• Title/Summary/Keyword: nutrient change

Search Result 549, Processing Time 0.034 seconds

Causes and Overcoming of the Algae Excess in a Dam Water - Based on the Data of Water Quality Analysis of Mulgum Area - (댐호화된 하천의 조류 과다 발생원인과 해소 방안 - 낙동강 물금 지역의 수질 분석 데이터를 중심으로 -)

  • Yang, Shi-Chun;Xia, Tian-Tian;Kang, Tai-Ho
    • Journal of the Korean Society of Environmental Restoration Technology
    • /
    • v.20 no.4
    • /
    • pp.1-13
    • /
    • 2017
  • The purpose of this study is to analyze a term of decade of water quality data of the Mulgum intake station on the Nakdong river(dam) to find the cause of algal blooms and to set an alternative to prevent artificial lake water pollution. Our study shows that water quality changes have regular periodic regularity and there was a certain correlation between specific analytical items. According to the analysis results of each factor, the decline in precipitation was not the main reason for algal blooms. TP concentration had a slight effect on Chl-a concentration but was not a limiting nutrient of a bloom. TN concentration had a strong correlation with Chl-a and strongly negative correlation with temperature, but was not a bloom's limiting nutrient, and was only a dependent variable. As the temperature was negatively correlated with the Chl-a concentration, it is found that the aspect of the ecological influence of the temperature was the most important factor of the phytoplankton concentration change. The N/P ratio lies under a power function with a high degree of reliability by the TP concentration, and the phenomenon appeared to be the same as the results of two other comparative areas. This result confirms that TN is dependent on TP and the biota in the lake that TN is a dependent variable whose concentration is determined by TP it. In conclusion, the increase in lake bloom is the result of a food chain change, and it is necessary to control the ecosystem by the food chain in the lake in order to reduce the lake's bloom. In particular, it is important to keep the benthic ecosystem as wide as possible in the aerobic state.

Assessment of The Above-Ground Carbon Stock and Soil Physico-Chemical Properties of an Arboretum within The University of Port Harcourt, Nigeria

  • Akhabue, Enimhien Faith;Chima, Uzoma Darlington;Eguakun, Funmilayo Sarah
    • Journal of Forest and Environmental Science
    • /
    • v.37 no.3
    • /
    • pp.193-205
    • /
    • 2021
  • The importance of forests and trees in climate change mitigation and soil nutrient cycling cannot be overemphasized. This study assessed the above-ground carbon stock of two exotic and two indigenous tree species - Gmelina arborea, Tectona grandis, Khaya grandifoliola and Nauclea diderrichii and their litter impact on soil nutrient content of an arboretum within the University of Port Harcourt, Nigeria. Data were collected from equal sample plots from the four species' compartments. Tree growth variables including total height, diameter at breast height, crown height, crown diameter and merchantable height were measured for the estimation of above-ground carbon stock. Soil samples were collected from a depth of 0-30 cm from each compartment and analyzed for particle size distribution, organic carbon, total nitrogen, available phosphorus, exchangeable bases, exchangeable acidity, cation exchange capacity, base saturation, pH, Manganese, Iron, Copper and Zinc. Analysis of Variance (ANOVA) was used to test for significant difference (p<0.05) in the carbon contents of the four species and the soil nutrient contents of the different species' compartments. Pearson correlation was used to assess the relationships between the carbon contents, growth parameters and soil parameters. The highest and lowest carbon stock per hectare was observed for G. arborea (151.52 t.ha-1) and K. grandifoliola (45.45 t.ha-1) respectively. Cation exchange capacity and base saturation were highest and lowest for soil under G. arborea and K. grandifoliola respectively. The pH was highest and lowest for soil under G. arborea and T. grandis respectively. Carbon stock correlated positively with dbh, crown diameter, merchantable height and Zn and negatively with base saturation. The study revealed that G. arborea and N. diderrichii can effectively be used for reforestation and afforestation programmes aimed at climate change mitigation across Nigeria. Therefore, policies to encourage and enhance their planting should be encouraged.

