金沙江干热河谷土壤种子库植被恢复潜力研究

Study on Soil Seed Bank Vegetation Restoration in Jinsha River Dry-hot Valley

通过小支撑多样点选择研究样地、深层次土壤取样和幼苗萌发法等试验方案,探讨了金沙江干热河谷区云南东川野鸭塘小流域土壤种子库植被恢复潜力,研究表明:在0～40 cm深层次土层中,不同土地类型土壤种子库种子萌发潜力大小依次是沟道、荒草地、林地、灌木地.随着土壤层次深度的增加,不同土地类型土壤种子库萌发潜力差异显著,林地、沟道土壤种子库萌发潜力表现为表聚特征,萌发种子主要集中在0～5 cm的表土层;灌木地土壤种子库萌发的种子比较均匀地分布在0～40 cm土层中,表现为明显的均匀化特征;荒草地土壤种子库萌发的种子在0～5 cm表土层相对较少,主要集中在5 cm以下的土层中,种子下聚特征突出.在20～40 cm深层次土层中种子萌发潜力表现为荒草地最大,灌木地、沟道次之,林地最小.

Basing on such testing schemes as small supporting,multifold sampling points,deep soil sampling and seedling germination method,this paper discussed the recovery potential of the soil seed bank in Ye Yatang small watershed in Dongchuan,Yunnan Province of the dry-hot valley of Jinsha River.The analysis results indicate that in the 0～40 cm depth of soil layer in different land-used types,the seed germination potential of soil seed bank successively is gully channelmeadowwoodlandshrub land.With the increase in the depth of soil layers,the seed germination potential of soil seed bank is significant different in different land-used types.From the surface aggregation of the seed germination potential of soil seed bank in woodland and gully channel,germinating seeds are concentrated in the 0～5 cm depth below the surface of soil layer;The germinating seeds of soil seed bank in shrub land distribute uniformly in the 0～40 cm depth of soil layers,which has the significant uniformity characteristic;The germinating seeds of soil seed bank in meadow are concentrated to distribute below 5cm depth of soil layers,while only a small amount of seeds distribute in the 0～5 cm depth of soil layers relatively,which has the characteristic of undersurface aggregation;In the 20～40 cm depth of soil layers,the germination potential of meadow is maximal,shrub land＇s and gully channel＇s followed by orderly,woodland＇s is minimal.