Seasonal variations in cave invertebrate communities in the semiarid Caatinga, Brazil

Abstract

The Brazilian semiarid region has a clear distinction between the dry season, which can last up to nine months, and the rainy season. Caves are connected to different extents to surface ecosystems, although they are idealized as stable environments due to their isolation. Furthermore, little is known about the effects of wet and dry seasonal variations on underground biological assemblages. Invertebrate communities were analyzed during dry and rainy seasons in 24 caves in the semiarid region of northeastern Brazil. We also investigated whether the environmental stability of caves attenuates the effects of seasonality in this particular region. Morphospecies richness and abundance and the diversity indexes of caves were significantly higher during the rainy season. In addition, more stable caves showed less variation in the community composition between seasons. Our data point to a clear influence of the surface ecosystems on the caves in Caatinga. However, the intensity of this influence apparently depends on the environmental stability of the cave, and the most stable caves present smaller changes in the structure of their invertebrate communities during different seasons.

Distributional dynamics of a specialized subterranean community oppose the classical understanding of the preferred subterranean habitats

“…Subterranean habitats are suitable for studying species interactions, ecological niches, and temporal and spatial patterns in terrestrial subterranean communities. However, subterranean communities as a whole are only rarely considered in relation with environmental conditions (e.g., Bento et al, ; Di Russo et al, ; Mammola & Isaia, ; Mammola et al, ; Pipan et al, ; Sendra & Reboleira, ; Tobin et al, ). Consequently, community responses to environmental conditions are still poorly understood.…”

“…So far, subterranean habitats have been investigated for their environmental conditions in relation to their associated fauna (e.g., Bento et al, ; Culver & Pipan, ; Lunghi, Manenti, & Ficetola, , ; Mammola et al, ; Mammola et al, ; Pipan, ; Prous et al, ; Tobin et al, ). Distributional dynamics of subterranean fauna, especially troglobionts, have rarely been studied.…”

Finding answers in the dark: caves as models in ecology fifty years after Poulson and White

“…species exploiting subterranean habitats in certain phases of their life cycle (Diesel et al 1995, Polak 1997, Culver and Sket 2002, Glover and Altringham 2008, Novak et al 2010a, Chelini et al 2011, Polseela et al 2011, Baker 2015, Lipovšek et al 2016. As a direct consequence, there can be conspicuous temporal turnovers in the species composition in a typical subterranean community (Nitzu et al 2011, Bento et al 2016, Yun et al 2016, Bichuette et al 2017, especially in the vicinity of the surface (Rendoš et al 2012) which should be taken into account when designing ecological studies and sampling protocols (Culver and Sket 2002, Meleg et al 2015, Wynne et al 2018). For instance, different arthropods may actively move from larger cave chambers to the stable network of fissures and vice versa (Chapman 1985), or rearrange their spatial distribution along the cave length in different seasons (Crouau-Roy et al 1992, Mammola et al 2015a, 2017a, Lunghi et al 2017.…”

“…For instance, different arthropods may actively move from larger cave chambers to the stable network of fissures and vice versa (Chapman 1985), or rearrange their spatial distribution along the cave length in different seasons (Crouau-Roy et al 1992, Mammola et al 2015a, 2017a, Lunghi et al 2017. As a direct consequence, there can be conspicuous temporal turnovers in the species composition in a typical subterranean community (Nitzu et al 2011, Bento et al 2016, Yun et al 2016, Bichuette et al 2017, especially in the vicinity of the surface (Rendoš et al 2012) which should be taken into account when designing ecological studies and sampling protocols (Culver and Sket 2002, Meleg et al 2015, Wynne et al 2018).…”

The Impact of Lampenflora on Cave-dwelling Arthropods in Gunungsewu Karst, Java, Indonesia

“…Cave has unique environmental characters that support difference ecosystem condition. This environment is characterized by the permanently absence of light, high air humidity, stable temperature, high CO 2 and often limited food resources (Bento et al, 2016;Palacios-Vargas et al, 2011;Simões et al, 2015) In the term of biodiversity and dominancy, undisturbed cave ecosystem has an opposite conditions with the general ecosystem condition that mentioned before. Cave ecosystem relatively possesses less species diversity and generally dominated by particular species that have evolved to adapt in these extreme condition (Culver & Pipan, 2009).…”