The yield-increasing and slowly releasing effects of palygorskite coated fertilizer were investigated with pot experiment.The result showed that application of diammonium phosphate coated with palygorskite at 225 kg·hm-2,the effective siliquae and yield of rape(Brussica napus) increased by 2.27 % and 255.33 % respectively compared with control.The biomass of wheat which planted after rape increased by 57.67 % when compared with control at 300 kg·hm-2.The content of chlorophyll,protein and soluble sugar in rape at latter growth stage were higher than that of the control,while MDA content was lower.It is suggested that palygorskite coated fertilizer shows good anti-aging and adverse-resistance characteristics,it also has certain slow release property on diammonium phosphate.

This paper carried out pot experiment of palygorskite coated urea on the impact of spring wheat yield and aftereffect,evaluated its ecological significance for the scientific issues with improving the fertilizer utilization factor.The results showed that palygorskite coated urea could effectively improve the economic yield,biomass yield,economic coefficient,thousand grain weight and grain number per ear of spring wheat,increase yield and fertilizer utilization fator of it,raised fertilizer aftereffects.Therefore,it suggested that palygorskite could be used as a slowly-releasing fertilizer coating material to apply in practice,which had ecological significance in a certain.

Spring wheat pot experiments were used to study the slow release effect and mechanism of palygorskite coated fertilizer. The results show that palygorskite coated phosphorus helps to make a slow release of fertilizer, to increase the weight per 1 000 grains, the economic coefficients, the economic yield, and the biomass of spring wheat, and to promote the transformation of biochemistry matter in spring wheat and the delayed aging. Therefore, palygorskite can be used as a new type of slow -release fertilizer coating materials in production.

The factors causing grassland in Maqu County of Gansu Province were analyzed and it could be concluded that both natural factors and human factors were the crucial issues.The overgrazing and rodent/pest damage were very severe after degradation.It was suggested that the stocking rate should be determined on the base of carrying capacity and the enclosure,re-seeding and rodent/pest control should be carried out in order to control the grassland degradation.