scholarly journals Effects of a Trench as a Moisture Harvesting Structure on the Biomass Production and Growth of Trees Planted to Restore Degraded Land, Southern Ethiopia

2020 ◽  
Vol 10 (23) ◽  
pp. 8560
Author(s):  
Shiferaw Alem ◽  
Petr Němec ◽  
Hana Habrová
Keyword(s):  
Biomass Production ◽  
Rainwater Harvesting ◽  
Biomass Productivity ◽  
Southern Ethiopia ◽  
Total Biomass ◽  
Acacia Saligna ◽  
Degraded Land ◽  
The Mean ◽  
The Individual ◽  
Species Specific

Knowledge about the biomass productivity of trees planted in a rainwater harvesting structure, i.e., a trench (T), relative to a normal pit (P) on degraded land is scarce. The objective of this research paper is to compare the effect of T with P on the growth and biomass production of the Acacia saligna and Casuarina equisetifolia which were planted on degraded land. All the individual stems of both species in the T and P, their diameters at breast height (DBH) and heights in 2016 and 2020 were measured. Species-specific allometric equations were used to quantify the biomass production of the studied species. The t-tests were used for data analysis; both A. saligna and C. equisetifolia individuals planted in the T had higher DBH and height increment as compared with A. saligna and C. equisetifolia that were planted and grown in a P. The results also revealed significant differences on the mean DBH and height of A. saligna and C. equisetifolia planted in a T and P (p < 0.05). Between 2016 and 2020, the total biomass (TB) of A. saligna planted in a T and in a P increased significantly (p < 0.05) on average by 25.5 kg/tree and 7.7 kg/tree, respectively (p < 0.05). Similarly, the mean TB values of the C. equisetifolia planted in a T and a P between 2016 and 2020 increased significantly (p < 0.05) by 28.9 kg/tree and 13.1 kg/tree, respectively. Finally, establishing trenches to restore degraded lands was shown to facilitate growth and biomass production of planted species on degraded land.

scholarly journals Treatment and Re-Use of Raw Blackwater by Chlorella vulgaris-Based System

Water ◽  
2020 ◽  
Vol 12 (10) ◽  
pp. 2660
Author(s):  
Marco Antonio Segovia Bifarini ◽  
Miha Žitnik ◽  
Tjaša Griessler Bulc ◽  
Aleksandra Krivograd Klemenčič
Keyword(s):  
Biomass Production ◽  
Chlorella Vulgaris ◽  
Nutrient Removal ◽  
Liquid Waste ◽  
Oxygen Demand ◽  
Biomass Productivity ◽  
Dry Weight ◽  
Nutrient Content ◽  
Total Biomass ◽  
Sanitation Systems

In this study, we examined a Chlorella vulgaris-based system as a potential solution to change liquid waste, such as blackwater, into valuable products for agriculture while protecting waters from pollution without technical demanding pre-treatment. To evaluate the possibility of nutrient removal and biomass production from raw blackwater, four blackwater dilutions were tested at lab-scale: 50%, 30%, 20%, and 10%. The results showed that even the less diluted raw blackwater was a suitable growth medium for microalgae C. vulgaris. As expected, the optimum conditions were observed in 10% blackwater with the highest growth rate (0.265 d−1) and a nutrient removal efficiency of 99.6% for ammonium and 33.7% for phosphate. However, the highest biomass productivity (5.581 mg chlorophyll-a L−1 d−1) and total biomass (332.82 mg dry weight L−1) were achieved in 50% blackwater together with the highest chemical oxygen demand removal (81%) as a result of the highest nutrient content and thus prolonged growth phase. The results suggested that the dilution factor of 0.5 followed by microalgae cultivation with a hydraulic retention time of 14 days could offer the highest biomass production for the potential use in agriculture and, in parallel, a way to treat raw blackwater from source-separation sanitation systems.

Sustainable Cultivation of Desmodesmus armatus SAG276.4d using Leachate as a Growth Supplement for Simultaneous Biomass Production and CO2 Fixation

2021 ◽  
Vol 10 (4) ◽  
pp. 865-873
Author(s):  
Muhammad Taufiq Kamal Fuad ◽  
Azianabiha A Halip Khalid ◽  
Kamrul Fakir Kamarudin
Keyword(s):  
Growth Rate ◽  
Biomass Production ◽  
Carbon Fixation ◽  
Growth Parameters ◽  
Biomass Productivity ◽  
Total Biomass ◽  
Microalgae Cultivation ◽  
Freshwater Microalgae ◽  
Light Duration ◽  
Carbon Dioxide Co2

