RIQUEZA E DISTRIBUIÇÃO DE MACRÓFITAS AQUÁTICAS NO RIO GUARIBAS, PICOS, PIAUÍ

As macrófitas aquáticas desempenham importantes funções no ambiente aquático, contribuindo para a estruturação ambiental e para o equilíbrio biológico. O presente estudo teve como objetivo conhecer a riqueza biológica e a distribuição de macrófitas aquáticas no rio Guaribas, município de Picos, Piauí, corpo d’água do semiárido fortemente alterado por ações antrópicas. Para isso, amostras foram coletadas mensalmente em cinco estações no trecho urbano do referido rio, no período de setembro/2018 a fevereiro/2019. Para a coleta dos vegetais utilizou-se um quadrante com lados de 25 cm (0,0625 m2). O material foi conduzido para o Laboratório de Botânica da Universidade Federal do Piauí, campus de Picos, onde foi lavado, separado e identificado. Foram listadas 24 espécies distribuídas em 13 famílias botânicas, entre as quais foram mais representativas: Poaceae (5), Cyperaceae (3), Fabaceae (3), Araceae (2), Convolvulaceae (2) e Polygonaceae (2). As formas biológicas mais comuns foram as anfíbias e emergentes, anfíbias e as flutuantes livres. A maior riqueza florística ocorreu nos meses de fevereiro e setembro com 18 e 16 espécies, respectivamente. Conclui-se que a diversidade de macrófitas aquáticas do rio Guaribas sofreu influência dos fatores ambientais e antrópicos sendo favorecida pelo evento de chuvas, sucessão de espécies e eutrofização do corpo d’água.RICHNESS AND DISTRIBUTION OF AQUATIC MACROPHYTES SPECIES IN THE GUARIBAS RIVER, PICOS, PIAUÍ STATEABSTRACTAquatic macrophytes play important roles in the aquatic environment, contributing to environmental structuring and biological balance. The present study had as objective to know how environmental factors interfere in the biological richness and in the distribution of aquatic macrophytes in theGuaribas river, water body of the semiarid strongly altered by anthropic actions, municipality of Picos, Piauí. For that, samples were collected monthly in five stations in the urban section of the referred river, from September / 2018 to February / 2019. For the sampling of vegetables, a quadrant with sides of 25 cm (0.0625 m2) was used. The material was taken to the Botany Laboratory ofthe Federal University of Piauí, Picos campus, where it was washed, separated and identified. 24 species were listed, distributed in 13 botanical families, among which were most representative: Poaceae (5), Cyperaceae (3), Fabaceae (3), Araceae (2), Convolvulaceae (2) and Polygonaceae (2). The most common biological forms were amphibians and emergent, amphibious and free floating.The greatest floristic richness occurred in the months of February and September with 18 and 16 species, respectively. It is concluded that the diversity of aquatic macrophytes in the Guaribas River was influenced by environmental and anthropic factors, being favored by the event of rains, succession of species and eutrophication of the water body.

Mapping floristic diversity: a case study in Sicily

This paper presents an operational methodology to map and analyze the floristic richness of “target species” in Natura 2000 sites, making use of G.I.S. tools and procedures. A Floristic diversity map (scale 1:50,000), covering an area of 612 km2, was produced by a team of experts as part of the management plans of “Madonie Mountains” Sites of Community Importance (SCIs), located in Sicily (Italy). The primary grid map represents the richness of “target species”, which include species of Community interests, taxa on the National Red List, endemic and threatened, species protected under International Conventions, taxa of phytogeographic importance. Secondary data frames include a three-dimensional map representing the number of species present in each cell, a coarser species richness distribution (scale 1:400,000) and a reference map of endemism rate in the Mediterranean area. Such a cartographic document has proven to be an effective tool in biodiversity conservation planning. Furthermore, the knowledge of floristic richness and distribution is not only important for the management of protected areas, but it is also important for the sustainable management of cultural landscapes.

