Karst Plateau Research Articles

Promoting ecological conservation through multi-objective ecological early warning and network regulation in the Karst Plateau, China.

Promoting ecological conservation through multi-objective ecological early warning and network regulation in the Karst Plateau, China.

Community assembly characteristics of abundant and rare bacterial taxa in water, sediment and riparian soil of Wujiang river, China.

Community assembly characteristics of abundant and rare bacterial taxa in water, sediment and riparian soil of Wujiang river, China.

Effects of Different Cooking Methods on Cd Content and Health Risk Assessment of Cabbage Under Cd Stress.

Different cooking and processing methods to some extent influence the content of food elements. Karst plateau mountainous region has a significant geochemical high background of Cd. The study aims to explore the differences in health risks associated with different cooking methods for cabbage and provide a theoretical basis for safe production of cabbage in karst area and the reduction of consumption-related risks. Select three varieties of cabbage [Chi bai er hao (CB), Chun xin huo guo wang (CX), Qing cui chi bai cai (QC)] and use three different cooking methods to cook cabbage according to the cooking habits of local residents (raw, boiled, and fried) on the Cd content of cabbage were studied. The cabbages were grown in soil dosed with known amounts of Cd. Cd content in cabbage significantly increased (P < 0.05) with the increase of exogenous Cd levels. The Cd content of cooked cabbage was significantly lower than that of raw cabbage (P < 0.05). The general rule was raw > stir-fried > boiled. The target hazard quotient (THQ) of cabbage consumption by local residents was found to be QC > CX > CB, and the THQ of different cooking methods was raw > stir-fried > boiled. Residents of the Karst region should choose vegetables that have Cd content below the limit standard and adopt reasonable cooking methods to reduce health risks. Compared to raw, the cooking method of boiling is the most effective, followed by stir-fried. Commonly planted cabbage varieties in karst area; effects of different cooking methods on cadmium content in cabbage; health risk assessment of cabbage cooking methods on different consumer groups.

Phenological Plant Pattern in the Topographic Complex Karstic Landscape of the Northern Dinaric Alps.

Vegetation phenology has lately gained attention in the context of studying human-induced climate change and its effects on terrestrial ecosystems. It is typically studied on various regional and temporal scales. This research focused on the microscale in dolines on the Northernmost part of the Dinaric Alps. The aim was to determine the timing of flowering onset and relate it to topographic and ecological conditions. We studied (1) the floristic gradient along N-W transects divided in 2 m × 2 m plots, from top slopes to the bottom of dolines, and identified discrete groups in relation to this gradient and (2) provided their diagnostic species and communities. The results indicate that the early spring onset of flowering of ground vegetation in the bottom and lower slopes of dolines is stimulated by high spring moisture and nutrient availability, as well as the open canopy of the mesophilous deciduous forests. The flowering onset on the upper slopes and karst plateau starts later, which is due to the precipitation peak in May/June and higher temperatures and light availability of the open canopy of thermophilous deciduous forests. The delayed onset of flowering in late summer in rocky crevices and rocky places is due to a particular physiology stimulated by the harsh site conditions. The phenology pattern along the doline topographic gradient is inverse to general patterns in vegetation phenology. Further study on the role of doline soils should be made to study their impact on phenology.

Potential risk of microplastics in plateau karst lakes: Insights from metagenomic analysis.

Potential risk of microplastics in plateau karst lakes: Insights from metagenomic analysis.

