Litter eco-hydrological function characteristics of three typical plant communities in the area of Karst peak-cluster depressions from Guizhou, China

Abstract

Litter is an important component of forest ecosystems and plays an important eco-hydrological function. Many studies have been carried out on litter at present, but less research has been carried out on the eco-hydrological service functions of litter in different plant communities in Karst, especially in the area of Karst peak-cluster depressions in southwest China. To reveal the characteristics of the hydrological function of the litter layer of the plant community in the area of Karst peak-cluster depressions around FAST (Five-hundred-meter Aperture Spherical Radio Telescope), three typical plant community litter layers of the broad-leaved forest, coniferous forest, and shrub were selected as research objects, and the hydrological function of the litter layer of different plant community types was studied using the immersion method. The results indicated: 1) The litter layer of the broad-leaved forest plant community has the strongest function of intercepting and regulating precipitation (Mlmax = 24.17±0.33 t/ha, Msv = 19.93±0.21 t/ha), and its hydrological service function is the best. 2) The higher the decomposition degree of litter, the stronger the interception function. 3) The fitted equations for both the litter water-absorption capacity (Qct) and time (t) for plant communities were Qct = b + alnt, and the fitted equations for both the litter water-release capacity (Qst) and time (t) were Qst = a t b. 4) The fitted equations for both the water absorption and release rates (vc and vs) and time (t) of the litter were v = a t -b. The water absorption rates of litter were the fastest within 5 min (15529.01~22634.43 g/kg·h), with the greatest interception and storage function for short-term rainfall.

Tree species composition affects litter eco‐hydrological function in Pinus massoniana conifer‐broadleaf mixed forest stands in southwest China

“…Litter characteristics, climatic factors, forest attributes and terrain factors were the dominant influencing factors (explaining 78% of the variation) on the water storage capacity of the forest ecosystem litter layers (Liu et al, 2023). The degree of litter decomposition is also an important factor affecting LWHC, and the higher the degree of litter decomposition, the higher the LWHC (Anna et al, 2015; Su & Liu, 2022; Zhang et al, 2022; Zhou et al, 2018). In line with previous studies, the LWHC of semi‐decomposed litter was significantly higher than that of undecomposed litter (Figure 3a), which may have resulted from a looser litter structure and an increasing number of voids due to decomposition, thus allowing a greater LWHC (Zhang et al, 2022).…”

“…Litter water‐holding capacity (LWHC) was determined by indoor immersion experiment (Zhang et al, 2022; Zhou et al, 2018). In accordance with the proportion of different needle‐leaf and broad‐leaf litters, 30‐g litters from the undecomposed layer were put into nylon mesh bag (size of 200 mesh) and immersed in a plastic basin with clean water and ensure that all litters were submerged under the water surface.…”

“…Litter was collected from six 50 cm × 50 cm randomly plot, there litter layer was divided into the undecomposed litter layer and the semi‐decomposed litter layer, the total litter samples was 108. The undecomposed litter and semi‐decomposed litter were dried at 80°C to constant weight, and weighted (Zhang et al, 2022). The undecomposed litter layer was divided into needle‐leaf, broad‐leaf, dead branches, bark, fruit and debris, and recorded respectively (Zhu et al, 2021).…”

“…Exactly 30 g of mixed sample obtained from litter samples of semi-decomposition layer was used to determine LWHC. LWHC was calculated by following formula (Sui et al, 2021;Zhang et al, 2022):…”

“…For example, litter yield and nutrient return in mixed stands are better than in pure Cunninghamia lanceolata plantations in southern China (Wang et al, 2007). Therefore, mixed forests generally have greater litter accumulation, a thicker litter layer, higher degree of litter decomposition and higher litter hydrological regulation ability (Hu et al, 2017; Zhang et al, 2022; Zhao et al, 2019).…”