• Title, Summary, Keyword: Litter quality

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The Aspect of Natural Regeneration for Major Tree Species in the Natural Deciduous Forest (천연문엽수임내(天然聞葉樹林內) 주요(主要) 구성(構成) 수종(樹種)의 천연경신(天然更新) 양상(樣相))

  • Kim, Ji Hong;Yang, Hee Moon;Jin, Guang Ze;Lee, Won Sup;Kang, Sung Kee
    • Journal of Forest and Environmental Science
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    • v.17 no.1
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    • pp.1-17
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    • 2001
  • Forming a part of "Cooperative Practical Study for the Modernization of the Management of National Forest", this study was conducted to provide overall ecological information for the natural regeneration of major tree species on the basis of community structural attributes in the deciduous forest ecosystem. Followings are summarized characteristics of the natural regeneration for the selected tree species. Betula costata : Although large number of seeds are dispersed by wind, they require mineral soils to germinate. Thick litter layer could be an obstacle to germinate. After germination, the seedling requires large amount of light for successful establishment. Acer mono : Characterized by high shade tolerance and weak drought resistance, the seedling should be overcasted with more than 50% of canopy coverage. High stand density should be maintained to produce good quality of timber. The potential of coppice may be high. Ulmus laciniata : Since this species needs high rate of troll moisture and light, around 60% of canopy coverage should be maintained to retain moisture and incoming light. The competition with other vegetation should be removed for the favor of successful seedling establishment. Fraxinus mandshurica : This species requires moist mineral soils to germinate. After germination, the seedling needs large amount of light and moisture for successful establishment. Site preparation should be applied to reduce competition with weedy vegetation. Fraxinus rhynchophylla : Interval of large seed crops may be highly varied. Thick litter layer could be an obstacle to germinate. Site preparation should be applied to reduce competition with weedy vegetation so as to achieve successful seedling establishment. Quercus mongolica : Including the difficulty of seed supply by the consumption, thick litter layer and mountain bamboo cover could be the obstacle to germinate. More than 50% of relative light intensity is necessary to achieve successful seedling establishment. Kalopanax pictus : Thick litter layer could be an obstacle to germinate. The seedling needs large amount of light and moisture for successful establishment. Abies holophylla : In spite of high shade tolerance, the growth rate in sapling stage may be extremely slow. Cornus controversa : Seeds (drups) are consumed and dispersed by animals, tending to be not sufficient in seed supply. This species requires large amount of light for successful germination and seedling establishment. Tilia amurensis : The difficulty of seed supply might be expected with low seed purity and double dormancy. Since thick litter layer could be an obstacle to germinate, the species requires moist mineral soils for successful germination. The potential of coppice may be extremely high.

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Effects of Expander Conditioning of Corn- and Sorghum-Based Diets on Pellet Quality and Performance in Finishing Pigs and Lactating Sows

  • Johnston, S.L.;Hancock, J.D.;Hines, R.H.;Kennedy, G.A.;Traylor, S.L.;Chae, B.J.;Han, In K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.4
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    • pp.565-572
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    • 1999
  • Two experiments were conducted to determine the effects of conditioning (conventional vs expander) corn- and sorghum-based diets on production traits for lactating sows and finishing pigs. In Exp. 1, one hundred sixty-eight sows (parity 1-4, PIC line C15) were fed the corn or sorghum grain diets as a meal, standard (steam) conditioned pellets, or expanded pellets to give a $2{\times}3$ factorial arrangement of treatments. Pellet durability index (PDD was similar for the sorghum- vs corn-based diets, but increased when diets were expanded pellets for both corn- and sorghum-based diets. The corn-based meal diet supported 3.3% greater litter weight gain than the sorghum-based meal diet (44.0 kg vs 42.8 kg). However, the advantage for the corn-based diet disappeared with expander processing (ie., sows fed the sorghum-based diet responded more to diets processed with the alternative processing technology). Sow weight change during lactation was similar (p>0.15) among treatments, although average daily feed intake tended to be greater (p<0.09) for the sows fed sorghum. For Exp. 2, a total of 71 barrows (average initial weight of 58.0 kg) were used in a growth assay to determine the effects of feeding com- and sorghum-based diets, as meal or pellets, after processing with a conventional steam conditioner or an expander (high-shear) conditioner. PDI was not different for the sorghum- vs corn-based diets, but increased from 84 to 95% with expander conditioning compared to conventional steam conditioning. Rate and efficiency of gain, and carcass leanness were similar for pigs fed sorghum and corn (p>0.15). Efficiency of gain was greater (p<0.04) for pigs fed the pelleted (356 g/kg) diets compared to those given the meal (348 g/kg) diets. However, efficiencies of gain were similar (p>0.11) for pigs fed the conventional- and expander-conditioned diets. Pelleting increased (p<0.01) the incidence and severity of stomach lesions regardless of grain type. In conclusion, corn-based meal diet resulted in a greater litter weight gain than the sorghum-based meal diet. However, that advantage disappeared when the diets were expanded and pelleted. Finishing pigs fed pelleted diets were more efficient than those fed meal diets.

