Environmental isotope applications in Latin America and the Caribbean region

Abstract

This Special Issue illustrates the use of environmental isotopes in studying and assessing hydrogeological and ecohydrological issues in the Latin America and the Caribbean (LAC) region. The issue includes twenty selected papers, which have been peer-reviewed in Isotopes in Environmental and Health Studies. Although the LAC region concentrates a third of the world's freshwater resources [1], access to safe water supplies and sanitation remains unevenly distributed, with water scarcity affecting most arid and semiarid areas and serious water quality issues across the region [2]. About 82% of the LAC population lives in urban centres, including some megacities, creating major challenges to water authorities [3]. Water security is often compromised due to a fast-growing water demand near urban centres (i.e. domestic supply, irrigation and industrial uses) along with the expected impacts of climate change [4] on both water availability and quality [5-7]. In many parts of the LAC region, groundwater resources have become the main or the only source of water to cover basic human needs and the maintenance of ecosystems [8-10]. This rapid increase of water demand is generally translated into intensive and unsustainable exploitation of water resources, having a profound impact on local hydrological cycles. In order to assess the availability of local resources for the near future and adopt sustainable management practices, sound and precise hydrological information is required. Stable (2 H, 13 C, 15 N, 18 O, 87 Sr) and radioactive (3 H, 7 Be, 14 C, 210 Pb, 222 Rn) environmental isotopes can provide unique and valuable information required for the assessment and comprehensive management of water resources and for understanding the complex interactions between terrestrial ecosystems (i.e. soil, vegetation) and the hydrological cycle. Isotope hydrology tools and methods have been used to characterise both surface and ground water systems, study recharge processes from rainfall generation to infiltration, coastal aquifers, major lakes and river basins as well as in assessing lake dynamics, geothermal fields, dam leakage problems, and evapotranspiration partitioning [11]. However, the incorporation of these applications in LAC has not been fully implemented yet. To date, there is a relatively small number of case studies published from a limited number of institutes and universities, often through the assistance and support provided since the 1980s by the International Atomic Energy Agency (IAEA) or through bilateral cooperation with other international agencies. The pressing need in recent years to better describe and understand our natural systems, coupled with the easier access to analytical instrumentation [12], has resulted in the establishment and consolidation of many research groups in the LAC region using environmental isotopes to study hydrological and ecological systems. Therefore, the region has made steady progress over the last years to train a new generation of experts in hydrology and ecology with courses and w...

Current approaches to acute postoperative pain management after major abdominal surgery: a narrative review and future directions

“…Perioperative lidocaine administration protocols vary widely and remain controversial, necessitating due consideration for dosing strategies to ensure patient safety. 27,28 Dosing strategies should consider patient weight, the impact of anaesthesia on hepatic blood flow, variations in protein binding, non-linear pharmacokinetics associated with infusions, and exposure to interacting medications, especially those patients taking moderateestrong inhibitors of the CYP1A2 and CYP3A4 metabolic pathways within 72 h before surgery (see Table 1: antibiotics [especially the 'mycin', 'floxacin' class], antifungals, antiretrovirals, antidepressants, calcium channel blockers, monoclonal antibodies, and other strong cytochrome P450 3A4 inhibitors).…”

Geodiversity influences limnological conditions and freshwater ostracode species distributions across broad spatial scales in the northern Neotropics

“…Currently, most aquatic environments in the northern Neotropics are used as potable water sources and for agriculture; in large lakes, fishing and aquaculture have caused eutrophication and introduced invasive species (e.g., Oreochromis niloticus). In addition, some lakes located close to urban centers and farmlands are used as disposal sites for waste waters, agrochemicals, and mine residues (McKaye et al, 1995;Soto et al, 2020). The high heterogeneity of geodiversity in the northern Neotropics, and the poor knowledge of the limnological conditions of aquatic ecosystems in the region make it difficult to (1) understand the complex relations among geodiversity, water-column physicochemical variables, and biological characteristics (community composition and species richness), and (2) distinguish different limnological regions and determine their geographic coverage.…”

Geodiversity primarily shapes large-scale limnology and aquatic species distribution in the northern Neotropics

“…Oreochromis niloticus). In addition, it is common that lakes are used as final dispose sites of waste waters, agrochemicals and mining residuals (McKaye et al, 1995;Soto et al, 2020).…”