The relationships between water storage and biomass components in two conifer species.

Lai Zhou,Yujun Sun,Muhammad Amir,Zhaohui Li,Bo Zhang,Mi Luo,Sajjad Saeed

doi:10.7717/peerj.7901

Abstract

BackgroundWater storage is a significant physiological index of vegetation growth. However, information on water storage at the individual tree level and its relationship to climatic conditions and productivity is scarce.MethodsWe performed a comparative analysis of water storage using field measurements acquired three age classes of Chinese fir (Cunninghamia lanceolata) and Korean larch (Larix olgensis). The distributions of water storage, water content ratio and dry mass were presented, and regression analyses were used to confirm the relationships of water storage and water content ratio to dry mass components, respectively.ResultsOur results indicated that water was mostly concentrated in the stem xylem, which aligned well with the distribution of dry mass in both conifer species. However, the water storage of the stem xylem was always higher in Chinese fir than in Korean larch. The average water content ratio of both conifer species decreased with age, but that of Chinese fir was always higher than that of Korean larch. There was a significant difference in the water storage proportion in the components of Chinese fir (P < 0.001) and Korean larch (P < 0.001). The effects of age class on the water storage of Chinese fir (P = 0.72) and Korean larch (P = 0.077) were not significant. Interestingly, significant positive linear correlations were found between fine root water and leaf water and mass in Chinese fir (P < 0.001, R2 ≥ 0.57) and Korean larch (P < 0.001, R2 ≥ 0.74). The slopes showing that the linear relationship between tree size and water content ratio of stem xylem were always steeper than that of other components for the two conifers.ConclusionOur study indicates the similar water related characteristics and their close relations to biomass accumulation and growth in both fast growing species at contrasting climates, illustrating the same coherent strategies of fast growing conifers in water utilization.

Highlights

Plant water storage plays a crucial role in physiological processes and biomass accumulation (Lisar et al, 2012; Hoeber et al, 2014)
The water storage proportion differed among different biomass components (P < 0.001 for both Chinese fir and Korean larch), which varied with age class in Korean larch, especially for leaves and stem xylem
The stem xylem water proportion of Chinese fir increased with age class, while that of Korean larch reached the maximum at medium age, the differences among age classes were not statistically significant in both species

Summary

Introduction

Plant water storage plays a crucial role in physiological processes and biomass accumulation (Lisar et al, 2012; Hoeber et al, 2014). The relationships between water storage and biomass components in two conifer species. The water storage of the stem xylem was always higher in Chinese fir than in Korean larch. The average water content ratio of both conifer species decreased with age, but that of Chinese fir was always higher than that of Korean larch. There was a significant difference in the water storage proportion in the components of Chinese fir (P < 0.001) and Korean larch (P < 0.001). The effects of age class on the water storage of Chinese fir (P = 0.72) and Korean larch (P = 0.077) were not significant. The slopes showing that the linear relationship between tree size and water content ratio of stem xylem were always steeper than that of other components for the two conifers. Conclusion: Our study indicates the similar water related characteristics and their close relations to biomass accumulation and growth in both fast growing species at contrasting climates, illustrating the same coherent strategies of fast growing conifers in water utilization

Methods

Results

Discussion

Conclusion