scholarly journals Structure and Composition of Terra Firme and Seasonally Flooded Várzea Forests in the Western Brazilian Amazon

Forests ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1361
Author(s):  
Yennie K. Bredin ◽  
Joseph E. Hawes ◽  
Carlos A. Peres ◽  
Torbjørn Haugaasen

Research Highlights: Rare, or sparsely distributed, species drive the floristic diversity of upland, terra firme and seasonally flooded forests in the central Juruá—a remote and hitherto floristically poorly known area in the Brazilian Amazon. Background and Objectives: Floristic inventories are critical for modelling and understanding the role of Amazonian forests in climate regulation, for sustainable management of forest resources and efficient conservation planning. Yet, detailed information about the often complex spatial distributions of many Amazonian woody plants is limited. Here, we provide information about forest structure and species composition from a remote terra firme forest and an adjacent floodplain forest in the western Brazilian Amazon. More specifically, we ask (1) how floristically different are the terra firme and floodplain forests? and (2) how variable is species composition within the same forest type? Materials and Methods: Between September 2016 and October 2017, we inventoried 97 plots (each 0.1 ha; 100 × 10 m) placed at least 800 m apart, with 46 plots in terra firme forest and 51 in seasonally flooded forest. We included all trees, hemi-epiphytes and palms with diameter at breast height (dbh) > 10 cm and woody lianas > 5 cm dbh. We examine forest structure, family- and species-level floristic composition and species diversity within and between forest types using family and species importance values, rarefaction curves and dissimilarity matrices. Results: Terra firme forest and seasonally flooded forest woody plant communities differ both in structure and species composition, which was highly variable within forest types. Many species were shared between terra firme and seasonally flooded forests, but most species were forest type-specific. Whereas species richness was greatest in the terra firme forest, floodplain species richness was among the highest regionally. Conclusions: Floodplain forests are a crucial complement to terra firme forests in terms of Amazonian woody plant diversity.

Forests ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 942
Author(s):  
Isabela Freitas Oliveira ◽  
Fabricio Beggiato Baccaro ◽  
Fernanda P. Werneck ◽  
Thamara Zacca ◽  
Torbjørn Haugaasen

Amazonia comprises a mosaic of contrasting habitats, with wide environmental heterogeneity at local and regional scales. In central Amazonia, upland forest (terra firme) is the predominant forest type and seasonally flooded forests inundated by white- and black-water rivers (várzea and igapó, respectively) represent around 20% of the forested areas. In this work, we took advantage of a natural spatial arrangement of the main vegetation types in central Amazonia to investigate butterfly assemblage structure in terra firme, várzea and igapó forests at the local scale. We sampled in the low- and high-water seasons, combining active and passive sampling with traps placed in both the understory and canopy. Terra firme supported the highest number of butterfly species, whereas várzea forest provided the highest number of butterfly captures. The high species richness in terra firme may reflect that this forest type is floristically richer than várzea and igapó. Várzea is a very productive environment and may thus support a higher number of butterfly individuals than terra firme and igapó. Most butterfly species (80.2%) were unique to a single forest type and 17 can be considered forest type indicator species in this landscape. Floodplain forest environments are therefore an important complement to terra firme in terms of butterfly species richness and conservation in Amazonia.


2020 ◽  
Vol 67 (1) ◽  
Author(s):  
Sascha Buchholz ◽  
Volker Kelm ◽  
Simon J. Ghanem

AbstractNear-natural or semi-natural forests such as relatively undisturbed and old deciduous or mixed woodland are considered worth protecting and ecologically valuable habitats for bat conservation. In contrast, mono-specific forest plantations are considered ecologically less valuable; thus, decision-makers recommend these plantations as suitable locations for wind power stations and therefore want to further expand wind turbines in these habitats. This is expected to have a strong negative impact on the landscape because forests would be cleared for wind turbine pads and access roads and wind turbines rise above the trees with adverse impacts for bats. Therefore, we argue that, in light of bat conservation, the suitability of forest plantations for wind energy development is not, per se, warranted and that implications of wind power stations, even in mono-specific forest plantations, should be assessed and evaluated. We conducted long-term bat activity monitoring and recorded bat echolocation calls above the canopies of different forest sites (coniferous monoculture plantations and semi-natural mixed deciduous forests) in Germany and compared different forest types in terms of species richness, total bat activity, activity of the three bat species groups and species composition. Generalised linear models revealed that forest type and the amount of forest biotopes did not enhance bat activity. Ordination showed that species composition was not affected by forest type, location and connectivity. Mono-specific forest plantations can harbour a diverse bat fauna with high species activity and are, therefore, valuable bat habitats just as near-natural or semi-natural woodlands are. Environmental impact assessment and mitigation measures are vital in all forest types before and after planning for wind energy turbines. In particular, future planning and approval processes must consider the importance of mono-specific forest plantations for bat species protection.