APPLICATION AND EVALUATION OF THE GLEAMS MODEL TO A CATTLE GRAZING PASTURE FIELD IN NORTH ALABAMA

  • Kang, M. S.;P. prem, P.-Prem;Yoo, K. H.;Im, Sang-Jun
    • Water Engineering Research
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    • v.5 no.2
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    • pp.55-68
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    • 2004
  • The GLEAMS (Groundwater Loading Effects of Agricultural Management System, version 3.0) water quality model was used to predict hydrology and water quality and to evaluate the effects of soil types from a cattle-grazed pasture field of Bermuda-Rye grass rotation with poultry litter application as a fertilizer in North Alabama. The model was applied and evaluated by using four years (1999-2002) of field-measured data to compare the simulated results for the 2.71- ha Summerford watershed. $R^2$ values between observed and simulated runoff, sediment yields, TN, and TP were 0.91, 0.86, 0.95, and 0.69, respectively. EI (Efficiency Index) of these parameters were 0.86, 0.67, 0.70, and 0.48, respectively. The statistical parameters indicated that GLEAMS provided a reasonable estimation of the runoff, sediment yield, and nutrient losses at the studied watershed. The soil infiltration rates were compared with the rainfall events. Only high intensity rainfall events generated runoff from the watershed. The measured and predicted infiltration rates were higher during dry soil conditions than wet soil conditions. The ratio of runoff to precipitation was ranging from 2.2% to 8.8% with average of 4.3%. This shows that the project site had high infiltration and evapotranspiration which generated the low runoff. The ratio of runoff to precipitation according to soil types by the GLEAMS model appeared that Sa (Sequatchie fine sandy loam) soil type was higher and Wc (Waynesboro fine sandy loam, severely eroded rolling phase) soil type relatively lower than the weighted average of the soil types in the watershed. The model under-predicted runoff, sediment yields, TN, and TP in Wb (Waynesboro fine sandy loam, eroded undulating phase) and Wc soil types. General tendency of the predicted data was similar for all soil types. The model predicted the highest runoff in Sa soil type by 105% of the weighted average and the lowest runoff in Wc soil type by 87% of the weighted average

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Physicochemical Characteristics and Fatty Acid Composition of the Meat from Korean Native Black Pig with Different Slaughter Weight

  • Kim, Il-Suk;Jin, Sang-Keun;Jo, Cheo-Run;Lee, Moo-Ha;Jang, Ae-Ra
    • Preventive Nutrition and Food Science
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    • v.13 no.1
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    • pp.23-27
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    • 2008
  • The Korean native black pig (KNP) have several desirable meat qualities, which are highly demanded by Koreans in spite of its slow growth rate, low feed efficiency, and small litter size. The aim of this study was to evaluate meat quality and fatty acid composition of KNP at different slaughter weight in order to provide information to industry. Ninety female KNP of the same age (220 days) were divided into three groups by live body weights (30 pigs per each group); live weight of 50$\sim$59 kg (T1), 60$\sim$69 kg (T2) and 70$\sim$80 kg (T3), respectively. After slaughtering the longissimus dorsi muscle (LD) and backfat from each group were obtained after 24 hr chilling. Crude protein content and shear force of LD from T3 was higher than that from T1 and pH of LD was significantly lower in that from T1 than from T2 and T3. Color measurement indicated that LD of T2 group had a higher $L^*$-value and lower $a^*$-value than those of T1 and T3. Slaughter weight of KNP generally did not affect the fatty acid composition of LD and backfat but the content of oleic acid (C18:1) of T2 in LD was significantly higher than those of T1 and T3. The results may provide basic information to industry to promote the production and processing of KNP, and assist in meeting the Korean consumer's demand.

