Anthropogenic disturbances stimulate natural regeneration of Euxylophora paraensis Huber in a forest fragment in the eastern Amazon

In the Brazilian Amazon, forest fragments increase annually leading many species to local extinction. Euxylophora paraensis Huber is an endemic species whose natural habitat is restricted to the north of Brazil. The natural regeneration was evaluated using 10 circular plots of land each with a radius of 20 meters. The density of regenerating individuals at the edge and the interior of the fragment and the behavior in relation to the parent tree. The Periodic Annual Increment of the diameter and the height were calculated individually for each plant that remained alive during all four measurements and GLM (General Linear Model) was applied to verify if there were differences between environments and the size of the individuals. The results show that the density of natural regeneration increases as the distance from the parent tree increases and has a significant negative correlation with canopy area, the smaller the canopy area the higher the density of individuals. Larger diametric growth was observed in saplings and small trees at the edge and larger increments of height in small trees were observed both at the edge and interior of the fragments. Therefore, natural regeneration is influenced by the process of forest fragmentation where the germination of seeds and establishment of saplings is favorable, however, there were no adult trees at the edge.

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Small mammal glucocorticoid concentrations vary with forest fragment size, trap type, and mammal taxa in the Interior Atlantic Forest

Scientific Reports ◽

10.1038/s41598-021-81073-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Sarah A. Boyle ◽

Noé U. de la Sancha ◽

Pastor Pérez ◽

David Kabelik

Keyword(s):

Atlantic Forest ◽

Small Mammals ◽

Acute Stress ◽

Physiological Stress ◽

Fragment Size ◽

Hair Shaft ◽

Forest Fragments ◽

Forest Fragment ◽

Trapping Methods ◽

Free Ranging

AbstractSpecies that live in degraded habitats often show signs of physiological stress. Glucocorticoid hormones (e.g., corticosterone and cortisol) are often assessed as a proxy of the extent of physiological stress an animal has experienced. Our goal was to quantify glucocorticoids in free-ranging small mammals in fragments of Interior Atlantic Forest. We extracted glucocorticoids from fur samples of 106 small mammals (rodent genera Akodon and Oligoryzomys, and marsupial genera Gracilinanus and Marmosa) from six forest fragments (2–1200 ha) in the Reserva Natural Tapytá, Caazapá Department, Paraguay. To our knowledge, this is the first publication of corticosterone and cortisol levels for three of the four sampled genera (Akodon, Oligoryzomys, and Marmosa) in this forest system. We discovered three notable results. First, as predicted, glucocorticoid levels were higher in individuals living withing small forest fragments. Second, animals captured live using restraint trapping methods (Sherman traps) had higher glucocorticoid levels than those animals captured using kill traps (Victor traps), suggesting that hair glucocorticoid measures can reflect acute stress levels in addition to long-term glucocorticoid incorporation. These acute levels are likely due to urinary steroids diffusing into the hair shaft. This finding raises a concern about the use of certain trapping techniques in association with fur hormone analysis. Finally, as expected, we also detected genus-specific differences in glucocorticoid levels, as well as cortisol/corticosterone ratios.

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Distribution of Atta (Hymenoptera - Formicidae) in "terra-firme" rain forest of Central Amazonia: density, species composition and preliminary results on effects of forest fragmentation

Acta Amazonica ◽

10.1590/1809-43921988183315 ◽

1988 ◽

Vol 18 (3-4) ◽

pp. 309-315 ◽

Cited By ~ 14

Author(s):

Heraldo Luís de Vasconcelos

Keyword(s):

Species Composition ◽

Rain Forest ◽

Abundant Species ◽

Forest Fragments ◽

Forest Fragment ◽

Terra Firme ◽

Atta Sexdens ◽

Conservation Areas ◽

Continuous Forest ◽

Leaf Cutting

One hundred and fourteen hectares of a "terra-fiirme" rain forest 70 km north of Manaus, Amazonas, Brazil, were surveyed for leaf-cutting ant colonies (Atta spp). One half of this area was in isolated forest fragments (surrounded by pastures or second growth) of two sizes: 1 and 10 ha. The other half was in non-isolated fragments (connected to a large parch of forest) of the same sizes. Only two species occured in this forest: Atta sexdens sexdens L. and A. cepfhalotes L. The first was the most abundant species with a mean density of 0.35 colonies per ha. The mean density of A. cephalotes colonies was 0.03 per ha. The density of colonies was not significantly different between the isolated fragments and the continuous forest. Furthermore, the species composition did not change with isolation. However, pre-isolation data and long term monitoring are necessary to conclude that the isolation of a forest fragment has no effect upon Atta colonies. The non-uniform spatial distribution of Atta colonics within the "terra-firme" forest must be taken into account when selecting conservation areas in the Amazon, in order to preserve this important group of ants together with their native habitat.

