• Journal of Forest and Environmental Science
• /
• v.35 no.2
• /
• pp.121-139
• /
• 2019

Decomposition of litter is a function of various interrelated variables, both biotic and abiotic factors. Litter decomposition acts like a natural fertilizer play a prime role in maintaining the productivity and nutrient cycling in agroforestry systems. There are few studies of decomposition carried out in agroforestry systems with coffee; so it is necessary to perform more research work to fill the research gap, which will allow a better understanding of the management of the coffee agroforestry systems. This paper is based on the theoretical and conceptual aspects of leaf litter decomposition in agroforestry systems, emphasizing the combination with coffee cultivation and critically examined the role of the different factors involved in the decomposition. This study made a comparison of different investigations with regards to weight loss, decomposition rates (k), initial chemical composition, and release of the main nutrients. This study suggested that it is necessary to implement studies of decomposition and mineralization, and the microflora and fauna associated with these processes, so that serves as an important tool to develop a model for enabling a description of the short, medium, and long-term dynamics of soil nutrients in coffee agroforestry systems.

• Animal Bioscience
• /
• v.36 no.10
• /
• pp.1546-1557
• /
• 2023

Objective: The present study aimed to evaluate the effects of extruded and unextruded feeding on the performance, milk composition, digestibility and ruminal fermentation of dairy cows through a meta-analysis. Methods: The database was compiled from 53 studies in Scopus and PubMed. The data were analyzed using a random effects model in OpenMEE software. Extruded feed was grouped as the experiment group while and the others as control group. The bias of publication in the main parameter of dairy performance was evaluated by a funnel plot. Results: The result showed that extruded feed enhanced the milk yield, dry matter and crude protein digestibility, butyrate and valerate acid production (p<0.05). Meanwhile, the extruded feed significantly decreased the milk fat and protein concentration (p<0.05). Also, the iso-butyrate and iso-valerate in unextruded feeding was significantly higher than the extruded feed (p<0.05). Conclusion: It was concluded from the meta-analysis that extruded feed effectively improved the milk production and milk lactose concentration, dry matter and protein digestibility, but not the milk fat and protein concentration.

• Journal of Plant Biotechnology
• /
• v.45 no.4
• /
• pp.289-298
• /
• 2018

The Biosafety Division of the National Academy of Agricultural Science has developed a 'Crop Composition DB' that provides analytical data on commercialized crops. It can be used as a reference in the 'Comparative Evaluation by Compositional Analysis' for the safety assessment of genetically modified (GM) crops. This database provides the composition of crops cultivated in Korea, and thus upgrades the data to check the extent of changes in the compositional content depending on the cultivated area, varieties and year. The database is a compilation of data on the antioxidant, nutrient and secondary metabolite compositions of rice and capsicum grown in two or more cultivation areas for a period of more than two years. Data analysis was conducted under the guidelines of the Association of Official Analytical Chemists or methods previously reported on papers. The data was provided as average, minimum and maximum values to assess whether the statistical differences between the GM crops and comparative non-GM crops fall within the biological differences or tolerances of the existing commercial crops. The Crop Composition DB is an open-access source and is easy to access based on the query selected by the user. Moreover, functional ingredients of colored crops, such as potatoes, sweet potatoes and cauliflowers, were provided so that food information can be used and utilized by general consumers. This paper introduces the feature and usage of 'Crop Composition DB', which is a valuable tool for characterizing the composition of conventional crops.

