net primary productivity (npp)造句

The spd model is made by the ins titute of geographical sciences and natural resources research of chinese academy of sciences . it combines social economic factors , such as city and transportation foundational facilities , with nature factors , for example the digital elevation model ( dem ) and net primary productivity ( npp ) of plants to simulate the spatial distribution of population density of china by the advanced grid generation technology
中国模拟人口密度模型是由中国科学院地理科学与资源研究所首先提出的，这个模型试图利用先进的格网生成技术，将城市、交通基础设施等社会经济因子和陆地数字高程( dem ) 、陆地植被净第一性生产力( npp )等自然因子相结合，通过模型的反演，模拟某一时期的中国人口密度空间分布状况。
It's difficult to find net primary productivity (npp) in a sentence. 用net primary productivity (npp)造句挺难的