Publication Schedule By transitioning to a predominantly electronic distribution, we have been able to control and reduce costs incurred by the National Speleological Society to produce and ...distribute individual issues of the Journal. Because we feel this is such an important improvement, we decided to not wait until the new year to implement this change. The new format has been designed to improve online viewing and readability, to maintain a professional quality and look that is consistent with peer publications, and to reduce our production time.
In the past 20 years, karst desertification control has produced remarkable results, and the South China karst has been a global hotspot for greening. However, in the new stage of karst ...desertification control, the functional lag of forest ecosystems and the insufficient supply capacity of ecosystem services are gradually becoming prominent. We not only lack systematic research on vulnerability and resilience, structure and stability, ecological assets and services, carrying capacity and ecological security, and service trade-offs/synergies and optimization in controlled ecosystems. There is still a lack of research on the ecological processes of newly constructed forests in improving ecosystem functions and services. Therefore, this reprint mainly focuses on the research improvement of forest ecosystem functions in karst desertification control. This includes the improvement mechanism of ecosystem structure, function, and services, the mechanism of ecosystem service tradeoff/synergy, and function optimization. An optimization model of ecosystem function and an improvement path for eco-product supply are introduced. The role of functional traits in the maintenance of ecological function and services is also established, and social–ecological responses to afforestation in karst desertification control are discussed.
Resumen Times 12 Alrededor del 10% de la superficie de tierra en el mundo está ocupada por sistemas kársticos (Bakalowicz, 2005), de gran importancia porque muchas veces contienen agua subterránea ...que puede ser utilizada para abastecimiento. Los acuíferos de estos sistemas son los más susceptibles a la contaminación debido a sus altas velocidades de flujo y a que los procesos de atenuación son nulos o poco eficientes (Duarte, 2016). Para la valoración de la vulnerabilidad ante esta contaminación existen dos enfoques, el hidropedológico y el geomorfológico de los cuales deriva una lista importante de metodologías. Estas metodologías, desarrolladas desde 1995, tienen un fuerte componente hidrogeológico (Aguilar Duarte et al., 2016). El Índice IVAKY tiene un enfoque geomorfopedológico ya que integra espacialmente, elementos ambientales (relieve, suelo y clima) determinantes en la interpretación de la vulnerabilidad del acuífero. El objeto de este trabajo es presentar el mapa de vulnerabilidad a la contaminación del acuífero en el municipio de Bacalar, Quintana Roo, utilizando la metodología del Índice IVAKY (Índice de Vulnerabilidad del Acuífero Kárstico Yucateco) elaborada por Aguilar Duarte et al. (2016). El municipio de Bacalar es de reciente creación (año 2011) y tiene una superficie de 7,161.1 kilómetros cuadrados (17% del total estatal). Dentro de sus límites se encuentran varios cuerpos de agua tales como la Laguna de Bacalar, que tienen importantes aportes del acuífero. La profundidad promedio del acuífero en la región es de 5 metros. Por lo tanto, dicho acuífero debe estar sujeto a un especial cuidado por su fragilidad y exposición (Universidad de Quintana Roo, 2005) En el cálculo se utilizaron fuentes oficiales de información: para la caracterización geomorfológica de las depresiones kársticas (Fragoso-Servón, Bautista, Frausto, & Pereira, 2014), de la cual se obtiene el factor kárstico, el mapa de isohipsas escala 1:50,000 y para el factor edáfico, el mapa edafológico escala 1:250,000 ambos del Instituto Nacional de Estadística Geografía e Informática (INEGI); para el factor climático, la precipitación y evapotranspiración mensual se obtuvieron de las estadísticas de las estaciones meteorológicas del Servicio Meteorológico Nacional (SMN), las cuales fueron interpoladas para obtener las zonas con una duración similar del periodo de lluvias en el año (DPLL). El DPLL se define como el número de meses en los que la precipitación es mayor a la