Changes of Basic Food Groups accoriding to the Revision of Korea RDAs (한국인 영양 권장량의 개정에 따른 기초식품군의 변화)

  • Kang, Hae-Kyung
    • Journal of the Korean Society of Food Culture
    • /
    • v.12 no.4
    • /
    • pp.365-374
    • /
    • 1997
  • Due to the continuous change of socio-economic circumstances and dietary pattern, the need to change recommended dietary allowances and the basic food groups has been required. Consequently, there have been six revisions of the Korea RDAs, the national recommanded dietary allowances. I reviewed the six sequences of revisions concerning the basic food groups. Up to the fifth revision, the ranks of the basic food groups were based upon the dietary needs of the people of the perspective era. However, in the sixth revision, there was no rank associated with the food groups, but the food groups were portrayed in a food composition tower that explained their importance and their necessary consumption amounts. I could indirectly observe the dietary pattern of each era by analyzing the basic food groups and the representative foods of each food group. I also studied information of pictorial representations of the basic food groups and compared the items of the representative foods with nutrient analysis table. By observing nutrient analysis table, I analyzed whether the clarified representative foods of the basic food groups are indeed foods that were eaten frequently by people daily.

  • PDF

Analyses on the Factors Related to Stages of Dietary Behavioral Changes among Child Bearing Aged Women (가임여성에서 식행동 변화단계에 따른 식생활 요인 분석)

  • 권성옥;오세영
    • Journal of Nutrition and Health
    • /
    • v.36 no.7
    • /
    • pp.759-768
    • /
    • 2003
  • This study examined the factors related to stages of dietary behavioral changes among 1449 child bearing aged women (mean age $\pm$ SD = 25.6 $\pm$ 5.3 years) residing in large cities. A self administered questionnaire was used to assess stages of dietary behavioral change, meal balance and regularity, food availability, nutrition knowledge, body mass index, nutrient intake, and psycho-social factors including self efficacy, perceived benefits and barriers, social modeling. Undesirable dietary behaviors (precontemplation and contemplation) were shown among 45.1-57.4% of the participants, among those, 33.4-43.0% were precontemplators. Participants' self efficacy scores associated with dietary changes were higher in specific situations (3.42) as compared to general situations (2.86). Similarly, they appeared to perceive more benefits (3.86) rather than barriers (2.76) by changing their inappropriate eating habits. Perception and accuracy scores of nutrition knowledge were relatively high, indicating 90.9 and 80.1, respectively. In terms of food availability at home, fresh fruits received the highest score, followed by milk and milk products, vegetables, meat, alcoholic beverages and soft drinks. In social modeling assessment, family members, as compared to friends, appeared to have better dietary habits. Stages of dietary behavioral change assessed in terms of meal regularity were associated with nutrient intake, showing higher energy and carbohydrate intakes but lower fat intake among those who belonged to the action and maintenance stage. They also presented higher self efficacy and perceived more benefits and less barriers regarding the change of undesirable eating habits. Fresh meat and vegetables were more available among those maintaining desirable dietary habits. Results of this study presented the significant relations of motivational and reinforcing social factors with stages of dietary behavioral changes and a need for the development of tailored nutrition education program considering these factors for child-bearing aged Korean women.

