%A LIU Yue-Hua, CHEN Yuan-Quan, ZHU Min, QU Bo, SHUI Peng, GAO Wang-Sheng %T Relationship between Crop Productivity and Ecological Factors in Poplar-Crop Intercropping Systems in Haihe Lowland Area %0 Journal Article %D 2010 %J Acta Agronomica Sinica %R 10.3724/SP.J.1006.2010.01355 %P 1355-1361 %V 36 %N 08 %U {https://zwxb.chinacrops.org/CN/abstract/article_4602.shtml} %8 2010-08-12 %X Agroforestry system is an approach to improve land use efficiency, it not only allows for the production of trees and crops, but also makes highly use efficiency of natural resources. Because of its advantages of Agroforestry, large scales of poplar-based Agroforestry systems have been developed in north of China since 2002. Hengshui area, in Hebei province, where lots of poplar-based Agroforestry systems exist, is a typical area lacking in water. Our previous study showed that Agroforestry systems consumed a large quantity of water storing in soil and decreased the production of both trees and underlayer crops as trees grew. To analyze the relationships of crop biomass with 0–40 cm soil moisture, and photosynthetically active radiation (PAR) and temperature, we conducted a study from Oct. 2007 to Oct. 2009 on 6–7 year-old poplar-crop intercropping systems with three different patterns of poplar plantations. Compared with sole crop system, PAR and 0–40 cm soil moisture in Agroforestry systems were reduced by 34.43%–76.71% and 18.67%–42.74% respectively. Crop biomass, PAR and soil moisture all showed significant difference among different Agroforestry systems (P<0.05). Ryegrass biomass was highly correlated with PAR, while soybean biomass was highly correlated with both PAR and soil moisture (P<0.05), with all the correlation coefficients 0.7500 (P<0.05) in both 2008 and 2009. The results showed that Agroforestry systems could product more crop biomass by increasing either PAR or soil moisture. And increasing PAR by removing poplar trees (removing alternate trees in rows, or even removing alternate tree rows) or tree branch pruning was an effective measure under the condition of seriously lacking in water in that area.