mitad de la evapotranspiración (DPLL=PP>EP*0.5). De acuerdo a la clasificación de Depresiones Kársticas, la zona con mayor densidad se encuentra cercana a la Laguna de Bacalar y desde ahí hacia el norte del municipio, otra zona con una densidad alta es la cercana a la costa. En el municipio, el 35% de los suelos son de tipo Leptosol rendzico asociado principalmente a Vertisoles y Gleysoles. Los leptosoles son suelos jóvenes, poco profundos, pedregosos y de drenaje libre; por lo que su potencial de filtración a la contaminación es muy poco. Los vertisoles ocupan el 24% de la superficie municipal, estos suelos tienen buenas propiedades de retención de agua. El periodo de lluvia más extenso es de 8 meses y se presenta en la zona cercana a la línea de costa, este periodo se registra de junio a diciembre de cada año. Para obtener el IVAKY fueron calificados los factores (relieve kárstico, edáfico, climático) de acuerdo a la metodología descrita por Aguilar Duarte et al. (2016) donde se emplea la siguiente formula: IVAKY=(0.65*karst)+(0.29*suelo)+(0.05*clima). Los resultados señalan que el 24% de la superficie del municipio tiene una vulnerabilidad media a la contaminación del acuífero, que se distribuye desde el sur y con una tendencia hacia el noroeste. La zona con vulnerabilidad de Muy baja a Baja (16%) se encuentra al oeste del municipio, donde la altitud esta entre los 100 y los 265 metros y donde los suelos dominantes son los Vertisoles, Regosoles y Phaeozem. Las zonas con una vulnerabilidad más alta (60%) son aquellas donde la densidad de depresiones es más alta, la altitud promedio es de 15 metros y los suelos dominantes son los Leptosoles y Luvisoles. Estas zonas se encuentran en la parte central del municipio y otra, de menor extensión, cercana a la línea de costa. Generalmente, las depresiones kársticas sufren inundaciones en el periodo de lluvias, por lo que un próximo paso es relacionar estas inundaciones con los efectos adversos que pueden ocasionar en las actividades económicas establecidas en zonas con una mayor densidad de ellas. En el municipio, el acuífero no se encuentra sobreexplotado y la calidad del agua en él es buena (Gobierno del Estado de Quintana Roo, 2013), por lo que el conocimiento y cuidado del mismo es crucial en etapas previas al desarrollo, como la que se está dando partir de su creación y el incentivo a actividades económicas.
This reprint encompasses karst ecosystem quality, ecosystem services, climate change, ecological restoration, vegetation dynamics, land management, and the element biogeochemical cycle. These are ...closely related to land system science, landscape, land–climate interactions, the water–energy–land–food nexus, ecosystem services, and multifunctionality and sustainability. We expect that this reprint will contribute to ecological construction and land use management in karst areas.
This paper gives a comprehensive explanation of the hydrogeological and hydrological characteristics of different water occurrence, which exists in the extremely complex Dinaric karst system. The ...area and boundaries of the Dinaric karst have never been precisely determined. It covers about 60,000 km² stretching the length of the eastern coast of the Adriatic Sea, from the Bay of Trieste in the north, to the Drim River basin in the south, and the Western Morava River valley in the east. Due to very high infiltration rates, overland and surface flows are rare in comparison with non-karst terrains. The Dinaric karst is an extremely heterogeneous medium which can be explained only by the use of a great number of measurements points and by continuously monitoring and measuring different parameters. The hydrogeological and hydrological regime of all water phenomena in the Dinaric karst depends mostly upon the interaction between groundwater and surface water. The dominant flow of the groundwater contained in the Dinaric karst is towards the Adriatic Sea through rivers and many permanent and intermittent coastal and submarine springs. The paper presents many examples of karst water phenomena from the Dinaric karst: (1) springs (Jadro, Ombla and Crnojevića Springs); (2) open streamflows (Ljubljanica, Pazinčica, Dobra, Lika, Gacka, Krka, Zrmanja and Cetina Rivers); (3) lakes and wetlands (Cerknica, Vrana, Plitvice, Vransko, Red and Blue Lakes); and (4) coastal and island karst (Brač Island).
