cometadata/datacite-titles-descriptions-related-identifiers huggingface dataset:
DOI: 10.6084/m9.figshare.20004930.v1
title: Patterns of mollusc distribution in mangroves from the São Marcos Bay, coast of Maranhão State, Brazil

description: ABSTRACT The diversity and distribution of molluscs from the Amazon Coast of Maranhão State, Brazil, are poorly understood. The aim of this study was to investigate how molluscs in two mangrove creeks (Buenos Aires and Tronco) at the São Marcos Bay, coast of the Maranhão State, respond to spatial and temporal variations in the environment. Sampling was performed in the intertidal area along three zones established using a straight line transect of 100 m. Abiotic variables of water and sediment were measured at each creek. We found 5,912 specimens belonging to 23 species and 15 families of epifaunal and infaunal molluscs. The patterns of their distribution in the two creeks were different. Salinity, dissolved oxygen, and rainfall were the main variables that affected the temporal distribution of molluscs. We found low species richness in the overall mollusc composition. Diversity in the Buenos Aires Creek was lower than that observed in the Tronco Creek, possibly because of activities of a port located in proximity to the former. The spatial distribution of molluscs along the zones followed an abundance and diversity gradient, mainly influenced by exposure time during low tide. Port activities may influence the patterns of mollusc distribution in the surrounding mangroves, and we thus highlight the importance of management and monitoring of these areas.
DOI: 10.6084/m9.figshare.20004932.v1
title: Identification key for the genera of Syrphidae (Diptera) from the Brazilian Amazon and new taxon records

description: ABSTRACT Identification keys are essential to properly recognize taxa, and a photographic key not only addresses that issue but can also attract the interest of the general public if designed correctly. Syrphidae is one of the largest families of Diptera, and the Brazilian Amazon holds more taxon records from this family than currently reported. The aim of the current study was to provide an updated photographic identification key, of easy use and access, to the genera of Syrphidae (Diptera) from the Brazilian Amazon region, and identify previously unrecorded taxa. Through a literature review and study of collection material from several institutions, I found 36 new taxon records for the Brazilian Amazon (15 are first records for Brazil) and provided a list of references with identification keys to species from each genus. The online version of this manuscript has a photographic identification key, with diagnostic pages for each genus, as supplementary material.
DOI: 10.6084/m9.figshare.20004932
title: Identification key for the genera of Syrphidae (Diptera) from the Brazilian Amazon and new taxon records

description: ABSTRACT Identification keys are essential to properly recognize taxa, and a photographic key not only addresses that issue but can also attract the interest of the general public if designed correctly. Syrphidae is one of the largest families of Diptera, and the Brazilian Amazon holds more taxon records from this family than currently reported. The aim of the current study was to provide an updated photographic identification key, of easy use and access, to the genera of Syrphidae (Diptera) from the Brazilian Amazon region, and identify previously unrecorded taxa. Through a literature review and study of collection material from several institutions, I found 36 new taxon records for the Brazilian Amazon (15 are first records for Brazil) and provided a list of references with identification keys to species from each genus. The online version of this manuscript has a photographic identification key, with diagnostic pages for each genus, as supplementary material.
DOI: 10.6084/m9.figshare.5816346
title: Population fluctuations in the pink hibiscus mealybug and its natural enemies in Annona squamosa (Annonaceae) in Roraima, Brazil

description: ABSTRACT Maconellicoccus hirsutus (Hemiptera, Pseudococcidae), a species of economic interest, especially for fruit plants, is expanding on the South American continent. Information about the population dynamics of this pest associated with control by natural enemies and cultural practices is fundamental for its management. Our objective was to study the population fluctuations in M. hirsutus and its natural enemies in a sugar-apple (Annona squamosa) orchard in Roraima, northern Brazil. Trees were evaluated monthly over a 12-month period. Infestation rates by M. hirsutus and its parasitism were also estimated for potential host plants around the study area. Highest infestation occurred in August and February-March. Alternative hosts were infested during the off-season, mainly fruit. Lacewings and the parasitoid Anagyrus kamali (Hymenoptera, Encyrtidae) were abundant natural enemies. Average parasitism by A. kamali in fruits was 50%, with highest rates in periods of greatest infestation by M. hirsutus. Fruitification pruning reduced M. hirsutus populations.
DOI: 10.6084/m9.figshare.5816346.v1
title: Population fluctuations in the pink hibiscus mealybug and its natural enemies in Annona squamosa (Annonaceae) in Roraima, Brazil

