Sea Urchins Predation Facilitates Coral Invasion in a Marine Reserve

Macroalgae is the dominant trophic group on Mediterranean infralittoral rocky bottoms, whereas zooxanthellate corals are extremely rare. However, in recent years, the invasive coral Oculina patagonica appears to be increasing its abundance through unknown means. Here we examine the pattern of variation of this species at a marine reserve between 2002 and 2010 and contribute to the understanding of the mechanisms that allow its current increase. Because indirect interactions between species can play a relevant role in the establishment of species, a parallel assessment of the sea urchin Paracentrotus lividus, the main herbivorous invertebrate in this habitat and thus a key species, was conducted. O. patagonica has shown a 3-fold increase in abundance over the last 8 years and has become the most abundant invertebrate in the shallow waters of the marine reserve, matching some dominant erect macroalgae in abundance. High recruitment played an important role in this increasing coral abundance. The results from this study provide compelling evidence that the increase in sea urchin abundance may be one of the main drivers of the observed increase in coral abundance. Sea urchins overgraze macroalgae and create barren patches in the space-limited macroalgal community that subsequently facilitate coral recruitment. This study indicates that trophic interactions contributed to the success of an invasive coral in the Mediterranean because sea urchins grazing activity indirectly facilitated expansion of the coral. Current coral abundance at the marine reserve has ended the monopolization of algae in rocky infralittoral assemblages, an event that could greatly modify both the underwater seascape and the sources of primary production in the ecosystem

Outcomes from elective colorectal cancer surgery during the SARS-CoV-2 pandemic

This study aimed to describe the change in surgical practice and the impact of SARS-CoV-2 on mortality after surgical resection of colorectal cancer during the initial phases of the SARS-CoV-2 pandemic

Controle químico de plantas daninhas com diferentes dosagens de herbicida a base de fluroxipir+picloram.

A pecuária é uma das principais atividades da economia brasileira e as pastagens assumem papel neste cenário. Entretanto, fatores externos como as plantas daninhas tendem a diminuir a produtividade, a lucratividade e a rentabilidade das propriedades rurais. Objetivou-se comparar a eficiência de controle de três diferentes dosagens de herbicida em uma área infestada predominantemente pelas espécies Mimosa debilis, Malva sylvestri, Kudzu lobata e Spermacoce latifolia com o intuito de saber quais dosagens seriam viáveis ao uso sem comprometer a eficiência do controle. O experimento foi realizado na Universidade Federal do Acre, entre os meses de maio a julho de 2018, em um delineamento inteiramente casualizado com 4 tratamentos e 5 repetições. Os tratamentos foram: T1: 0 ml dosagem/calda, T2 (100ml/20L): 25 ml dosagem/calda, T3 (200ml/20L): 50 ml dosagem/calda e T4 (300ml/20L): 75 ml dosagem/calda. As médias das populações de plantas daninhas foram comparadas pelo teste de Tukey (5%). O T2 controlou 13,2% de população e sua utilização não é viável. Entre os T3 e T4 não houve diferença estatística (p<0,05) obtendo-se 95, 4% e 98,2% de eficiência de controle, respectivamente. A utilização da dosagem 200ml/20L é a mais viável de ser utilizada, observando-se a taxa de controle adequada, diminuindo sua incidência e melhorando a produção das pastagens aliado ao fato da menor relação custo-benefício quando comparada com a dose de 300ml/20L do T4

Environmental Quality of Catalan Coastal Waters Based on Macroalgae: The Interannual Variability of CARLIT Index and Its Ability to Detect Changes in Anthropogenic Pressures over Time

CARLIT is a Water Framework Directive-compliant methodology permitting a rapid assessment of water quality using rocky-shore macroalgae as biological quality elements. Here we present the water quality assessment of 32 coastal water bodies of Catalonia (Northwestern Mediterranean) during a period of 14 years (1999–2012) applying CARLIT. The averaged ecological status of the water bodies ranges between high and poor and the Ecological Quality Ratio shows a significant negative relationship with a modified LUSI index, thus providing further evidence on the utility of CARLIT to detect anthropogenic pressures. The lowest interannual variability in water quality was found in water bodies having most of their shore covered by natural rocks, while the highest variability was observed in water bodies situated in semi-confined environments or located close to freshwater discharges. In spite of the multiple advantages of CARLIT as a monitoring methodology, it can show strong disagreements in water quality assessment with other methodologies using other biological quality elements (i.e., macroinvertebrates). These discrepancies mainly occur in water bodies with reduced extension of rocky shores, questioning the use of CARLIT in these situations.Peer reviewe