Abstract: The developing process of Keerqin sandy land under the serious disturbances created byhuman activities was analysed according to historico-ecological point of view.Keerqin sandyland was an extensive grassland with dense pine forest patches in its eastern part only 800years ago,But now the pine forests almost disappeare and the most part of the grasslandhas become sandy land because its misusing.The area of sandy land condinues being expan-ded and the serious ecological disasterns have been brought.The best way of harnessing thesand land would be to make the population increase and the resource exploitation and envi-ronment protection be well coordinated.

Key words: mechanical transplanting, super japonica rice, yield, quality, N use efficiency.