Response of Morphological Characters and Photosynthetic Characteristics of Haloxylon ammodendron to Water and Salt Stress

Guanghui Lv,Fang Yang,Yadong Qie,Hengfang Wang,Dong Hu,Lamei Jiang

doi:10.3390/su13010388

Abstract

In arid desert areas, Haloxylon ammodendron plays an important role in maintaining the ecological balance of desert oases. However, there are few studies on the physiological characteristics of Haloxylon ammodendron under an environmental gradient. Here, we studied the changes in the morphological and photosynthetic characteristics and their correlations in Haloxylon ammodendron in the four habitats of the Ebinur Lake wetland. Our results show that in high-water and high-salt habitats, photosynthesis is affected by “stomata restriction,” while in other habitats, photosynthesis is mainly affected by “non-stomata restriction.” In addition, when the soil conditions were good, Haloxylon ammodendron chose leaf construction featuring high specific leaf area, while when the soil conditions were worse, it chose an opposite leaf construction model to ensure the optimal allocation of carbon assimilation products in heterogeneous habitats. This study will deepen our understanding of the trade-off strategy between the accumulation and distribution of plant photosynthate in special habitats in arid areas. The results are of theoretical value for analysis of the ecological adaptation mechanisms of plants in arid desert areas.

Highlights

In arid and semi-arid areas, water and salt are the main environmental factors limiting plant growth
The measured values of soil water and salt content under the canopy of 62 Haloxylon ammodendron were clustered according to the salinization and drought properties of plant habitats in Ebinur Lake Basin (Table 2)
The results showed that the soil salt content was higher under gradient I (Table 2), but Haloxylon ammodendron plants grew well, and the basal diameter, plant height, and crown area were significantly higher than in gradients II, III, and IV (Table 3) indicating that Haloxylon ammodendron could cope with salt stress

Summary

Introduction

In arid and semi-arid areas, water and salt are the main environmental factors limiting plant growth. The morphological structure and photosynthetic characteristics of plants will change according to the soil water and salt contents. Once the soil water content decreases, the plant will develop a more simple, low-lying structure. Drought stress causes leaf stomata to close and mesophyll cells to become damaged; photosynthetic enzyme activity is decreased, the chloroplast structure may be destroyed, chlorophyll content may be decreased, and the photosynthetic rate of plants will be decreased [1,2]. Salt stress affects the components, permeability, transport, and ion flow of the plant plasma membrane, leading to damage to the normal functioning of the cell membrane

Methods

Results

Discussion

Conclusion