Publications by authors named "Songjuan Gao"

In southern China, winter green manure is widely used in rice cropping systems for improving grain yields and soil fertility. Cd pollution has recently been reported in some of these paddy fields. Research on the in-depth understanding of how green manuring affects Cd absorption in rice is limited.

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Fertilizers are widely used to produce more food, inevitably altering the diversity and composition of soil organisms. The role of soil biodiversity in controlling multiple ecosystem services remains unclear, especially after decades of fertilization. Here, we assess the contribution of the soil functionalities of carbon (C), nitrogen (N), and phosphorus (P) cycling to crop production and explore how soil organisms control these functionalities in a 33-year field fertilization experiment.

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Milk vetch (Astragalus sinicus L.) is leguminous green manure (GM) which produces organic nitrogen (N) for subsequent crops and is widely planted and utilized to simultaneously reduce the use of synthetic N fertilizer and its environmental costs in rice systems. Determination of an optimal N application rate specific to the GM-rice system is challenging because of the large temporal and spatial variations in soil, climate, and field management conditions.

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Biological nitrogen (N) fixation (BNF) via diazotrophs is an important ecological process for the conversion of atmospheric N to biologically available N. Although soil diazotrophs play a dominant role in BNF and arbuscular mycorrhizal fungi (AMF) serve as helpers to favor BNF, the response of soil BNF and diazotrophic communities to different long-term fertilizations and the role of AMF in diazotrophs-driven BNF are poorly understood. Herein, a 33-year fertilization experiment in a wheat-maize intercropping system was conducted to investigate the changes in soil BNF rates, diazotrophic and AMF communities, and their interactions after long-term representative fertilization (chemical fertilizer, cow manure, wheat straw, and green manure).

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Soil cadmium (Cd) contamination is becoming a widespread concern because of its threat to global ecosystem health and food security. Co-incorporation of Chinese milk vetch (MV) and rice straw (RS) is a common agricultural practice in Southern China; however, the effects of combining these two materials with biochar on Cd bioavailability remain unclear. This study investigated the effects of MV, RS, rape straw biochar (RB), iron-modified biochar (FB), and their combinations on Cd uptake by rice through incubation and field experiments.

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The legume species (Chinese milk vetch [CMV]) has been widely cultivated for centuries in southern China as one of the most important green manures/cover crops for improving rice productivity and preventing soil degeneration. In this study, we generated the first chromosome-scale reference genome of CMV by combining PacBio and Illumina sequencing with high-throughput chromatin conformation capture (Hi-C) technology. The CMV genome was 595.

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The danger posed by cadmium (Cd) pollution to rice production is continuously increasing. Co-utilizing milk vetch (Astragalus sinicus L.) and rice straw is a good practice for rice yield and soil fertility in south China.

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The co-incorporation of rice straw (RS) and milk vetch (MV) into paddy fields has been increasingly applied as a sustainable farming practice in southern China. Our previous study revealed the contribution of bacteria to the co-decomposition of the RS and MV mixture, although additional underlying factors driving the co-decomposition process need to be clarified. The present study further determined the succession of fungal communities and enzyme activity in the co-decomposition process of the RS and MV mixture.

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The present study determined the dynamic changes of enzyme activity and bacterial community in rice straw (RS) and milk vetch (MV) co-decomposing process. Results showed that mixing RS and MV promoted decomposition. The mixture enhanced β-glucosidase and β-cellobiohydrolase activities relative to its monospecific residue during the mid-late stage of decomposition.

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Water-extractable organic matter (WEOM) plays an important role in many chemical processes and in soil organic matter accumulation. Large amounts of WEOM can be released by green manure when being incorporated into the soil. However, the characteristics of WEOM extracted from different green manures (GMs) are unclear.

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Soil dissolved organic matter (DOM) plays an important role in the biogeochemistry of carbon, nitrogen, and phosphorus and in the transport of heavy metals and pesticides in soil. In moisture soil, green manures and soils were sampled in situ at the ploughed stage of green manures. A 56-day laboratory incubation experiment was conducted to simulate the dynamic changes of soil DOM influenced by the decomposition of green manures, the green manures were Hairy vetch (Vicia villosa Roth.

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Phosphorus (P) deficiency is a severe challenge in many agricultural areas around the globe, while at the same time, aquatic environments are threatened by leaching and runoff of excess P in other areas. Accurate, cheap, and rapid assessment of crop P needs and risk of P loss is therefore necessary to optimize the use of P fertilizer worldwide. The purpose of this study was to develop a method to predict soil P concentrations by visual and near-infrared spectroscopy using reference P concentrations determined by diffusive gradients in thin films (DGT); Olsen P results were included for comparison.

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Article Synopsis
  • The study investigated the effects of long-term fertilization on dissolved organic matter (DOM) in irrigation-desert soil in northwestern China, analyzing data from an experiment begun in 1988 with four treatments: organic fertilizer (OF), green manure (GM), chemical fertilizer (CF), and a control (CK).
  • Results showed that all fertilization treatments significantly increased dissolved organic carbon (DOC), dissolved nitrogen (DON), total carbohydrates (TCs), and total organic acids (TOAs) compared to CK, with organic fertilizer yielding the highest increases across all metrics.
  • Ultraviolet-visible spectrometry revealed that fertilization enhanced the stability and complexity of DOM, showing greater aromatic and hydrophobic characteristics, particularly in the OF treatment,
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The February orchid (Orychophragmus violaceus)-spring maize rotation system is established to resolve the problems caused by the expansion of fallow fields in North China. Based on a site-specific experiment, temporal and spatial variations of soil NO(3-)-N were investigated during the period from February orchid incorporation to maize harvest. The results showed that the nitrate content in soil profiles not only showed a temporal characteristic, i.

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