The SFM1 Sap Flow Meter is a self contained, stand-alone instrument for the measurement of sap flow or transpiration in plants. The SFM1 is a complete package containing sap flow sensors, data logger, interface software and internal battery which can be charged with an external solar panel. The SFM1 Sap Flow Meter is a new model which replaces the HRM30 sap flow measurement sensor.
Utilising the Heat Ratio Method (HRM) principle the SFM1 Sap Flow Meter is able to measure high, low and reverse flow rates in both small woody stems & roots as well as large trees. Like the Heat Field Deformation (HFD) principle, the HRM Sap Flow Meter is the only instrument that can measure zero flow and reverse sap flow rates. The SFM1 Sap Flow Meter is the most powerful and flexible instrument for the direct measurement of plant water use.
– SFT1 – Sap Flow Tool Software
– MCC1 – Wireless USB Radio communication device
– MCC2G – Remote Data Access Hub for Data To Web access via GSM
– SFM-SK1 – SFM Installation Kit
– SFM-55 – Pack of 10 Drill Bits
– SFM-TB – HRM block, Functional verification standard
– SP22 – 20 Watt Solar Panel and SPPM – Solar Panel Post Mount
|Output Options||Raw Temperatures: °C
Heat Pulse Velocity: cm hr-1
Sap Velocity: cm hr-1
Sap Flow: cm3 hr-1 (Litres hr-1)
|Range||-100 to +100 cm hr-1|
|Resolution||0.01 cm hr-1|
|Accuracy||0.5 cm hr-1|
|Measurement Duration||120 seconds|
|Computer Interface||USB, Wireless RF 2.4 GHz|
|Data Storage||MicroSD Card|
|Memory Capacity||Up to 16GB, 4GB MicroSD card included.|
|Heat Pulse||User Adjustable: 20 Joules (default) approx. Equivalent to a 2.5 second heat pulse duration, auto scaling.
User Adjustable: Minimum interval, 3 minutes, recommended minimum 10 minutes.
|Needle Diameter||1.3 mm|
|Needle Length||35 mm|
|Measurement Positions||2 per measurement needle|
|Measurement Spacings||7.5 mm and 22.5 mm from the needle tip|
|Dimensions L x W X D||170 x 80 x 35 mm|
|Internal Battery Specifications|
|960mAh Lithium Polymer, 4.20 Volts fully charged|
|External Power Requirements|
|Bus Power||8-30 Volts DC, non-polarised, current draw is 190mA maximum at 17 volts per logger|
|USB Power||5 Volts DC|
|Internal Charge Rate|
|Bus Power||60mA – 200mA Variable internal charge rate, maximum charge rate of 200mA active when the external voltage rises above 16 Volts DC|
|USB Power||100mA fixed charge rate|
|Internal Power Management|
|Fully Charged Battery||4.20 Volts|
|Low Power Mode||3.60 Volts – Instrument ceases to take measurements|
|Discharged Battery||2.90 Volts – Instrument automatically switches off at and below this voltage when no external power connected.|
|Battery Life varies|
Developed by the University of Western Australia and partner organisations, ICRAF and CSIRO, the HRM principle has been validated against gravimetric measurements of transpiration and used in published sap flow research since 1998. Burgess, S.S.O., et.al. 2001 An improved heat pulse method to measure low and reverse rates of sap flow in woody plants Tree Physiology 21, 589-598. Heat Ratio Method (HRM) is an improvement of the Compensation Heat Pulse Method (CHPM). Being a modified heat pulse technique power consumption is very low using approx 70 mAmp per day at a 10 minute temporal sampling interval under average transpiration rates. The HRM needles have two radial measurement points for the characterisation of radial sap flow gradients making measurements more accurate.
The SFM1 probes consist of three 35mm long needles integrally connected to a 16-bit microprocessor. The top and bottom probes contain two sets of matched and calibrated high precision thermistors located at 7.5mm and 22.5mm from the tip of each probe. The third and centrally located needle is a line heater that runs the full length of the needle to deliver a uniform and exact pulse of heat through the sapwood.
All aspects of the instruments operation and calculations are controlled by the microprocessor which automatically converts the analogue microvolt signals to a calibrated output. Programming variables such as heat pulse interval, energy input, probe spacings, and measurement frequency are all held resident in non-volatile memory. The HRM Sap Flow Meter displays information such as external battery status, Serial Number, firmware version, SD Card Status, Measurement interval, Data reporting options and correction factors. The utility software enables the Sap Flow Meter to be used in manual mode. This provides the ability to evaluate the efficacy of pulse intervals by viewing the raw measured temperatures on screen. Subsequent reports can then be viewed detailing the the duration of time the heat pulse required to deliver the exact amount of heat energy in Joules, the temperature rise following the previous heat pulse, temperature ratios between measurement points, sap velocity or sap flow.
Data can be manually processed using a spreadsheet program such as Excel to open the comma separated value (CSV) file provided by the Sap Flow Meter. More powerful and immediate processing can be achieved by directly importing the data file into the Sap Flow Tool Software. Thus providing instant 2 dimensional and 3D graphing of the raw heat pulse velocity and processing of sap velocity and sap flux. The entire data set can be instantly reprocessed if correction factors require modification or additional information becomes available.
