不同經(jīng)營方式的云冷杉針闊混交林土壤真菌群落結構1)

劉志宇 張忠輝 楊凱麟 張軍 姜潤華 吳則甫 王琦 李文華 夏富才

(吉林省林業(yè)科學研究院,長春,130033)(北華大學)

To assess the effects of different management practices in spruce-fir forests, the Spruce-fir mixed forest in Wangqing Forestry Bureau of Jilin Province was taken as the research object, and four management methods were set up. The traditional management: the canopy density was above 0.7 after felling.Target tree management 1: felling was carried out according to target tree single plant management, and the target tree density of timber was reserved to 100 ind·ha-1. Target tree management 2: felling was carried out according to target tree single plant management, and the target tree density of timber was kept at 150 ind·ha-1. The 3 uncut pairs are also denoted as CK. Through high-throughput sequencing technology and soil physicochemical analysis, the differences of soil bacterial community structure under different management methods were compared. The results showed that: (1)There were significant differences in soil chemistry between management practices (p<0.05). (2)Logging increased the number of OTU and OTU of fungi in Spruce-fir mixed forest. (3)α diversity analysis showed that target tree management 1 had the most abundant fungal community, while traditional tree management had the highest fungal community diversity. (4)β diversity analysis showed that the difference between different management methods was significantly higher than that between groups, suggesting that logging changed the species composition of fungal community. Therefore, the dominant microbial community of soil fungi had different responses to disturbance, and the soil quality decreased due to logging. After logging, the composition of soil fungi tended to be supported by saprophytic bacteria. Soil fungal community structure showed different similarities under different management methods, and harvesting changed the fungal community structure compared to the control operation, indicating that the soil fungi did not stabilize after a short period of recovery after harvesting. In conclusion, harvesting can affect soil fungi for a short period of time, and it facilitates nutrient cycling by soil fungal communities. From the analysis of fungal abundance, community structure and similarity, target tree management 2 was closer to the control group, so target tree management 2 was superior to other management methods.

土壤中微生物是陸地生態(tài)系統(tǒng)中的重要組成部分，是森林生態(tài)系統(tǒng)中能量流動、物質循環(huán)、信息傳遞的重要驅動者[1]，是全球生物多樣性的重要組成部分[2]，對陸地生態(tài)系統(tǒng)有著重要作用[3]。土壤真菌通過調節(jié)一些關鍵的生化過程來影響森林生產力，如有機質分解、養(yǎng)分循環(huán)、土壤肥力的維持、土壤碳的固定、植物養(yǎng)分吸收等[4-6]。土壤性質例如碳氮質量比、pH、速效磷質量分數(shù)等在決定土壤真菌群落的結構、多樣性方面作用巨大[7-8]，并且土壤理化性質又受到森林經(jīng)營方式的顯著影響[9-11]。

隨著研究的深入，近幾年的研究表明：農田地和造林土壤的優(yōu)勢真菌門為子囊菌門(Ascomycota)、接合菌門(Zygomycota)和擔子菌門(Basidiomycota)，但造林土壤中接合菌門的相對豐度較農田地大[12]；森林采伐或樹冠間伐將顯著增加土壤異養(yǎng)真菌的呼吸，從而增加土壤CO2排放總量[13]；對黑松林分進行間伐處理，發(fā)現(xiàn)其表層土壤內真菌微生物豐度和微生物群數(shù)均顯著高于對照處理的同齡林分土壤[14]；遼東山區(qū)日本落葉松人工林的土壤真菌差異隨林齡增加而加大，并且真菌比細菌更為顯著[15]；在貴州茂蘭喀斯特森林，陽坡的凋落物對真菌群落的影響較大，并且凋落物中的碳、磷質量分數(shù)與真菌群落有極顯著的正相關性[16]。以上研究表明，經(jīng)營方式通過改變林分空間結構，影響森林內的土壤環(huán)境，進而影響了土壤真菌，說明真菌對外界變化敏感。……