diversity effect
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Author(s):  
Sıla Öcalan-Özel ◽  
Patrick Llerena

This paper explores the relationship between the industry collaborations of grant applicant teams and the outcomes of a multistage grant evaluation process. We studied this relationship by focusing on two possible channels of impact of industry engagement—team diversity (or the diversity effect) and prior collaboration experience (or the experience effect)—and examined their influence on the evaluators' decision by using the proxies of direct industry engagement (i.e., the involvement of a company-affiliated researcher in the grant applicant team) and indirect industry engagement (i.e., joint publications with a company-affiliated researcher prior to the grant application), respectively. We analyzed data extracted from the application and reviewed materials of a multidisciplinary, pan-European research funding scheme—European Collaborative Research (EUROCORES)—for the period 2002–2010 and conducted an empirical investigation of its three consecutive grant evaluation stages at the team level. We found that teams presenting an indirect engagement were more likely to pass the first stage of selection, whereas no significant relationships were found at any of the three evaluation stages for teams presenting a direct engagement. Our findings point to the heterogeneity of the decision-making process within a multistage grant evaluation scheme and suggest that the policy objective of fostering university–industry collaboration does not significantly impact the funding process.


Q Open ◽  
2021 ◽  
Author(s):  
Benjamin Groom ◽  
Francisco Pereira Fontes

Abstract Studies show that cereal diversity positively affects mean yields, suggesting increased crop diversity as a means of increasing production (Di Falco and Chavas 2009, Baumg¨artner and Quaas 2010). In practice though, agricultural development has relied on non- diverse systems. Using the Ethiopian Rural Household Survey panel we revisit this para- dox and disentangle the effects of agro-ecological zones and composition of crop diversity. We find a positive effect of greater cereal diversity on cereal production, but mostly in specific agro-ecological zones and for households who diversify away from a particular low- productivity crop: teff. These results indicate that the scope of cereal diversity to drive increases in output may be limited. Similar to recent studies of biodiversity—ecosystem function relationships (e.g. Jochum et al., 2020), the results suggest that the composition of diverse systems can be more important than the measured diversity itself. In the case of cereal crops in Ethiopia, differences in the yields of particular cereals in the crop mix explain the diversity effect, rather than diversity alone. Since some combinations of crops add to productivity but others do not, productivity related crop choice may not guarantee in situ conservation of crop-diversity on its own. Alternative conservation solutions may well be needed for that.


PLoS ONE ◽  
2021 ◽  
Vol 16 (7) ◽  
pp. e0254170
Author(s):  
Amgad A. Saleh ◽  
Anwar H. Sharafaddin ◽  
Mahmoud H. El_Komy ◽  
Yasser E. Ibrahim ◽  
Younis K. Hamad

Several species of Fusarium cause serious diseases in date palm worldwide. In the present work, 14 SSR markers were used to assess the genetic variation of Fusarium strains isolated from diseased trees in Saudi Arabia. We also studied the effect of different temperatures on mycelial growth of these strains. The pathogenicity of four strains of F. proliferatum was also evaluated on local date palm cultivars. Eleven SSR markers amplified a total of 57 scorable alleles from Fusarium strains. Phylogenetic analysis showed that F. proliferatum strains grouped in one clade with 95% bootstrap value. Within F. proliferatum clade, 14 SSR genotypes were identified, 9 of them were singleton. Four out of the five multi-individual SSR genotypes contained strains isolated from more than one location. Most F. solani strains grouped in one clade with 95% bootstrap value. Overall, the SSR markers previously developed for F. verticillioides and F. oxysporum were very useful in assessing the genetic diversity and confirming the identity of Saudi Fusarium strains. The results from the temperature study showed significant differences in mycelial growth of Fusarium strains at different temperatures tested. The highest average radial growth for Fusarium strains was observed at 25°C, irrespective of species. The four F. proliferatum strains showed significant differences in their pathogenicity on date palm cultivars. It is anticipated that the assessment of genetic diversity, effect of temperature on hyphal growth and pathogenicity of potent pathogenic Fusarium strains recovered from date palm-growing locations in Saudi Arabia can help in effectively controlling these pathogens.


