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Revista de Biología Tropical, ISSN: 2215-2075, Vol. 69(2): 743-754, April-June 2021 (Published Jun. 21, 2021)

Phytosociology, successional level, and conservation

of the woody component in a “restinga” of Maranhão island, Brazil

Flávia Cristina Vieira Serra

Eduardo Bezerra Almeida Jr.

1. Programa de Pós-Graduação em Biodiversidade e Conservação, Universidade Federal do Maranhão, São Luís,

Maranhão, Brazil; flavia_biologia@hotmail.com

2. Departamento de Biologia, Universidade Federal do Maranhão, São Luís, Maranhão, Brazil; ebaj25@yahoo.com.br

(Correspondence*)

Received 11-VI-2020. Corrected 08-IV-2021. Accepted 11-VI-2021.

ABSTRACT

Introduction: The “restingas” (coast vegetation) can serve as a species corridor in ecotonal environments due

to the particulars regarding the composition of the flora. The studies covering the entire length of the Maranhão

state coast are necessary to understand the diversity and distribution of plant species present in the “restingas”.

Objective: The objective of this study was to characterize the structure and conservation of the woody vegeta-

tion of a “restinga” in Maranhão. Methods: Phytosociological sampling of woody vegetation was carried out

using the quadrants method, followed by classification of species by successional group; in addition to analyzing

the diametric and hypsometric data of the populations whose species presented the highest importance value

(IV). Results: In total, 24 species and 16 families were identified, 72 % of which were classified in the initial

stages of succession. The values of H’ and J’ were 2.637 nat.ind

-1

and 0.830, respectively. The mean height

and diameter were 2.1 m and 27.66 cm, respectively. The species Coccoloba ramosissima Wedd., Byrsonima

crassifolia (L.) Kunth, Anacardium occidentale L., Manilkara triflora (Allemão) Monach, and Astrocaryum

vulgare Mart. presented the highest IVs. Conclusions: It was observed that characteristics such as size, power

of regrowth, and ease of regeneration processes could be useful for choosing target species for recovery actions

in coastal areas.

Key words: phytosociology; diametric structure; vertical distribution; Maranhão state; environmental

restoration.

Vieira Serra, F.C., & Bezerra Almeida, E. Jr. (2021).

Phytosociology, successional level, and conservation of

the woody component in a “restinga” of Maranhão island,

Brazil. Revista de Biología Tropical, 69(2), 743-754.

https://doi.org/10.15517/rbt.v69i2.42265

The restinga has a high environmental rel-

evance in view of the vegetal and physiognom-

ic mosaic, its conservation is essential due to

the intense threat caused by anthropic actions

(Dias & Soares, 2008). In the Northeast region

of Brazil, despite the increase in research for

this ecosystem, as in States of the Bahia: Mene-

zes, Santana, Silva, Silva and Araújo (2012),

Santos, Zickel and Almeida Jr. (2015); Pernam-

buco: Almeida Jr., Santos-Filho, Araújo and

Zickel (2011), Cantarelli, Almeida Jr., Santos-

Filho and Zickel (2012a); Alagoas: Medeiros,

Santos-Filho, Almeida Jr., Pimentel and Zickel

(2010); Rio Grande do Norte: Almeida Jr.

and Zickel (2012), Medeiros, Almeida Jr.,

Abreu, Santos-Filho and Zickel (2014); Piauí:

Santos-Filho, Almeida Jr. and Zickel (2013a);

Paraíba: Vicente, Almeida Jr., Santos-Filho

and Zickel (2014); Sergipe: Santana, Rocha,

Oliveira, Prata and Ribeiro (2020) - the existing

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Revista de Biología Tropical, ISSN: 2215-2075 Vol. 69(2): 743-754, April-June 2021 (Published Jun. 21, 2021)

knowledge about wealth and diversity still

does not correspond to the coastal territorial

extension of the region. What makes broader

analysis impossible due to the particulari-

ties in various aspects of its biodiversity and

conservation status.

Considering, in particular the Maranhão

coastline, the knowledge about restinga vegeta-

tion is still restricted to a few floristic studies

(Cabral-Freire & Monteiro, 1993; Serra, Lima,

& Almeida Jr., 2016; Silva, Araujo, & Almeida

Jr., 2016a; Amorim, Amorim, & Almeida Jr.,

2016a; Lima & Almeida Jr., 2018) and phyto-

sociological records (Araujo, Silva, & Almeida

Jr., 2016; Amorim, Santos-Filho, & Almeida

Jr., 2016b; Machado & Almeida Jr., 2019;

Almeida Jr., Correia, & Santos-Filho, 2020).

These studies represent only a small part of the

coast in Maranhão, which is in turn in a large

transition area between vegetation in the Ama-

zon and Cerrado domain (Silva et al., 2016b).

