杉木不同造林方式效益分析

罗奋容

摘 要：从福建省洋口国有林场引进杉木2代苗木，通过炼山和不炼山2种方式在福建省沙县设立造林对比试验。结果显示：杉木不炼山方式造林比炼山方式造林投资高12.6%；杉木炼山方式造林前期生长比不炼山方式造林快，5a后渐渐持平，8a后不炼山方式造林显著优于炼山造林；炼山造林还导致土壤容重增大，土壤孔隙度降低，土壤变得紧实。

关键词：杉木；炼山；造林；土壤；生长量

中图分类号 S79 文献标识码 A 文章编号 1007-7731（2014）17-110-03

Abstract：The second generation of Chinese fir seedlings introduction，from the Yangkou Forest Farm，Fujian province in 2006.The forestation effect without soil preparation in the Sha county of Fujian province were studied.The main results were as follows：forestation investment without soil preparation was 39.2% more than controlled burning； on the early days，increment of forestation without soil preparation was slower than the other，they are the same after 5 years，but 8 years later，increment of forestation without soil preparation was faster than controlled burning markedly. The soil fertility of forestation without soil preparation was better as well. Soil bulk density was enlarged，soil porosity was reduced arised from the controlled burning，and the soil becomed tight.

Key words：Cunninghamia lanceolata（lamb.）Hook；Controlled burning；Forestation；Soil；Increment

杉木（Cunninghamia lanceolata（Lamb.）Hook）是松柏目杉科乔木，具有分布广、材性好、生长快、用途广等特点[1-3]。杉木喜气候温暖，空气湿度大的丘陵山地，要求土壤深厚、肥沃、富含有机质[4]。杉木在我国的栽培历史逾1 000a，是我国重要的用材树种[5]，也是南方各省区最重要的造林树种[6]。闽北是杉木的核心产区，长期以来大面积营造杉木纯林。

炼山整地挖穴造林是闽北地区杉木重要的传统技术[7]。随着杉木人工林面积的不断扩大，杉木人工林地力衰退问题日益严重。杨玉盛等提出炼山是导致杉木人工林地力衰退的主要原因之一[8]。大量研究表明炼山容易造成水土流失、土壤板结、地力下降、森林火灾[9]。近年来，政府部门一再明令禁止炼山造林，但在贯彻执行中却难以落实，炼山禁而不止[10]。为了改变传统观念，大力推广不炼山造林，笔者在沙县夏茂镇中堡村、月邦村开展杉木山地不炼山与传统炼山造林的对比试验，分析比较不炼山与传统炼山造林的单价与林分生长效果。现将试验研究结果报道如下。……