施肥时间对毛竹林生产力分配格局及土壤性质的影响

Effects of Fertilizer Application Time on Distribution Pattern of Productivities and Soil Properties of Phyllostachys edulis Forests

以福建省永安市天宝岩自然保护区不施肥毛竹林(Ⅰ)为对照,对施肥5 a(Ⅱ)和施肥13 a(Ⅲ)毛竹林的生产力分配格局和土壤性质演变特征进行了研究。结果表明:施肥能显著提高毛竹林的生产力。3种类型毛竹林生产力排列顺序为Ⅰ<Ⅱ<Ⅲ,分别为(35 443.98±1 583.41)、(47 364.87±1 735.93)、(53 614.93±2 086.70)kg.hm-2.a-1,与未施肥毛竹林生产力相比,施肥5 a毛竹林生产力提高了41.15%,施肥13 a毛竹林生产力提高了58.35%。随着施肥时间的延长,毛竹林地上部分生产力质量分数呈下降趋势,林分Ⅰ为73.79%,林分Ⅱ为73.62%,林分Ⅲ为72.16%。毛竹林土壤因子综合得分的排列顺序为Ⅰ>Ⅱ>Ⅲ,分别为0.569 3、0.428 6和0.374 4。长期施肥的毛竹林在获得较高生产力的同时,消耗了土壤更多的有机质、全氮、速效氮,土壤的综合肥力指数降低。相关性分析表明,土壤密度、全氮和水解氮质量分数与生产力极显著负相关,与土壤非毛管孔隙度显著或极显著正相关,进一步证实了施肥可以降低土壤密度,增加土壤非毛管孔隙度,但会加速土壤全氮、水解氮的消耗。

An experiment was conducted to study the effects of fertilizer application time on distribution pattern of productivities and soil properties of Phyllostachys edulis forests in Yongan County,Fujian Province.Results showed that the productivity of P.edulis forests increased significiantly after fertilization.The productivities were 53 614.93±2 086.70,47 364.87±1 735.93 and 35 443.98±1 583.41 kg·hm-2·a-1 for the bamboo forests Ⅲ（thirteen years of continuous application of fertilizer）,Ⅱ（five years of continuous application of fertilizer）,and Ⅰ（without fertilization）,respectively.The productivities of bamboo forests Ⅱ and Ⅲ increased by 41.15% and 58.35% respectively compared with Ⅰ.The proportions of above-ground productivity decreased with the application time,and they were 73.79%,73.62% and 72.16% for bamboo forests Ⅰ,Ⅱ and Ⅲ,respectively.The comprehensive scores were 0.569 3,0.428 6,and 0.377 4 forⅠ,Ⅱ and Ⅲ respectively.The bamboo forest Ⅲ exhibited higher productivity,but much organic matter,total nitrogen and available nitrogen were consumed;therefore,the soil integrated fertility index decreased with the prolonged application time.There were significant negative correlations between the productivity of bamboo and total nitrogen,available nitrogen and soil bulk density,and a significant or extremely significant positive correlation between the productivity of bamboo and non-capillary porosity.It indicates that fertilizer application could reduce soil bulk density and increase soil non-capillary porosity,while promote consumption of total nitrogen and available nitrogen.