南亚热带退化植被重建中土壤动物群落变化

在广东省中部的鹤山市鹤山丘陵综合试验场,分别在草坡、松林、荷木混交林(荷混林)、马占相思林(马占林)和豆科混交林(豆混林)选取5块样地,分别代表5种处理方式(重建植被类型)。在2003~2004年的4个不同季度内分3层取土样,利用Tullgren干漏斗法采集土壤动物,并分析土壤动物群落个体数量、类群丰度和DG指数的变化。研究结果表明,季节、植被类型和土层深度对土壤动物群落的各项指标都有极显著影响(P<0·01,three-way-ANOVA):土壤动物群落指标,在秋季显著为高(P<0·05,DMRT),而夏季显著为低(P<0·05,DMRT);随土层加深而逐级显著降低;不同植被类型比较,豆混林>马占林>荷混林、松林和草坡。此外,植被类型还与季节和土层间存在显著的交互作用:土壤动物群落各项指标秋季最高,不同植被类型间的差异也最大;而土壤动物群落各项指标较高的植被类型内不同土层间的差异也较大。由此推测,对退化生态系统进行人工改造是有积极意义的,而不同植被类型间土壤动物的差异可能与凋落物的数量与质量密切相关。

Changes of Soil Fauna During Forest Restoration in Subtropical China

Changes of soil fauna communities were studied by Tullgren dry funnel method in the grassland, pine, mixed Schima superba, Acacia mangium and mixed Acacia forests during four seasons of 2003-2004 at the Heshan Research Station. It suggested that there were significant effects of season, plantation and soil depth on soil fauna (P<0.01, three-way-ANOVA). Soil fauna were conspicuously abundant in autumn (P<0.05, DMRT), but conspicuously succinct in summer (P<0.05, DMRT). Soil fauna decreased significantly (P<0.05, DMRT) into deeper soil and most of them concentrated in 0-5 cm soil layer. The order of all plantations was mixed Acacia forest > Acacia mangium forest > mixed Schima superba forest, pine forest and grassland. Significant interaction can also be found between plantation and season, and plantation and soil depth respectively. Soil fauna varied mostly in different plantations in autumn when soil fauna developed to the highest level, and the differences of soil fauna were discovered largely among soil depths with better plantation. It was concluded that man-made reconstruction to ecological system was beneficial to forest restoration, and the differences among various plantations might be correlated closely to the amount and quality of the litter in the forests.