Tracer vertical movement and its affecting factors in karst soil profiles using the simulated leaching method

2021 ◽  
Author(s):  
Jianghu He ◽  
Keli Zhang ◽  
Zihao Cao ◽  
Qihua Ke

<p>Soil erosion is a severe issue in Southwest China due to complex karst geomorphology and excessive farming activities. It is also difficult to observe and evaluate using traditional research methods. Fortunately, as a supplement to traditional methods, the <sup>137</sup>Cs tracing technique has strong potential to monitor and evaluate soil loss in karst regions. However, <sup>137</sup>Cs might move downward with tiny particles under adequate rainfall conditions. This is critical because it directly affects accuracy of using the <sup>137</sup>Cs conversion model to evaluate soil erosion. Thus, in our study, in order to explore whether tracers actually moved vertically and to evaluate the movement distance and the factors influencing the movement, magnetic powder (Fe<sub>3</sub>O<sub>4</sub>) and rare earth oxides (CeO<sub>2 </sub>and La<sub>2</sub>O<sub>3</sub>) were used as the substitute tracers under different conditions (rainfall and leaching area) of a simulated leaching experiment, which possess similar properties as <sup>137</sup>Cs and have no toxicity problems in humans and the environment. The results showed that tracers moved downward 6 cm when water was added to simulate 1-10-year rainfall conditions and 8 cm when water was added to simulate 15-20-year rainfall conditions. The movement distance of tracers increased slowly with increasing water input, and the concentration of the tracers that moved related indirectly to the leaching area. Tracer movement at the edge of the simulated profile was affected by tracer type and concentration since there was no transition layer between soil and plastic column. Our field observations in two karst watersheds showed that ignoring the vertical movement of tracer can cause the overestimation of soil loss amount by 6.90% and 22.22% respectively. This study proved that in the karst area of Southwest China with abundant rainfall, <sup>137</sup>Cs would move vertically, and the soil loss will be overestimated if the vertical movement distance of the tracer is ignored.</p>

2020 ◽  
Author(s):  
Siwen Feng ◽  
Hongya Wang ◽  
Hongyan Liu ◽  
Chenyi Zhu ◽  
Shuai Li

<div>With the implementation of the Grain to Green Project, the vegetation growth in karst region in southwest China has increased. In order to explore whether the growth of trees can be sustained after artificial afforestation in karst area and the influence of the forestland change on soil erosion, the WaTEM/SEDEM model was used to simulate the 11 stages of annual soil erosion in the past 33 years in Chongan river drainage basin in Guizhou, and the dominant influencing factors of soil erosion change in the past 33 years were discussed based the pixel scale in this study. The results showed that the forestland increased in a fluctuating way after the conversion project, and the decrease of forestland was mainly caused by drought, especially in the area where the dolomites were distributed. Therefore, the change of forestland caused no significant improvement in soil erosion since the Grain to Green Project.</div><p><!--5f39ae17-8c62-4a45-bc43-b32064c9388a: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></p>


Author(s):  
Yue Cao ◽  
Shijie Wang ◽  
Xiaoyong Bai ◽  
Huiwen Li ◽  
Cheng Zeng ◽  
...  

Abstract. The prediction of soil erosion is critical to regional ecological assessment and sustainable development. However, due to the geological background of the karst area, the soil holding capacity is very limited, so it is necessary to consider the allowable loss of soil. Here we took thermodynamic dissolution model of carbonate rocks and the lithological characteristics to estimate soil loss tolerance, and corrected and quantitatively evaluated the soil erosion. Major findings are as follows: (1) The soil loss tolerance of homogenous carbonate rocks is 31.10 t · ha · yr−1, carbonate rock intercalated with clastic rocks is 120.81 t · ha · yr−1, carbonate/clastic rock alternations is 282.55 t · h · yr−1, and clastic rock is 500 t · ha · yr−1. (2) After the correction of the soil loss tolerance, the average annual amount of soil loss in the study area is 3.08 t · ha · yr−1, which is 41.12 % of the model. The predicted value of soil erosion is nearly the same as the observed value after modification. (3) It is necessary to reconsider the risk assessment model of soil erosion applicable to karst areas. This paper proposes an idea to estimate soil erosion based on the allowable loss of soil, which is more scientifically and accurately to reflect the soil erosion status of the study area compared with the traditional way. This study provides a corresponding reference for the formulation of soil and water conservation policies in China and the world's karst regions.


2017 ◽  
Author(s):  
Cheng Zeng ◽  
Shijie Wang ◽  
Xiaoyong Bai ◽  
Yangbing Li ◽  
Yichao Tian ◽  
...  

