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The vegetation net primary productivity (NPP) is a key indicator for evaluating vegetation carbon sequestration. Exploring its spatiotemporal changes and impact factors is essential for coal mining and ecological restoration in open‐pit mining areas. This study utilized the Carnegie‐Ames‐Stanford‐Approach (CASA) model to calculate monthly vegetation NPP in the Xiwan mine area, a typical open‐pit mine in northwestern China. The trend, stability, and persistence analysis were conducted, along with the development of a grading method to examine the vegetation NPP spatiotemporal variation across different land cover types. Statistical grading and correlation analysis were used to explore the relationships between the topographical factors, meteorological factors, human activities, and vegetation NPP. The following results were obtained: (1) The vegetation NPP in the study area exhibited a high stability and anti‐persistent decrease in trend. NPP reached a peak of 143.49 g C/(m2 year) in 2017, but declined to a low of 118.38 g C/(m2 year) in 2021. (2) The vegetation NPP decreases with increasing elevation and slope, and a relatively strong correlation with temperature and precipitation was also observed. (3) The impact intensity of human activities on vegetation NPP exhibited a rising and fluctuating volatile trend. In 2021, the inhibition of vegetation NPP by human activities reached its peak at 166.42 g C/(m2 year), with an impact effect share of 36.9%. This research provides a comprehensive framework for vegetation NPP analysis in open‐pit mining, offering valuable insights for ecological conservation in mining ecosystems. [ABSTRACT FROM AUTHOR]

The white back planthopper (WBPH), Sogatella furcifera (Horváth) (Hemiptera: Delphacidae), is an important destructive rice pest in Asia that has caused serious economic losses in the main rice‐producing areas of China. To effectively manage this rice pest, it is necessary to investigate its genetic variation and genetic structure and speculate the migration route in China. In this study, we used 12 nuclear microsatellite loci to analyse the genetic variation, gene flow and genetic structure of WBPH in 25 geographic populations in China. Overall, high levels of genetic diversity and genetic differentiation among most populations were detected. Neighbour‐joining dendrograms, STRUCTURE and principal coordinate analysis (PCoA) revealed three genetically distinct groups and exhibited an admixed phylogeographic structure. There was a significant low positive correlation between genetic and geographic distances (r2 = 0.105, p = 0.001), which indicated the role of geographic isolation in the genetic structure of WBPH. Migrant routes detection indicated frequent gene flow exchange between North China and Central China, and low bidirectional gene flows between Northeast China and other regions were detected. Accordingly, this study provides useful data for resolving the genetic relationships and large‐scale migration route of the WBPH and thus contributes to developing more effective management strategies for controlling this pest. [ABSTRACT FROM AUTHOR]

Tropical and subtropical acidic soils have been well documented as hotspots of global soil nitrogen (N) oxide (i.e., nitrous oxide (N2O) and nitric oxide (NO) emissions). While the effectiveness of possible mitigation options has been extensively examined in croplands, little is known about their effectiveness in reducing N‐oxide emissions from acidic soils of rapidly expanding tea plantations in China. Here, we conducted a 2‐year field experiment to investigate how organic substitution for synthetic fertilizer and biochar amendment affect soil N‐oxide emissions from a subtropical tea plantation. Across the 2‐year measurement period, full organic substitution for synthetic fertilizer significantly increased N2O emissions by an average of 17% while had a lower NO emission compared to synthetic fertilizer alone. Our global meta‐analysis further revealed that full or partial organic fertilizer substitution resulted in a 29% (95% confidence interval: 5%–60%) increase of N2O emissions from acidic soils. In contrast, irrespective of fertilizer type, biochar amendment significantly reduced N2O emissions by 14% in the first but not second experimental year, suggesting a transient effect. The trade‐off effect of full organic substitution on N2O and NO emissions may be attributed to the favorable conditions for N2O production due to the stimulated activity of nitrifiers and denitrifiers. The suppression of N2O emission following biochar amendment was probably due to promoted further reduction of N2O to dinitrogen. The fertilizer‐induced emission factor (EF) of N2O (2.1%) in the tea plantation was greater than the current IPCC default value, but the EF of NO (0.8%) was comparable to the global estimate. Taken together, while biochar amendment could have mitigation potential, cautions are needed when applying organic substitution for synthetic fertilizer as mitigation options for acidic soils as hotspots of N‐oxide emissions. [ABSTRACT FROM AUTHOR]

Atmospheric deposition is a global and increasing threat to ecosystem function. Here, we analyzed bulk and wet deposition of inorganic N, total phosphorus (TP) and δ15N of NH4-N and NO3-N at three sites in Nanjing from March 2010 to February 2012. Results showed that bulk deposition fluxes of inorganic N and TP averaged 54.82 kg N ha-1 year-1 and 1.82 kg P ha-1 year-1, respectively. The N/P bulk deposition ratio reached 30/1, leading ecosystems toward P-limitation. Wet deposition fluxes of inorganic N and TP were 25.65 kg N ha-1 year-1 and 1.29 kg P ha-1 year-1, respectively, suggesting the potential contribution of inorganic N from dry deposition. Based on the δ15N values of NH4-N and NO3-N and model results, we found that chemical fertilizers and animal manures contributed to the reduced N deposition and fossil fuel and soil emissions contributed to the oxidized N deposition, depending upon the time and site. Agriculture sector contributed almost twice as industry while animal manures contributed significantly within agriculture. [ABSTRACT FROM AUTHOR]

Three rice planthopper species, Nilaparvata lugens, Sogatella furcifera and Laodelphax striatellus, are destructive rice pests that cause serious economic losses in major rice‐producing regions of China. Understanding their dispersal patterns and potential distribution areas is crucial for effective management and control. Based on historical climate data and simulated future climate data combined with species occurrence data, the dispersal patterns of three planthopper species were analysed and their potential distributions were predicted. The results showed that from 1993 to 2022, the suitable areas for the three rice planthoppers gradually expanded. By 2022, the total suitable area for S. furcifera reached 478.35 × 104 km2, followed by 376.02 × 104 km2 for L. striatellus and 264.97 × 104 km2 for N. lugens. The optimum area for S. furcifera exhibited the most significant increase, expanding by 136.07 × 104 km2. The species has extended its range from southern China to the northeastern and northwestern regions within the past three decades. The suitable areas for L. striatellus and N. lugens did not show a significant spread trend. In addition, compared to that in 2022, the total suitable area for the three rice planthopper species increased slightly from 2041 to 2060. The study revealed that the wettest monthly rainfall and the lowest temperature were the most influential factors affecting the distributions of these planthopper species. This study provides valuable insights into the dispersal patterns and potential distribution of rice planthoppers in China and provides a theoretical basis for effective prevention and control strategies for destructive rice pests. [ABSTRACT FROM AUTHOR]