Soil samples of cultivatedhorizon from Gongpeng town were analyzed in 1998 and the results were compared with that in 1990.
1998年对黑土区(弓棚镇)的耕层土壤养分进行分析，并与1990年该区土壤的化验结果进行了比较。
2
Therefore, "wave type" section cultivatedhorizon may occur drier phenomenon much easier than "flat type" section. This may be the main reason why drier phenomena easily happen in the black soil.