Microalgae cultivation has been identified to be highly beneficial for the production of valuable biomass. The recent worldwide interest is to cultivate microalgae in wastewater to replace the use of expensive commercial media. Microalgae can utilize nutrients from the wastewater for their biomass growth, which is useful as feedstock in many products. Interestingly, microalgae cultivation is also capable of reducing a greenhouse gas due to absorption of carbon dioxide (CO2) during photosynthesis. This study was conducted to study the growth of microalgae using leachate as a nutrient supplement. The scope of the research involved the cultivation of freshwater microalgae, Desmodesmus armatus, in the synthetics medium with various percentages of leachate under different light exposures. The growth parameters such as the specific growth rate, biomass productivity, and cell division time were used to evaluate the microalgae growth performance. The amount of CO2 absorbed during the cultivation was determined based on the total biomass production. The highest growth rate of 0.423/day was achieved using a 5% leachate medium under 12 h light duration, and the highest carbon fixation of 1.317 g CO2/L/day was calculated using a culture supplemented with 5% leachate with 24 h light period. The high presence of nutrients in the leachate has contributed to the growth of the microalgae; thus, it has great potential as an alternative growth medium to support biomass production and subsequently help to mitigate global warming.

scholarly journals The effect of bottom sediment on biomass production by Italian ryegrass and maize

2007 ◽  
Vol 9 (4) ◽  
pp. 48-51 ◽  
Author(s):  
Barbara Wiśniowska-Kielian
Keyword(s):  
Bottom Sediment ◽  
Biomass Production ◽  
Plant Biomass ◽  
Lolium Multiflorum ◽  
Acid Soil ◽  
Italian Ryegrass ◽  
Composition Analysis ◽  
Individual Plant ◽  
Total Biomass ◽  
The Individual

The effect of bottom sediment on biomass production by Italian ryegrass and maize A two-year pot experiment (2005 and 2006) was conducted to estimate an effect of dredged bottom sediment from Rożnów Reservoir addition to the light, very acid soil on the plant biomass production. The sediment was applied in the amount from 1 to 20% of the substratum mass. Italian ryegrass (Lolium multiflorum L.) and maize (Zea mays L.) were cultivated as the successive test plants. The lowest amount of plant biomass was obtained on the soil (control) and each sediment addition to the substratum caused an increase of the biomass production, both tops as well as the roots of the plant. Larger sediment additions (7% and more) caused a significant increase of the yield, of both the individual plant species and the total biomass during the two years of the experiment. The bottom sediment added to the light, very acid soil distinctly improved the plant yielding and the way of biomass utilisation should be assessed on the basis of its chemical composition analysis.

scholarly journals Parent stand age and harvesting treatment effects on juvenile aspen biomass productivity

1995 ◽  
Vol 71 (3) ◽  
pp. 299-303 ◽  
Author(s):  
H. Grewal
Keyword(s):  
Biomass Production ◽  
Treatment Effects ◽  
Biomass Productivity ◽  
Stand Age ◽  
Total Biomass ◽  
Biomass Removal ◽  
Biomass Component ◽  
Young Parent ◽  
Branch Biomass ◽  
Harvest Method

The objectives of this study were to characterize parent stand age and harvest method treatment effects on biomass production of aspen and other species, and to construct equations for the prediction of aspen stemwood, branch, and foliage biomass production. Aspen from young parent stands (30–40 years) generally regenerated taller and denser stands, and produced higher total aspen biomass and larger proportions of branch biomass than those regenerated from older parent stands. Stands regenerated after total biomass removal were taller and had larger diameters and average densities than stands regenerated by conventional logging. Aspen biomass component production was predicted consistently by various combinations and transformations of height and diameter. Key words: aspen, biomass equations, biomass production, harvest method, logging method, parent age

Relation Between Production and Biomass

1971 ◽  
Vol 28 (10) ◽  
pp. 1573-1581 ◽  
Author(s):  
K. Radway Allen
Keyword(s):  
Life Span ◽  
Simple Relation ◽  
Annual Production ◽  
Total Biomass ◽  
Total Production ◽  
Animal Populations ◽  
The Mean ◽  
Biomass Ratio ◽  
The Individual ◽  
Simple Growth

A series of mathematical models of cohorts in animal populations representing various combinations of several different simple growth and mortality functions is examined to investigate the ratio between mean biomass and production over unit time, and to compare this ratio with the mean age and mean life span of the animals in the cohort.For any cohort, the ratio of production per unit time to mean biomass is equal to the ratio of total production by the cohort to its total biomass integral by time. For populations consisting of a number of simultaneous, successive, or overlapping cohorts, the ratio of production per unit time to mean biomass is equal to the mean of the ratios for the individual cohorts weighted by the mean biomasses of the cohorts.If the cohorts are identical, the population ratio is the same as the cohort ratio and problems arising from the presence of more than one cohort may be ignored. Formulations for the total production per cohort, biomass integral, and, where they can be simplified, their ratios, are given.Comparison with mean age and mean life span shows that for constant exponential mortality, mean age and mean life span are both equal to the reciprocal of the production–biomass ratio. For other mortality functions, if growth in weight is linear, the production–biomass ratio equals the reciprocal of the mean age. For other models there is no simple relation. In general, mean age appears a better approximation than mean life span to the reciprocal of the production–biomass ratio.These methods are applied, as an example, to Antarctic krill, using a model having linear growth in length and four periods with different exponential mortality rates. For this model, annual production is 1.8 times the mean biomass so that assumption of equality leads to an underestimate of production. Mean age and mean life span are 0.21 and 0.037 years respectively. Thus, use of either of these as an approximation, and particularly mean life span, leads to severe overestimation of annual production.

