Structure of ant-diaspore networks and their functional outcomes in a Brazilian Atlantic Forest

Ants are able to interact with fruits and seeds that are not adapted for ant seed dispersal. In Brazil, several studies show interactions of ants with non-myrmecochorous diaspores; however, few of them have studied the structure of ant-fruit networks. The use of the network approach allows visualising multiple interactions between partners and how they are shaped by the community context. Our study aims to investigate ant-fruit networks as well as quantitative and qualitative dispersal components in a fragment of the Brazilian Atlantic Forest. We investigated the structure of interaction networks, diaspore removal rates, diaspore destination and dispersal distance over two years of observation. We constructed three interaction networks: dry season, rainy season and total, with the latter comprising the two formers. The diaspore removal rate, dispersal distance and diaspore destination experiments were performed for the plant species Miconia calvescens, Miconia prasina, Psychotria leiocarpa and Inga edulis. We recorded a large number of interactions, with diaspore cleaning being more frequent than removal. Ant-diaspore networks were nested, non-modular and little specialized. M. calvescens, M. prasina and I. edulis showed higher diaspore removal rates. Diaspore removal distances were the same among M. calvescens, M. prasina and I. edulis. In M. calvescens and I. edulis, the main diaspore destination was the ant’s nest. Our study shows that diaspore cleaning is the most common behavior in ant-diaspore interactions and there are no differences in the organization of interaction networks over the seasons. These results have implications for the future structure of plant communities, considering that a small part of the diaspores is removed, and that most of them are cleaned, favouring germination at the deposition site.

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The role of ants in the removal of non-myrmecochorous diaspores and seed germination in a neotropical savanna

Journal of Tropical Ecology ◽

10.1017/s0266467407004087 ◽

2007 ◽

Vol 23 (3) ◽

pp. 343-351 ◽

Cited By ~ 45

Author(s):

Alexander V. Christianini ◽

Antônio J. Mayhé-Nunes ◽

Paulo S. Oliveira

Keyword(s):

Seed Germination ◽

Removal Rate ◽

Germination Rate ◽

Dispersal Distance ◽

Seed Fate ◽

Removal Rates ◽

Cerrado Savanna ◽

Neotropical Savannas ◽

Vertebrate Dispersal

Ants frequently interact with non-myrmecochorous diaspores on the ground in neotropical savannas. Our objective was to quantify the removal rate of these diaspores by ants and vertebrates in order to test the predator avoidance hypothesis, and to test how diaspore traits influence removal by ants and dispersal distance. We also investigated whether seed cleaning (removal of fruit matter simulating ant activity) can influence seed germination. We performed removal experiments with nine diaspore species in a reserve of cerrado savanna in south-east Brazil. Considerable differences in removal rates were found among the nine species. We found a positive linear relationship between lipid content and removal rates for five diaspore species. Vertebrate predation pressure was low for most species, limiting the benefits that ants can provide to plants to escape predators. Ants displace diaspores up to 25 m, which may increase the chance of a seed hitting a safe site. Smaller diaspores attain longer distances of dispersal than large ones. Seed cleaning increased the germination rate for five out of six species tested in greenhouse experiments. Ant activity can have relevant and possibly lasting effects on seed fate of plants adapted for vertebrate dispersal in the cerrado savanna.

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Analysis of organic removal rates in the aerated submerged fixed film process

Water Science & Technology ◽

10.2166/wst.1998.0809 ◽

1998 ◽

Vol 38 (8-9) ◽

pp. 213-221 ◽

Cited By ~ 3

Author(s):

Mohamed F. Hamoda ◽

Ibrahim A. Al-Ghusain

Keyword(s):

Pilot Plant ◽

Removal Rate ◽

Domestic Wastewater ◽

Removal Rates ◽

Hydraulic Loading ◽

Organic Removal ◽

Wide Range ◽

Fixed Film ◽

Cod Removal Rate ◽

And Performance

Performance data from a pilot-plant employing the four-stage aerated submerged fixed film (ASFF) process treating domestic wastewater were analyzed to examine the organic removal rates. The process has shown high BOD removal efficiencies (> 90%) over a wide range of hydraulic loading rates (0.04 to 0.68 m3/m2·d). It could also cope with high hydraulic and organic loadings with minimal loss in efficiency due to the large amount of immobilized biomass attained. The organic (BOD and COD) removal rate was influenced by the hydraulic loadings applied, but organic removal rates of up to 104 kg BOD/ m2·d were obtained at a hydraulic loading rate of 0.68 m3/m2·d. A Semi-empirical model for the bio-oxidation of organics in the ASFF process has been formulated and rate constants were calculated based on statistical analysis of pilot-plant data. The relationships obtained are very useful for analyzing the design and performance of the ASFF process and a variety of attached growth processes.

