Effects of Close-to-Nature Transformation on Soil Enzyme Activities and Organic Carbon Fractions in Cuninghamia lanceolata and Pinus massoniana Plantations

Abstract

Soil enzymes are involved in the process of mineralization of soil organic matters. The close-to-nature transformation (CNT) of plantations changes the soil enzyme activities by changing the composition of stand vegetation, which in turn affects the change process of soil organic carbon. We therefore selected two typical coniferous plantations in southwest China, Pinus massoniana and Cunninghamia lanceolate, to explore the effects of CNT on soil enzyme activities and soil organic carbon, and the relationship between them is explored through comparative study. Compared with control stands (CCK and PCK), CNT enhanced soil organic carbon; the content of water-soluble organic carbon in the 0–10 cm soil layer of the transformed C. lanceolata plantations (CCN) is 81.29% higher than those in the control stands (p < 0.05); the contents of particulate organic carbon and water-soluble organic carbon in the 10–30 cm soil layer are 95.42% and 48.68% higher than those in the control stands (p < 0.05), respectively; after the CNT, the protease, urease, and acid phosphatase in C. lanceolata plantations were higher than control stands, while protease and catalase in P. massoniana plantations were higher than control stands. Correlation analysis showed that catalase and protease were more closely related to organic carbon components than other organic enzymes; redundancy analysis (RDA) results show that pH and total nitrogen are key factors that cause changes in carbon fractions after the CNT. In general, CNT enhanced soil organic carbon in coniferous plantations, which was more conducive to soil organic carbon accumulation but had a negative effect on soil organic carbon stability to a certain extent. Therefore, the effect of tree species configuration on soil carbon stability components should be considered in the forest management practice.

Influence of Eucalyptus Plantation on Soil Organic Carbon and Its Fractions in Severely Degraded Soil in Leizhou Peninsula, China

“…The C/N ratio of shrub leaf litter is low [55,56], thus, the C/N ratio of soil was correspondingly low. Soil with a lower C/N ratio had a higher organic matter decomposition rate [12,57], and therefore, the decomposition of leaf litter was faster. In addition, the synergistic non-additive effects of litter mixing [58,59] produced after various litter types were mixed could accelerate litter decomposition.…”

“…SOC content is determined by the long-term balance between organic carbon input from litterfall, roots, and organic carbon loss by processes such as decomposition, leaching, and dissolved carbon export [8,9]. It is difficult to respond to short-term ecosystem disturbances and can't well reflect short-term changes in soil quality and organic carbon conversion rate [2,[10][11][12]. Soil labile organic carbon (LOC) accounts for only a small part of the total organic carbon pool, but it is more sensitive to ecosystem disturbances than Forests 2022, 13, 1606 2 of 15 soil organic carbon (SOC) [13,14].…”

Factors influencing the assembly of understory woody communities in Pinus massoniana plantations in Guangxi, China

“…Plantation forests are an important resources within the global supply of vegetation, not only because they supply timber and timber-derived products, but also because they have secondary environmental bene ts, such as sequestering carbon, increasing soil health, and providing habitat for wildlife (Shu et al, 2022;Ali et al, 2022). In China's forestry industry, which produces 20% of the world's timber supply, Guangxi produces 40% of timber, and Pinus massoniana is one of the three major species comprising their timber forests.…”

Enzymatic Activities of Bok Choy (Brassica rapa subsp. Chinensis) Grown Soil with the Amendment of Sandwich Compost

“…Hence, the studied soil is considered low in pollutants if the range lies between 0.23-0.36 mL and 0.1 mol L −1 KMnO 4 g −1 [5]; Tang et al [6]. Besides, catalase had a signi cant correlation to organic carbon and reduced soil depth [5,7]. Catalase activity in subsoil (50-60 cm) has lowered by 21-43% than surface layer soil.…”