The following papers either cite the SFM1 Sap Flow Meter or HRM30 Sensor on the SL-5 Smart Logger:
Ambrose, A. R., Sillett, S. C., Koch, G. W., Van Pelt, R., Antoine, M. E., & Dawson, T. E. (2010). Effects of height on treetop transpiration and stomatal conductance in coast redwood (Sequoia sempervirens). Tree Physiology. doi:10.1093/treephys/tpq064 http://treephys.oxfordjournals.org/content/early/2010/07/14/treephys.tpq064.full.pdf
Bleby, T. M., Burgess, S. S., & Adams, M. A. (2004). A validation, comparison and error analysis of two heat-pulse methods for measuring sap flow in Eucalyptus marginata saplings. Functional Plant Biology, 31(6), 645-658. http://www.publish.csiro.au/paper/FP04013.htm
Buckley, T. N., Turnbull, T. L., Pfautsch, S., & Adams, M. A. (2011). Nocturnal water loss in mature subalpine Eucalyptus delegatensis tall open forests and adjacent E. pauciflora woodlands. Ecology and evolution, 1(3), 435-450. http://onlinelibrary.wiley.com/doi/10.1002/ece3.44/pdf
Buckley, T. N., Turnbull, T. L., & Adams, M. A. (2012). Simple models for stomatal conductance derived from a process model: cross‐validation against sap flux data. Plant, cell & environment, 35(9), 1647-1662. http://onlinelibrary.wiley.com/doi/10.1111/j.1365-3040.2012.02515.x/abstract
Buckley, T. N., Turnbull, T. L., Pfautsch, S., Gharun, M., & Adams, M. A. (2012). Differences in water use between mature and post-fire regrowth stands of subalpine Eucalyptus delegatensis R. Baker. Forest Ecology and Management, 270, 1-10. http://www.sciencedirect.com/science/article/pii/S0378112712000114
Burgess, S. S., Adams, M. A., Turner, N. C., Beverly, C. R., Ong, C. K., Khan, A. A., & Bleby, T. M. (2001). An improved heat pulse method to measure low and reverse rates of sap flow in woody plants. Tree Physiology, 21(9), 589-598. http://treephys.oxfordjournals.org/content/21/9/589.full.pdf
Burgess, S. S. O., M. A. Adams, N. C. Turner, C. K. Ong, A. A. H. Khan, C. R. Beverly and T. M. Bleby (2001) Corrections: An improved heat pulse method to measure low and reverse rates of sap flow in woody plants. Tree Physiology, 21(16), 1157. doi:10.1093/treephys/21.16.1157 http://treephys.oxfordjournals.org/content/21/16/1157.full.pdf
Carbone, M. S., Park Williams, A., Ambrose, A. R., Boot, C. M., Bradley, E. S., Dawson, T. E., … & Still, C. J. (2013). Cloud shading and fog drip influence the metabolism of a coastal pine ecosystem. Global Change Biology, 19(2), 484-497. http://onlinelibrary.wiley.com/doi/10.1111/gcb.12054/abstract
De Groote, S. (2013). Impact of dew and rain on the water relations of the mangrove species Avicennia marina (Forssk.) Vierh (Doctoral dissertation, Master’s thesis, University Ghent, Faculty of Bioscience Engineering). Click to view Paper
Doronila, A. I., & Forster, M. A. (2015). Performance measurement via sap flow monitoring of three Eucalyptus species for mine site and dryland salinity phytoremediation. International journal of phytoremediation, 17(2), 101-108. http://www.tandfonline.com/doi/abs/10.1080/15226514.2013.850466#.UtdNuPtXepA
Downey A., Winter, W., Cull, P. (2013). Smart trees, smart kids – empowering a generation through the science of sap flow. ICT International. Downey et al Smart Trees Smart Kids – Empowering a Generation through the Science of Sap Flow
Drake, P. L., Coleman, B. F., & Vogwill, R. (2013). The response of semi‐arid ephemeral wetland plants to flooding: linking water use to hydrological processes. Ecohydrology, 6(5), 852-862. http://onlinelibrary.wiley.com/doi/10.1002/eco.1309/abstract
Eller, C. B., Lima, A. L., & Oliveira, R. S. (2013). Foliar uptake of fog water and transport belowground alleviates drought effects in the cloud forest tree species, Drimys brasiliensis (Winteraceae). New Phytologist, 199(1), 151-162. http://onlinelibrary.wiley.com/doi/10.1111/nph.12248/pdf
Falge, E., & Meixner, F. X. (2008). Validation of a 3D gas exchange model for a Picea abies canopy in the Fichtelgebirge, Germany. In Geophys. Res. Abstr (Vol. 10). Download PDF.