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The comparison of trichloroethylene removal rates by methane- and aromatic-utilizing microorganisms

Water Science & Technology ◽

10.2166/wst.1998.0272 ◽

1998 ◽

Vol 38 (7) ◽

pp. 19-24 ◽

Cited By ~ 3

Author(s):

C.-J. Lu ◽

C. M. Lee ◽

M.-S. Chung

Keyword(s):

Cell Concentration ◽

Removal Rate ◽

Carbon Sources ◽

Batch Reactors ◽

Initial Cell Concentration ◽

Removal Rates ◽

Initial Cell ◽

Toluene Concentration ◽

Cell Source ◽

Removal Efficiencies

The comparison of TCE cometabolic removal by methane, toluene, and phenol utilizers was conducted with a series of batch reactors. Methane, toluene, or phenol enriched microorganisms were used as cell source. The initial cell concentration was about 107 cfu/mL. Methane, toluene, and phenol could be readily biodegraded resulting in the cometabolic removal of TCE. Among the three primary carbon sources studied, the presence of phenol provided the best cometabolic removal of TCE. When the concentration of carbon source was 3 mg-C/L, the initial TCE removal rates initiated by methane, toluene, and phenol utilizers were 1.5, 30, and 100 μg/L-hr, respectively. During the incubation period of 80 hours, TCE removal efficiencies were 26% and 96% with the presence of methane and toluene, respectively. However, it was 100% within 20 hours with the presence of phenol. For phenol utilizers, the initial TCE removal rates were about the same, when the phenol concentrations were 1.35, 2.7, and 4.5 mg/L. However, TCE removal was not proportional to the concentrations of phenol. TCE removal was hindered when the phenol concentration was higher than 4.5 mg/L because of the rapid depletion of dissolved oxygen. The presence of toluene also initiated cometabolic removal of TCE. The presence of toluene at 3 and 5 mg/L resulted in similar TCE removal. The initial TCE removal rate was about 95 μg/L-hr at toluene concentrations of 3 and 5 mg/L compared to 20 μg/L-hr at toluene concentration of 1 mg/L.

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Relations between carbon removal rates, biofilm size and density of a novel anaerobic reactor: the inverse turbulent bed

Water Science & Technology ◽

10.2166/wst.2000.0453 ◽

2000 ◽

Vol 41 (4-5) ◽

pp. 253-260 ◽

Cited By ~ 4

Author(s):

P. Buffière ◽

R. Moletta

Keyword(s):

Removal Rate ◽

Removal Rates ◽

Carbon Removal ◽

Biofilm Growth ◽

Loading Rates ◽

Biomass Activity ◽

High Turbulence ◽

The One ◽

High Level ◽

Very High

An anaerobic inverse turbulent bed, in which the biogas only ensures fluidisation of floating carrier particles, was investigated for carbon removal kinetics and for biofilm growth and detachment. The range of operation of the reactor was kept within 5 and 30 kgCOD· m−3· d−1, with Hydraulic Retention Times between 0.28 and 1 day. The carbon removal efficiency remained between 70 and 85%. Biofilm size were rather low (between 5 and 30 μm) while biofilm density reached very high values (over 80 kgVS· m−3). The biofilm size and density varied with increasing carbon removal rates with opposite trends; as biofilm size increases, its density decreases. On the one hand, biomass activity within the reactor was kept at a high level, (between 0.23 and 0.75 kgTOC· kgVS· d−1, i.e. between 0.6 and 1.85 kgCOD·kgVS · d−1).This result indicates that high turbulence and shear may favour growth of thin, dense and active biofilms. It is thus an interesting tool for biomass control. On the other hand, volatile solid detachment increases quasi linearly with carbon removal rate and the total amount of solid in the reactor levels off at high OLR. This means that detachment could be a limit of the process at higher organic loading rates.

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The centipede genus Otostigmus Porat in Brazil: Description of three new species from the Atlantic Forest; a summary and an identification key to the Brazilian species of this genus (Chilopoda, Scolopendromorpha, Scolopendridae, Otostigminae)

Zootaxa ◽

10.11646/zootaxa.3280.1.1 ◽

2012 ◽

Vol 3280 (1) ◽

pp. 1 ◽

Cited By ~ 6

Author(s):

AMAZONAS CHAGAS-JÚNIOR

Keyword(s):

New Species ◽

Atlantic Forest ◽

The State ◽

Junior Synonym ◽

Identification Key ◽

Nominal Species ◽

Brazilian Atlantic Forest ◽

Three New Species ◽

First Time ◽

New Distribution

Three new species of Otostigmus Porat, 1876 from Brazilian Atlantic Forest are described. Otostigmus beckeri sp. n. andO. lanceolatus sp. n. are described from the state of Bahia and O. giupponii sp. n. from the state of Espírito Santo. InBrazil, the otostigmine scolopendrid genus Otostigmus comprises 22 species. A summary of Brazilian Otostigmus speciesis presented with new distribution records, taxonomic remarks when appropriate and an identification key. Otostigmus sul-catus Meinert, 1886 is recorded for the first time from Brazil; the Andean Otostigmus silvestrii Kraepelin 1903, previouslyrecorded from Brazil, is here considered not to be present in this country. Eight nominal species are regarded here as newsynonyms. Five of them—Otostigmus pradoi Bücherl, 1939, O. longistigma Bücherl, 1939, O. longipes Bücherl, 1939,O. langei Bücherl, 1946 and O. dentifusus Bücherl, 1946—are based on females of O. tibialis Brölemann, 1902. O. latipesBücherl, 1954 is conspecific with and is considered a junior synonym of O. sulcatus Meinert, 1886; O. limbatus diminutusBücherl, 1946 is a junior synonym of O. limbatus Meinert, 1886 and O. fossulatus Attems, 1928 is a junior synonym of O. goeldii Brölemann, 1898. A lectotype is designated for O. goeldii.