Nature, origin and significance of a clayey cave deposit: Relationship between karst and Oligocene/Miocene tephra (NW Dinarides)

AbstractA limestone cave filled with montmorillonite clay was found in a hill above the karst plateau on the north‐eastern edge of the Adriatic Sea. The cave fill shows no correlation with sediments found in the surrounding caves or other known caves of the Classical Karst, where montmorillonite content is negligible. In other caves, the primary deposited sediments originate from weathered Eocene flysch and were transported into caves by sinking streams. Powder X‐ray diffraction analyses indicate a pure montmorillonite composition with a few coarser quartz grains and heavy minerals. Based on these results and comparisons with tephras from volcanic centres in the wider region, we conclude that the geochemical characteristics of the montmorillonite clay (rare earth element distribution, enriched patterns of light rare earth elements, LaN/YbN ratios and significantly negative Eu/Eu* ratio) are similar to weathered volcanoclastic material of the Smrekovec Volcanic Complex (Oligocene to Miocene eruptions in north‐eastern Slovenia) and transported to the depositional centre by north‐eastern winds. Dating the clay using apatite fission‐track thermochronology yielded 22 ± 7 Ma, while K‐Ar dating gave 23.4 ± 1.7 Ma. Both ages are consistent with the activity of the Smrekovec Volcanic Centre, previously dated to 28–23 Ma. The presence of weathered volcanic ash in the studied cave indicates considerable explosive activity of the stratovolcano, previously interpreted only as a submarine edifice, and confirms the existence of a contemporary karst landscape at the time of volcanic activity where volcanic ash was deposited and subsequently in situ weathered in a levelled corrosion‐tectonic plane. Consequently, it can be concluded that a karst landscape in the north‐western Dinarides has existed since the Late Oligocene, with the studied cave being the only known remnant identified so far. This study presents a rare sedimentary record and highlights the role of karst landscapes as valuable archives of past geological events and environmental changes.

Ecological Health Assessment of Karst Plateau Wetlands Based on Landscape Pattern Analysis

Ecological Health Assessment of Karst Plateau Wetlands Based on Landscape Pattern Analysis

Multiple Environmental Variables as Covariates to Improve the Accuracy of Spatial Prediction Models for SOM on Karst Aera

ABSTRACTAims accurately predicting the spatial distribution of soil organic matter (SOM) is essential for environmental management and carbon storage estimation. However, the diversity of sources of variables poses a challenge in studying the spatial distribution of SOM. Methods in order to address this issue, we propose leveraging multiple environmental variables and employing machine learning models, specifically Lightweight gradient boosting machine learning (LightGBM) and random forest (RF), for predicting SOM spatial distribution. 128 soil samples were collected from the Caohai National Nature Reserve, and their SOM content was measured. Results the study found that the average SOM content was 36.75 g/kg. Compared to traditional linear regression models such as ordinary kriging (OK), ordinary least squares (OLS), and geographically weighted regression (GWR), the machine learning models based on nonlinear regression, LightGBM and RF, demonstrated higher cross‐validated coefficients of determination (R 2) of 0.62 and 0.60, respectively, outperforming the other models. Additionally, RF exhibited lower mean absolute error (MAE) and root mean square error (RMSE), indicating higher stability and generalization capability. The spatial distribution of SOM among the models showed consistency, with higher SOM content observed in southern and near‐Caohai Lake regions and lower SOM content in northern and farther regions from Caohai Lake. Results from the Shapley additive explanations (SHAP) model highlighted agricultural land (AL), pH, and Elevation (ELV) as primary covariates influencing SOM spatial distribution. Conclusions this study provides valuable insights and support for environmental management and carbon storage estimation in the karst plateau region.

ITS amplicon sequencing revealed that rare taxa of tea rhizosphere fungi are closely related to the environment and provide feedback on tea tree diseases.

