摘要
雨养桑园是指桑树生长发育所需的水全部来源于降水,即桑树全部需水靠桑园土壤将降水蓄积保持后较均匀地供给桑树。选择土壤肥沃、光热资源丰富,但降水分布不均的川南山区宁南县作为试验点,调查雨养桑园水分的供需情况,为桑树的水分管理和桑园灌溉提供依据。试验区的桑树需水量最大的时期在每年的4～5月份,但这一时段的降雨稀少,桑园土壤水分亏缺严重,尤其是4月上旬～5月中旬,桑园中桑树的水分订正系数<0.50的频率高达67%～95%,需要人工灌溉。5月下旬后,随着降水量增加,桑园土壤水分状况变好,不再需要灌溉。调查结果表明,试验区桑园土壤是一个巨型水库,有效水库容随土壤厚度增加而增加,厚度300 cm的桑园土壤有效水库容达300 mm左右,为桑树年需水量的1/3,因而保证桑园有深厚的土壤将对桑树水分的供给和调控产生重要作用,有利于桑叶优质高产和稳产。
A rainfed mulberry filed means that all water required for mulberry growth and development comes from precipitation,that is,all demand of mulberry trees on water relies on the filed soil to retain and conserve rainfall for a relatively even water supply to mulberry trees.The present study selected Ningnan County in southern mountain areas of Sichuan Province as the test site.This area is typified by fertile soil,rich light and heat resources,but uneven distribution of precipitation.Water supply and demand of rainfed mulberry field at this site was investigated to provide guidance for water management and irrigation in mulberry field.At the test site,the highest demand of water by mulberry trees was from April to May each year.But the precipitation was very scarce in this period and water deficiency was very severe in mulberry field.Especially in early April to mid-May,the frequency of moisture correction coefficient below 0.50 was as high as 67% to 95%,being necessary to have artificial irrigation.From late May,with the increase of precipitation,water status in mulberry filed was improved and irrigation was no longer necessary.Our survey revealed that soil of mulberry field at the test site was a huge water bank,of which the available water capacity increased with soil thickness.When the soil thickness reached 300 cm,its available water capacity could be up to about 300 mm,which accounted for about 1/3 of annual water demand of mulberry trees.Therefore,to ensure sufficient soil thickness of mulberry field is of great significance on water supply and regulation in mulberry field and is conducive for stable production of high yield and high quality mulberry leaves.
出处
《蚕业科学》
CAS
CSCD
北大核心
2012年第6期988-993,共6页
ACTA SERICOLOGICA SINICA
基金
现代农业产业技术体系专项(No.CARS-22)
关键词
桑树
雨养
桑园土壤
蒸发蒸腾量
有效水库容量
Morus L.
Rainfed
Mulberry soil
Evapotranspiration
Available water capacity