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Hide-and-Seek with Tiny Neotenic Beetles in One of the Hottest Biodiversity Hotspots: Towards an Understanding of the Real Diversity of Jurasaidae (Coleoptera: Elateroidea) in the Brazilian Atlantic Forest

Biology ◽

10.3390/biology10050420 ◽

2021 ◽

Vol 10 (5) ◽

pp. 420

Author(s):

Gabriel Biffi ◽

Simone Policena Rosa ◽

Robin Kundrata

Keyword(s):

Atlantic Forest ◽

Field Research ◽

Transitional Zone ◽

Biodiversity Hotspot ◽

Biodiversity Hotspots ◽

Brazilian Atlantic Forest ◽

Life Stages ◽

Adult Males ◽

Undescribed Species ◽

First Time

Jurasaidae are a family of neotenic elateroid beetles which was described recently from the Brazilian Atlantic Forest biodiversity hotspot based on three species in two genera. All life stages live in the soil, including the larviform females, and only adult males are able to fly. Here, we report the discovery of two new species, Jurasai miraculum sp. nov. and J. vanini sp. nov., and a new, morphologically remarkable population of J. digitusdei Rosa et al., 2020. Our discovery sheds further light on the diversity and biogeography of the group. Most species of Jurasaidae are known from the rainforest remnants of the Atlantic Forest, but here for the first time we report a jurasaid species from the relatively drier Atlantic Forest/Caatinga transitional zone. Considering our recent findings, minute body size and cryptic lifestyle of all jurasaids, together with potentially high numbers of yet undescribed species of this family from the Atlantic Forest and possibly also other surrounding ecoregions, we call for both field research in potentially suitable localities as well as for a detailed investigation of a massive amount of already collected but still unprocessed materials deposited in a number of Brazilian institutes, laboratories and collections.

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Sharing sound: Avian acoustic niches in the Brazilian Atlantic Forest

Biotropica ◽

10.1111/btp.12907 ◽

2021 ◽

Author(s):

Tristan Kleyn ◽

Mariane Cruz Kaizer ◽

Luiza F. Passos

Keyword(s):

Atlantic Forest ◽

Brazilian Atlantic Forest

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Vegetation trends in a protected area of the Brazilian Atlantic forest

Ecological Engineering ◽

10.1016/j.ecoleng.2021.106180 ◽

2021 ◽

Vol 162 ◽

pp. 106180

Author(s):

Rosane Gomes da Silva ◽

Alexandre Rosa dos Santos ◽

João Batista Esteves Pelúzio ◽

Nilton César Fiedler ◽

Ronie Silva Juvanhol ◽

...

Keyword(s):

Atlantic Forest ◽

Protected Area ◽

Brazilian Atlantic Forest

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Combining regional to local restoration goals in the Brazilian Atlantic forest

Regional Environmental Change ◽

10.1007/s10113-021-01792-0 ◽

2021 ◽

Vol 21 (3) ◽

Author(s):

Cassia M.G. Lemos ◽

Pedro R. Andrade ◽

Ricardo R. Rodrigues ◽

Leticia Hissa ◽

Ana P. D. Aguiar

Keyword(s):

Cost Effectiveness ◽

Atlantic Forest ◽

Natural Regeneration ◽

Regional Level ◽

Target Area ◽

Brazilian Atlantic Forest ◽

Regeneration Potential ◽

Allocation Model ◽

Alternative Scenarios ◽

The Cost

AbstractTo achieve regional and international large-scale restoration goals with minimum costs, several restoration commitments rely on natural regeneration, a passive and inexpensive strategy. However, natural regeneration potential may vary within the landscape, mainly due to its historical context. In this work, we use spatially explicit restoration scenarios to explore how and where, within a given region, multiple restoration commitments could be combined to achieve cost-effectiveness outcomes. Our goal is to facilitate the elaboration of forest restoration plans at the regional level, taking into consideration the costs for active and passive restoration methods. The approach includes (1) a statistical analysis to estimate the natural regeneration potential for a given area based on alternative sets of biophysical, land cover, and/or socioeconomic factors and (2) the use of a land change allocation model to explore the cost-effectiveness of combining multiple restoration commitments in a given area through alternative scenarios. We test our approach in a strategic region in the Brazilian Atlantic Forest Biome, the Paraiba Valley in São Paulo State. Using the available data for 2011, calibrated for 2015, we build alternative scenarios for allocating natural regeneration until 2025. Our models indicate that the natural regeneration potential of the region is actually very low, and the cost-effectiveness outcomes are similar for all scenarios. We believe our approach can be used to support the regional-level decision-making about the implementation of multiple commitments aiming at the same target area. It can also be combined with other approaches for more refined analysis (e.g., optimization models).

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