A cost‐effective model for preliminary site evaluation for the reintroduction of a threatened quillwort

Abstract

ABSTRACT1. The choice of suitable sites for establishment of a new population of a species is the first step in a translocation programme. However, evaluation of a large number of sites can be demanding of time and money; practitioners need time-and costeffective evaluation tools.2. A predictive model for the preliminary evaluation of potential reintroduction sites was developed using the endangered quillwort Isoëtes malinverniana as a case study. The reliability of three water habitat variables (pH, conductivity, and clarity) as predictors of the presence/absence of I. malinverniana was tested. Three sets of logistic models were produced on the basis of the mean values of pH and conductivity measured over 3, 4 and 6 months to understand whether frequency of measurement affected the reliability of the models. Models of each set were ranked according to AIC and their reliability was then tested using data from the literature.3. The conductivity of water and pH were the most effective predictors of the suitability of sites for the reintroduction of I. malinverniana. In particular there was a negative relationship between the presence of I. malinverniana and these variables.4. Because of seasonal fluctuations in the variables considered, at least 4 months monitoring are required to obtain reliable results. Despite this, the method is still advantageous in terms of costs, compared with repeated measurements of a wide range of chemical characteristics at a large number of sites.5. The main goal of this method is to limit expensive chemical analysis to a few sites chosen after the exclusion of unsuitable sites, through application of the model.Considering the similar ecophysiological features of quillworts from oligotrophic waters, the same model or conceptual framework could be applied to other quillworts and isoetid species growing in degraded areas and needing active conservation.2

Estimating influence of environmental quality and management of channels on survival of a threatened endemic quillwort

“…Although we cannot exclude the combined contribution of the increase in temperature with other environmental parameters, we lack evidence of a direct detrimental effect of water warming on Isoëtes occurrence. On the contrary, conductivity has been often reported as an important factor determining Isoëtesgrowth and thus was considered a useful parameter to identify habitat suitability for aquatic quillworts ( Vöge, 2003, Abeli et al, 2012. Increased values of conductivity in EX-ISO sites may be both related to higher temperature values and to greater amount of ionized solutes and/or total dissolved solid, compared to ISO sites.…”

Predicting aquatic macrophyte occurrence in soft-water oligotrophic lakes (Pyrenees mountain range)

“…Logistic models can help to better understand species occurrence and responses to environmental factors van Nes et al, 2003;Abeli et al, 2012) and are able to predict the probability of occurrence of a species as a function of a single or multiple environmental variables. This approach allows us to both define the autoecology of the species and to predict their occurrence in a lake, which is a valuable tool to assist in the conservation and the restoration of the assemblages of aquatic macrophytes, especially in those systems with incomplete records of former macrophyte populations or that may require of species introduction due to isolation or lack of recruitment.…”

Deleterious interaction of light impairment and organic matter enrichment on Isoetes lacustris (Lycopodiophyta, Isoetales)

“…NF no fertilization, F fertilization levels were not significant, suggesting limitation in leaf length as described in other isoetids (Madsen et al, 2002) to maintain lacunae CO 2 transport towards the leaf tips. Light reduction, at least to these levels, seems to play a secondary role for Isoetes growth and survival as also seen by Abeli et al (2012).…”