Recently, ecological niche models have been employed to investigate the potential geographical distribution of species. However, it is necessary to analyze the vast number of publications on this topic to understand the trends and biases of research using ecological niche models (ENMs). Therefore, this study aims to investigate trends in the scientific literature regarding studies on ENMs. For the quantitative analysis of the literature on ENMs, we performed a search in the Thomson ISI (Web of Science) database between 1991 and 2013. The search identified 3042 papers containing preselected keywords in either the title or abstract. The results showed that the number of papers has increased over the years (r=0.77, P<0.001), with a sharp increase in recent years, highlighting the widespread use of the ENMs. There was an increase in the diversity of journals that published papers about ENMs (r=0.97, P<0.001). The research was conducted in different countries, predominantly the United States of America (550 papers), and the most commonly used method was the Maximum Entropy method (312 papers). Regarding the taxonomic group, most research has been conducted on plants (402 papers, or 28.36% of the total). There was no relationship between the modeling method used and the taxonomic group studied (χ 2 =4.8, P=0.15). Finally, the wide availability of biological, environmental and computational resources has elicited the broad use of tools for ENMs. Despite the conceptual discussions of the ENMs, this method is currently the most effective way to evaluate the potential geographical distribution of species, and to predict the distribution under different environmental conditions (i.e., future or past scenarios).Keywords: scientometric, species distribution model, Maximum Entropy. Tendências e vieses na literatura científica mundial sobre modelos de nicho ecológico ResumoRecentemente, modelos de nicho têm sido empregados para investigar a distribuição geográfica potencial de espécies. Porém, é necessário analisar a vasta quantidade de publicações sobre o referido tema, a fim de compreender as tendências e vieses das pesquisas que usam modelos de nicho ecológico (MNEs). Portanto, esse trabalho tem por objetivo investigar as tendências da literatura científica de trabalhos sobre MNEs. Para a análise quantitativa das publicações sobre MNEs, foi realizada uma busca na base de dados Thomson ISI (Web of Science), entre o período de 1991 a 2013. A pesquisa agrupou 3042 documentos que continham nas palavras-chave, no título ou no resumo os termos selecionados para a busca. Os resultados mostraram que de forma geral o número de artigos tem aumentado ao longo dos anos (r=0,77, P<0,001), com um acentuado crescimento nos anos mais recentes, destacando o amplo uso de MNEs. Ao longo dos anos percebeu-se um aumento da diversidade de revistas que publicam sobre o assunto (r=0,97, P<0,001). As pesquisas têm sido desenvolvidas em diferentes países, com predomínio dos Estados Unidos (550 artigos) e o método mais utilizado foi o de Máxi...

The Cerrado (Brazilian savanna) is the second largest Brazilian biome and is considered a biodiversity hotspot, for presenting high endemism and being under intense threat. This study aimed at highlighting publication trends on the Cerrado, detecting possible gaps and indicating future directions for scientific studies on this biome. We searched for articles between 1991 and 2012 in the journal database of the Institute for Scientific Information (ISI). We observed a significant increase in the number of articles throughout the years of the evaluated period (r=0.89; P<0.001), demonstrating an increasing interest of the scientific community in the Cerrado. Largely addressed issues were related to biodiversity (64.75%), followed by abiotic environment (13.38%) and agricultural crops (11.21%). In addition, 10.65% addressed both biodiversity and abiotic environment jointly. The most studied taxonomic group was plants (42%), followed by fungi (18%) and insects (12%). Fishes presented a lower number of studies (0.6%). The main gaps concern the few studies dealing with abiotic aspects and freshwater organisms, such as fishes, and also a low increment in the number of articles on invertebrates, except insects. Based on these gaps, we suggest that future studies must be especially directed towards aquatic environments and their biodiversity.

We assess the impact of climate change on the geographic distribution and productivity of Euterpe oleracea (Arecaceae), commonly called açaí. To construct the ecological niche model of E. oleracea, we used 95 points of occurrence, fi ve bioclimatic variables in current and future climate scenarios and Maxent software. Th e Akaike Information Criteria (AIC) was used to rank the ability of the models (considering ecological, socioeconomic and spatial variables) to explain the variation in productivity of E. oleracea among 200 municipalities. Th e maps showed that regions with higher environmental suitability for E. oleracea were concentrated in northern and northeastern Brazil, which was similar to the spatial pattern of productivity data of E. oleracea. Future climate conditions tend to promote an increase in the geographical distribution of this species, even though the new regions are in the arch of Amazon deforestation. Only space and the environmental suitability (indicated by the ecological niche model) were important for explaining the productivity of E. oleracea. Th at is, municipalities that are more productive are located in more suitable environmental regions. Th erefore, it is important to use niche models to explain demographic changes and to estimate species demographic attributes.

Palavras-chave:Physalis pubescens, altura da planta, produtividade. ABSTRACTPlant growth and production of husk tomato depending on organic fertilization and mulching A field trial was carried out in Ipameri, State of Goias, Brazil, to study the effect of residual cattle manure and soil covering on plant growth and yield of husk tomato. Sowing was carried out in October 01, and seedlings were kept under greenhouse with 50% of shadow, until planting in the field in November 11, 2007, after tomato crop. The experimental design was randomized block with split-plot scheme with three replications. Cattle manure treatments were applied to the plots (30 and 60 t ha -1 ) and soil covering to subplots (black plastic, Brachiaria grass and without covering). The sub plot consisted of 20 plants arranged at space of 1.00 x 0.30 m. Black plastic covering favored plant growth and yield. Minor effects were obtained with residual cattle manure. Plant height followed cubic regression model.