Resource Management Biology for the Edible Kelp Cymathere triplicata

1984 ◽  
Vol 41 (2) ◽  
pp. 271-277 ◽  
Author(s):  
William G. Roland
Keyword(s):  
Resource Management ◽  
Moisture Content ◽  
Recovery Rate ◽  
Standing Crop ◽  
Control Area ◽  
Spore Production ◽  
Basal Part ◽  
Full Recovery ◽  
Overwinter Mortality

Sporophytes of Cymathere triplicata appeared only in spring and density declined thereafter; overwinter mortality was 100%. Standing crop estimates were highest during May–July. Plants were heaviest and generally had the longest and widest laminae in July and August. Thickness of laminae increased through December, the greatest increase being in the basal part of the lamina. Sori were initiated in August and approximately 90% of plants were fertile by September. Epibiota were most abundant during August–October. Moisture content decreased 2–3% from spring through winter. A plot subjected to almost total harvest in August had approximately 50% recovery of standing crop after 1 yr and full recovery after 2 yr, compared with a control area. A comparable recovery rate was seen for a similar September harvest. Sustained yields for a region of coastline should be maintained if no more than 50% of the standing crop is removed by intensive harvesting within plots, and if harvesting is not allowed prior to spore production. Best quality laminae in terms of length, thickness, weight per area, and moisture content occurred in August and September.

Postharvest recovery of beds of the edible red alga Porphyra perforata

1984 ◽  
Vol 62 (9) ◽  
pp. 1968-1970 ◽  
Author(s):  
William G. Roland ◽  
L. Michael Coon
Keyword(s):  
Standing Crop ◽  
Negative Impact ◽  
Control Area ◽  
Percent Cover ◽  
Annual Fluctuation ◽  
Queen Charlotte Islands ◽  
Negative Effect ◽  
Large Plot ◽  
Small Plot ◽  
Whole Plants

Recovery of intertidal Porphyra beds following hand harvest was studied near the northwest tip of the Queen Charlotte Islands, B.C. Twenty-six percent of the standing crop of Porphyra perforata J. Ag. was removed in a large plot in June 1981; no negative effect on standing crop was apparent in May 1982 as compared with the adjacent control area. There was no negative impact on percent cover of Porphyra (mostly P. perforata) within 1 year after hand harvest of seven, approximately 1-m2 plots, as compared with respective controls. Annual fluctuation in cover, biomass, and relative mix of Porphyra species was large. Porphyra cover in a small plot harvested in early June 1981 increased to 86% of the June value by mid-July 1981, indicating substantial growth of the remaining thallus fragments and small, whole plants within one season. It was concluded that sustained yield of Porphyra beds can be assured if harvest is restricted to gathering by hand.

Nondestructive Estimation of Standing Crop and Fuel Moisture Content in Tallgrass Prairie

2018 ◽  
Vol 71 (3) ◽  
pp. 356-362 ◽  
Author(s):  
Sonisa Sharma ◽  
Tyson E. Ochsner ◽  
Dirac Twidwell ◽  
J.D. Carlson ◽  
Erik S. Krueger ◽  
...  
Keyword(s):  
Moisture Content ◽  
Tallgrass Prairie ◽  
Standing Crop ◽  
Fuel Moisture ◽  
Fuel Moisture Content ◽  
Nondestructive Estimation

EFFECT OF HARVEST DATE AND SWATHING ON MOISTURE CONTENT AND CHLOROPHYLL CONTENT OF CANOLA SEED

1989 ◽  
Vol 69 (3) ◽  
pp. 925-928 ◽  
Author(s):  
S. CENKOWSKI ◽  
S. SOKHANSANJ ◽  
F. W. SOSULSKI
Keyword(s):  
Moisture Content ◽  
Standing Crop ◽  
Brassica Campestris ◽  
Seed Color ◽  
Canola Seed ◽  
Seed Moisture Content ◽  
Chlorophyll Contents ◽  
Green Seed ◽  
Seed Moisture ◽  
Canola Quality

A standing crop of Tobin canola-quality rapeseed (Brassica campestris L.) was sampled and swathed at 4-d intervals between 52 and 10% (wb) seed moisture content. Percentages of distinctly green seeds and chlorophyll contents of seeds were assessed. Swathing hastened loss of green seed color by about 2 d as compared to seeds on standing plants.Key words: Canola, harvest stage, green seed, chlorophyll

scholarly journals Monitoring recovery of overgrazed lichen communities on Hagemeister Island, southwestern Alaska

Rangifer ◽  
2021 ◽  
Vol 41 (1) ◽  
pp. 1-12
Author(s):  
Patrick Walsh ◽  
Trevor Goward
Keyword(s):  
Community Composition ◽  
Recovery Rate ◽  
Rangifer Tarandus ◽  
Growth Curves ◽  
Full Recovery ◽  
Lichen Community ◽  
Forage Species ◽  
Northern Regions ◽  
Southwestern Alaska

