Digital technology: coming of age?

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Allometry and growth of eight tree taxa in United Kingdom woodlands.

This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0As part of a project to develop predictive ecosystem models of United Kingdom woodlands we have collated data from two United Kingdom woodlands - Wytham Woods and Alice Holt. Here we present data from 582 individual trees of eight taxa in the form of summary variables relating to the allometric relationships between trunk diameter, height, crown height, crown radius and trunk radial growth rate to the tree's light environment and diameter at breast height. In addition the raw data files containing the variables from which the summary data were obtained. Large sample sizes with longitudinal data spanning 22 years make these datasets useful for future studies concerned with the way trees change in size and shape over their life-span

Increasing biomass in Amazonian forest plots

A previous study by Phillips et al. of changes in the biomass of permanent sample plots in Amazonian forests was used to infer the presence of a regional carbon sink. However, these results generated a vigorous debate about sampling and methodological issues. Therefore we present a new analysis of biomass change in old-growth Amazonian forest plots using updated inventory data. We find that across 59 sites, the above-ground dry biomass in trees that are more than 10 cm in diameter (AGB) has increased since plot establishment by 1.22 ± 0.43 Mg per hectare per year (ha-1 yr-1), where 1 ha = 104 m2), or 0.98 ± 0.38 Mg ha-1 yr-1 if individual plot values are weighted by the number of hectare years of monitoring. This significant increase is neither confounded by spatial or temporal variation in wood specific gravity, nor dependent on the allometric equation used to estimate AGB. The conclusion is also robust to uncertainty about diameter measurements for problematic trees: for 34 plots in western Amazon forests a significant increase in AGB is found even with a conservative assumption of zero growth for all trees where diameter measurements were made using optical methods and/or growth rates needed to be estimated following fieldwork. Overall, our results suggest a slightly greater rate of net stand-level change than was reported by Phillips et al. Considering the spatial and temporal scale of sampling and associated studies showing increases in forest growth and stem turnover, the results presented here suggest that the total biomass of these plots has on average increased and that there has been a regional-scale carbon sink in old-growth Amazonian forests during the previous two decades

Management for optimum yield of open pollinated and hybrid canola

Non-Peer ReviewedNewer open pollinated (O.P.) and hybrid canola varieties provide higher yield potential but the management strategies necessary to achieve optimum yield are not well understood. To better understand the levels of inputs required to optimize yield and to enhance producers ability to optimize return on their investment a three year study was conducted at Melfort, Indian Head, and Scott during 1999, 2000 and 2001 with the following objective. Objective: To evaluate the effect of seeding rate, fertilizer addition and fungicides on the optimum yield potential of hybrid and open pollinated canola in the Thick Black, Thin Black and Dark Brown Soil Zones

Fertilizer-N management and nitrous oxide emissions from four sites in Saskatchewan

Non-Peer ReviewedNitrous oxide (N2O) is a powerful greenhouse gas that also depletes stratospheric ozone. The use of fertilizer-N for agricultural purposes is thought to contribute significantly to Canadian anthropogenic N2O emissions. However, the influence of fertilizer-N form, placement, rates of application, and their interaction with soil and climate is not well understood. We report on a 3-year project that compared N2O emissions from four locations with contrasting soil and climatic conditions in Saskatchewan. Spring wheat was fertilized with urea and anhydrous ammonia (AA) banded in the fall, or in mid-row and side-row positions at seeding time in the spring. N2O emissions were similar from AA compared to urea. Emissions tended to be higher when fertilizer-N was placed in a mid-row compared to side-row banded position. Within the range of rates applied in this study, N2O emissions increased linearly with fertilizer-N rate. The percentage of fertilizer-N lost as N2O calculated from our data ranged from near zero (in drought conditions) to 1.0 %. Most values fell at or below 0.4 % with an overall mean of 0.2 %

Surface soil nutrient contents and crop yields after four to seven annual applications of manure

Non-Peer Reviewe

A comparative study of engagement in mobile and wearable health monitoring for bipolar disorder

