Can We Predict How Earthworm Effects on Plant Growth Vary with Soil Properties?

Earthworms are usually assumed to enhance plant growth through different mechanisms which are now clearly identified. It is however difficult to determine their relative importance, and to predict a priori the strength and direction of the effects of a given earthworm species on a given plant. Soil properties are likely to be very influential in determining plant responses to earthworm activities. They are likely to change the relative strength of the various mechanisms involved in plant-earthworm interactions. In this paper, we review the different rationales used to explain changes in earthworm effect due to soil type. Then, we systematically discuss the effect of main soil characteristics (soil texture, OM, and nutrient contents) on the different mechanisms allowing earthworm to influence plant growth. Finally, we identify the main shortcomings in our knowledge and point out the new experimental and meta-analytical approaches that need to be developed. An example of such a meta-analysis is given and means to go further are suggested. The result highlights a strong positive effect size in sandy soil and a weakly negative effect in clayey soil.

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The effects of replaced topsoil of different depths on the vegetation and soil properties of reclaimed coal mine spoils in an alpine mining area

Israel Journal of Ecology and Evolution ◽

10.1163/22244662-20191048 ◽

2019 ◽

Vol 65 (3-4) ◽

pp. 92-105

Author(s):

Xinguang Yang ◽

Xilai Li ◽

Mingming Shi ◽

Liqun Jin ◽

Huafang Sun

Keyword(s):

Plant Growth ◽

Soil Properties ◽

Coal Mine ◽

Growth Parameters ◽

Soil Depth ◽

Mining Area ◽

Vegetation Coverage ◽

Mine Spoils ◽

Plant Soil ◽

Different Depths

Replacement of topsoil to an appropriate depth is one of the key methods for ecological restoration. The objective of this study was to investigate the effects of topsoil replacement depth on vegetation and soil properties, and to identify the optimum soil depth for reclamation of coal mine spoils in a cold alpine mining area. We sowed 3 herbaceous species after coal mine spoil heaps were treated with topsoil to 3 depths (0, 20‒25, 40‒45 cm). The variations in vegetation community structure, plant growth, soil properties were measured at different replaced topsoil depths. The correlations between plant and soil properties were analyzed statistically. The results showed species richness, diversity and evenness were not significantly different among different depths of topsoil (P > 0.05). Vegetation coverage, density, height and aboveground biomass increased significantly (P < 0.05) with increasing topsoil depth. Soil properties did not change significantly with increasing topsoil depth (P > 0.05), but soil organic matter was significantly higher at 40‒45 cm topsoil depth than at other two depths (P < 0.05). All soil properties, with the exception of total potassium, were positively correlated with the plant growth parameters. The 40‒45 cm topsoil depth of replacement should be considered as effective method in reclaiming coal mine spoils. The use of both topsoil replacement to a depth of 40‒45 cm and sowing of suitable herbaceous seeds is found to be an effective restoration strategy. Additionally, fertilization might be used as a substitute for artificial topsoil replacement to improve soil quality and speed up revegetation process by the positive plant-soil interactions.

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Pervasive and strong effects of plants on soil chemistry: a meta-analysis of individual plant ‘Zinke’ effects

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2015.1001 ◽

2015 ◽

Vol 282 (1812) ◽

pp. 20151001 ◽

Cited By ~ 53

Author(s):

Bonnie G. Waring ◽

Leonor Álvarez-Cansino ◽

Kathryn E. Barry ◽

Kristen K. Becklund ◽

Sarah Dale ◽

...