Quality Characteristics of Baechu Kimchi at Jangsu Area as Compared with Commercial Kimchi (장수지역 배추김치와 시판 배추김치의 품질 평가)

  • Lee, Young-Sook;Cha, Jin-A;Rho, Jeong-Ok
    • Journal of the East Asian Society of Dietary Life
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    • v.23 no.4
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    • pp.413-422
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    • 2013
  • This study investigates the kimchi from Jangsu area (JSK) and its comparison with commercial kimchi (CMK). We conducted a sensory evaluation for the pH, titratable acidity, salinity, hunter's color values and mechanical characteristics of kimchi. The pH of JSK is significantly higher than CMK throughout the fermentation (p<0.001). At 15 days, JSK reached the stage of optimal maturity for pH 4.23~4.55 and CMK showed pH 3.96~4.00 as conditions after the optimal maturity (p<0.001). From the results of acidity analyses, CMK also showed higher acidity values than JSK (p<0.001), indicating that the rate of fermentation progress was faster in CMK. Salinity of JSK was a litter higher than CMK1 and CMK2 (p<0.001) and JSK indicated significantly higher L, a, b values during fermentation (p<0.001). Moreover, the textural values were significantly higher in JSK2 and JSK3 retaining hardness of the tissues. In the sensory assessment, the color, flavor, crispness, taste, and overall preferences were higher in JSK3 at 15 days and 30 days than CMK. Therefore, it seems necessary for recipe developments of kimchi with local characteristics in order to industrialize kimchi by using alpine crops at Jangsu area.

Effects of controlled environmental changes on the mineralization of soil organic matter

  • Choi, In-Young;Nguyen, Hang Vo-Minh;Choi, Jung Hyun
    • Environmental Engineering Research
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    • v.22 no.4
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    • pp.347-355
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    • 2017
  • This study investigated how the combined changes in environmental conditions and nitrogen (N) deposition influence the mineralization processes and carbon (C) dynamics of wetland soil. For this objective, we conducted a growth chamber experiment to examine the effects of combined changes in environmental conditions and N deposition on the anaerobic decomposition of organic carbon and the emission of greenhouse gases from wetland soil. A chamber with elevated $CO_2$ and temperature showed almost twice the reduction of total decomposition rate compared to the chamber with ambient atmospheric conditions. In addition, $CO_2$ fluxes decreased during the incubation under the conditions of ambient $CO_2$ and temperature. The decrease in anaerobic microbial metabolism resulted from the presence of vegetation, which influences the litter quality of soils. This can be supported by the increase in C/N ratio over the experimental duration. Principle component analysis results demonstrated the opposite locations of loadings for the cases at the initial time and after three months of incubation, which indicates a reduction in the decomposition rate and an increasing C/N ratio during the incubation. From the distribution between the decomposition rate and gas fluxes, we concluded that anaerobic decomposition rates do not have a significantly positive relationship with the fluxes of greenhouse gas emissions from the soil.

Preliminary Phosphorous Removal Rate in a Natural-type Constructed Wetland for Stream Water Treatment (하천수정화 근자연형 인공습지의 초기 인 제거)

  • Yang, Hongmo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.5 no.6
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    • pp.30-36
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    • 2002
  • A 0.19 hectare natural-type wetland for stream water treatment demonstration was constructed and planted with cattails from April 2001 to May 2001. Part of its bottom surfaces adjacent to levees have a variety of slope of 1 : 4~1 : 15. Two small open water areas were installed, in which emergent plants could not grow. Removal of nutrients from stream waters was a major objective of the wetland. Waters of Sinyang Stream flowing into Kohung Estuarine Lake were pumped and funneled into the wetland. The lake had been formed by a salt marsh reclamation project and was located southern coastal region of Korean Peninsula. Volumes and water quality of inflow and outflow were analyzed from July 2001 through December 2001. Inflow and outflow averaged $120.4m^3/day$ and $112.1m^3/day$, respectively. Hydraulic retention time was about 3.1 days. Average total phosphorous concentration of influent and effluent was $0.19mg/{\ell}$ and $0.075mg/{\ell}$, respectively. Total phosphorous loading rate of inflow and outflow averaged $12.05mg\;m^{-2}\;day^{-1}$ and $4.44mg\;m^{-2}\;day^{-1}$, respectively. Average total phosphorous removal rate in the wetland was $7.61mg\;m^{-2}\;day^{-1}$. Seasonal changes of phosphorous retention rates were observed. The wetland acted as effective phosphorous sinks in the initial stage of the constructed wetland.

