scholarly journals Effects of Repeated Application of Organic Soil Amendments on Horticultural Soil Physicochemical Properties, Nitrogen Budget and Yield

Horticulturae ◽  
2021 ◽  
Vol 7 (10) ◽  
pp. 371
Author(s):  
Sarah Duddigan ◽  
Paul D. Alexander ◽  
Liz J. Shaw ◽  
Chris D. Collins

Application of organic amendments to soil is commonplace in domestic gardening. However, a vast array of materials could be labelled as ‘compost’ by retailers and suppliers. We investigated six different amendments currently used, or available for use, in horticulture: composted bark, composted bracken, spent mushroom compost, composted horse manure, garden waste compost (at two different application rates), and peat. Using a controlled field experiment, we examined the physicochemical differences between the amendments, the subsequent effects on soil characteristics, and resultant yield and biometrics of Lavatera trimiestris. Amended soils resulted in a significantly different multivariate soil environment and N budget when compared to the unamended control. However, the effect on yield and plant biometrics (number of flowers, plant height, etc.) depended on the amendment used. Application of garden compost resulted in up to a five-fold increase in yield. However, there was no significant difference in yields in soils amended with composted bark or peat, when compared to the unamended control. This has implications, as there is increasing pressure to remove peat from products available to domestic gardeners. The variability in the different amendments investigated in our research, in addition to the variable effects on plant growth parameters, suggests that repeated use of a single amendment may not be best practise for gardeners.

HortScience ◽  
2006 ◽  
Vol 41 (5) ◽  
pp. 1332-1338 ◽  
Author(s):  
Sean M. Westerveld ◽  
Alan W. McKeown ◽  
Mary Ruth McDonald

An understanding of nitrogen (N) uptake and the partitioning of N during the season by the carrot crop (Daucus carota subsp. sativus [Hoffm.] Arkang.) is required to develop more efficient N fertilization practices. Experiments were conducted on both organic and mineral soils to track the accumulation of dry matter (DM) and N over the growing season and to develop an N budget of the crop. Treatments included two carrot cultivars (`Idaho' and `Fontana') and 5 N rates ranging from 0% to 200% of the provincial recommendations in Ontario. Foliage and root samples were collected biweekly from selected treatments during the growing season and assessed for total N concentration. Harvest samples were used to calculate N uptake, N in debris, and net N removal values. Accumulation of DM and N in the roots was low until 50 to 60 days after seeding (DAS) and then increased linearly until harvest for all 3 years regardless of the soil type, cultivar, and N rate. Foliage dry weight and N accumulation were more significant by 50 to 60 DAS, increased linearly between 50 and 100 DAS, and reached a maximum or declined slightly beyond 100 DAS in most cases. The N application rates required to maximize yield on mineral soil resulted in a net loss of N from the system, except when sufficient N was available from the soil to produce optimal yield. On organic soil, a net removal of N occurred at all N application rates in all years. Carrots could be used as an N catch crop to reduce N losses in a vegetable rotation in conditions of high soil residual N, thereby improving the N use efficiency (NUE) of the crop rotation.


SLEEP ◽  
2021 ◽  
Vol 44 (Supplement_2) ◽  
pp. A287-A288
Author(s):  
Joey W Chan ◽  
Y K Wing ◽  
S P Lam ◽  
Shirley Xin Li ◽  
J Zhang

Abstract Introduction Drop out during treatment hampers therapeutic effect of interventions. The current study examines the possible predictors of drop out during the five-week light treatment in patients with unipolar non-seasonal depression and evening-chronotype. Methods Baseline characteristics including demographics, sleep diary parameters, light treatment prescribed, and early clinical outcomes changes were compared between the Drop out and Non drop out group. Logistic regression analysis was used to examine predictors for drop out. All data were analyzed in a modified intention to treat analysis with last observation carried forward approach. Results A total of 91 subjects (Female 79%, 46.3 ± 11.8 years old) were included in the analysis. There was no significant difference in the baseline demographic and clinical characteristics between the Drop out and Non drop out group. There was also no significant difference in the improvement of clinical parameters over the first week among the two groups. However, treatment non-adherence (in terms of compliance of less than 80% of prescribed duration) over the first treatment week predicts a five-fold increase in risk of drop out during light therapy. (OR: 5.85, CI: 1.414–24.205, p=0.015) after controlling for potential confounders including age, gender, treatment group, patient expectation, and treatment-emergent adverse events. Conclusion This study found that baseline clinical characteristics including depression severity and improvement of depressive symptoms in the initial week did not differ between the Drop out and Non drop out group. The drop out was also not affected by the type of light (dim red versus bright red light), indirectly supporting dim red light as a valid placebo in bright light therapy trial. Treatment adherence is the early phase of light treatment is an important predictor of drop out. Support (if any):


