Earthworm biomass and abundance, soil chemical and physical properties under different poplar plantations in the north of Iran

Abstract

We evaluated earthworm abundance and biomass in plantations of different poplar species and clones as well as the effect of some soil chemical and physical properties on them. Even-aged poplar species and clones, planted at Safrabasteh Poplar Research Station about 18 years ago in the north of Iran, included: Populus deltoides Bartr. cv. 69/55 (P. d. 69/55), Populus deltoides Bartr. cv. 63/51 (P. d. 63/51), Populus euramericana Guinier. cv. 45/51 (P. e. 45/51), Populus euramericana Guinier. triplo (P. e. triplo), and Populus caspica Born M. (P. caspica), as endemic and endangered poplar species, were selected in this study. Earthworm abundance and biomass, soil texture, bulk and particle density (BD, PD), pH, organic carbon (OC), total nitrogen (N), available phosphorus (P) and exchangeable potassium (K) were evaluated. The results showed that the earthworm abundance and biomass, OC, P and N in P. d. 63/51 were higher than in the other poplar species and clones. The correlation coefficients showed a positive correlation of OC, N and a negative correlation of pH, clay, BD and P with earthworm biomass. Based on the results, compared to the other species and clones P. d. 63/51 creates favourable conditions to produce more organic matter and higher abundance and biomass of earthworms, hence it could be beneficial for maintaining the soil quality status for successive plantings.

Keywords

• soil properties
• populus clones
• populus caspica
• organic carbon
• poplar