内蒙古典型草原主要土壤类型和植物硫状况的研究(英文)

SULPHUR STATUS OF SOILS AND PLANTS OF THE INNER MONGOLIA STEPPE

通过对内蒙古典型草原 4种主要土壤类型及 12 2种主要植物硫含量的分析 ,并与主要放牧家畜的营养需要相结合 ,综合评价了内蒙古典型草原硫的营养状况。研究表明 :4种主要土壤类型不同层次 (0 .2～ 0 .4m ,0 .1～0 .2 m和 0～ 0 .1m )的土壤中有机硫的含量变化很大 ,为 17～ 397μg· g- 1 ,有机硫的含量与土壤中有机碳和全氮含量呈高度正相关。土壤中平均无机硫含量低于 10μg· g- 1 ,但黑钙土土壤中无机硫的含量较高 ,达 2 0μg· g- 1 左右。土壤中微生物硫含量占土壤中全硫含量的 1.78%～ 2 .80 %。所测定的 12 2种主要植物中有 75 %的植物体内硫含量低于 0 .16 % ,氮 /硫比大于 14∶ 1;与主要放牧家畜的营养需要相比 ,有约 80 %的植物缺硫。植物体中硫的含量与土壤中有效硫的含量显著正相关。

The sulphur status of 4 soils and 122 common plants from Inner Mongolia steppe were determined and evaluation was made of the sulphur nutrition of grazing animals. The results showed the organic sulphur content ranged from 17 μg·g -1 in the 0 2 0 4 m soil layer to 397 μg·g -1 in the top soil. The mean sulphate S concentrations were less than 10 μg·g -1 ; while greater concentrations were found in only the chernozem soil. Biomass S accounted for 1 78% 2 80% of total S in 4 soils Seventy five percent of plant samples examined had less than 0 16% S, and more than 80% of them had a N∶S ratio greater than 14∶1. More than 80% of the plants were deficient in S. There was a close relationship between plant available soil sulphur and total plant sulphur concentrations. It was concluded that sulphur deficiency is widespread in the Inner Mongolia steppe and that sulphur fertilizer requirements should be evaluated.