模式化氣象變因對尼羅草牧草產量影響

Modeling Climatic Effects on Forage Production of Acroceras macrum

李裕娟(Yuh-Jyuan Lee) ； 楊純明(Chwen-Ming Yang) ； 洪國源(Kuo-Yuan Hong) ； 許福星(Fu-Hsing Hsu)

《作物、環境與生物資訊》 1卷1期 (2004/03) Pp. 39-46

https://doi.org/10.30061/CEB.200403.0006

摘要

本研究於2002年6月至2003年10月共六個作季之試驗期間，分別調查尼羅草(Acroceras macrum Stapf)收割時之植株高度及小區鮮草與乾草產量，並收集試區（臺南縣新化鎮行政院農業委員會畜產試驗所農場）一級農業氣象測站之測值。根據試驗資料分析結果，除了累積日照時數(DSH)之外，六個作季的植株高度及產量和個別氣象變因之間，包括各栽植作季之累積日均溫(DMAT)、累積日降水量(DP)、累積日蒸發量(DE)及累積日射量(IR)，皆未達顯著相關。經將植株高度及產量與此五個氣象變因進行多元線性複迴歸分析，發現鮮草產量與DSH、IR、DE及DMAT等四氣象變因可構成最佳四元直線複迴歸模式，而乾草產量則可與DMAT及DP等二氣象變因構成最佳二元直線複迴歸模式。這些多元直線複迴歸模式之估測值與實測值呈現近似於1:1的比較結果，斜率分別達0.9999及0.9961。另割刈時之尼羅草植株高度與鮮草產量之間亦呈現顯著正相關，顯示生育良好具有較高株高之尼羅草牧草地，可能獲得較多鮮草產量。

關鍵字

尼羅草 ； 氣象變因 ； 牧草產量 ； 植株高度 ； 多元線性複迴歸分析

並列摘要

Field experiments were conducted at the research farm of Taiwan Livestock Research Institute (Hsinhua, Taiwan) to measure plant height and forage yield (fresh weight-based and dry weight-based) of Acroceras macrum Stapf and to collect meteorological data so as to investigate effects of climatic variables on forage production. The daily mean air temperature (DMAT), daily precipitation (DP), daily evaporation (DE), daily irradiance (IR), and daily sunshine hour (DSH) during the six growing seasons, from June 2002 to October 2003, were accumulated to correlate with plant height and forage yield. Results showed that, except the accumulated DSH, no significant difference was found in relations of plant height and forage yield to other climatic variables. By the multiple linear regression analysis, it indicated that fresh weight-based forage yield was best-fitted to a four-variable linear regression model made from the seasonal accumulated values of DMAT, DE, IR and DSH, while dry weight-based forage yield was best estimated by a two-variable linear regression model made from the seasonal accumulated values of DMAT and DP. The estimated values from the models to the measured values were shown to have near 1 to 1 precision estimation, with the slopes of 0.9999 for fresh yield and 0.9961 for dry yield. Results also showed that fresh yield of forage was positively correlated with plant height at harvest, suggesting that the increased plant height would get a better forage production.

並列關鍵字

Nilegrass Acroceras macrum Stapf ； Climatic variable ； Forage production ； Plant height ； Multiple linear regression analysis