Capitulo: Municipio de la Paz. Aspectos Generales

Abstract

Obligate subterranean fauna as well as many other categorical subterranean species (troglophiles and trogloxens) rely heavily on subterranean habitats and thus are highly vulnerable to threats that result in environmental change and habitat disturbance and degradation. These threats vary with respect to scope, source, severity, and timing among species, karst regions and continents. Some threats, such as climate change and groundwater pollution, are global in scope (Culver & Pipan 2009). However, effects of climate change and sources of groundwater pollution vary at regional and local scales. Other threats affect subterranean populations and species at a local or regional scale, for instance mining and quarrying, groundwater extraction, and amateur and scientific collection could severely damage these habitats. Several life history traits are common to many troglobionts, and to some extent, are associated with increased risk of extinction, including low reproductive rates and limited dispersal ability. Thus, population rescue is often much slower and risk of extinction much greater relative to populations of related Surface species. Besides, many troglobionts may be particularly sensitive to small fluctuations in abiotic variables such as temperature, humidity, dissolved oxygen, and concentrations of heavy metals, among others. Consequently, any disturbance during hibernation or when females are raising their breed can have long-lasting damaging effects on recruitment and survival of local populations. In South America there are at least three cave systems with high diversity of troglobionts (Deharveng & Bedos 2012). More recently, four cave systems have been identified as spots of troglobitic fauna in Brazil: Areias Cave System (24+ troglobionts), Alambari Cave System (16 species), Parede Vermelha Cave (12+ species) and Olhos Dágua Cave (11+ species) (Trajano et al., 2016). Despite these biological factors and many documented and suspected threats, only a small fraction of subterranean biodiversity receives any direct protection under international, national, or regional legislation. Compared to vertebrates, subterranean invertebrates and other organisms have largely been neglected in conservation studies, assessments, and policy decisions, despite their significantly greater diversity, roles in groundwater and subterranean ecosystem services, sometimes higher in levels of endemicity and benefits to mankind.