2017 ◽  
Vol 47 (3) ◽  
pp. 237-246 ◽  
Author(s):  
Genimar Rebouças JULIÃO ◽  
Emmanuel Duarte ALMADA ◽  
Flávia Regina Capellotto COSTA ◽  
Marco Antônio Alves CARNEIRO ◽  
G. Wilson FERNANDES

ABSTRACT Topographic gradients in terra firme forests are associated with pronounced changes in soil texture, soil nutrients and distance to the water-table, thereby creating different hydric and nutritional conditions for plants and their associated herbivore community. The aim of this study was to investigate galling species and host plant richness and gall species composition across topographic habitats differing in nutrient and water stress in the Brazilian Amazon rainforest. Nineteen 250 x 3 m plots were randomly sampled in the valley, slope, plateau-slope transition, and plateau habitats in terra firme forests. All individual dicotyledonous plants 1 to 3 meters high were examined for the presence of insect galls. Galling species and host plant richness differed significantly among the studied habitats and were higher in slope habitats (drier habitats), as expected. More humid areas (valleys) showed the lowest richness of galling species, and a lower number of understory host plants. PERMANOVA and PERMDISP results demonstrated that the gall species composition differed significantly in the valley, slope, plateau-slope transition, and plateau areas. However, these structural differences in species composition could be due to unequal dispersion of variability among forest habitats. Our data suggested that spatial heterogeneity, such as a mosaic of local water status and nutrient availability resulting from the topographic conditions, can affect host plants and their associated galling insects.


2011 ◽  
Vol 39 (2) ◽  
pp. 97-110 ◽  
Author(s):  
PETER NEWTON ◽  
WHALDENER ENDO ◽  
CARLOS A. PERES

SUMMARYExtractive reserves account for a significant proportion of the remaining intact forest within Brazilian Amazonia. Managers of extractive reserves need to understand the livelihood strategies adopted by rural Amazonians in order to implement projects that benefit the livelihoods of local residents whilst maintaining forest integrity. Whilst resident populations are often descended from immigrant rubber-tappers, dynamic economic and social conditions have led to a recent diversification of land-use practices. This two-year study in two large contiguous extractive reserves encompassing both unflooded (terra firme) and seasonally flooded (várzea) forest, shows the degree to which local livelihood strategies of different settlements are heterogeneous. Extractive offtake of forest products and fish catches and agricultural activities, together with income from sales, for 82 households in 10 communities were quantified in detail by means of weekly surveys. The survey data were combined with interviews to examine the demographic and wealth profile, and engagement in alternative activities, in 181 households across 27 communities. All households and communities were engaged in all three subsistence activity types, but there was large variation in engagement with income-generating activities. Households within a community showed considerable congruence in their income-generating activity profiles, but there was significant variation between communities. Yields from agriculture and fishing were more temporally stable than extraction of highly-seasonal forest products. Generalized linear mixed models showed that forest type was consistently important in explaining yields of both agrarian and extractive products. Communities with greater access to terra firme forest were inherently more agricultural, and strongly committed to manioc production. Communities with greater access to flooded forest, however, showed a greater dependence on fishing. Conservation should be more attuned to the diversity and dynamism of livelihood strategies in protected areas; in particular, reserve managers and policy makers should account for the effect of local variation in physical geography when designing sustainable development projects.


Q'EUÑA ◽  
2019 ◽  
Vol 8 (1) ◽  
pp. 39-50
Author(s):  
Sufer Marcial Baez Quispe ◽  
Jorge Santiago Garate Quispe

