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A heavy nocturnal warm sector rainfall occurred over the western coastal region of South China in June 2020, of which the precipitation magnitude was seriously underestimated by the operational TRAMS (Tropical Regional Atmosphere Model System) model. In this study, by improving the configuration of initial conditions (ICs) and lateral boundary conditions (LBCs) in offline nesting, the simulation of the convection initiation (CI) process can be well improved. The CI simulation is found to be sensitive to the vertical resolution in ICs in this case. When the low‐level vertical resolution of ICs is increased, the nocturnal near‐surface cold layer caused by inland mountains can be resolved better, which is necessary to form the convergence line along the coastline. Another important impact of increasing the vertical resolution of ICs is the successful simulation of horizontal convective rolls (HCRs) over the northern South China Sea. The HCRs apparently increase the depth of the warm‐moist marine boundary layer jet (MBLJ), and finally lead to the CI along the coastline. The increased vertical resolutions of LBCs can reduce the discontinuity of simulated moist tongue across the southern lateral boundary of the TRAMS model, which provides more moisture for the warm sector rainfall through MBLJ. LBCs with Higher temporal frequency help to alleviate the western position bias of rain belt by reducing the temporal interpolation error. Our study highlights the importance of finer ICs and LBCs in offline nesting for regional operational NWP systems in the South China region. Plain Language Summary: Warm‐sector heavy rainfall in South China usually develops under weakly forced weather condition, numerical forecasting of its initiation and intensification process is a difficult problem. To investigate its sensitivity to the configuration of initial conditions (ICs) and lateral boundary conditions (LBCs), a simulation study is carried out for a nocturnal warm sector rainfall event happened in western Guangdong. When the low‐level vertical resolution of ICs is increased, the nocturnal near surface cold layer from inland mountains can be resolved better. Another important impact of increasing vertical resolution of ICs is the successful simulation of horizontal convective rolls (HCRs) over the northern South China Sea. The HCRs apparently increase the depth of warm‐moist marine boundary layer jet (MBLJ), and finally lead to the CI along coast line. Additionally, the vertical resolution and the updating frequency of the lateral boundary conditions also have important effects on the simulation of the rainstorm intensification process. This paper emphasizes the importance of accurate ICs and LBCs to improve the predictability of warm‐sector rainfall in South China, which can provide practical reference for the design of operational systems. Key Points: Increasing low‐level vertical resolution of initial conditions is critical to the convection initiation (CI) simulation of warm‐sector rainfall caseThe increased vertical resolutions of lateral boundary conditions (LBCs) can provide more moisture for the CI and upscale convective growth process through marine boundary layer jetHigher temporal frequency LBCs is help to alleviate the western position bias of rain belt by reducing the temporal interpolation error [ABSTRACT FROM AUTHOR]

1.Embryonic stages before birth are crucial for poultry muscle development, as this determines muscle mass in adulthood. This study characterised the distinction in embryonic pectoral muscle development between Wuzong (WZE, small) and Shitou (STE, large) geese (two indigenous goose breeds in Guangdong Province, China) at embryonic days 15 (E15), 23 (E23) and the day of hatching (P1) to gain insights into the regulatory mechanisms of muscle development. 2.The results showed that STE had significantly higher myofibre density during E15-P1 and had significantly larger myofibre diameter at E15 than WZE. By RNA-sequencing analysis, 19 507 genes were detected, and 7121 differentially expressed genes (DEGs) were identified. 3.Gene expression distinctions between breeds began increasing from E23, and WZE had different gene expression profiles compared to STE. A GO analysis of DEGs indicated that myo-genes involved at E15 may influence distinct pectoral muscle development characteristics between WZE and STE. The RT-qPCR results were consistent with the RNA-sequencing analysis. Four muscle structure protein coding genes (MYL2, MYL3, TNNI2 and TNNC2 and three other functional genes (CAV3, CACNA1S and NOS1) were identified in a predicted interaction network. These functional genes may interact with muscle structural protein coding genes to regulate embryonic pectoral muscle development in WZE and STE geese. 4.The study revealed that STE and WZE had divergent embryonic pectoral muscle development patterns and these differences may begin before E15. [ABSTRACT FROM AUTHOR]

The article discusses a study that analyzed baseline concentrations and spatial distribution of trace metals in surface soils of Guangdong Province, China. It is hoped that the information obtained in this study will help identify the potential hotspots of heavy metal contamination and establish proper soil cleanup standards for toxic trace metals in the region. Results showed that the concentrations of most trace metals except for lead (Pb) and mercury (Hg) were lower than those in Chinese soils and worldwide soils. Spatial variability of trace metal concentrations revealed that spatial distributions of trace metal concentrations are correlated to the regional geological characters with high concentrations of trace metals.

Application of superphosphate at establishment as basal fertilizer increased tree growth and survival of Eucalyptus urophylla in a 4.5-year-old trial near Gaoyao, Guangdong, China. It also increased P and N concentrations in young fully expanded leaves at one year and biomass in all tree components. The addition of 20, 50 and 200 kg P ha-1 increased stand volume by five to seven times of the mean annual increment of trees without P. The more P applied, the higher the percentage of stem-wood and the lower the relative allocation of biomass belowground. The low P concentrations in leaves and roots at 20 kg P ha-1 at year 4.5 suggested the withdrawal of P from the biomass, through internal cycling. The addition of P increased N, P, K, Ca and Mg uptake. The 200 kg P ha-1 treatment was optimal both for wood chip production and economic return. [ABSTRACT FROM AUTHOR]