• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.1-7
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• 2007

New Zealand is a hydrologically diverse and active country. This paper presents an overview of the major hydrological issues and problems facing New Zealand and provides examples of some the research being undertaken to solve the problems. Fundamental to any environmental decision making is the provision of good quality hydrometric data. Reduced funding for the national hydrometric network has meant a reduction in the number of monitoring sites, the decision on how to redesign the network was made using information on geographic coverage and importance of each site. New Zealand faces a major problem in understanding the impacts of rapid land use change on water quantity and quality. On top of the land use change is overlain the issue of agricultural intensification. The transfer of knowledge about impacts of change at the small watershed scale to much larger, more complex watersheds is one that is attracting considerable research attention. There is a large amount of research currently being undertaken to understand the processes of water and nutrient movement through the vadose zone into groundwater and therefore understanding the time taken for leached nutrients to reach receiving water bodies. The largest water management issue of the past 5 years has been based around fair and equitable water allocation when there is increasing demand for irrigation water. Apart from policy research into market trading for water there has been research into water storage and transfer options and improving irrigation efficiency. The final water management issue discussed concerns the impacts of hydrological extremes (floods and droughts). This is of particular concern with predictions of climate change for New Zealand suggesting increased hydrological extremes. Research work has concentrated on producing predictive models. These have been both detailed inundation models using high quality LIDAR data and also flood models for the whole country based on a newly interpolated grid network of rainfall.

• Proceedings of the Korean Environmental Sciences Society Conference
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• 2019.10a
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• pp.134-134
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• 2019

Utilization of organic waste as a renewable energy source is promising for sustainability and mitigation of climate change. Pyrolysis converts organic waste to gas, oil, and biochar by incomplete biomass combustion. Biochar is widely used as a soil conditioner and adsorbent. Biochar adsorbs/desorbs metals and ions depending on the soil environment and condition to act as a nutrient buffer in soils. Biochar is also regarded as a carbon storage by fixation of organic carbon. Phosphorus (P) and nitrogen (N) are strictly controlled in many wastewater treatment plants because it causes eutrophication in water bodies. P and N is removed by biological and chemical methods in wastewater treatment plants and transferred to sludge for disposal. On the other hand, P is an irreplaceable essential element for all living organisms and its resource (phosphate rock) is estimated about 100 years of economical mining. Therefore, P and N recovery from waste and wastewater is a critical issue for sustainable human society. For the purpose, intensive researches have been carried out to remove and recover P and N from waste and wastewater. Previous studies have shown that biochars can adsorb and desorbed phosphates implying that biochars could be a complementary fertilizer. However, most of the conventional biochar have limited capacity to adsorb phosphates and nitrate. Recent studies have focused on biochar impregnated with metal salts to improve phosphates and nitrate adsorption by synthesizing biochars with novel structures and surface properties. Metal salts and metal oxides have been used for the surface modification of biochars. If P removal is the only concern, P adsorption kinetics and capacity are the only important factors. If both of P and N removal and the application of recovery are concerned, however, P and N desorption characteristics and bioavailability are also critical factors to be considered. Most of the researches on impregnated biochars have focused on P removal efficiency and kinetics. In this study, coffee waste is thermally treated to produce biochar and it was impregnated with Mg/Al to enhance phosphates and nitrate adsorption/desorption and P bioavailability to increase its value as a fertilizer. Kinetics of phosphates and nitrate adsorption/desorption and bioavailability analysis were carried out to estimate its potential as a P and N removal adsorbent in wasewater and a fertilizer in soil.