The rhizospheres of plants and soil microorganisms are intricately interconnected. Tea trees are cultivated extensively on the karst plateau of Guizhou Province, China; however, the understanding of the interactions among fungal communities, community taxa, and diseases impacting tea tree in the soil rhizosphere is limited. Our aim is to offer insights for the advancement of modern agriculture in ecologically fragile karst tea gardens, as well as microbiomics concepts for green and sustainable environmental development. This study utilized the internal transcribed spacer high-throughput sequencing technology to explore the symbiotic relationship between rhizosphere fungi and plant disease feedback in multiple tea estates across the Guizhou Plateau. The ecological preferences and environmental thresholds of fungi were investigated via environmental variables. Furthermore, a correlation was established between different taxa and individual soil functions. Research has indicated that tea leaf blight disrupts symbiotic connections among fungal groups. For various taxa, we found that numerous taxa consistently maintained core positions within the community, whereas rare taxa were able to stabilize due to a high proportion of positive effects. Additionally, abundant taxa presented a wider range of environmental feedback, whereas the rare taxon diversity presented a stronger positive association with the soil Z score. This study contributes to our understanding of the importance of rare taxa in plant rhizosphere soil processes. Emphasis should be placed on the role of rare taxa in pest and disease control within green agriculture while also strengthening systematic development and biogeographical research related to rare taxa in this region.IMPORTANCEIn this study, based on internal transcribed spacer high-throughput sequencing, fungal communities in the rhizosphere soil of tea trees and their interactions with the environment in karst areas were reported, and the symbiotic relationships of different fungal taxa and their feedback to the environment were described in detail by using the knowledge of microbial ecology. On this basis, it was found that tea tree diseases affect the symbiotic relationships of fungal taxa. At the same time, we found that rare taxa have stronger cooperative relationships in response to environmental changes and explored their participation in soil processes based on fungal trait sets. This study will provide basic data for the development of modern agriculture in tea gardens and theoretical basis for the sustainable prevention and control of tea tree diseases.

Physically-based digital geomorphological mapping: Case study of glacial and karst topography

Physically-based digital geomorphological mapping: Case study of glacial and karst topography

Desertification Assessment Using the Modified Mediterranean Desertification and Land Use Model in a Karst Plateau

Desertification is among the most severe environmental problems in many countries at present, and threatens the integrity of natural environments and the sustainability of related natural resources. This work aims to assess proneness to desertification in the Alta Murgia karst plateau (Apulia, Southern Italy) through the integration of the modified Mediterranean Desertification and Land Use model (MEDALUS) with a GIS-based approach. The model includes indexes for climate, vegetation, soil, and management, all combined to assess environmentally sensitive areas (ESAs) regarding desertification. Given the karst features of the study area, the management index was modified and renamed the Karst Management Quality Index (KMQI). This modification was made by incorporating the Karst Disturbance Index (KDI), based on a series of indicators divided into five categories: geomorphology, hydrology, atmosphere, biota, and cultural factors. According to the model, the results indicated that the whole area (97%) is within the Critical type of ESA, with no area being assessed as the “Non-Affected” or “Potential” type. A total of 57% of the study area falls into Critical sub-type 2, 32% falls into sub-type 3, and 8% falls into sub-type 1. The remaining percentage (3%) belong to a non-optimal category, i.e., the Fragile type (sub-type F3) class. The obtained results could be explained, more than by climatic or ecological factors, by a series of anthropogenic activities carried out over the years that strongly modified and disturbed the original karst landscape, with a highly negative impact on the Alta Murgia karst.

Characteristics and driving factors of spatiotemporal changes in soil erosion in the karst plateau mountainous region over 20 years.

Soil erosion is one of the main issues that endangers global ecosystems. This study explored the spatiotemporal distribution of soil erosion and its drivers in the karst plateau mountainous region. A detailed examination of topography, soil, vegetation, land use, and precipitation data from 2000 to 2020 was conducted in Bijie City using the revised universal soil loss equation model. We also explored the driving forces using a geographical detector. The findings show that between 2000 and 2020, soil erosion first decreased, followed by an increase. The southwest, south, and northern regions contained the highest intensity of soil erosion. Land use, slope, and precipitation are the primary factors influencing soil erosion, with slopes having the greatest impact. By improving our understanding of the dynamics of soil erosion and the primary variables that influence it in karst plateau mountainous environments, our findings can assist in the development of strategies and technical support for sustainable soil and water conservation.

