When to irrigate for sugar cane (Department of Agricultural Engineering)
| Autor: | Yamashiro, Saburo |
|---|---|
| Jazyk: | japonština |
| Rok vydání: | 1989 |
| Zdroj: | 琉球大学農学部学術報告 = The Science Bulletin of the Faculty of Agriculture. University of the Ryukyus. 36:73-87 |
| ISSN: | 0370-4246 |
| Popis: | 本研究は,ポット試験によってサトウキビに対するかんがい開始時期について検討するものである。上記の目的を達成するために,サトウキビの蒸散流速,蒸散量,土壌水分および土壌の水分張力(pF)を測定し,これらの相互関係について調べた。さらに,蒸散流速および蒸散量の時間変化と気象要因との関係についても検討した。その結果,蒸散流速,蒸散量,土壌水分および土壌の水分張力の変動からサトウキビに対するかんがい開始の時期としては土壌の水分張力がpF3.7∿pF3.8になった場合が適当であることがわかった。蒸散流速はこのpF値付近においてはほぼ一定の値となった。また,蒸散流速および蒸散量の時間変化と気象要因の関係から,蒸散流速は蒸散量の指標として,十分役立つことがわかった。このようにして蒸散流速をモニタリングすることによって,サトウキビがいつ水分欠乏をきたし,いつかんがいすべきであるかを知ることが可能である。 This study was done in order to investigate when to irrigate for sugar cane. The sugar cane which was used in this test was planted in pots. To attain this purpose, sap flow velocity and transpiration of sugar cane, soil moisture and soil moisture tension were measured. I investigated the relationship bitween them. Between sap flow velocity, the mean value of hourly transpiration rate and weather were also investigated. It became clear that a daily monitoring of sap flow velocity, transpiration rate, soil moisture content and soil moisture tension indicated that sugar cane needs to be irrigated whenever the soil moesture tension reaches a pF value between 3.7 and 3.8. From these pF value, the sap flow velocity became nearly constant. From the observation made, it seemed clear that both the sap flow velocity and the transpiration rate were equally influenced by the weather. It also appeared evident that sap flow velocity could serve quite well as an index of transpiration rate. Thus by monitoring sap flow velocity, it could be possible to tell when the sugar cane plants are experiencing water stress and thus requireing further water application. 紀要論文 |
| Databáze: | OpenAIRE |
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