Knowing that restingas can serve as a spe-

cies corridor in ecotonal environments, studies

covering the entire length of the Maranhão

coast are necessary to understand the diversity

and distribution of plant species present in the

restingas (Castro, Moro, & Menezes, 2012;

Serra, Lima, & Almeida Jr., 2016).

One of the ways to obtain information

about plant species for conservation is related

to knowledge of the structure of the plant

community (Nadkarni, Mcintosh, & Cushing,

2008). Thus, height and diameter measure-

ments could provide data on the plant com-

munity or be used for the analysis of one or

more species of interest in the succession

processes. The existence of different strata in

the plant community enables greater diver-

sity of micro-habitats, which can increase the

diversity of species and ecological interactions

(Souza, Souza, Gama, & Leite, 2003). There-

fore, vertical stratification could contribute as

an indicator of environmental sustainability

of a forest, influencing wealth, diversity, and

biomass production (Souza et al., 2003) among

other factors.

Therefore, evaluation of conditions regard-

ing the dynamics of the forest can generate

subsidies for future forest management actions

based on indications about the populations

in the development of the plant community

(Siminski, Mantovani, dos Reis & Fantini,

2004). Considering the need for data related

to the structure of the woody vegetation of

the restingas in Maranhão (Serra et al., 2016;

Machado & Almeida Jr., 2019; Almeida Jr. et

al., 2020), the current study aims to character-

ize the structure of woody vegetation, analyze

the diametric and hypsometric distribution of

species of greatest ecological importance, and

indicate the level of succession to support

future research on recovery and or management

of coastal areas.

MATERIALS AND METHODS

Study area: The collections were carried

out in a restinga in the Eastern part of Maranhão

Island (02º38’47.85’’ S & 44º09’05.76’’ W), on

the Sítio Aguahy. The area is owned by Com-

panhia Farmacêutica Quercegen Agronegócios

I Ltda., in the municipality of São José de Rib-

amar, Maranhão state (Fig. 1).

The Sítio Aguahy has an area of 400 ha

consisting of a transition between fragments

of regenerating Amazon forest, mangrove, and

restinga (Serra et al., 2016; Marinho, Muniz,

& Azevedo, 2018). The fragment denominated

restinga occupies an area of approximately 50

ha, consisting of vegetation from herbaceous

to arboreal stratum, presenting physiognomies

of floodable fields, non-floodable shrubby,

and non-floodable forest (Serra et al., 2016)

(Fig. 2). The climate of the region, according

to the classification of Köppen (1948), is of the

Aw type, having two distinct seasons: a rainy

season that extends from January to June and

a dry season that begins in July and extends

until December. The average rainfall index of

Maranhão Island is approximately 2 000 mm/

year and the average temperatures through-

out the year vary between 25.5 and 28.6 °C

(INMET, 2016).

Vegetation sampling: Phytosociological

sampling was carried out in 2015 and followed

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Revista de Biología Tropical, ISSN: 2215-2075, Vol. 69(2): 743-754, April-June 2021 (Published Jun. 21, 2021)

the quadrants method (Cottam & Curtis, 1956).

In each quadrant, the individual closest to the

central point that meets the inclusion criteria of

the sample is marked and identified. Then its

distance from the central point of the quadrant

is recorded (Durigan, 2003). Five transections

were plotted on area, arranged in parallel, each

measuring 100 m. Ten points were allocated

to each transection, with a distance of 10 m

between each point, totaling 50 points. Indi-

viduals woody with a diameter at ground height

(DGH) ≥ 3 cm were measured. In the case of

tillered individuals (plants that had branches at

the base of the stem) all the trunks were mea-

sured and the sum of the perimeters of each

tiller was used to represent the final value of

the plant diameter.

This sample size has been considered

satisfactory for restinga areas, achieving

sample sufficiency through stability in the

species saturation curve (Zickel et al., 2015).

In addition, this sampling method follows the

studies carried out for the woody strata of

the Northeast region (Medeiros et al., 2010;

Almeida Jr. & Zickel, 2012; Santos-Filho et

al., 2013a; Medeiros et al., 2014; Machado &

Almeida Jr., 2019).

For the analysis of the community organi-

zation, relative density (RD), relative frequen-

cy (RF), basal area (BA), relative dominance

(RDO), importance value (IV), Shannon diver-

sity index (H’), Pielou equability index (J’),

and total wealth (S) were calculated using the

FITOPAC 2.0 package (Shepherd, 2009).

For the analysis of the diametric distribu-

tion, a histogram was elaborated with the num-

ber of individuals per class of diameter (10 cm

interval), representing the plant community. To

Fig. 1. Location of Ilha do Maranhão, where the restinga of Sítio Aguahy is located, municipality of São José de Ribamar,

Maranhão state. Source D. Muniz.