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Characteristics and factors influencing the natural regeneration of Larix principis-rupprechtii seedlings in northern China

PeerJ ◽

10.7717/peerj.12327 ◽

2021 ◽

Vol 9 ◽

pp. e12327

Author(s):

Weiwen Zhao ◽

Wenjun Liang ◽

Youzhi Han ◽

Xi Wei

Keyword(s):

Spatial Distribution ◽

Natural Regeneration ◽

Pair Correlation ◽

Principal Component ◽

Northern China ◽

Point Pattern Analysis ◽

Point Pattern ◽

Adult Trees ◽

Herb Diversity ◽

Univariate Distribution

Larix principis-rupprechtii is an important and widely distributed species in the mountains of northern China. However, it has inefficient natural regeneration in many stands and difficulty recruiting seedlings and saplings. In this study, we selected six plots with improved naturally-regenerated L. principis-rupprechtii seedlings. A point pattern analysis (pair-correlation function) was applied to identify the spatial distribution pattern and correlation between adult trees and regenerated seedlings mapped through X/Y coordinates. Several possible influencing factors of L. principis-rupprechtii seedlings’ natural regeneration were also investigated. The results showed that the spatial distribution patterns of Larix principis-rupprechtii seedlings were concentrated 0–5 m around adult trees when considering the main univariate distribution type of regeneration. There was a positive correlation at a scale of 1.5–4 m between seedlings and adult trees according to bivariate analyses. When the scale was increased, these relationships were no longer significant. Generally, adult trees raised regenerated L. principis-rupprechtii seedlings at a scale of 1.5–4 m. Principal component analysis showed that the understory herb diversity and litter layer had a negative correlation with the number of regenerated seedlings. There was also a weak relationship between regenerated numbers and canopy density. This study demonstrated that the main factors promoting natural regeneration were litter thickness, herb diversity, and the distance between adult trees and regenerated seedlings. Additionally, these findings will provide a basis for the late-stage and practical management of natural regeneration in northern China’s mountain ranges.

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ESTRUTURA, DIVERSIDADE E HETEROGENEIDADE DO ESTRATO REGENERANTE EM UM FRAGMENTO FLORESTAL URBANO APÓS 10 ANOS DE SUCESSÃO FLORESTAL

FLORESTA ◽

10.5380/rf.v45i3.34533 ◽

2015 ◽

Vol 45 (3) ◽

pp. 535 ◽

Cited By ~ 1

Author(s):

Raphaela Vilela Eiras e Paiva ◽

José Hugo Campos Ribeiro ◽

Fabricio Alvim Carvalho

Keyword(s):