1995 ◽  
Vol 46 (3) ◽  
pp. 583 ◽  
Author(s):  
RJQ Tarr

Growth rates of a number of Haliotis midae populations around the South African coast were studied by means of tagging. These populations ranged from the cool waters of the western coast to the more temperate environment of the eastern Cape. Standard von Bertalanffy growth curves were fitted and growth parameters derived. These ranged from 0.19 to 0.25 for K, the average rate at which L∞ is approached, and from 156 to 173 for L∞, the average theoretical maximum length. These indicate far higher growth rates than were previously published for this commercially fished species, and the reasons for this difference are discussed. The expectation that growth rates would be fastest in the warmer eastern Cape waters was not realized, there being no significant difference in growth between the Bird Island population on the eastern coast and the Robben Island population on the western coast. These new growth parameters indicate that H. midae in the commercial fishery grounds is attaining sexual maturity some four years earlier, and the minimum legal size some five years earlier, than previously considered. This has considerable significance for modelling studies presently underway. Movement of a small population of adult H. midae was studied over a three-year period, after which 47% of the original abalone were still present on the study site. Of these, 81.5% still occupied exactly the same position on the rocks. This indicates that H. midae that have located an optimum habitat, and that are not disturbed, tend not to move.


2016 ◽  
Vol 70 (1) ◽  
pp. 69-74 ◽  
Author(s):  
Jonathan Joseph Scargill ◽  
John Mark Guy

AimsMany clinical laboratories in the UK use a standard equation to adjust total calcium for albumin concentration. To assess the validity of this practice, we assessed the effect of the use of a traditional and locally derived calcium adjustment equation on parathyroid hormone (PTH) and 25(OH, hydroxy) vitamin D levels.MethodsSamples requested for calcium and albumin measurement over a 6 month period that met inclusion criteria were used to derive a calcium adjustment equation (n=60 941). The traditional and locally derived calcium adjustment equations were then applied to a second cohort of adult patients that underwent calcium measurement over a 1 year period (n=275 456). Patients were classified as hypocalcaemic, normocalcaemic or hypercalcaemic using a UK Pathology Harmony adjusted calcium reference interval (2.2–2.6 mmol/L).ResultsThe local calcium adjustment equation provided a 7.1-fold reduction in the prevalence of hypocalcaemia. Patients classified as hypocalcaemic using the locally derived equation had statistically significantly lower 25(OH) vitamin D and higher PTH levels. A 2.4-fold increase in the prevalence of hypercalcaemia was also observed using the new equation, but with no significant difference in 25(OH) vitamin D or PTH levels.ConclusionsA locally derived calcium adjustment equation reclassified the calcium status of 61 278 (22%) patients. Patients classified as hypocalcaemic by the locally derived equation had significantly lower 25(OH) vitamin D and significantly higher PTH values, providing evidence that use of this adjustment equation generates adjusted calcium results of greater clinical relevance. This study provides further and novel evidence that individual laboratories should determine local equations for adjusted calcium where possible.


