本文選題：杉木人工林　切入點(diǎn)：間伐　出處：《中南林業(yè)科技大學(xué)》2015年碩士論文

【摘要】：土壤作為陸地生態(tài)系統(tǒng)的最大碳庫(kù),是森林可持續(xù)發(fā)展的重要組成部分。土壤呼吸對(duì)全球碳平衡和溫室效應(yīng)具有十分重要的意義。土壤微生物群落結(jié)構(gòu)對(duì)維持植物正常生長(zhǎng)、土壤肥力以及物質(zhì)能量代謝循環(huán)具有決定性作用。杉木是我國(guó)亞熱帶主要造林樹種,在我國(guó)南方林業(yè)生產(chǎn)和生態(tài)建設(shè)中占有重要地位。研究間伐和修枝對(duì)杉木人工林土壤呼吸及微生物群落結(jié)構(gòu)的影響,可為林業(yè)生產(chǎn)實(shí)踐中最大限度發(fā)揮人工林固碳能力而制定適宜的經(jīng)營(yíng)措施提供理論依據(jù)和技術(shù)支持。本研究以會(huì)同縣杉木人工林為研究對(duì)象,對(duì)土壤呼吸的季節(jié)變化規(guī)律、土壤呼吸和土壤微生物群落結(jié)構(gòu)對(duì)土壤理化性質(zhì)和環(huán)境因素的響應(yīng)以及間伐和修枝對(duì)土壤呼吸和土壤微生物群落結(jié)構(gòu)的影響進(jìn)行了研究,研究結(jié)果表明：(1)杉木人工林土壤呼吸的季節(jié)變化整體上呈單峰曲線。不同森林經(jīng)營(yíng)措施下土壤呼吸的季節(jié)變化規(guī)律相似,土壤呼吸速率最大值出現(xiàn)在夏季的7、8、9月,最小值則出現(xiàn)在溫度較低的2月。整體上來(lái)說(shuō),對(duì)照(CK)、間伐(T)和修枝(P)三種處理土壤呼吸速率由大到小依次為PTCK,均值分別為1.76μmol·m-2·s-1、1.65μmol·m-2·s-1和1.58μmol·m-2·s-1。(2)溫度是土壤呼吸最關(guān)鍵的影響因素。三種處理樣地中土壤呼吸與土壤溫度均呈極顯著正相關(guān)(p0.01),土壤溫度能解釋土壤呼吸變化的90%以上。土壤呼吸與土壤含水量、土壤pH、土壤微生物量碳(MBC)、土壤蔗糖酶、淀粉酶和p-葡萄糖苷酶的相關(guān)性均不顯著(p0.05)。對(duì)照、間伐樣地土壤呼吸與細(xì)菌、真菌和放線菌的數(shù)量均呈負(fù)相關(guān),修枝樣地土壤呼吸則與其呈正相關(guān)。(3)間伐和修枝對(duì)土壤溫度、土壤含水量和土壤pH無(wú)顯著影響,間伐和修枝均降低了土壤蔗糖酶和p-葡萄糖苷酶的活性,間伐降低了土壤淀粉酶活性,修枝增加其活性。不同森林經(jīng)營(yíng)措施月平均土壤呼吸速率無(wú)明顯差異,間伐和修枝后土壤呼吸在1、3、4月顯著上升,間伐后土壤呼吸在7、9、11月顯著下降。(4)土壤微生物數(shù)量與土壤溫度、土壤pH相關(guān)性不顯著(p0.05),與土壤含水量、MBC、土壤全C、全N和C/N呈正相關(guān)。間伐顯著降低了土壤中MBC、全C、全N含量,修枝降低土壤中MBC含量,增加土壤全C、全N含量。間伐和修枝均降低了土壤細(xì)菌、真菌、放線菌、革蘭氏陽(yáng)性菌和革蘭氏陰性菌的數(shù)量以及微生物總數(shù)。
[Abstract]:As the largest carbon pool in terrestrial ecosystem, soil is an important part of forest sustainable development.Soil respiration plays an important role in global carbon balance and Greenhouse Effect.The structure of soil microbial community plays a decisive role in maintaining the normal growth of plants, soil fertility and the cycle of substance and energy metabolism.Cunninghamia lanceolata (Cunninghamia lanceolata) is the main afforestation tree in subtropical region of China.The effects of thinning and pruning on soil respiration and microbial community structure of Chinese fir plantation can provide theoretical basis and technical support for making the best use of carbon sequestration ability in forestry production.In this study, Chinese fir plantation in Huitong County was used as the research object, and the seasonal variation of soil respiration was studied.The responses of soil respiration and soil microbial community structure to soil physical and chemical properties and environmental factors, and the effects of thinning and pruning on soil respiration and soil microbial community structure were studied.The results showed that the seasonal variation of soil respiration in Chinese fir plantation showed a single peak curve.The seasonal variation of soil respiration under different forest management measures was similar. The maximum of soil respiration rate appeared in 7 / 8 in summer and the lowest in September and the lowest in February when the temperature was lower.鏁翠綋涓婃潵璇，

本文編號(hào)：1711726