CONSIDERATIONS IN THE DEVELOPMENT OF FUTURE PIG BREEDING PROGRAM - REVIEW -

  • Haley, C.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.4 no.4
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    • pp.305-328
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    • 1991
  • Pig breeding programs have been very successful in the improvement of animals by the simple expedient of focusing on a few traits of economic importance, particularly growth efficiency and leanness. Further reductions in leanness may become more difficult to achieve, due to reduced genetic variation, and less desirable, due to adverse correlated effects on meat and eating quality. Best linear unbiased prediction (BLUP) of breeding values makes possible the incorporation of data from many sources and increases the value of including traits such as sow performance in the breeding objective. Advances in technology, such as electronic animal identification, electronic feeders, improved ultrasonic scanners and automated data capture at slaughter houses, increase the number of sources of information that can be included in breeding value predictions. Breeding program structures will evolve to reflect these changes and a common structure is likely to be several or many breeding farms genetically linked by A.i., with data collected on a number of traits from many sources and integrated into a single breeding value prediction using BLUP. Future developments will include the production of a porcine gene map which may make it possible to identify genes controlling economically valuable traits, such as those for litter size in the Meishan, and introgress them into nucleus populations. Genes identified from the gene map or from other sources will provide insight into the genetic basis of performance and may provide the raw material from which transgenic programs will channel additional genetic variance into nucleus populations undergoing selection.

Using a Choice Experiment to Measure the Non-market Value of Sea Water Quality with a Focus on the Incheon Special Area Management Plan (선택실험법을 이용한 해역수질 속성의 비시장적 가치 추정: 인천특별관리해역을 중심으로)

  • Jin, Se-Jun;Park, So-Yeon;Yoo, Seung-Hoon
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.24 no.4
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    • pp.451-458
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    • 2018
  • The coast of Incheon reaches Incheon itself, Gimpo, Siheung, and Ansan of Gyunggi-do. Because this area has been seriously polluted, the Ministry of Oceans and Fisheries has established the Incheon Special Area Management Plan (SAMP) to preserve sea water quality as a marine environment asset. However, there is concern that actions taken in this area may change the surrounding marine ecology, being effected by farms, via a river that flows from waste lands, abandoned fishing activities and fishing nets, etc. Given this background, this study estimates the value of SAMP sea water quality using a choice experiment (CE). A CE survey of 1,000 households was undertaken, investigating trade-offs involving price and four attributes for selecting a preferred alternative to obtain a marginal willingness to pay (MWTP) estimate for each attribute. The estimation results showed that MWTP for a 1 %p improvement in sea water quality, the diversity of fauna species, the diversity of flora species, and a 1 %p reduction in marine litter as a result of conserving Incheon coastal sea water quality are estimated to be KRW 75, 135, 309 and 72 per household per year, respectively. All estimation results were statistically significant at the 1 % level. These findings can provide policy makers with useful information for evaluating and planning marine environmental management policies.

Soil Respiration in Pinus rigida and Larix leptolepis Plantations (리기다소나무와 낙엽송(落葉松) 인공조림지내(人工造林地內) 토양발생(土壤發生) 이산화탄소(二酸化炭素)에 관한 연구(硏究))

  • Son, Yowhan;Kim, Hyun-Woo
    • Journal of Korean Society of Forest Science
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    • v.85 no.3
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    • pp.496-505
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    • 1996
  • Soil respiration was measured every two weeks from May through November 1995 using the soda lime method in 40-Year-old Pinus rigida and Larix leptolepis plantations on a similar soil in Yangpyeong, Kyonggi Province. Treatments included control and no-roots(plots trenched and root regrowth into plots prevented). Root respiration was evaluated by comparing no-roots sub-plots to control plots. Mean soil respiration showed highly significant species effects(p<0.01) and was highest at the Pinus rigida control plot($0.38g/m^2/hr$) and lowest at the Larix leptolepis no-roots plot($0.31g/m^2/hr$). High soil respiration in Pinus rigida may be related to aboveground litter production. The annual $CO_2$ fluxes ranged from 23 to 27t/ha/yr. We found significant correlations between temperatures(air : $R^2$=0.53, soil : $R^2$=0.55) and soil respiration(p<0.01), but no significant correlations between soil moisture and soil respiration(p>0.1). Root respiration was 3% of total soil respiration. We might underestimate rapt respiration because of shallow trenches and $CO_2$measurements right after trenching. Factors controlling soil respiration including belowground litterfall(especially fine roots) inputs, litter quality should be well understood to predict soil carbon fluxes and relative contributions to total soil respiration in forest ecosystems.

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