普文试验林场森林土壤养分状况研究

Nutrient Status of Forest Soil in Puwen Experimental Forest Farm

为了解普文试验林场土壤养分状况,通过土壤类型调查和基本理化性质测定,采用修正的内梅罗综合指数法对土壤进行肥力评价。结果表明,普文试验林场土壤为紫色砂岩上发育的赤红壤,土壤pH值总体属于酸性水平且随土层加深酸性减弱。A层SOM含量高,随土层加深呈高—中—低明显变化。N含量水平高,随土层加深含量下降,但仍能达到中等及以上水平。土壤P素十分缺乏,区域内各土层AP大部分处于较缺乏水平,少部分区域极度缺乏。土壤K素较丰富,且随土层加深有升高趋势,可被植物利用的AK仅少部分区域处于丰富水平,大部分处于较缺水平。中量元素中AS基本与同区域农田土壤中含量处于同一水平,EMg含量较低,ECa十分缺乏。微量元素基本与同区域农田土壤中含量处于同一水平或略高。受生物富集过程影响,土壤养分表现出较明显的“表聚性”,大部分区域土壤肥力等级为中等肥沃,少数为贫瘠水平,土壤养分含量呈现出随海拔升高而下降的变化趋势。

In order to understand the soil nutrient status of Puwen Experimental Forest Farm,soil types was identified base on the investigation,physical and chemical properties was measured and Nemerow index method was used to evaluate soil fertility.The results showed that the soil in the forest farm was latosolic red soil developed from purple sandstone.The soil pH was generally acidic,and the acidity decreased with the deepening of the soil.SOM content in the A-layer was high,and the content showed a significant change of high—medium—low with the deepening of the soil.N content was high,and the content decreased with the deepening of the soil,but could also reach the medium and above level.P content was very deficient,most of the AP in each soil layer was at a relatively low level,and a few of region were extremely deficient.K content was abundant,and increased with the deepening of soil layer,AK which could be used by plants were at a rich level only in a few areas,and most at a deficient level.AS was basically at the same level as that in farmland soil in the same area,EMg was low,and ECa was very lacking.The content of trace elements was basically at the same level or slightly higher than that in farmland soil in the same area.The soil nutrients showed obvious “surface aggregation” under the influence of biological enrichment process,soil fertility level in most areas were medium fertile,and a few were poor,the soil nutrient content showed a decreasing trend with the increase of altitude.