陡坡地芒果園百喜草覆蓋及敷蓋之研究

Study on Bahia Grass Covering and Mulching for Mango Orchards on Steep Slopeland

鄭慶生(C. S. Cheng)

《中華農業研究》 41卷1期 (1992/03) Pp. 70-78

https://doi.org/10.29951/JARC.199203.0008

摘要

本試驗之目的在比較陡坡地芒果園百喜草不同覆蓋及敷蓋方式對水土及地表養份流失、土壤理化性質和芒果生育等影響情形，以明瞭百喜草覆蓋及敷蓋方法在陡坡地芒果園中之坡度限制及其水土保持效益，並確立陡坡地芒果園最經濟有效的水土保持方法，期提供陡坡地芒果園土壤管理和保育設計參考作為推廣之依據。本試驗包括四個處理：（一）百喜草全園覆蓋及敷蓋；（二）百喜草帶狀覆蓋及敷蓋；（三）清耕區；（四）對照區（未種植芒果）。茲將試驗結果摘要如下：
（一）各處理水土流失測定結果均以百喜草全園覆蓋及敷蓋處理區較低，百喜草帶狀覆蓋及敷蓋處理區次之，二者之間差異不顯著，而以清耕區及對照區較高，均與前二處理區呈極顯著的差異。各處理地表逕流水中養份流失量和各處理水土流失量大小趨勢相同。逕流水中養份濃度以施肥後較高。
（二）根據土壤團粒體積中數粒徑、分散率、飽和導水率、假比重、孔隙率、滲透率及保水特性等各項測定結果顯示：百喜草覆蓋部份之土壤物理性較佳。土壤有機質含量以百喜草覆蓋部份較高，土壤交換性鉀及有效磷含量則以百喜草敷蓋部份較高。清耕區及對照區土壤理化性均較差，因水土及養份嚴重流失所致。
（三）旱季各處理土壤水分測定結果，以百喜草敷蓋部份較高，清耕區及對照區較低。雨季各處理土壤水分含量則以百喜草覆蓋部份較高，仍以清耕區及對照區較低。
（四）百喜草全園或帶狀覆蓋及敷蓋處理區之覆蓋情形良好，覆蓋率均達90%以上。
（五）各處理芒果生育調查結果，以百喜草帶狀覆蓋及敷蓋處理較佳，清耕區較差。
（六）綜上所述，在與本試驗各項條件近似的25°陡坡地芒果園於山邊溝間距範圍內採用百喜帶狀覆蓋及敷蓋處理，兼具覆蓋與敷蓋的優點，能有效控制水土及養份流失，減少旱季土壤水分之蒸發，且有利於土壤理化性質之改善及芒果之生育，為理想的陡坡芒果園經濟有效的水土保持方法。

關鍵字

陡坡地 ； 芒果園 ； 百喜草 ； 覆蓋 ； 敷蓋

並列摘要

The purpose of this experiment is to find out the effect of bahia grass covering and mulching on soil and water loss, on soil physical and chemical properties, and on mango growth for finding the most effective and economical method of soil conservation in steep mango orchards. The results obtained are summarized as follows:
1. The trearments of covering and mulching with bahia grass and stripping and mulching with bahia grass hab the minimum soil and water loss, whereas the control plot had the maximum.
2. The median diameter of aggregates, bulk specific gravity, dispersion ratio, porosity, and hydraulic conductivity of the soil were found to be the best in bahia grass covering treatments. The amount of organic matter was the highest in bahia grass covering treatments. Bahia grass mulching treatments increased available P and exchangeable K.
3. During the dry season, soil moisture content in the treatment of stripping and mulcheing with bahia grass was higher than that of in amy other treatnent.
4. Best coverage was observed in the treatments of covering and mulcheng with bahia grass and stuipping and mulchein with bahia grass because of vigor growth of bahia grass.
5. The treatment of stripping and mulching with bahia grass gives the best mango growth.
6. Based on the aforementioned results, the treatment of stripping and mulcging with bahia grass could effectively control the soil and water loss, reduce evaporation loss of soil moisture, improve soil physical and chemical properties, and provide full coverage and excellent effect for soil conservation. Therefore, for steep mango orchards the most effective and economical conservation practice is to combine this treatment with hillside ditching.

並列關鍵字

Steep slopeland ； Mango orchards ； Bahia grass ； Covering ； Mulching