Sensitivity analysis of WOFOST model crop parameters in different grassland types

doi:10.11686/cyxb2021391

Abstract

Abstract:

World Food Studies （WOFOST） is a simulation model for the quantitative analysis of the growth and production of crops. It is based on the physiological and ecological processes of crops， and can be used to predict the effects of CO₂， soil， climate， and other factors on yield. The aim of this study was to conduct a parameter sensitivity analysis for different types of grasslands （i.e.， those under different management measures and climatic conditions）. Four sites were selected in different grassland zones in Tianzhu Zangzu Autonomous County. The extended Fourier amplitude sensitivity test （EFAST） method was used to analyze the sensitivity of different parameters of grasslands in the WOFOST model under potentially productive and water-restricted conditions based on meteorological data， field sampling data， and soil data. The accuracy of the WOFOST simulations for grasslands with different degrees of coverage were evaluated by comparisons with measured data. The sensitive parameters for estimating grassland above-ground biomass （AGB） under potentially productive conditions were specific leaf area （SLATB）， light-use efficiency of a single leaf （EFFTB）， maximum leaf CO₂ assimilation rate at daily temperatures of 0 and 40 ℃ （AMAXTB）， relative maintenance respiration rate of roots （RMR）， and fraction of root and leaf system out of total dry matter （FRTB and FLTB）； and the sensitive parameters under restricted water conditions were SLATB， AMAXTB， RMR， and FLTB. The sensitive parameters for estimating leaf area index （LAI） were the same under both production levels. From emergence to 60 d after emergence， the LAI was mainly affected by SLATB， FLTB， and FRTB. From 60 to 200 d after emergence， the sensitive parameters were FLTB， FRTB， SLATB， and extinction coefficient for diffuse visible light （KDIFTB）. After the LAI began to decline， it was enhanced by KDIFTB. Compared with measured values， the simulated values of AGB were most accurate for slope meadow （R²=0.94， RMSE=11.71 g·m^-2） and least accurate for alpine meadow （R²=0.83， RMSE=32.68 g·m^-2）； and the simulated values of LAI were most accurate for temperate desert steppe （R²=0.96， RMSE=0.02） and least accurate for warm steppe （R²=0.66， RMSE=0.38）. Thus， the application of the sensitivity analysis method in the WOFOST model reduces the influence of human subjectivity and greatly shortens the parameter adjustment time.

Key words: WOFOST model, EFAST, global sensitivity analysis, grassland, Tianzhu Zangzu Autonomous County

Ge-xia QIN, Jing WU, Chun-bin LI, Shuai-jie SHEN, Huai-hai LI, Dao-han YANG, Mei-rong JIAO, Qi QI. Sensitivity analysis of WOFOST model crop parameters in different grassland types[J]. Acta Prataculturae Sinica, 2022, 31(5): 13-25.