2006 ◽  
Vol 43 (4) ◽  
pp. 305-309
Author(s):  
Camila Carbone Prado ◽  
Roberto José Negrão Nogueira ◽  
Antônio de Azevedo Barros-Filho ◽  
Elizete Aparecida Lomazi da Costa-Pinto ◽  
Gabriel Hessel

BACKGROUD: Chronic liver diseases in childhood often cause undernutrition and growth failure. To our knowledge, growth parameters in infants with neonatal cholestasis are not available AIM: To evaluate the nutritional status and growth pattern in infants with intrahepatic cholestasis and extrahepatic cholestasis. PATIENTS AND METHODS: One hundred forty-four patients with neonatal cholestasis were followed up at the Pediatric Gastroenterology Service of the Teaching Hospital, State University of Campinas, Campinas, SP, Brazil, in a 23-year period, from 1980 to 2003. The records of these patients were reviewed and patients were classified into two groups, according to their anatomical diagnosis: patients with intrahepatic cholestasis - group 1, and patients with extrahepatic cholestasis - group 2. Records of weight and height measurements were collected at 4 age stages of growth, in the first year of life: 1) from the time of the first medical visit to the age of 4 months (T1); 2) from the 5th to the 7th month (T2); 3) from the 8th to the 10th month (T3); and 4) from the 11th to the 13th month (T4). The weight-by-age and height-by-age Z-scores were calculated for each patient at each stage. In order for the patient to be included in the study it was necessary to have the weight and/or height measurements at the 4 stages. Analyses of variance and Tukey's tests were used for statistical analysis. Repeated measurement analyses of variance of the weight-by-age Z-score were performed in a 60-patient sample, including 29 patients from group 1 and 31 patients from group 2. The height-by-age data of 33 patients were recorded, 15 from group 1 and 18 from group 2 RESULTS: The mean weight-by-age Z-scores of group 1 patients at the 4 age stages were: T1=-1.54; T2=-1.40; T3=-0.94; T4=-0.78. There was a significant difference between T2 X T3 and T1 X T4. The weight-by-age Z-scores for group 2 patients were :T1=-1.04; T2=-1.67; T3=-1.93 and T4=-1.77, with a significant difference between T1 X T2 and T1 X T4. The mean weight-by-age Z-scores also showed a significant difference between group 1 and group 2 at stages T3 and T4. The mean height-by-age Z-scores at the four stages in group 1 were: T1=-1.27; T2=-1.16; T3=-0.92 and T4=-0.22, with a significant difference between T3XT4 and T1XT4. The scores for group 2 patients were: T1=-0.93; T2=-1.89; T3=-2.26 and T4=-2.03, with a significant difference between T1XT2 and T1XT4. The mean height-by-age Z-scores also showed a significant difference between group 1 and group 2 at T3 and T4 CONCLUSION: The weight and height differences between the groups became significant from the 3rd measurement onward, with the most substantial deficit found in the extrahepatic group. In this group, there is evidence that the onset of weight and height deficit occurs between the first and second evaluation stages.


2020 ◽  
Author(s):  
Robert M. Moldwin ◽  
Vishaan Nursey ◽  
Oksana Yaskiv ◽  
Siddhartha Dalvi ◽  
Michael Funaro ◽  
...  

AbstractAimsTo quantify the number of immune cells in the bladder urothelium and concentrations of urinary cytokines in patients with Interstitial Cystitis/Bladder Pain Syndrome (IC/BPS). To identify differences in these measures in IC/BPS patients with Hunner’s lesions (IC/BPS-HL) and without Hunner’s lesions (IC/BPS-NHL).MethodsBladder tissue biopsies were obtained from 48 patients with IC/BPS-HL and unaffected controls (UC) and stained with antibodies for various immune cell markers such as CD138, CD20 and CD56. Levels of cytokines (Interferon (IFN)-γ, Interleukin (IL)-1β, IL-2, IL- 4, IL-6, IL-8, IL12P70, IL-13, and TNF-α) were measured from normalized urine obtained from 18 IC/BPS-HL, 18 IC/BPS-NHL, and 4 UC.ResultsNumbers of CD138+ plasma cells, CD20+ B cells, and CD3+ T cells were significantly increased (50 fold, 30 fold, and an almost 3 fold increase, respectively; p-values: 1.34E-06, 3.26E-04, and 2.52E-6) in the bladders of IC/BPS-HL patients compared to UC. Patients with IC/BPS-HL had significantly elevated urinary levels of IL-6 (p=0.0028) and TNF-α (p=0.009) compared to patients with IC/BPS-NHL and UC. In contrast, IL-12p70 levels were significantly higher in the patients with IC/BPS-NHL than in HL patients (p=0.033). No significant difference in IL-12p70 levels were observed between IC/BPS-HL and UC.ConclusionDifferent cytokines were elevated in the urine of IC/BPS patients with and without HL, suggesting differences in underlying disease processes. Elevated levels of CD138+, CD20+, and CD3+ cells in HL indicate B and T-cell involvement in lesion formation. Determining which cytokines and immunological pathways are present in IC/BPS-HL could elucidate the disease mechanism.