Keyword(s):

Soil Properties ◽

Meta Analysis ◽

Soil Heterogeneity ◽

Individual Plant ◽

Ecological Processes ◽

Plant Soil ◽

Local Soil ◽

Plant Effects ◽

Intensively Managed ◽

Managed Ecosystems

Plant species leave a chemical signature in the soils below them, generating fine-scale spatial variation that drives ecological processes. Since the publication of a seminal paper on plant-mediated soil heterogeneity by Paul Zinke in 1962, a robust literature has developed examining effects of individual plants on their local environments (individual plant effects). Here, we synthesize this work using meta-analysis to show that plant effects are strong and pervasive across ecosystems on six continents. Overall, soil properties beneath individual plants differ from those of neighbours by an average of 41%. Although the magnitudes of individual plant effects exhibit weak relationships with climate and latitude, they are significantly stronger in deserts and tundra than forests, and weaker in intensively managed ecosystems. The ubiquitous effects of plant individuals and species on local soil properties imply that individual plant effects have a role in plant–soil feedbacks, linking individual plants with biogeochemical processes at the ecosystem scale.

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Soil phosphorus, biology and time: A case for publishing inconclusive data, and the undeniable relevance of tennis balls

10.5194/egusphere-egu21-16487 ◽

2021 ◽

Author(s):

Phil Haygarth ◽

Malika Mezeli ◽

Timothy George ◽

Roy Neilson ◽

Martin Blackwell

Keyword(s):

Plant Growth ◽

Trophic Interactions ◽

Meta Analysis ◽

Soil Phosphorus ◽

Plant Responses ◽

Soil P ◽

The Impact ◽

Time Point

The association of microorganisms and soil nutrient cycles has been observed for over 200 years, and their importance in the soil phosphorus (P) cycle is well documented. In-soil trophic interactions between bacteria and bacterivorous nematodes have been implicated in increased plant access to soil organic P (Po).However, the existing data remains inconclusive and lacks detail and predictability.&#160; This work aimed to (1) assess the impact of nematodes as an additional trophic-level on Po use by plants in arable systems and (2) further understand the mechanisms of in-soil trophic interactions in improving plant acquisition of Po. To address these aims criteria based meta-analysis, glasshouse plant growth trials, in vitro and soil, and long term experimental (LTE) platforms were used.&#160; Results led to the conclusion that nematodes did not improve plant acquisition of Po per se. Time, soil P concentration and soil biological community composition had significant impacts on plant response. Although these factors were identified in two contrasting studies, their impacts on plant responses were stochastic. Complexity, which describes the average number of trophic links per species, framed an understanding of these data where they evaded predictability, specifically when considering the temporal nature of these relationships. For example, data from the meta-analysis and the plant growth trials demonstrated it was not simply the additive effect of the number of species or the addition of a specific species which resulted in predictable plant P responses.&#160; Nematode community analysis from the LTE&#8217;s yielded characteristics indicative of stability in the biotic component of systems previously considered disturbed (arable). This exposed the question of the nature of disturbance (whether natural or anthropogenic). Additionally, it highlighted the importance of which successional time-point was being studied and the impact this has on the data captured.&#160; Data collected from this long-term experiment, plant growth trials and the meta-analysis highlights the importance of the temporal resolution, and the time-point at which we are observing these dynamic systems. It is argued that in-conclusive or negative results could represent true details of these systems, where they represent points of transition between stable and/or predictable states and a usual characteristic of the complex system.&#160; Therefore, inconclusive data should not be omitted from the research library, exclusion of such data could lead to incomplete observations and incorrect assumptions. Better practices should be designed and implemented to ensure publication bias is not a barrier to our understanding of these systems.

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Trajectory research in children on the autism spectrum: a scoping review protocol

BMJ Open ◽

10.1136/bmjopen-2021-053443 ◽

2021 ◽

Vol 11 (11) ◽

pp. e053443

Author(s):

Stephen Gentles ◽

Eric Duku ◽

Connor Kerns ◽

Alana J McVey ◽

Michelle C Hunsche ◽

...

