系統(tǒng)功能

采用熱擴(kuò)散技術(shù)測量植物莖干莖流速度，特別適用于莖干較粗的樹木和高大植物。若配合其它傳感器使用，可測量環(huán)境因子（空氣溫濕度，光合有效輻射、土壤溫濕度等）影響下的植物莖流。

工作原理

利用Granier熱擴(kuò)散傳感器（TDP）原理，把2根熱電偶探針直接插入邊材，上面的探針包含1個電加熱器，下面的探針作為參照，測量加熱探針和參照探針之間的溫差dT。根據(jù)dT和零莖流時的dTm，應(yīng)用Granier模型，可以直接得到每個時刻的莖流速率，再根據(jù)邊材面積求出莖流通量。

對于郁閉冠層下長勢一致的樹木，每棵樹只需一個傳感器。對于不規(guī)則冠層或混合樹種，大樹的莖流速率在樹周不同方向上存在差異，一棵樹需要使用多個傳感器才能準(zhǔn)確測量莖流。直徑在75~150 mm的樹木，每棵樹通常需安裝2套傳感器；直徑在150~440 mm的樹木，每棵樹安裝4套傳感器。

系統(tǒng)特點(diǎn)

雙探針，Granier磚利設(shè)計

探針易插拔，可重復(fù)使用

恒溫加熱，采用熱擴(kuò)散方法，而不是準(zhǔn)確度較差的熱脈沖方法

可以連續(xù)測量（熱脈沖方法不可以，有等待周期）

應(yīng)用案例

（1）西北農(nóng)林科技大學(xué) 秦嶺

參考文獻(xiàn)

1 Amani, B., B. Olfa, et al. (2013). "COMPARISON BETWEEN SAP FLOW MEASUREMENTS AND TWO PREDICTION CLIMATE FORMULAS TO ESTIMATE TRANSPIRATION IN OLIVE ORCHARDS (OLEA EUROPAEA L. CV. CHEMLALI)." European Scientific Journal 9(21).

2.Duberstein, J. A., K. W. Krauss, et al. (2013). "Do Hummocks Provide a Physiological Advantage to Even the Most Flood Tolerant of Tidal Freshwater Trees?" Wetlands: 1-10.

3.Ferro, A. M., T. Adham, et al. (2013). "Performance of deep-rooted phreatophytic trees at a site containing total petroleum hydrocarbons." International Journal of Phytoremediation 15(3): 232-244.

4.Juzwik, J., J.-H. Park, et al. (2013). Biotic agents responsible for rapid crown decline and mortality of hickory in northeastern and north central USA. Proceedings of the 18th Central Hardwoods Forest Conference GTR-NRS-P.

5.Park, J.-H., J. Juzwik, et al. (2013). "Multiple Ceratocystis smalleyi infections associated with reduced stem water transport in bitternut hickory." Phytopathology 103(6): 565-574.

6.Pinto Jr, O. B., G. L. Vourlitis, et al. (2013). "Transpiration by the heat dissipation probe method in transition Amazon-Savannah forest." Revista Brasileira de Engenharia Agrícola e Ambiental 17(3): 268-274.

7.Sullivan, P. L., V. Engel, et al. (2013). "The influence of vegetation on the hydrodynamics and geomorphology of a tree islａnd in Everglades National Park (Florida, United States)." Ecohydrology.

8.Zhang, Y., Y. Shen, et al. (2013). "Characteristics of the water–energy–carbon fluxes of irrigated pear ( Pyrus bretschneideri Rehd ) orchards in the North China Plain." Agricultural Water Management 128: 140-148.

9.Zhou, Y., J. Wenninger, et al. (2013). "Groundwater–surface water interactions, vegetation dependencies and implications for water resources management in the semi-arid Hailiutu River catchment, China–a synthesis." Hydrology and Earth System Sciences 17(7): 2435-2447.

10.趙曉偉, 趙平, et al. (2013). "木荷樹干夜間水分補(bǔ)充的季節(jié)動態(tài)及其與樹形特征和葉片生物量的關(guān)系." 植物生態(tài)學(xué)報 37(3): 239-247.