Fruit traits of different variants of Zanthoxylum planispinum var. dingtanensis in the karst plateau valley area of Guizhou Province, Southwest China.

Many studies have shown that seed traits, which are among the most important plant traits, can be inherited stably, a finding which is of great value for the improvement of seed germination, seed propagation, seedling establishment, plant breeding, and ecological restoration. The differences in phenotype and nutritional traits and their interactions in Zanthoxylum planispinum var. dingtanensis were ascertained, and the nutrient input rule and the strategy of resource balancing were analyzed in order to provide a scientific basis for the screening of improved variants of the test plant. The nutrient distribution with in the tissues of Z. planispinum var. dingtanensis fruit was that the pericarp had adequate concentrations of N and P concentrations and the seed was also sufficient in P, but low in N concentration. Inorganic nutrients were particularly invested in the pericarp, while organic nutrients are more likely to be stored in the seed. In the economic spectrum of seed traits, the large leaf Zanthoxylum variant represented the low-investment economic type, the tufted leaf Zanthoxylum variant represented the high-investment luxury type, and the safflower Zanthoxylum and acutifoliate leaf Zanthoxylum variants represented transitional types. Inorganic nutrients were more invested in the pericarp to produce secondary metabolites, while organic nutrients are more likely to be stored in the seed to ensure seed germination and seedling establishment in order to achieve inheritance. The variants of Z. planispinum var. dingtanensis differ in terms of resource allocation and balance, which could be further exploited through combining characters in breeding programs.

Health risks of potentially toxic elements in Cyprinus carpio in the karst plateau lake, China.

Elevated potentially toxic elements (PTEs) in aquatic products could threaten the health of ordinary consumers. Levels of chromium (Cr), arsenic (As), lead (Pb), and mercury (Hg) in Cyprinus carpio in karst plateau freshwater Lake, Caohai Lake, China were quantified using inductively coupled plasma mass spectrometry (ICP-MS) and evaluated using a risk method with Monte Carlo simulation. Levelsof Cr, As, Pb, and Hg in muscle tissue were substantially lower than those in viscera. The maximum concentration of muscle-bound Cr, As, Pb, and Hg were less than the standard references set by Chinese Food Codex (GB 2762-2022). The levels of Cr, As, Pb, and Hg in muscle tissue were independent of fish weight and length. The hazard index of all investigated elements in muscle tissue wereless than one for adults and children, whereas the target hazard quotients of muscle-bound PTEs for children were higher than those for adults. Results indicated that exposure duration was the largest contributor to the hazard quotient of Cr, As, and Hg, whereas the concentration of Pb in muscle was the most sensitive factor affecting the variation in hazard quotient of Pb. There is no risk related to the normal intake of muscle-bound Cr, Pb, As and Hg with the consumption of Cyprinus carpio. A better definition of the probability distribution for exposure duration and PTEs concentration could result in a more accurate hazard quotient. © 2024 Society of Chemical Industry.

Human and Natural Activities Effects on Soil Erosion in Karst Plateau Based on QAM Model: A Case Study of Bijie City, Guizhou Province, China