Figures/Tables 7

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参数Parameter	参数范围 Range of parameter in WOFOST
作物初始的干物质重量Initial total crop dry weight （TDWI）	87~161
出苗时叶面积指数Leaf area index at emergence （LAIEM）	0.10185~0.14650
叶面积指数最大相对增长速率Maximum relative increase in LAI （RGRLAI）	0.007151~0.008326
比叶面积Specific leaf area ［SLATB₀ （DVS=0）］	0.001008~0.002532
比叶面积Specific leaf area ［SLATB_0.5（DVS=0.5）］	0.001008~0.002532
比叶面积Specific leaf area ［SLATB₂（DVS=2.0）］	0.001008~0.002532
叶片在35 ℃时的生命周期Life span of leaves growing at 35 ℃ （SPAN）	25.17~30.43
叶龄下限温度Lower threshold temperature for aging of leaves （TBASE）	-3~3
漫射可见光的消光系数Extinction coefficient for diffuse visible light ［KDIFTB₀（DVS=0）］	0.45~0.56
漫射可见光的消光系数Extinction coefficient for diffuse visible light ［KDIFTB₂（DVS=2.0）］	0.45~0.56
单叶片光能利用率Light-use efficiency of single leaf ［EFFTB₀ （T=0 ℃）］	0.405~0.455
单叶片光能利用率Light-use efficiency of single leaf ［EFFTB₄₀ （T=40 ℃）］	0.405 ~ 0.455
最大二氧化碳同化速率Maximum leaf CO₂ assimilation rate ［AMAXTB₀ （DVS=0.0）］	18.247~40.413
最大二氧化碳同化速率Maximum leaf CO₂ assimilation rate ［AMAXTB₁ （DVS=1.0）］	18.247~40.413
最大二氧化碳同化速率Maximum leaf CO₂ assimilation rate ［AMAXTB_1.3 （DVS=1.3）］	18.247~40.413
最大二氧化碳同化速率Maximum leaf CO₂ assimilation rate ［AMAXTB₂ （DVS=2.0）］	4.032~4.928
最大二氧化碳同化速率衰减因子Reduction factor of AMAX ［TMPFTB₀ （T=0 ℃）］	0.009~0.011
最大二氧化碳同化速率衰减因子Reduction factor of AMAX ［TMPFTB₁₀ （T=10 ℃）］	0.44~0.56
叶片同化物转化效率Efficiency of conversion into leaves （CVL）	0.6165~0.7535
贮藏器官同化物转化效率Efficiency of conversion into storage organ （CVO）	0.6381~0.7799
根同化物转化效率Efficiency of conversion into roots （CVR）	0.6246~0.7634
茎同化物转化效率Efficiency of conversion into stems （CVS）	0.5958~0.7282
温度每升高10 °C，呼吸速率相对增加Relative increase in respiration rate per 10 °C temperature increase （Q₁₀）	1.8~2.2
叶片相对维持呼吸速率Relative maintenance respiration rate of leaves （RML）	0.027~0.033
贮藏器官相对维持呼吸速率Relative maintenance respiration rate of storage organ （RMO）	0.009~0.011
根相对维持呼吸速率Relative maintenance respiration rate of roots （RMR）	0.0135~0.0165
总干物质占根系的比例Fraction of total dry matter to roots ［FRTB₀（DVS=0）］	0.45~0.55
总干物质占根系的比例Fraction of total dry matter to roots ［FRTB_0.4 （DVS=0.4）］	0.153~0.187
总干物质占根系的比例Fraction of total dry matter to roots ［FRTB_0.7 （DVS=0.7）］	0.063~0.077
总干物质占根系的比例Fraction of total dry matter to roots ［FRTB_0.9 （DVS=0.9）］	0.027~0.033
地上干物质到叶片的比例Fraction of aboveground dry matter to leaves ［FLTB₀ （DVS=0）］	0.62~0.78
地上干物质到叶片的比例Fraction of aboveground dry matter to leaves ［FLTB_0.25 （DVS=0.25）］	0.53~0.75
地上干物质到叶片的比例Fraction of aboveground dry matter to leaves ［FLTB_0.5 （DVS=0.5）］	0.45~0.55
地上干物质到叶片的比例Fraction of aboveground dry matter to leaves ［FLTB_0.646 （DVS=0.646）］	0.27~0.33
水分胁迫对叶片的最大相对死亡率Maximum relative death rate of leaves due to water stress （PERDL）	0.27~0.33
根的相对死亡率Relative death rate of roots ［RDRRTB_1.5（DVS=1.5）］	0.018~0.022
根的相对死亡率Relative death rate of roots ［RDRRTB_2.0（DVS=2.0）］	0.018~0.022
茎的相对死亡率Relative death rate of stems ［RDRSTB_1.5 （DVS=1.5）］	0.018~0.022
茎的相对死亡率Relative death rate of stems ［RDRSTB_2.0 （DVS=2.0）］	0.018~0.022
初始根深Initial rooting depth （RDI）	2~10
最大日生根深度增加量Maximum daily increase in rooting depth （RRI）	0~1.12
最大根深Maximum rooting depth （RDMCR）	30.5~107.5

