本文選題：亞高寒草甸　切入點(diǎn)：坡向　出處：《生態(tài)環(huán)境學(xué)報》2017年11期

【摘要】：為了探究坡向變化對土壤微生物群落分布的影響,采用稀釋涂布平板法和最大可能數(shù)(MPN)法測定了亞高寒草甸3年間(2014年、2015年和2016年)不同坡向土壤微生物類群及2016年微生物功能群的分布特征,并分析了微生物類群及功能群分布與植物生物量、土壤理化性質(zhì)等環(huán)境因子的關(guān)系。結(jié)果表明,不同坡向土壤微生物群落分布差異顯著(P0.05),由陽坡向陰坡變化時,土壤微生物類群總數(shù)整體呈上升趨勢。同一坡向土壤細(xì)菌數(shù)量所占比例最大,放線菌次之,真菌最小;2016年微生物總數(shù)較2014年與2015年分別下降了61.75%和68.23%。土壤微生物功能群總數(shù)隨陽坡向陰坡變化呈現(xiàn)先增加后減少的趨勢,氨化細(xì)菌數(shù)量顯著高于固氮菌與硝化細(xì)菌數(shù)量(P0.05)。相關(guān)分析表明,亞高寒草甸坡向梯度上土壤微生物群落分布是多種環(huán)境因子共同作用的結(jié)果,其中,土壤含水量、全磷和土壤p H值是影響土壤微生物類群分布的主導(dǎo)因子,固氮菌、硝化細(xì)菌數(shù)量與有機(jī)碳含量相關(guān)性達(dá)到顯著水平。綜合分析表明,陰坡土壤環(huán)境明顯優(yōu)于陽坡,更適宜土壤微生物進(jìn)行生命活動。
[Abstract]:To explore the effects of slope changes on the distribution of soil microbial communities, The distribution characteristics of soil microbial groups and microbial functional groups in subalpine meadow for three years (2014, 2015 and 2016) were determined by dilution coating plate method and maximum maximum number of MPN method. The relationship between the distribution of microbial groups and functional groups and environmental factors, such as plant biomass, soil physical and chemical properties, was also analyzed. The results showed that the distribution of soil microbial communities in different slope directions was significantly different (P0.05), and the variation from the positive slope to the shady slope was significant. The total number of soil microbes was on the rise. The proportion of bacteria in the same slope was the largest, followed by actinomycetes. The total number of microorganisms in 2016 was 61.75% and 68.23% lower than that in 2014 and 2015, respectively. The total number of soil microbial functional groups increased first and then decreased with the change of the positive slope to the negative slope. The number of ammoniated bacteria was significantly higher than that of nitrogen-fixing bacteria and nitrifying bacteria (P0.050.The correlation analysis showed that the distribution of soil microbial community on the gradient of subalpine meadow slope was the result of various environmental factors, among which, soil water content. Total phosphorus and soil pH were the main factors affecting the distribution of soil microbial groups. The correlation between the amount of nitrogen-fixing bacteria, nitrifying bacteria and the content of organic carbon reached a significant level. The comprehensive analysis showed that the soil environment of shady slope was obviously superior to that of sunny slope. It is more suitable for life activities of soil microbes.
【作者單位】： 西北師范大學(xué)地理與環(huán)境科學(xué)學(xué)院;
【基金】：國家自然科學(xué)基金項目(31360114;31760135)
【分類號】：S812.2
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本文編號：1676109