Keyword(s):

Scoping Review ◽

Data Extraction ◽

Meta Analysis ◽

A Priori ◽

Autism Spectrum ◽

Medical Librarian ◽

Review Protocol ◽

Analytical Approaches ◽

Trajectory Methods ◽

Full Text Screening

IntroductionLongitudinal trajectory methods, featuring outcome assessments at three or more time points, are increasingly being used as appropriate approaches to understand developmental pathways of people on the autism spectrum across the lifespan. Understanding the scope of this rapidly expanding body of research can help inform future trajectory studies and identify areas for potential meta-analysis as well as key evidence gaps. We present the protocol for a scoping review whose objective is to identify and summarise the scope of research that uses a longitudinal trajectory study design to examine development in children diagnosed with autism. Specifically, we will identify outcome domains and age intervals that have been well characterised, areas where further research is needed and the historical use of various longitudinal trajectory analytical approaches.Methods and analysisWe outline the methods for the proposed scoping review according to the framework outlined by Arksey and O’Malley, with subsequent clarifications and enhancements by other authors. Using a search strategy developed by a medical librarian, we will search six databases for relevant publications. Titles and abstracts will be screened in duplicate, followed by full-text screening. Data extraction fields developed predominantly a priori from a set of guiding subquestions will be used to chart relevant data. The findings will include quantitative aggregate summaries, narrative summaries, and appraisal of trajectory studies according to our methodological subquestions. We will consult autistic self-advocate and parent–caregiver stakeholders to facilitate interpretation of the findings.Ethics and disseminationResearch ethics approval is not required for this scoping review. The results will be presented to researcher, care professional, policy-maker and stakeholder audiences at local and international conferences, other dissemination activities and published in a peer-reviewed journal.

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Plant Responses to Changing Water Supply and Availability in High Elevation Ecosystems: A Quantitative Systematic Review and Meta-Analysis

Land ◽

10.3390/land10111150 ◽

2021 ◽

Vol 10 (11) ◽

pp. 1150

Author(s):

Emma Sumner ◽

Susanna Venn

Keyword(s):

Systematic Review ◽

Plant Growth ◽

Water Supply ◽

Confidence Intervals ◽

Meta Analysis ◽

Growing Season ◽

High Elevation ◽

Plant Responses ◽

Quantitative Systematic Review ◽

Growing Season Precipitation

Climate change is expected to lead to changes to the amount, frequency, intensity, and timing of precipitation and subsequent water supply and its availability to plants in mountain regions worldwide. This is likely to affect plant growth and physiological performance, with subsequent effects to the functioning of many important high-elevation ecosystems. We conducted a quantitative systematic review and meta-analysis of the effects of altered water supply on plants from high elevation ecosystems. We found a clear negative response of plants to decreases in water supply (mean Hedges’ g = −0.75, 95% confidence intervals: −1.09 to −0.41), and a neutral response to increases in water supply (mean Hedges’ g = 0.10, 95% confidence intervals: 0.43 to 0.62). Responses to decreases in water supply appear to be related to the magnitude of change in water supply, plant growth form, and to the measured response attribute. Changes to precipitation and water supply are likely to have important consequences for plant growth in high elevation ecosystems, with vegetation change more likely be triggered by reductions than increases in growing season precipitation. High elevation ecosystems that experience future reductions in growing-season precipitation are likely to exhibit plant responses such as reduced growth and higher allocation of carbohydrates to roots.

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Local plant adaptation across a subarctic elevational gradient

Royal Society Open Science ◽

10.1098/rsos.140141 ◽

2014 ◽

Vol 1 (3) ◽

pp. 140141 ◽

Cited By ~ 7

Author(s):

Paul Kardol ◽

Jonathan R. De Long ◽

David A. Wardle

Keyword(s):

Plant Growth ◽

Soil Properties ◽

Elevational Gradient ◽

Interactive Effects ◽

Plant Responses ◽

Plant Adaptation ◽

Affected Plant ◽

Local Plant ◽

Soil Origin ◽

Increasing Temperature

Predicting how plants will respond to global warming necessitates understanding of local plant adaptation to temperature. Temperature may exert selective effects on plants directly, and also indirectly through environmental factors that covary with temperature, notably soil properties. However, studies on the interactive effects of temperature and soil properties on plant adaptation are rare, and the role of abiotic versus biotic soil properties in plant adaptation to temperature remains untested. We performed two growth chamber experiments using soils and Bistorta vivipara bulbil ecotypes from a subarctic elevational gradient (temperature range: ±3 ° C) in northern Sweden to disentangle effects of local ecotype, temperature, and biotic and abiotic properties of soil origin on plant growth. We found partial evidence for local adaption to temperature. Although soil origin affected plant growth, we did not find support for local adaptation to either abiotic or biotic soil properties, and there were no interactive effects of soil origin with ecotype or temperature. Our results indicate that ecotypic variation can be an important driver of plant responses to the direct effects of increasing temperature, while responses to covariation in soil properties are of a phenotypic, rather than adaptive, nature.

