Social wasps are among the most curious non-ant insects known to harvest food bodies of Cecropia Loefl. The aim of this note is to describe for the first time: (1) interactions between wasp species ...which harvest food bodies; (2) interactions of these wasps with other insects associated to Cecropia (ants, assassin bugs); (3) the use of a food resource different from müllerian bodies; and (4) wasp species whose association with Cecropia was unknown until now. All records were made in Manaus region and in Uatumã Sustainable Development Reserve (Amazonas State, Brazil), with the aid of a digital camera. The wasp and ant species involved were captured for later identification. The recorded wasp species were: Charterginus xanthura Saussure, 1854, Protopolybia chartergoides Gribodo, 1891, Protopolybia minutissima Spinola, 1851, and Synoeca virginea Fabricius, 1804 (Hymenoptera: Vespidae). The findings corroborate the importance of food bodies not only for Azteca Forel, 1878 ants, but also for other social insects.
Defaunation shadow on mutualistic interactions Costa-Pereira, Raul; Lucas, Christine; Crossa, Marcelo ...
Proceedings of the National Academy of Sciences - PNAS,
2018-Mar-20, Letnik:
115, Številka:
12
Journal Article
Recenzirano
Odprti dostop
Tregidgo et al show that size-selective overfishing has drastically depleted and downsized populations of tambaqui (Colossoma macropomum) along the Purus River, Amazonia. Because fishers have ...historically targeted the largest individuals, tambaqui ~1,000 km upriver are twofold larger than those near the Manaus rainforest metropolis. Here, the authors demonstrate that this overfishing shadow has cascading consequences, reaching beyond the sustainability of this fishery. By effectively dispersing seeds of >100 species, tambaqui plays a major role in the natural regeneration of Amazonian floodplain forests
We compared the vegetation structure between old (>70 year) stands of planted diversified native forests and stands of Eucalyptus tereticornis embedded in a mosaic of Eucalyptus stands. We then ...tested for differences in the abundance, species richness, species composition, and ecological traits (forest dependence, sensitivity to forest fragmentation, and diet) of the understory bird assemblages inhabiting both kinds of stands. We expected differences in the structure of the bird assemblages because of the different origins and management strategies (contrary to native stands, Eucalyptus stands were selectively logged in the past). Three stands of each habitat (native and Eucalyptus) were sampled with mist nets during 11 months. Eucalyptus stands had a denser understory, whereas native plantations had a more developed vertical structure and a greater density of native trees. The abundance distribution of bird species was more homogeneous in Eucalyptus than in native stands. Eucalyptus had slightly higher species richness (36 species) than native stands (32 species). The composition of species and the occurrence of the diet, forest dependence, and sensitivity to forest fragmentation categories were similar between habitats. Some bird species (e.g. Turdus leucomelas), however, were more abundant in one habitat over the other. Old stands of Eucalyptus and planted native forest can harbor a diverse bird community similar in structure but not exactly equivalent for individual bird species. Planting native diversified forests and keeping set‐aside stands of the exotic tree should be viewed as complementary rather than alternative strategies for maintaining bird diversity within plantations.
The large flood pulse of the Amazon basin is a principal driver of environmental heterogeneity with important implications for ecosystem function and the assembly of natural communities. ...Understanding species ecological response to the flood pulse is thus a key question with implications for theories of species coexistence, resource management, and conservation. Yet these remain largely undescribed for most species, and in particular for trees. The large flood pulse and high tree diversity of the Negro River floodplain makes it an ideal system to begin filling this knowledge gap. We merged historical hydrologic data with 41 forest inventories under variable flooding conditions distributed across the Negro River basin, comprising a total area of 34 ha, to (i) assess the importance of flood duration as a driver of compositional variation, (ii) model the response curve shapes of 111 of the most frequent tree species in function of flood duration, and (iii) derive their niche properties (optima and tolerance). We found that flood duration is a strong driver of compositional turnover, although the majority site-to-site variation in forest composition still remains unexplained. About 73% of species responded to the flood duration gradient, exhibiting a diversity of shapes, but most frequently skewed. About 29% of species were clearly favored by flood durations >120 days year
–1
, and 44% of species favored by shorter floods. The median niche breadth was 85 flood days year
–1
, corresponding to approximately 30% of the flood duration gradient. A significant subset of species (27%) did not respond to flooding, but rather exhibited wide tolerance to the flood gradient. The response models provided here offer valuable information regarding tree species differential capacity to grow, survive, and regenerate along an ecologically important gradient and are spatially valid for the Amazon Negro basin. These attributes make them an appealing tool with wide applicability for field and experimental studies in the region, as well as for vegetation monitoring and simulation models of floodplain forest change in the face of hydrologic alteration.