参数Parameter	参数范围 Range of parameter in WOFOST
作物初始的干物质重量Initial total crop dry weight （TDWI）	87~161
出苗时叶面积指数Leaf area index at emergence （LAIEM）	0.10185~0.14650
叶面积指数最大相对增长速率Maximum relative increase in LAI （RGRLAI）	0.007151~0.008326
比叶面积Specific leaf area ［SLATB₀ （DVS=0）］	0.001008~0.002532
比叶面积Specific leaf area ［SLATB_0.5（DVS=0.5）］	0.001008~0.002532
比叶面积Specific leaf area ［SLATB₂（DVS=2.0）］	0.001008~0.002532
叶片在35 ℃时的生命周期Life span of leaves growing at 35 ℃ （SPAN）	25.17~30.43
叶龄下限温度Lower threshold temperature for aging of leaves （TBASE）	-3~3
漫射可见光的消光系数Extinction coefficient for diffuse visible light ［KDIFTB₀（DVS=0）］	0.45~0.56
漫射可见光的消光系数Extinction coefficient for diffuse visible light ［KDIFTB₂（DVS=2.0）］	0.45~0.56
单叶片光能利用率Light-use efficiency of single leaf ［EFFTB₀ （T=0 ℃）］	0.405~0.455
单叶片光能利用率Light-use efficiency of single leaf ［EFFTB₄₀ （T=40 ℃）］	0.405 ~ 0.455
最大二氧化碳同化速率Maximum leaf CO₂ assimilation rate ［AMAXTB₀ （DVS=0.0）］	18.247~40.413
最大二氧化碳同化速率Maximum leaf CO₂ assimilation rate ［AMAXTB₁ （DVS=1.0）］	18.247~40.413
最大二氧化碳同化速率Maximum leaf CO₂ assimilation rate ［AMAXTB_1.3 （DVS=1.3）］	18.247~40.413
最大二氧化碳同化速率Maximum leaf CO₂ assimilation rate ［AMAXTB₂ （DVS=2.0）］	4.032~4.928
最大二氧化碳同化速率衰减因子Reduction factor of AMAX ［TMPFTB₀ （T=0 ℃）］	0.009~0.011
最大二氧化碳同化速率衰减因子Reduction factor of AMAX ［TMPFTB₁₀ （T=10 ℃）］	0.44~0.56
叶片同化物转化效率Efficiency of conversion into leaves （CVL）	0.6165~0.7535
贮藏器官同化物转化效率Efficiency of conversion into storage organ （CVO）	0.6381~0.7799
根同化物转化效率Efficiency of conversion into roots （CVR）	0.6246~0.7634
茎同化物转化效率Efficiency of conversion into stems （CVS）	0.5958~0.7282
温度每升高10 °C，呼吸速率相对增加Relative increase in respiration rate per 10 °C temperature increase （Q₁₀）	1.8~2.2
叶片相对维持呼吸速率Relative maintenance respiration rate of leaves （RML）	0.027~0.033
贮藏器官相对维持呼吸速率Relative maintenance respiration rate of storage organ （RMO）	0.009~0.011
根相对维持呼吸速率Relative maintenance respiration rate of roots （RMR）	0.0135~0.0165
总干物质占根系的比例Fraction of total dry matter to roots ［FRTB₀（DVS=0）］	0.45~0.55
总干物质占根系的比例Fraction of total dry matter to roots ［FRTB_0.4 （DVS=0.4）］	0.153~0.187
总干物质占根系的比例Fraction of total dry matter to roots ［FRTB_0.7 （DVS=0.7）］	0.063~0.077
总干物质占根系的比例Fraction of total dry matter to roots ［FRTB_0.9 （DVS=0.9）］	0.027~0.033
地上干物质到叶片的比例Fraction of aboveground dry matter to leaves ［FLTB₀ （DVS=0）］	0.62~0.78
地上干物质到叶片的比例Fraction of aboveground dry matter to leaves ［FLTB_0.25 （DVS=0.25）］	0.53~0.75
地上干物质到叶片的比例Fraction of aboveground dry matter to leaves ［FLTB_0.5 （DVS=0.5）］	0.45~0.55
地上干物质到叶片的比例Fraction of aboveground dry matter to leaves ［FLTB_0.646 （DVS=0.646）］	0.27~0.33
水分胁迫对叶片的最大相对死亡率Maximum relative death rate of leaves due to water stress （PERDL）	0.27~0.33
根的相对死亡率Relative death rate of roots ［RDRRTB_1.5（DVS=1.5）］	0.018~0.022
根的相对死亡率Relative death rate of roots ［RDRRTB_2.0（DVS=2.0）］	0.018~0.022
茎的相对死亡率Relative death rate of stems ［RDRSTB_1.5 （DVS=1.5）］	0.018~0.022
茎的相对死亡率Relative death rate of stems ［RDRSTB_2.0 （DVS=2.0）］	0.018~0.022
初始根深Initial rooting depth （RDI）	2~10
最大日生根深度增加量Maximum daily increase in rooting depth （RRI）	0~1.12
最大根深Maximum rooting depth （RDMCR）	30.5~107.5

