Vulnerability mapping of karst springs and its application for the delineation of protection zones (Mecsek Karst, Hungary)

Over the past decade or two, vulnerability mapping become a useful tool to determine the sensitivity of karst aquifers and allows the analysis of karstic aquifers affected by human activities. The Tettye Catchment, one of the eight catchments of the Mecsek Karst aquifer (SW Hungary), supplies drinking water for Pécs, the fifth most populous city in Hungary. However, due to its partly urbanized character and heterogeneous karstic features, this catchment is highly sensitive to anthropogenic impacts. In this study we aimed to generate resource vulnerability maps and risk maps to assess the role of physical and anthropogenic factors on groundwater vulnerability in the Mecsek Karst. Two formerly validated methods were used, the COP (Concentration, Overlaying layers and Precipitation) and SA (Slovene Approach) methods. The resource vulnerability maps, validated by former tracer tests, were combined with the hazard map obtained from the COST action 620 and EU Water Directive to generate risk maps. Tracer-based transit times were commonly less than 20 days in the majority of the areas of extreme vulnerability. During the current study, a new protocol has been elaborated for the delineation of the protection zones of karstic aquifers. Comparing the two methods, the SA performed better in terms of intrinsic vulnerability mapping, as it had a higher spatial resolution and was more detailed than the COP map and had a more sophisticated vulnerability indexing. In addition, high spatial correlation was revealed between the transit time maps and the SA map. Reassessed risk zonation, with appropriate legal consequences, likely minimizes undesired human activities within the zone of protection, hence maintaining water quality that complies with the protection acts

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Fuzzy or Non-Fuzzy? A Comparison between Fuzzy Logic-Based Vulnerability Mapping and DRASTIC Approach Using a Numerical Model. A Case Study from Qatar

Water ◽

10.3390/w13091288 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1288

Author(s):

Husam Musa Baalousha ◽

Bassam Tawabini ◽

Thomas D. Seers

Keyword(s):

Fuzzy Logic ◽

Numerical Model ◽

Vulnerability Assessment ◽

Anthropogenic Impacts ◽

Groundwater Vulnerability ◽

Vulnerability Mapping ◽

Anthropogenic Contamination ◽

Weighted Overlay ◽

Vulnerability Maps

Vulnerability maps are useful for groundwater protection, water resources development, and land use management. The literature contains various approaches for intrinsic vulnerability assessment, and they mainly depend on hydrogeological settings and anthropogenic impacts. Most methods assign certain ratings and weights to each contributing factor to groundwater vulnerability. Fuzzy logic (FL) is an alternative artificial intelligence tool for overlay analysis, where spatial properties are fuzzified. Unlike the specific rating used in the weighted overlay-based vulnerability mapping methods, FL allows more flexibility through assigning a degree of contribution without specific boundaries for various classes. This study compares the results of DRASTIC vulnerability approach with the FL approach, applying both on Qatar aquifers. The comparison was checked and validated against a numerical model developed for the same study area, and the actual anthropogenic contamination load. Results show some similarities and differences between both approaches. While the coastal areas fall in the same category of high vulnerability in both cases, the FL approach shows greater variability than the DRASTIC approach and better matches with model results and contamination load. FL is probably better suited for vulnerability assessment than the weighted overlay methods.

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Review: Advances in the methodology and application of tracing in karst aquifers

Hydrogeology Journal ◽

10.1007/s10040-020-02278-9 ◽

2021 ◽

Vol 29 (1) ◽

pp. 67-88

Author(s):

Ralf Benischke

Keyword(s):

