Succession of plant community composition and leaf functional traits in responding to karst rocky desertification in the Wushan County in Chongqing, China

Abstract

Karst rocky desertification (KRD) is a process of soil desertification, which leads to the decline of soil quality and biomass. We conducted a plant community survey in KRD areas in Chongqing, China. Our aims were to determine key soil properties that shape plant communities and to identify essential leaf functional traits (LFTs) in responding to the progression of KRD. The vegetation survey was carried in a total of twenty study sites (five replicates for four stages of KRD) in the Wushan County in Chongqing, China. Leaves were collected from all the species in every site and measured/calculated for five LFTs, namely, specific leaf area, leaf area, leaf thickness, leaf tissue density, and leaf dry matter content. Soil samples were collected in triplicates in each site to measure soil properties. We found that the overall richness and diversity of community decreased along with the progression of KRD. Phanerophytes predominated in all the KRD areas. Soil pH was the main determinant of vegetation structure. Leaves with lower area yet higher density had the optimal adaptability in KRD regions, which can be planted as pioneer vegetation to restore land in KRD regions.

Soil pH Is the Primary Factor Correlating With Soil Microbiome in Karst Rocky Desertification Regions in the Wushan County, Chongqing, China

“…Detailed descriptions of study area are reported in a previous study (Qi et al, 2017 ). Briefly, the study area is located in the Wushan County, northeast Chongqing (N 30°46′-31°28′, E 109°33′-110°11′).…”

“…The land in the Wushan County (northeast Chongqing) is highly susceptible to desertification. Roughly 70% of soils (2066 km 2 ) in the Wushan County are M- and S-KRD areas (Qi et al, 2017 ).…”

“…Many studies report causes of KRD and changes in soil and vegetation community in response to KRD progression (Calò and Parise, 2006 ; Xie et al, 2015 ; Zhang et al, 2016 ; Qi et al, 2017 ). It is suggested that besides the natural susceptibility to desertification in the karst region, anthropogenic disturbances and soil exploitation are the other main reasons accelerating soil desertification (Yan and Cai, 2015 ).…”

“…Furthermore, soil pH significantly increases along the KRD gradient, and is associated with decreased soil quality (Wang et al, 2004 ). As the result, vegetation diversity and coverage significantly decreases in accordance to desertification progression (Zeng et al, 2007 ; Qi et al, 2017 ). Many studies focus on determining correlations of aboveground factors with KRD progression.…”

Soil pH is the primary factor driving the distribution and function of microorganisms in farmland soils in northeastern China

“…Some of each composite soil sample were stored at − 80°C to extract total soil DNA for high-throughput sequencing, and the rest of each samples was gently air-dried and used for physicochemical measurements. Physicochemical parameters, e.g., pH, soil organic C (SOC), and available N, P, and K were measured for each composite sample according to the methods of previous studies (Sun et al 2015;Qi et al 2017).…”