[1]	Ge-xia QIN, Jing WU, Chun-bin LI, Zhen-xia JI, Zheng-chao QIU, Ying LI. Inversion of grassland aboveground biomass in Tianzhu Zangzu Autonomous County based on a machine learning algorithm [J]. Acta Prataculturae Sinica, 2022, 31(4): 177-188.
[2]	Cai-he ZHANG, Chun-bin LI, Jing WU. Definition of Comprehensive Sequential Classification System subclasses in Chinese montane grassland [J]. Acta Prataculturae Sinica, 2022, 31(3): 16-25.
[3]	Lei ZHOU, Xue WEI, Chang-ting WANG, Peng-fei WU. Differences in soil microarthropod community structure in alpine grasslands with differing degrees of degradation [J]. Acta Prataculturae Sinica, 2022, 31(3): 34-46.
[4]	Ya-hui WANG, Wen-jia TANG, Sen LI, Hong-yan ZHAO, Jia-li XIE, Chao MA, Chang-zhen YAN. Change in grassland productivity in Qinghai Province and its driving factors [J]. Acta Prataculturae Sinica, 2022, 31(2): 1-13.
[5]	Ren-ping ZHANG, Jing GUO, Xiao-fang MA, Wei-yong GUO. Grassland phenology extraction for Xinjiang Province and trend analysis using MODIS data [J]. Acta Prataculturae Sinica, 2022, 31(1): 1-12.
[6]	Xiao-yu HAN, Ning GUO, Dong-dong LI, Ming-yang XIE, Feng JIAO. Effects of nitrogen addition on soil carbon and nitrogen and biomass change in different grassland types in Inner Mongolia [J]. Acta Prataculturae Sinica, 2022, 31(1): 13-25.
[7]	Wen-ming MA, Chao-wen LIU, Qing-ping ZHOU, Zhuo-ma DENGzeng, Si-hong TANG, Diliyaer·mohetaer, Chen HOU. Effects of shrub encroachment on soil aggregate ecological stoichiometry and enzyme activity in alpine grassland [J]. Acta Prataculturae Sinica, 2022, 31(1): 57-68.
[8]	Jing-hai WANG, Guang LI, Min-hua YIN, Guang-ping QI, Yan-xia KANG, Yan-lin MA. Effects of regulated deficit irrigation on the soil environment and forage growth of mixed-species forage plantings in China’s high-cold desert area [J]. Acta Prataculturae Sinica, 2022, 31(1): 95-106.
[9]	Ting-mei WU, Hui-long LIN, Di FAN, Chang-ting JI, Yu-ting ZHAO, Jing-qiong WEI. Factors influencing the scale of herdsmen’s livestock farming in tundra alpine grassland-A case study from Qinghai Province [J]. Acta Prataculturae Sinica, 2021, 30(9): 117-126.
[10]	Jia-li LIU, Jian-rong FAN, Xi-yu ZHANG, Chao YANG, Fu-bao XU, Xiao-xue ZHANG, Bo LIANG. Remote sensing estimation of vegetation cover in alpine grassland in the growing and non-growing seasons [J]. Acta Prataculturae Sinica, 2021, 30(9): 15-26.
[11]	Mei-ling SONG, Yu-qin WANG, Hong-sheng WANG, Gen-sheng Bao. Effect of Epichloë endophyte on the litter decomposition of Stipa purpurea in alpine grassland [J]. Acta Prataculturae Sinica, 2021, 30(9): 150-158.
[12]	Qing ZHANG, Lu-yao LIU, Xue XU, Peng HAN, Yan-yun ZHAO, Jian-ming NIU, Yong DING. Sustainable development of family ranches in the Inner Mongolian grassland [J]. Acta Prataculturae Sinica, 2021, 30(9): 168-181.
[13]	Gang FU, Jun-hao WANG, Shao-wei LI, Ping HE. Responses of forage nutrient quality to grazing in the alpine grassland of Northern Tibet [J]. Acta Prataculturae Sinica, 2021, 30(9): 38-50.
[14]	Jing-dong ZHAO, Wuyunna, Yan-tao SONG. Effect of short-term fencing on the forage quality of plant communities in degraded grassland in Northwestern Liaoning [J]. Acta Prataculturae Sinica, 2021, 30(9): 51-61.
[15]	Hui-long LIN, Yan-fei PU, Dan-ni WANG, Hai-li MA. Index insurances for grasslands： A review and the Chinese scheme design [J]. Acta Prataculturae Sinica, 2021, 30(8): 171-185.