Integrating community assembly and biodiversity to better understand ecosystem function: the Community Assembly and the Functioning of Ecosystems (CAFE) approach.

The research of a generation of ecologists was catalysed by the recognition that the number and identity of species in communities influences the functioning of ecosystems. The relationship between biodiversity and ecosystem functioning (BEF) is most often examined by controlling species richness and randomising community composition. In natural systems, biodiversity changes are often part of a bigger community assembly dynamic. Therefore, focusing on community assembly and the functioning of ecosystems (CAFE), by integrating both species richness and composition through species gains, losses and changes in abundance, will better reveal how community changes affect ecosystem function. We synthesise the BEF and CAFE perspectives using an ecological application of the Price equation, which partitions the contributions of richness and composition to function. Using empirical examples, we show how the CAFE approach reveals important contributions of composition to function. These examples show how changes in species richness and composition driven by environmental perturbations can work in concert or antagonistically to influence ecosystem function. Considering how communities change in an integrative fashion, rather than focusing on one axis of community structure at a time, will improve our ability to anticipate and predict changes in ecosystem function

Acute appendicitis revealed by an abscess of the anterior abdominal wall: A case report

Introduction: Appendicitis is a common cause of acute abdomen; however the classic clinical signs are not often present, which can be manifested by numerous complications, but the revelation by a parietal collection remains unusual, its diagnosis can be challenging.&nbsp;Presentation of case: We describe the case of a 31 years old man, who complains for pain of the right flank. The clinical examination objective an erythematous and painful swelling of the right iliac fossa, the abdominal ultrasound has objectified a collection of the right flank and right iliac fossa, The CT Scan of the Abdomen/Pelvis found a voluminous collection of soft tissues of the right anterolateral abdominal and pelvic wall, hypo dense and heterogeneous, containing air, The surgical exploration objectified a huge purulent collection with subcutaneously ceacum and appendage suppurated and perforated.Conclusion: The onset of an abdominal wall abscess without a known cause needs to be thoroughly investigated, with consideration of a subjacent abdominal cause and appendicitis.</p

A cross-scale assessment of productivity–diversity relationships

Aim: Biodiversity and ecosystem productivity vary across the globe, and considerable effort has been made to describe their relationships. Biodiversity and ecosystem functioning research has traditionally focused on how experimentally controlled species richness affects net primary productivity (S → NPP) at small spatial grains. In contrast, the influence of productivity on richness (NPP → S) has been explored at many grains in naturally assembled communities. Mismatches in spatial scale between approaches have fuelled debate about the strength and direction of biodiversity–productivity relationships. Here, we examine the direction and strength of the influence of productivity on diversity (NPP → S) and the influence of diversity on productivity (S → NPP) and how these vary across spatial grains. Location: Contiguous USA. Time period: 1999–2015. Major taxa studied: Woody species (angiosperms and gymnosperms). Methods: Using data from North American forests at grains from local (672 m2) to coarse spatial units (median area = 35,677 km2), we assess relationships between diversity and productivity using structural equation and random forest models, while accounting for variation in climate, environmental heterogeneity, management and forest age. Results: We show that relationships between S and NPP strengthen with spatial grain. Within each grain, S → NPP and NPP → S have similar magnitudes, meaning that processes underlying S → NPP and NPP → S either operate simultaneously or that one of them is real and the other is an artefact. At all spatial grains, S was one of the weakest predictors of forest productivity, which was largely driven by biomass, temperature and forest management and age. Main conclusions: We conclude that spatial grain mediates relationships between biodiversity and productivity in real-world ecosystems and that results supporting predictions from each approach (NPP → S and S → NPP) serve as an impetus for future studies testing underlying mechanisms. Productivity–diversity relationships emerge at multiple spatial grains, which should widen the focus of national and global policy and research to larger spatial grains.</p

Data for "Integrating community assembly and biodiversity reveals new dimensions of ecosystem function: the Community Assembly and the Functioning of Ecosystems (CAFE) approach"

Data supporting the Ecology Letters publication entitled "Integrating community assembly and biodiversity to better understand ecosystem function: the Community Assembly and the Functioning of Ecosystems (CAFE) approach". <p><b></b></p><div><br></div><div>3 files are provided for the three case studies included in the paper. </div><div>1. Flory and Clay 2010</div><div>2. Casas et al. 2004</div><div>3. Thibault and Brown 2008</div><div><br></div><div>[R] code is available at <a href="https://github.com/ctkremer/priceTools">https://github.com/ctkremer/priceTools</a>. </div