2021 ◽  
pp. 56-62
Author(s):  
Theophilus Apenuvor ◽  
John Blay ◽  
Joseph Aggreyfynn ◽  
Simon Drafor

Over-population and stunted growth had been major challenges in the culture of tilapia. The use of synthetic androgen 17- α Methyl Testosterone (MT) was a breakthrough. However, its optimum level towards effective masculinization and growth is a concern. The aim of this research was to ascertain the optimum level of MT towards effective all-male population production and growth of Black-Chinned tilapia. In the present study, the effect of different dose rates of synthetic androgen 17-α Methyl Testosterone (MT) i.e., 0, 30, 60, and 120 mg of the hormone per kg of feed on sex, growth, and condition of Black-Chinned tilapia was evaluated. MT was administered orally by using powdered dry starter feed (Crude Protein 40 %) and Ethanol. The fry was fed for 30 days in the experimental tanks. At the end of the experiment, the sex ratios were determined by examining the operculum coloration as a means of sex identification. Growth performance was monitored by measuring and recording the morphometric characteristics. Bodyweight and total length of the fish on the start of feeding, end of feeding (one month sex reversal period), and two months after feeding were measured. The results of the present study showed that all MT receiving treatment showed a significantly higher male proportion than the control (0 mg MT/kg feed individuals). In all MT treatments groups, the control expects the 30 mg MT/kg in feed individuals’ deviate significantly from the normal 1:1 sex ratio (Chi-square analysis). The dose rate of 120 mg MT /kg feed resulted in the maximum male population (92.7%). Hence, for an effective high percentage of all-male population production in Black-Chinned tilapia, 120 mg MT /kg in feed is recommended. In terms of growth and condition factor, all the individual treatments, as well as the control, showed no significant difference. All the treated individuals showed similar condition factors during the pre and post-treatment, however, the individuals treated with 30 mg MT /kg feed exhibited better condition during the pre-treatment than the post-treatment period. Temperature, pH and dissolved oxygen recorded in this study were within the desirable limit for tilapia.


2020 ◽  
Vol 6 (2) ◽  
pp. 258-261
Author(s):  
Md. Ariff Farah Fazwa ◽  
Saffie Norhayati ◽  
Samsul Bahari Syafiqah Nabilah ◽  
Sundara Rajoo Keeren

Labisia pumila, locally known in Malaysia as Kacip Fatimah, is highly-prized for its phenols. Phenolic compounds in L. pumila has numerous pharmacological properties such as having anti-oxidant, anti-microbial, anti-inflammatory and anti-cancer potential. The production of phenolic contents in plants is influence by various factor, including abiotic factors such as soil properties. Thus, the objective of this study was to determine the effects of different combinations of growing media on the growth and total phenolic content in L. pumila leaves. Six combinations of growing media were used, each using different types of compost that had differing amounts of L. pumila leaves. The plants were grown in all media for a period of six months at FRIM’s nursery. Besides growth performance, the total phenolic content was also determined, six months after planting. There was no significant difference in growth parameters for all treatments, with the exception of control (significantly lower than all treatments). However, the total phenolic content of Treatment 1 (80.6 mg GAE/g) was significantly higher than all other treatments. This can be attributed to the properties of Compost 1 (which was in the growth media of Treatment 1), as it had the highest pH (5.26), the highest potassium concentration (0.7%) and high nitrogen concentrations (1.32%). The composition of Compost 1 was 5 kg dry leaves + 500 g dry Kacip Fatimah + Slow Release Fertilizer (SRF). Results from this study showed that growing media is a key factor that leads to significant increment in phenolic compounds in L. pumila.


