毛竹雷公藤混农经营技术与固土保水功能

连续7 a毛竹雷公藤混农经营试验表明,采取“中间带状”混农经营模式种植雷公藤,毛竹林的密度应控制在2100-2400株.hm-2。该密度不仅利于笋用林和笋竹两用林的经营,还使雷公藤平均基径增粗23.3%,平均支数增加20%。混农经营的林分由于雷公藤的覆盖,毛竹林地免遭雨水直接袭击,此外,雷公藤落叶与宿根还有保持水土,改良土壤的作用。与毛竹纯林相比,混农经营地土壤结构和水分性状得到一定程度的改良,表土层>0.25 mm的水稳性团聚体含量增加3.17%,结构体破坏率降低4.51%,土壤持水量增加37.4%,水源涵养量增加736.513 t.hm-2。

Management model of the agroforest of Phyllostachys heterocycla and Tripterygium wilfordii and its effect on soil and water conservation

The agroforest management of Phyllostachys heterocycla and Tripterygium wilfordii has been conducted for 7 years.The results showed that the density of P.heterocycla forest should be controlled between 2100-2400 individuals per hectare when T.wilfordii was planted in intermediate reticular region with agroforest model.It can benefit for shoot stand management and shoot-bamboo double-using forest.The average basal diameter of T.wilfordii was increased by 23.3% and its branch was increased by 20%.Meanwhile,the agroforest of P.heterocycla prevented to be assaulted by rain because of the cover of T.wilfordii.Compared with P.heterocycla pure forest,the soil structure and water character were improved by falling leaves and roots of T.wilfordii,and>0.25 mm composition of aggregates of subsurface soil,water holding capacity,and water conservation capacity increased by(3.2%,)(37.4%,)736.513 t·hm~(-2)respectively,while structure destructive rate of the soil decreased by 3.7%.