ObjectivesSelf‐monitoring is recommended for individuals with bipolar disorder, with numerous technological solutions available. This study aimed to identify basic components of these solutions that increase engagement with self‐monitoring.MethodsParticipants with bipolar disorder (n = 47) monitored their symptoms with a Fitbit and a smartphone app and were randomly assigned to either review or not review recorded symptoms weekly. We tested whether individuals would better adhere to and prefer monitoring with passive monitoring with an activity tracker compared to active monitoring with a smartphone app and whether individuals would better adhere to self‐monitoring if their recorded symptoms were reviewed with an interviewer.ResultsMonitoring with a smartphone app achieved similar adherence and preference to Fitbit (P > .85). Linear mixed effects modeling found adherence decreased significantly more over the study for the Fitbit (12% more, P < .001) even though more participants reported they would use the Fitbit over a year compared to the app (72.3% vs 46.8%). Reviewing symptoms weekly did not improve adherence, but most participants reported they would prefer to review symptoms with a clinician (74.5%) and on monthly basis (57.5%) compared to alternatives. Participants endorsed sleep as the most important symptom to monitor, forgetfulness as the largest barrier to self‐monitoring, and raising self‐awareness as the best reason for self‐monitoring.ConclusionsWe recommend a combined strategy of wearable and mobile monitoring that includes reminders, targets raising self‐awareness, and tracks sleep. A clinician may want to review symptoms on a monthly basis.Trial registration: ClinicalTrials.gov NCT03358238.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/154615/1/bdi12849_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/154615/2/bdi12849.pd

Soil and crop response to injected liquid swine manure on two Gray Luvisols

Non-Peer ReviewedIntensive livestock production is increasing in western Canada, and so is the need to dispose of the manure produced. In the last six years or so, the Saskatchewan Centre for Soil Research at the University of Saskatchewan in conjunction with researchers at Prairie Agricultural Machinery Institute (PAMI) and Agriculture and Agri-Food Canada (AAFC) have carried out studies in various areas of manure management. The overall aim of these studies is to determine the viability and sustainability of manure application to agricultural land. The impact of livestock manure application to land is influenced by various factors, among them: soil characteristics, climatic conditions, cropping systems, manure handling and application techniques. Thus, manure management is bound to be site-specific. In order to come up with viable site-specific manure management recommendations, studies have to be conducted in various regions representing the diverse agricultural zones of the province. Although there are various aspects of the impact of manure application to agricultural land, both long-term and short-term, the immediate impact of manure application is typically exhibited in enhanced availability of N in the soil, crop yield and plant N concentration. This is more so with swine manure which has a relatively high concentration of inorganic N. Hence, the objective of this study was to determine the effects of rate and frequency of swine manure application on crop performance and soil available N in the Gray and Dark Gray soil zones of Saskatchewan

Increased papillae growth and enhanced short-chain fatty acid absorption in the rumen of goats are associated with transient increases in cyclin D1 expression after ruminal butyrate infusion

We tested the hypothesis that the proliferative effects of intraruminal butyrate infusions on the ruminal epithelium are linked to upregulation in cyclin D1 (CCND1), the cyclin-dependent kinase 4 (CDK4), and their possible association with enhanced absorption of short-chain fatty acids (SCFA). Goats (n=23) in 2 experiments (Exp.) were fed 200 g/d concentrate and hay ad libitum. In Exp. 1, goats received an intraruminal infusion of sodium butyrate at 0.3 (group B, n=8) or 0 (group C, n=7) g/kg of body weight (BW) per day before morning feeding for 28 d and were slaughtered 8 h after the butyrate infusion. In Exp. 2, goats (n=8) received butyrate infusion and feeding as in Exp. 1. On d 28, epithelial samples were biopsied from the antrium ruminis at 0, 3, and 7 h after the last butyrate infusion. In Exp. 1, the ruminal molar proportional concentration of butyrate increased in group B by about 110% after butyrate infusion and remained elevated for 1.5 h; thereafter, it gradually returned to the baseline (preinfusion) level. In group C, the molar proportional concentration of butyrate was unchanged over the time points. The length and width of papillae increased in B compared with C; this was associated with increased numbers of cells and cell layers in the epithelial strata and an increase in the surface area of 82%. The mRNA expression of CCND1 increased transiently at 3 h but returned to the preinfusion level at 7 h following butyrate infusion in Exp. 2. However, it did not differ between B and C in Exp. 1, in which the ruminal epithelium was sampled at 8 h after butyrate infusion. The mRNA expression of the monocarboxylate transporter MCT4, but not MCT1, was stably upregulated in B compared with C. The estimated absorption rate of total SCFA (%/h) increased in B compared with C. We conclude that transient increases in cyclin D1 transcription contribute to butyrate-induced papillae growth and subsequently to the increased absorption of SCFA in the ruminal epithelium of goats

Comparsion of agronomic performance of N fertilizer placement and formulation on wheat, canola, and flax at four sites in Saskatchewan

Non-Peer Reviewe