Fluorescent Dyes ◽

Anthropogenic Impacts ◽

Karst Aquifer ◽

Tracer Tests ◽

Analytical Techniques ◽

Transport Processes ◽

Karst Hydrogeology ◽

Flow Paths ◽

Tracer Methods ◽

Underground Flow

AbstractTracer methods have been widely used in many fields of environmental and natural sciences, and also in human health sciences. In particular, tracers are used in the study of karst hydrogeology, typically focusing on phenomena such as sinkholes, sinking rivers and large karst springs. It is known that tracers have been used since antiquity. The aim of tracer tests has been to investigate underground flow paths, transport processes and water–rock interactions, and to get an insight into the functioning of a karst aquifer. In karst hydrogeology, tracer methods are the most important investigation tools beside conventional hydrological methods. In early times, tracer methods were applied only to investigate underground flow-paths. Later they were also used to elucidate transport processes associated with water flow, and today they are often the basis, together with detailed hydrological information, of groundwater protection investigations and aquifer modelling. Many substances (spores, microspheres, bacteriophages, salt tracers, fluorescent dyes, radioactive substances) have been investigated for their properties and potential usage in environmental investigations, in particular the often unknown and inaccessible underground systems of karst areas. A great number of analytical techniques is available. This includes instrumentation for laboratory applications and direct online, on-site or in-situ field measurements. Modern instruments have a high capability for data acquisition, storage and transmission in short intervals, as a basis for quantitative evaluation and modelling. This enables research on the hydrological and hydrochemical dynamics of aquifers and their response to different natural or anthropogenic impacts.

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APPLICATION OF TRECER METHODS AND HYDROCHEMICAL ANALYSIS ON THE KARST SYSTEM OF Ν . OSSA MOUNTAIN/NE -THESSALY

Bulletin of the Geological Society of Greece ◽

10.12681/bgsg.16706 ◽

2004 ◽

Vol 36 (4) ◽

pp. 2067

Author(s):

Γ. Σταμάτης ◽

E. Ζαγγανά

Keyword(s):

Groundwater Flow ◽

Anthropogenic Impacts ◽

Karst Aquifer ◽

Tracer Tests ◽

Organic Contamination ◽

Surface Loading ◽

The North ◽

North Part ◽

Tracer Methods ◽

Inorganic Chemical

In this paper the hydrogeological conditions of the north part of Ossa mountain are described. The research is focused on the karstic aquifer and the springs of its organic contamination are checked. Hydrochemical methods and tracer methods with NaCI and Uranine as tracers were applied. Regarding the inorganic chemical load, karstic waters show high quality status without any surface loading due to its dilution. Tracer tests reveal high groundwater flow velocity Va values ranging from 82 m/h to 146 m/h due to the intense karst and the existence of caves. Groundwater flow present NE direction and the discharge of karst aquifer take place in the Tempi value. The recorded contamination within the recharge area of the karstic springs is directly connected to anthropogenic impacts and incomplete water collection infrastructure. Actions for the aquifer protection must be taken the soonest possible.

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Assessing the Spatiotemporal Evolution of Anthropogenic Impacts on Remotely Sensed Vegetation Dynamics in Xinjiang, China

Remote Sensing ◽

10.3390/rs13224651 ◽

2021 ◽

Vol 13 (22) ◽

pp. 4651

Author(s):

Jingyun Guan ◽

Junqiang Yao ◽

Moyan Li ◽

Jianghua Zheng

Keyword(s):

Human Activities ◽

Vegetation Dynamics ◽

Anthropogenic Impacts ◽

Stepwise Multiple Regression ◽

Anthropogenic Factors ◽

Vegetation Changes ◽

Evolutionary Trend ◽

Evolutionary Trends ◽

The World ◽

The Impact

The dynamics of the ecosystem represented by vegetation under the influence of human activities have become an important issue in the study of the regional ecological environment. Xinjiang is one of the most ecologically fragile areas in the world, and vegetation changes have received extensive attention. Xinjiang is one of the most ecologically fragile areas in the world, and vegetation changes have received extensive attention. However, the spatiotemporal patterns and evolutionary trends of anthropogenic impacts on vegetation dynamics in Xinjiang are still unclear. In this study, the anthropogenic impacts on vegetation dynamics were quantitatively assessed by combining the improved normalized difference vegetation index (NDVI) prediction model and the residual analysis method in Xinjiang, China. The human driving factors were analyzed with the support of a stepwise multiple regression model for vegetation changes at the county scale. Based on trend analysis and the Hurst exponent, the spatiotemporal characteristics and evolutionary trends of the impact of human activities on vegetation change were discussed. The results show that (1) the NDVI values in Xinjiang showed a gradually increasing trend at a rate of 0.005/10 years from 1982 to 2018, and the vegetation dynamics mainly showed significant improvements (57.09% of the vegetated areas), especially for crops. (2) The anthropogenic effects of vegetation changes in Xinjiang mainly included positive impact increases (43.22% of the vegetated areas) from 2000 to 2018. Human activities promoted the increase in the NDVI of various vegetation types. Both the positive and negative impacts of human activities increased over the study period, and the growth rate of the positive influence (0.08%/10 years) was higher than that of the negative influence (0.04%/10 years). (3) The cultivated area, GDP of primary industry, and population are the main anthropogenic factors causing the increase in NDVI, which dominate the vegetation greening in 30.34%, 29.22%, and 28.09% of the counties in Xinjiang, respectively. The animal husbandry population, agricultural population, and livestock number are the main anthropogenic factors causing the decrease in NDVI, which dominate the vegetation degradation in 23.60%, 21.35%, and 17.98% of the counties in Xinjiang, respectively. (4) The evolutionary trend of the anthropogenic impact on vegetation dynamics in Xinjiang will be dominated by anti-persistence (53.84% of the vegetated areas), thereby mainly showing that the positive impacts continued to increase (22.56% of the vegetated areas), especially for crops, shrubs, grasslands, and alpine vegetation. Our results are helpful in understanding the characteristics and evolutionary trends of vegetation changes in arid areas caused by human activities and are of significance as a reference for policymakers to appropriately adjust policy guidance in a timely manner to promote the protection and sustainable development of fragile ecosystems.