Multivariate Analysis ◽

Species Diversity ◽

Urban Forest ◽

Shannon Index ◽

Forest Fragments ◽

Ecological Groups ◽

Small Fragment ◽

Forest Fragment ◽

Semideciduous Forest ◽

Dalbergia Nigra

Este estudo visou avaliar a composição florística, a fitossociologia e a diversidade de espécies do estrato regenerante arbóreo de um pequeno fragmento (0,5 ha) de Floresta Estacional Semidecidual, após 10 anos de abandono, no perímetro urbano do município de Juiz de Fora, MG, Brasil. Os indivíduos da regeneração arbórea (altura ≥ 1 m e DAP < 5 cm) foram amostrados em 25 parcelas aleatórias de 5 x 5 m. Foram amostrados 1224 indivíduos pertencentes a 40 espécies. Houve uma forte predominância (> 90%) de espécies de estágios sucessionais iniciais (pioneiras e secundárias iniciais). Como reflexo da forte dominância ecológica observada, exercida principalmente pela elevada densidade das espécies Dalbergia nigra e Siparuna guianensis, o valor do índice de diversidade de espécies de Shannon (H’ = 2,38) foi muito inferior aos valores encontrados para fragmentos florestais maduros. Mesmo sendo um fragmento pequeno, isolado e em estágio inicial de sucessão secundária, análises multivariadas (agrupamento e DCA) evidenciaram a formação de grupos florísticos e uma forte diferenciação no arranjo das espécies, evidenciando a heterogeneidade típica de florestas tropicais. Embora apresente uma baixa diversidade, esse fragmento urbano tem funções ecológicas e sociais importantes para a região, que carece de áreas verdes para a conservação da flora nativa.AbstractStructure, diversity and heterogeneity of regeneration stratum in an urban forest fragment after 10 years of forest succession. This research aimed to evaluate the floristic composition, phytosociology and species diversity of the regenerating woody stratum of a small fragment (0.5 ha) of Semideciduous Forest, after 10 years of abandonment, in the municipality of Juiz de Fora, MG, Brazil. All woody individuals (height ≥ 1 m dbh <5 cm) were sampled at 25 random plots of 5 x 5 m. We sampled 1224 individuals belonging to 40 species. There was a strong predominance (> 90%) of species of early successional stages (pioneer and early secondary). Reflecting the strong observed ecological dominance, exercised primarily by the high density of the species Dalbergia nigra and Siparuna guianensis, species diversity value (Shannon index H '= 2.38) was much lower than the values found for mature forest fragments in this region. Although a small fragment, isolated and in early stages of secondary succession, the multivariate analysis (cluster and DCA) revealed the formation of distinct floristic groups and a strong differentiation in the arrangement of the species, showing the tropical forests typical heterogeneity. Although it has a low diversity, this urban fragment has ecological and social importance to the region, that present lack of green areas to conserve the native flora.Keywords: Phytosociology; multivariate analysis; gradient analysis; ecological groups.

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ORGANIC MATTER IN AREAS UNDER SECONDARY FORESTS AND PASTURE

CERNE ◽

10.1590/01047760201723032333 ◽

2017 ◽

Vol 23 (3) ◽

pp. 283-290

Author(s):

Carlos Eduardo Gabriel Menezes ◽

Roni Fernandes Guareschi ◽

Marcos Gervasio Pereira ◽

Lúcia Helena Cunha Anjos ◽

Maria Elizabeth Fernandes Correia ◽

...

Keyword(s):

Organic Matter ◽

Soil Carbon ◽

Carbon Stock ◽

Secondary Forest ◽

Intermediate Stage ◽

C3 Plants ◽

Secondary Forests ◽

Forest Fragments ◽

Forest Fragment ◽

Soil Carbon Stock

ABSTRACT The objective of this study was to evaluate the soil carbon stock (Stock C) and bulk density, the chemical and granulometric fractions of the organic matter and the isotopic signal of the soil δ13C in forest fragments and a mixed managed pasture (MMP). The study was carried out in the municipality of Pinheiral, State of Rio de Janeiro. The evaluated areas were: fragment of secondary forest in initial stage (SFIS) with 20 years of regeneration; fragment of secondary forest in intermediate stage (SFINS), with 25 years of regeneration; advanced secondary forest fragment (SFAS) with 60 years of regeneration and mixed pasture managed (MHP). The attributes related to soil carbon showed significant responses to the effects of land degradation / recovery processes, especially for the following indicators: total organic carbon, organic matter stock and particulate organic matter. No significant alterations for humic substances, and prevalence of the humin fraction was found. The most significant changes in δ13C values occurred up to the depth of 60 cm. In the grassland area, at 0-10 cm, 67% of the carbon stock comes from C4 plants, reducing in the subsequent layers. In SFINS and SFAS areas, at 0-10 cm, the contribution of C3 plants was significant, with minor changes in depth.

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Limited natural regeneration of unique Scalesia forest following invasive plant removal in Galapagos

PLoS ONE ◽

10.1371/journal.pone.0258467 ◽

2021 ◽

Vol 16 (10) ◽

pp. e0258467

Author(s):

Anna Walentowitz ◽

Michael Manthey ◽

María Belén Bentet Preciado ◽

Rafael Chango ◽

Christian Sevilla ◽

...

