Litterfall production and fluvial export in headwater catchments of the southern Amazon

Resolving the carbon (C) balance in the Amazonian forest depends on an improved quantification of production and losses of particulate C from forested landscapes via stream export. The main goal of this work was to quantify litterfall, the lateral movement of litter, and the export of coarse organic particulate matter (>2 mm) in four small watersheds (1–2 ha) under native forest in southern Amazonia near Juruena, Mato Grosso, Brazil (10°25′S, 58°46′W). Mean litterfall production was 11.8 Mg ha−1 y−1 (5.7 Mg C ha−1 y−1). Litterfall showed strong seasonality, with the highest deposition in the driest months of the year. About two times more C per month was deposited on the forest floor during the 6-mo dry season (0.65 Mg C ha−1 mo−1) compared with the rainy season (0.3 Mg C ha−1 mo−1). The measured C concentration of the litterfall samples was significantly greater in the dry season than in the rainy season (49% vs. 46%). The lateral movement of litter increased from the plateau (upper landscape position) towards the riparian zone. However, the trend in C concentration of laterally transported litter samples was the opposite, being highest on the plateau (44%) and lowest in the riparian zone (42%). Stream-water exports of particulate C were positively correlated with streamflow, increasing in the rainiest months. The export of particulate C in streamflow was found to be very small (less than 1%) in relation to the amount of litterfall produced.

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First occurrence of Quadrigyrus nickoli (Acanthocephala) in the ornamental fishHyphessobrycon eques

Revista Brasileira de Parasitologia Veterinária ◽

10.1590/s1984-29612013000100020 ◽

2013 ◽

Vol 22 (1) ◽

pp. 110-113 ◽

Cited By ~ 5

Author(s):

Rodrigo Yudi Fujimoto ◽

Edilene Santos Almeida ◽

Daniel Guerreiro Diniz ◽

Jorge Costa Eiras ◽

Mauricio Laterça Martins

Keyword(s):

Rainy Season ◽

Paratenic Host ◽

Dry Season ◽

Amazon Region ◽

Seasonal Occurrence ◽

Mato Grosso ◽

First Occurrence

The objective of this work was to report the first seasonal occurrence of the acanthocephalan Quadrigyrus nickoliSchmidt & Hugghins, 1973(Quadrigyridae), in the “Mato Grosso”Hyphessobrycon eques (Characidae) (Steindachner, 1882), collected from the Chumucuí River, state of Pará, Brazil. The fish were collected between July 2006 (rainy season) and June 2007 (dry season) and were examined for parasites using pattern techniques. A total of 75 parasites were found in the stomach and intestine. Among 83 fish examined (50 in the dry season and 33 in the rainy season), 22 were parasitized by cystacanths of Q. nickoli. The importance of H. eques as a paratenic host for Q. nickoli is discussed. This is the first study on the biology of and infection by Q. nickoli occurring in the eastern Amazon region.

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Zooplankton community structure of two marginal lakes of the River Cuiabá (Mato Grosso, Brazil) with analysis of Rotifera and Cladocera diversity

Brazilian Journal of Biology ◽

10.1590/s1519-69842003000200018 ◽

2003 ◽

Vol 63 (2) ◽

pp. 329-343 ◽

Cited By ~ 46

Author(s):

I. F. Neves ◽

O. Rocha ◽

K. F. Roche ◽

A.A. Pinto

Keyword(s):

Rainy Season ◽

Zooplankton Community ◽

Taxonomic Composition ◽

Domestic Sewage ◽

Dry Season ◽

Zooplankton Community Structure ◽

Keratella Cochlearis ◽

Mato Grosso ◽

Littoral Region ◽

Mato Grosso Do Sul

In the present study, two small lakes on the margins of the River Cuiabá were analyzed regarding taxonomic composition and population densities of the zooplankton. Diversity was evaluated for two groups, Rotifera and Cladocera; sampling was carried out on two dates: 2 March 1999, in the rainy season, and 25 August 1999, in the dry season. Seventy-nine rotifer taxa, 30 cladoceran taxa, and 6 copepod taxa were found. Comparing the species identified in the present study with those recorded by other authors for several water bodies in Mato Grosso and Mato Grosso do Sul states, it was found that 9 species of Cladocera, 2 of Copepoda, and 14 of Rotifera are new records for the region. The most abundant rotifer species were Keratella cochlearis, Brachionus angularis, Polyarthra vulgaris, and Keratella americana. Moina minuta and Bosminopsis deitersi were dominant among the cladocerans, and Notodiaptomus transitans and N. devoyorum among the copepods. Comparing both lakes, the greatest species richness of both Rotifera and Cladocera was observed in Lake Souza Lima, during the rainy season. This is probably linked to the fact that the littoral region of this lake is densely colonized by macrophytes. The lake also has better environmental conditions since it does not receive domestic sewage inputs, as does Lake Parque Atalaia. The diversity of the Rotifera was markedly low in Lake Parque Atalaia, during the dry season, again perhaps linked domestic sewage input found in this water body.