Long-term Ecological Research Programme in Forestry Research Institute, Korea

  • Oh, Jeong-Soo;Shin, Joon-Hwan;Lim, Jong-Hwan
    • The Korean Journal of Ecology
    • /
    • v.23 no.2
    • /
    • pp.131-134
    • /
    • 2000
  • Forest vegetation in Korea can be largely divided into warm temperate, cool temperate and frigid forest zone. The cool temperate forest zone of them occupies the largest part of the Korean peninsula and it is generally divided into three subdivisions such as northern, central and southern subzone. The Forestry Research Institute established three long-term ecological research sites at Kwangnung Experiment Forest in the central subzone of the cool temperate forest zone, at the Mt. Kyebangsan Forest in the northern subzone of the cool temperate forest zone. and at the Mt. Keumsan Forest in the warm temperate forest zone. The objectives of long-term ecological research in the Forestry Research Institute, Korea are to study long-term changes of the forest ecosystems in energy fluxes, water and nutrient cycling, forest stand structure, biological diversity, to quantify nutrient budgets and fluxes among forest ecosystem compartments and to integrate ecological data with a GIS - assisted model. To achieve the objectives, forest stand dynamics. environmental changes in soil properties, stream water quality, nutrient cycling, air pollution and biological diversity have been investigated and plant phonology as an indicator of climate change has been monitored in the LTER sites.

  • PDF

Feeding Sesbania Leaves as a Sole Feed on Growth and Nutrient Utilization in Goats

  • Shahjalal, M.;Topps, J.H.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.13 no.4
    • /
    • pp.487-489
    • /
    • 2000
  • An experiment was conducted for 56 days using nine castrated male Black Bengal goats (initial live weight 9.0 kg) aged about 5 months to study the effects of feeding Sesbania leaves as a sole feed on growth performance and nutrient utilization. The animals were fed ad libitum on either road-side grass, Sesbania aculeata leaves or Sesbania rostrata leaves. Average dry matter (DM) intake was 179, 229 and 259 g/d for goats fed road-side grass, Sesbania aculeata and Sesbania rostrata, respectively. Corresponding mean values for average daily live weight change were -6.6, 9.5 and 38.1 g, respectively. These values were higher (p<0.05) for goats fed Sesbania leaves than those given road-side grass. The apparent digestibility of all the proximate components except CF and the concentrations of DCP, TDN, DOM and ME of Sesbania leaves were higher (p<0.05) than those of road-side grass. Sesbania rostrata was superior (p<0.05) to Sesbania aculeata for nutrient digestibilities (except for NFE) and also for DOM, DCP and ME concentrations. Therefore, it may be concluded that the production of Sesbania rostrata, a legume fodder, should be encouraged for feeding goats.

Effects of Simulated Acid Rain and Soil Fertilizers on Photosynthetic Rate, wax Content, and Contact Angle of Japanese Red Pine(Pinus densiflora Sieb. et Zucc.) Leaves (인공산성우와 토양시비가 소나무잎의 광합성속도, 왁스 함량 및 접촉각에 미치는 영향)

  • 최기영;이용범;채의석;이경재
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.12 no.3
    • /
    • pp.263-268
    • /
    • 1996
  • This study was conducted for the assessment of the effects of acid rain and soil fertilizers on photosynthetic rate, was content, and contact angle on 5-year seedlings of Japanese red pine (Pinus densiflora Sieb. et Zucc.) leaves. The seedlings were exposed to pH 3.0 (simulated acid rain), pH 6.5 (groung water) and rain (pH around 4.6). The seedlings were also treated with $Ca(OH)_2, Mg(OH)_2, and Ca(OH)_2 + Mg(OH)_2 + C.F.(compound fertilizer)$. Photosynthetic rate, stomatal conductance, was content, contact angle value, and mineral nutrient content of the leaves were measured and the results were as follows: 1. Photosynthetic rate and stomatal conductance of the leaves increased with the increase of pH. Photosynthetic rate and stomatal conductance increased with application of soil fertilizer in the pH 3.0 treatment, but showed no changes in the rain and the pH 6.5. 2. Contact angle value and was content of the leaves did not change with the pH treatment, but increased with the fertilizer treatments. 3. Mineral nutrient contents of the leaves were lowest in the rain treatment and highest in the pH 6.5 treatment. The increase of mineral nutrient contents was observed with the soil fertilizer treatments.