Keyword(s):

Plant Species ◽

Natural Regeneration ◽

Large Scale ◽

Invasive Plant ◽

Linear Models ◽

Light Availability ◽

Percent Cover ◽

Introduced Plants ◽

Adult Trees ◽

Sapling Survival

More than 60% of the flora of the Galapagos Islands is introduced and some of these species have become invasive, severely altering ecosystems. An example of an affected ecosystem is the Scalesia forest, originally dominated by the endemic giant daisy tree Scalesia pedunculata (Asteraceae). The remnant patches of this unique forest are increasingly being invaded by introduced plants, mainly by Rubus niveus (blackberry, Rosaceae). To help large-scale restoration of this ecologically important forest, we seek to better understand the natural regeneration of S. pedunculata after invasive plant control. We monitored naturally recruited S. pedunculata saplings and young trees over five years in an area where invasive plant species are continuously being removed by manual means. We measured survival, height and growth of S. pedunculata saplings and young trees along permanent transects. Percent cover of surrounding plant species and of canopy shade directly above each S. pedunculata individual were determined, as well as distance to the next mature S. pedunculata tree. We identified potential factors influencing initial sapling survival and growth by applying generalized linear models. Results showed a rapid growth of saplings and young trees of up to 0.45 cm per day and a high mortality rate, as is typical for pioneer species like S. pedunculata. Sapling survival, growth and mortality seemed to be influenced by light availability, surrounding vegetation and distance to the next adult S. pedunculata tree. We concluded that natural regeneration of S. pedunculata was high only five months after the last herbicide application but that 95% of these recruits had died over the 5-year period. Further studies are needed to corroborate whether the number of surviving trees is sufficient to replace the aging adult trees and this way maintain remnants of the Scalesia forest. Urgent action is needed to help improve future restoration strategies to prevent further degradation of this rapidly shrinking threatened forest ecosystem.

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Floristic Composition and Community Structure of Epiphytic Angiosperms in an Urban Forest Fragment in the Eastern Amazon

Research in Ecology ◽

10.30564/re.v3i4.3830 ◽

2021 ◽

Vol 3 (4) ◽

Author(s):

Josélia Rozanny Vieira Pacheco ◽

Felipe Fajardo Villela Antolin Barberena

Keyword(s):

Community Structure ◽

Urban Forest ◽

Diversity Index ◽

Species Conservation ◽

Floristic Composition ◽

Neotropical Region ◽

Forest Fragments ◽

Forest Fragment ◽

Importance Value ◽

Vascular Epiphytes

Vascular epiphytes are one of the most important forest components, contributing to microclimatic maintenance. These plants find ideal conditions for development in the Amazon due to the spatial heterogeneity and high temperature and humidity typical of this biome. In recent years, the Brazilian Amazon has undergone dramatic changes in its landscape, mainly due to the increase in deforestation and fire rates. We present here the floristic composition and analyze the community structure of epiphytic angiosperms of an urban forest fragment in Eastern Amazon. A total of 71 epiphytic individuals were recorded belonging to eight species and four families. Orchidaceae was the most representative family, corroborating the pattern for surveys of epiphytic diversity in the Neotropical region. Epiphytic species were found on 24 individuals of 10 tree species. The epiphytic importance value (IVe) was low for all species, except for Aechmea tocantina and Rhipsalis baccifera. Cactaceae was the family with the highest IVe. Most epiphytes were found in the crown of trees (83.1%). The diversity index of the fragment was H’ = 1.80 and the equity index was J= 0.87, reflecting the absence of highly dominant species. Conservation of urban forest fragments is necessary for the maintenance of epiphytic flora and ecosystem services.

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Abundância e Diversidade de Coleópteros de Solo em Fragmentos de Capoeira ao Entorno da Zona Urbana do Município de Uruará-PA, Brasil.

