Understanding species richness–productivity relationships: the importance of meta-analyses

Ecology ◽  
2010 ◽  
Vol 91 (9) ◽  
pp. 2540-2544 ◽  
Author(s):  
Gary G. Mittelbach
2018 ◽  
Vol 34 (2) ◽  
pp. 75-92 ◽  
Author(s):  
Ryan C. Burner ◽  
Alison R. Styring ◽  
Chandradewana Boer ◽  
Frederick H. Sheldon

Abstract:Altitudinal gradients provide tractable, replicated systems in which to study changes in species richness and community composition over relatively short distances. Previously, richness was often assumed to follow a monotonic decline with altitude, but recent meta-analyses show that more complex patterns, including mid-altitude richness peaks, are also prevalent in birds. In this study, we used point counts to survey birds at multiple altitudes on three mountains on the island of Borneo in Sundaland, an area for which quantitative analyses of avian altitudinal distribution are unavailable. In total we conducted 1088 point counts and collected associated habitat data at 527 locations to estimate species richness by altitude on Mt Mulu (2376 m), Mt Pueh (1550 m) and Mt Topap Oso (1450 m). On Mulu, the only mountain with an intact habitat gradient, bird species richness peaks at 600 m. Richness appeared to peak at 600 m on Totap Oso as well, but on Pueh it peaked several hundred metres higher. The richness peak on Mulu differs from that predicted by null models and is instead caused by the overlap of distinct lowland and montane avifaunas, supporting the faunal overlap hypothesis. This finding provides further evidence that a lack of coincidence between peak turnover and peak richness is not sufficient evidence to rule out faunal overlap as a causal factor.


2019 ◽  
pp. 38-60
Author(s):  
Gary G. Mittelbach ◽  
Brian J. McGill

This chapter examines the relationship between biodiversity (most often measured as species richness) and the functioning of ecosystems. Examined in detail are the effects of biodiversity on: ecosystem productivity, nutrient use and nutrient retention, community and ecosystem stability, and invasibility by exotic species. A careful look, over two decades, at experimental results and meta-analyses confirms the positive impact of species richness on productivity, ecosystem stability, and nutrient retention. Thus, we can confidently conclude that biodiversity matters to the healthy functioning of ecosystems, although we do not yet know how many species are needed to ensure the successful functioning of any given ecosystem. The chapter concludes with a discussion of six important, but unanswered question in the study of biodiversity and ecosystem functioning.


2021 ◽  
Vol 41 (6) ◽  
Author(s):  
Francesca Piseddu ◽  
Gianni Bellocchi ◽  
Catherine Picon-Cochard

2021 ◽  
Author(s):  
David YP Tng ◽  
Deborah MG Apgaua ◽  
Nicholas J Fisher ◽  
Victor W Fazio

Diversity studies on moths in Australia are rare, presenting various shortfalls in knowledge that impedes and understanding of their biodiversity values and their conservation. In particular, the Wet Tropics of Australia deserves attention, given the paucity of systematic moth surveys in the region and its World Heritage Area status. To fill this knowledge gap, we conducted a study to observe moths on 191 nights over a main one-year survey period at an upland rainforest locality, and uploaded all observations on iNaturalist. We also compiled other incidental observations in the general locality by other observers and observations outside the survey period. In total, we document 4,434 observations of moths represented by 1041 distinct moth morphospecies. Of these, 703 are formally named species of moths, 146 to genus and 255 to higher taxonomic designations above genus level. Despite the rather intensive main survey effort, our results suggest that we have yet to reach a plateau in documenting the moth species richness of the locality. Using this study as a model, we show that the iNaturalist platform serves as an effective means to document and digitally curate biodiversity values at a locality, whilst providing complete data transparency and enabling broader community engagement of citizen scientists. We recommend the use of iNaturalist for future moth inventories, and as a resource for follow up meta-analyses of regional moth diversity and distributions.


2019 ◽  
Vol 2 ◽  
Author(s):  
Pavel Saska

Meta-analysis represents an approach of synthesizing many independent data sets, and is useful in situations when abundant literature provides no conclusive evidence. Besides the quality of the research itself, the value of an individual study for meta-analysis depends to the large extent also on the quality of data presentation. The literature based on carabid beetles (Coleoptera: Carabidae) as the study is enormous, therefore there is a great potential for the use in meta-analyses. In this paper I put together some notes which arose during my work on meta-analysis focused on the effects of field and crop management on populations of carabid beetles inside the crop fields of Europe and America north of Mexico. The aim of this contribution is to provide a set of recommendations which may potentially improve the use of each individual paper in future meta-analyses, and thus increase the impact of the original paper as well as the generality of conclusions drawn from future meta-analyses, hence based on larger sample size. Be accurate in describing the treatments. For example, “low” and “high intensity of management” is not enough. Mention also details that are constant across treatments, but may still provide useful information. E.g. “practice usual for the area” is not enough. Be precise with describing spatio-temporal structure in the study. Provide redundant information so everyone can check if he/she understood well the hierarchy of the experiment and the number of replications associated with each stratum. A scheme may be useful. Report the grand totals as well as treatment totals for both “abundance” and species richness. Text, tables or supplementary materials is preferred. If using mean values, always make it clear what is the number of replicates and provide standard errors. But, remember that total or treatment species richness cannot be reconstructed from the mean! Be explicit in stating what the means represent, also in figures. Expressions like “Mean abundance” are not enough. Provide species lists with the greatest resolution possible. Most journals allow for supplementary materials where this information can be provided. Remember that data can also be extracted from figures. Provide high resolution and accurate figures. For example, large data points on a line make data extraction difficult. Be accurate in describing the treatments. For example, “low” and “high intensity of management” is not enough. Mention also details that are constant across treatments, but may still provide useful information. E.g. “practice usual for the area” is not enough. Be precise with describing spatio-temporal structure in the study. Provide redundant information so everyone can check if he/she understood well the hierarchy of the experiment and the number of replications associated with each stratum. A scheme may be useful. Report the grand totals as well as treatment totals for both “abundance” and species richness. Text, tables or supplementary materials is preferred. If using mean values, always make it clear what is the number of replicates and provide standard errors. But, remember that total or treatment species richness cannot be reconstructed from the mean! Be explicit in stating what the means represent, also in figures. Expressions like “Mean abundance” are not enough. Provide species lists with the greatest resolution possible. Most journals allow for supplementary materials where this information can be provided. Remember that data can also be extracted from figures. Provide high resolution and accurate figures. For example, large data points on a line make data extraction difficult. With little extra effort during the preparation phase, the impact of your paper and the use of your data may considerably increase in the future.


