ABSTRACT Agricultural matrices can lead to landscape homogenization, culminating in losses of biodiversity and ecosystem services. Agricultural management is determinant for developing conservation strategies. In this review, we discuss the influence of the agricultural matrix on biodiversity at different scales. Intensive agriculture under agrochemicals and synthetic fertilizers aggravates forest fragmentation processes, compromising conservation habitats. On the other hand, managed matrixes with greater agricultural biodiversity and reduced synthetic inputs tend to favor species’ persistence. There is discord regarding the best model to conserve biodiversity in agricultural landscapes, but the land sharing system increases the landscape heterogeneity, ensures food production, and constitutes a safer approach from the socioecological perspective. Future studies should consider the matrix identity and management to assess fragmentation effects and its ability to harbor biodiversity.

Spatial pattern of the palm Astrocaryum aculeatissimum was investigated in an urban Atlantic Forest fragment (Tijuca National Park, Brazil) where its main seed disperser, the red-rumped agouti Dasyprocta leporina, is locally extinct. A 120 × 130 m plot (1.56 ha) was established in which all A. aculeatissimum individuals were quantified, georeferenced, and classified by ontogenetic stages, namely, seedling, infant, juvenile, immature individual, and adult. Analyses were performed using Ripley's K function. We recorded 376 individuals, most of which were in the juvenile stage (n = 228). The spatial pattern was aggregated as observed for other palm species. Seedlings and infants were not associated with adults, whereas juveniles and immature individuals were observed closer to adults than expected. The distance between each seedling and the nearest adult ranged from 3 to 30 m (mean ± sd = 11.8 ± 7.8), which is similar to the agouti dispersal distances reported in other studies. Despite the importance of agoutis for the seedling recruitment of A. aculeatissimum, their short-term absence does not affect the spatial distribution of this palm in the studied area.

Here, we investigated the population structure of the exotic palm Roystonea oleracea in a swamp on an island within the Atlantic Forest Biome, evaluating its influence on the seedling recruitment of other plant species. The population structure was analyzed in six 4 × 30 m plots, within which we categorized all individuals by ontogenetic stage. The influence of R. oleracea on the seedling recruitment of other plant species was evaluated in 2 × 2 m plots established beneath palm crowns and in adjacent areas without palms. We recorded 53 R. oleracea individuals. The majority (56.6%) of the R. oleracea population was composed of immature adults, followed by mature adults. The density, richness and diversity of seedling species differed significantly between areas beneath and away from palms, the values being lower beneath R. oleracea crowns. Our results indicate that R. oleracea recruitment does not require human intervention, the number of reproductive individuals characterizing successful naturalization. This underscores the need for management policies aimed at palm eradication in order to avoid reductions in biodiversity.

Mamíferos de médio e grande porte desempenham funções importantes para a manutenção dos ecossistemas. Porém, esse grupo é um dos mais vulneráveis a extinções locais, seja pela perda de hábitat ou pela caça. Neste estudo foi inventariada a comunidade de médios e grandes mamíferos na Reserva Ecológica de Guapiaçú (REGUA), Cachoeiras de Macacu, RJ, sendo descritos dados de composição, riqueza e abundância. As espécies foram registradas através do uso de armadilhas fotográficas, busca por vestígios e visualizações diretas em trilhas e estradas pré-existentes. O estudo foi realizado de janeiro a outubro de 2012, sendo cada mês considerado uma unidade amostral. A partir de um esforço de 1568 câmeras-dia e de 120 km caminhados, obtivemos 302 registros de 22 espécies de mamíferos de médio e grande porte, pertencentes a oito Ordens. Esse valor corresponde a mais que três quartos da riqueza de espécies descrita para esse grupo na Mata Atlântica do estado do Rio de Janeiro. Cinco espécies encontram-se sob algum nível de ameaça regional, nacional ou global. Três espécies cinegéticas,Pecari tajacu, Cuniculus paca eDasyprocta leporina foram abundantes na área. A riqueza observada foi comparável è encontrada em outros estudos realizados em florestas ombrófilas densas. Assim, por seu elevado número de espécies, incluindo aquelas sob algum grau de ameaça, concluímos que a REGUA é um lugar de destaque para a conservação da biodiversidade de mamíferos, especialmente na Mata Atlântica do estado do Rio de Janeiro.

Medium and large-sized terrestrial mammals develop important functions in ecosystems maintenance. However, this group is the most vulnerable to local extinctions, through habitat loss or hunting. This study inventoried the community of medium and large mammals in the Reserva Ecológica de Guapiaçú (REGUA), Cachoeiras de Macacu, RJ, providing data on species composition, richness and abundance. Species were registered through the use of camera traps, sign survey and visual encounters on pre-existing trails and roads. The study was conducted from January to October 2012, with each month considered as a sample unit. An effort of 1568 cameras-day and 120 km traveled, resulted on 302 records of 22 species of medium and large-sized mammals, belonging to eight orders. This value corresponds to more than three-quarters of the richness described from this group in the Atlantic Forest of Rio de Janeiro state. Five species are under some level of regional, national or global threat. Three game species, Pecari tajacu, Cuniculus paca and Dasyprocta leporina were abundant in the area. The observed richness was comparable to that found in other studies conducted in rain forests. Thus, for its high number of species, including those under some degree of threat, we conclude that REGUA is an important area to mammal conservation, especially in the Atlantic Forest of Rio de Janeiro state.

O desenvolvimento anormal de ramos ao longo do estipe de Euterpe edulis é descrito pela primeira vez. Os ramos se originaram a uma altura que variou de 2 a 190 cm do solo. Indivíduos ramificados e ramos foram capazes de produzir estruturas reprodutivas e alguns ramos produziram raízes. Uma possível causa para a anomalia observada seriam problemas genéticos decorrentes dos pequenos tamanhos populacionais. Um melhor entendimento desse processo pode ter um efeito positivo na extração do palmito dessa espécie através da indução artificial de brotos, evitando assim a morte do indivíduo.

The unusual development of branches along the stem of Euterpe edulis is described for the first time. Branches originated at 2 to 190 cm from the ground. Ramified individuals and branches were able to produce reproductive structures and some branches produced roots. A plausible cause for the observed anomaly could be genetic problems due to small population sizes. The better agreement of this process can have a positive effect in the harvest of the heart of palm through the artificial induction of sprouts, what would prevent the death of the individual.