The Karst plateau region has a unique natural erosion environment and sharp human–land conflicts. This study selected Bijie City, Northwest Guizhou, as the study area. To quantitatively analyze the human and natural impacts on soil erosion in this area, this paper evaluated the anthropogenic and natural soil erosion based on the Revised Universal Soil Loss Equation (RUSLE) coupled with the Quantitative Analytical Model (QAM). The results showed the following: (1) the total soil erosion modulus in the study area showed an increasing trend: 37.86 t/(ha·a) in 2010, 42.12 t/(ha·a) in 2015, and 48.67 t/(ha·a) in 2020; (2) human activities reduced soil erosion, with an anthropogenic soil erosion modulus of −13.79 t/(ha·a) in 2015 and −17.36 t/(ha·a) in 2020, indicating that human activities, such as projects of returning farmland to forests and rocky desertification control, played a key role in decreasing soil erosion in the study area.; and (3) the percentage of the area of soil erosion deterioration dominated by natural factors (AGN) is gradually decreasing, 89.47% in 2015 and 81.85% in 2020; the percentage of the area of soil erosion deterioration dominated by human activities (AGH) is increasing from 6.17% in 2015 to 13.80% in 2020; and the percentage of the area of soil erosion mitigation caused by human activities (ALH) and the area of soil erosion not affected by natural and human activities (NNH) showed no significant change. This result suggests more attention should be paid to the area of AGH to control soil erosion. This study analyzed the roles of natural factors as well as human activities in the Karst plateau, enriched the application scope of the QAM, and provided new ideas for theoretical research in this field.

Reluctant Compliance and Collaborative Fiscal Disobedience: How Hmong Consumers Evade Value-Added Tax in Vietnam’s Northern Uplands

For decades, the Vietnamese socialist state has failed to enforce taxation on local Hmong in Đồng Văn, a vast karst plateau in the country’s northern upland region. A recent rise in local tax revenue from Value-Added Tax (VAT) is optimistically perceived by state authorities as a turning point in the fiscal relationship between the state and the evasive population. This article shows that what appears to be a ‘success’ of taxation is the result of both reluctant compliance of local Hmong with a new technique of state control that ties consumer desires to the payment of tax, and their continued pursuit of ‘fiscal disobedience’ using various tactics to evade the novel taxing power of the state. Compared to their previous efforts of tax evasion, evading VAT requires fiscal disobedience of a collaborative kind, involving not only Hmong consumers but also vendors and even agents of the state.

Phosphorus resource partitioning underpins diversity patterns and assembly processes of microbial communities in plateau karst lakes

Phosphorus resource partitioning underpins diversity patterns and assembly processes of microbial communities in plateau karst lakes

Spatial-temporal characterization of cropland abandonment and its driving mechanisms in the Karst Plateau in Eastern Yunnan, China, 2001-2020.

The karst plateau is dominated by mountainous and hilly landforms, with low mechanization level of cropland, high difficulty of cultivation, and obvious phenomenon of cropland abandonment, which threatens regional food security. This study aims to analyze the spatial-temporal variation and its driving mechanisms of abandoned cropland in the Karst Plateau in Eastern Yunnan, China (KPEYC) between 2001 and 2020. To achieve this goal, 18 key factors from population, economic environment, cropland attributes, and farming conditions are selected. Moreover, correlation analysis, geodetector, and regression analysis methods are applied from three perspectives: temporal change, spatial distribution and spatial-temporal change. The results show that: (i) The cropland abandonment rate (CAR) in the KPEYC shows a fluctuating trend, with an average value of 9.78%, and the spatial distribution shows a pattern of "high in the center and low in the south and north". (ii) From the perspective of temporal change, gross value of agricultural production, and gross value of industrial production have the largest correlation coefficients with CAR. (iii) The explanatory power of gross tertiary industrial production, gross value of industrial production, followed by soil thickness. (iv) Gross value of agricultural production, and gross tertiary industrial production are the core driving forces for the spatial-temporal change of CAR. The higher the gross value of agricultural production and gross tertiary industrial production, the lower the CAR. elevation, soil thickness, and traffic mileage are the main driving factors for the spatial-temporal change of CAR. The study indicates that economic factors are decisive for cropland abandonment in the KPEYC. Based on the results, this study can provide decision-making support for local prevention and control of cropland abandonment, and the local community needs to promote land transfer and concentration and local urbanization according to local conditions, improve agricultural policies, improve farming conditions, etc. in order to increase farmers' enthusiasm for production, promote the rational use of cropland, and solidly push forward ecological restoration and management, optimize ecological spatial patterns, manage serious areas of rocky desertification, and appropriately alleviate the contradiction between people and land.

