• Animal cells and systems
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• v.7 no.4
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• pp.289-294
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• 2003

To quantify nutrient loading from emergent macrophytes through leaching in the littoral zones of Paldang Reservoir, we conducted incubation experiments using leaf litter of the emergent macrophyte, Zizaniz latifolia. To separate the leaching process from microbial decay, we used $HgCl_2$ to suppress microbial activity during the experiment. We measured electric conductivity, absorbance at 280nm, total nitrogen and dissolved inorganic nitrogen, total phosphorus and soluble reactive phosphorus, Na, K, Mg and Ca amounts in leaf litter and in water. In addition, we examined the effects of water temperature and ion concentrations of ambient water on the leaching process. A total of 6% of the initial ash-free dry mass of leaf litter was lost due to leaching during incubation (four days). Electric conductivity and A280 continued to increase and saturate during the incubation. To compare reaching rates of different nutrients, we fitted leaching dynamics with a hyperbolic saturation function [Y=AㆍX/(B+X)]. From these fittings, we found that ratios of leaching amounts to nutrient concentration in the litter were in the order of K > Na > Mg > P > Ca > N. Leaching from leaf litter of Z. latifolia was dependent on water temperature while it was not related with ion concentrations in the ambient water. Our results suggest that the leaching process of nutrients, especially phosphorus, from aquatic macrophytes provides considerable contribution to the eutrophication of the Paldang Reservoir ecosystem.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.4
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• pp.555-557
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• 2003

A total of 168 seven days-old Arbor Acres chicks were reared in late-autumn on 4 types of litters; sawdust, rice husk, sugarcane bagasse or wheat straw up to 49 days of age to compare the growth performance, evaluate the manureal value and Coccidial oocyst population in used litter. Sadust, rice husk, sugarcane bagasse and wheat straw did not differ statistically for live weight, feed consumption, feed conversion ratio and survivability (p>0.05). However, live weight and survivability tended to increase on sawdust. The highest moisture content of used litter was found in sugarcane bagasse followed by sawdust, rice husk and wheat straw (p<0.05). Rice husk contained the highest amount of of nitrogen, phosphurus and potassium followed by sawdust, sugarcane bagasse and wheat straw (p<0.01). Oocyst content of all treatment groups increased suddenly up to 5 weeks of age and thereafter suddenly declined up to 7 weeks of age. Litter materials did not differ at 35 and 42 days of age for oocyst content, but significantly differed at 49 days of age (p<0.01). So, the above findings reveal that sawdust may be suitable litter followed by rice husk, sugarcane bagasse and wheat straw in late-autumn in Bangladesh in respect of broiler growth performance.

• The Korean Journal of Ecology
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• v.20 no.5
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• pp.329-337
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• 1997

Study of population density and biomass of soil microarthropods in soil, herbaceous leaf litter and wood leaf litter was conducted at 4 sites with different flora in Mt. Jumbong, a nature reserve area, in Korea from Aug. 1994 to May 1996. Total 47, 849 individuals of soil microarthropods in soil were collected and identified into 6 different classes, and 16 orders. The composition, densities, and dominant group of soil microarthropods were different among 4 sampling sites. Collembola was the most abundant group with 50.7% at South-facing slope and 50.6% at the North-facing slope. But Acari was the most abundant group with 49.8% at Altitude 900m site and 47.7% at Altitude 1100m site. Two group ranged 87-95% of total individuals. A/C ratio was less than 1.0 at 4 sampling sites during the all sampling seasons. As a result of biomass evaluation, rato of Acari was decreased but ratio of Diplopoda, coleoptera, Araneae, Diptera and Chilopoda was increased. About 70% of total orders and densities were found in less than 5cm soil depth. The composition, densities, and dominant group of soil microarthropods were different among soil, herbaceous litter and wood litter. Collembola was the most abundant group in herbaceous and wood litter. A/C ratio was less than 1.0 in litter during the sampling seasons. As a result of biomass evaluation in litter, ration of Araneae and Collembola was very high, but ratio of Acari was low.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.3
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• pp.300-306
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• 1998

