RÚCULA HIDROPÔNICA SOB DIFERENTES DENSIDADES E CONCENTRAÇÕES DE SOLUÇÃO NO PERÍODO DE OUTONO E INVERNO / HYDROPONIC ROCKET UNDER DIFFERENT DENSITIES AND SOLUTION CONCENTRATIONS IN THE AUTUMN AND WINTER PERIOD

A number of water utilities have been experiencing operational difficulties during specific times of the year, associated with elevated levels of organics due to heavy rainfall or snow melt. Water samples were collected from Albert treatment works (Halifax, UK) and the natural organic matter (NOM) was characterised using XAD resin adsorption techniques. The addition of a cationic polyelectrolyte was employed to determine the charge density of the fractions. Results show that NOM fraction make-up changes throughout the year, with the fulvic acid fraction (FAF) showing the greatest increase during the autumn and winter period. The charge density of the FAF fraction also increases. The coagulation conditions for traditional coagulants, such as iron, are more affected by increased levels of organics than the novel coagulant also investigated, and the zeta potential range for optimum removal is narrower. Therefore, the conditions required for zero charge during coagulation varies with both raw water source and the coagulant type.

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Occurrence of Enchytraeid worms and some properties of their casts in an Australian soil under cropping

Soil Research ◽

10.1071/sr9950651 ◽

1995 ◽

Vol 33 (4) ◽

pp. 651 ◽

Cited By ~ 12

Author(s):

KY Chan ◽

DP Heenan

Keyword(s):

Size Range ◽

Chemical Properties ◽

Bulk Soil ◽

Winter Period ◽

Wagga Wagga ◽

Red Earth ◽

Autumn And Winter ◽

Physical And Chemical ◽

Australian Soil ◽

And Chemical Properties

The population density of enchytraeid worms (Oligochaeta) was monitored on a red earth (Oxic Paleustalf) under cropping in Wagga Wagga, N.S.W. Physical and chemical properties of their casts were compared with those of the bulk soil and soil sampled adjacent to the permanent fenceline. In the autumn and winter period, the worm population was active close to the surface and the highest population (2037 per m(2)) was detected in the direct drilled/stubble burnt treatment. However, this was considerably lower than those reported elsewhere in temperate regions. Worm casts were composite in nature, predominately of 210-500 �m in diameter which were comprised of smaller spherical subunits (50-100 �m). The casts were found to be significantly more water stable and higher in total nitrogen than aggregates of the same size range separated from the bulk soil. Porosity of the casts was dominated by spaces between the subunits which were composed of very densely packed clay/silt size particles. Evidence from SEM (scanning electron microscope) suggests that the high stability was due to the presence of cements.

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Can Green Plants Mitigate Ammonia Concentration in Piglet Barns?

Atmosphere ◽

10.3390/atmos12091150 ◽

2021 ◽

Vol 12 (9) ◽

pp. 1150

Author(s):

Simona Menardo ◽

Werner Berg ◽

Heiner Grüneberg ◽

Martina Jakob

Keyword(s):

Animal Welfare ◽

Ornamental Plants ◽

Ammonia Concentration ◽

Winter Period ◽

Green Plants ◽

Co2 Balance ◽

Gas Measurements ◽

Ventilation Rates ◽

Autumn And Winter ◽

Control Compartment

For animal welfare and for farmers’ health, the concentration of ammonia (NH3) in animal houses should be as low as possible. Plants can remove various atmospheric contaminants through the leaf stomata. This study examined the effect of ornamental plants installed inside a piglet barn on the NH3 concentration in the air. Gas measurements of the air in the ‘greened’ compartment (P) and a control compartment (CTR) took place over two measuring periods (summer–autumn and winter). Differences between the NH3 emissions were calculated based on the ventilation rates according to the CO2 balance. Fairly low mean NH3 concentrations between 2 and 4 ppm were measured. The NH3 emissions were about 20% lower (p < 0.01) in P than in CTR, in summer–autumn and in winter period.

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CONTENT OF THE DISSOLVED OXYGEN IN THE SEA OF AZOV DURING THE AUTUMN AND WINTER PERIOD IN 2015

Science in the South of Russia ◽

10.23885/2500-0640-2017-13-1-126-130 ◽

2017 ◽

Vol 13 (1) ◽

pp. 126-130

Author(s):

V.S. Gerasyuk ◽

Keyword(s):

Dissolved Oxygen ◽

Winter Period ◽

Sea Of Azov ◽

The Sea Of Azov ◽

Autumn And Winter

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Positive feedback of elevated CO<sub>2</sub> on soil respiration in late autumn and winter

Biogeosciences Discussions ◽

10.5194/bgd-11-8749-2014 ◽

2014 ◽

Vol 11 (6) ◽

pp. 8749-8787 ◽

Cited By ~ 2

Author(s):

L. Keidel ◽

C. Kammann ◽

L. Grünhage ◽

G. Moser ◽

C. Müller

Keyword(s):