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Spatio-temporal dynamics of vegetation cover in North-West Algeria using remote sensing data

Polish Cartographical Review ◽

10.2478/pcr-2019-0009 ◽

2019 ◽

Vol 51 (3) ◽

pp. 117-127

Author(s):

Si Tayeb Tayeb ◽

Benabdeli Kheloufi

Keyword(s):

Remote Sensing ◽

Land Cover ◽

Human Activities ◽

Vegetation Cover ◽

Vegetation Index ◽

Temporal Dynamics ◽

Anthropogenic Impacts ◽

Regional Scale ◽

Anthropogenic Factors ◽

Spatio Temporal

Abstract Land cover change is the result of complex interactions between social and environmental systems which change over time. While climatic and biophysics phenomena were for a long time the principal factor of land transformations, human activities are today the origin of the major part of land transformation which affects natural ecosystems. Quantification of natural and anthropogenic impacts on vegetation cover is often hampered by logistical issues, including (1) the difficulty of systematically monitoring the effects over large areas and (2) the lack of comparison sites needed to evaluate the effect of the factors. The effective procedure for measuring the degree of environmental change due to natural factors and human activities is the multitemporal study of vegetation cover. For this purpose, the aim of this work is the analysis of the evolution of land cover using remote sensing techniques, in order to better understand the respective role of natural and anthropogenic factors controlling this evolution. A spatio-temporal land cover dynamics study on a regional scale in Oranie, using Landsat data for two periods (1984–2000) and (2000–2011) was conducted. The images of the vegetation index were classified into three classes based on Normalized Difference Vegetation Index (NDVI) values and analysed using image difference approach. The result shows that the vegetation cover was changed. An intensive regression of the woody vegetation and forest land resulted in -22.5% of the area being lost between 1984 and 2000, 1,271 km2 was converted into scrub formations and 306 km2 into bare soil. On the other hand, this class increased by around 45% between 2000 and 2011, these evolutions resulting from the development of scrub groups with an area of 1,875.7 km2.

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STUDYING OF TERSKO-SULAKSKAYA LOWLAND VEGETATION UNDER THE RESULTS OF GROUND-BASED RESEARCH AND AUTOMATED INTERPRETATION

Vestnik of the Russian agricultural science ◽

10.30850/vrsn/2020/2/29-32 ◽

1970 ◽

pp. 29-32

Author(s):

M. I. Dzhalalova ◽

A. B. Biarslanov ◽

D. B. Asgerova

Keyword(s):

