摘要
[目的]研究间伐对杉木人工林土壤微生物数量、酶活性及关系的影响,试图了解不同间伐强度作用下土壤恢复的过程和机制,为人工林经营提供理论依据。[方法]以18年生杉木人工林为研究对象,采用随机区组试验设计,分析4种间伐强度TS0(未间伐(0.0%),1 800株·hm-2)、TS1(轻度(16.7%),1 500株·hm-2)、TS2(中度(33.3%),1 200株·hm-2)和TS3(重度(50.0%),900株·hm-2)下杉木人工林土壤微生物数量及土壤酶活性特点,探讨土壤微生物数量与酶活性的相关性。[结果]表明:间伐3年后,林下土壤层酶活性和微生物数量显著提高,不同土层间土壤微生物数量和酶活性均差异显著;间伐显著提高了土壤过氧化氢酶、碱性磷酸酶、脲酶和蔗糖酶的活性,除过氧化氢酶(15 30、30 45 cm)、碱性磷酸酶(0 15、30 45 cm)以及脲酶(30 45 cm)以TS3处理的酶活性最高外,其他酶活性在各土层和不同间伐强度下均以TS2处理的酶活性最高;土壤各层微生物以细菌数量最多,其次是放线菌,硝化细菌最少,且TS2处理的微生物数量最多。土壤过氧化氢酶和脲酶活性均与细菌、真菌和硝化细菌数量呈极显著正相关,与放线菌数量呈极显著负相关,氨化细菌数量与过氧化氢酶活性呈负相关,而与脲酶活性呈正相关;碱性磷酸酶活性与细菌、真菌和硝化细菌数量呈正相关,与氨化细菌数量呈极显著负相关,与放线菌数量呈负相关;蔗糖酶活性与细菌、真菌和氨化细菌数量呈极显著正相关,与硝化细菌数量呈正相关,与放线菌数量呈负相关。[结论]间伐改善了林分环境、光照、温度以及林下植被的发育,提高了林下土壤酶活性并增加了微生物数量。间伐3年后的综合表现表明,中度间伐最利于杉木人工中、近熟林阶段的经营,对于改善土壤性质较好。
[Objective] In order to understand the process and mechanism of soil restoration under different thinning intensities, and provide theoretical basis for management of plantation, the impact of thinning intensity on soil enzyme activity and microorganisms in Cunninghamia lanceolata plantation and the interaction between them were studied. [Method] 18-year-old C. lanceolata plantations in Rongjiang county of Guizhou province were studied with random block experiments. The soil enzyme activity and soil microorganisms under 4 different thinning intensities, TS0 （no thinning （0.0%）, 1 800 trees·hm^-2）, TS1 （mild （16.7%）, 1 500 trees·hm^-2） and TS2 （moderate （33.3%）, 1 200 trees·hm^-2） and TS3 （severe （50.0%）, 900 trees·hm^-2） were analyzed, the correlation of soil microorganisms and soil enzyme activities were also revealed. [Result] After 3 years＇ thinning, both the enzyme activities and microorganism amounts in soil layer significantly increased, the differences in soil microbe amount and enzyme activity among different soil layers were significant, and the activities of soil catalase, phosphatase, urease and invertase significantly increased. The activities of catalase （15-30 cm and 30-45 cm）, alkaline phosphatase （0-15 cm and 30-45 cm） and urease（30-45 cm）in treatment TS3 were higher than that in other treatments, while the activities of the other enzymes in different soil layers and different intensities were higher in treatment TS2. The amount of bacteria was the most in each layer, followed by actinomyces and nitrifying bacteria. The amount of microorganisms in treatment TS2 was more than that in other treatments. The activities of urease and catalase had very significantly positive correlation with the amounts of bacteria, fungi and digestion, while they were very significantly negative correlation with actinomycetes. The amount of ammonifying bacteria had negative correlation with hydrogen peroxide enzyme activity, and had positive correlation with urease activity. The activities of phosphatase had positive correlation with the amounts of bacteria, fungi and nitrifying bacteria, and had very significantly negative correlation with ammonifying bacteria amount, and had negative correlation with actinomycetes amount. The activities of invertase had very significantly positive correlation with the amount of bacteria, actinomyces, and ammonifying bacteria, and had positive correlation with amount of nitrifying bacteria, and had negative correlation with actinomycetes. [Conclusion] The forest environment, light, temperature and the growth of vegetation were improved after thinning, and the soil enzyme activities and the amount of microorganisms increased. The general performances after 3 years＇ thinning indicated that middle thinning intensity is the best in the management of near-mature C. lanceolata plantations and improvement of soil properties.
出处
《林业科学研究》
CSCD
北大核心
2017年第6期1059-1065,共7页
Forest Research
基金
贵州省重大专项(黔科合重大专项字[2012]6011号)
贵州省林业重大专项(黔林科合[2011]重大0l号)
贵州省农业科技攻关(黔科合NY字[2012]3027号)
关键词
杉木
人工林
间伐强度
土壤微生物
土壤酶活性
Cunninghamia lanceolata
plantation
thinning intensity
soil microbes
soil enzyme