EntomoBrasilis ◽

10.12741/ebrasilis.v8i1.414 ◽

2015 ◽

Vol 8 (1) ◽

pp. 30-37 ◽

Cited By ~ 3

Author(s):

Reinaldo Lucas Cajaiba ◽

Wully Barreto Da Silva

Keyword(s):

Soil Fauna ◽

Diversity Index ◽

Human Action ◽

Forest Fragments ◽

Forest Fragment ◽

Species Accumulation Curves ◽

Accumulation Curves ◽

Abundance And Diversity ◽

The Impact

A ação humana vem transformando as paisagens florestais em fragmentos isolados de remanescentes, podendo levar muitas espécies à extinção. Desta maneira se faz necessário a realização de estudos para o conhecimento e adequada caracterização da fauna de solo e, por conseguinte sua preservação. O objetivo do presente trabalho foi caracterizar a fauna de coleópteros em um fragmento florestal ao entorno da cidade de Uruará, PA. Para tanto, utilizou-se armadilhas tipo pitfall não iscadas para a coleta. O fragmento foi dividido em quatro transectos, com armadilhas instaladas ao longo da borda (T1), 50 m (T2), 100 m (T3) e 200 m (T4). Foram coletados 196 indivíduos, classificados em sete famílias e 34 espécies/morfoespécies. A família que apresentou a maior abundância foi a Curculionidae representando 56,40% da abundância, tendo o gênero Xyleborus sp. a maior dominância. Através do índice de Diversidade de Shanon, observou-se que a área de borda apresentou a menor diversidade e maior dominância (índice de Berger-Parker). Através da curva de acumulação e dos estimadores de espécies, ficou evidenciado que a área de estudo apresenta uma quantidade superior de espécies ao encontrado no presente estudo, e que pesquisas futuras são necessárias para um melhor acompanhamento das alterações que ocorrem nos fragmentos florestais com a finalidade de propor medidas de menor impacto e preservação dessa biodiversidade. Abundance and Diversity of Ground Dwelling Beetles (Arthropoda: Insecta) in Fragments of Shrubbery Vegetation (Capoeira) in the Surroundings of the Urban Zone of Uruará City-PA, Brazil Abstract. Human action has been transforming forest landscapes into isolated fragments, which may lead to the extinction of many species. Therefore, studies should be conducted to provide knowledge and the appropriate characterization of soil fauna, and, consequently, its preservation. This study was aimed to characterize the fauna of beetles in a forest fragment in the surroundings of Uruará city, PA. Unbaited pitfall traps were used for the collection of the beetles. The fragment was divided into four transects, with traps installed along the border (T1), 50 m (T2), 100 m (T3) and 200 m (T4). 196 individuals classified in seven families and 34 species/morphospecies were collected. The most abundant family was the Curculionidae accounting for 56.40% of the abundance, with gender Xyleborus sp. being the most dominant. Measurement with the Shannon Diversity Index for measurement showed lower diversity and greater dominance (Berger-Parker index) in the border area. Using species accumulation curves and estimators it became evident that the study area had a greater number of species than those found in the present study, and that further studies are needed to better monitor changes in forest fragments in order to propose measures to reduce the impact on this biodiversity and preserve it.

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Diversidade de Carabidae (Coleoptera) Amostrados em Áreas de Reflorestamento de Mata Ciliar e Fragmento Florestal, no Estado do Paraná

EntomoBrasilis ◽

10.12741/ebrasilis.v5i3.255 ◽

2012 ◽

Vol 5 (3) ◽

pp. 217-222

Author(s):

Tamara Quinteiro ◽

José Lopes ◽

Ivan Carlos Fernandes Martins

Keyword(s):

