The influence of poplar-crop intercropping on crop nutrient compositions

A small spacing，for example 10m，will lead to crop nutrient compositions debasement(including starch，fats and protein)，in which fats contents of wheat and peanut decrease 4．0％ and 2．5％ as well as the proteins contents are 8．4％ and 2．1％ ，respectively．However，a reasonable spacing，for example 30m，will improve crop nutrient compositions，in which fats contents of wheat and maize increase 9．6％ and 11．3％ ，respectively．It also demonstrates that the indexes of the crop nutrient compositions between rows have the same law in either mature stand or young growth．The content indexes of starch and fats are higher at the middle of rows but lower near the tree base，while the protein is quite the contrary．Among the studied spacing(10～30m)，the crop nutrient composition in the middle scope of rows is better than the control，but it is worse near the tree base．