A Simple Method for the Evaluation of Internal Doses in Nuclear Medicine

1974 ◽  
Vol 13 (02) ◽  
pp. 193-206
Author(s):  
L. Conte ◽  
L. Mombelli ◽  
A. Vanoli
Keyword(s):  
Nuclear Medicine ◽  
Close Agreement ◽  
Whole Body ◽  
Simple Method ◽  
Rapid Estimation ◽  
Absorbed Doses ◽  
The Mean ◽  
The Individual ◽  
Estimation Of Risk

SummaryWe have put forward a method to be used in the field of nuclear medicine, for calculating internally absorbed doses in patients. The simplicity and flexibility of this method allow one to make a rapid estimation of risk both to the individual and to the population. In order to calculate the absorbed doses we based our procedure on the concept of the mean absorbed fraction, taking into account anatomical and functional variability which is highly important in the calculation of internal doses in children. With this aim in mind we prepared tables which take into consideration anatomical differences and which permit the calculation of the mean absorbed doses in the whole body, in the organs accumulating radioactivity, in the gonads and in the marrow; all this for those radionuclides most widely used in nuclear medicine. By comparing our results with dose obtained from the use of M.I.R.D.'s method it can be seen that when the errors inherent in these types of calculation are taken into account, the results of both methods are in close agreement.

SERUM THYROTROPHIN AND THE RESPONSE TO THYROTROPHIN RELEASING HORMONE IN SYMPTOMLESS AUTOIMMUNE THYROIDITIS AND IN BORDERLINE AND OVERT HYPOTHYROIDISM

1974 ◽  
Vol 75 (2) ◽  
pp. 274-285 ◽  
Author(s):  
A. Gordin ◽  
P. Saarinen ◽  
R. Pelkonen ◽  
B.-A. Lamberg
Keyword(s):  
Autoimmune Thyroiditis ◽  
Elevated Serum ◽  
Mean Value ◽  
Primary Hypothyroidism ◽  
Overt Hypothyroidism ◽  
Thyrotrophin Releasing Hormone ◽  
Releasing Hormone ◽  
The Mean ◽  
The Individual ◽  
Serum Tsh

ABSTRACT Serum thyrotrophin (TSH) was determined by the double-antibody radioimmunoassay in 58 patients with primary hypothyroidism and was found to be elevated in all but 2 patients, one of whom had overt and one clinically borderline hypothyroidism. Six (29%) out of 21 subjects with symptomless autoimmune thyroiditis (SAT) had an elevated serum TSH level. There was little correlation between the severity of the disease and the serum TSH values in individual cases. However, the mean serum TSH value in overt hypothyroidism (93.4 μU/ml) was significantly higher than the mean value both in clinically borderline hypothyroidism (34.4 μU/ml) and in SAT (8.8 μU/ml). The response to the thyrotrophin-releasing hormone (TRH) was increased in all 39 patients with overt or borderline hypothyroidism and in 9 (43 %) of the 21 subjects with SAT. The individual TRH response in these two groups showed a marked overlap, but the mean response was significantly higher in overt (149.5 μU/ml) or clinically borderline hypothyroidism (99.9 μU/ml) than in SAT (35.3 μU/ml). Thus a normal basal TSH level in connection with a normal response to TRH excludes primary hypothyroidism, but nevertheless not all patients with elevated TSH values or increased responses to TRH are clinically hypothyroid.

Quality of Life for Children with Persistent Sinonasal Symptoms

2003 ◽  
Vol 128 (1) ◽  
pp. 17-26 ◽  
Author(s):  
David J. Kay ◽  
Richard M. Rosenfeld
Keyword(s):  
Quality Of Life ◽  
Clinical Care ◽  
Longitudinal Change ◽  
Good Test ◽  
Routine Clinical Care ◽  
Before And After ◽  
The Mean ◽  
The Individual ◽  
Sinonasal Symptoms

