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Organic fertilization, a critical agronomic practice for improving nutrient availability and crop growth, may increase the risk of phosphorus (P) loss. To investigate the effect of organic fertilization on P availability, crop growth and P loss, a paddy field experiment was conducted in the saline-alkaline paddy soil. We designed four treatments: CK (no fertilizer), NPK (mineral fertilizer), and NPKC1 and NPKC2 (mineral fertilizer with low and high levels of organic fertilizer, respectively); the amounts of N, P2O5, and K2O were equal in the NPK, NPKC1, and NPKC2 treatments. Compared with the NPK treatment, organic fertilization enhanced the content of total, organic, and available P in the topsoil. Moreover, organic fertilization significantly improved both the growth and P removal of crops. The content of oxalate Fe, Al, and dissolved organic carbon, the main carriers of P loss, in the soil was the highest in the NPKC2 treatment. The soil P saturation ratio (PSR) in the NPKC2 treatment was 0.25, exceeding the threshold PSR for P loss of 0.16. Therefore, organic fertilizer application could improve P availability and crop growth; however, high-level organic fertilization increases the risk of P loss in coastal saline-alkaline paddy soils. [ABSTRACT FROM AUTHOR]

The bindings of organic matter (OM) with iron (Fe-OM complexes) are important for soil carbon (C) sequestration. Our objective was to evaluate the role of laccase in the formation of Fe-OM complexes in a coastal saline paddy soil. The experiment included two factors: (1) two nitrogen (N) levels, 255 (N1) and 400 (N2) kg N ha−1; (2) three straw levels: 0 (S0), 4500 (S1) and 9000 (S2) kg C ha−1. The results showed that the combined application of straw and N fertilizer increased the content of Fe-bound OC and laccase activity, both of which were the highest in N1S1 treatment, which was 7.48% and 0.58 μmol g−1 h−1, respectively. The content of Fe-bound OC was positively correlated with laccase activity, Feam content and soil moisture content, but negatively correlated with pH. Both Fe-bound OC and laccase activity were positively correlated with aliphatic functional groups and hydroxyl or amidogen, while both were negatively correlated with aromatic functional groups. Therefore, laccase might promote the formation of Fe-bound OC by changing the chemical structure of OC. In addition, the combined application of straw and N fertilizer could change laccase activity by changing microbial community structure (e.g. Chloroflexi, Ascomycetes and Zygomycota). [ABSTRACT FROM AUTHOR]

Organic amendments could improve soil nitrogen (N) availability and transformation characteristics, which decreases the N loss within soil profile induced by N excessive application. A field experiment was designed in Shiqiang village with different organic amendments in 2018: (i) control (CK); (ii) chemical fertilizer (NPK); (iii) 1200 kg C ha−1 plus NPK (NPKM) and (iv) 40 kg humic acid ha−1 plus NPK (NPKH). Compared with NPK treatment, in 0–30 cm soil, NH4+-N content in NPKM and NPKH treatments was increased by 9.15% and 13.36% and NO3– N content was increased by 11.44% and 12.85%, respectively, while in 30–60 cm soil, NO3– N content in NPKM and NPKH treatments was decreased by 13.51% and 8.54%, because organic amendments inhibited N leaching to deeper soil. Soil urease and invertase activity in NPKH treatment was 9.52% and 8.31% higher than that in NPK treatment, which was decreased with the decreasing soil depth. The grain yield was increased by 14.17% and 23.87% in NPKM and NPKH treatments, respectively. Thus, humic acid fertilizer was better in increasing wheat yield by improving N transformation and enzyme activities, which could increase wheat N uptake and inhibit N loss in North China Plain. [ABSTRACT FROM AUTHOR]

The establishment of high-yielding agricultural production systems is severely restricted by low soil organic carbon (SOC) and high Na+ concentration in saline-alkaline soils. In order to confirm the effects of biochar and phosphorus (P) fertilization on SOC sequestration, soil physical structure and inorganic P (Pi) fractions, as well as optimize the amount of P fertilizer, a field experiment was designed with two factors: with biochar at 0 (C0), 1% (C1) and 3% (C2); with P at 0 (P0), 64 (P1) and 128 kg ha−1 (P2). The results indicated that biochar input enhanced SOC, however, the effect of P application on SOC and soil physical structure were negligible. Compared to C0, SOC was increased by 98–113% for C1 and 180–195% for C2. Due to the SOC enhancement and reduction of soil Na+ concentration, biochar input decreased ρb, increased MWD and WSMA. For Pi fractions, soil Olsen-P, Ca2-P, Ca8-P, Fe-P and Al-P were increased, mainly due to the direct supply, retention and the improvement of biological availability. Overall, C2P1 was the most efficiency treatment to enhance SOC, improve soil physical structure, and C2P2 avail to increase the supply capacity of soil P, but had no significant difference with that in C2P1. [ABSTRACT FROM AUTHOR]

China's plan to establish a social credit system (SCS) has aroused the concern of building a surveillance state. Yet this view oversimplifies and misunderstands the essence of the SCS. The highest priorities of the SCS are promoting economic credibility and reinforcing court orders. Meanwhile, the SCS aims to steer citizens' social behaviors and interactions by utilizing a redlist system that introduces numerous moderate rewards. The SCS is also more lax in execution than in planning. It reflects a unique Chinese understanding of law, which treats law as a moral guide. This article also acknowledges the concerns for the SCS. Without actively preventing positive and negative invasions in the construction of the project, the SCS authorities will risk creating further mistrust in society. [ABSTRACT FROM AUTHOR]