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Replication of the Superstition and Performance Study by

Social Psychology ◽

10.1027/1864-9335/a000190 ◽

2014 ◽

Vol 45 (3) ◽

pp. 239-245 ◽

Cited By ~ 18

Author(s):

Robert J. Calin-Jageman ◽

Tracy L. Caldwell

Keyword(s):

Task Difficulty ◽

Statistical Power ◽

Meta Analysis ◽

A Priori ◽

Significant Heterogeneity ◽

Performance Study ◽

Improve Performance ◽

Research Designs ◽

Series Of Experiments ◽

And Performance

A recent series of experiments suggests that fostering superstitions can substantially improve performance on a variety of motor and cognitive tasks ( Damisch, Stoberock, & Mussweiler, 2010 ). We conducted two high-powered and precise replications of one of these experiments, examining if telling participants they had a lucky golf ball could improve their performance on a 10-shot golf task relative to controls. We found that the effect of superstition on performance is elusive: Participants told they had a lucky ball performed almost identically to controls. Our failure to replicate the target study was not due to lack of impact, lack of statistical power, differences in task difficulty, nor differences in participant belief in luck. A meta-analysis indicates significant heterogeneity in the effect of superstition on performance. This could be due to an unknown moderator, but no effect was observed among the studies with the strongest research designs (e.g., high power, a priori sampling plan).

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Plastic Mulch Color Effects on Light Micro-environment and Watermelon Plant Growth

HortScience ◽

10.21273/hortsci.33.3.474d ◽

1998 ◽

Vol 33 (3) ◽

pp. 474d-474

Author(s):

N.K. Damayanthi Ranwala ◽

Dennis R. Decoteau

Keyword(s):

Plant Growth ◽

Light Transmission ◽

Root Zone ◽

Dry Mass ◽

Plant Responses ◽

Plastic Mulch ◽

Plant Parts ◽

Reflected Light ◽

Total Light ◽

Dry Mass Partitioning

This study was conducted to evaluate the spectral properties of various colored plastic color mulches and to determine the effects of upwardly reflected light from the mulch surfaces on watermelon plant growth when differences in root zone temperatures are minimized. Two-week-old watermelon plants were grown with black mulch, red-painted mulch, SRM-Red mulch (Sonoco, Inc., Harstville, S.C.), and white mulch. Total light reflection (58 μmol·m–2·s–1 in 400–700 nm) and red: far-red (R:FR = 0.44) of reflected light were lower in black mulch and highest in white mulch (634 and 0.92, respectively). Both black mulch and white mulch had same blue:red (B:R = 0.6) while white mulch had higher B:FR (0.58) in reflected light compared to black mulch (0.26). Reflective properties of red mulches were somewhat similar, and R:FR, B:R, and B:FR were 0.8, 0.2, and 0.18, respectively. However, SRM-Red mulch had highest total light (355 μmol·m–2·s–1 in 400–700 nm) transmission through the mulch, and R:FR, B:R, and B:FR were 0.84, 0.28, and 0.23, respectively. Light transmission through the other mulches was nonsignificant. Watermelon plants grown with black mulch and red mulches had higher internode lengths compared to white mulch after 20 days. Further, plants grown under black had significant higher petiole elongation accompanied with higher dry mass partitioning to petioles, and lower partitioning to roots, stems, and leaves. There was no effects of surface mulch color on total plant dry mass or photosynthesis although plants with black had higher transpiration rate. This suggests the differential regulation of dry mass partitioning among plant parts due to mulch color. The similar plant responses with black mulch and white mulch to plants treated with FR or R light at the end of photoperiod implies the involvement of phytochrome regulation of growth due to mulch surface color.

