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6 páginas.-- 2 figuras.-- 44 referencias ; The ecology and conservation state of fossorial herpetofauna is poorly understood but they may be at particular risk from soil disturbance. However, their low conspicuousness may lead conservationist researchers and managers to overlook potential problems. Amphisbaenians are a group of fossorial reptiles but, because of their secretive habits, there are few data on their ecology and potential conservation problems. Here, we examined the effects of an anthropogenic factors (alteration of rocks by whitewashing), which affects chemical properties of the soil, on body condition of fossorial Trogonophis wiegmanni amphisbaenians. Results indicated that the increased amounts of inorganic carbonates under whitewashed rocks may negatively affect the body condition of amphisbaenians, their fitness, and the health of the populations. We suggest potential management actions to solve this problem and emphasize the need for periodic surveys of subterranean herpetofauna to prevent future conservation problems. © 2017. José Martín All Rights Reserved. ; Legal authorization and financial support was provided by the Organismo Autónomo de Parques Nacionales, with additional financial support from a Ministerio de Ciencia e Innovación project (CGL2011-24150/BOS) and from the Regional Government of Andalusia project BIOGEOBIRD (P09-RNM-4987) and FEDER funds. ; Peer reviewed

Soil alteration is one of the major threats in arid environments, which can have serious consequences for soil biodiversity. However, the ecology of fossorial animals is poorly understood and their low conspicuousness may lead researchers and managers to overlook potential conservation problems. Amphisbaenians are fossorial reptiles and, because of their secretive habits, there is a chronic almost lack of data on their conservation state. Here, we examined the effects of diverse natural (salinization and seagulls influence) and anthropogenic factors (disturbance of the soil physical structure and lead contamination) that affect physical and chemical properties of the soil on body condition of Trogonophis wiegmanni amphisbaenians from the Chafarinas Islands, in North Africa. Results indicated that soil salinization and human induced mechanical disturbance and compaction of the soil affected negatively to body condition of amphisbaenians. In contrast, the increase in organic matter and heavy metals pollutants in the soil, either because of the seagull or anthropogenic influence, did not seem to affect body condition of amphisbaenians. We suggest potential management techniques to solve these problems and emphasize the need for periodic surveys of subterranean herpetofauna to prevent future conservation problems. ; Legal authorization and financial support was provided by the Organismo Autónomo de Parques Nacionales with additional financial support from a Ministerio de Ciencia e Innovación project (CGL2011-24150/BOS) and from the Regional Government of Andalusia project BIOGEOBIRD (P09-RNM-4987) and FEDER funds. ; Peer reviewed

ABSTRACT: Customer overall satisfaction regarding a public transport system is dependent on the satisfaction of the users with the attributes that make up the service, as well as the contribution that each of these attributes makes to explain the overall satisfaction. A common way of analysing the contribution of service attributes to explain overall satisfaction is through the use of ordered logit or probit models. This article presents an ordered logit model that considers the weighting of independent variables through the explicit importance calculated on the basis of a best-worst case 1 choice task. For the calculation of importance, a multinomial logit model has been estimated which considers the heterogeneity of the sample through systematic variations in user tastes. In this way, it is possible to establish a level of importance of each specific attribute for each type of user. The results show that the importance varies considerably depending on different socio-economic and mobility-base variables. On the other hand, the inclusion of the weighted variables in the ordered logit model improves its fit. Therefore, the results make possible to develop policies focused on improving satisfaction on specific user targets ; This research was funded by the Spanish Ministry of Economy and Industry in the TRA2015-69903-R Project (co-funded with ERDF funds), by the training grant FPU15/02990 of the Spanish Ministry of Education, Culture and Sports, and by European Research Council (ERC) under the European Union's Horizon 2020 research and innovation programme (grant agreement No 688082—SETA Project).

Colonial nesting and roosting birds can degrade their habitat by soil salinization, eutrophication, and acidification associated with excessive deposition of avian excreta. We studied the impact of a protected wading bird colony on soil microbial communities from cork oak woodlands in Doñana National Park (SW Spain). Over one year we analyzed soil properties (pH, salinity, soluble N and P forms, extractable organic carbon - EOC -), microbial activity (basal respiration, community-level physiological profile, extracellular enzyme activities) and community structure (fungal, bacterial and archaeal terminal restriction fragments -TRFs-) along a gradient of bird nesting intensity. Bird nesting largely impacted soil chemical environment, with increases from 25 to 500 μS cm−1 in soil salinity, from 6 to 725 mg kg−1 in soil P, from 5 to 22 mg kg−1 in N-NH4, and from 5.4 to 245 mg kg−1 in N-NO3 between the extremes of the nesting intensity gradient in the wet season. Most of these chemical changes were enhanced in the dry season. We observed positive linear or log-linear relationships between the bird nesting footprint on soils (indicated by an integrated soil chemistry index) and microbial biomass, basal respiration and most of the studied enzyme activities. This was likely due to the concurrent increases in EOC along the avian intensity gradient, which counteracted the negative impacts of salinity. Soil P and EOC were the main drivers for fungal, bacterial and archaeal TRFs diversity. Bacterial TRFs richness and diversity index decreased along the avian intensity gradient in the dry season, while archaeal TRFs diversity increased in those soils highly salinized by excess of avian excreta deposition. Our study clearly shows that this oversized bird colony has profound effects on soil chemistry and biological activity, and highlights the need for a re-evaluation of management strategies in this protected area, towards a greater consideration of soil processes in conservation priorities. ; We are grateful to the Consejería de Medio Ambiente (Andalusian Government) and to the Organismo Autónomo Parques Nacionales for financial support, through the DECALDO (091/2009) and the BIOGEOBIRD (P09-RMN-4987) projects, and to the Doñana National Park and Doñana Biological Reserve managers for the use of their facilities and the support to carry out the field work. Rubén Rodríguez and Héctor Garrido from the Doñana Monitoring Team provide us with data of cork oak occupation by the colony. We also thank Adela Moreno fir her work with T-RFLP analysis. MTD was supported by a Juan de la Cierva Postdoctoral fellowship and JMA by a FPU-MEC grant from the Spanish Ministry of Economy and Competitiveness. ; Peer reviewed