Simulation of a former ice field with Parallel Ice Sheet Model – Snežnik study case

Abstract. In this paper, we present a reconstruction of climate conditions during the Last Glacial Maximum on a karst plateau Snežnik, which lies in Dinaric Mountains (southern Slovenia) and bears evidence of glaciation. The reconstruction merges geomorphological ice limits, classified as either clear or unclear, and a computer modelling approach based on the Parallel Ice Sheet Model (PISM). Based on extensive numerical experiments where we studied the agreements between simulated and geomorphological ice extent, we propose using a combination of a high-resolution precipitation model that accounts for orographic precipitation combined with a simple elevation-based temperature model. The geomorphological ice extent can be simulated with climate to be around 6 °C colder than the modern day and with a lower-than-modern-day amount of precipitation, which matches other state-of-the art climate reconstructions for the era. The results indicate that an orographic precipitation model is essential for the accurate simulation of the study area, with moist southern winds from the nearby Adriatic Sea having a predominant effect on the precipitation patterns. Finally, this study shows that transforming climate conditions towards wetter and warmer or drier and colder does not significantly change the conditions for glacier formation.

Spatial Differentiation Characteristics and Influencing Factors of Surface Soil Cd in Karst Plateau Area of Guiyang City

In order to explore the spatial differentiation characteristics and variation law of soil Cd content in a high geological background area, 14 421 topsoil samples were collected from topsoil in the karst area of Guiyang City. Global Moran's I index, cold hot spot analysis, semi-variance function, and Kriging interpolation were used to reveal the spatial structure and distribution law of soil Cd content. The influence of environmental factors on soil Cd content and its main controlling factors were analyzed through analysis of variance and geographic detector. The results showed that： ① The Cd content of karst surface soil in Guiyang varied from 0.03 to 1.36 mg·kg-1, with an average of 0.440 mg·kg-1, which was 1.77 times and 5.95 times the Guizhou soil Cd background value and Chinese soil Cd background value, respectively. The over-standard rate of soil Cd was 30%, which was 4.29 times that of 7% of soil Cd in China. ② There was a significant spatial positive correlation of soil Cd content, showing an aggregation trend in the global space, whereas in the local region, the northeast and southwest were hot spots, and the north was a cold spot. The nugget coefficient of soil Cd content was 10.37%, indicating that soil Cd was mainly affected by structural factors. ③ In terms of spatial distribution, soil Cd showed different accumulation trends. In some massive soils, such as Xifeng County, Xiuwen County, Qingzhen City, Huaxi District, and Nanming District, the soil ω（Cd）was less than 0.3 mg·kg-1. The soil ω（Cd）was between 0.3 and 0.6 mg·kg-1,and soil Cd in Baiyun District, Wudang District, Guanshan Lake area, and Yunyan area as a whole lied within this range. The soil ω（Cd）between 0.6 and 0.9 mg·kg-1 was concentrated in the southwest of Qingzhen City, the south of Huaxi District, and the north of Kaiyang County, whereas soil ω（Cd） between 0.9 and 1.2 mg·kg-1 was mainly concentrated in the southwest of Qingzhen City. The extreme value of soil Cd content （ &gt; 1.2 mg·kg-1） was mostly distributed in Kaiyang County, Xiuwen County, Qingzhen City, and Huaxi District. ④ The results of analysis of variance and geo-detector showed that different environmental factors had significant effects on the spatial differentiation of soil Cd, but their explanatory power on soil Cd content varied： stratum （0.176 5） &gt; soil type （0.026 0） &gt; organic matter （0.025 1） &gt; altitude （0.010 5） &gt; parent rock （0.007 3） &gt; land use （0.006 4） &gt; pH （0.001 3）, and the interaction between stratum and arbitrary environmental factors was the greatest. Therefore, stratum was the main factor affecting the spatial differentiation of soil Cd content.