The Carandilla Palm (Trithrinax schizophylla Drude, Arecaceae) is not extinct in Brazil: first primary records from the Chaco region of Mato Grosso do Sul

We report the occurrence of several remnant stands of Trithrinax schizophylla Drude in Porto Murtinho municipality, southwestern Mato Grosso do Sul state, Brazil. Until recently, the species was considered as probably extinct in the country. Trithrinax schizophylla is found only in the Chaco provinces of Argentina, Paraguay, and Bolivia, with a narrow strip in the southwestern region of Mato Grosso do Sul. The region is one of the most modified inside the Pantanal wetland in Brazil, and conservation actions are in need to protect this and other species in the region

Lauraceae no município de Corumbá, Mato Grosso do Sul, Brasil

Resumo O presente estudo teve por finalidade estudar as espécies da família Lauraceae no município de Corumbá-MS, baseado principalmente em coleções botânicas depositadas em herbários. Foram também realizadas coletas em várias regiões do município, principalmente na morraria Santa Cruz. São registradas para o município 10 espécies subordinadas a cinco gêneros, a saber: Aiouea trinervis, Aniba heringerii, Cassytha filiformis, Nectandra amazonum, N. cissiflora, N. gardneri, N. hihua, N. psammophila, Ocotea diospyrifolia e O. velloziana. Aniba heringerii é citada pela primeira vez para o Mato Grosso do Sul. Chaves para a identificação, descrições e ilustrações das espécies são apresentadas

Inundation and Fire Shape the Structure of Riparian Forests in the Pantanal, Brazil.

Inundation and fire can affect the structure of riparian vegetation in wetlands. Our aim was to verify if there are differences in richness, abundance, basal area, composition and topographic preference of woody species in riparian forests related to the fire history, flooding duration, or the interaction between both. The study was conducted in the riparian forests of the Paraguay River some of which were burned three times between 2001 and 2011. We sampled trees with a girth of at least 5 cm at breast height in 150 5 × 10 m plots (79 burned and 71 unburned). We also measured height of the flood mark and estimated the flooding duration of each plot. We performed Generalized Linear Mixed Models to verify differences in richness, basal area, and abundance of individuals associated to interaction of fire and inundation. We used an analysis of similarity (ANOSIM) and indicator species analysis to identify differences in composition of species and the association with burned and unburned area according to different levels of inundation. Finally, we used a hierarchical set of Generalized Linear Models (GLM), the so-called HOF models, to analyse each species' specific response to inundation based on topography and to determine their preferred optimal topographic position for both burned as well as unburned areas. Richness was positively associated with elevation only in burned areas while abundance was negatively influenced by inundation only in burned areas. Basal area was negatively associated with time of inundation independent of fire history. There were 15 species which were significant indicators for at least one combination of the studied factors. We found nine species in burned areas and 15 in unburned areas, with response curves in HOF models along the inundation gradient. From these, five species shifted their optimal position along the inundation gradient in burned areas. The interaction of fire and inundation did not appear to affect the basal area, but it did affect the richness, number of individuals, success of some species, and seemed to shape the boundary of these forests as shown by the difference in the positioning of these species along the inundation gradient

Relationship between the three dependent variables (richness, abundance and basal area) and the interaction of time of inundation and fire occurrence in riparian forests of the Paraguay River.

<p>Graphic performed with Generalized Linear Model only for visualization purposes once the results of GLM and GLMM were very similar. The continuous and dotted lines are burned and unburned areas respectively. The shaded areas in both lines are confidence intervals.</p

Maximum and minimum levels attained by Paraguay River (m) between 1974 and 2011 in relation to the zero of Ladário gauge, showing the study period (brace) and the years selected as the basis for the fire investigation (arrows).

<p>The dashed line indicates a general threshold for inundation of the Paraguay River.</p

Inundation and Fire Shape the Structure of Riparian Forests in the Pantanal, Brazil - Fig 6

<p><b>Species responses to the elevation gradient for (a) burned and (b) unburned areas.</b> Optima of the specific model types are depicted as symbols, while error bars indicate the tolerance range per species. Response model type IV (unimodal); V (unimodal left skewed); VI (unimodal right skewed) and VII (multimodal). Species names were abbreviated to eight letter codes. Elevation is relative to the Ladário gauge.</p

Levels of inundation of the Paraguay River between 2000 and 2013 (m) and monthly mean of rain (cm) in the municipalities of Corumbá and Ladário, MS, Brazil.

<p>Data provided by Brazilian Navy and INMET (Brazilian National Institute of Meteorology).</p

Results for the three GLMM models.

<p>Interactions were found to be significant for richness and abundance but not for basal area. The applied distribution type is listed beneath the name of the respective dependent variable. Numbers in brackets denote standard errors. Pseudo-R² calculation followed Nakagawa & Schielzeth [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0156825#pone.0156825.ref040" target="_blank">40</a>]. The marginal R² shows the variation explained only by the fixed effects while the conditional R² shows the variation of the fixed and random effects. For the negative-binomial abundance model calculation of R² was not possible hence we used the R² of a Poisson model as a proxy.</p

Indicator species analysis for all combinations of the fire regime and two inundation categories.

<p>Of the 24 combinations, 5 had species with significant group equalized indicator values (IndVal_g), and 13 of the 39 tree and shrub species were indicative for a factor combination. Low inundation refers to areas of 4.32–4.85 m, while high inundation refers to areas of 3.79–4.32 m in relation to the zero of the Ladário gauge.</p

Direct ordination of burned and unburned plots in the riparian forest of Paraguay River, showing the yearly mean time of inundation.

<p>Grey bars correspond to burned sites and black bars to unburned sites.</p