Karst aquifers contribute substantially to freshwater supplies in many regions of the world, but are vulnerable to contamination and difficult to manage because of their unique hydrogeological ...characteristics. Many karst systems are hydraulically connected over wide areas and require transboundary exploration, protection and management. In order to obtain a better global overview of karst aquifers, to create a basis for sustainable international water-resources management, and to increase the awareness in the public and among decision makers, the World Karst Aquifer Mapping (WOKAM) project was established. The goal is to create a world map and database of karst aquifers, as a further development of earlier maps. This paper presents the basic concepts and the detailed mapping procedure, using France as an example to illustrate the step-by-step workflow, which includes generalization, differentiation of continuous and discontinuous carbonate and evaporite rock areas, and the identification of non-exposed karst aquifers. The map also shows selected caves and karst springs, which are collected in an associated global database. The draft karst aquifer map of Europe shows that 21.6% of the European land surface is characterized by the presence of (continuous or discontinuous) carbonate rocks; about 13.8% of the land surface is carbonate rock outcrop.
Karst aquifers are one of the main potable water sources worldwide. Although the exact global karst water utilisation figures cannot be provided, this study represents an attempt to make an upgraded ...assessment of earlier and often circulated data. The main objective of the undertaken analysis is not only to provide an assessment of the utilisation of current karst aquifers, but also to estimate possible trends under various impact factors such as population growth or climate changes. In > 140 countries, different types of karstified rocks crop out over some 19.3 × 10
6
km
2
, covering > 14% of ice-free land. The main ‘karst countries’, those with > 1 × 10
6
km
2
of karst surface are Russia, USA, China and Canada, while among those with > 80% of the territories covered by karst are Jamaica, Cuba, Montenegro and several others. In contrast, in a quarter of the total number of countries, karstic rocks are either totally absent or have a minor extension, meaning that no karst water sources can be developed. Although the precise number of total karst water consumers cannot be defined, it was assessed in 2016 at approximately 678 million or 9.2% of the world’s population, which is twice less than what was previously estimated in some of the reports. With a total estimated withdrawal of 127 km
3
/year, karst aquifers are contributing to the total global groundwater withdrawal by about 13%. However, only around 4% of the estimated average global annually renewable karstic groundwater is currently utilised, of which < 1% is for drinking purposes. Although often problematic because of unstable discharge regimes and high vulnerability to pollution, karst groundwater represents the main source of potable water supply in many countries and regions. Nevertheless, engineering solutions are often required to ensure a sustainable water supply and prevent negative consequences of groundwater over-extraction.
Electrical conductivity (EC) of karst spring discharge has always been a fundamental variable to characterize karst systems. However, to incorporate EC into the lumped hydrologic modeling is ...challenging but has a huge potential since EC observations are widely collected. In this study, we present a new framework to integrate EC into lumped karst hydrological models for model structure identification and parameter uncertainty reduction. Our framework is tested in a small, well‐instrumented karst catchment near Guilin city (China) where EC dynamics are mostly controlled by the dissolution of carbonate rock and dilution by event water. Four karst models with different structures were equipped to consider the linear growth of EC with the carbonate rock dissolution and its mixing within the karst system. Applying a parameter estimation framework that accounts for uncertainty in discharge and EC simulations, we find that all hydrologic models obtain similar performances concerning spring discharge. However, their performances in simulating spring EC strongly differ permitting us to identify the most realistic model out of the four model structures. Our analysis further shows that including EC into parameter estimation reduces parameter uncertainty concerning concentrated flow in the conduits and helps to estimate immobile water storage in the system. Consequently, our new framework to include EC in karst models provides new directions for the more realistic simulation that can easily be transferred to other karst systems where EC dynamics are controlled by rock dissolution and dilution by event water.
Key Points
A new framework to integrate electrical conductivity (EC) observations into lumped karst hydrologic models is presented
Spring EC shows a high potential for more realistic modeling
Incorporation of spring EC in models can reduce parameter uncertainty concerning concentrated flow in the conduits