Abstract. In spite of previous studies on soil erosion in Karst landform, limited data are available regarding the spatial and temporal evolution and the correlation of spatial elements of soil erosion in Karst. The lack of this study leads to misassessment of environmental effects on the region especially in the mountainous area of Wuling in China. Soil erosion and rocky desertification in this area influence the survival and development of 0.22 billion people. For this reason, the typical Karst area in South China is the object of this study. This paper aims to analyze the spatial and temporal evolution characteristics of soil erosion and investigate the relationship between soil erosion and rocky desertification by using GIS technology and modified universal soil loss equation (RUSLE) model to reveal the relationship between soil erosion and major natural elements in this area. (1) In 2000–2013, the proportion of the area of micro- and slight erosion increases, whereas the proportion of the area of moderate erosion and above decreases. Erosion of moderate and above levels changes into micro- and slight erosion. (2) The soil erosion area in slope zones at 15°–35° accounts for 60.59 % of the total erosion area and 40.44 % of total erosion. (3) The amplitude reduction in the annual erosion rate is higher in the Karst area than that in the non-Karst area. Soil erosion in different outcrop areas of rock generally shows an improving trend, but the dynamic changes in soil erosion significantly differ among various lithological distribution belts. (4) The soil erosion rate of rocky desertification area with moderate and below levels of erosion decreases, whereas the erosion rate of rocky desertification area with severe erosion level increases. Results show the gradual decrease in the temporal and spatial variation of soil erosion in the study area. Lithology is the geological basis of soil erosion. Changes in the spatial distribution of lithology and rocky desertification induce high soil loss. The area is characterized by high rocky desertification, low erosion module, and decreasing annual erosion rate.


Forests ◽  
2020 ◽  
Vol 11 (8) ◽  
pp. 797 ◽  
Author(s):  
Yuguo Liu ◽  
Changcheng Liu ◽  
Matteo Rubinato ◽  
Ke Guo ◽  
Jinxing Zhou ◽  
...  

The distribution of karst landscapes over the Earth’s surface, to a large extent, follows the distribution of carbonate (limestone and dolomite) and gypsum rocks and together these make up about 12% of the Earth’s land area, and the largest karst region in to world is in Southwestern China. Characterized by a unique set of landforms, these geographical areas also differ from other geomorphic regions by the presence of cave systems in the subsurface. Unfortunately, due to human disturbances, such as deforestation, agricultural expansion, livestock overgrazing and fire, these regions have been affected by varying degrees of degradation, which could also be worsened if water and soil erosion phenomena typical of these areas are considered. Therefore, there is a need to implement measures and strategies to protect these karst areas and develop plans to restore vegetation in this region. To support local and national authorities to achieve this goal, this study aims to characterize nutrient deficiencies in degraded areas and estimate what could be the thresholds required to facilitate the restoration of vegetation in karst areas in southwest China. The results obtained confirm that the total element concentrations for Soil Organic Carbon (SOC), N, K, Ca, P, S and Mg were relatively high in the study karst area in southwest China. However, the total amounts of soil nutrients stored were very low due to the limited amount of soil identified as a consequence of previous deforestation processes undertaken within this study area and this aspect needs to be taken into consideration if aiming at a positive success of future restoration processes.


Author(s):  
Nguyễn Quang Việt ◽  
Trương Đình Trọng ◽  
Hồ Thị Nga

Vinh Linh, the northern district of Quang Tri province is characterized by a diversified topography with a large variety of elevations, high rainfall, and decreasing land cover due to forest exploiting for cultivation land. Thus, there is a high risk of erosion, soil fertility washout. With the support of GIS technology, the authors used the rMMF model to measure soil erosion. The input data of model including 15 coefficients related to topography, soil properties, climate and land cover. The simulations of rMMF include estimates of rainfall energy, runoff, soil particle detachment by raindrop, soil particle detachment by runoff, sediment transport capacity of runoff and soil loss. The result showed that amount of soil loss in year is estimated to vary between 0 kg/m2 minimum and 149 kg/m2 maximum and is divided into 4-classes of erosion. Light class almost covers the region researched (75.9% of total area), while moderate class occupies 8.1% of total area, strong classes only hold small area (16% of total area). Therefore, protection of the forest floor in sloping areas is one of the most effective methods to reduce soil erosion.


2014 ◽  
Vol 18 (9) ◽  
pp. 3763-3775 ◽  
Author(s):  
K. Meusburger ◽  
G. Leitinger ◽  
L. Mabit ◽  
M. H. Mueller ◽  
A. Walter ◽  
...  

