Effects of artificial grassland type on soil water content of degraded land restored by ecological measures in suburban Beijing

Establishment of artificial grasslands is an effective and economic measurement for restoring degraded land, however, established grasslands consume soil water and disturb local water balance as well. To quantify the influence of artificial grasslands on soil water content, we monitored soil volumetric water content (VWC) at depths of 5 cm, 10 cm, 15 cm, 20 cm and 25 cm in artificial grasslands of Bromus inermis Leyss and Medicago sativa continuously throughout 2018. For Bromus inermis Leyss grassland, VWC peaked at depth of 20 cm (0.190±0.053 m3m−3) and varied little among the rest depths, while for Medicago sativa grassland, VWC increased with depth and the highest value was 0.153±0.047 m3m−3 at depth of 25 cm. Moreover, VWC in Bromus inermis Leyss grassland was obviously higher than that in Medicago sativa grassland for the whole year at depths of 5 cm, 15 cm and 20 cm, and slightly higher for part of the year at depth of 10 cm, but insignificantly lower at depth of 25 cm. As for water conservation, Bromus inermis Leyss grassland could perform better than Medicago sativa grassland. Under the identical climatic and edaphic conditions, the dramatic differences in VWC between grasslands of Bromus inermis Leyss and Medicago sativa imply that ecohydrological response should be taken into consideration, when selecting measures for ecological restoration.