נגישות
menu      
חיפוש מתקדם
תחביר
חפש...
הספר "אוצר וולקני"
אודות
תנאי שימוש
ניהול
קהילה:
אסיף מאגר המחקר החקלאי
פותח על ידי קלירמאש פתרונות בע"מ -
Improvement of the heat pulse method for determining sap flow in trees
Year:
1981
Source of publication :
Plant, Cell & Environment
Authors :
כהן, יחזקאל
;
.
פוקס, מרסל
;
.
Volume :
4
Co-Authors:
COHEN, Y., Institute of Soils and Water, Agricultural Research Organization, Volcani Center, Bet Dagan, Israel
FUCHS, M., Institute of Soils and Water, Agricultural Research Organization, Volcani Center, Bet Dagan, Israel
GREEN, G.C., Soil and Irrigation Research Institute, Pretoria, South Africa
Facilitators :
From page:
391
To page:
397
(
Total pages:
7
)
Abstract:
Abstract. The heat pulse method for determining sap flux in large woody sterns was modified for easier field operation. It uses the measurement of the time elapsed between heat pulse release by a line heater radially inserted in the stem, and the occurrence of maximum temperature 15 mm downstream of the heater. This spacing between heater and thermometer is critical to the reliability of the measurement. Calculations using uncorrected theory provide estimates of the sap flux density in stems with both uniform and non‐uniform cross‐sectional distribution of conducting tissues which are about 55% of the actual sap flux density. This factor results from insufficient thermal homogeneity between tissues where sap flow occurs and tissues where sap flow has been interrupted. Sap flow in trunks of citrus trees was inferred from measurements of the cross‐sectional distribution of sap flux density. Variability of sap flux density is specific to each trunk and is time‐dependent and imposes multiple radial and angular measurements. The method was checked in a citrus trunk ramified into three branches. Instantaneous determinations of the flow in the trunk and in the branches differed by less than 5.7%. The daily values agreed within 2.8%. Copyright © 1981, Wiley Blackwell. All rights reserved
Note:
Related Files :
Citrus sinensis L. Osbeck
head conduction
plane
Platanaceae
Platanus orientalis L.
poplar
Salicaceae
transpiration
עוד תגיות
תוכן קשור
More details
DOI :
10.1111/j.1365-3040.1981.tb02117.x
Article number:
Affiliations:
Database:
סקופוס
Publication Type:
מאמר
;
.
Language:
אנגלית
Editors' remarks:
ID:
19918
Last updated date:
02/03/2022 17:27
Creation date:
16/04/2018 23:32
Scientific Publication
Improvement of the heat pulse method for determining sap flow in trees
4
COHEN, Y., Institute of Soils and Water, Agricultural Research Organization, Volcani Center, Bet Dagan, Israel
FUCHS, M., Institute of Soils and Water, Agricultural Research Organization, Volcani Center, Bet Dagan, Israel
GREEN, G.C., Soil and Irrigation Research Institute, Pretoria, South Africa
Improvement of the heat pulse method for determining sap flow in trees
Abstract. The heat pulse method for determining sap flux in large woody sterns was modified for easier field operation. It uses the measurement of the time elapsed between heat pulse release by a line heater radially inserted in the stem, and the occurrence of maximum temperature 15 mm downstream of the heater. This spacing between heater and thermometer is critical to the reliability of the measurement. Calculations using uncorrected theory provide estimates of the sap flux density in stems with both uniform and non‐uniform cross‐sectional distribution of conducting tissues which are about 55% of the actual sap flux density. This factor results from insufficient thermal homogeneity between tissues where sap flow occurs and tissues where sap flow has been interrupted. Sap flow in trunks of citrus trees was inferred from measurements of the cross‐sectional distribution of sap flux density. Variability of sap flux density is specific to each trunk and is time‐dependent and imposes multiple radial and angular measurements. The method was checked in a citrus trunk ramified into three branches. Instantaneous determinations of the flow in the trunk and in the branches differed by less than 5.7%. The daily values agreed within 2.8%. Copyright © 1981, Wiley Blackwell. All rights reserved
Scientific Publication
You may also be interested in