Abstract. Snow processes might be one important driver of soil erosion in Alpine grasslands and thus the unknown variable when erosion modelling is attempted. The aim of this study is to assess the importance of snow gliding as a soil erosion agent for four different land use/land cover types in a subalpine area in Switzerland. We used three different approaches to estimate soil erosion rates: sediment yield measurements in snow glide depositions, the fallout radionuclide 137Cs and modelling with the Revised Universal Soil Loss Equation (RUSLE). RUSLE permits the evaluation of soil loss by water erosion, the 137Cs method integrates soil loss due to all erosion agents involved, and the measurement of snow glide deposition sediment yield can be directly related to snow-glide-induced erosion. Further, cumulative snow glide distance was measured for the sites in the winter of 2009/2010 and modelled for the surrounding area and long-term average winter precipitation (1959–2010) with the spatial snow glide model (SSGM). Measured snow glide distance confirmed the presence of snow gliding and ranged from 2 to 189 cm, with lower values on the north-facing slopes. We observed a reduction of snow glide distance with increasing surface roughness of the vegetation, which is an important information with respect to conservation planning and expected and ongoing land use changes in the Alps. Snow glide erosion estimated from the snow glide depositions was highly variable with values ranging from 0.03 to 22.9 t ha−1 yr−1 in the winter of 2012/2013. For sites affected by snow glide deposition, a mean erosion rate of 8.4 t ha−1 yr−1 was found. The difference in long-term erosion rates determined with RUSLE and 137Cs confirms the constant influence of snow-glide-induced erosion, since a large difference (lower proportion of water erosion compared to total net erosion) was observed for sites with high snow glide rates and vice versa. Moreover, the difference between RUSLE and 137Cs erosion rates was related to the measured snow glide distance (R2 = 0.64; p < 0.005) and to the snow deposition sediment yields (R2 = 0.39; p = 0.13). The SSGM reproduced the relative difference of the measured snow glide values under different land uses and land cover types. The resulting map highlighted the relevance of snow gliding for large parts of the investigated area. Based on these results, we conclude that snow gliding appears to be a crucial and non-negligible process impacting soil erosion patterns and magnitude in subalpine areas with similar topographic and climatic conditions.


2020 ◽  
Vol 13 (1) ◽  
pp. 51
Author(s):  
Alexandra Pagáč Mokrá ◽  
Jakub Pagáč ◽  
Zlatica Muchová ◽  
František Petrovič

Water erosion is a phenomenon that significantly damages agricultural land. The current land fragmentation in Slovakia and the complete ambiguity of who owns it leads to a lack of responsibility to care for the land in its current condition, which could affect its sustainability in the future. The reason so much soil has eroded is obvious when looking at current land management, with large fields, a lack of windbreaks between them, and no barriers to prevent soil runoff. Land consolidation might be the solution. This paper seeks to evaluate redistributed land and, based on modeling by the Universal Soil Loss Equation (USLE) method, to assess the degree of soil erosion risk. Ownership data provided information on how many owners and what amount of area to consider, while taking into account new conditions regarding water erosion. The results indicate that 2488 plots of 1607 owners which represent 12% of the model area are still endangered by water erosion, even after the completion of the land consolidation project. The results also presented a way of evaluating the territory and aims to trigger a discussion regarding an unambiguous definition of responsibility in the relationship between owner and user.


Land ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 650
Author(s):  
Wakjira Takala Dibaba ◽  
Tamene Adugna Demissie ◽  
Konrad Miegel

Excessive soil loss and sediment yield in the highlands of Ethiopia are the primary factors that accelerate the decline of land productivity, water resources, operation and function of existing water infrastructure, as well as soil and water management practices. This study was conducted at Finchaa catchment in the Upper Blue Nile basin of Ethiopia to estimate the rate of soil erosion and sediment loss and prioritize the most sensitive sub-watersheds using the Soil and Water Assessment Tool (SWAT) model. The SWAT model was calibrated and validated using the observed streamflow and sediment data. The average annual sediment yield (SY) in Finchaa catchment for the period 1990–2015 was 36.47 ton ha−1 yr−1 with the annual yield varying from negligible to about 107.2 ton ha−1 yr−1. Five sub-basins which account for about 24.83% of the area were predicted to suffer severely from soil erosion risks, with SY in excess of 50 ton ha−1 yr−1. Only 15.05% of the area within the tolerable rate of loss (below 11 ton ha−1yr−1) was considered as the least prioritized areas for maintenance of crop production. Despite the reasonable reduction of sediment yields by the management scenarios, the reduction by contour farming, slope terracing, zero free grazing and reforestation were still above the tolerable soil loss. Vegetative contour strips and soil bund were significant in reducing SY below the tolerable soil loss, which is equivalent to 63.9% and 64.8% reduction, respectively. In general, effective and sustainable soil erosion management requires not only prioritizations of the erosion hotspots but also prioritizations of the most effective management practices. We believe that the results provided new and updated insights that enable a proactive approach to preserve the soil and reduce land degradation risks that could allow resource regeneration.


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