|Dataset composition||The dataset consists of the following six tables:|
1. Soil nutrient table
The table recorded the long-term locating and monitoring data of topsoil nutrient in Hailun Station, containing 546 entries, which included year, month, day, plot code, sampling subplot description (microtopography), soil type, parent material, crop, sampling depth (cm), sample code, organic matter (g/kg), total N (g/kg), total P (g/kg), total K (g/kg), available N (mg/kg), available P (mg/kg), available K (mg/kg), slowly available K (mg/kg), pH value, exchangeable Ca (mmol/kg(1/2Ca2+)), exchangeable Mg (mmol/kg(1/2 Mg 2+)), exchangeable K (mmol/kg(K+)), exchangeable Na (mmol/kg(Na +)), cation exchange capacity (mmol/kg(+)) and remarks, with a total of 27 fields.
2. Plot information table
The table recorded the profile of the plots monitored by Hailun Station, containing 3 data entries, which included plot code, plot name, plot type, observation starting year, observation objective, experiment design, crop rotation and system, east longitude (°), north latitude (°), altitude (m), parent material, soil type (as per Genetic Soil Classification of China), soil subtype (as per Chinese Soil Taxonomy), with a total of 13 fields.
3. Plot management table
The table recorded the main field management data from plots of Hailun Station, containing 36 data records, which included year, plot code, crop, species, sowing date (year/month/day), harvesting data (year/month/day), irrigation and drainage, fertilizers (including chemical fertilizer, straw and organic fertilizer), fertilization date and method, application rate (by the weight of fertilizers, including the returned straw, kg/ha), carbon application rate (kg C/ha), nitrogen application rate (kg N/ha), phosphor application rate (kg P2O5/ha), potassium application rate (kg K2O/ha), yield (kg/ha), natural disaster, disease and pest, human disturbance, field manager and remarks, with a total of 20 fields.
4. Soil sampling and preservation table
The table recorded the methods of soil sampling and preservation, containing 117 data entries, which included year, plot code, sampling data and weather condition, sampling method, amount of samples preserved, sample number, sample preparation, sample preservation record and sampling staff, with a total of 9 fields.
5. Analysis method table
The table recorded the laboratory analysis method for the properties of each soil nutrient, containing 117 data entries, which included year, item, analysis method, citation standard and reference, with a total of 5 fields.
6. Reference determination table
The table recorded the quality control data by means of reference determination, containing 89 data entries, which included year, reference, analysis item, unit, standard value, uncertainty, analysis method for standard value, means of reference determination, standard deviation of reference determination, repeating times of reference determination, analysis method of reference determination, instrument, analyzer, and auditor, with a total of 14 fields.