Fuchs, S., Leuschner, C., Link, R., Coners, H., Schuldt, B. (2017). Calibration and comparison of thermal dissipation, heat ratio and heat field deformation sap flow probes for diffuse-porous trees. Agricultural and Forest Meteorology. https://doi.org/10.1016/j.agrformet.2017.04.003
Forster, M. A. (2012). Quantifying water use in a plant–fungal interaction. Fungal Ecology, 5(6), 702-709. http://dx.doi.org/10.1016/j.funeco.2012.06.005
Gharun, M., Turnbull, T. L., & Adams, M. A. (2013). Stand water use status in relation to fire in a mixed species eucalypt forest. Forest Ecology and Management, 304, 162-170. http://dx.doi.org/10.1016/j.foreco.2013.05.002
Gharun, M., Turnbull, T. L., Pfautsch, S., & Adams, M. A. (2015). Stomatal structure and physiology do not explain differences in water use among montane eucalypts. Oecologia, 177(4), 1171-1181. http://link.springer.com/article/10.1007%2Fs00442-015-3252-3
Mitchell, P. J., Veneklaas, E., Lambers, H., & Burgess, S. S. (2009). Partitioning of evapotranspiration in a semi-arid eucalypt woodland in south-western Australia. Agricultural and Forest Meteorology, 149(1), 25-37. http://www.sciencedirect.com/science/article/pii/S0168192308002050
Palmer, A. R., Fuentes, S., Taylor, D., Macinnis‐Ng, C., Zeppel, M., Yunusa, I., & Eamus, D. (2010). Towards a spatial understanding of water use of several land‐cover classes: an examination of relationships amongst pre‐dawn leaf water potential, vegetation water use, aridity and MODIS LAI. Ecohydrology, 3(1), 1-10. http://onlinelibrary.wiley.com/doi/10.1002/eco.63/abstract
Patankar, R., Quinton, W. L., Hayashi, M., & Baltzer, J. L. (2015). Sap flow responses to seasonal thaw and permafrost degradation in a subarctic boreal peatland. Trees, 29(1), 129-142. http://link.springer.com/article/10.1007/s00468-014-1097-8
Pfautsch, S., Dodson, W., Madden, S., & Adams, M. A. (2015). Assessing the impact of large‐scale water table modifications on riparian trees: a case study from Australia. Ecohydrology, 8(4), 642-651. PDF
Pfautsch, S., Keitel, C., Turnbull, T. L., Braimbridge, M. J., Wright, T. E., Simpson, R. R., … & Adams, M. A. (2011). Diurnal patterns of water use in Eucalyptus victrix indicate pronounced desiccation–rehydration cycles despite unlimited water supply. Tree physiology, 31, 1041-1051. doi:10.1093/treephys/tpr082 http://treephys.oxfordjournals.org/content/31/10/1041.full.pdf+html
Pfautsch, S., Peri, P. L., Macfarlane, C., van Ogtrop, F., & Adams, M. A. (2014). Relating water use to morphology and environment of Nothofagus from the world’s most southern forests. Trees, 28(1), 125-136.
Resco de Dios, V., Díaz‐Sierra, R., Goulden, M. L., Barton, C. V., Boer, M. M., Gessler, A., … & Tissue, D. T. (2013). Woody clockworks: circadian regulation of night‐time water use in Eucalyptus globulus. New Phytologist, 200(3), 743-752. http://onlinelibrary.wiley.com/doi/10.1111/nph.12382/abstract
Rosado, B. H., Oliveira, R. S., Joly, C. A., Aidar, M. P., & Burgess, S. S. (2012). Diversity in nighttime transpiration behavior of woody species of the Atlantic Rain Forest, Brazil. Agricultural and forest meteorology, 158, 13-20. http://www.sciencedirect.com/science/article/pii/S0168192312000536
Staudt, K., Serafimovich, A., Siebicke, L., Pyles, R. D., & Falge, E. (2011). Vertical structure of evapotranspiration at a forest site (a case study). Agricultural and forest meteorology, 151(6), 709-729. http://www.sciencedirect.com/science/article/pii/S0168192310002844
Van de Wal, B. A., Guyot, A., Lovelock, C. E., Lockington, D. A., & Steppe, K. (2015). Influence of temporospatial variation in sap flux density on estimates of whole-tree water use in Avicennia marina. Trees, 29(1), 215-222. http://link.springer.com/article/10.1007/s00468-014-1105-z
Yang, L., Miki, N. H., Matsuo, N., Zhang, G., Wang, L., & Yoshikawa, K. (2014). Contribution of adventitious roots to water use strategy of Juniperus sabina in a semiarid area of China. Journal of Agricultural Science and Technology. A, 4(3A), 251-259. http://www.davidpublishing.com/davidpublishing/Upfile/6/2/2014/2014060267931369.pdf
Zeppel, M. J., Lewis, J. D., Medlyn, B., Barton, C. V., Duursma, R. A., Eamus, D., … & Tissue, D. T. (2011). Interactive effects of elevated CO2 and drought on nocturnal water fluxes in Eucalyptus saligna. Tree physiology, 31(9), 932-944. http://treephys.oxfordjournals.org/content/31/9/932.full.pdf+html