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Photosynthetic performance and anatomical adaptations in Byrsonima sericea DC. under contrasting light conditions in a remnant of the Atlantic forest

Brazilian Journal of Plant Physiology ◽

10.1590/s1677-04202010000400004 ◽

2010 ◽

Vol 22 (4) ◽

pp. 245-254 ◽

Cited By ~ 12

Author(s):

Anandra S. Silva ◽

Jurandi G. Oliveira ◽

Maura da Cunha ◽

Angela P. Vitória

Keyword(s):

Net Photosynthetic Rate ◽

Photosynthetic Rate ◽

Rainy Season ◽

Photosynthetic Pigment ◽

Photosynthetic Performance ◽

Dry Season ◽

Limiting Factor ◽

Native Forest ◽

The Sun ◽

Adaxial Epidermis

The photosynthetic dynamics of the tropical pioneer species, Byrsonima sericea DC., were studied during the regeneration process of a native forest by evaluating ecophysiological (gas exchange, chlorophyll a fluorescence and photosynthetic pigment contents) and anatomical parameters of plants in sunny and shady environments. Ecophysiological evaluations were carried out monthly for one year, encompassing both a dry and a rainy season. Byrsonima sericea DC. presents anatomical plasticity that enables it to establish in environments with contrasting light regimes. In sunny conditions, it produced a thicker leaf (about 420 mm) and flat adaxial epidermis, whilst in the shade, leaves had a thinner convex adaxial epidermis (about 395 mm). No differences were found in the compositions of the pigments in the different environments, however, during the dry season, the plants presented a significantly higher concentration of photosynthetic pigments. In the sun, plants showed decreases in Fv/F0 ratio (in the rainy season) and NPQ (in the dry season), but no difference was observed between plants that were in the sun or in the shade. A significantly higher net photosynthetic rate was found only in the rainy season in the plants in the sun, compared to shaded plants (9.9±0.8 and 7.4±0.3 µmol m-2s-1, respectively). Significant increase in transpiration was observed in plants in the shade during the dry season, but no alterations were observed in the water use efficiency. Ecophysiological data suggest that mainly plants overexposed to the sun underwent water limitations during the dry season and that, in the rainy season, these plants increased their net photosynthetic rate, possibly due to the greater drainage force resulting from increased growth during this period. Data suggest that anatomic alterations, namely the convex adaxial epidermis, could aid in the supply of light to shaded plants during both seasons, precluding changes in the pigments, such as the increase in chlorophyll b usually observed in shaded plants, but not detected in the present study. Another consequence of the greater quantity of light captured by these shade plants is that during the dry season their net photosynthetic rate was not different from that of plants in a sunny environment. However, when water was not a limiting factor, a better photosynthetic performance was observed in this pioneer specie in open spaces.

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Soil macrofauna as a bioindicator of soil quality in successional agroforestry systems

Research Society and Development ◽

10.33448/rsd-v10i10.19144 ◽

2021 ◽

Vol 10 (10) ◽

pp. e580101019144

Author(s):

Rafaela Martins da Silva ◽

Rakiely Martins da Silva ◽

Sandra Santana de Lima ◽

Jianne Rafaela Mazzini de Souza ◽

Jheny Kesley Mazzini de Souza ◽

...

