Plant, soil and faunal responses to a contrived pH gradient

© 2021, The Author(s). Purpose: To build a more holistic understanding of soil pH change we assessed the synchronised effects of a contrived soil pH change on soil chemistry, vegetation growth and nutrition, and soil faunal abundance and diversity. Methods: We established a fifteen year old field experiment with a contrived pH gradient (pH 4.3 to 6.3) and measured the effect on soil chemistry, plant biomass and elemental composition and the impact of these changes on soil fauna (earthworms, nematodes, rotifers and tardigrades) and biological indices (based on ecological group structures of earthworms and nematodes). A single 20 × 20 × 20 cm soil block was excavated from each sample site to directly attribute biotic parameters in the block to the abiotic (soil) conditions. Results: Acidification affected the extractable concentrations of Al, Ca, Mn and P and the C:N ratio of the soil and caused a reduction in plant Ca (rs for pH vs Ca = 0.804 p < 0.01), an increase in plant Mn (rs = −0.450 p = 0.019), along with significant decrease in root:shoot ratio (rs = 0.638, p < 0.01). There was a significant positive correlation between pH and earthworm index (rs = 0.606, p < 0.01), and a negative correlation between pH and nematode index (rs = −0.515, p < 0.01). Conclusion: Soil pH influenced the mobility of Ca, Al, Mn and P, which in turn has impacted on plant tissue chemistry and plant biomass ratios. Linked changes in soil chemistry and vegetation had a corresponding effect on the abundance and diversity of nematodes and earthworms in the soil blocks

LEGO® bricks as building blocks for centimeter-scale biological environments

LEGO bricks are commercially available interlocking pieces of plastic that are conventionally used as toys. We describe their use to build engineered environments for cm-scale biological systems, in particular plant roots. Specifically, we take advantage of the unique modularity of these building blocks to create inexpensive, transparent, reconfigurable, and highly scalable environments for plant growth in which structural obstacles and chemical gradients can be precisely engineered to mimic soil

Plant growth environments with programmable relative humidity and homogeneous nutrient availability

We describe the design, characterization, and use of “programmable”, sterile growth environments for individual (or small sets of) plants. The specific relative humidities and nutrient availability experienced by the plant is established (RH between 15% and 95%; nutrient concentration as desired) during the setup of the growth environment, which takes about 5 minutes and <1$ in disposable cost. These systems maintain these environmental parameters constant for at least 14 days with minimal intervention (one minute every two days). The design is composed entirely of off-the-shelf components (e.g., LEGO® bricks) and is characterized by (i) a separation of root and shoot environment (which is physiologically relevant and facilitates imposing specific conditions on the root system, e.g., darkness), (ii) the development of the root system on a flat surface, where the root enjoys constant contact with nutrient solution and air, (iii) a compatibility with root phenotyping. We demonstrate phenotyping by characterizing root systems of Brassica rapa plants growing in different relative humidities (55%, 75%, and 95%). While most phenotypes were found to be sensitive to these environmental changes, a phenotype tightly associated with root system topology – the size distribution of the areas encircled by roots – appeared to be remarkably and counterintuitively insensitive to humidity changes. These setups combine many of the advantages of hydroponics conditions (e.g., root phenotyping, complete control over nutrient composition, scalability) and soil conditions (e.g., aeration of roots, shading of roots), while being comparable in cost and setup time to Magenta® boxes

Long-term acidification of pH neutral grasslands affects soil biodiversity, fertility and function in a heathland restoration

In the wider context of heathland restoration, we investigated how field scale experimental acidification with sulphur (sulfur)affected soil biodiversity, fertility and function over a period of 17 years. A field experiment was conducted in the Isle of Purbeck, England, using ferrous sulphate and elemental sulphur as acidifying agents. We tested the effects of acidification on soil fertility, plant communities, litter decomposition, microbiology (including fungi bacteria and actinomycetes), arbuscular and ericoid mycorrhizal colonisation, and soil fauna (including earthworms, nematodes, rotifers and tardigrades). We found that elemental sulphur had a considerable and persistent effect on soil pH, lowering it to levels found in the surrounding reference acid grassland and heathland sites. A newly adapted heathland restoration index based on soil chemistry, found that elemental sulphur was by far the most successful treatment leading to soil conditions similar to the heathlands. Overall, acidification caused a loss of base cations and an increase in toxic aluminium compounds. Consequently the more mesotrophic components of soil biology were reduced by acidification during the course of the experiment. This transformed the soil biological system into one typical of acid grasslands and heathlands. Concomitant litter decomposition was similarly inhibited by acidification, with the microbiota more strongly hindered in acidified soil than the macroscopic fauna. Acidification resulted in a reduction in nematode and rotifer abundance and earthworm biomass. The vegetation community was also strongly modified by the elemental sulphur treatments and, where grazing was restricted, soil acidification allowed a restored heathland community to endure. Arbuscular mycorrhizal colonisation of grasses was reduced where heather plants were established, while ericoid mycorrhizas had developed sufficient populations in the acidified pastures to match the colonisation rate in the native heathlands