  • PDF

Effects of periodic air-exposure and nutrients on the competition of Ascophyllum nodosum and Fucus vesiculosus germlings

  • Park, Seo Kyoung;Choi, Han Gil;Nam, Ki Wan
    • Korean Journal of Environment and Ecology
    • /
    • v.29 no.1
    • /
    • pp.7-13
    • /
    • 2015
  • To examine the relationship between competition and environmental factors, the germlings of Ascophyllum nodosum (L) Le Jolis and Fucus vesiculosus L. were cultured in monocultures and mixtures of the two species under two different exposure and nutrient levels. Both intra- and inter-specific competition were examined in comparison of the mortality and growth of germlings in monocultures and mixtures of the two species. The mortality of germlings increased with increasing density and emergence periods both in the monoculture and mixtures of the two species, and the mortality of Ascophyllum was significantly higher than that of Fucus both in submerged and emerged treatments. The growth of germlings of both species reduced with increasing density but F. vesiculosus always grew faster than Ascophyllum. The values of log output ratio were more than 0.1, indicating that Fucus 'won' in the competitive battles with Ascophyllum under two nutrient- and air-exposure levels. Log output ratio was greater in high than in low nutrients, indicating that the growth of Fucus is more enhanced than that of Ascophyllum in high nutrients. In the present study, the outcome of inter specific competition between germlings of Fucus vesiculosus and Ascophyllum nodosum was slightly altered by duration of emergence and nutrient concentration, but not to such an extent as to change the outcome.

Development of Program Based on the Website for Individual Meal Planning (개인별 식사계획을 위한 웹 기반 프로그램 개발)

  • Kim, Jung-Mi;Choi, Soo-Kyong;Seo, Jung-Sook
    • Korean Journal of Community Nutrition
    • /
    • v.14 no.1
    • /
    • pp.31-42
    • /
    • 2009
  • The purpose of this study was to develop the website-based program for individual meal planning. The program consisted of the basic information of clients, dietary habits, analysis of nutrient intakes and menu planning. The first part of the program consisted of general information such as general characteristics and anthropometric data of clients. The second part was designed to investigate the dietary habits, food intake frequency, nutrition knowledge, and drinking and smoking habits of the clients. The third part consisted of analysis of nutrient intakes including three major nutrients, calorie intake by foods and alcohol, and ratio of individual fatty acid intake. Nutrient intakes was evaluated by comparing with dietary reference intakes. In the final part, the program included the menu planning by using standard recipe. This system was also designed to insert, remove or change the food items or amount according to the user need. It is expected that the development of a meal planning system based on the internet can facilitate the professional dietary counseling, and thus help to improve the health of people.

Effects of light and nutrient on flower formation and vegetative growth of Viola collina

  • Park, Hyekyung;Son, Ga-yeon;Kim, Jae Geun
    • Journal of Ecology and Environment
    • /
    • v.46 no.3
    • /
    • pp.243-249
    • /
    • 2022
  • Background: Mixed breeding herb Viola collina Besser, which produces both chasmogamous and cleistogamous flower, has limited habitats under closed canopy and short and early flowering timing, making it relatively more vulnerable to climate change. To better understand the effect of light and nutrient on the flower formation and vegetative growth of V. collina, a mesocosm experiment was conducted. Two-by-two factorial treatments of two light conditions (100% and 60% of natural light) and two fertilizer treatment conditions (fertilized and not fertilized) were applied in the mesocosm experiment. Results: The number of flowers, including chamogamous and cleistogamous flowers, was highest (5.65/pot) under 60% light and fertilized condition and lowest (1.41/pot) under 100% light and not-fertilized condition. However, above ground vegetative growth was highest (2.89 g/pot) under 100% light and fertilized condition and lowest (2.38 g/pot) under 60% light and not-fertilized condition. Above ground biomass to belowground biomass ratio was highest (1.50) under 60% light and fertilized condition and lowest (1.26) under 100% light and fertilized condition. Conclusions: This study showed that high light and nutrient are responsible for the vegetative growth, though the effect of fertilizer was reduced due to allocation and retainment of nutrients. In addition, the low light is necessary to make flowers, especially chasmogamous flowers.