添加生物炭對酸性紅壤肥力之影響

Effects of Application of Biochar on Soil Fertility of Acidic Red Soils

簡士濠(Shih-Hao Jien) ； 江介倫(Jie-Lun Chiang) ； 王建昇(Chien-Sen Wang) ； 張庠睿(Hsiang-Jui Chang)

《農業工程學報》 58卷4期 (2012/12) Pp. 15-22

https://doi.org/10.29974/JTAE.201212.0002

摘要

紅壤為臺灣地區重要耕作土壤之一。長期的耕犁與過量使用化學肥料造成土壤的酸化與嚴重退化，故永續維持土壤品質與產量為目前農業迫切課題之一。本研究主要利用林業廢棄物—銀合歡木材於厭氧高溫下燒製成之生物炭，添加至酸性紅壤中，孵育3個月，以評估添加生物炭對紅壤肥力之改善與不同添加量下土壤養分之動態變化。實驗結果顯示酸性紅壤經添加5%生物炭後，土壤pH值顯著由4.0提升至5.1、有機碳含量顯著增加至少7.0g kg^(-1)，而鹽基飽和度顯著增加2倍以上，且增加幅與生物炭添加量呈正相關。此外，土壤經改良後，土壤微生物活性以5%添加量顯著最高，且隨時間漸達穩定平衡；土壤中可交換性氮與有效磷含量亦隨生物炭添加而顯著增加，同樣以5%施用量下所增加之幅度最高。然而，可交換性氮與有效磷皆隨孵育期間的降雨淋洗而損失，以未改良土壤之損失比率最高。整體而言，施用生物炭至酸性紅壤中，不僅可有效改善土壤品質，亦可達到保持土壤肥力的效用。

關鍵字

紅壤 ； 生物炭 ； 土壤肥力 ； 可交換性氮 ； 有效磷

並列摘要

Red soil is an important rural soil in Taiwan. Long-term cultivation and unsuitable chemical fertilizer application accelerate soil degradation. Therefore, sustainable maintenance of soil quality and crop productivity is an urgent issue for agriculture now. This study used a forestry waste, woods of white leadtree (Leucaena leucocephala (Lam.) de Wit), to prepare a wood biochar as an soil amendment, which was incorporated into the acicic red soils for 3 months incubation. This study aimed to evaluate the variation of soil fertility and the dynamic changes of nutrients. The experimental results indicated that applying biochar into the soil significantly increased soil pH from 4.0 to 5.1, organic carbon contents increased at least 7.0 g kg^(-1) and base saturation percentages were 2 times at least than those of un-amended soils. Furthermore, microbial biomass carbon, exchangeable nitrogen and available phosphorous contents were also increased with increasing applying rate of biochar. The increasing amounts of mentioned-above properties were positively related to applying rates of biochar. As a whole, applying biochar into the red soil could improve soil qualities and retain soil fertility efficiently.

並列關鍵字

Red soil ； biochar ； soil fertility ； exchangeable nitrogen ； available phosphorous