Detecting Long-Term Dry Matter Yield Trend of Sorghum-Sudangrass Hybrid and Climatic Factors Using Time Series Analysis in the Republic of Korea

Abstract

Despite the gradual increase in livestock feed demands, the supply faces enormous challenges due to extreme climatic conditions. As the presence of these climatic condition has the potential to affect the yield of sorghum-sudangrass hybrid (SSH), understanding the yield variation in relation to the climatic conditions provides the ability to come up with proper mitigation strategies. This study was designed to detect the effect of climatic factors on the long-term dry matter yield (DMY) trend of SSH using time series analysis in the Republic of Korea. The collected data consisted of DMY, seeding-harvesting dates, the location where the cultivation took place, cultivars, and climatic factors related to cultivation of SSH. Based on the assumption of normality, the final data set (n = 420) was generated after outliers had been removed using Box-plot analysis. To evaluate the seasonality of DMY, an augmented Dickey Fuller (ADF) test and a correlogram of Autocorrelation Function (ACF) were used. Prior to detecting the effect of climatic factors on the DMY trend, the Autoregressive Integrated Moving Average (ARIMA) model was fitted to non-seasonal DMY series, and ARIMA (2, 1, 1) was found to be the optimal model to describe the long-term DMY trend of SSH. ARIMA with climatic factors (ARIMAX) detected significance (p < 0.05) of Seeding-Harvesting Precipitation Amount (SHPA) and Seeding-Harvesting Accumulated Temperature (SHAMT) on DMY trend. This does not mean that the average temperature and duration of exposure to sunshine do not affect the growth and development of SSH. The result underlines the impact of the precipitation model as a major factor for the seasonality of long-term DMY of SSH in the Republic of Korea.

Impact of abnormal climate events on the production of Italian ryegrass as a season in Korea

“…identify the trends in yields and climatic factors as a form of climate change research in the Republic of Korea [21][22][23]. The drawback of performing this study using historical climate information was that it could not reflect abnormal climate conditions because only normal climates conditions because only normal climate conditions were taken into account.…”

“…As part of a complex natural eco-system, the information on climate and soil factors was used to generate the structure of causality contains their direct and/or indirect pathways for forage crops, such as IRG [ 17 , 18 ], forage barley [ 19 ] and forage rye [ 20 ]. Climate data were also used to identify the trends in yields and climatic factors as a form of climate change research in Korea [ 21 – 23 ]. The drawback of performing this study using historical climate information was that it could not reflect abnormal climate conditions because only normal climates conditions because only normal climate conditions were taken into account.…”

Assessment of weather events impacts on forage production trend of sorghum-sudangrass hybrid

“…Thus, it was recommended to seed and harvest within 5 days to secure a stable yield. Long-term sorghum-sudangrass hybrid yield trends affected by temperature, precipitation, and sunshine duration, the relationship was not clearly evaluated [ 25 ]. Hence, research is necessary to understand in the significant weather event impact on forage crop production during summer growing season.…”

“…Dixon et al [ 26 ], the mean temperature, accumulated solar radiation, mean soil moisture and accumulated precipitation were considered to predict corn yield. Furthermore, growing degree days (GDD), accumulated rainfall and irradiation were considered for modeling yield trend of summer forage crops [ 25 , 27 ]. Therefore, the prediction of future sorghum-sudangrass production was developed based on climate related sorghum-sudangrass production data appearing in the previous trials.…”

Effect of Heavy Rainfall Events on the Dry Matter Yield Trend of Whole Crop Maize (Zea mays L.)

“…The effect of summer depression on the yield of a pasture-based forage production system has also been the area of focus in relation to trends [9]. Chemere et al [10,11] detected the effect of climatic factors on the DMY trend of WCM and a sorghum-sudangrass hybrid using time-series analysis. Despite several climate-based models having been generated to estimate the yield of forage crops, the effect of weather events on yield trend and the extent of fluctuation in the yield of forage crops have often been overlooked.…”