OBJECTIVE: The goal was to validate the SN-5 survey as a measure of longitudinal change in health-related quality of life (HRQoL) for children with persistent sinonasal symptoms. DESIGN AND SETTING: We conducted a before and after study of 85 children aged 2 to 12 years in a metropolitan pediatric otolaryngology practice. Caregivers completed the SN-5 survey at entry and at least 4 weeks later. The survey included 5 symptom-cluster items covering the domains of sinus infection, nasal obstruction, allergy symptoms, emotional distress, and activity limitations. RESULTS: Good test-retest reliability ( R = 0.70) was obtained for the overall SN-5 score and the individual survey items ( R ≥ 0.58). The mean baseline SN-5 score was 3.8 (SD, 1.0) of a maximum of 7.0, with higher scores indicating poorer HRQoL. All SN-5 items had adequate correlation ( R ≥ 0.36) with external constructs. The mean change in SN-5 score after routine clinical care was 0.88 (SD, 1.19) with an effect size of 0.74 indicating good responsiveness to longitudinal change. The change scores correlated appropriately with changes in related external constructs ( R ≥ 0.42). CONCLUSIONS: The SN-5 is a valid, reliable, and responsive measure of HRQoL for children with persistent sinonasal symptoms, suitable for use in outcomes studies and routine clinical care.

Suppression of Weed Occurrence in a Five-year Corn-earthworm Coculture System

Weed Science ◽  
2020 ◽  
pp. 1-23
Author(s):  
Tao Li ◽  
Jiequn Fan ◽  
Zhenguan Qian ◽  
Guohui Yuan ◽  
Dandan Meng ◽  
...  
Keyword(s):  
Weed Species ◽  
Ecological Benefits ◽  
Economic Output ◽  
Green Foxtail ◽  
Weed Diversity ◽  
The Mean ◽  
Common Purslane ◽  
Species Specific ◽  
Density And Biomass ◽  
Successive Experiment

Abstract The use of a corn-earthworm coculture (CE) system is an eco-agricultural technology that has been gradually extended due to its high economic output and diverse ecological benefits for urban agriculture in China. However, the effect of CE on weed occurrence has received little attention. A five-year successive experiment (2015 to 2019) was conducted to compare weed occurrence in CE and a corn (Zea mays L.) monoculture (CM). The results show that CE significantly decreased weed diversity, the dominance index, total weed density and biomass, but increased the weed evenness index. The five-year mean number of weed species per plot was 8.4 in CE and 10.7 in CM. Compared to those in CM, the five-year mean density and biomass of total weeds in CE decreased by 59.2% and 66.6%, respectively. The effect of CE on weed occurrence was species specific. The mean density of large crabgrass [Digitaria sanguinalis (L.) Scop.], green foxtail [Setaria viridis (L.) Beauv.], goosegrass [Eleusine indica (L.) Gaertn.], and common purslane (Portulaca oleracea L.) in CE decreased by 94.5, 78.1, 75.0, and 45.8%, whereas the mean biomass decreased by 96.2, 80.8, 76.9, and 41.4%, respectively. Our study suggests that the use of CE could suppress weed occurrence and reduce herbicide inputs in agriculture.

Contrasting yield formation characteristics in two super-rice hybrids that differ in growth duration

2021 ◽  
pp. 1-10
Author(s):  
Min Huang ◽  
Zui Tao ◽  
Tao Lei ◽  
Fangbo Cao ◽  
Jiana Chen ◽  
...  
Keyword(s):  
Solar Radiation ◽  
Biomass Production ◽  
Field Experiments ◽  
Crop Improvement ◽  
Total Biomass ◽  
Growth Duration ◽  
Area Index ◽  
Rice Hybrid ◽  
Use Efficiency ◽  
Yield Formation

Summary The development of high-yielding, short-duration super-rice hybrids is important for ensuring food security in China where multiple cropping is widely practiced and large-scale farming has gradually emerged. In this study, field experiments were conducted over 3 years to identify the yield formation characteristics in the shorter-duration (∼120 days) super-rice hybrid ‘Guiliangyou 2’ (G2) by comparing it with the longer-duration (∼130 days) super-rice hybrid ‘Y-liangyou 1’ (Y1). The results showed that G2 had a shorter pre-heading growth duration and consequently a shorter total growth duration compared to Y1. Compared to Y1, G2 had lower total biomass production that resulted from lower daily solar radiation, apparent radiation use efficiency (RUE), crop growth rate (CGR), and biomass production during the pre-heading period, but the grain yield was not significantly lower than that of Y1 because it was compensated for by the higher harvest index that resulted from slower leaf senescence (i.e., slower decline in leaf area index during the post-heading period) and higher RUE, CGR, and biomass production during the post-heading period. Our findings suggest that it is feasible to reduce the dependence of yield formation on growth duration to a certain extent in rice by increasing the use efficiency of solar radiation through crop improvement and also highlight the need for a greater fundamental understanding of the physiological processes involved in the higher use efficiency of solar radiation in super-rice hybrids.

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