Abstract: The study on 13 characters of cones and seeds of 6 Larix chinensis populations in Qinglin Mountain showed that there were significant differences in and among the populations.Except seed width and seed scale width,the other 11 characters were significantly different among populations. The variation coefficients of seed scale length,seed scale width,ratio of scale length to width,seed wing length,and seed wing width were larger among populations than in populations,while those of the other 8 characters were in adverse.Altitude had an obvious influence on the characters of cones and seeds,among which,seed width,scale width,scale length,seed wing length width,scale width,cone width,cone width,and the number of scales had a negative correlation with altitude,the ratio of scale length to width negatively correlated to slope,and scale width positively correlated to annual precipitation.The ratio of seed length to width and that of seed wing length to width showed a negative correlation to altitude.

Key words: Plastic film mulching, Soil microbial biomass carbon, Spring wheat, Plant nutrition, Soil quality, Semi-arid Loess Plateau