Evaluation of Three Primary Teachers’ Approaches to Teaching Scientific Concepts in Persuasive Ways

The research set out in this paper seeks to develop pedagogical knowledge regarding how persuasive teaching approaches can be developed in primary science classrooms. To achieve this, the paper examines three case studies in which the teachers have been charged to develop and implement teaching strategies designed to persuade their children of the usefulness and validity of target scientific concepts. The analysis probes the teachers’ choice of contexts and patterns of discourse using criteria drawn from the sociocultural literature. Outcomes of the study exemplify how the teachers’ choices of learning contexts fail to emphasise the functionality of the target concepts and as a consequence scant rewards are provided for the children to participate actively in conceptually rich discourse. The final part of the paper explores how the development of what the author calls theme-specific plots, could be used to help teachers to stage teaching and learning performances which emphasise the functionality of specific explanatory models

Improvement of soil structure and crop yield by adding organic matter to soil (AHDB Project Report No.576)

Soil quality is intimately linked with soil biology. Recent research at Rothamsted Research (RRes) has shown that addition of Farm Yard Manure (FYM) can improve barley grain and straw yield within two years by more than 1t ha−1 each. Penetrometer measurements attribute this increase to an improvement in ease of root exploration in the soil, which, in turn, may be attributed to an increase in earthworm biomass and activity. These results suggest benefits from adding the right kind of organic matter can be achieved relatively rapidly in soils by feeding the soil organisms, which then bring about desirable changes in soil condition. We hypothesised crop yields will increase quickly (within four years) as a result of improved soil physical condition that results from feeding soil organisms, especially earthworms, with relatively small amounts of suitable organic matter additions. To test these ideas, we set up field experiments at Rothamsted Research farm (flinty clay loam soil) in Harpenden between 2012 to 2017. The four harvest years of the project allowed three field experiments to run. These covered two tillage regimes, four arable crop rotation combinations, five nitrogen treatments and fourteen organic matter recipes at a range of concentrations. Additionally, two outdoor pot experiments, growing winter wheat under a range of earthworm amendments, seven organic matter recipes and four soil types, were studied. The influence on soil physical properties, crop yields and earthworm populations were examined on selected plots and pots. Different methods were used on selected plots to examine soil physical properties. Methods included bulk density, infiltration, penetrometer, aggregate stability, resistance to ploughing or CT scans of the pores in soil. Earthworm populations were determined on selected plots by handsorting one 20 x 20 x 20cm cube taken from a plot. Microbial biomass, fungal biomass and microbial community composition were also measured. Five commercial growers’ trials were held at Haines Barn, Woodbridge, Butterwick, Terrington and Spalding (England). Data from three independent trials at AFBI (Northern Ireland), three at NIAB (England) and one at JHI (Scotland) were also included. These data included some yield data on cereal or horticulture cultivations, soil physical measurements and an earthworm survey. Crop yields were determined on every plot, with a beneficial yield effect detected on both the Rothamsted trials after two years of amendments. Amended soils in a pot experiment testing the effect of soil type had more tillers and greater grain masses than unamended soils but there was no significant difference between soil types. Yield improvement in a European study did increase with texture in the order clay<silty clay loam<sand. Differences in soil physical properties were not evident after two years. This was linked to the high proportion of flint in these soils (20 % stones by volume) affecting some of the methods. Adding organic amendments to soil in two field experiments was found to change the yield response of four crops (spring barley, winter wheat, oilseed rape, winter oats) to N. Amendments increased yields but by a greater amount in a tilled system than a system with reduced tillage. An increasing amount of amendment increased yield but there is evidence of a maximum in this response to amendment, beyond which the yield response declines. The amendments contained nutrients which helps to explain why crops yield well at low rates of mineral N application but not why they yield more overall. The full benefits from amending soil does not appear immediately and two or three years of application may be needed. Spring crops appear to benefit more than winter crops but in years when yields are good the benefits of amending soil are less clear, both in absolute and relative terms. Quality was either unaffected by amendment (N) or improved (TGW) and to the extent that might attract a premium (oil). A straightforward economic analysis suggests that acquiring and spreading amendments should cost no more than £50 t−1 C spread if amending is to be economic. Several additional pieces of work were undertaken to try to understand why yields respond to organic amendments. Our initial hypothesis was that organisms rearrange the structure of soil to their own benefit while dwelling there and that this in turn improved the environment for crops. Amendments increased microbial biomass, earthworm biomass (g m−2) and numbers (m−2) on certain occasions but there was no overall statistical difference between amendments and no statistically consistent benefit to mass or numbers of organisms. Means to increase earthworm numbers, such as grinding up part of the amendment to make it more easily ingested by earthworms, staging the application four times per year or eliminating fungicide from the earthworm’s diet, all increased earthworm numbers and biomass but did not increase yields in the field. All wheat crops grown with non-crop residue amendments were first wheats in these experiments. However, FYM was found to have altered N response curve of wheat in historic experiments where take-all was additionally present, such that up to 1t extra grain ha−1 was obtained. Infiltration of water through soil was increased by amending soil, but not significantly. The plough draught forces (in kPa) were significantly reduced by amending soil and in proportion to the amount and energy content of the amendments. No significant difference, however, was found in measurements of soil mechanical impedance to a hand-operated penetrometer, nor in bulk density. However, there was no significant relationship between draught forces in autumn with the yield the following summer except, between autumn 2014 and summer 2015. Despite the lack of conclusive evidence, it is surmised that amendments increase yield and that the most plausible mechanism is that the soil organisms have improved the structure or the ease with which the plant can rearrange the soil structure to its own benefit