Weed flora analysis in El-Maadher agrosystem (Boussaada Oasis - Algeria)

The weed inventory in an arid land takes place to know and further control these plants. The study aims are to determine taxonomy, life form, chorology and to appreciate the weed harmfulness. A non-probabilistic sampling was conducted on five crops. We identified 41 species especially therophytes and mostly belong to the Mediterranean biogeographic element. The floristic richness by crop lets an average of 17 species and 24 for the richest. To assess the noxiousness, the partial indication of noxious obtains 21 potentially harmful weeds according to the frequencies. The numerical analysis of the data identified five groups. The weed noxiousness estimated by the abundance, frequency, and recovery, remains simple and efficient.

New records of mosses from the Dry Chaco forest of Santiago del Estero, Argentina

Background and aims: The bryophyte flora of Argentina is currently under study, nevertheless, there are still extensive areas unexplored, such as Santiago del Estero with only three records of bryophytes to the entire region. The aim of this work was to contribute to the knowledge of the moss flora of Santiago del Estero province, through the collection of samples in Copo National Park and surroundings. M&M: The specimens were collected in the Copo National Park and surroundings, processed and studied according to traditional techniques for bryophytes. Microscopic characters were observed with stereoscopic and light microscopy. A list of the species found is presented, with comments on the differentiating characters, habitat and distribution. Results: The following moss taxa were found to be new records for the province: Aloina rigida; Dimerodontium balansae; Didymodon umbrosus; Fabronia ciliaris; Macrocoma tenuis subsp. sullivantii; Pseudocrossidium arenicola; P. linearifolium; Stereophyllum radiculosum; Syntrichia chisosa, Trichostomum brachydontium and Venturiella glaziovii. The range of distribution of Tricherpodium beccarii is extended to the northeast of the province. Conclusions: Eleven species and one subspecies, distributed in ten genera and five families, are newly reported for the province of Santiago del Estero. The range of distribution of one species is extended to the northeast of the province. These first studies highlight the unexplored floristic richness of the region and its vulnerability due to the accelerated advance of the agricultural-livestock border.

Floristic Diversity in Secondary Forest under Munduruku Indigenous Agroextractivism

Aims: Knowledge is currently low about composition, richness and abundance of native plant species from secondary forests in traditional communities in the Tapajós River Basin, Western Amazon. These forests are of great importance to indigenous populations being niches of resistance to the advances of monocultures. The objective of this work was to evaluate the floristic composition of a secondary forest with typical indigenous extractive interventions. Study Design: The secondary forest studied located in indigenous Village. This forest had 15 years of natural regeneration and was therefore an anthropized forest, where the indigenous people removed wood, fibers, oils and fruits, thus characterizing the agroextractivism on this environment and a very particular floristic composition always in evolution. Place and Duration of Study: The research was in Santarem city, Pará state, in Ipaupixuna Village (02°32´46” S, 54°20'15” W) between June 2019 to December 2019. Methodology: The research had a descriptive approach for floristic study, but in the same time had a quantitative point of view with the use of regression analysis. The parameters evaluated were: 1. Species abundance, 2. Floristic Richness; 3. Plant diversity measured by the Jentsch Mixing Coefficient; 4. Relations between Circumference & Height of trees. The size of the sampled area was 1 (one) hectare of secondary forest. Results: A high abundance was found for Tapirira guianensis Aubl followed by Buchenavia huberi Ducke and Bellucia grossularioides (L.) Triana. Fabaceae was the family of greatest quantitative expression in this 15-year-old secondary forest in indigenous landscapes followed by Arecaceae. Conclusion: The secondary forest studied of 15 years of natural regeneration and random anthropogenic interventions by agroextractivists activities of Munduruku Indigenous people showed medium floristic richness and low floristic diversity. Interventions to enrich this secondary forest with plant species with high economic potential can bring environmental and economic benefits to these indigenous people.