Keyword(s):

Soil Quality ◽

Rainy Season ◽

Agroforestry System ◽

Agroforestry Systems ◽

Dry Season ◽

Native Forest ◽

Secondary Forests ◽

Euterpe Oleracea ◽

Soil Macrofauna ◽

Time Of Collection

The objective of this study was to evaluate soil macrofauna as a bioindicator of soil quality in successional agroforestry systems and secondary forests. The study was conducted in the southern lower region of Bahia in Brazil, in two areas: a successional agroforestry system (AFS18) and native forest (NF). AFS18 consists of two species: mahogany (Khaya ivorensis and Khaya grandifoliola), açaí (Euterpe oleracea), cacao (Theobroma cacau) and banana (Musa spp.). Sampling was carried out in the dry (June) and rainy (October) seasons of 2019, and eight soil monoliths were collected in both areas. A total of 889 individuals from the soil macrofauna were sampled. The highest frequency (RF) of taxons occurred in NF in the rainy season, and the groups that stood out were: Oligochaeta with 42% FR in ASF18, Formicide with 33.9% in NF and Isoptera with 58% in AFS18. The macrofauna structure of the soil varied according to the time of collection. The density of macrofauna individuals differed between areas only in the dry season. The highest number of ind.m² was observed in the area NF (378) when compared to ASF18 (196). TOC, Mg2+, Al3+ and CTC were related to AF on both occasions of collection and AFS18 in the rainy season, K+, P and pH were associated with AFS18 in the dry season. The diversity, equitability and richness of the soil macrofauna was greater in AF area. HFA18 in the rainy season was similar to NF, favoring colonization of the area by soil macrofauna organisms.

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BIODIVERSIDADE DE BACTÉRIAS ANTAGÔNICAS A FUNGOS ASSOCIADOS À SINDROME DA MORTE DO CAPIM-MARANDU (Brachiaria brizantha)

Nativa ◽

10.31413/nativa.v9i5.12666 ◽

2021 ◽

Vol 9 (5) ◽

pp. 454-459

Author(s):

Maira Laís Both Bourscheidt ◽

Kellen Banhos do Carmo ◽

Bruno Carneiro Pedreira ◽

Gilcele de Campos Martin Berber ◽

Anderson Ferreira

Keyword(s):

Biological Control ◽

Rainy Season ◽

Production Systems ◽

Dry Season ◽

Native Forest ◽

Bacterial Isolates ◽

Fusarium Spp ◽

Brachiaria Brizantha

A síndrome da morte do capim-marandu (Brachiaria brizantha) é um dos principais problemas na degradação das pastagens no bioma Amazônia. A morte das forrageiras ocorre durante a época chuvosa por suscetibilidade a fitopatógenos. Assim, objetivou-se estudar sistemas de produção e selecionar bactérias antagônicas a Fusarium spp., um dos agentes fitopatogênicos. Os isolados bacterianos foram obtidos de 10 sistemas de produção, mata nativa e pousio, na chuva e na seca. Realizou-se a caracterização molecular de isolados por sequenciamento. Dois isolados de Fusarium foram testados. Para o patógeno 1, na época da chuva, 7,5% dos isolados apresentaram antagonismo enquanto na seca foi 15%. Para o patógeno 2, nem todos os isolados positivos para o patógeno 1 foram eficientes no controle, demonstrando a ocorrência de interações entre isolados bacterianos e Fusarium spp. Na chuva, para o patógeno 1, a mata apresentou maior número de isolados positivos (20%). Na seca, os tratamentos mata, 1-Floresta e 8-integração lavoura floresta para o patógeno 1, foram os que apresentaram maior número de positivos (25%). Na identificação molecular, 8 foram os gêneros bacterianos encontrados: Burkholderia, Bacillus, Brevibacillus, Streptomyces, Pseudomonas, Escherichia, Paenibacillus e Pandoraea, em que a maioria é descrita como capaz de controlar Fusarium spp. in vitro. Palavras-chave: Burkholderia; controle biológico; integração lavoura-pecuária-floresta. Biodiversity of bacteria antagonic to fungi associated with syndrome's death palisadegrass (Brachiaria brizantha) ABSTRACT: The death syndrome of marandu grass (Brachiaria brizantha) is one of the main problems in the degradation of pastures in the Amazon biome. Plant death occurs during the rainy season due to susceptibility to phytopathogens. Thus, the objective was to study production systems and select bacteria antagonistic to Fusarium spp., one of the phytopathogenic agents. Bacterial isolates were obtained from 10 production systems, native forest and fallow, in rain and drought season. Molecular characterization of isolates was carried out by sequencing. Two Fusarium isolates were assessed. For pathogen 1, in the rainy season, 7.5% of the isolates showed antagonism, while in the dry season it was 15%. For pathogen 2, not all isolates positive for pathogen 1 were efficient in the control, showing correlations between bacterial isolates and Fusarium spp. In the rain, for pathogen 1, the forest showed the highest number of positive isolates (20%). In the dry season, the treatments forest, 1-Forest and 8-plant-forest integration for pathogen 1, were ones with the highest number of positives (25%). In the molecular identification, 8 bacterial genera were found: Burkholderia, Bacillus, Brevibacillus, Streptomyces, Pseudomonas, Escherichia, Paenibacillus and Pandoraea, most of which are described as able to controlling Fusarium spp. in vitro. Keywords: Burkholderia; biological control; integrated crop-livestock-forest.