description: ABSTRACT Maconellicoccus hirsutus (Hemiptera, Pseudococcidae), a species of economic interest, especially for fruit plants, is expanding on the South American continent. Information about the population dynamics of this pest associated with control by natural enemies and cultural practices is fundamental for its management. Our objective was to study the population fluctuations in M. hirsutus and its natural enemies in a sugar-apple (Annona squamosa) orchard in Roraima, northern Brazil. Trees were evaluated monthly over a 12-month period. Infestation rates by M. hirsutus and its parasitism were also estimated for potential host plants around the study area. Highest infestation occurred in August and February-March. Alternative hosts were infested during the off-season, mainly fruit. Lacewings and the parasitoid Anagyrus kamali (Hymenoptera, Encyrtidae) were abundant natural enemies. Average parasitism by A. kamali in fruits was 50%, with highest rates in periods of greatest infestation by M. hirsutus. Fruitification pruning reduced M. hirsutus populations.
DOI: 10.6084/m9.figshare.5816466
title: Analysis of soybean cropland expansion in the southern Brazilian Amazon and its relation to economic drivers

description: ABSTRACT The agricultural dynamics of soybean expansion have long been recognized as a major driver of excessive land cover change on the southwestern border of the Brazilian Amazon. The hypothesis that the soybean market exerts an influence on land use was investigated by the association between economic indicators and soybean crop dynamics in the state of Mato Grosso (western Brazil). We integrated a historical series of satellite data of soybean cropland expansion and the two main economic variables (selling prices and production costs) for soybean in Mato Grosso. We focused on the relation between profit (the difference between the average soybean price and production costs) and land-use transition to soybean from 2001 to 2013. The spatially explicit analysis showed that the overall accuracy between the resulting first-time use and the most recent soybean crop area in 2013 was 96.75%, with a Kappa index of 0.63. However, dissimilar values found between Omission and Commission indicators suggest that most of the expanded areas prior to 2013 (5.57 million ha) were under a high dynamical range of land uses. Although there is no direct relation between either the deforestation rate or expansion trends (first-time-use rate) and profit, the results strongly suggest (R2=0.81) that profit exerts a direct and non-negligible influence on the evolution of consolidated land use for soybean in Mato Grosso State.
DOI: 10.6084/m9.figshare.5816466.v1
title: Analysis of soybean cropland expansion in the southern Brazilian Amazon and its relation to economic drivers

description: ABSTRACT The agricultural dynamics of soybean expansion have long been recognized as a major driver of excessive land cover change on the southwestern border of the Brazilian Amazon. The hypothesis that the soybean market exerts an influence on land use was investigated by the association between economic indicators and soybean crop dynamics in the state of Mato Grosso (western Brazil). We integrated a historical series of satellite data of soybean cropland expansion and the two main economic variables (selling prices and production costs) for soybean in Mato Grosso. We focused on the relation between profit (the difference between the average soybean price and production costs) and land-use transition to soybean from 2001 to 2013. The spatially explicit analysis showed that the overall accuracy between the resulting first-time use and the most recent soybean crop area in 2013 was 96.75%, with a Kappa index of 0.63. However, dissimilar values found between Omission and Commission indicators suggest that most of the expanded areas prior to 2013 (5.57 million ha) were under a high dynamical range of land uses. Although there is no direct relation between either the deforestation rate or expansion trends (first-time-use rate) and profit, the results strongly suggest (R2=0.81) that profit exerts a direct and non-negligible influence on the evolution of consolidated land use for soybean in Mato Grosso State.
DOI: 10.6084/m9.figshare.8092331
title: Evaluation of forest inventory processes in a forest under concession in the southwestern Brazilian Amazon

