【摘要】：土壤微生物在農(nóng)田生態(tài)系中對土壤生態(tài)、結(jié)構(gòu)、水文等方面均有重大的影響。微生物在不同類型土壤中的數(shù)量和結(jié)構(gòu)具有明顯的差異,可反映土壤的環(huán)境和肥力狀況,因此系統(tǒng)而科學(xué)地認(rèn)識各微生物空間分布特征及其影響因素,對農(nóng)田科學(xué)灌溉施肥、土壤微生物保護(hù)等具有重要意義。本研究采用大田原位試驗與室內(nèi)實驗結(jié)合的方法,歷時三年采樣和實驗,運(yùn)用地統(tǒng)計學(xué)、經(jīng)典統(tǒng)計學(xué)等理論,多角度分析土壤中細(xì)菌、放線菌、真菌、固氮菌、氨化細(xì)菌、硝化細(xì)菌和反硝化細(xì)菌的空間分布特性,及其對土壤環(huán)境因子的響應(yīng),研究結(jié)果如下:(1)土壤中微生物數(shù)量具有顯著的垂直結(jié)構(gòu),隨著土壤深度的增加微生物數(shù)量呈減少趨勢,但在某一些深度上變異性較強(qiáng),細(xì)菌、放線菌、固氮菌、亞硝酸菌、反硝化細(xì)菌數(shù)量在200cm深度附近變化顯著。(2)同種微生物在灌溉入滲過程中響應(yīng)不同,不同微生物對同一環(huán)境因子相關(guān)性大小有顯著的差異。有機(jī)質(zhì)與細(xì)菌數(shù)量的相關(guān)性在入滲中表現(xiàn)為灌后10天灌后30天灌后4天灌前,與固氮則表現(xiàn)為灌前灌后30天灌后10天灌后4天。(3)灌溉影響微生物的數(shù)量和組成,隨著灌溉時間的推移,影響會逐漸的減小,大約30天后恢復(fù)至灌前的水平。灌溉入滲過程中,微生物數(shù)量與土壤有機(jī)質(zhì)、總氮和C/N均呈正相關(guān),與pH、水分、銨態(tài)氮呈負(fù)相關(guān),而在不同灌溉時期影響程度也不同。(4)微生物半方差函數(shù)擬合表明,微生物在某一深度上具有較強(qiáng)的空間依賴性,變程大小可反應(yīng)微生物變異性。灌前細(xì)菌、放線菌、真菌分別為線性模型、高斯模型、高斯和線性模型,而固氮菌、氨化菌、硝酸菌和反硝化菌在整個剖面上呈現(xiàn)不同的擬合模型,其中放線菌和固氮菌均表現(xiàn)出強(qiáng)烈的空間依賴性。灌溉入滲中淺層土壤中微生物空間變異性較強(qiáng),深層減弱。(5)狀態(tài)空間模擬表明,不同的季節(jié)模擬結(jié)果具有差異,在夏季土壤總氮、有機(jī)質(zhì)和溫度是影響固氮菌的重要變量,土壤水分、溫度、pH、有機(jī)質(zhì)以及氨氮、硝氮和總氮是影響春夏氨化細(xì)菌空間分布的重要因素;土壤有機(jī)質(zhì)、氮素底物和溫度是影響硝化細(xì)菌的重要變量,其中溫度的作用在春夏遠(yuǎn)大于冬季;反硝化細(xì)菌空間分布受土壤溫度的控制;春、夏、冬季中土壤有機(jī)質(zhì)、溫度、pH、水分和總氮、硝氮是影響細(xì)菌總數(shù)、真菌和放線菌的重要變量。根據(jù)模擬的結(jié)果,可用于區(qū)域上微生物分布特征的預(yù)測。
[Abstract]:Soil microorganisms have great influence on soil ecology, structure, hydrological and so on in farmland ecosystem. The quantity and structure of microorganisms in different types of soil are obviously different, which can reflect the environment and fertility of soil. Therefore, the spatial distribution characteristics of microorganisms and their influencing factors are systematically and scientifically understood, and the farmland is irrigated and fertilized scientifically. Soil microbial protection is of great significance. In this study, the method of field in situ test and laboratory experiment was used to analyze bacteria, actinomycetes, fungi, nitrogen fixing bacteria and ammonia bacteria in soil by means of geostatistics and classical statistics. The spatial distribution characteristics of nitrifying bacteria and denitrifying bacteria and their response to soil environmental factors are as follows: (1) the number of microorganisms in soil has a significant vertical structure. With the increase of soil depth, the number of microorganisms showed a decreasing trend, but in a certain depth, the variability was strong, bacteria, actinomycetes, nitrogen-fixing bacteria, nitrous acid bacteria, The number of denitrifying bacteria changed significantly near the depth of 200cm. (2) the response of the same microorganism to the same environmental factor was different, and the correlation between different microorganisms to the same environmental factor was significantly different. The correlation between organic matter and bacterial count in infiltration was as follows: 10 days after irrigation, 30 days after irrigation, 4 days after irrigation, and nitrogen fixation was shown as 4 days after irrigation 30 days after irrigation. (3) Irrigation affected the number and composition of microorganisms. With the passage of irrigation time, the effect will gradually decrease and return to the pre-irrigation level after about 30 days. During irrigation infiltration, the number of microorganisms was positively correlated with soil organic matter, total nitrogen and C / N, and negatively correlated with pH, moisture and ammonium nitrogen. The degree of influence is also different in different irrigation periods. (4) the fitting of microbial semi-variance function shows that microorganisms have strong spatial dependence at a certain depth, and the variable range size can reflect microbial variability. Before irrigation, bacteria, actinomycetes and fungi were linear model, Gao Si and linear model, respectively, while nitrogen-fixing bacteria, ammonia bacteria, nitrate bacteria and denitrifying bacteria showed different fitting models on the whole profile. Actinomycetes and nitrogen-fixing bacteria showed strong spatial dependence. The spatial variability of microorganisms in shallow soil of irrigation infiltration is strong and the deep layer is weakened. (5) the state space simulation shows that the simulation results of different seasons are different, and the total nitrogen of soil in summer is different. Organic matter and temperature are important variables affecting nitrogen-fixing bacteria. Soil moisture, temperature, pH, organic matter, ammonia nitrogen, nitrate nitrogen and total nitrogen are important factors affecting the spatial distribution of ammonia-fixing bacteria in spring and summer. Soil organic matter, nitrogen substrate and temperature are important variables affecting nitrifying bacteria, in which the effect of temperature is much greater in spring and summer than in winter, and the spatial distribution of denitrifying bacteria is controlled by soil temperature. Soil organic matter, temperature, pH, water and total nitrogen, nitrate nitrogen are important variables affecting the total number of bacteria, fungi and actinomycetes in spring, summer and winter. According to the simulation results, it can be used to predict the distribution characteristics of microorganisms in the region.
【學(xué)位授予單位】：長安大學(xué)
【學(xué)位級別】：碩士
【學(xué)位授予年份】：2017
【分類號】：S154.3