As florestas de várzea estão sendo afetadas ao longo de séculos por diversas atividades antrópicas que põem em risco a integridade desse ecossistema, demandando estudos que propiciem sua conservação ...e restauração. O objetivo deste estudo foi caracterizar a morfologia de plântulas de três espécies pioneiras presentes na floresta de várzea do lago Catalão - AM: Cecropia latiloba Miq. (Urticaceae), Ficus insipida Willd. (Moraceae) e Allophylus amazonicus (Mart.) Radlk. (Sapindaceae) como subsídio para criar ferramentas para sua identificação em campo. Para cada espécie foram coletadas sementes de três diferentes matrizes, as quais foram processadas e acondicionadas em bandejas para germinação em solo proveniente do local de coleta. Foram analisadas e descritas morfologicamente cada fase de desenvolvimento até a formação de plântulas e mudas. Nas três espécies, a germinação foi classificada como epígea e fanerocotiledonar, e todas apresentaram diferenças morfológicas nos cotilédones, eófilos e catáfilos, permitindo a separação visual das mesmas. Os resultados indicam que a morfologia foliar é uma importante ferramenta para auxiliar a identificação e diferenciação desde as fases iniciais do desenvolvimento das plântulas. Esse conhecimento pode subsidiar estratégias de manejo como a formação de banco de plântulas para a recuperação de áreas degradadas de várzea.
As florestas de várzea estão sendo afetadas ao longo de séculos por diversas atividades antrópicas que põem em risco a integridade desse ecossistema, demandando estudos que propiciem sua conservação ...e restauração. O objetivo deste estudo foi caracterizar a morfologia de plântulas de três espécies pioneiras presentes na floresta de várzea do lago Catalão - AM: Cecropia latiloba Miq. (Urticaceae), Ficus insipida Willd. (Moraceae) e Allophylus amazonicus (Mart.) Radlk. (Sapindaceae) como subsídio para criar ferramentas para sua identificação em campo. Para cada espécie foram coletadas sementes de três diferentes matrizes, as quais foram processadas e acondicionadas em bandejas para germinação em solo proveniente do local de coleta. Foram analisadas e descritas morfologicamente cada fase de desenvolvimento até a formação de plântulas e mudas. Nas três espécies, a germinação foi classificada como epígea e fanerocotiledonar, e todas apresentaram diferenças morfológicas nos cotilédones, eófilos e catáfilos, permitindo a separação visual das mesmas. Os resultados indicam que a morfologia foliar é uma importante ferramenta para auxiliar a identificação e diferenciação desde as fases iniciais do desenvolvimento das plântulas. Esse conhecimento pode subsidiar estratégias de manejo como a formação de banco de plântulas para a recuperação de áreas degradadas de várzea. Palavras-chave: Floresta alagável; Estabelecimento; Germinação; Ecologia morfofuncional; Sucessão florestal The white-water floodplain forests (várzea) have been affected for centuries by various human activities that endanger the integrity of this ecosystem, demanding studies that provide conservation and restoration. The objective of this study was to characterize the seedling morphology of three pioneer species present in the floodplain forest of Catalão Lake - AM: Cecropia latiloba Miq. (Urticaceae), Ficus insipida Willd. (Moraceae), Allophylus amazonicus (Mart.) Radlk. (Sapindaceae), as a subsidy to create tools for the field identification. Seeds were collected from three different matrices, these were processed and placed in trays for germination in soil from the collection site. Each developmental phase until the seedling formation was analyzed and morphologically described. In the three species, the germination was classified as epigeal and phanerocotyledonous, and all showed morphological differences in cotyledons, eophylls and cataphylls, allowing the visual separation of them. Our results indicate that the leaf morphology is an important tool to help the identification and differentiation from the early stages of the seedling development. This knowledge can support management strategies such as the formation of a seedling bank for the recovery of degraded várzea forests areas. Keywords: Floodplain forest; Establishment; Germination; Morphofunctional ecology; Forest succession
As herbáceas aquáticas são indicadoras da composição nutricional dos corpos de águaamazônicos e de suas áreas alagáveis, pois sua riqueza e abundância refletem as características físicas e químicas ...da bacia onde estão inseridas. Elas possuem diversas funções ecológicas, como proporcionar abrigo e alimento para organismos aquáticos e terrestres. Neste estudo, foi analisada a riqueza, diversidade e composição de espécies de herbáceas aquáticas e sua distribuição em nove igapós de água preta na Amazônia brasileira, dentro e fora de unidades de conservação (UCs). Os resultados foram obtidos por meio de inventários realizados entre os anos de 2009 e 2017, nos rios Negro, Jaú, Aracá, Cuiuni, Uatumã e Abacate. Foram amostradas 148 parcelas retangulares de 100 x 1m, distribuídas em nove pontos amostrais (6 a 29 parcelas por ponto). O levantamento florístico revelou 174 espécies, distribuídas em 99 gêneros e 46 famílias botânicas, predominando as famílias Cyperaceae (43 ssp.), Poaceae (33 ssp.) e Marantaceae (10 ssp.). As áreas apresentaram baixa similaridade florística, sendo que nenhuma espécie ocorreu em todas as áreas amostradas. As espécies Montrichardia arborescens (L.) Schott (Araceae) e Scleria secans (L.) Urb (Cyperaceae) foram as mais frequentes, ocorrendo em seis das nove áreas amostradas. Apenas 49,2% das espécies de herbáceas aquáticas amostradas estão presentes nas UCs inventariadas, indicando que estratégias de conservação que envolvam mais áreas de igapó de águas pretas precisam ser consideradas para a proteção desse importante grupo de plantas.
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