Plant Communities ◽

Satellite Imagery ◽

Vegetation Cover ◽

Anthropogenic Impacts ◽

Species Abundance ◽

Remote Sensing Data ◽

Indigenous Communities ◽

The State ◽

Anthropogenic Factors ◽

Internet Resource

The state of plant communities in areas located in the Tersko-Sulak lowland was studied by assessing phytocenotic indicators: the structure of vegetation cover, projective cover, species diversity, species abundance and elevated production, as well as automated decoding methods. There are almost no virgin soils and natural phytocenoses here; all of them have been transformed into agrocenoses (irrigated arable lands and hayfields, rice-trees and pastures). The long-term impact on pasture ecosystems of natural and anthropogenic factors leads to significant changes in the indigenous communities of this region. Phytocenoses are formed mainly by dry-steppe types of cereals with the participation of feather grass, forbs and ephemera, a semi-desert haloxerophytic shrub - Taurida wormwood. At the base of the grass stand is common coastal wormwood and Taurida wormwood - species resistant to anthropogenic influences. Anthropogenic impacts have led to a decrease in the number of species of feed-rich grain crops and a decrease in the overall productivity of pastures. Plant communities in all areas are littered with ruderal species. The seasonal dynamics of the land cover of the sites was estimated by the methods of automatic decoding of satellite images of the Landsat8 OLI series satellite for 2015, dated by the periods: spring - May 20, summer - July 23, autumn - October 20. Satellite imagery data obtained by Landsat satellite with a resolution in the multispectral image of 30 m per pixel, and in the panchromatic image - 10 m per pixel, which correspond to the requirements for satellite imagery to assess the dynamics of soil and vegetation cover. Lower resolution data, for example, NDVI MODIS, does not provide a reliable reflection of the state of soil and vegetation cover under arid conditions. In this regard, remote sensing data obtained from the Internet resource https://earthexplorer.usgs.gov/ was used.

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First Application of the Integrated Karst Aquifer Vulnerability (IKAV) method. Potential and Actual vulnerability in Yucatan, Mexico

10.5194/nhess-2021-376 ◽

2021 ◽

Author(s):

Miguel Moreno-Gómez ◽

Carolina Martínez-Salvador ◽

Rudolf Lied ◽

Catalin Stefan ◽

Julia Pacheco

Keyword(s):

Transport Model ◽

Karst Aquifer ◽

Theoretical Models ◽

Groundwater Vulnerability ◽

Aquifer Vulnerability ◽

Environmental Damage ◽

Integrated Method ◽

Support Tools ◽

Vulnerability Maps ◽

Water Resources Protection

Abstract. Groundwater vulnerability maps are important decision support tools for water resources protection against pollution and helpful to minimize environmental damage. However, these tools carry a high subjectivity along the multiple steps taken for the development of such maps. Additionally, the theoretical models on which they are based do not consider important parameters such as pollutant concentration or pollutant residence time in a given section of the aquifer, solely focusing the analysis on a theoretical travel time from a release point towards a target. In this work, an integrated methodology for the evaluation of potential (intrinsic) and actual vulnerability is presented. This integrated method, named IKAV, was developed after the analysis of several study cases and the application of multiple intrinsic groundwater vulnerability methods in a selected study area. Also, a solute transport model served as the basis to define additional parameters for vulnerability analysis for areas severely affected by anthropogenic practices. A defined workflow and several criteria for parameters and attributes selection, rating and weighting assignment, and vulnerability classification are presented. The first application of the IKAV method was carried out in the Yucatan karst, demonstrating to be a reliable method for vulnerability estimation. Results demonstrated the scope of the IKAV method to highlight important regional conditions, minimizing the subjectivity, and expanding the analysis of vulnerability.

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Vulnerability Assessment as a Basis for Sanitary Zone Delineation of Karst Groundwater Sources—Blederija Spring Case Study

Water ◽

10.3390/w13192775 ◽

2021 ◽

Vol 13 (19) ◽

pp. 2775

Author(s):

Vladimir Živanović ◽

Nebojša Atanacković ◽

Saša Stojadinović

Keyword(s):

Vulnerability Assessment ◽

Groundwater Vulnerability ◽

Assessment Method ◽

Karst Groundwater ◽

Karst Spring ◽

Aquifer Recharge ◽

Protection Zones ◽

Groundwater Vulnerability Assessment ◽

Vulnerability Maps ◽

Dependent Model

The application of groundwater vulnerability methods has great importance for the sanitary protection zones delineation of karstic sources. Source vulnerability assessment of karst groundwater has mainly relied on the European approach (European Cooperation in Science and Technology—COST action 620), which includes analysis of the K factor, which refers to water flow through the saturated zone of the karst system. In the paper, two approaches to groundwater vulnerability assessment have been applied, COP + K and TDM (Time-Dependent Model) methods, to produce the most suitable source vulnerability map that can be transformed into sanitary protection zones maps. Both methods were tested on the case example of Blederija karst spring in Eastern Serbia. This spring represents a classical karst spring with allogenic and autogenic recharge. Dual aquifer recharge points out the necessity for the inclusion of the vulnerability assessment method created especially for the assessment of karst groundwater. Obtained vulnerability maps show similar results, particularly in the spring and the ponor areas, and these zones are most important for future protection. The COP + K method brings out three vulnerability classes that can be directly transformed into three sanitary protection zones. Contrary to the previous one, the TDM method uses water travel time as a vulnerability degree. The results show that the final map can be easily used to define sanitary zones considering different national legislation.