description: ABSTRACT Forest inventory procedures are of utmost importance to studies of wood volume stocks, and forest structure and diversity, which provide relevant information to public policies, management plans and ecological research. The present work focused on the performance of inventory techniques in the Amazon region to evaluate wood volume stocks with higher levels of accuracy while maintaining sampling intensity fixed. Two sampling processes were assessed: simple random sampling and two-stage cluster sampling. The processes were evaluated through the allocation of sampling units with different dimensions, and the effectiveness of the generated estimators was analyzed as a function of stand density and basal area. Simple random sampling resulted in the smallest errors, reaching 9% when all species were sampled together. The method depicted forest phytosociological parameters with greater sensitivity, whereas two-stage cluster sampling produced the least accurate estimators and presented slower responses to variation in phytosociological parameters.
DOI: 10.6084/m9.figshare.8092331.v1
title: Evaluation of forest inventory processes in a forest under concession in the southwestern Brazilian Amazon

description: ABSTRACT Forest inventory procedures are of utmost importance to studies of wood volume stocks, and forest structure and diversity, which provide relevant information to public policies, management plans and ecological research. The present work focused on the performance of inventory techniques in the Amazon region to evaluate wood volume stocks with higher levels of accuracy while maintaining sampling intensity fixed. Two sampling processes were assessed: simple random sampling and two-stage cluster sampling. The processes were evaluated through the allocation of sampling units with different dimensions, and the effectiveness of the generated estimators was analyzed as a function of stand density and basal area. Simple random sampling resulted in the smallest errors, reaching 9% when all species were sampled together. The method depicted forest phytosociological parameters with greater sensitivity, whereas two-stage cluster sampling produced the least accurate estimators and presented slower responses to variation in phytosociological parameters.
DOI: 10.6084/m9.figshare.9599576
title: New record of Blepharicnema splendens (Diptera, Calliphoridae, Luciliini) and range expansion in Caquetá, Colombia

description: ABSTRACT Blepharicnema splendens is a dipteran with occurrence restricted to the Neotropical Andean mountain forests from 1,400 to 2,500 masl. We surveyed the species using Van Someren-Rydon traps with decaying fish as bait in four sites (veredas) in the Eastern Cordillera, in the Municipality of Florencia, Caquetá, Colombia. A total of 221 individuals were collected in the four localities. The Vereda Las Brisas had the highest abundance, with 104 specimens (45.4%), followed by El Vergel, 76 (33.2%), Tarqui, 46 (20.1%) and Los Lirios, 2 (0.9%). The record of this species in the mountainous ecosystems of the Department of Caquetá expands the known distribution of B. splendens and adds to the incipient knowledge on the diversity of Diptera in this region.
DOI: 10.6084/m9.figshare.9599576.v1
title: New record of Blepharicnema splendens (Diptera, Calliphoridae, Luciliini) and range expansion in Caquetá, Colombia

description: ABSTRACT Blepharicnema splendens is a dipteran with occurrence restricted to the Neotropical Andean mountain forests from 1,400 to 2,500 masl. We surveyed the species using Van Someren-Rydon traps with decaying fish as bait in four sites (veredas) in the Eastern Cordillera, in the Municipality of Florencia, Caquetá, Colombia. A total of 221 individuals were collected in the four localities. The Vereda Las Brisas had the highest abundance, with 104 specimens (45.4%), followed by El Vergel, 76 (33.2%), Tarqui, 46 (20.1%) and Los Lirios, 2 (0.9%). The record of this species in the mountainous ecosystems of the Department of Caquetá expands the known distribution of B. splendens and adds to the incipient knowledge on the diversity of Diptera in this region.
DOI: 10.6084/m9.figshare.8092328
title: Do polyembryonic seeds of Carapa surinamensis (Meliaceae) have advantages for seedling development?