• Journal of Bio-Environment Control
• /
• v.17 no.2
• /
• pp.162-169
• /
• 2008

To determine suitable composition of nutrient solution according to soil textures in fertigation culture of cucumber using three strengths (S) of Yamasaki cucumber recipe, chemical changes of soil, growth characteristics and yield of cucumber were investigated. Electric conductivity of drainage solution was risen in all treatments, pH of loam soil was generally optimum level and that of sandy soil was high level. Photosynthetic rate in loam soil supplied the 1/2 S and transpiration rate in sandy soil supplied the 1.0 S were most low. Diffusive resistance in sandy soil supplied the 1.0 S was high. Chlorophyll contents was higher concentrations by the kinds of soil. Amount of drainage solution in sandy loam soil supplied the 1/2 S and loam soil supplied the 1.0 S were most much and little, respectively. Water absorption rate was the opposition to amount of drainage solution. Nutrient contents in soil except calcium were most high in the 1.0 S by the kinds of soil. Nutrient contents in leaves, nitrogen in sandy soil supplied 1.0 S, phosphorus in loam soil supplied 1/2 S, potassium in two soil supplied 1.0 S, calcium in loam supplied 1/2 S and sandy loam soil supplied 1.0 S, magnesium in loam soil supplied the 1/2 S was high. The growth and yield of fruit were more in loam than in sandy loam soil. Therefore, the suitable compositions of macro-nutrients for fertigation culture of cucumber were determined in loam and sandy loam soils as follows: In loam soil, they were $NO_3$-N 12.3, $NH_4$-N 1.0, P 3.0, K 5.9, Ca 5.7, Mg $3.5\;me{\cdot}L^{-1}$, whereas in sandy loam soil $NO_3$-N 11.7, $NH_4$-N 1.0, P 3.0, K 5.9, Ca 4.9, Mg $3.2\;me\;L^{-1}$.

• Journal of Bio-Environment Control
• /
• v.26 no.4
• /
• pp.393-401
• /
• 2017

The nitrate ($NO_3{^-}$) accumulation of hydroponically grown leafy vegetables may increase in the condition of a closed-type plant production system with low light intensity due to low activity of enzymes involved in nitrogen assimilation and the use of $NO_3-N$ as major nitrogen source. The objective of this study is to investigate the effects of light intensities, nutrient solution compositions and the time of nutrient solution removal before harvest on nitrate contents of hydroponically-grown lettuces in a closed plant production system. The reduction of nitrate contents in leafy lettuces 'Cheongchima' was higher in the treatments of 'TW' (nutrient solution removal) and '$(NH_4)_2CO_3$' (use of ammonium carbonate as nitrogen source) than those in other treatments, which significantly lowered fresh weight and leaf area of the plants. In the light intensity of $100{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, the nitrate content was effectively reduced without causing any growth retardation, by substitution of the nutrient solution composition that $NO_3-N$ was removed ('$NO_3-N$ removal' treatment) or the half strength of standard nutrient solution was applied ('1/2 S' treatment), for 7days before harvest. The effects of light intensity and the time of nutrient solution removal before harvest on growth and nitrate contents in leafy lettuces were investigated. The nitrate contents in leaves under the light condition of $300{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ before nutrient solution removal were lower than those of 100 or $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$. The removal of nutrient solution for 7 days before harvest quickly reduced the amount of nitrates in leaves in all the light intensities with a greater degree under the $300{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ of light condition, while the 7 days-removal with both 200 and $300{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ of light conditions caused decrease in 16~31% of leaf area and 20~35% of fresh weight, compared to the 3 days-removal treatment. The nitrate contents were greatly reduced from 3,018 to 1,035 in $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, and 2,021 to 480 ppm in the light condition of $300{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$, with the nutrient solution removal for 3 days before harvest, without causing any deterioration in growth and product quality. The vitamin C contents in leaves were higher in the treatment of nutrient solution removal for both 3 and 5 days before harvest with the light condition of $300{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ than those in the light condition of 100 or $200{\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.5
• /
• pp.720-732
• /
• 2001

