甘蔗需水量及土壤墒情评价指标体系研究

摘要

Evaluation index system of soil moisture is the basis for crop irrigation, this article analysed nearly 10 years of meteorological data in Leizhou peninsula, the main sugarcane producing areas in Guangdong. Using the crop coefficient method estimated water requirement (ETc) and its variation of sugarcane, which is recommended by FAO. The results showed that different growth periods of crop water requirement in sugarcane was different and the whole growth period was about 968.32 mm. Water requirement and absorption per day in elongation period was the largest, which was 581.13 mm and 4.47 mm/d. The peak of water requirement (149.8 mm) of sugarcane per month was in July while the early growth stage was lager while the remainder stage was lesser. The suitable soil moisture content of sugarcane in different growth period was analyzed and summarized, accordingly established the soil moisture evaluation index system of sugarcane with different texture soil in Guangdong. The field experiment showed that the index system was reasonable, which could guide local irrigation and soil moisture monitoring of sugarcane in Guangdong.%土壤墒情评价是作物科学灌溉的基础.本文基于广东甘蔗主产区雷州半岛近10年的气象资料,采用FAO推荐的作物系数法估算了甘蔗需水量(ETc)及其变化规律.结果表明,甘蔗全年需水量为968.32 mm;不同生育期需水量不同,以伸长期需水量和日吸水强度最大,分别为581.13 mm和4.47 mm/d;生长前期和后期需水量较小,而生长中期需水量较大,月需水量顶峰出现在7月份,达149.8 mm.确定了甘蔗不同生育阶段适宜的土壤含水率和土层湿润深度,结合甘蔗主产区典型土壤质地类型,初步建立了不同质地土壤相对应的墒情评价指标体系.田间试验表明,该指标体系科学合理,可作为粤西蔗区土壤墒情监测评价及农田水分精准管理的依据.