低效林分改造技术试验初报

A PRELIMINARY REPORT ON THE REFORESTATION REGIMES OF THE LOWER-PROTECTION-FUNCTION STANDS

以嘉陵江流域低山暴雨区水土保持低效林为研究对象，经过调查，选择旺苍县营造了林分改造试验林１０８亩，示范林３９００亩，试验林采用多因素正交法进行研究，经过栽培三年后的调查分析结果：柏林低效林分改造各试验组合的草本植物和灌木盖度比改造前增加１６．７～３３．３％和１８．３～４８．３％，乔木以桤木、柏木混义、中密度和培土的组合最佳；马尾松低效林分改造各试验组合的草本植物和灌木盖度增加３６．７～５３．３％和１３．４～１６．７％，乔木以马尾松、刺槐行带混交和中密度的组合最佳。由于经过改造的林地植被恢复快，土壤理化性质得到改善，土壤非毛管孔隙和总孔隙度增加，贮水能力明显提高。

Adapting the polycross trial method,the author studied the lower-protection -function stands.Three years after planting,the herds'and shrub'coverages increased by 16.7-33.3%and 18.3～48.3% in the reforestde Cypress stands,The mixural,modrerate density and soiling block of Cypress wity Alder stand presents the best,while in the Horse-tail pine stands, the coverage by 36.7-75.3%and 13.4-16.7%,best in line-stripe cross and modcrate-density pine with Locust tree.The general trands are that the reforestation tria can recover the plants cover,improve the soil properties as to increase the pole percentage and water-hold capability.