Supplementary Material from Future effects of climate and land-use change on terrestrial vertebrate community diversity under different scenarios

Supplementary text giving full details of the methods, and supplementary figures and table

A comparison of broad-scale model estimates with independent bird data from East-Africa

Poster for SCCS 2016 conference in Cambridge.<br

African species response to land use change: Assessing the match between an Africa-wide model and fine-scale field data

<p>Anthropogenic land-use change is known to have severe impacts on biodiversity worldwide. In order to efficiently combat biodiversity loss and sustain the provision of ecosystem services, scientists as well as policy makers need to be able to predict species and species community responses to land-use trends. In the past different attempts both on large- and regional-scale have been made to investigate responses to land-use. Here we present a first comparison of model results between an African-wide meta-analytical framework and an independent field study.</p> <p>Africa has long been a focus of conservationists owing to its high spatial clustering of both biodiversity and human population leading to greater number of human-wildlife conflicts. Data on species- and community-level responses to a range of anthropogenic pressures from all over Africa were taken from the literature. Additional independent data on the diversity and abundance of African birds were collected during a two months field survey on the slopes of Mount Kilimanjaro and the Taita Hills. Both datasets are modeled and compared to see if similar conclusions are reached. The results advance our understanding of how well predictions of large-scale models are reflected in local biodiversity studies and vice versa.</p

Supplementary Material S1 from Synergistic impacts of habitat loss and fragmentation on model ecosystems

Habitat loss and fragmentation are major threats to biodiversity, yet separating their effects is challenging. We use a multi-trophic, trait-based and spatially explicit general ecosystem model to examine the independent and synergistic effects of these processes on ecosystem structure. We manipulated habitat by removing plant biomass in varying spatial extents, intensities and configurations. We found that emergent synergistic interactions of loss and fragmentation are major determinants of ecosystem response, including population declines and trophic pyramid shifts. Furthermore, trait-mediated interactions, such as a disproportionate sensitivity of large-sized organisms to fragmentation, produce significant effects in shaping responses. We also show that top-down regulation mitigates effects of land use on plant biomass loss, suggesting that models lacking these interactions—including most carbon stock models—may not adequately capture land-use change impacts. Our results have important implications for understanding ecosystem responses to environmental change, and assessing the impacts of habitat fragmentation

Correlation between distribution-based and CBC-based values of community composition metrics based on all traits together.

<p>Maps were generated of functional richness (FRICH; a) and functional divergence (FDIV; b, c). Functional divergence was measured using the Rao index. Observed values were calculated from recorded abundances at 68 evaluation Christmas Bird Count (CBC) sites. Distribution-based estimates of the metrics were generated using four methods, with the best two shown here, as in Fig. 3. Lines represent y = x. Full results for all four methods are presented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0044019#pone-0044019-t001" target="_blank">Table 1</a>.</p

The basic scheme for generating and evaluating maps of the trait composition of bird communities.

<p>The maps were generated by combining i) trait data, ii) refined distribution maps and iii) various types of abundance data. We used four estimates of abundance (a–d) for generating the maps, based on three basic assumptions about the abundance of bird species: 1) that all species have an equal abundance (of one) in all grid cells (black text); 2) that species differ in abundance from one another, but with no spatial variation in abundance within species (blue text); and 3) that abundance varies both among species and spatially (red text). The maps were evaluated using iv) trait data and v) local abundance data from the Christmas Bird Count sites. Note (*) that the abundance data from the CBC sites were divided into a set for generating the maps (2398 sites) and a set for evaluating the resulting maps (68 sites). Note also (†) that the same trait data were used for generating and evaluating the maps.</p

Correlation between distribution-based and CBC-based values of community composition metrics based on continuous traits.

<p>For each of the two continuous traits considered – body mass and generation length – maps were generated of community-weighted mean trait value (CWM; a, d, f, i), functional richness (FRICH; b, g) and functional divergence (FDIV; c, e, h, j). Observed values were calculated from recorded abundances at 68 Christmas Bird Count (CBC) evaluation sites. Distribution-based estimates of the metrics were generated using four methods, but only results from the best two methods are presented here: 1) overlaying range maps (black symbols); and 2) overlaying range maps with estimates of species abundance that vary among species and within species' ranges (red symbols). Abundance was estimated by modelling recorded abundances with respect to three environmental variables using generalized additive models. Lines represent y = x. Full results for all four methods are presented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0044019#pone-0044019-t001" target="_blank">Table 1</a>.</p

Correlation between distribution-based and CBC-based values of community composition metrics based on categorical traits.

<p>For each of the two categorical traits considered – migratory behaviour and diet – maps were generated of community-weighted mean trait value (CWM; a, d, f, i), functional richness (FRICH; b, g) and functional divergence (FDIV; c, e, h, j). For the categorical traits, community-weighted mean was calculated as the proportion of birds in each of the trait classes. Observed values were calculated from recorded abundances at 68 evaluation Christmas Bird Count (CBC) sites. Distribution-based estimates of the metrics were generated using four methods, with the best two shown here, as in Fig. 3. Lines represent y = x. Full results for all four methods are presented in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0044019#pone-0044019-t001" target="_blank">Table 1</a>.</p

Examples of maps of the trait-based metrics with values at the CBC sites overlaid.

<p>a) community-weighted mean value of (log-transformed) body mass; b) functional richness based on all four functional traits (body mass, generation length, migratory behaviour and diet) measured as the volume of a convex hull enclosing all species positions in trait space; and c) functional divergence measured using the Rao index. Colour schemes for the rasters and for the points are the same. Displayed using the Behrmann cylindrical equal-area projection.</p

Sites with Christmas Bird Counts between 2000 and 2009.

<p>Black crosses are sites used in the generation of trait maps (n = 2398), whereas white circles are sites used for evaluating the maps (n = 68). In Behrmann cylindrical equal-area projection.</p