Woody organic amendments for retaining soil water, improving soil properties and enhancing plant growth in desertified soils of Ningxia, China

Woodchip and biochar amendments differentially influence microbial responses, but do not enhance plant recovery in disturbed semiarid soils

“…However, the observed increase in soil efflux in the incorporated woodchip treatment combined with low plant growth not similarly observed in the surface treatment suggests that application location is a significant factor for biological processes. Similar results regarding the importance of amendment location on microbial responses have been observed in arid ecosystems (Biederman & Whisenant ; Li et al ). Further analysis is required to better understand which pool of soil C is being used by the microbial community and released from the soil, the woodchip C or preexisting soil C, as well as to better understand what this would mean for the long‐term consequences for soil C if the pattern of high soil efflux and low plant cover, reducing the plant‐pump of chemically diverse C into soil, continues.…”

“…Extracts were analyzed using a Shimadzu TOC‐5000A equipped with a total dissolved nitrogen module (Shimadzu Scientific Instruments, Inc., Columbia, MD, U.S.A.). The term DOC is commonly used to describe two distinct forms of dissolved organics: (1) the total water extractable organic carbon (WEOC) produced from laboratory extractions, or (2) the extant DOC existing in the liquid phase of a soil located in in situ macro and micropores also referred to as DOC (Li et al ). This overlap in usage of the term can create confusion and inhibit comparison of WEOC dynamics across studies.…”

Using woody organic matter amendments to increase water availability and jump‐start soil restoration of desertified grassland soils of Ningxia, China

“…The four different experimental treatments were created at the start of the experiment. The treatments, based on results from prior microcosm experiments (Li et al, ), were (a) no organic materials added to desertified soil (Control); (b) coarse wood chips, derived from poplar ( Populus alba ) , with average chip length of 1 cm, applied as a Mulch layer approximately 3–4 cm deep over the soil surface (Mulch); (c) coarse poplar wood chips incorporated by shovel into the top 20 cm of desertified soil at a concentration of 5% weight/weight (Wchip); and (d) ground chips incorporated, as in #3, plus an addition of a branch shelter consisting of a lattice of thin willow branches (no leaves; Salix sp .) criss‐crossed over the Wchip soil, approximately 30 cm in height and covering/shading ~50% of each plot's surface (Wchip + Br).…”

“…Woody amendments also have higher carbon to nitrogen/phosphorus ratios and lignin/tannin contents than herbaceous amendments, with different impacts on soil chemistry and microbes. We conducted a comprehensive microcosm experiment, which demonstrated that incorporating wood chips can improve the ability of degraded soil to capture and hold moisture (Li et al, ). Moreover, incorporated wood chips improved other physical properties and enhanced soil microbial biomass and enzyme activity.…”

Exploring soil amendment strategies with polyacrylamide to improve soil health and oat productivity in a dryland farming ecosystem: One‐time versus repeated annual application

“…Other soil amendments, for example, biochar, can be used for similar purposes in improving crop productivity, but the availability of biochar is limited in the study area. Li et al () suggested that an appropriate biochar application rate of around 30 t ha −1 (roughly 4,761 USD ha −1 ), which is nearly 70‐times the cost of a single application of PAM, and although appropriate for high‐value crops, it is unlikely viable for low‐value crops such as oat. On‐the‐other‐hand, biochar is stable and may only require a single application.…”