DOI: 10.5061/dryad.xd2547dsk
title: Data from: Quantifying soil gaseous nitrogen losses from nitrification and denitrification based on nitrogen isotope model

description: Gaseous nitrogen (N) losses from nitrification and denitrification
 (NO+N2O+N2) pathways contribute a significant fraction of the total N
 losses from cropland ecosystems. However, a large uncertainty exists in
 estimating the NO+N2O+N2 losses, hindering effective management of the
 global N budget. Here we proposed a novel isotope model, which considers N
 fertilizer, ammonia (NH3) volatilization and crop harvest after testing
 the steady state assumption of soil δ15N and N pool for croplands, and
 justified if it could be successfully applied to constrain NO+N2O+N2
 losses from cropland ecosystems. We compiled the first bulk-soil δ15N
 dataset of 0-30cm soils (n=738) from croplands and produced a global map
 of cropland soil δ15N, which is crucial input data for N isotope model to
 quantify NO+N2O+N2 losses. The results show that the cropland soil δ15N
 ranges from 3.5 to 9.0‰, with a mean value of 6.6±0.8‰ (mean ± standard
 deviation). The estimated NO+N2O+N2 losses accounted for an average of
 17±9% of N outputs and were 35.86±24.17 kg N ha-1 yr−1 in China’s rice
 paddies, with an increasing trend from Central China to South or North
 China. The estimations were comparable with the results from
 observation-constrained Denitrification-Decomposition modelling (38.9±4.8
 kg N ha−1 yr-1) and in good agreement with experimental observations at
 site scale (R2=0.58). Our results suggest that soil N isotopes, as a
 quantitative tracer, provide a valuable alternative approach to constrain
 the NO+N2O+N2 losses in croplands at large geographic scales.
description: # Data from: Quantifying soil gaseous nitrogen losses from nitrification
 and denitrification based on nitrogen isotope model Authors: Haoming Yu;
 Wenxin Ba; Peter Dorsch; Wulahati Adalibieke; Yunting Fang; Longfei Yu;
 Chao Wang; Yihang Duan; Huayan Zhang; Benjamin Z. Houlton; Yan Bo; Yi Wei
 Jian; Xiao Qing Cui; Edith Bai; Feng Zhou Principal Investigator Contact
 Information Name: Haoming Yu Institution: Institute of Carbon Neutrality,
 Laboratory for Earth Surface Processes, College of Urban and Environmental
 Sciences, Peking University, Beijing, P.R. China Address: No.100
 Zhongguancun North Street, Beijing, 100871, China Email:
 [haoming.yu@pku.edu.cn](mailto:haoming.yu@pku.edu.cn) **Date of data
 collection:** 2023-2024 **Description:** This README file describes the
 data package accompanying the above publication. **Data and File
 overview:** **1. Yu_et_al._2025_Data_for_soil_15N_meta** Dataset of the
 results from filtering cropland soil 15N measured research. The columns
 include: **Sheet1: Data for simulating soil 15N** * Title Title of data
 reference * Publication Year Publication year of data reference * Author
 Author of data reference * Latitude () The latitude of the respective site
 * Longitude () The longitude of the respective site * Country The country
 of study sites for data of this experiment or literature * Sampling depth
 (cm) Soil depth for soil collection * Crop type Crop planting types during
 soil collection * Sampling year Year of soil collection * Observed soilN15
 () Soil 15N measured data * Organic fertilizer type/15N () Organic
 fertilizer type and its relative abundance of 15N * Organic fertilizer (kg
 N ha-1 year-1) The amount of organic fertilizer applied in the sampling
 year * Inorganic fertilizer (kg N ha-1 year-1) The amount of inorganic
 fertilizer applied in the sampling year * Inorganic fertilizer type/15N ()
 Inorganic fertilizer type and its relative abundance of 15N The next six
 columns are Random forest input data: (a) exp((MAT+273.15)/100)
 Exponential transformation ofannual average temperature (C). (b)
 exp(Silt/100) Exponential transformation ofsoil silt content (%). (c)
 ln(BNF) Logarithmic transformation ofbiological nitrogen fixation (kg N
 ha-1 year-1). (d) Fer_15N 15N from all types of fertilization (g N ha-1
 year-1). (e) ln(Irrpre) Logarithmic transformation of irrigation and
 annual precipitation (mm). (f) NOy N deposition in form of NOy (kg N ha-1