Understanding the recovery rate of overgrazed lichen communities has value to mangers of lands in northern regions.  We describe lichen community composition and present recovery rate measurements for a 12-year period following overgrazing by reindeer (Rangifer tarandus) on Hagemeister Island, Alaska.  Reindeer were removed from the island in 1993 following overgrazing and average total lichen biomass increased from 504.2 kg/ha (SD 205.4) in 2003 to 795.3 (SD 489.6) in 2015.  We estimate time to recovery with three competing growth curves which estimate grazeable biomass may be reached in 34-41 years.  However, estimates of full recovery to climax biomass varied among the models, ranging from 71 to 400 years.   In 2015, lichen communities were composed of various mixtures of at least 78 lichen taxa, and were dominated by Cladina stygia and other important reindeer forage species.   While reindeer overgrazing diminished forage quantity, it did not extirpate preferred forage taxa.  

scholarly journals Effect of Substrate Characteristics on the Growth and Sporulation of Two Biocontrol Microorganisms during Solid State Cultivation

Fermentation ◽  
2020 ◽  
Vol 6 (3) ◽  
pp. 69
Author(s):  
Ga Young Lee ◽  
Wenqi Li ◽  
Ulalo M. Chirwa ◽  
Jian Shi
Keyword(s):  
Solid State ◽  
Moisture Content ◽  
Profile Analysis ◽  
Initial Moisture Content ◽  
Streptomyces Griseus ◽  
Strain Curve ◽  
Spore Production ◽  
Biocontrol Agents ◽  
Plate Count ◽  
Texture Profile

Biocontrol agents are a group of naturally occurring organisms capable of interrupting the lifespan and suppressing the propagation of disease organisms. The use of biocontrol agents offers an environment-friendly and sustainable solution to the synthetic agrochemicals. In this study, we investigated parboiled rice and millets as substrates for spore production of two model biocontrol microorganisms (Bacillus pumilus and Streptomyces griseus) under solid state cultivation (SSC) conditions. The effects of cultivation parameters such as initial moisture content, water activity, and cultivation time on microbial growth and spore production were studied. Furthermore, texture profile analysis was performed to test the stress and strain curve and the hardness and stickiness of the substrates. The greatest spore production occurred at 50% moisture content with millets as a substrate, yielding a count of 1.34 × 108 spores/g-wet-substrate enumerated with plate count analysis and 1.70 × 108 events/g-wet-substrate using flow cytometry analysis. Substrate texture profile was highly correlative to the initial moisture content and substrate type and all proved to be essential process variables in controlling the bacterial growth and sporulation during SSC processes.

Effect of sewage effluent on soil fauna in a Pinus-radiata plantation

Soil Research ◽  
1995 ◽  
Vol 33 (3) ◽  
pp. 555 ◽  
Author(s):  
GW Yeates
Keyword(s):  
Moisture Content ◽  
Pinus Radiata ◽  
Soil Fauna ◽  
Late Summer ◽  
Control Area ◽  
Sewage Effluent ◽  
Soil Processes ◽  
Dune Sands ◽  
Treated Area ◽  
Spray Irrigation

Water and nutrients in effluent applied to land may influence soil processes. This study uses late summer and autumn samples to assess changes in litter and soil fauna under a 17-year-old Pinus radiata plantation on dune sands of the Waitarere-Hokio association after 7 years of spray irrigation of sewage effluent. Populations estimated included 12 groups of litter arthoropods, earthworms, enchytraeids, tardigrades, rotifers and nematodes. Three groups of litter arthropods (adult diptera, spiders and aphids) were significantly less abundant in the effluent-treated area than in the unirrigated control. Increased moisture content was apparently responsible for greatly increased populations of earthworms and nematodes in the effluent-treated area. Bacterial-feeding and predatory nematodes showed marked increases, while fungal-feeding nematodes declined significantly. The nematode maturity index (MI) was lower in all treated plots. After effluent had been withheld for 52 days, there were significant increases in isopods and Collembola. Rotifers were most abundant in the control area. It appears that effluent enhanced physical breakdown of the P. radiata litter. Movement of the decayed fragments into the upper layers of sand may have produced conditions unfavourable for enchytraeids and rotifers.

