Coupled variations of soil temperature and moisture in reclaimed fields filled with coal gangue of different grain size distributions

摘要

Purpose This study was aimed at investigating the effects of different reclamation modes on coupled variations of soil temperature and moisture. Materials and methods An experimental field was established, which consists of three plots (plots I, II, and III) filled with coal gangue of different grain size distributions (coarse grain, middle-coarse grain, and fine grain) and covered with the same thickness (50 cm) of soil. Temperature and moisture at four depths (10, 25, 50, and 65 cm) in three plots were monitored and analyzed. Results and discussion The study reveals that both in winter and summer soil temperature at each depth was highest in plot III and lowest in plot I. Although plot III performed better in heat preservation in winter, soil temperature of which was too high in summer for crop growth. The results also indicate that annual average of soil moisture at the depth of 10 cm and 25 cm was highest in plot II, namely plot II performed best in water holding in the tillage layer for the whole year. Conclusions Soil temperature and moisture in plot II were more conducive to crop growth on the whole, and it is recommended to adopt the reclamation mode of plot II for land reclamation in coal mining subsidence areas with high ground water table.