Cultivated land sustainable use evaluation based on niche-fitness Niche-Fitness Model into Multi-Suitability Evaluation of Economic Forest Based on GIS in Poyang Lake Region Contrastive analysis in space and on time of urban ecosystem niche-fitness Analysis on water utility of artificial sand fixing plants and its numerical simulation of the procedure of niche fitness in Shapotou Area The effect of water-fertilizer conditions on crop‘‘‘‘s niche-fitness and yield in semi-arid regions of the Loess Plateau