Empowered by the media, legislations in China have, over recent years, been increasingly influenced by public focusing events. Many national legislations have been triggered by public focusing events, rather than being entirely pre-determined by the Party or by the government. After a detailed empirical study of 132 public focusing events and national legislations between 2003 and 2016, the article explores the features, the reasons, and the advantages and disadvantages of legislations triggered by public focusing events. In these 'pressure-induced legislations', the public focusing events serve as catalysts that create a new consensus or demand for new laws and regulations that are enacted over a short period of time, thereby influencing the national legislation. Compared to traditional Chinese legislations, pressure-induced legislations are more efficient and more responsive to the needs of the general public, but they also carry the danger of irrational judgments being made, leading to the enactment of improper laws or regulations. [ABSTRACT FROM AUTHOR]

To understand the mechanisms behind the beneficial combinations of the existence and formation processes of tripartite symbiosis of arbuscular mycorrhizal fungi (AMF) and nitrogen (N)-fixing rhizobia in phosphorus (P) deficiency. The effects of different inoculations ofBradyrhizobium japonicum(BJ) andGlomus mosseae(GM) on plant growth, P uptake, and soluble sugar concentration of soybeans in a P-deficient environment were investigated utilizing split-root systems supplemented with either KH2PO4(0.01 mM, I-P) or Phytin (200 mg P kg−1, O-P) for 56 days. Six treatments were applied: (1) mono-inoculation of BJ in organic P compartment, O-BJ; (2) mono-inoculation of BJ in inorganic P compartment, I-BJ; (3) mono-inoculation of BJ in organic P compartment and mono-inoculation of GM in inorganic P compartment, O-BJ/I-GM; (4) mono-inoculation of BJ in inorganic P compartment and mono-inoculation of GM in organic P compartment, O-GM/I-BJ; (5) dual inoculation of BJ and GM in organic P compartment, O-BJ/GM; and (6) dual inoculation of BJ and GM in inorganic P compartment, I-BJ/GM. Compared with sole inoculation of BJ, dual inoculation increased the plant and nodule biomass, which were higher in I-BJ/GM and O-BJ/I-GM treatments compared to O-GM/I-BJ and O-BJ/GM treatments. Roots inoculated with GM in I-P grew better regardless of whether BJ was inoculated or not. GM inoculation in I-P also increased the number of leaves and the rate of photosynthesis. Nodule P concentration following dual inoculation in I-P was increased 2.1-fold compared to that in sole inoculation with BJ. Shoot soluble sugar concentration with dual inoculation in O-P was less than that in the other three treatments. Inoculated with GM in I-P increased the root soluble sugar concentration compared with the non-GM plants or GM inoculation in O-P. The present findings may explain a regulatory system for the nutrition of beneficial microbial interactions by the nodule or by AM fungal hyphae at selecting the best performing tripartite symbiotic partners in P deficiency. [ABSTRACT FROM PUBLISHER]

A new sensitive metalloimmunoassay using antibody labeled with metal-organic frameworks (MOFs) nanoparticles (NPs) for indirect but amplified chemiluminescence (CL) was developed for the detection of alpha-fetoprotein (AFP) in human serum. Fe-MIL-88B-NH2NPs was prepared with a microwave-assisted synthesis approach in a facile manner, with NPs size of 50 ± 5 nm in length and 30 ± 5 nm in width. To accomplish the immunoassay of AFP, Fe-MIL-88B-NH2NPs labeled anti-AFP was eventually dissolved in hydrochloric acid after binding with AFP for indirectly amplified signal through detection of Fe3+by a luminol-H2O2CL method. High selectivity from the immunoreaction and high sensitivity from the amplified CL were obtained for the proposed method, with a limit of detection (3 pg mL−1) better than those of AFP immunoassays using other methods and labeling agents including Fe-based NPs for other similar analytes. Human serum samples were analyzed for AFP by this method, with the analytical results in good agreement with those obtained by the enzyme-linked immunosorbent assay. [ABSTRACT FROM PUBLISHER]

Astragalus galactites is a medicinal plant. The total plastome length of A. galactites is 126,117 bp. It contains a large single-copy region of 69,805 bp, two inverted repeat regions of 20,638 bp, and a small single-copy region of 15,036 bp. The cp genome contains 110 complete genes, including 75 protein-coding genes (75 PCGs), 4 ribosomal RNA genes (4 rRNAs), and 30 tRNA genes (30 tRNAs). The overall GC content of cp DNA is 33.9%, the corresponding values of the LSC, SSC, and IR regions are 33.0%, 30.4%, and 43.3% respectively. The phylogenetic tree shows that A. galactites has the closest relationship with A. laxmannii. [ABSTRACT FROM AUTHOR]

A pot experiment was conducted to investigate the organic phosphorus (P) (phytate) utilization of Zea mays L. with different nitrogen (N) forms (NH4+ and NO3-) when both arbuscular mycorrhizal (AM) fungus (Funelliformis mosseae) and phosphate-solubilizing bacterium (PSB, Pseudomonas alcaligenes) are present. The soil was supplied with either KNO3 or (NH4)2SO4 (200 mg kg-1 ) with or without phytin (75 mg P kg-1). Results showed that the application of NH4+ to the soil in a plant-AM fungus-PSB system decreased rhizosphere pH and increased phosphatase activity. It also enhanced the mineralization rate of phytin, which resulted in the release of more inorganic P. The application of NO3- promoted mycorrhizal colonization and hyphal length density in the soil. The inorganic P in the hyphosphere decreased, but more P was transferred to the plant through the mycorrhizal hyphae. Hence, in addition, the application of the two different N forms did not significantly alter the content of plant P. The plant supplied with different N fertilizers acquired P through different mechanisms associated with other microbes. NH4+ application promoted phytin mineralization by decreasing soil pH, whereas NO3- application increased inorganic P uptake by strengthening the mycorrhizal pathway. [ABSTRACT FROM AUTHOR]