• The Journal of Information Systems
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• v.32 no.4
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• pp.137-147
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• 2023

Purpose The domestic aquaculture industry in South Korea utilizes both formulated feeds and live feeds for the cultivation of fish. While nutrient-rich live feeds, particularly using fry, have been preferred since the past, formulated feeds are gaining attention due to issues related to overfishing and environmental concerns. Formulated feeds are advantageous for storage and supply but require a sustained feeding regimen due to the comparatively slower growth rate compared to live feeds. As the aging population in rural areas leads to a shortage of labor, automated feeding systems are increasingly being adopted in aquaculture facilities. To enhance the efficiency of such systems, it is crucial to quantitatively analyze the behavioral changes in fish based on the presence or absence of feed. Design/methodology/approach In the study, RGB cameras and infrared cameras were used to analyze fish activity according to feeding, and an outline extraction algorithm was applied to analyze the differences resulting from this. Findings Unlike RGB cameras, infrared cameras are more suitable for analyzing underwater fish activity as they convert objects' thermal energy into images. It was observed that Canny, Sobel, and Prewitt filters showed the most distinct identification of fish activity.

• Journal of Nutrition and Health
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• v.57 no.2
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• pp.185-195
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• 2024

Purpose: The carbohydrate-restricted diet has been recognized to be effective into preventing and alleviating lifestyle-related diseases, such as obesity and type 2 diabetes. The rare sugar ᴅ-allulose is a functional monosaccharide with anti-obesity effects. In the present study, we examined the effects of dietary ᴅ-allulose on body fat accumulation in rats fed severely carbohydrate-restricted diets containing high concentrations of different fats, beef tallow, or soybean oil. Methods: Male Wistar rats (n = 35, 3-week-old) were divided into 5 groups: One chow-fed control (C) group, and four carbohydrate-restricted groups, namely, beef tallow (B), beef tallow + ᴅ-allulose (BA), soybean oil (S), and soybean oil + ᴅ-allulose (SA), with free access to the diet and water for 8 weeks. The B and BA diets contained 23% beef tallow and 2% soybean oil, whereas the S and SA diets contained 25% soybean oil. Furthermore, the BA and SA diets contained 5% ᴅ-allulose. Results: The final body weight, weight gain, and food intake were significantly higher, and food efficiency was significantly lower in the control group compared to the other carbohydrate-restricted groups. Intra-abdominal adipose tissue, carcass fat, and total body fat weights were not influenced by dietary fat type or ᴅ-allulose supplementation, except for the epididymal adipose tissue weight. In contrast, carbohydrate restriction suppressed body weight gain in rats, but remarkably increased body fat accumulation. Conclusion: Under carbohydrate-restricted conditions, no anti-obesity effects of dietary ᴅ-allulose were observed, regardless of the dietary fat type. The causes of these effects are unknown. However, they may be influenced by a very low carbohydrate and high protein diet. Further research is required to elucidate the effects of ᴅ-allulose under various nutrient compositions with different fat, carbohydrate, and protein energy ratios.

• Animal Bioscience
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• v.37 no.6
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• pp.1031-1040
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• 2024

Objective: This study aimed to evaluate the effect of feeding milk replacer (MR) with varying levels of lactose and the increased supply of total solids (from 750 to 960 g/d) on performance, blood metabolites, and health of Holstein male calves during the preweaning period. Methods: Forty newborn Holstein calves (10 per treatment) were blocked according to birth weight and date of birth and distributed in a randomized block design to different liquid diets: Whole milk powder (WMP) diluted to 125 g/L solids; MR with 48% lactose (48L), diluted to 125 g/L solids; MR with 53% lactose (53L), diluted to 125 g/L solids; 53L MR corrected to 160 g/L solids (16TS) by the inclusion of a solid corrector. Calves were individually housed in wood hutches, fed 6 L/d of the liquid diet, and had free water and starter concentrate access. The study lasted 56 days. Results: Liquid diet intake was higher for calves fed 16TS than for other treatments. Calves fed 16TS presented higher protein and fat intake, followed by those fed WMP and the 48L or 53L MRs. Lactose intake was higher for 16TS-fed calves, followed by 53L, 48L, and WMP-fed calves. Starter and total dry matter intake did not differ among liquid diets. The average daily gain was higher for 16TS than 48L-fed calves, with the other treatments being intermediary. The lowest feed efficiency was observed for calves fed 48L. No effects on health were observed, as well as on selected blood metabolites, except for albumin concentration, which was higher for calves fed 16TS and WMP. Conclusion: Higher total solids content (160 g/L) in MR increases nutrient intake and consequently improves the performance of dairy calves. Feeding MRs with levels of lactose up to 53% of the DM had no deleterious effect on the performance or health of the calves.

