BIODIVERSITY OF TREES AND SHRUBS OF URBAN PLANTATIONS IN ARID REGIONS

Trees and shrubs are essential components in the production of ecosystem services. The aim of this study is to evaluate the biodiversity of plantations in arid regions. A floristic inventory was carried out in three biotopes using an exhaustive sampling approach. Diversity parameters were calculated to assess phytodiversity in each biotope. A total of 23 plants species belonging to 17 families, with a dominance of eudicots at 95.65% were recorded. The dominant families were Fabaceae (17.38%), Arecaceae, Lythraceae and Tamaricaceae (8.69%). The flora was mixed with 56.52% of exotic plant species. The most predominant plant species were Phoenix dactylifera L, Tamarix aphylla (L.) H. Karst, Dodonaea viscosa (L.) Jacq, and Leucaena leucocephala (Lam.) de Wit, these species accounted for 72.74% of all individuals inventoried. Shannon’s diversity index and Piélou index of evenness range from 2.68 to 2.95 bits and 0.64 to 0.69, respectively. Simpson’s index range from 0.78 to 0.82. Hamming distance range from 21 to 43. Plantations provide ecosystem services with great importance on ornamental interest. The data collected in this study should be used for creating a floristic database. This database will be regularly updated for monitoring urban plantations. The information resulting from the monitoring will help to improve the urban forest management projects in the development plan.

Distribution of endemic angiosperm species in Brazil on a municipality level

Herbarium collections and the data they hold are the main sources of plant biodiversity information. These collections contain taxonomical and spatial data on living and extinct species; consequently, they are the fundamental basis for temporal and spatial biogeographical studies of plants. Mega projects focused on providing digital and free access to accurate biodiversity data have transformed plant science research, mainly in the past two decades. In this sense, researchers today are overwhelmed by the many different datasets in online repositories. There are also several challenges involved in using these data for biogeographical analyses. Analyses performed on the data available in the repositories show that 70-75% of the total amount of data have spatial deficiencies and a high number of records lack coordinates. This shortage of reliable primary biogeographical information creates serious impediments for biogeographical analyses and conservation assessments and taxonomic revisions consequently produces obstacles for evaluations of threats to biodiversity at global, regional and local levels. With the aim of contributing to botanical and biogeographical research, this paper provides georeferenced spatial data for angiosperm species endemic to Brazil. The information from two reliable online databases, i.e. the Flora do Brasil 2020 floristic database (BFG) and Plantas do Brasil: Resgate Histórico e Herbário Virtual para o Conhecimento e Conservação da Flora Brasileira (REFLORA), which are both based on records collected over the course of the last two centuries, is used to create this spatial dataset. We provide three taxonomically-edited and georeferenced datasets for basal angiosperms, monocots and eudicots, covering a total of 14,992 endemic species from Brazil. Producing this consolidated dataset involved several months of detailed revision of coordinates and nomenclaturally updating of the names in these datasets. The information provided in this geo-referenced dataset, covering two centuries of specimen collections, will contribute to several botanical and mainly biogeographical studies.

Beyond forests in the Amazon: biogeography and floristic relationships of the Amazonian savannas

Open habitats such as grasslands occupy < 5% of the Amazon and are currently grouped under the broad term Amazonian savanna, covering an area of c. 267 000 km2, mostly in Brazil and Bolivia. These habitats are found isolated within an extensive rainforest matrix, having a distinct flora from the latter. The lower Amazon River is home to several patches of savanna that occupy both south and north banks of the river, in Santarém, Alenquer and Monte Alegre. Although having an abundance of herbaceous plants, most studies on these open areas focus only on tree species, ignoring the relevant non-woody component of the vegetation. Our objectives were to provide new surveys of seed plants for two Amazonian savanna sites and to take the opportunity to revisit the biogeographical links between Amazonian savanna, Amazonian canga vegetation and the central Brazilian cerrado (CBC) and caatinga, analysing woody and herbaceous plants. We created a floristic database that includes sites of Amazonian savannas, including campinarana, coastal scrub (restinga), CBC and Amazonian campos rupestres (on canga or other substrate). We compared those sites using multivariate analyses to find out the degree of floristic resemblance between sites. We prepared a new list of 406 species of seed plants [336 in Parque Estadual de Monte Alegre (PEMA) and 117 in Serra do Itauajuri (SI)], including 23 new records for the state of Pará and some putative new species for science. The Amazonian savannas form three loosely arranged groups, whereas the Amazonian canga formed a cohesive assemblage. Both groups were contrasted against cerrado and caatinga sites and had a distinctive flora from both. Sites from north-western Pará (Alter do Chão, PEMA and SI) were grouped with their northern counterparts in Roraima. An improved representation of the flora of these sites is provided, with more insight into the relationship between the Amazonian savanna sites and other vegetation types. It is worrying that recent changes of the Brazilian legislation place open environments, such as PEMA, in the path of vulnerability to disturbance and destruction.