坡地柑桔園土壤水分及營養管理技術改進

Technical Improvement of Soil Moisture & Nutrition Management on the Slope Land of Citrus Orchards

黃和炎(H. Y. Huang) ； 呂俊堅(C. J. Leu)

《臺南區農業改良場研究彙報》 27期 (1991/12) Pp. 17-24

https://doi.org/10.29558/XLZY.199112.0003

摘要

據調查南部坡地果園，一般土壤有機質含量極端缺乏（0.7～1.5%），土壤呈強酸性反應（pH4.0～5.2），缺少灌溉設施，水土保持不盡理想，導致表土容易流失。新化分場之土壤甚具代表性，因而選擇一公頃五年生柳橙園進行試驗，經二年結果摘述如下：（一）、省產滴灌器材每公頃設施費用在60,000元左右，尚可被果農接受，惟滴頭缺點尚多，如容易阻塞及流量不均勻等，須再改善。（二）、滴水表面滲透半值約10～15公分，而呈90度之扇狀向下分佈，深達1公尺，達到根系之吸收範圍。（三）、在乾旱期每棵果樹每次滴灌60～80公升／10小時，維持在-0.3～-0.5bar以內，其滴灌期距約7~20天。（四）、台肥之液體肥料滴施濃度宜稀釋300倍，較人工施用固體肥料（穴施或條施），可節省人工費用約3,000元／公頃／次。（五）、施用有機肥料30公斤／棵／年，土壤有機質含量顯著增加，而施用2公斤石灰石粉，半年內維持較高之土壤反應，而後漸次恢復。（六）、灌溉區之果樹生長速度其樹幹直徑較無灌溉區第一年無顯著差異，第二年增加11.3%，單粒果實重量增加14%，糖份增加0.7Brix。酸度略降。

關鍵字

坡地果園 ； 土壤水分 ； 營養管理

並列摘要

In general, the soil of slope land orchards in southern Taiwan are low in organic matter (0.7~ 1.5%), low in pH value (4.0~ 5.2) and lack of irrigation facilities which resulted in a very serious problem of soil erosion. Soil & water conservation was also poor. Because the soil of Hsinhua Branch station is very typical, one hectare of a 5-yr old orchard of sweet orange was used in this study for the improvement of irrigation and fertilizer application system. The results from 1987 and 1990 are summarized as follow: (I)The cost of the dripping irrigation system is ca. NT$60,000 dollars/ha which is acceptable to most of the farmers, however, the nozzle and uneven flow rate in the pipes should be improved. (2) The diffusion area of water on the soil surface was 10~ 15 cm in diameter, and the water moved vertically in a sector shape downward to 1 meter in depth. (3)During the dry season, if the dripping irrigation condition controlled at 60~80 litres/tree/10 hrs, the water optential in the soil can aintain between -0.3~-0.5 bar in 7~20 days. (4)When the iiquid fertilzer of Taiwan Fertilizer Co. (300 dilutions) was mixed into the fertigation system, the application cost of labor reduced. NT$3,000 dollars/ha/time, comparing to the hand application of solid fertilizers. (5) Application of organic fertilizer at the rate of 30kg tree/yr signicantly increased the organic matter content of the soil, and the application of calaium carbonate powder at the rate of 2kg/tree can maintined the soil at high pH value condition in 6 months and then return to the original level. (6) The trunk diameter of the dripped trees incresed 11.3% in 2nd year, fruit weight increased 14%, sugar content increased 0.7 Brix and acidity decreased.