An experiment was conducted to investigate correlations of litter size and average serum progesterone concentrations during pregnancy with mammary gland growth and development at parturition. Twenty ewes (5, 9, 4, and 2 ewes carrying 0, 1, 2, and 3 lambs, respectively) were used to measure weekly serum progesterone concentration during pregnancy. At parturition, the experimental ewes were slaughtered for determination of mammary gland growth and development at parturition (mammary dry fat-free tissue [DFFT], DNA, RNA, collagen, protein, and glycogen). Correlation of mammary DFFT with litter size and averages serum progesterone concentrations were 0.75 and 0.72, respectively. Litter size or maternal serum progesterone concentrations did not correlate with the mammary DNA concentration. However, litter size or maternal serum progesterone concentrations positively correlated (p < 0.01) with the mammary RNA and protein concentrations, but negatively correlated with the mammary collagen (p < 0.01) and. glycogen (p < 0.05) concentrations. Litter size or maternal serum progesterone positively correlated (p < 0.01) with the total mammary DNA, RNA, collagen, protein and glycogen contents. These results implied that the increased concentrations of progesterone with the increased litter size during pregnancy improved mammary gland growth and development at parturition.

• The Korean Journal of Ecology
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• v.19 no.6
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• pp.563-573
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• 1996

Macroinvertebrate contribution to the leaf litter breakdown of Carpinus cordata was estimated at headwater streams at Mt. Jumbong (38°03'N, 128°25'E) during spring and winter spring by using two types of litter bag. Coarse-mesh bags with 10 g of leaf letter were placed in a 1st-order stream in April (the spring experiment) and December 1995 (the winter-spring experiment). Fine-mesh bags with 5 g of leaf letter were placed in a nearby 3ed-order steam. The breakdown of Carpinus in coarse-mesh bags was rapid, and, in terms of season, leaf litter processed rapidly during spring. daily mass loss rates of leaf litter (-k±1 SE) were highest for coarse-mesh bags in the spring experiment (-0.0429±0.0048), followed by coarse-mesh bags in the winter-spring (-0.0146±0.0014), fine-mesh bags in the spring (-0.0078±0.0004), fine-mesh bags in the winter-spring experiment (-0.0054±0.0005). Macroinvertebrate contribution to the litter breakdown was estimated by the difference of % leaf letter remaining between coarse -mesh bage and fine-mesh bags. Although shredders were more abundant during the winter-spring, their contribution was greater during the spring (50%) than the winter-spring (22∼33%). This result appeared to be due to the change in the chemical composition of leaf letter during processing, and to the seasonal growth patterns of major shredder taxa.

• Journal of Environmental Science International
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• v.26 no.10
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• pp.1181-1184
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• 2017

This study examined the effects of chemical blends (a combination of alum and aluminum chloride) on pH, N, and pathogens in duck litter during a six-week experiment. In total, 240 Pekin ducks (160 males and 80 females) were individually distributed into 16 pens, in a randomized experimental design consisting of four treatments and four replicate pens per treatment. Our treatments included a control, T1 (75 g alum + 75 g aluminum chloride/kg duck litter), T2 (100 g alum + 100 g aluminum chloride/kg duck litter), and T3 (150 g alum + 150 g aluminum chloride/kg duck litter). There was no difference among treatments in pH and Total N (TN) at weeks 2, 4, and 6 and weeks 1, 4, 5, and 6, respectively. However, there were significant differences in both pH and TN among treatments at weeks 1, 3, and 5 and weeks 2 and 3, respectively. Regarding pathogens, we found small differences in all treatments in Escherichia coli populations from weeks 1 to 5 and in Salmonella enterica populations from weeks 1 to 3. In conclusion, the addition of chemical blends to duck litter increased TN, which resulted in a lower litter pH, but did not significantly affect pathogen populations.

• Journal of Climate Change Research
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• v.8 no.4
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• pp.385-391
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• 2017

This study was conducted to estimate litter carbon stock change from the National Forest Inventory (NFI) data for national greenhouse gas inventory report. Litter carbon stocks were calculated from the NFI dataset in NFI5 (2008) and NFI6 (2013) in Gangwon province. Total carbon stock change of litter was $0.68{\pm}0.71\;t\;C/ha$ from NFI5 (2008) to NFI6 (2013), however, there was no significant difference between the both dataset at 2008 and 2013 year. Litter carbon stock of coniferous stands was higher than deciduous stands in NFI5 (2008) and NFI6 (2013) (P<0.05). This study was limited to pilot study, so we will assess litter carbon stock using more complete data from NFI systems. It can be used as data sources for national greenhouse gas inventory report on forest sector.

