The ploughing-induced compaction of the interface between topsoil and subsoil negatively affects the connectivity and continuity of the complex pore system through plough pans as artificial boundary resulting in water-logged conditions. The conversion of arable land into hayfield is an opportunity for breaking up plough pans and recovering pore networks in the long-term. The basic idea of the current study was to investigate the potential pore structure recovery effect by growing either deep-rooting alfalfa or shallow-rooting grass on former conventionally-tilled cropland.
As an extension of a previous work (Chen and Han, 2015a), this study explored the arable land use of the world economy from source of exploitation to sink of final consumption via the global supply chain, by means of embodiment accounting that includes the indirect feedbacks associated with both intermediate and primary inputs. In magnitude, the global transfer of arable land use is estimated to be around 40% of the total direct exploitation. The connections as well as imbalances of major economies in intermediate and final trades of arable land use are discussed.
This study assessed the carbon (C) budget and the C stocks in major compartments of the soil food web (bacteria, fungi, protists, nematodes, meso- and macrofauna) in an arable field with/without litter addition. The C stocks in the food web were more than three times higher in topsoil (0–10 cm) compared to subsoil (>40 cm). Microorganisms contained over 95% of food web C, with similar contributions of bacteria and fungi in topsoil. Litter addition did not alter C pools of soil biota after one growing season, except for the increase of fungi and fungal feeding nematodes in the topsoil.