Floristic and dispersion syndromes of Cerrado species in the Chapada do Araripe, Northeast of Brazil

Through this study, the objective was to contribute to the knowledge regarding floristic composition, classification and conservation status of the studied plant species as well as the dispersion syndromes of flora found in a disjoint Cerrado area ​in the Chapada do Araripe, Crato-CE. For the research development Rapid Survey method, applied in three walking lines (Line 1, Line 2 and Line 3) was adopted. Floriferous branches, fruits and seeds from species in the study area were collected in order to identify them and to characterize their diaspores, in view of fitting them into the corresponding dispersion syndromes. A total of 103 species were identified, the richest species taxa were: Fabaceae, Apocynaceae, Euphorbiaceae, Malpighiaceae and Myrtaceae. The most abundant species in the studied area were: Cordiera myrciifolia (“bola”) Miconia albicans (“Candeiro-de-pelo”), Caryocar coriaceum (pequi) and Copaifera langsdorffii (“pau d'oleo”). Three new occurrences were also recorded for the state of Ceará: Eriope tumidicaulis, Myrciaria cf. tenella and Stachytapheta cf. crassifolia. The most frequent dispersion syndrome was zoochoria, followed by anemocoria. Considering that most of the species occurring in the study area have their dispersion diaspores transported by a fauna element, the importance of these species for the maintenance of the observed floristic richness is evident.

Spatial scaling of pollen-based alpha and beta diversity within forest and open landscapes of Central Europe

Pollen is an abundant fossil and the most common proxy for plant diversity during the Holocene. Based on datasets in open, forest, and mixed habitats, we used the spatial distribution of floristic diversity to estimate the source area of pollen diversity and identify factors influencing the significance of this relationship.Our study areas are Bohemian-Moravian Highlands and White Carpathians (the Czech Republic and the Slovak Republic).Sampling 60 sites in forest and open habitats in two study regions with contrasting floristic diversity, we calculated taxonomic richness (alpha diversity) and total spatial variance (beta diversity) for pollen and floristic data along two transects, each 1 km long. Following this, we calculated the correlation between floristic and pollen diversity. We also assessed the consistency of the relationship in different habitats. Finally, we regressed local contributions of individual sites to the beta diversity of pollen and floristic data in each of the regions.There was a positive correlation between pollen and floristic richness in both habitats in both regions; open and mixed datasets were significant. The highest correlation (adjusted R2) mostly occurred within the first tens of metres (1.5–70) and then within the first hundreds of metres (250–550). Variances of pollen data significantly correlated with variances of floristic data between 100 and 250 m. Local contributions to beta diversity of pollen and plants significantly correlated in the forest and one of the mixed datasets.Floristic richness at the pollen site and position of the site within the landscape structure determine the sequence of the appearing species in the increasing distance. The number of species sets the source area of pollen richness and dissimilarity of appearing species controls the source area of pollen variance. These findings, linking pollen and floristic diversity, provide an essential stepping-stone for the reconstruction of historic plant diversity.

Why so different? A case study about Floras from a Mediterranean island

In light of the hypothesis that different authors, who have access to the same information and tools, can give different interpretations of the same reality, namely the vascular plants, existing within a determinate geographic boundary, this research aims to verify how and to what extent these differences can affect a checklist, and what critical issues and positive effects may arise in them. To this purpose, we compared two different checklists which were developed approximately in the same period for the same geographic area, the island of Sardinia (Italy). The results show that checklists of the same area can differ in quantitative terms, establishing a different value of floristic richness. Moreover, they can differ in qualitative terms due to the different approach adopted by the authors concerning nomenclature, taxonomy, and interpretation, delimitation, and circumscription of taxa. These discrepancies may have positive side effects as they offer insights for critical reviews and further investigation.

FLORISTIC RICHNESS AND DENSITY OF SALTMARSH COMMUNITIES DOMINATED BY TRIGLOCHIN MARITIMA L. (JUNCAGINACEAE) ON THE NORTHERN SEAS COASTS

The article presents the results of studying of the floral richness and density of communities dominated by the circumboreal temperate Arctic species Triglochin maritima L. (fam. Juncaginaceae). On the tidal zone of the western coast of the White sea in the direction from the lowland to the level of the low tide the geobotanical descriptions of plant communities on the model transects were made. The ecological characteristics of habitats, including geomorphic shore type, wave exposure and the mechanical composition of the substrate were given. It is revealed that various indicators of the geomorphological structure of the coast of the Bay effect on the characteristics and features of the floristic richness and density in the saltmarsh communities in these biotopes