Author(s):  
Iris Glas ◽  
Roel Jennissen ◽  
Godfried Engbersen

AbstractThis study considers and simultaneously tests the role of ethnic diversity and out-group size in relation to individuals’ perceptions of neighborhood cohesion and fear of crime among natives in Dutch neighborhoods. We challenge the way the impact of diversity has been studied previously and propose an alternative measure to examine diversity effects. This results in a better understanding of how and why the ethnic composition of a neighborhood may impact levels of cohesion and fear, and thereby contributes to the literature on the societal effects of ethnic diversity. In addition, attention is paid to the association between cohesion and fear and whether neighborhood cohesion mediates the relationship between ethnic diversity and fear of crime. We apply multilevel equation modeling techniques to analyze the different relationships and use data of the Dutch Safety Monitor (N = 71,760) in combination with detailed register data. Our study is one of the first to detect a diversity effect on cohesion based on the modified diversity measure. We do not find support for the hypothesized diversity effect on fear of crime. Lastly, out-group size turned out to decrease cohesion and increase fear.


2021 ◽  
Vol 6 (1) ◽  
pp. 649
Author(s):  
Eszter Ronai ◽  
Ming Xiang

Previous research has revealed that different scalar expressions give rise to scalar inferences (SIs) at different rates. This variation has been termed scalar diversity. In this study, we investigate the role of Questions Under Discussion (QUDs) in explaining this variation in SI rates. Investigating 43 different scalar expressions, we first show that explicit QUDs robustly affect calculation rates: questions based on the stronger of two scalar terms lead to higher SI rates than questions promoting the weaker one. Second, we explore whether the likelihood of asking the stronger question in general (Question Availability) can explain the scalar diversity effect. Our results suggest that Question Availability is indeed a predictor of scalar diversity, but only for scales where both terms denote intervals (unbounded scales), and not for scales where the stronger member has a fixed meaning (bounded scales).


Author(s):  
Congcong Shen ◽  
Jiang Wang ◽  
Ji-Zheng He ◽  
Feihai Yu ◽  
Yuan Ge

Interactions and feedbacks between aboveground and belowground biomes are fundamental in controlling ecosystem functions and stability. However, the relationship between plant diversity and soil microbial diversity is elusive. Moreover, it remains unknown whether plant diversity loss will deteriorate the stability of soil microbial communities. To shed light on these questions, we conducted a pot-based experiment to manipulate the plant richness gradient (1, 2, 4, 8 species) and plant (Symphyotrichum subulatum (Michx.) G.L.Nesom) invasion status. We found that, in the non-invasion treatment, soil fungal diversity significantly and positively correlated with plant diversity, while the relationship between bacterial and plant diversity was not significant. Under plant invasion, the coupling of plant-fungal alpha diversity relationship was enhanced, but the plant-fungal beta diversity relationship was decoupled. We also found significant positive relationships between plant diversity and soil microbial resistance. The observed positive relationships were determined by turnover (species substitution) and nestedness (species loss) processes for bacterial and fungal communities, respectively. Our study demonstrated that plant diversity enhanced soil fungal diversity and microbial resistance in response to plant invasion. This study expands our knowledge about the aboveground–belowground diversity relationship and diversity-stability relationship. Importance Our study newly showed plant invasion significantly altered relationships between aboveground and belowground diversity. Specifically, plant richness indirectly promoted soil fungal richness through the increase of soil TC without plant invasion, while plant richness had a direct positive effect on soil fungal richness under plant invasion. Our study highlights the plant diversity effect on soil fungal diversity especially under plant invasion, and the plant diversity effect on microbial resistance in response to plant invasion. These novel findings will add important knowledge about the aboveground–belowground diversity relationship and diversity-stability relationship.