• Journal of Bio-Environment Control
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• v.20 no.2
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• pp.123-133
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• 2011

The objective of this study was to find optimal nutrient condition of container seedling production of two tropical species for high seedling quality. This study was conducted to investigate photosynthesis, chlorophyll fluorescence, chlorophyll contents, and growth performances of container seedlings of Eucalyptus pellita and Acacia mangium growing under four different fertilization treatments (Con., $0.5\;g{\cdot}l^{-1}$, $1.0\;g{\cdot}l^{-1}$, and $2.0\;g{\cdot}l^{-1}$ fertilization). E. pellita showed outstanding photosynthetic capacity, photochemical efficiency, and chlorophyll contents at $1.0\;g{\cdot}l^{-1}$ fertilization. Meanwhile, E. pellita showed the highest photosynthetic capacity, photochemical efficiency, and chlorophyll contents at $2.0\;g{\cdot}l^{-1}$ fertilization, as fertilization rate were increased, those of A. mangium increased. Like physiological characteristics, Both E. pellita at $1.0\;g{\cdot}l^{-1}$ fertilization and A. mangium at $2.0\;g{\cdot}l^{-1}$ fertilization were higher root collar diameter, height, biomass, and seedling quality index than other treatments. These results showed that E. pellita at $1\;g{\cdot}l^{-1}$ fertilization and A. mangium at $2.0\;g{\cdot}l^{-1}$ fertilization is optimal nutrient condition, respectively. Moreover, fertilization rate controlling is very important for growth and seedling quality of container seedling.

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.8
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• pp.1160-1171
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• 2013

A feeding trial was conducted in tilapia to determine the growth performance, nutrient digestibility, digestive enzymes, and postprandial blood metabolites in response to different dietary amylose-amylopectin ratios. Five isonitrogenous and isolipidic diets containing an equal starch level with different amylose-amylopectin ratios of 0.11 (diet 1), 0.24 (diet 2), 0.47 (diet 3), 0.76 (diet 4) and 0.98 (diet 5) were formulated using high-amylose corn starch (as the amylose source) and waxy rice (as the amylopectin source). Each diet was hand-fed to six tanks of 15 fish each, three times a day over a 6-wk period. After the growth trial, a postprandial blood metabolic test was carried out. Fish fed diet 2 exhibited the highest percent weight gain and feed efficiency and protein efficiency ratio, whereas fish fed with diet 5 showed the lowest growth and feed utilization among treatments. The digestibility for starch in fish fed diet 1 and 2 was higher than those in fish fed with other diets (p<0.05). The highest activities for protease, lipase and amylase were found in fish fed the diet 2, diet 1, and diet 1 respectively among dietary treatments, while the lowest values for these indexes were observed in fish fed the diet 3, diet 5 and diet 4, respectively. The liver glycogen concentrations in fish fed diets 4 and 5 were found higher than in fish fed other diets (p<0.05). The feeding rate, hepatosomatic index, condition factor, and plasma parmeters (glucose, triglyceride, total cholesterol, high-density lipoprotein cholesterol, and low-density lipoprotein cholesterol) did not differ across treatments. In terms of postprandial blood responses, peak blood glucose and triglycerides were lower after 3 or 6 h in the fish fed with diets 3-5 than in the fish fed diet 1, but delayed peak blood total amino acid time was observed in fish fed with the diets 1 or 2. The lowest peak values for each of the three blood metabolites were observed in fish fed diet 5. The results indicate that high-dietary amylose-amylopectin ratio could compromise growth, but help in reducing the blood glucose stress on fish caused by postprandial starch load.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.12
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• pp.1711-1717
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• 2011