 year-1). The null annotation data in this Excel represents data that is
 zero in the literature. **Sheet2: Refs_soil15N** * Reference References
 for Sheet 1 **2. Yu_et_al._2025_Data_for_Model_validation_at_site_scales**
 Dataset of the observed data for testing NO+N2O+N2 N loss and runoff and
 leaching N loss. The columns include: **Sheet1: Observed NO+N2O+N2 N loss
 rate** * Title Title of data reference * Journal Publication Journal of
 data reference * Author Author of data reference * Year Publication year
 of data reference * Method Data measurement methods * Insitu/incubation Is
 the data measured in situ or lab incubation * Sample year Year of soil
 collection * Latitude () The latitude of the respective site * Longitude
 () The longitude of the respective site * Location The study sites for
 data of this experiment or literature * Cropping system Crop planting
 types during soil collection * incubation time (day) Incubation time
 during measurement * Sampling depth (cm) Soil depth for soil collection *
 Annual average temperature (C) Average annual temperature at the sampling
 site * Annual precipitation (mm) Annual precipitation at the sampling site
 * N application rate (kg N ha-1) Nitrogen application at the sampling site
 * Fer_15N 15N from all types of fertilization (g N ha-1 year-1) * Observed
 NO+N2O+N2 N loss rate (kg N ha-1 year-1) NO+N2O+N2 N loss rate measured in
 references * Simulated NO+N2O+N2 N loss rate (kg N ha-1 year-1) NO+N2O+N2
 N loss rate simulated in this study * pH pH of soil samples * Silt (%)
 Silt content of soil samples The null annotation data in Excel represents
 data that is not available in the literature. **Sheet2: Refs_Denit_flux**
 * Reference References for Sheet 1 **Sheet3: Observed runoff and leaching
 N** * Title Title of data reference * Year Publication year of data
 reference * Latitude () The latitude of the respective site * Longitude ()
 The longitude of the respective site * Rotation Crop rotation system for
 study site * Region Study sites * Days of growing season Growth season
 length of study site * Annual precipitation (mm) Annual precipitation at
 the respective site * Annual average temperature (C) Average annual
 temperature at the respective site * Observed runoff and leaching N (kg N
 ha-1) Runoff and leaching N loss rate measured in references * Simulated
 runoff and leaching N (kg N ha-1 year-1) Runoff and leaching N loss rate
 simulated in this study * N losses via leakage (kg N ha-1 year-1) N losses
 via leakage measured in references * N loss via runoff (kg N ha-1) N loss
 via runoff measured in references * Fertilized (kg N ha-1) Nitrogen
 application at the respective site * Replacement ratio of organic
 fertilizer % The proportion of organic fertilizer application to total
 nitrogen application at the respective site * Fertilized N types Type of
 fertilizer at the respective site * Fer_15N 15N from all types of
 fertilization (g N ha-1 year-1) * Irrigation (mm) Irrigation amount at the
 respective site **Sheet4: Refs_runoff and leaching N** * Reference
 References for Sheet 3 **3. Yu_et_al._2025_Data_for_Simulation
 result.zip** f_gas_China.mat: For the period 2000 to 2020, the fractions
 of the NO+N2O+N2 losses to total N output in Chinas rice paddies estimated
 by the nitrogen isotope model. N_gas_China.mat: For the period 2000 to
 2020, the NO+N2O+N2 losses in Chinas rice paddies estimated by the
 nitrogen isotope model. soil_15N_rice_China.mat: soil 15N data in Chinas
 rice paddies estimated by randomForest model. soil_15N_world.mat: soil 15N
 data in global cropland estimated by randomForest model. **4. code.mlx**
 The MATLAB script is the code of the main figures in this study.
 **Funding** This study was supported by the National Natural Science
 Foundation of China (42225102, 42361144876), the National Key Research and
 Development Program of China (2023YFD1500802, 2021YFD700801) and the China
 Postdoctoral Science Foundation (2024M760082). **Version changes** Mar 12,
 2025 In the file Yu_et_al._2025_Data_for_soil_15N_meta.xlsx: * Change the
 name of column O from exp(MAT) to exp((MAT + 273.15)/100). * Change the
 name of column P from exp(Silt) to exp(Silt/100).