• Journal of Environmental Science International
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• v.28 no.2
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• pp.287-290
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• 2019

This study investigates the changes in ammonia fluxes, pH and total nitrogen of liquid ferrous sulfate-treated litter over 5 weeks. A total of 200 broiler chicks (Arbor Acres, 1 d old) was separated into two treatment groups (0 g and 100 g liquid ferrous sulfate/kg litter) with four replications of 25 birds in each group. Liquid ferrous sulfate was sprayed on the litter by using a small sprayer. There was no difference (p>0.05) in the ammonia fluxes observed between the control and liquid ferrous sulfate treatment groups at 0, 1, and 5 weeks, except for 2, 3 and 4 weeks. At 5 weeks, the litter pH and total nitrogen content did not show any difference (p>0.05) between the control and liquid ferrous sulfate treatment groups. In conclusion, the use of liquid ferrous sulfate is not a suitable for use in poultry litter to reduce ammonia and pH or improve the total nitrogen content.

• Applied Chemistry for Engineering
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• v.33 no.4
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• pp.408-418
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• 2022

Marine accidents involving the entanglement of marine litter have continued to increase, with over 300 to 400 cases per year according to the statistical agency. Entanglement of marine litter may also lead to large-scale marine accidents which cause capsizing and sinking, thereby further causing detrimental casualties and material damages, and thus exceptional attention and care are required. In this study, Incheon, Busan, and Geoje and Tongyeong were found to be the high-frequency locations for accidents, which were selected by considering the ArcGIS analysis about the marine accidents of entanglement of marine litter and the occurrence frequency by the standard. The characteristics of the multiple accident areas involving entanglement of marine litter were the coastal cities where fishing facilities or marine leisure related conditions were activated, with the port which handles much of the traffic of outbound and inbound vessels located nearby. Marine plastic pollution impacts not only the marine ecosystem and food chain, but also the hull and engine of ships, and may further pose threats to the safety of vessels and crews. It is necessary to find a common link between the relevant areas and to strive to remove the root causes of marine accidents by reducing marine litter.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.2
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• pp.267-274
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• 2017

Objective: The objective of this study was to investigate the effect of 20-day litter weight on behavior and heart rate variability (HRV) of piglets under stress. Methods: Forty four original litters were categorized as high litter weight (HW) litters (n = 22) and low litter weight (LW) litters (n = 22) by 20-day litter weight. From each original HW litter, three males and three females were randomly selected after weaning and the 12 piglets from two original litters with similar age of days were regrouped into one new high litter weight (NHW) litter (11 NHW litters in total). The original LW litters were treated with a same program, so that there were 11 new low litter weight (NLW) litters as well. The latencies to first fighting, fighting frequencies and duration within three hours were recorded after regrouping and the lesions on body surface within 48 hours were scored. Besides, HR (heart rate, bpm, beats per minute) and activity count (ACT), time domain indexes and frequency domain indexes of the piglets were measured in an isolation trial to analyze the discrepancy in coping with stress between the original HW and LW litters. Results: The results exhibited that piglets from the HW litters launched fighting sooner and got statistically higher skin lesion score than those from the LW litters (p = 0.03 and 0.02, respectively). Regarding the HRV detection, compared with the HW litters, the LW litters exhibited a lower mean HR (p<0.05). In the isolation test, a highly significant higher ACT value was observed between the HW litters, compared to the LW litters (p<0.01). Significant differences were observed in standard deviation of R-R intervals, standard deviation of all normal to normal intervals, and most frequency-domain indicators: very low-frequency, low-frequency, and high frequency between the HW and LW litters as well. The difference in LF:HF was not significant (p = 0.779). Conclusion: This study suggests that compared with litters of low 20-day litter weights, litters with higher 20-day litter weight take more positive strategies to cope with stress and have stronger HRV regulation capacity; HW litters demonstrate better anti-stress and adaptation capacity in the case of regrouping and isolation.