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With the increasingly acute contradictions between shortage of bonanza phosphorus resources and phosphate fertilizer demands, to develop an efficient use technology for low-grade phosphate rocks (LGPR) was an inevitable choice. In this study, the physicochemical pro-release phosphate rock (PCPR) was prepared by adding modified lignin during the process of ultra-fine grinding LGPR. The relationship between phosphorus chemical composition of PCPR, molecular structure and fertilizer efficiency was explored by chemical analysis, spectral analysis and pot experiment. The results showed that after pro-release treatment of phosphate rock (PR), available phosphorus, reactive phosphorus and soluble phosphorus levels were significantly increased compared with PR. The available phosphorus content increased by 40%, the reactive phosphorus content increased more than 3.5 times, and 6 consecutive extraction soluble phosphorus accumulation increased by 24 times. The structure of the PR showed the pro-release processing would significantly increase particle fineness and specific surface area of PR , strengthen the characteristic absorption peak intensity of PO 4 3-, HPO 4 2-, replace the Cl -, F -, Fe 2+ in the apatite and change the phase composition of PR. Pot experiment results showed corn biomass and phosphorus utilization processed by the PCPR were much higher than superphosphate (SP), diammonium phosphate(DAP), and significantly improve soil phosphorus content. The high soluble phosphorus and active phosphorus in PCPR providing the moderate continuous phosphorus supply intensity was the main reason for its high bioavailability. The combination of a static extraction and continuous extraction of reactive phosphorus and soluble phosphorus was an appropriate evaluation of physicochemical pro-release effect.

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Phosphorus is a nonrenewable and irreplaceable limited resource, and over 90% of phosphorus in influenttransfers into sludge in wastewater treatment plants. In this study, thermally activated peroxydisulfate (TAP) treatment was combined with struvite precipitation to enhance waste activated sludge (WAS) dewaterability and phosphorus recovery. TAP simultaneously enhanced dewaterability and solubilization of WAS. The optimal conditions of TAP treatment were PDS dosage 2.0 mmol/g TSS, 80 °C, pH 4.0~7.0 and 40 min, which enhanced dewaterability (capillary suction time (CST) from 94.2 s to 28.5 s) and solubilization (PO43−-P 177.71 mg/L, NH4+-N 287.22 mg/L and SCOD 10754 mg/L). Radical oxidation disintegrated tightly bound extracellular polymeric substances (TB-EPS) and further released bound water. The acidification effect neutralized the negative surface charge of colloid particles. Compared with thermal hydrolysis, TAP effectively promoted the release of PO43−, NH4+ and SCOD. Cation exchange removed most Ca and Al of the TAP treated supernatant. The optimal conditions of struvite precipitation were Mg/P 1.4 and pH 10.0, which achieved phosphorus recovery of 95.06% and struvite purity of 94.94%. The income obtained by struvite adequately covers the cost of struvite precipitation and the cost of WAS treatment is acceptable.

Evapotranspiration (ET) is a critical process that regulates the transfer of heat and water between land and the atmosphere. While satellite‐based ET algorithms can provide area‐wide daily ET estimates, few are independent of local meteorological measurements. The Variant of the Moderate Resolution Imaging Spectroradiometer Standard Evapotranspiration Algorithm (VISEA) can potentially run without ground‐based observations. However, the surface energy budgets used in VISEA generally overpredict daily net radiation and related ET. To improve the accuracy of net radiation and ET, we incorporated Brutsaert's atmosphere emissivity model and corrected the routine to calculate the downward long‐wave radiation on cloudy days (which we called VISEA2023 model). The VISEA2023 model predicted net radiation and ET that agreed well with measurements at seven ChinaFlux sites, with an R2 of 0.8 and an Root Mean Square Error (RMSE) of 30 W m−2 for net radiation, and an R2 of 0.6 and an RMSE of 1 mm day−1 for ET, respectively. Additionally, the VISEA2023 model is more robust in comparison to the Variable Infiltration Capacity hydrologic model output in 10 major river basins and 80 sub‐river basins, with an R2 of 0.91 (0.78) and an RMSE of 85 (127.4) mm year−1, than MOD16, which has an R2 of 0.81 (0.82) and an RMSE of 134.8 (157.7) mm year−1, and Advanced Very High Resolution Radiometer ET, which has an R2 of 0.92 (0.62) and an RMSE of 90.1 (136.1) mm year−1. The improved VISEA2023 model can offer near‐real‐time ET on a larger scale, improving our understanding of water cycles and their relation to climate change.