2021 ◽  
Author(s):  
Rashmi Shrestha ◽  
Karoliina Huusko ◽  
Anna-Reetta Salonen ◽  
Jussi Heinonsalo

<p>Soil organic matter (SOM) is any material produced by living organisms at various stages of decomposition. SOM enhances soil fertility and quality and influences soil’s ability to fight against soil-borne diseases. Atmospheric CO<sub>2</sub> sequestration into SOM through improved agricultural management practices has been suggested to be a cost effective way to mitigate climate change.</p><p>The build-up of SOM is largely regulated by soil microbial activity. Soil microbes use most plant-derived C and either produce CO<sub>2</sub> or incorporate C into their biomass and after death microbial necromass may contribute to stable SOM. Arbuscular mycorrhizal (AM) fungi are one of the root colonizing soil microbes important in nutrient cycling, plant nutrition, growth and composition and maybe soil aggregation. The benefits of microbes including AM fungi should be thus utilized for climate friendly agriculture by magnifying their benefits via better agricultural management.</p><p>Cover crops use is one of the climate friendly agricultural practices. Cover crops if managed right, can provide several benefits e.g. enhanced soil C sequestration, reduced emissions from fertilizer production, weed suppression, better soil moisture retention and microbial activity. Moreover, use of diverse cover crops may favor higher soil biodiversity leading to high SOM content. In this project, plant diversity impacts on soil and root fungal community composition and microbial activity related to soil C sequestration were studied in a field experiment. In addition, special attention was given to AM fungi.</p><p>The field experiment was started in May, 2019 in Viikki Research farm, University of Helsinki. The experiment consists of seven treatments comparing four different levels of biodiversity to conventional monoculture treatments and bare fallow. Eight different species of cover crops representing four functional traits were sown under barley: 1) nitrogen (N<sub>2</sub>)-fixing + shallow rooting , 2) deep rooting, 3) N<sub>2</sub>-fixing +deep rooting and 4) no N<sub>2</sub>-fixing and shallow rooting. Barley and cover crop root samples and soil samples were collected from two growing seasons 2019 and 2020. Root samples were analyzed for AM fungal colonization %. Soil samples were analyzed for soil microbial biomass and microbial respiration in different seasons. Preliminary results showed no significant cover crop diversity effect on AM fungal colonization % in barley root in 2019. Soil microbial biomass and soil microbial respiration showed seasonal variations but not significant cover crop diversity effect. Therefore, fungal communities in soil and root will be examined using Illumina (MiSeq) sequencing targeting the fungal internal transcribed spacer (ITS) region. Soil enzyme activities and carbon use efficiency will be performed to gain insight into microbial activity. Obtained results will show if microbial community and activity is affected by either plant family composition or plant diversity.</p>


2021 ◽  
Vol 7 (3) ◽  
pp. 173
Author(s):  
Mariem Saadani ◽  
Lydia Hönig ◽  
Steffen Bien ◽  
Michael Koehler ◽  
Gemma Rutten ◽  
...  

Leaf fungal pathogens alter their host species’ performance and, thus, changes in fungal species composition can translate into effects at the tree community scale. Conversely, the functional diversity of tree species in a host tree’s local neighbourhood can affect the host’s foliar fungal infestation. Therefore, understanding the factors that affect fungal infestations is important to advance our understanding of biodiversity-ecosystem functioning (BEF) relationships. Here we make use of the largest BEF tree experiment worldwide, the BEF-China experiment, where we selected tree host species with different neighbour species. Identifying fungal taxa by microscopy and by high-throughput DNA sequencing techniques based on the internal transcribed spacer (ITS) rDNA region, we analysed the fungal richness and infestation rates of our target trees as a function of local species richness. Based on the visual microscopic assessment, we found that a higher tree diversity reduced fungal richness and host-specific fungal infestation in the host’s local neighbourhood, while molecular fungal richness was unaffected. This diversity effect was mainly explained by the decrease in host proportion. Thus, the dilution of host species in the local neighbourhood was the primary mechanism in reducing the fungal disease severity. Overall, our study suggests that diverse forests will suffer less from foliar fungal diseases compared to those with lower diversity.


Oikos ◽  
2020 ◽  
Vol 130 (1) ◽  
pp. 1-14
Author(s):  
Weixian Zeng ◽  
Wenhua Xiang ◽  
Bo Zhou ◽  
Shuai Ouyang ◽  
Yelin Zeng ◽  
...  

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