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Web-based Tools for Drug Repurposing: Successful Examples of Collaborative Research

Current Medicinal Chemistry ◽

10.2174/0929867327666200128111925 ◽

2020 ◽

Vol 28 (1) ◽

pp. 181-195

Author(s):

Quentin Vanhaelen

Keyword(s):

User Interfaces ◽

Collaborative Research ◽

Meta Analysis ◽

A Priori ◽

Drug Repurposing ◽

Data Access ◽

Estimation Methods ◽

Large Set ◽

Computational Tools ◽

Web Based

: Computational approaches have been proven to be complementary tools of interest in identifying potential candidates for drug repurposing. However, although the methods developed so far offer interesting opportunities and could contribute to solving issues faced by the pharmaceutical sector, they also come with their constraints. Indeed, specific challenges ranging from data access, standardization and integration to the implementation of reliable and coherent validation methods must be addressed to allow systematic use at a larger scale. In this mini-review, we cover computational tools recently developed for addressing some of these challenges. This includes specific databases providing accessibility to a large set of curated data with standardized annotations, web-based tools integrating flexible user interfaces to perform fast computational repurposing experiments and standardized datasets specifically annotated and balanced for validating new computational drug repurposing methods. Interestingly, these new databases combined with the increasing number of information about the outcomes of drug repurposing studies can be used to perform a meta-analysis to identify key properties associated with successful drug repurposing cases. This information could further be used to design estimation methods to compute a priori assessment of the repurposing possibilities.

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P34 Characteristics, diagnosis and management of Cushing’s disease - A systematic review and meta-analysis

BJS Open ◽

10.1093/bjsopen/zrab032.033 ◽

2021 ◽

Vol 5 (Supplement_1) ◽

Author(s):

Chan Hee Koh ◽

Danyal Z Khan ◽

Ronneil Digpal ◽

Hugo Layard Horsfall ◽

Hani J Marcus ◽

...

Keyword(s):

Clinical Practice ◽

Cushing’S Disease ◽

Meta Analysis ◽

A Priori ◽

Pituitary Surgery ◽

Serum Cortisol ◽

Cushing's Disease ◽

Diagnosis And Management ◽

Over Time

Abstract Introduction The clinical practice and research in the diagnosis and management of Cushing’s disease remains heterogeneous and challenging to this day. We sought to establish the characteristics of Cushing’s disease, and the trends in diagnosis, management and reporting in this field. Methods Searches of PubMed and Embase were conducted. Study protocol was registered a-priori. Random-effects analyses were conducted to establish numerical estimates. Results Our screening returned 159 papers. The average age of adult patients with Cushing’s disease was 39.3, and 13.6 for children. The male:female ratio was 1:3. 8% of patients had undergone previous transsphenoidal resection. The ratio of macroadenomas: microadenomas:imaging-undetectable adenomas was 18:53:29. The most commonly reported preoperative biochemical investigations were serum cortisol (average 26.4µg/dL) and ACTH (77.5pg/dL). Postoperative cortisol was most frequently used to define remission (74.8%), most commonly with threshold of 5µg/dL (44.8%). Average remission rates were 77.8% with recurrence rate of 13.9%. Median follow-up was 38 months. Majority of papers reported age (81.9%) and sex (79.4%). Only 56.6% reported whether their patients had previous pituitary surgery. 45.3% reported whether their adenomas were macroadenoma, microadenoma or undetectable. Only 24.1% reported preoperative cortisol, and this did not improve over time. 60.4% reported numerical thresholds for cortisol in defining remission, and this improved significantly over time (p = 0.004). Visual inspection of bubbleplots showed increasing preference for threshold of 5µg/dL. 70.4% reported the length of follow up. Conclusion We quantified the characteristics of Cushing’s disease, and analysed the trends in investigation and reporting. This review may help to inform future efforts in forming guidelines for research and clinical practice.

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