Soil Respiration ◽

Elevated Co2 ◽

Management Practices ◽

Co2 Enrichment ◽

Terrestrial Ecosystems ◽

Winter Period ◽

Elevated Atmospheric Co2 ◽

Late Autumn ◽

Below Ground ◽

Autumn And Winter

Abstract. Soil respiration of terrestrial ecosystems, a major component in the global carbon cycle is affected by elevated atmospheric CO2 concentrations. However, seasonal differences of feedback effects of elevated CO2 have rarely been studied. At the Giessen Free-Air CO2 Enrichment (GiFACE) site, the effects of +20% above ambient CO2 concentration (corresponds to conditions reached 2035–2045) have been investigated since 1998 in a temperate grassland ecosystem. We defined five distinct annual periods, with respect to management practices and phenological cycles. For a period of three years (2008–2010), weekly measurements of soil respiration were carried out with a survey chamber on vegetation-free subplots. The results revealed a pronounced and repeated increase of soil respiration during late autumn and winter dormancy. Increased CO2 losses during the autumn period (September–October) were 15.7% higher and during the winter period (November–March) were 17.4% higher compared to respiration from control plots. However, during spring time and summer, which are characterized by strong above- and below-ground plant growth, no significant change in soil respiration was observed at the FACE site under elevated CO2. This suggests (i) that soil respiration measurements, carried out only during the vegetative growth period under elevated CO2 may underestimate the true soil-respiratory CO2 loss (i.e. overestimate the C sequestered) and (ii) that additional C assimilated by plants during the growing period and transferred below-ground will quickly be lost via enhanced heterotrophic respiration outside the main vegetation period.

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Grooming of horses in autumn and winter period

Theoretical and Applied Veterinary Medicine ◽

10.32819/2019.74036 ◽

2019 ◽

Vol 7 (4) ◽

pp. 205-209

Author(s):

K. D. Dynnikova ◽

S. G. Pishchan ◽

O. V. Lesnovska ◽

L. V. Karlova

Keyword(s):

Winter Period ◽

Autumn And Winter

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Studies on the biology of limpets IV. The breeding of patella depress a pennant on the north Cornish coast

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315400016210 ◽

1961 ◽

Vol 41 (3) ◽

pp. 653-662 ◽

Cited By ~ 31

Author(s):

J. H. Orton ◽

A. J. Southward

Keyword(s):

Small Proportion ◽

Gonad Development ◽

Early Spring ◽

The Other ◽

Winter Period ◽

The North ◽

Air Temperatures ◽

The Common ◽

Post Spawning ◽

Autumn And Winter

SUMMARYThe breeding of Patella depressa was studied at Trevone, North Cornwall, for 4 years. Gonads were examined and assessed by methods described in a previous report on P. vulgata.In contrast to the common Limpet, P. depressa is a summer breeder in Cornwall. Gonad development begins in the spring and is complete by June or July. Spawning coincides with maximum air temperatures in July, August or early September. The autumn and winter period is passed with gonads in recognizable post-spawning and spent stages, and only a small proportion of completely resting neuter gonads is found in the early spring.Mass spawning takes place, and gametes are voided rapidly. No definite spawning stimulus can be shown, but, as with P. vulgata, there may be some relation between onset of spawning and the occurrence of wave action on the shore.The differences in breeding behaviour of P. depressa and P. vulgata reinforce the other differences between them and throw some doubt on the concept of super-species in Patella.

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Studies in Crop Variation VII. The Influence of Rainfall on the Yield of Barley at Rothamsted

The Journal of Agricultural Science ◽

10.1017/s0021859600006948 ◽

1930 ◽

Vol 20 (3) ◽

pp. 417-439 ◽

Cited By ~ 7

Author(s):

J. Wishart ◽

Winifred A. Mackenzie

Keyword(s):

Farmyard Manure ◽

Winter Period ◽

Period 2 ◽

Short Period ◽

Final Yield ◽

Cool Summer ◽

Autumn And Winter ◽

Main Effects ◽

Alkali Salts ◽

Winter Rain

VI. SummaryThe conclusions of an earlier study of the yield of dressed grain from Hoos Field over the period 1852–1921 are recalled, and the method of conducting an examination of the influence of rainfall on the yield is described. The method yields a series of curves showing at any given period of the year the benefit or loss to the final yield in bushels per acre due to an additional inch of rain over the average at that period. Thirteen plots are considered, and the curves are found to fall roughly into groups corresponding to the system of manuring adopted. The main effects noted are these: (1) Excess of rain is beneficial to the barley crop for a short period in summer, and, in the case of certain plots, over the autumn and winter period. This is in contrast to the corresponding result for wheat on Broadbalk, where excess of rain was found to be beneficial only on a few plots and over a very limited period. (2) Rainfall over the six months when the barley is not in the ground is just as important as rainfall in spring and summer, and the time at which the rain falls in winter is important. Excess of rain in autumn benefits plots 1–A, 3–A and 7–2, and in winter continues to benefit 1–A and 3–A. (3) The curves for 2–O and 2–A are essentially different in character from those of the other plots, and point to the important effect of excess of winter rain in reducing the yield of the plots having phosphate but no alkali salts (i.e. no potash, soda, magnesia). (4) Excess of rain at time of sowing is harmful in all cases. (5) The curves of the “O” series (without nitrogen) are much flatter than those of the “A” series, which have a nitrogenous dressing in addition. (6) The indication of summer benefit is not inconsistent with the conclusions of Hooker that a cool summer is desirable for barley. (7) The farmyard manure plot 7–2 bears certain resemblances to the curve for the corresponding plot 2 b on Broadbalk.

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Environmental factors which influence the hibernation behaviour of the Natal long- fingered bat ( Miniopterus natalensis ) in the Bakwena Cave, Gauteng

Suid-Afrikaanse Tydskrif vir Natuurwetenskap en Tegnologie ◽

10.4102/satnt.v31i1.346 ◽

2012 ◽

Vol 31 (1) ◽

Author(s):

M. I. Moir ◽

J. F. Durand

Keyword(s):

Environmental Factors ◽

Winter Period ◽

Average Mass ◽

Autumn And Winter ◽

Forearm Length

One of the maingoals of this study was to calculate the average mass and forearm length of a colony of Miniopterus natalensis(Natal long-fingered bat) over the autumn and winter months in order todetermine whether there was a decrease in average mass over the winter period.

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