description: ABSTRACT Polyembryony is the differentiation and development of multiple embryos in a single seed. This characteristic can provide advantages, as more than one embryo is produced with the same amount of resources, and the probability of establishment of at least one seedling increases. However, sibling seedlings may also increase competition, affecting development and survival. In the present study, the possible advantages and disadvantages of polyembryony were analyzed in the initial establishment of seedlings of Carapa surinamensis (Meliaceae), a tree species that produces monoembryonic or polyembryonic seeds. In this regard, the development of single seedlings was compared with a pair of seedlings emerging from polyembryonic seeds. We compared the development of seedlings attached to or detached from each other and to the seed resources. We observed two levels of competition: (a) for the seed reserves during germination and initial development, as multiple embryos of C. surinamensis share the same reserves, and (b) for external factors, mostly space for root and shoot development, and also for light. Reducing the competition for external factors by separating the siblings was not enough to reduce the effects of competition for seed reserves in the first six months of development. Nevertheless, viable seedlings were produced in all treatments. Thus, depending on sprout management in the nursery, the number of seedlings per seed can be significantly increased by detaching the seedlings, or more vigorous seedlings can be obtained when only one seedling is maintained.
DOI: 10.6084/m9.figshare.8092328.v1
title: Do polyembryonic seeds of Carapa surinamensis (Meliaceae) have advantages for seedling development?

description: ABSTRACT Polyembryony is the differentiation and development of multiple embryos in a single seed. This characteristic can provide advantages, as more than one embryo is produced with the same amount of resources, and the probability of establishment of at least one seedling increases. However, sibling seedlings may also increase competition, affecting development and survival. In the present study, the possible advantages and disadvantages of polyembryony were analyzed in the initial establishment of seedlings of Carapa surinamensis (Meliaceae), a tree species that produces monoembryonic or polyembryonic seeds. In this regard, the development of single seedlings was compared with a pair of seedlings emerging from polyembryonic seeds. We compared the development of seedlings attached to or detached from each other and to the seed resources. We observed two levels of competition: (a) for the seed reserves during germination and initial development, as multiple embryos of C. surinamensis share the same reserves, and (b) for external factors, mostly space for root and shoot development, and also for light. Reducing the competition for external factors by separating the siblings was not enough to reduce the effects of competition for seed reserves in the first six months of development. Nevertheless, viable seedlings were produced in all treatments. Thus, depending on sprout management in the nursery, the number of seedlings per seed can be significantly increased by detaching the seedlings, or more vigorous seedlings can be obtained when only one seedling is maintained.
DOI: 10.6084/m9.figshare.20004936
title: Degree of seed desiccation sensitivity of the Amazonian palm Oenocarpus bacaba depends on the criterion for germination

description: ABSTRACT Across the seed-seedling transition, several germination criteria are used in studies of palm-seed germination. In Oenocarpus bataua, these criteria have differential tolerance to thermal stress. In this study, we evaluated the tolerance of germination criteria to seed desiccation of the congeneric Oenocarpus bacaba. We dried seeds to different moisture contents (MC) before scoring first cataphyll, second cataphyll, enclosed eophyll and expanded eophyll. Seeds without drying had 41.7% MC. Germination success reached close to 70% after 75 and 105 days, depending on the germination criterion. Safe MC was close to initial MC and all seeds were dead with MC &lt; 26.7%. As the primordial organs of the cataphylls and the eophyll are already detectable in the palm-seed embryo, all were affected by drying. Critical MC, defined here as 50% loss of germination capacity, increased from 35.4% (first cataphyll) to 37.1% (expanded eophyll) and confirmed that, across the seed-seedling transition, more advanced germination stages had a higher sensitivity to desiccation. During germination and development, the criteria appear in sequence over several weeks. Consequently, the desiccation damage was only detectable when the last criterion was evaluated. To avoid an underestimation of damages, we suggest that seed-stress studies in palms should take into account an adequate period for seedling development, which, for O. bacaba, was 105 days until the expansion of the eophyll.
DOI: 10.6084/m9.figshare.20004936.v1
title: Degree of seed desiccation sensitivity of the Amazonian palm Oenocarpus bacaba depends on the criterion for germination