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Anthropogenic Influences on Environmental Changes of Lake Bosten, the Largest Inland Freshwater Lake in China

Sustainability ◽

10.3390/su12020711 ◽

2020 ◽

Vol 12 (2) ◽

pp. 711 ◽

Cited By ~ 4

Author(s):

Wen Liu ◽

Long Ma ◽

Jilili Abuduwaili

Keyword(s):

Central Asia ◽

Lake Sediments ◽

Human Activities ◽

Environmental Changes ◽

Living Environment ◽

Water Levels ◽

Aral Sea ◽

Anthropogenic Factors ◽

Large Spatial Scale ◽

The 1960S

A short lacustrine sediment core (41 cm) from Lake Bosten in arid central Asia was used to investigate the environmental changes that occurred in the past ≈150 years based on the superposition of climate and anthropogenic factors. Geochemical elements, total organic carbon (TOC) and nitrogen (TN), and stable isotope data (δ13Corg and δ15N) were used to identify abnormal environmental changes. The average C/N ratio in the sediments of Lake Bosten suggested that the organic matter in lake sediments was mainly from aquatic plants. The δ13Corg and δ15N in the lake sediments mainly reflect changes in the structure of the lake’s ecosystem. Before the 1960s, the primary productivity of the lake was relatively low with a relatively stable lake water environment. From the 1960s to the mid-1980s, the lake’s ecosystem was closely related to a significant decline in water levels caused by human activities and an increase in salinity. From the late 1980s to ≈2000, the aquatic plant structure of Lake Bosten did not change significantly. After 2000, the upper part of the sedimentary record suggested enhanced productivity due to urban and industrial development in the catchment area. However, sedimentary perspectives of the responses of different environmental proxies in sediments to human activities were anisochronous, and the increasing heavy metal (Pb and Cu) and P accumulations appeared in 1970, reflecting heightened human impacts. Through the comparison between the Aral Sea and Lake Bosten, it was inferred that, under the intervention of human activities, the lake experienced a completely different evolution trend. Humans, as geological agents, should protect our living environment while satisfying social development. The results will provide an important supplement to a large spatial scale study of the influences of human activities on the environment in Central Asia, which also has some significant implications for the protection of the ecological environment and the realization of sustainable development in arid regions.

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Changes in the Historical and Current Habitat Ranges of Rare Wild Mammals in China: A Case Study of Six Taxa of Small- to Large-Sized Mammals

Sustainability ◽

10.3390/su12072744 ◽

2020 ◽

Vol 12 (7) ◽

pp. 2744

Author(s):

Tianlu Qian ◽

Yao Chi ◽

Changbai Xi ◽

Zhongqiu Li ◽

Jiechen Wang

Keyword(s):

Human Activities ◽

Anthropogenic Impacts ◽

Mainland China ◽

Negative Influence ◽

Asian Elephant ◽

Environmental Data ◽

Climate Data ◽

Entropy Model ◽

Activity Data ◽

Wild Mammals

Through history, the habitats of wild mammals have changed greatly in China. Habitat changes may reflect changes in the environment and human–wildlife conflicts. This study focused on how the habitat changed for six taxa of rare wild mammals (one family, one genus, and four species) in mainland China. Their historical and current habitats were estimated according to their historical and current presence occurrences and three sets of environmental data (climate data, topography data, and human activity data), using the Maximum Entropy Model. Then, spatial statistical methods were used to analyze the changes in their habitats, and how human activities have influenced changes in their habitat. The results suggest that the habitats of all six taxa of mammals have shrunk considerably, compared to their historical ranges. With regards to current or past habitats, on average, 68.3% of habitats have been lost. The Asian elephant, which is facing the most serious habitat losses, has lost 93.1% of its habitat. By investigating the relationship between the changes in habitats and the anthropogenic impacts for each taxa, human activities have an obvious negative influence on mammal habitats. The sensitivity of habitats to human activities varies among different mammals: the tiger, Asian elephant, Bactrian camel, and snub-nosed monkey are more sensitive to human activities than musk deer and Chinese water deer.

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