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Evaluation of Hydrological Alterations at the Sub-Daily Scale Caused by a Small Hydroelectric Facility

Water ◽

10.3390/w13020206 ◽

2021 ◽

Vol 13 (2) ◽

pp. 206

Author(s):

Camila C. Braun-Cruz ◽

Hans Mario Tritico ◽

Renato Leandro Beregula ◽

Pierre Girard ◽

Peter Zeilhofer ◽

...

Keyword(s):

Rainy Season ◽

Dry Season ◽

Hydropower Plant ◽

Wet Season ◽

Small Hydropower ◽

Mato Grosso ◽

High Magnitude ◽

Daily Frequency ◽

Daily Scale ◽

Hydrologic Conditions

This work aims to evaluate the hydrologic changes caused by a small hydropower plant on the watercourse in which it is installed. Since hydrologic research with data of temporal frequencies less than a day is less common than daily measurements, there are few indicators and methodologies capable of treating such records. For this reason, 17 indicators are proposed which describe the magnitude, duration, frequency and rate of changes in hydrologic conditions occurring in a watercourse at a sub-daily frequency. These 17 indicators were used to assess changes in the flow regimes at sub-daily scales across the Itiquira hydroelectric facility in Mato Grosso, Brazil. During the dry season the river was more susceptible to hydroelectric operations than during the wet season. Eighty-eight percent of the proposed indicators were significantly altered during the dry season compared to 71% during the rainy season. In addition to the number of indicators that changed between the seasons, the magnitude of the change was different. During the dry season, 53% of the magnitudes of the proposed indicators were classified as having a high magnitude of change, while in the rainy season only 6% of the indicators were characterized as having a high magnitude of change.

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Optical and SAR Remote Sensing Synergism for Mapping Vegetation Types in the Endangered Cerrado/Amazon Ecotone of Nova Mutum—Mato Grosso

Remote Sensing ◽

10.3390/rs11101161 ◽

2019 ◽

Vol 11 (10) ◽

pp. 1161 ◽

Cited By ~ 4

Author(s):

Flávia de Souza Mendes ◽

Daniel Baron ◽

Gerhard Gerold ◽

Veraldo Liesenberg ◽

Stefan Erasmi

Keyword(s):

Remote Sensing ◽

Rainy Season ◽

Secondary Forest ◽

Principal Component ◽

Dry Season ◽

Vegetation Types ◽

Alos Palsar ◽

Mato Grosso ◽

Radar Images ◽

Sentinel 2A

Mapping vegetation types through remote sensing images has proved to be effective, especially in large biomes, such as the Brazilian Cerrado, which plays an important role in the context of management and conservation at the agricultural frontier of the Amazon. We tested several combinations of optical and radar images to identify the four dominant vegetation types that are prevalent in the Cerrado area (i.e., cerrado denso, cerradão, gallery forest, and secondary forest). We extracted features from both sources of data such as intensity, grey level co-occurrence matrix, coherence, and polarimetric decompositions using Sentinel 2A, Sentinel 1A, ALOS-PALSAR 2 dual/full polarimetric, and TanDEM-X images during the dry and rainy season of 2017. In order to normalize the analysis of these features, we used principal component analysis and subsequently applied the Random Forest algorithm to evaluate the classification of vegetation types. During the dry season, the overall accuracy ranged from 48 to 83%, and during the dry and rainy seasons it ranged from 41 up to 82%. The classification using Sentinel 2A images during the dry season resulted in the highest overall accuracy and kappa values, followed by the classification that used images from all sensors during the dry and rainy season. Optical images during the dry season were sufficient to map the different types of vegetation in our study area.

