滇池流域土壤脲酶活性的空间差异性研究

The Characteristics of Spatial Distribution of Soil Urease Activities in Dianchi Lake Watershed

摘要: 选取滇池流域呈贡县斗南镇、晋宁县上蒜镇、盘龙区松花坝、高新区马金铺四个区域的土壤为研究对象，通过苯酚–次氯酸钠比色法，测定不同区域采样点土壤脲酶活性。结果表明，滇池流域土壤脲酶活性总体变化范围为：5.30-28.70 mg/kg∙h⁻¹，不同区域、不同地形的土壤脲酶活性差异显著。四地区土壤脲酶活性平均值分别为：呈贡地区17.1 mg/kg∙h⁻¹，高新区12.41 mg/kg∙h⁻¹，盘龙区11.66 mg/kg∙h⁻¹，晋宁区9.5 mg/kg∙h⁻¹，其土壤脲酶活性高低顺序为：呈贡县 > 高新区 > 盘龙区 > 晋宁县。研究发现，土壤有机质含量越高，其土壤脲酶活性越高；滇池流域不同土地利用方式土壤脲酶活性空间分布特征为：坝平地 > 坡耕地 > 林地。该文为土壤脲酶活性作为判断滇池流域不同区域不同土地利用方式的土壤肥力指标提供数据支持和科学依据。

Abstract:  In this paper, the soils were collected from Dounan town in Chenggong county, Shangsuan town in Jinning county, Songhuadam in Panlong district and Ma Jinpu in high-tech district as the objects of study. This research surveyed and evaluated soil urease activity of different sampling points and different regions by phenol-sodium hypochlorite colorimetric and made focuses on analyzing the directional distribution cha- racteristics of soil urease activities in Dianchi lake watershed. Results were as follows: overall variation range of the soil urease activity in Dianchi lake watershed was: 5.30 - 28.70 mg/kg·h⁻¹, different regions and different terrain have significant effect on soil urease activity. The sequence of soil urease activity level of these four areas inDianchiLakewatershed is Chenggong county > high-tech district > Panlong district > Jinning county; and the average soil ureases of these four areas are 17.1 mg/kg·h⁻¹, 12.41 mg/kg·h⁻¹, 11.66 mg/kg·h⁻¹ and 9.5 mg/kg·h⁻¹, respectively. In addition, due to the dig difference of vegetation coverage on different terrain soil, root system, the content of soil organic matter and soil physical and chemical properties, the directional distribution characteristics of soil urease activity of different terrain in Dianchi lake watershed was: dam flat ground > sloping cultivated land > woodland.