临安市不同山核桃产区土壤肥力状况的差异性研究

为探讨山核桃Carya cathayensis林地土壤基本肥力特征及土壤肥料管理对策，于2013年3-4月，采用全球定位系统（GPS）野外定位并采集浙江省临安市山核桃主产区7个乡镇共189个土壤样品，对临安市山核桃主产区土壤肥力状况进行分析和比较。结果表明:研究区土壤pH值变幅为pH 4.2~7.5，平均值为pH 5.2，小于pH 5.5的区域占75%；土壤有机质平均为31.6 g·kg-1，普遍较高，但也有12%的林地土壤有机质低于20.0 g·kg-1；大多数林地土壤有效氮较高，超过80.0 mg·kg-1的占91%，处于高水平（>200.0 mg·kg-1）的占15%；研究区山核桃林地土壤有效磷平均为14.0 mg·kg-1，但变幅大，分别有63%和40%的林地土壤有效磷低于10.0 mg·kg-1和5.0 mg·kg-1，土壤有效磷有待提高；土壤速效钾平均为85.9 mg·kg-1，51%的林地土壤速效钾质量分数不足80.0 mg·kg-1。各地需要根据实际情况，调整施肥数量和结构及开展土壤酸性改良，因地制宜地制定区域施肥规划。表7参23

Soil fertility in Carya cathayensis orchards for major towns of Lin'an City,China

To study soil fertility in Chinese hickory (Carya cathayensis) orchards via soil surveys and to optimize regional soil and fertilization management, in the spring of 2013, 189 soil samples were collected by GPS from seven towns in Lin'an, Zhejiang Province, China, where distribution of Chinese hickory is most widespread. Soil fertility properties were analyzed and compared among the towns. Results of the study area showed that soil pH value varied from 4.2 to 7.5 with a mean of 5.2; 75% of these soils had a pH <5.5. The content of soil organic matter (SOM) was rich in general with a mean of 31.6 g·kg-1. In most of the orchard soils, available nitrogen (SAN) (hydrolytic N) was rich:91% of the investigated soils >80.0 mg·kg-1 and 15% of those >200.0 mg·kg-1. In Tuankou Town all soils had SAN >100.0 mg·kg-1. Although the mean soil available phosphorus (SAP) was 14.0 mg·kg-1, 63% of orchard soils were <10.0 mg·kg-1 and 40% were <5.0 mg·kg-1. Mean soil available potassium (SAK) was 85.9 mg·kg-1, however 51% of the research area had SAK <80.0 mg·kg-1 implying a low SAK supply. Therefore, severe soil acidification and high SAN were most common in the research area and a considerable number of the orchard soils had low SAP and especially low SAK. Soil fertility management measures need to be made according to local soil conditions to ameliorate soil acidity and optimize fertilization; and soil testing and formulating regional fertilizer applications are required to control N fertilizer application, to improve soil P availability, and to emphasize K fertilizer application.Ch, 7 tab. 23 ref.]