Resumén Se presenta un análisis y comparación de la diversidad, estructura y composición florística de dos tipos de bosque (de tierra firme e inundable) en dos concesiones de conservación en la Zona de Amortiguamiento de la Reserva Nacional Tambopata (Madre de Dios, Perú). Se instalaron 2 parcelas de 10 m x 500 m (0,5 ha) por tipo de bosque, donde se inventarió todos los individuos con un diámetro a la altura del pecho (DAP) ≥ 10 cm. Se realizó la caracterización estructural de ambos tipos de bosque, se calculó la diversidad en ellos y se estudió la similitud entre ellos. Los resultados sugieren diferencias entre los dos tipos de bosque en términos de abundancia, dominancia, estructura y composición florística de acuerdo con otros estudios en la Amazonia. La diversidad de especies fue alta en el bosque de tierra firme (α-Fischer 84,4–57,4 y H' 4,0–4,5) y baja en el bosque inundable (α-Fischer 39.9 – 42.4, H' 3.3 – 3.4). Arecaceae fue la familia más importante en los bosques inundables, mientras que Moraceae fue la familia más importante en los bosques de tierra firme. Ficus gomelleira, Pterocarpus amazonum, Hevea guianensis, y Socratea exorrhiza fueron las especies más importantes en los bosques de tierra firme, mientras que Iriartea deltoidea, Otoba parvifolia y Pseudolmedia laevis, fueron las más importantes en los bosques inundables. La composición florística fue diferente entre los dos tipos de bosque, con 19,3 % de similitud en promedio (distancia de Bray-Curtis). Nuestros resultados coinciden con los obtenidos en otras investigaciones para la Amazonía Peruana. AbstractThe aim of this study was to compare and analyze the diversity, structure and floristic composition of two forest types at buffer zone of the Tambopata National Reserve (Madre de Dios). Two plots per forest types of 10 m x 500 m (0.5 ha) were used, where all individuals with a diameter at the breast height DBH ≥ 10 cm were inventoried. The total height (HT) and DBH of all tree individuals were measured. In the structural analysis, DBH size classes, density, dominance, and the importance index were calculated. We calculated the Shannon-Weaver index, α-Fischer index, and Bray-Curtis distance to evaluate the species diversity and similarity between the two forest types. The results suggest differences between forest types in terms of abundance, dominance, structure and floristic composition in agreement with other studies in the Amazonia. The species diversity is higher the terra firme forest (α-Fischer 84.4–57.4 y H' 4.0–4.5) than in the flooded forest (α-Fischer 39.9 – 42.4 y H' 3.3 – 3.4). The Arecaceae was the most important family in the flooded forest while the Moraceae was the most important family in terra firme forest. Ficus gomelleira, Pterocarpus amazonum, Hevea guianensis, and Socratea exorrhiza were the most important species in terra firme 


Author(s):  
Ana Carolina Antunes ◽  
Fabrício Baccaro ◽  
Victor Lery Caetano Andrade ◽  
José Ferreira Ramos ◽  
Roberto Da Silva Moreira ◽  
...  

Abstract In Amazonian igapó forests (seasonally flooded forests on blackwater river margins), the end of the annual flood pulse results in the formation of extensive mat-like seed patches. The seeds in these patches then germinate, forming a dense, highly heterogeneous, assemblage. Animal–plant interactions in these areas, as well as the influence that the patches have on the occurrence of herbivorous vertebrates, remain almost completely unstudied. Using camera traps in areas with and without seed/seedling patches, we tested the relationship between these seed accumulation sites and the presence of bird and mammal species. At the micro-scale (between treatments), vertebrate occurrence was not related to patch presence. At the larger scale (local), distance from adjacent upland (terra firme) forest and seed patch size were correlated with vertebrate distribution. The widespread occurrence of terrestrially active birds and mammals throughout igapó forests, not just where food resource densities were high, seems to be a compromise strategy between exploring the area to select the most favourable food items, and minimizing the risk of being predated when spending extended time foraging at the concentrated food sources represented by the seed patches. Our results underline the potential importance of igapó forests as a key habitat for a variety of terrestrial terra firme taxa, as well as emphasize the dynamic nature of this forest type, and should encourage further studies of this habitat and resource availability system.


2015 ◽  
Vol 5 (2) ◽  
pp. 261-270 ◽  
Author(s):  
Maria Cecilia Rosinski Lima Gomes ◽  
Edila Arnaud Ferreira Moura ◽  
João Paulo Borges Pedro ◽  
Maria Mercês Bezerra ◽  
Otacílio Soares Brito

Riverine populations that dwell in flooded forests (várzea) require suitable solutions for sanitation. An experimental project was started in 1998, using double-vault toilets in seasonally flooded houses in the Brazilian Amazon. The objective was to improve the health of inhabitants using adequate sanitation technology and health education. The focus of the present study was the assessment of that intervention. We compiled information from reports, local assessments, and interviews with users. In 2012, 14 years after the beginning of the project, 44% of the double-vault toilets were still in use. The main benefits noticed were awareness of the importance of toilets for reducing outdoor human waste and providing comfort, privacy, and safety for families. The sanitation project succeeded in reducing open defecation and raised the interest and demand for toilets. However, there is still a need for improving the construction of toilets and to better adapt them to flooded environments. We also include suggestions for improving the toilets and their use in flooded areas.