Litterfall, growth, and turnover of arboreal lichens after partial cutting in an Engelmann spruce – subalpine fir forest in north-central British Columbia

2003 ◽  
Vol 33 (12) ◽  
pp. 2306-2320 ◽  
Author(s):  
Susan K Stevenson ◽  
Darwyn S Coxson
Keyword(s):  
British Columbia ◽  
Growth Rates ◽  
Standing Crop ◽  
Control Area ◽  
Abies Lasiocarpa ◽  
Partial Cutting ◽  
North Central ◽  
Relative Growth Rates ◽  
Single Tree ◽  
Single Tree Selection

Dynamics of canopy lichens were investigated for 2 years after group and single-tree selection harvesting in a Picea engelmannii Parry ex Engelm. – Abies lasiocarpa (Hook.) Nutt. forest in north-central British Columbia. Litter fall was collected in 1-m2 traps set on the forest floor and estimates of Alectoria sarmentosa (Ach.) Ach. and Bryoria spp. litterfall adjusted for decomposition in the snowpack. Growth rates of A. sarmentosa and Bryoria fuscescens (Gyeln.) Brodo & D. Hawksworth were measured by repeatedly weighing samples maintained in mesh enclosures in the canopy. Standing crop of canopy lichens was measured in concurrent studies. There appeared to be a small postharvest pulse of litterfall in the single-tree selection area, but it was largely masked by natural variation. Ninety percent of the lichen litterfall was deposited within 10 m of the nearest tree. Annual relative growth rates of A. sarmentosa and B. fuscescens ranged from 2.7% to 10.4% and from 2.4% to 9.1%, respectively. Growth rates of both species were as high in the single-tree selection area as in the unlogged control area but were reduced along the edges of group selection openings. Growth and turnover (annual litterfall as a percentage of standing crop) of Alectoria were approximately in balance, but growth of Bryoria exceeded turnover. In situ decomposition of Bryoria may account for the difference.

Prevalence of Toxocara canis ova in public playgrounds in the Dublin area of Ireland

1994 ◽  
Vol 68 (3) ◽  
pp. 237-241 ◽  
Author(s):  
P. O'Lorcain
Keyword(s):  
Moisture Content ◽  
Recovery Rate ◽  
Toxocara Canis ◽  
Toxocara Cati ◽  
Term Survival ◽  
Significant Difference ◽  
Egg Density ◽  
Flotation Method ◽  
Toxascaris Leonina

AbstractA total of nine playground sites in Dublin city and county were surveyed from which 228 samples were removed. Of these samples, 15% were positive for Toxocara canis ova and a mean egg density of 1.4 ova/100 g was calculated. Two types of playground sites were identified and that the level of toxocaral contamination was found to be greater in ‘neighbourhood playgrounds’ than in ‘adventure playgrounds’. There was no significant difference in the number of positive samples taken from sites both inside and outside these playgrounds. No evidence of Toxocara cati ova was found. Only one sample was positive for Toxascaris leonina ova. Over 50% of the T. canis ova identified were infective. The findings in this study suggest that the sample's moisture content contributes to the long term survival of infective Toxocara ova in the environment. A recovery rate of 69.8% was achieved with a modified version of the flotation method.

Effect of preharvest applications of glyphosate on the drying, yield and quality of wheat

1994 ◽  
Vol 74 (2) ◽  
pp. 221-230 ◽  
Author(s):  
A. L. Darwent ◽  
K. J. Kirkland ◽  
L. Townley-Smith ◽  
K. N. Harker ◽  
A. J. Cessna ◽  
...  
Keyword(s):  
Triticum Aestivum ◽  
Moisture Content ◽  
Standing Crop ◽  
Seed Quality ◽  
Seed Moisture Content ◽  
Baking Quality ◽  
Moisture Contents ◽  
Seed Moisture ◽  
Direct Cutting

In experiments conducted from 1988 to 1990 at four locations in the Parkland zone of western Canada, the drydown of seed and foliage, seed yield, seed quality and baking quality of wheat (Triticum aestivum L.) following preharvest applications of glyphosate were compared with those following windrowing prior to harvest or direct cutting of the standing crop. Glyphosate was applied in late July to early September at rates of 0.45, 0.9 and 1.7 kg acid equivalent ha−1 to wheat with seed moisture contents ranging from 80 to 11%. When compared with a standing crop, all glyphosate treatments applied at seed moisture contents above 25% slightly enhanced the drydown of wheat seed and foliage. Treatments applied at seed moisture contents below 25% had no effect on either seed or foliage drydown. Seed yields were generally greater from plots to which glyphosate was applied than from windrowed control plots, although in one of five experiments the reverse trend occurred. Increasing the rate from 0.45 to 1.7 kg ha−1 had no effect on yield. Windrowing or applying glyphosate to wheat with a seed moisture content of 61% or more reduced yields more than windrowing or applying glyphosate at seed moisture contents below this level. In experiments where the wheat in both control and sprayed plots was direct cut at maturity, average yields decreased as the rate of glyphosate increased from 0 to 1.7 kg ha−1. However, applications at seed moisture of 40% or less, caused little or no yield loss. There was little or no difference in 1000-seed weight, sample density, seed germination and protein content from plots sprayed with glyphosate at seed moisture contents below 40% than from control plots windrowed at the same moisture content or direct cut at maturity. Baking quality was not affected by any of the glyphosate treatments in experiments where the wheat was harvested by direct cutting. Key words: Glyphosate, wheat, desiccation, wheat quality, Triticum aestivum

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