Skeletal muscle is of major economic importance since it is finally converted to meat for consumers. The increase in meat production with low costs of production may be achieved by optimizing muscle growth, whereas a high meat quality requires, among other factors, the optimization of intramuscular glycogen and fat stores. Thus, research in energy metabolism aims at controling muscle metabolism, but also liver and adipose tissue metabolism in order to optimize energy partitioning in favour of muscles. Liver is characterized by high anabolic and catabolic rates. Metabolic enzymes are regulated by nutrients through short-term regulation of their activities and long-term regulation of expression of their genes. Consequences of liver metabolic regulation on energy supply to muscles may affect protein deposition (and hence growth) as well as intramuscular energy stores. Adipose tissues are important body reserves of triglycerides, which result from the balance between lipogenesis and lipolysis. Both processes depend on the feeding level and on the nature of nutrients, which indirectly affect energy delivery to muscles. In muscles, the regulation of rate-limiting nutrient transporters, of metabolic enzyme activities and of ATP production, as well as the interactions between nutrients affect free energy availability for muscle growth and modify muscle metabolic characteristics which determine meat quality. The growth of tissues and organs, the number and the characteristics of muscle fibers depend, for a great part, on early events during the fetal life. They include variations in quantitative and qualitative nutrient supply to the fetus, and hence in maternal nutrition. During the postnatal life, muscle growth and characteristics are affected by the age and the genetic type of the animals, the feeding level and the diet composition. The latter determines the nature of available nutrients and the rate of nutrient delivery to tissues, thereby regulating metabolism. Physical activity at pasture also favours the orientation of muscle metabolism, towards the oxidative type. Consequently, breeding systems may be of a great importance during the postnatal life. Research is now directed towards the determination of individual tissue and organ energy requirements, a better knowledge of nutrient partitioning between and within organs and tissues. The discovery of new molecules (e. g. leptin), of new molecular mechanisms and of more powerful techniques (DNA chips) will help to achieve these objectives. The integration of the different levels of knowledge will finally allow scientists to formulate new types of diets adapted to sustain a production of high quality meat with lower costs of production.

• Korean Journal of Environmental Agriculture
• /
• v.27 no.3
• /
• pp.253-259
• /
• 2008

Soil environmental conditions can affect nutrient availability during growth stage of tree fruit. We investigated the cause of disorderd fruit by the influence of soil chemical properties in orchard soil, composition of mineral nutrient in leaves and fruit to occur physiological disorderd fruit at four locations (Ulsan, Gyeongju, Pyeongtaek, Ansung) compared to healthy. There were significantly different (P=0.05) in exchangeable Ca, K, Mg and total nitrogen content in orchard soil between physiological disordered fruit and healthy fruit. The exchangeable Ca content in orchard soil caused by physiological disordered fruit was statistically lower than that of healthy fruit. However, exchangeable K, Mg and total nitrogen contents were higher than that healthy (P=0.05). There was a significant difference (P=0.05) in Ca content between physiological disordered fruit and healthy. Ca content in fruit flesh of physiological disorderedfruit was statistically lower than that of healthy. The physiological disordered fruit was a higher ratio of Mg/Ca in fruit flesh and peel compared to healthy fruit and also the ratios of N/Ca and K/Ca in a leaf were higher. The negative correlation between Ca and K, and Ca and Mg was detected in the fruit flesh of physiological disordered fruit. Therefore, we concluded that insufficient Ca content in fruit may cause 'the physiological disorder' pomelo disease and high content of N, exchangeable K and Mg ion in the soil solution might be disturbs exchangeable Ca ion to be absorbed in fruit.

• Journal of Korean Society of Environmental Engineers
• /
• v.39 no.5
• /
• pp.288-302
• /
• 2017

Accurate measurement of benthic nutrient fluxes (BNF) is a prerequisite for evaluating the effect of sediments on nutrient cycle in the surface water. The intact sediment cores were collected in July 2015 at the midstream of Nakdong River. We identified pre-incubation time (6, 12, 24 hr), dissolved oxygen concentration (90, 70, 50% saturation), diffusive boundary layer thickness (0, 0.6-0.8, 1.2-1.4 mm), and incubation temperature (10, 17, 20, $25^{\circ}C$) as the most important control factors, and measured the BNF fluctuation with the variation of these factors using the laboratory sediment core incubation method. Since the chemical composition, redox condition, hydrodynamic regimes and microbial activities at the sediment-water interface were changed as a result of the alteration of control factors, sediment core incubation should be conducted under as close to the natural conditions of study site as possible, in order to produce the results similar to actual values. Relative percentage differences between two replicates were below 20% in most control factors, which showed satisfactory precision for strict compliance with the experimental conditions and procedures. In the further studies, we will compare the results of core incubation with those of in situ measurements to confirm the accuracy of the sediment core incubation method.

• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.42 no.3
• /
• pp.276-283
• /
• 2009

Enrichment in nutrients coming from urban sewage outfalls can lead to eutrophication in coastal areas, which can also change the species composition and community structure of macro algal communities. We investigated the structure of the macro algal community within three rocky shores in order to assess any possible differences in their characteristics. Site 1 was located near Tongyeong city's sewage outfall, Site 2 was located near a public beach area, and Site 3 faced open channel of the Ocean. All three sites were located within the same stretch of the coast, where Site 2 was located between sites 1 and 3. We measured the nutrient concentration in water and the tissue nitrogen content in macro algae samples. Nutrients in the water column surrounding site 1 were high in ammonium ($30.2\pm1.8{\mu}M$), nitrate ($26.2{\pm}0.1{\mu}M$), and phosphate ($2.7{\pm}0.1{\mu}M$) content, and were characterized by low numbers of macroalgal species and species and a low species diversity index. In contrast, site 3 exhibited relatively low nutrient concentration levels and a high number of macroalgal species and a high species diversity index. Comparative analysis showed that the tissue nitrogen content of macroalgae were significantly (P<0.05) affected by the nutrient concentration in the water column. The tissue nitrogen content of green algae within site 1 was higher than the others sites. However, the tissue nitrogen content of brown algae was similar at all three sites. Thus, the tissue nitrogen content of macro algae and the macro algal community structure of intertidal rocky shores were dependent on location and the performance of macroalgal communities was dependent on water quality.

• Journal of Nutrition and Health
• /
• v.30 no.10
• /
• pp.1203-1210
• /
• 1997

This study was performed from March to June 1994 in ANsung Medical Center. We investigated serum components of 78 diabetics in the center, in addition to the nutrient intake status and anthrophometric status of 60 diabetics among them. We separated the latter into 2 groups(ⅰ) less tan 5 years of diabetic duration and ⅱ) more than 6 years of diabetic duration) and analyzed the clinical characteristics of each group. The results are as follows : \circled1 The average ages of male and female subjects were 57.1 and 58.9 years, respectively. The average diabetic duration of male subjects was 4.8 years and that of female subjects was 5.9 . The major occupational field of both male and female subjects was agriculture(33.3%, 36.1%). 50% of male and 75% of female subject's monthly incomes were less than 600, 000 won and 75% of male and 94.4% of female subjects had weekly food expense less than 40, 000 won. The nutrient intake status of the subjects was lower than RDA on the whole. There was no big differences between 2 the male groups of different diabetic duration , but calorie, protein , fat carbohydrate, phosphorus, iron and Vit B$_1$intakes of the above 6 year female group were appearently higher than those of the under 5 year female group (p<0.05). There were different intake tendencies between male and female subjects . For females. the longer the diabetic duration, the less intakes of calorie, protein , fat carbohydrate, phosphorus, iron Vit B$_1$, Vit B$_2$, and niacin were observed. Furthermore, the longer the diabetic duration in females , the more intakes of energy and nutrients, except Vit C were observed. Fasting blood glucose levels were 155mg/dl and 164mg/dl and Postprandial glucose levels were 242mg/dl and 247mg/dl for males and females respectively. Hb of both males and females , and Ht of males met the lower limit of normal status, The serum TG level was higher than normal , so that they seemed to suffer from hyperlipidemia ; their high HbAIC status indicated that the management of diabetes mellitus was poor. The total protein level of female subject was higher when compared with that of males(p<0.05). All subjects blood pressure were higher than normal , and the longer the diabetic duration, the higher was the blood pressure. The serum HDL-cholesterol levels of the above 6 year group male subjects were lower(p<0.05) than those of the under 5 year male group subjects, and the former group's systolic and diastolic blood pressures were higher than those of the latter(p<0.05). Levels of serum total protein, albumin and TG of the above 6 year female group were lower than those of the under 5 year female group(p<0.05). As the diabetic duration was extended, HDL-cholesterol and LDL-cholesterol levels showed a tendency to increase, while Hb, Ht, total protein, albumin, and A/G, which represent the nutrients state of iron and protein, were inclined to decrease. This result showed that serum lipid components went bad. To summarize the results, the longer the diabetic duration, the worse were the male subjects nutrient intake status, but those of the female subjects were good. With respect to serum components and serum lipid subjects Fe, protein, nutrition status and serum lipid component got worse as the diabetic duration was extended , implying the possibility of diabetes mellitus complication grows.