Differential Water Conservation Capacity in Broadleaved and Mixed Forest Restoration in Latosol Soil-Eroded Region, Hainan Province, China

Suyi Chen; Yanping Huang; Mei Yan; Yujie Han; Kang Wang; Zexian Chen; Dongshuo Ruan; Yan Yu; Zhihua Tu

doi:10.3390/plants13050694

Differential Water Conservation Capacity in Broadleaved and Mixed Forest Restoration in Latosol Soil-Eroded Region, Hainan Province, China

Plants (Basel). 2024 Feb 29;13(5):694. doi: 10.3390/plants13050694.

Authors

Suyi Chen¹, Yanping Huang¹, Mei Yan¹, Yujie Han¹, Kang Wang¹, Zexian Chen¹, Dongshuo Ruan¹, Yan Yu¹, Zhihua Tu^{1

2}

Affiliations

¹ School of Tropical Agriculture and Forestry, Hainan University, Haikou 570228, China.
² Engineering Research Center of Rare and Precious Tree Species in Hainan Province, Haikou 570228, China.

Abstract

The water conservation capacity of the litter and soil layers of forest ecosystems improves the function of forest ecosystems in conserving soil and water. Plantation restoration plays a key role in preventing soil erosion. In order to evaluate the water conservation capacity of plantation restoration in Latosol soil-eroded region, we analyzed the litter thickness and mass, water absorption process, water holding recovery process, and soil water holding capacity of five restoration types (Hevea brasiliensis, Acacia mangium, Eucalyptus robusta, Acacia-Eucalyptus, and Acacia-Hevea) in the Mahuangling Watershed, Hainan province. The results showed that the thickness of the litter ranged from approximately 3.42 ± 0.24 to 4.73 ± 0.81 cm, and the litter mass ranged from 5.04 ± 1.52 t·ha^-1 to 13.16 ± 1.76 t·ha^-1, with higher litter mass in the SL layer than in the UL layer. The litter mass of A. mangium was higher than that of H. brasiliensis, E. robusta, Acacia-Eucalyptus, and Acacia-Hevea, which was 3.16 ± 1.76 t·ha^-1. A. mangium forest was significantly higher than other plantation restoration types in terms of the maximum water retention capacity (Q_max) and the effective water retention capacity (Q_eff). The soil bulk weight ranged from approximately 1.52 ± 0.09 to 1.59 ± 0.08 g·cm^-3, and porosity ranged from 31.77 ± 4.72 to 35.62 ± 3.02%, both of which increased with the depth of the soil layer. The water holding capacity of 0-60 cm soil varied from approximately 12.94 ± 7.91 to 45.02 ± 31.79 t·ha^-1, with A. mangium having the best soil permeability and the strongest soil water holding capacity. The entropy weight method was used to conduct a comprehensive evaluation, and the results showed that the water conservation capacity of the soil layer was 1.26 times higher than that of the litter layer, in which the water conservation capacity of A. mangium was the strongest, with a comprehensive evaluation value of 0.2854, which effectively intercepted rainfall and reduced surface runoff. Hence, we suggest that the planting of A. mangium should be considered in future ecological restoration projects of the erosion area of Mahuangling in order to improve the function of conserving soil and water in a restoration forest ecosystem.

Keywords: Latosol soil-eroded region; forest restoration; litter layer; soil layer; water conservation capacity.

Grants and funding

This research was funded by National Natural Science Foundation of China, grant number 42267048; the Hainan Provincial Natural Science Foundation of China, grant numbers 420RC532 and 319QN159; the Scientific Research Fund of Hainan University, grant number KYQD(ZR)1950; and the Fund of Department of Water Resources of Hainan Province, grant numbers HD-KYH-2023371, HD-KYH-2023201, HD-KYH-2022350, and HD-KYH-2022238.