice husk and wood chips increased slightly, while the proportion of hemicellulose in organic matter decreased with the addition of distiller's grains. (3) in the 0-40cm cushion, the proportion of hemicellulose in organic matter decreased. With the increase of the depth, the enzyme activity of each treatment decreased continuously, and in the 40-80cm soil under the cushion, the enzyme activity increased slightly with the passage of time. (4) in the fermentative bed bedding, the enzyme activity increased slightly with the increase of the depth. The activity of catalase and cellulase increased significantly with the increase of the time of use of the mats, but the activity of protease was opposite. (5) the water content of the mats in the fermenting bed decreased gradually after a long period of use. In order to ensure the normal digestibility and degradation of pig manure and urine, it is necessary to replenish water in proper amount in time, and the pH value in the gasket varies within the range of 6.0 ~ 8.5, which can meet the needs of microbial normal fermentation. (6) the total nitrogen of the gasket, The content of alkali-hydrolyzed nitrogen and nitrate-N both showed an increasing trend, while the content of ammonium nitrogen decreased with the increase of the use time of the gasket. (7) the content of organic matter in the gasket decreased continuously. The contents of nitrogen and organic matter in the underlying soil increased.
【学位授予单位】：扬州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：S815

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