A simple and versatile 2-dimensional platform to study plant germination and growth under controlled humidity

We describe a simple, inexpensive, but remarkably versatile and controlled growth environment for the observation of plant germination and seedling root growth on a flat, horizontal surface over periods of weeks. The setup provides to each plant a controlled humidity (between 56% and 91% RH), and contact with both nutrients and atmosphere. The flat and horizontal geometry of the surface supporting the roots eliminates the gravitropic bias on their development and facilitates the imaging of the entire root system. Experiments can be setup under sterile conditions and then transferred to a non-sterile environment. The system can be assembled in 1-2 minutes, costs approximately 8.78$per plant, is almost entirely reusable (0.43$ per experiment in disposables), and is easily scalable to a variety of plants. We demonstrate the performance of the system by germinating, growing, and imaging Wheat (Triticum aestivum), Corn (Zea mays), and Wisconsin Fast Plants (Brassica rapa). Germination rates were close to those expected for optimal conditions

Instruments to measure patient experience of healthcare quality in hospitals: a systematic review

Improving and sustaining the quality of hospital care is an international challenge. Patient experience data can be used to target improvement and research. However, the use of patient experience data has been hindered by confusion over multiple instruments (questionnaires) with unknown psychometric testing and utility.MethodsWe conducted a systematic review and utility critique of questionnaires to measure patient experience of healthcare quality in hospitals. Databases (Medical Literature Analysis and Retrieval System (MEDLINE), Cumulative Index to Nursing and Allied Health Literature (CINAHL), Psychological Information (PsychINFO) and Web of Knowledge until end of November 2013) and grey literature were scrutinised. Inclusion criteria were applied to all records with a 10 % sample independently checked. Critique included (1) application of COSMIN checklists to assess the quality of each psychometric study, (2) critique of psychometric results of each study using Terwee et al. criteria and (3) development and critique of additional aspects of utility for each instrument. Two independent reviewers completed each critique. Synthesis included combining findings in a utility matrix.We obtained 1157 records. Of these, 26 papers measuring patient experience of hospital quality of care were identified examining 11 international instruments. We found evidence of extensive theoretical/development work. The quality of methods and results was variable but mostly of a high standard. Additional aspects of utility found that (1) cost efficiency was mostly poor, due to the resource necessary to obtain reliable samples; (2) acceptability of most instruments was good and (3) educational impact was variable, with evidence on the ease of use, for approximately half of the questionnaires.ConclusionsSelecting the right patient experience instrument depends on a balanced consideration of aspects of utility, aided by the matrix. Data required for high stakes purposes requires a high degree of reliability and validity, while those used for quality improvement may tolerate lower levels of reliability in favour of other aspects of utility (educational impact, cost and acceptability)

The National Adult Inpatient Survey conducted in the English National Health Service from 2002 to 2009: how have the data been used and what do we know as a result?

<p>Abstract</p> <p>Background</p> <p>When it was initiated in 2001, England's national patient survey programme was one of the first in the world and has now been widely emulated in other healthcare systems. The aim of the survey programme was to make the National Health Service (NHS) more "patient centred" and more responsive to patient feedback. The national inpatient survey has now been running in England annually since 2002 gathering data from over 600,000 patients. The aim of this study is to investigate how the data have been used and to summarise what has been learned about patients' evaluation of care as a result.</p> <p>Methods</p> <p>Two independent researchers systematically gathered all research that included analyses of the English national adult inpatient survey data. Journals, databases and relevant websites were searched. Publications prior to 2002 were excluded. Articles were also identified following consultation with experts. All documents were then critically appraised by two co-authors both of whom have a background in statistical analysis.</p> <p>Results</p> <p>We found that the majority of the studies identified were reports produced by organisations contracted to gather the data or co-ordinate the data collection and used mainly descriptive statistics. A few articles used the survey data for evidence based reporting or linked the survey to other healthcare data. The patient's socio-demographic characteristics appeared to influence their evaluation of their care but characteristics of the workforce and the. At a national level, the results of the survey have been remarkably stable over time. Only in those areas where there have been co-ordinated government-led campaigns, targets and incentives, have improvements been shown. The main findings of the review are that while the survey data have been used for different purposes they seem to have incited little academic interest.</p> <p>Conclusions</p> <p>The national inpatient survey has been a useful resource for many authors and organisations but the full potential inherent in this large, longitudinal publicly available dataset about patients' experiences has not as yet been fully exploited.</p> <p>This review suggests that the presence of survey results alone is not enough to improve patients' experiences and further research is required to understand whether and how the survey can be best used to improve standards of care in the NHS.</p