The objective of this experiment was to evaluate the effect of dietary supplementation of glutathione (GSH) on health, solid feed consumption, nutrient intake, body weight gain (BWG), feed efficiency, blood metabolites and the occurrence of diarrhea in Holstein neonatal calves. The calves were fed plain milk as a control (CON) or milk with GSH supplementation. Sixteen calves were separated from their mothers immediately after birth, moved into individual cages and fed colostrum for the first three days. For GSH supplementation, three grams of GSH powder were mixed in 1.8 L of heat-treated milk and placed in a plastic bottle with a rubber nipple. The calves were fed GSH-supplemented milk only once out of four daily feedings. For the first 25 d, calves were fed 1.8 L of milk four times per day. Milk feeding frequency was reduced to three times per day from days 26 to 30, followed by twice a day from days 31 to 44, and once a day from days 45 to 49, after which they were weaned at day 50. Body weight gain (BWG), feed consumption, and growth performance were monitored until day 70. The dietary supplementation of GSH had no effect on daily feed intake and growth performance in growing calves. Hematological results revealed red blood cell distribution width (RDW) was lower, and mean corpuscular volume (MCV) was significantly higher in calves fed GSH. Serum lactate dehydrogenase (LDH) concentrations were lower in calves fed GSH. Rectal temperature at day 70 was higher in calves that did not receive GSH, while mean frequency of diarrhea and enteritis was less in calves fed GSH. It is concluded from the present study that BW gain, total dry matter intake (DMI), feed efficiency, and breathing rate did not differ between groups. However, there were some positive blood parameters and the mean frequency of diarrhea and enteritis was less in calves fed GSH compared to CON which did not receive GSH. With the results obtained, supplementation of GSH is highly recommended.

• Korean Journal of Soil Science and Fertilizer
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• v.27 no.2
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• pp.78-84
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• 1994

Yield response of tomato to nitrogen and potassium fertilizer and the balance of the two elements were determined in salt-accumulated greenhouse soil to improve the efficiency of fertilizer appiication. The response of tomato yield to nitrogen and potassium fertilizer application was not significant. The current parameters such as OM and $K/{\sqrt{Ca+Mg}}$ that were used to determine the level of nitrogen and potassium fertilizer in open field were not suitable in salt-accumulated greenhouse soil condition. The temporal and spatial distribution of $NO_3{^-}-N$showed the same pattern to those of $Cl^-$ ion that is non-reactive with soil, while the content of Ex. K was extraordinarily high in soil after harvesting of tomato, which had experienced relatively dry condition during harvesting time. The loss of $NO_3{^-}-N$ and Ex. K out of 28cm below the soil surface was 2~5 and 1.5~3.5 times greater than the amount of nitrogen and potassium uptake by the plant.

• Journal of Animal Science and Technology
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• v.51 no.1
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• pp.39-44
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• 2009

The objective of this study was to investigate the effects of an enriched diet supplemented with aqueous fibrolytic enzyme products (FEP) on In vitro fermentation and growth performance of Hanwoo Steers. Total mixed ration combined with fibrolytic enzyme products showed a slight increase in the pH level on In vitro fermentation. Acetate ratio in volatile fatty acids, and the concentration of total volatile fatty acids were significantly greater at 12hr and 24hr after cultivation (p<0.05). Dry matter digestibility was significantly increased in groups supplied with aqueous fibrolytic enzyme products at 24hr after cultivation (p<0.05). In a rearing trial, the average daily gain and feed efficiency improved in the treatment groups supplied with aqueous fibrolytic enzyme products. Nutrient digestibility such as DM, crude fiber, NDF, and ADF digestibility were also significantly increased with the addition of aqueous fibrolytic enzyme products (p<0.05). Therefore, the aqueous fibrolytic enzyme products supplementation on In vitro fermentation is effective in improving the condition of rumainal fermantation. Also two kinds of aqueous fibrolytic enzyme products were found to be effective in improving the average daily gain and feed efficiency in Hanwoo Steers.