The growth and overlay of a large number of bryophytes in the broken soil patches between the exposed bedrocks of karst have an essential influence on the infiltration and runoff process between the exposed bedrocks and even the whole rocky desertification area. The purpose of this study is to explore the effects of moss on the infiltration and runoff of soil patches between karst exposed bedrocks and the processes of rainfall, runoff and infiltration transformation on slopes through rainfall experiments. The results showed that the slopes between the karst outcrops are dominated by subsurface and underground pore runoff. More than 50% of precipitation is lost through underground pores, with surface runoff accounting for only 1–17% of the total. Bryophyte overlay significantly reduced the initial runoff from subsurface and underground pore runoff, and advanced the steady-state time of runoff from subsurface and underground pore runoff, suggesting that bryophyte coverage may reduce the risk of soil erosion caused by short-duration rainfall. Eurohypnum has a significant inhibitory effect on percolation between exposed bedrock and reduces rainfall leakage from subsurface and underground pores. Thuidium has a strong intercepting effect on rainfall, significantly reducing the formation of surface runoff and the risk of surface soil erosion. Moss overlay has an essential role in soil and water conservation between karst exposed bedrock, and Eurohypnum and Thuidium can be considered as pioneer mosses for ecological restoration in the process of rocky desertification control and ecological restoration, which can effectively solve the serious problem of soil and water loss in karst rocky desertification area and improve the benefit of soil and water conservation in karst area.
Aims Underground fissure soil is an important soil resource in karst rocky desertification area, but there are few reports on its physical and chemical properties and soil ecological stoichiometry. This study aims at investigating the physicochemical properties, nutrient content and stoichiometric characteristics of subsurface fissured soils in karst areas, which will help to understand their intrinsic linkage mechanisms and provide a scientific basis for making full use of fissured soils.Methods Typical karst fissures were selected through a combination of field investigation and in-laboratory analysis, and soil physicochemical properties were determined through field sampling and indoor tests. Results We found that as the depth of the fissure soil layer increases, the silt content and clay content increase and the sand content and soil water content continue to decrease. The fissure soil is basically weakly alkaline. The TN content does not change much from the surface to the lower part of the fissure, and the AN, TP and AP contents in the fissure generally decrease. In general, SOC, nitrogen and phosphorus are mainly concentrated in the surface soil compared to the other soil layers in the fissure; the C/N, N/P and C/P ratios are higher in the upper part of the fissure; C/P and N/P are higher and C/ N is lower in SL, while the opposite is true in AL. Conclusions The low nutrient content and high ecological stoichiometry of karst rift soils suggest that rift soils in karst areas need more soil nutrient management, and improvement of quality status.
<p>Rocky desertification has become one of the global ecological environmental problems. Karst rocky desertification area of southwest China is suffering from ecosystem degradation, and the combination of water and soil resources determines the stability of their ecosystems. In recent years, soil leakage has attracted attention because it was that under the development of carbonate shallow fissures, the water and soil along the such pipes as shallow fissures leaks underground, resulting in the allocation of soil and water underground, affecting the integrity of the overlying ecosystem. This study aimed to reveal the leakage loss process, characteristic and mechanism of soil in fissures on sloping lands in the karst area, taking fissures on sloping lands in karst plateau of Guizhou province as the research object, combined with the methods of paint marking and soil particle analysis was conducted to study the leakage loss process of soils in fissures. The result showed that rainstorm or downpour is the key factor of soil fissure leakage loss, and its leakage form is mainly soil creep. Soil creep displacements of different fissure at 104.5 mm rainfall event between 1.0 cm and 2.5 cm, accounting for more than 62.5% of the displacement at 332.7 mm rainfall event, while the soil creep displacement of fissures just range from 0.2 cm to 0.3 cm at the larger rainfall of 181.5; the particle content with different particle sizes in rock-soil interfaces and soils of six fissures selected under 3 precipitation events (104.5, 151.2 and 332.7 mm) showed that the fissure soil does not leak down uniformly, but some particles at the soil layers or rock-soil interfaces leak to the lower layer at random in the process of creep leakage loss. In other words, the occurrence of soil layers and particles are accidental, and the soil particles in the rock-soil interfaces and the soil layers of fissures have the possibility to leak down. Facts proved that the soil creep leakage loss in fissures is a complex process which is determined by the internal factors such as fissure structure, fillings characteristics and bottom connectivity, and such external factors as rainfall etc.<br>Key words: underground leakage loss; soil; karst fissure; sloping land; karst plateau</p>
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.