Sensitivity of mangrove range limits to climate variability

Aim: Correlative distribution models have been used to identify potential climatic controls of mangrove range limits, but there is still uncertainty about the relative importance of these factors across different regions. To provide insights into the strength of climatic control of different mangrove range limits, we tested whether temporal variability in mangrove abundance increases near range limits and whether this variability is correlated with climatic factors thought to control large scale mangrove distributions. Location: North and South America. Time period: 1984–2011. Major taxa studied: Avicennia germinans, Avicennia schuaeriana, Rhizophora mangle, Laguncularia racemosa. Methods: We characterized temporal variability in the enhanced vegetation index (EVI) at mangrove range limits using Landsat satellite imagery collected between 1984–2011. We characterized greening trends at each range limit, examined variability in EVI along latitudinal gradients near each range limit, and assessed correlations between changes in EVI and temperature and precipitation. Results: Spatial variability in mean EVI was generally correlated with temperature and precipitation, but the relationships were region specific. Greening trends were most pronounced at range limits in eastern North America. In these regions variability in EVI increased toward the range limit and was sensitive to climatic factors. In contrast, EVI at range limits on the Pacific coast of North America and both coasts of South America was relatively stable and less sensitive to climatic variability. Main conclusions: Our results suggest that range limits in eastern North America are strongly controlled by climate factors. Mangrove expansion in response to future warming is expected to be rapid in regions that are highly sensitive to climate variability (e.g. eastern North America), but the response in other range limits (e.g. South America) is likely to be more complex and modulated by additional factors such as dispersal limitation, habitat constraints, and/or changing climatic means rather than just extremes

Red de reservas marinas para la Región de las Grandes Islas, Golfo de California: protocolo del proyecto de planeación y reporte de los talleres del equipo de planeación [Marine reserves network for the Midriff Islands Region, Gulf of California, Mexico: planning protocol and progress report to the WWF Mexico & Carlos Slim Foundation Alliance]

La Región de las Grandes Islas (RGI), localizada en el acuario del mundo, el Golfo de California, es reconocida a nivel mundial por su espectacular belleza, diversidad y productividad; en ocasiones se le ha denominada como "las Galápagos del Hemisferio Norte" (Figura 1). En sus 45 islas, incluyendo las dos más grandes de México, Tiburón e Isla Ángel de la Guarda, se han registrado más de 400 especies de plantas, anfibios, reptiles y mamíferos terrestres, algunas de ellas endémicas a una o varias de las islas. En algunas de estas islas, como Rasa y San Pedro Mártir, llegan a anidar cientos de miles de aves marinas. Alrededor de este gran archipiélago, se pueden observar hasta 23 especies de mamíferos marinos, incluyendo la súper agregación de cachalotes en la cuenca San Pedro Mártir. Así como también es un sitio usado por cinco especies de tortugas marinas para hibernar y alimentarse. [English] In collaboration with researchers, agencies and NGOs, we aim to guide the design and implementation of a network of marine reserves for Midriff Islands, Gulf of California, a marine conservation hotspot. The area is one of the most important fishing regions in Mexico and livelihoods of coastal communities are threatened by depletion of fish stocks and climate change. The project aims to develop a practical approach to design networks of marine reserves that consider ecological connectivity and the effects of climate change. The project is an example of interdisciplinary and collaborative applied research, including over 25 researchers and managers from NGOs (COBI, Pronatura), universities (James Cook University, The University of Queensland, Arizona State University, SCRIPPS, The University of Arizona), and national (Mexico’s Commissions for Protected Areas and Biodiversity) and international agencies (NOAA)

Goodbye Hartmann trial: a prospective, international, multicenter, observational study on the current use of a surgical procedure developed a century ago

Background: Literature suggests colonic resection and primary anastomosis (RPA) instead of Hartmann's procedure (HP) for the treatment of left-sided colonic emergencies. We aim to evaluate the surgical options globally used to treat patients with acute left-sided colonic emergencies and the factors that leading to the choice of treatment, comparing HP and RPA. Methods: This is a prospective, international, multicenter, observational study registered on ClinicalTrials.gov. A total 1215 patients with left-sided colonic emergencies who required surgery were included from 204 centers during the period of March 1, 2020, to May 31, 2020. with a 1-year follow-up. Results: 564 patients (43.1%) were females. The mean age was 65.9 ± 15.6 years. HP was performed in 697 (57.3%) patients and RPA in 384 (31.6%) cases. Complicated acute diverticulitis was the most common cause of left-sided colonic emergencies (40.2%), followed by colorectal malignancy (36.6%). Severe complications (Clavien-Dindo ≥ 3b) were higher in the HP group (P < 0.001). 30-day mortality was higher in HP patients (13.7%), especially in case of bowel perforation and diffused peritonitis. 1-year follow-up showed no differences on ostomy reversal rate between HP and RPA. (P = 0.127). A backward likelihood logistic regression model showed that RPA was preferred in younger patients, having low ASA score (≤ 3), in case of large bowel obstruction, absence of colonic ischemia, longer time from admission to surgery, operating early at the day working hours, by a surgeon who performed more than 50 colorectal resections. Conclusions: After 100 years since the first Hartmann's procedure, HP remains the most common treatment for left-sided colorectal emergencies. Treatment's choice depends on patient characteristics, the time of surgery and the experience of the surgeon. RPA should be considered as the gold standard for surgery, with HP being an exception