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Litterfall production in intact and selectively logged forests in southern of Amazonia as a function of basal area of vegetation and plant density

Acta Amazonica ◽

10.1590/1809-4392201402543 ◽

2015 ◽

Vol 45 (2) ◽

pp. 157-166 ◽

Cited By ~ 7

Author(s):

Everton José ALMEIDA ◽

Flávio LUIZÃO ◽

Domingos de Jesus RODRIGUES

Keyword(s):

Plant Density ◽

Nutrient Recycling ◽

Canopy Cover ◽

Basal Area ◽

Amazon Rainforest ◽

Anthropogenic Factors ◽

Mato Grosso ◽

Litterfall Production ◽

Average Annual Production ◽

Southern Amazonia

Nutrient recycling in the forest is linked to the production and decomposition of litter, which are essential processes for forest maintenance, especially in regions of nutritionally poor soils. Human interventions in forest such as selecttive logging may have strong impacts on these processes. The objectives of this study were to estimate litterfall production and evaluate the influence of environmental factors (basal area of vegetation, plant density, canopy cover, and soil physicochemical properties) and anthropogenic factors (post-management age and exploited basal area) on this production, in areas of intact and exploited forest in southern Amazonia, located in the northern parts of Mato Grosso state. This study was conducted at five locations and the average annual production of litterfall was 10.6 Mg ha-1 year-1, higher than the values for the Amazon rainforest. There were differences in litterfall productions between study locations. Effects of historical logging intensity on litterfall production were not significant. Effects of basal area of vegetation and tree density on litterfall production were observed, highlighting the importance of local vegetation characteristics in litterfall production. This study demonstrated areas of transition between the Amazonia-Cerrado tend to have a higher litterfall production than Cerrado and Amazonia regions, and this information is important for a better understanding of the dynamics of nutrient and carbon cycling in these transition regions.

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Morphometry, floral resources and efficiency of natural and artificial pollination in fruit quality in cultivars of sour passion fruit

Revista Brasileira de Fruticultura ◽

10.1590/0100-29452018171 ◽

2018 ◽

Vol 40 (3) ◽

Author(s):

Laís Alves Lage ◽

Willian Krause ◽

Celice Alexandre Silva ◽

Daianny Correia Dias ◽

Moisés Ambrósio ◽

...

Keyword(s):

Rainy Season ◽

Pollen Viability ◽

Climatic Conditions ◽

Dry Season ◽

Passion Fruit ◽

Floral Resources ◽

Improvement Program ◽

Mato Grosso ◽

Artificial Pollination ◽

Sour Passion Fruit

Abstract This study aimed to provide information on the biology and floral resources, stigmatic receptivity and viability of pollen grains during rainy season and dry season, and to evaluate the efficiency of natural and artificial pollination on quality of fruits of eight passion fruit cultivars sourced in Tangará da Serra - MT. Five commercial cultivars and three populations of the genetic improvement program of the sour passion fruit from the Universidade do Estado de Mato Grosso were evaluated. The climatic conditions of the rainy season favored the greater development of the floral pieces. The sugar concentration in the nectar presented higher averages in the rainy season, in all cultivars, except for FB 200. The climatic conditions of the dry season favored the replacement of the nectar volume. All cultivars evaluated presented pollen viability and stigmatic receptivity higher than 79% and 90%, respectively. The characteristics of fruit mass and percentage of pulp were better in artificial pollination, and the fruits obtained from natural and artificial pollination in all cultivars evaluated presented physical and chemical characteristics that are within the quality standards desired in the commercialization.

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PHENOLOGY OF Copernicia alba IN FLOODED AND NOT FLOODED ENVIRONMENTS

FLORESTA ◽

10.5380/rf.v51i1.68070 ◽

2020 ◽

Vol 51 (1) ◽

pp. 220

Author(s):

Maicon Marinho Vieira Araujo ◽

Francisco Almeida Lobo

Keyword(s):

Rainy Season ◽

Transition Period ◽

Dry Season ◽

Dry Period ◽

Mato Grosso ◽

Floral Buds

The objective of this study is to describe the reproductive and vegetative phenological patterns of individuals of Copernicia alba, popularly known as "carandá", present in a flooded and non-flooded environment and to test the relations between vegetative and reproductive phenophasesand climatic seasonality. The phenological aspects of the carandá were obtained through a biweekly observation of 22 individuals from two areas of the Pantanal of Mato Grosso between August 2015 and August 2017. The carandá population presented a perennial behavior, flowering during the dry season and a greater leaf intensity in the transition period to the rainy season. Budding, although continuous, was intense in the rainy season, and the leaf deciduous pattern had a direct interference from the absence of rainfalls in the dry period. The incidence of floral buds occurred in the dry period, and the flowering occurred between the dry and rainy periods. The fruiting period occurred in the rainy season, indicating a high synchronism of phenophases.

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