Next Article in Journal
Environmental Controls of Diurnal and Seasonal Variations in the Stem Radius of Platycladus orientalis in Northern China
Previous Article in Journal
Quantifying the Relationship among Impact Factors of Shrub Layer Diversity in Chinese Pine Plantation Forest Ecosystems
Open AccessArticle

Scaling Up Sap Flow Measurements from the Stem Scale to the Individual Scale for Multibranched Caragana Korshinskii on the Chinese Loess Plateau

by 1,2,3, 1,2,3,*, 1,2,3, 1,2,3 and 4
1
State Key Laboratory of Grassland Agro-Ecosystems, Lanzhou University, Lanzhou 730020, China
2
Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Lanzhou University, Lanzhou 730020, China
3
Engineering Research Center of Grassland Industry, Ministry of Education, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730020, China
4
Institute of Ecological Management of the Loess Region, Gansu Academy of Forestry Sciences, Lanzhou 730000, China
*
Author to whom correspondence should be addressed.
Forests 2019, 10(9), 785; https://doi.org/10.3390/f10090785
Received: 13 July 2019 / Revised: 30 August 2019 / Accepted: 4 September 2019 / Published: 9 September 2019
(This article belongs to the Section Forest Ecology and Management)
The traditional heat balance method for measuring plant sap flow (SF) becomes troublesome and uneconomic for multibranched shrub species if all their stems are used for the measurement. The objectives of this study were to explore specific relationships between stem-scale SF and plant morphological traits and then to scale up SF measurements from the stem scale to the individual scale for Caragana korshinskii Kom., a dominant shrub species on the Chinese Loess Plateau. Sap flow was measured for twenty-one stems from three representative individuals from July to September 2018 during the rainy season. The results indicated that the stem-scale SF in C. korshinskii presented a positive linear correlation with the stem base diameter (SBD), stem length (SL), primary branch numbers in the stem (PBN), and estimated stem biomass (W). The SBD-based statistical models performed well in estimating the stem-scale SF, with an R2 value of 0.9726 and root mean squared error (RMSE) of 2.5389 g h−1. Over the canopy projection area, the individual-scale transpiration flows for the three selected C. korshinskii were 1.91, 1.10, and 1.59 mm·d−1. In addition, stem-scale SF was positively and linearly correlated with air temperature, photosynthetically active radiation, vapor pressure deficit, reference crop evapotranspiration, and variable transpiration. This study sheds light on morphological and meteorological influences on stem-scale SF and has made contributes to the accurate and rapid estimation of the plant sap flow from easily available morphological traits for multibranched shrub species in semiarid regions. Limitations, however, may exist for the established model when it is used to estimate SF of C. korshinskii during the water-limited dry season. Our study deserves further exploration of a more general model to have a better estimation of SF for C. korshinskii in both dry and rainy seasons. View Full-Text
Keywords: sap flow; morphological traits; meteorological factor; stem scale; individual scale sap flow; morphological traits; meteorological factor; stem scale; individual scale
Show Figures

Figure 1

MDPI and ACS Style

Wang, G.; Shen, Y.; Yang, X.; Chen, Z.; Mo, B. Scaling Up Sap Flow Measurements from the Stem Scale to the Individual Scale for Multibranched Caragana Korshinskii on the Chinese Loess Plateau. Forests 2019, 10, 785.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map

1
Back to TopTop