Graphical approach to assess the soil fertility evaluation model validity for rice (case study: southern area of Merapi Mountain, Indonesia)

International Conference on Climate Change: Challenges and Opportunity on Environment Degradation Researches

地球科学;生态环境科学

Julianto, E.A.^1,2 ; Suntoro, W.A.^3 ; Dewi, W.S.^3 ; Partoyo^2

Doctoral Program of Agricultural Science, Graduate School, Sebelas Maret University, Surakarta Jl. Ir. Sutami No. 36A, Surakarta, Indonesia^1

Dept. of Agrotechnology, Universitas Pembangunan Nasional Veteran Yogyakarta, Jl. SWK 104, Lingkar Utara Condong Catur Yogyakarta, Indonesia^2

Dept. of Soil Science, Fac. of Agriculture, Sebelas Maret University, Jl. Ir. Sutami No. 36A, Surakarta, Indonesia^3

关键词: Evaluation modeling;    Evaluation models;    Goodness of fit;    Graphical approach;    Regression coefficient;    Residual curves;    Rice production;    Soil fertility;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/129/1/012012/pdf
DOI  :  10.1088/1755-1315/129/1/012012

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

Climate change has been reported to exacerbate land resources degradation including soil fertility decline. The appropriate validity use on soil fertility evaluation could reduce the risk of climate change effect on plant cultivation. This study aims to assess the validity of a Soil Fertility Evaluation Model using a graphical approach. The models evaluated were the Indonesian Soil Research Center (PPT) version model, the FAO Unesco version model, and the Kyuma version model. Each model was then correlated with rice production (dry grain weight/GKP). The goodness of fit of each model can be tested to evaluate the quality and validity of a model, as well as the regression coefficient (R2). This research used the Eviews 9 programme by a graphical approach. The results obtained three curves, namely actual, fitted, and residual curves. If the actual and fitted curves are widely apart or irregular, this means that the quality of the model is not good, or there are many other factors that are still not included in the model (large residual) and conversely. Indeed, if the actual and fitted curves show exactly the same shape, it means that all factors have already been included in the model. Modification of the standard soil fertility evaluation models can improve the quality and validity of a model.