2015 ◽  
Vol 75 (3 suppl 1) ◽  
pp. 238-249 ◽  
Author(s):  
ACC. Pantoja ◽  
AL. Ilkiu-Borges ◽  
ACC. Tavares-Martins ◽  
ET. Garcia

Abstract Microclimatic conditions of tropical forest favour the high richness of bryophytes, which by being sensitive to environmental changes, are important indicators of habitat conditions. The aim of this study was to determine the richness and species composition of the bryophyte flora in fragments of terra firme forest on the great curve of the Xingu River, Pará state, Brazil. The collections were made in August and September 2012 in 14 fragments, in which were installed two plots per fragment, one at the edge and one inside, measuring 10 × 10 m each. The results showed 77 species in 45 genera and 18 families. Lejeunea setiloba Spruce and Marchesinia brachiata (Sw.) Schiffn. are new records for Pará state. The richness families in this study were the ones typically found in tropical forest surveys. A high richness of rare species in comparison to common ones, a pattern usually observed for plants in tropical forests was not reported in this study, probably due to historical fragmentation and disturbance in the area. The richness and species composition were determined mainly by the physiognomic characteristics of the studied forest fragments.


2014 ◽  
Vol 30 (5) ◽  
pp. 381-399 ◽  
Author(s):  
Joseph E. Hawes ◽  
Carlos A. Peres

Abstract:Constructing community fruit–frugivore networks has proved challenging in tropical forests to date, particularly in lowland Amazonia, which hosts the most diverse spectrum of frugivorous vertebrates and morphological fruit types worldwide. We assessed data on fruit resource production, frugivore assemblages and corresponding fruit–frugivore networks in two contrasting forest types along the Rio Juruá of western Brazilian Amazonia: seasonally flooded várzea (VZ) and unflooded terra firme forest (TF). Over 2 y we conducted monthly surveys of fruit patches and medium- to large-bodied vertebrate frugivores within three 100-ha plots (two TF, one VZ), supplemented by fruit surveys along 67 5-km transects distributed across two contiguous forest reserves (41 TF, 26 VZ). Observations of trophic interactions were supplemented by semi-structured interviews with experienced hunters and fishermen from 16 local communities. The resultant binary networks contained low proportions of all potential interactions (TF: 25.7%, VZ: 19.4%) between 36 functional groups of frugivores and 152 plant genera and, while we report significant heterogeneity in fruit resource use among broad frugivore guilds within each forest type, recursive partitioning analysis failed to clearly match differences in fruit selection to fruit traits. The annual flood pulse in várzea forests had an overriding influence on the species turnover of both fruit resources and frugivores between the two forest types, with higher-order effects on network structure.


Forests ◽  
2020 ◽  
Vol 11 (12) ◽  
pp. 1309
Author(s):  
Anderson Batista ◽  
Paula Gomides Vitor Scolforo ◽  
Henrique Ferraço Scolforo ◽  
José Marcio de Mello ◽  
Marcelino Guedes ◽  
...  

Modeling the growth of Bertholletia excelsa Bonpl. (B. excelsa) trees in natural forests is important for understanding the species’ ecology and for better defining site-specific management. In this sense, this study aimed to model the diameter growth rate of B. excelsa trees in contrasting forest environments in the Brazilian Amazon. This study was conducted in the Extractive Reserve Rio Cajari (RESEX Cajari). Growth models were fitted at species level to predict diameter growth rate in the two Amazonian forest environments. Subsequently, the age at which the B. excelsa tree in each forest environment reaches the minimum diameter for seed production was calculated by integrating the growth models. In each forest environment, the negative exponential behavior of the diametric growth rate of the tree species was fitted by an appropriate model. The time required for B. excelsa trees to reach the minimum diameter was shorter in the secondary forest environment when compared with that of the old growth terra firme forest (47 and 78 years to reach the diameter of 25 cm in the secondary and old growth terra firme forest, respectively). While the average growth pattern indicated higher diameter growth rates of B. excelsa in the secondary forest environment, the high level of uncertainty in the model’s estimation makes this inference complex. In conclusion, the secondary forest seems a favorable forest environment for the growth of B. excelsa trees, which may be an indicator of the potential for secondary forest environments to produce B. excelsa seeds in the future.


Sign in / Sign up

Export Citation Format

Share Document