To investigate the effects of nitrate (NO3-), ammonium (NH4+) and themixture of NO3-and NH4+ on photosynthesis of wheat ......

磷的吸收和利用效率对植物生长和产量尤为重要.然而,在不同氮形态下,雌雄异株植物对土壤磷的吸收和利用策略尚不清楚.本论文研究了......

　　Landfills implemented with onsite leachate recirculation can efficiently remove pollutants,but currently they are re......

为探究吕家坨井田地质构造格局,根据钻孔勘探资料,采用分形理论和趋势面分析方法,研究了井田7......