Beneficial effects of crab burrowing on the surface soil properties of newly formed mudflats in the Yellow River Delta

Up to now, few studies pay attention on the effects of crab burrowing on soil properties of newly formed mudflats. However, this information is important to protect and manage the new-formed area. Therefore, a field observation was carried out to investigate the effects of crab burrowing on soil properties of newly formed mudflats in the Yellow River Delta. Crab burrow parameters and soil properties were measured at three fixed locations. Results indicated that crab burrowing greatly affected soil texture, but not soil nutrient. Soil textural feature was changed from clay to silt by significantly increasing the proportion of sand (+3.82%) and decreasing the proportion of clay (-4.76%). Crab burrowing showed significantly negative effects on soil bulk density, pH, soil salinity, and proportion of clay (p < 0.05), but significantly positive effects on water content and the proportion of sand and silt (p < 0.05). During crab burrowing, soil total carbon, total nitrogen, and C/N ratio increased slightly, but there were no significant differences in the properties of soil samples with and without crab burrowing (p > 0.05). Overall, crab burrowing had distinct positive effects on surface soil properties, especially the soil texture. These results suggest that crab burrowing would improve surface soil conditions, which in turn would stimulate other life processes and promote the stability of newly formed wetlands. (C) 2019 European Regional Centre for Ecohydrology of the Polish Academy of Sciences. Published by Elsevier B.V. All rights reserved.