【參考文獻(xiàn)】

相關(guān)期刊論文 前10條

1 魏佳寧;馬紅梅;邵新慶;張建全;余群;柴琦;鐘夢瑩;;三江源區(qū)土壤微生物和土壤養(yǎng)分空間分布特性研究[J];中國土壤與肥料;2016年02期

2 肖燁;黃志剛;武海濤;呂憲國;;三江平原典型濕地類型土壤微生物特征與土壤養(yǎng)分的研究[J];環(huán)境科學(xué);2015年05期

3 倪紹忠;師慶東;楊建軍;王濤;張文俊;;基于本土材料的土壤基質(zhì)改良及對草本植被恢復(fù)的影響分析[J];新疆農(nóng)業(yè)科學(xué);2013年05期

4 李娜;張利敏;張雪萍;;土壤微生物群落結(jié)構(gòu)影響因素的探討[J];哈爾濱師范大學(xué)自然科學(xué)學(xué)報;2012年06期

5 張利青;彭晚霞;宋同清;鄒冬生;曾馥平;宋敏;俞孜;劉艷;;云貴高原喀斯特坡耕地土壤微生物量C、N、P空間分布[J];生態(tài)學(xué)報;2012年07期

6 史文嬌;岳天祥;石曉麗;宋偉;;土壤連續(xù)屬性空間插值方法及其精度的研究進(jìn)展[J];自然資源學(xué)報;2012年01期

7 馬玲;丁新華;顧偉;馬偉;;扎龍季節(jié)性濕草甸土壤養(yǎng)分和土壤微生物特性[J];應(yīng)用生態(tài)學(xué)報;2011年07期

8 王曉龍;徐立剛;姚鑫;白麗;張奇;;鄱陽湖典型濕地植物群落土壤微生物量特征[J];生態(tài)學(xué)報;2010年18期

9 羅希茜;郝曉暉;陳濤;鄧嬋娟;吳金水;胡榮桂;;長期不同施肥對稻田土壤微生物群落功能多樣性的影響[J];生態(tài)學(xué)報;2009年02期

10 劉榮花;朱自璽;方文松;鄧天宏;趙國強(qiáng);;冬小麥根系分布規(guī)律[J];生態(tài)學(xué)雜志;2008年11期

相關(guān)碩士學(xué)位論文 前1條

1 張明;豫中煙區(qū)土壤養(yǎng)分空間變異及其管理分區(qū)[D];河南農(nóng)業(yè)大學(xué);2010年

，

本文編號：2488050