description: ABSTRACT Across the seed-seedling transition, several germination criteria are used in studies of palm-seed germination. In Oenocarpus bataua, these criteria have differential tolerance to thermal stress. In this study, we evaluated the tolerance of germination criteria to seed desiccation of the congeneric Oenocarpus bacaba. We dried seeds to different moisture contents (MC) before scoring first cataphyll, second cataphyll, enclosed eophyll and expanded eophyll. Seeds without drying had 41.7% MC. Germination success reached close to 70% after 75 and 105 days, depending on the germination criterion. Safe MC was close to initial MC and all seeds were dead with MC &lt; 26.7%. As the primordial organs of the cataphylls and the eophyll are already detectable in the palm-seed embryo, all were affected by drying. Critical MC, defined here as 50% loss of germination capacity, increased from 35.4% (first cataphyll) to 37.1% (expanded eophyll) and confirmed that, across the seed-seedling transition, more advanced germination stages had a higher sensitivity to desiccation. During germination and development, the criteria appear in sequence over several weeks. Consequently, the desiccation damage was only detectable when the last criterion was evaluated. To avoid an underestimation of damages, we suggest that seed-stress studies in palms should take into account an adequate period for seedling development, which, for O. bacaba, was 105 days until the expansion of the eophyll.
DOI: 10.6084/m9.figshare.11930211.v1
title: Rapid assessment of the ichthyofauna of the southern Guiana Shield tributaries of the Amazonas River in Pará, Brazil

description: ABSTRACT The Northern Pará Drainage System encompasses the left-bank tributaries of the Amazonas River in the southern Guiana Shield region of Pará state, Brazil. Five of the region’s state protected areas are considered strategic for the conservation of its biodiversity. In the present study, we assessed the ichthyofauna of the five state protected areas of the Northern Pará Drainage System. Seven expeditions were conducted between January 2008 and January 2009, which surveyed stretches of the Cuminá, Cuminapanema, Curuá, Jari, Mapuera, Nhamundá, and Paru rivers. These surveys yielded 286 species belonging to 38 families and eight orders, including seven new records of fish species for Brazil, six of which are also new records for the Amazon basin. Our results provide a valuable database for future research and conservation programs in the protected areas of the region.
DOI: 10.6084/m9.figshare.11930211
title: Rapid assessment of the ichthyofauna of the southern Guiana Shield tributaries of the Amazonas River in Pará, Brazil

description: ABSTRACT The Northern Pará Drainage System encompasses the left-bank tributaries of the Amazonas River in the southern Guiana Shield region of Pará state, Brazil. Five of the region’s state protected areas are considered strategic for the conservation of its biodiversity. In the present study, we assessed the ichthyofauna of the five state protected areas of the Northern Pará Drainage System. Seven expeditions were conducted between January 2008 and January 2009, which surveyed stretches of the Cuminá, Cuminapanema, Curuá, Jari, Mapuera, Nhamundá, and Paru rivers. These surveys yielded 286 species belonging to 38 families and eight orders, including seven new records of fish species for Brazil, six of which are also new records for the Amazon basin. Our results provide a valuable database for future research and conservation programs in the protected areas of the region.
DOI: 10.6084/m9.figshare.20004939.v1
title: Phenology and fruit set comparison of camu-camu (Myrciaria dubia) in a natural population and a plantation in the central Amazon, Brazil

description: ABSTRACT Myrciaria dubia (Myrtaceae) is a shrub that produces fruits with high concentrations of ascorbic acid (1380 to 1490 mg 100 g-1 of pulp and 2050 mg 100 g-1 of peel), 20 times more than acerola and 100 times more than lemon. Native to the Amazon region, it occurs naturally on the seasonally-flooded banks of lakes and rivers, but also has been cultivated commercially in terra firme. In this study, phenological observations and fruit yield evaluations were carried out in a natural population of camu-camu in a floodplain habitat and a plantation in terra firme in central Amazonia. Biweekly visits were made over one year to collect data on flowering, fruiting and leaf phenology. At the height of flowering, flower buds were marked and tracked until fruit matured and were harvested for biometrics and seed counting. Fruits varied from 1.01 to 2.73 cm in diameter and 1.14 to 10.87 g in weight and fruit production was higher in the wild stand. Phenology differed between habitats and phenophase synchrony was higher in the natural population. Despite being native to flooplain forests, fruit production in terra firme occurred throughout the year, suggesting that there are few restrictions on fruit development in cultivated plantation.