Riparian Vegetation ◽

The State ◽

Forest Fragments ◽

Pitfall Traps ◽

Forest Fragment ◽

Eating Habit ◽

Biodiversity Indicator ◽

Baited Traps ◽

Collection Number ◽

Significant Difference

Carabidae são Coleoptera com a maioria de suas espécies apresentando hábito alimentar predatório. O objetivo do presente trabalho foi estudar a diversidade e abundância da família Carabidae (Coleoptera) em áreas de fragmento florestal e em áreas de reflorestamento de mata ciliar, evidenciando a importância deste grupo como indicador da biodiversidade em relação ao sucesso do reflorestamento. Os besouros foram amostrados por meio de armadilhas de solo pitfall, em fragmentos florestais e reflorestamentos de mata ciliar em três municípios do estado do Paraná. A abundância de Carabidae foi maior nos reflorestamentos de mata ciliar. A espécie Odontochila nodicornis (Dejean) foi, significativamente, a mais abundante e encontrada em todas as áreas estudadas. Houve similaridade da riqueza de carabídeos encontrada no fragmento florestal remanescente com a riqueza constatadas nos reflorestamentos, mesmo naqueles onde as coletas foram realizadas distante 3 Km do fragmento ou nas áreas de reflorestamento que não apresentavam conexão com o fragmento remanescente. Tetracha brasiliensis (Kirby) foi coletado quase que exclusivamente no reflorestamento sem conexão com o fragmento. Utilizando-se o teste de Kruskal-Wallis, não se constatou atratividade pelas diferentes iscas, no entanto verificou-se diferença significativa entre o número coletado nas armadilhas com iscas, quando comparado com o controle. A maior concentração de carabídeos coletados foi no período de dezembro a fevereiro, estação correspondente ao verão para a região estudada. A similaridade da riqueza de carabídeos encontrada entre os fragmentos de floresta e os reflorestamentos de mata ciliar, pode sugerir sucesso do método de reflorestamento, estando avançando para condições de característica primária. Diversity of Carabidae (Coleoptera) Samples in Areas of Riparian Reforestation and Forest Fragment, in the State of Paraná Abstract. Carabidae are Coleoptera whose most species have a predatory eating habit. The purpose of this paper was to study the diversity and abundance of Carabidae (Coleoptera) family in forest fragment areas and in reforestation areas of riparian vegetation, evidencing the importance of this group as a biodiversity indicator regarding the reforestation success. Beetles were sampled using soil pitfall traps in forest fragments and reforestation of riparian vegetation in three municipalities the state of Parana. The abundance of Carabidae was higher in riparian reforestation. The species Odontochila nodicornis (Dejean) was the most significantly abundant and found in all studied areas. There was a similarity in richness of Carabidae found in the remaining forest fragment, being the wealth found in reforestation, even where samples were collected 3km away from the fragment or in reforestation areas that did not have any connection with the remaining fragment. Tetracha brasiliensis (Kirby) was almost exclusively collected in reforestation unrelated to the fragment. Using the Kruskal-Wallis test, it was not noted any attraction of different baits, but there was a significant difference between the collection number in baited traps compared with the control. The highest concentration of Carabidae was collected from December to February, period corresponding to the summer season for the studied region. The similarity on the richness of Carabidae found between forest fragments and reforestation of riparian vegetation may suggest the reforestation method success, being able to advance to the primary characteristic.

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Diversite Floristique Et Structure Des Fragments Forestiers Du Sud-Ouest Du Parc National De La Comoe Apres Les Conflits Des Annees 2000 En Côte d’Ivoire

European Scientific Journal ESJ ◽

10.19044/esj.2017.v13n2p421 ◽

2017 ◽

Vol 13 (2) ◽

pp. 421

Author(s):

Yéo Zahana Seydou ◽

Sangne Yao Charles ◽

Barima Yao Sadaiou Sabas ◽

Bamba Issouf ◽

Kouakou Kouassi Apollinaire

Keyword(s):

Cote D'ivoire ◽

National Park ◽

Côte D’Ivoire ◽

Forest Fragments ◽

Forest Fragment ◽

Cote D’Ivoire ◽

Côte D'ivoire ◽

As Species ◽

Large Trees ◽

Good Potential

Côte d’Ivoire, like many countries in Africa, has experienced a decade of crises that has not been without consequences for the natural formations in general and protected areas in particular. The objective of this study is to evaluate the floristic diversity and structure of forest fragments Southwest of National Park of Comoé after conflicts. The sampling methodology was to inventory all taxa along 500 meters long and a width of 10 m (5 m either side of the main line) installed in each forest fragment. In addition to the inventory of taxa, we measured the circumference of all trees at least 30 cm with their corresponding pitch. A total of 12 transects were sampled in 12 fragments of forest. Following these inventories, 256 plant species have been identified, the most abundant belong to the families of Rubiaceae and Fabaceae. 23 species have been recognized as having a special status, including Salacia miegei N. Halle and Uvaria tortilis A. Chev. Ex Hutch. & Dalziel are endemic to the Côte d’Ivoire. Nine (9) others species have been identified as species of high commercial value for the quality of their wood. The forest formations are very dense with more than 550 trees / ha. It appears that the fragments contain few large trees. Despite the successive crises, it appears that forest fragments Southwest National Park Comoé still have good potential floristic.

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