2011 ◽  
Vol 6 (4) ◽  
pp. 58
Author(s):  
JANE ANDERSON
Keyword(s):  

VASA ◽  
2017 ◽  
Vol 46 (3) ◽  
pp. 151-158 ◽  
Author(s):  
Hisato Takagi ◽  
Takuya Umemoto

Abstract. Both coronary and peripheral artery disease are representative atherosclerotic diseases, which are also known to be positively associated with presence of abdominal aortic aneurysm. It is still controversial, however, whether coronary and peripheral artery disease are positively associated with expansion and rupture as well as presence of abdominal aortic aneurysm. In the present article, we overviewed epidemiological evidence, i. e. meta-analyses, regarding the associations of coronary and peripheral artery disease with presence, expansion, and rupture of abdominal aortic aneurysm through a systematic literature search. Our exhaustive search identified seven meta-analyses, which suggest that both coronary and peripheral artery disease are positively associated with presence of abdominal aortic aneurysm, may be negatively associated with expansion of abdominal aortic aneurysm, and might be unassociated with rupture of abdominal aortic aneurysm.


VASA ◽  
2018 ◽  
Vol 47 (4) ◽  
pp. 273-277
Author(s):  
Christopher Lowe ◽  
Oussama El Bakbachi ◽  
Damian Kelleher ◽  
Imran Asghar ◽  
Francesco Torella ◽  
...  

Abstract. The aim of this review was to investigate presentation, aetiology, management, and outcomes of bowel ischaemia following EVAR. We present a case report and searched electronic bibliographic databases to identify published reports of bowel ischaemia following elective infra-renal EVAR not involving hypogastric artery coverage or iliac branch devices. We conducted our review according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement standards. In total, five cohort studies and three case reports were included. These studies detailed some 6,184 infra-renal elective EVARs, without procedure-related occlusion of the hypogastric arteries, performed between 1996 and 2014. Bowel ischaemia in this setting is uncommon with an incidence ranging from 0.5 to 2.8 % and includes a spectrum of severity from mucosal to transmural ischaemia. Due to varying reporting standards, an overall proportion of patients requiring bowel resection could not be ascertained. In the larger series, mortality ranged from 35 to 80 %. Atheroembolization, hypotension, and inferior mesenteric artery occlusion were reported as potential causative factors. Elderly patients and those undergoing prolonged procedures appear at higher risk. Bowel ischaemia is a rare but potentially devastating complication following elective infra-renal EVAR and can occur in the setting of patent mesenteric vessels and hypogastric arteries. Mortality ranges from 35 to 80 %. Further research is required to identify risk factors and establish prophylactic measures in patients that have an increased risk of developing bowel ischaemia after standard infra-renal EVAR.


Crisis ◽  
2020 ◽  
pp. 1-5
Author(s):  
Shannon Lange ◽  
Courtney Bagge ◽  
Charlotte Probst ◽  
Jürgen Rehm

Abstract. Background: In recent years, the rate of death by suicide has been increasing disproportionately among females and young adults in the United States. Presumably this trend has been mirrored by the proportion of individuals with suicidal ideation who attempted suicide. Aim: We aimed to investigate whether the proportion of individuals in the United States with suicidal ideation who attempted suicide differed by age and/or sex, and whether this proportion has increased over time. Method: Individual-level data from the National Survey on Drug Use and Health (NSDUH), 2008–2017, were used to estimate the year-, age category-, and sex-specific proportion of individuals with past-year suicidal ideation who attempted suicide. We then determined whether this proportion differed by age category, sex, and across years using random-effects meta-regression. Overall, age category- and sex-specific proportions across survey years were estimated using random-effects meta-analyses. Results: Although the proportion was found to be significantly higher among females and those aged 18–25 years, it had not significantly increased over the past 10 years. Limitations: Data were self-reported and restricted to past-year suicidal ideation and suicide attempts. Conclusion: The increase in the death by suicide rate in the United States over the past 10 years was not mirrored by the proportion of individuals with past-year suicidal ideation who attempted suicide during this period.


Sign in / Sign up

Export Citation Format

Share Document