2021 ◽  
Vol 25 (8) ◽  
pp. 1547-1550
Author(s):  
O.A. Majekodunmi ◽  
I.O. Abiola ◽  
A.M. Aderemi ◽  
J.O. Adedipe ◽  
O.G. Ogunwale ◽  
...  

This study investigated the effect of sowing media on the seed germination and subsequent seedling growth of Senna fistula L. Treatments were T1 (Top soil), T2 (River sand), T3 (Grinded coconut husk) and T4 (weathered sawdust), replicated two times for seed germination. The treatments were arranged in a Completely Randomized Design (CRD) and the data generated was subjected to analysis of variance (ANOVA) at 5% level of significance, while mean separation where appropriate was done using Least Significant Difference (LSD). The different sowing media used had positive effect on the seed emergence, the seeds planted in river sand had the highest emergence percentage of 70%. The different sowing media used did not have any significant effect on the vegetative growth parameters, statistically, they had same effect on the parameters measured. Nonetheless, seedlings from river sand produced highest number of leave (20.4), seedlings from topsoil produced highest plant height and largest leaf area of l0.62 cm and 37.l4 cm2 respectively. The seedlings from weathered sawdust produced the highest stem diameter of 0.79 mm, while seedlings from grinded coconut husk had lowest values for all the growth parameters measured. Therefore, it is recommended that river sand or weathered sawdust can be used to propagate Senna fistula seeds.


2001 ◽  
Vol 10 (Supplement) ◽  
Author(s):  
K. SAIJONKARI-PAHKALA

This study was begun in 1990 when there was a marked shortage of short fibre raw material for the pulp industry. During the last ten years the situation has changed little, and the shortage is still apparent. It was estimated that 0.5 to 1 million hectares of arable land would be set aside from cultivation in Finland during this period. An alternative to using hardwoods in printing papers is non-wood fibres from herbaceous field crops. The study aimed at determining the feasibility of using non-wood plants as raw material for the pulp and paper industry, and developing crop management methods for the selected species. The properties considered important for a fibre crop were high yielding ability, high pulping quality and good adaptation to the prevailing climatic conditions and possibilities for low cost production. A strategy and a process to identify, select and introduce a crop for domestic short fibre production is described in this thesis. The experimental part of the study consisted of screening plant species by analysing fibre and mineral content, evaluating crop management methods and varieties, resulting in description of an appropriate cropping system for large-scale fibre plant production. Of the 17 herbaceous plant species studied, monocotyledons were most suitable for pulping. They were productive and well adapted to Finnish climatic conditions. Of the monocots, reed canary grass (Phalaris arundinacea L.) and tall fescue (Festuca arundinacea Schreb.) were the most promising. These were chosen for further studies and were included in field experiments to determine the most suitable harvesting system and fertilizer application procedures for biomass production. Reed canary grass was favoured by delayed harvesting in spring when the moisture content of the crop stand was 10-15% of DM before production of new tillers. When sown in early spring, reed canary grass typically yielded 7-8 t ha-1 within three years on clay soil. The yield exceeded 10 t ha-1 on organic soil after the second harvest year. Spring harvesting was not suitable for tall fescue and resulted in only 37-54% of dry matter yields and in far fewer stems and panicles than harvested during the growing season. The economic optimum for fertilizer application rate for reed canary grass ranged from 50 to 100 kg N ha-1 when grown on clay soil and harvested in spring. On organic soil the fertilizer rates needed were lower. If tall fescue is used for raw material for paper, fertilizer application rates higher than 100 kg N ha-1 were not of any additional benefit. It was possible to decrease the mineral content of raw material by harvesting in spring, using moderate fertilizer application rates, removing leaf blades from the raw material and growing the crop on organic soil. The fibre content of the raw material increased the later the crop was harvested, being highest in spring. Removing leaf blades and using minimum fertilizer application rates in-creased the fibre content of biomass.;


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