摘要
安徽省十三个土类1006个耕层土壤的有效钼含量和分布研究表明:88%的耕层土壤,其有效钼在临界值0.15ppm以下,均值0.07ppm。土类中有效钼平均含量最高和最低分别是石灰土(0.141)和砂姜黑土(0.043),耕层土壤钼值在6.2以下的占48%,各自然地理区有效钼极低水平(<0.1ppm)分布频率,在江淮丘陵、皖南山区、皖西地区、淮北平原、沿江平原分别占该地区的70、56、78、87、和60%。有效钼在土壤剖面中以表层富集和下层淀积两种类型为主。pH<7的土壤有效钼含量与土壤有效B、Mn、Cu、Zn和Fe之间呈显著或极显著的直线正相关;pH≥7的土壤有效钼仅与有效Cu和Fe之间有极显著的直线正相关。
Soil available Mo of 1400 samples from 14 soil types of Anhui province were detected through the Tamm′s solution extraction——Oscillpolargram method. Results inform.1、88% of the total samples from plough layer present an available Me content below the critical limitation of 0.15 ppm, indicating that the Mo contents of 885 samples average 0.07 ppm and of 121 samples, 0.255 ppm, resulting in 1.18×10~8 and 1.57×10~7 mu below and above 0.15ppm, respectively.2、Available Mo content varies greatly among soil types, soils derived from individual Parent materials, and soils scattered in different geographical regions. Limestone soil averagely shows the highest Mo content (0.141ppm), while Shajiang meadow soil shows the iowest(0.043 ppm). Soils derived from silica shale, lake sediments, and river alluvial contain significantly higher Me, with means at 0.176, 0.157, and 0.138 ppm, respectively. Those from Huanghe deposits and loess deposited in ancient lakes contain apparently low availalle Me, far lower than 0.1 Ppm. In east and south Anhui, soil available Me contents are 0.104 and 0.107 ppm, respectively, for that in the north only 0.085 ppm.3、Correlations were commonly observed between Mo and B, Cu, Zn, and Fe for soils with PH lower than 7, at significance of 0.05, 0.01, and 0.001. Relationships were found 0nly in Mo——Cu and Mo——Fe for soils with PH>7.4、Ninety—five soil Profiles were categorized into 5 types in accordance with profiles—Mo—distribution, among which 24 show a Mo increase along with the soil dePth, other 24 show the opposite.
