Nature slope and sea level elevation are two important intrinsic environmental factors of land resource which have some direct effects on the use and productive forces of land.
坡度和高程是土地资源固有的二个重要环境因子，对土地利用和土地生产力有直接作用。
2
The quenching mechanism of DNAF on intrinsic fluorescence quenching of protein and the types of interaction forces were proposed.