CALIBRATION OF THE THERMAL DISSIPATION PROBE FOR ATEMOYA: (Annona squamosa x A. cherimola)

ABSTRACT When determining plant transpiration (TR) using the thermal dissipation probe method, it is necessary to calibrate the sap flow (SF) estimation equation for each species under study, and thus obtain reliable information about the water demand of crops. This study aims to calibrate the equation used to determine SF using the thermal dissipation probe for atemoya cultivation. The experiment was conducted in the experimental field of the Universidade do Estado da Bahia, Juazeiro, Northeast Brazil. Atemoya plants in the initial phase of development were transplanted into 21.5-l pots arranged on weighing platforms that acted as lysimeters. The SF was determined by the thermal dissipation probe method using 1-cm-long probes. The angular coefficient of the Granier equation was adjusted by minimizing the absolute deviations between the accumulated daily SF and TR measured using the lysimeter. The results demonstrated that the application of the Granier method is satisfactory for estimating the TR of the atemoya and that it is necessary to adjust the angular coefficient of the equation. The mean absolute error between SF and TR was 3.1%.

摘要：在利用热消散探针法（thermal dissipation probe method）测定植物蒸腾量（TR）时，需针对每一种研究物种校准树液流量（SF）估算方程，从而获得可靠的作物需水信息。本研究旨在针对阿蒂莫耶（atemoya）种植场景，校准采用热消散探针法测定树液流量的相关方程。实验于巴伊亚州立大学（Universidade do Estado da Bahia）位于巴西东北部茹阿泽鲁的试验田内开展。将处于生长初期的阿蒂莫耶植株移栽至21.5升容量的盆钵中，盆钵安置于充当蒸渗仪（lysimeter）的称重平台上。采用1厘米长的探针，通过热消散探针法测定树液流量。通过最小化累积日树液流量与蒸渗仪测得的植物蒸腾量之间的绝对偏差，对Granier方程（Granier equation）的角系数进行校正。结果表明，Granier法在估算阿蒂莫耶植株蒸腾量方面表现良好，且有必要对该方程的角系数进行调整。树液流量与蒸腾量之间的平均绝对误差为3.1%。