• Journal of Animal Science and Technology
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• v.45 no.2
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• pp.251-264
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• 2003

This study was conducted to make on-site survey on the output pattern and utilization situation of 19 by-products selected, to evaluate their nutritional characteristics, to find out a reliable index with which digestion of by-products can be predicted on the basis of chemical compositions analyzed and to diagnose the risk of using book values in the absence of the actual values analyzed for diet formulation. Production and utilization situations of by-products were quite various. Nutritionally, fruit processing by-products such as apple pomace (AP), pear pomace (PP), grape pomace (GP), and persimmon peel (PSP), and bakery by-products (BB) were classified as energy feeds. Soybean curd meal (SCM), animal by- products such as blood (BD), feather meal (FM) and poultry by-products (PB), and activated milk processing sludge (AMS) were classified as protein feeds. Soy hulls (SH), spent mushroom compost (SMC), barley malt hulls (BMH), waste paper (WP) and broiler litter (BL) were classified as roughage. Rumen contents (RC) and restaurant food waste (FW) were nutritionally analogous to complete diets for cattle and swine, respectively. Compared to soybean meal (SBM), BD and FM contained high (P<0.05) levels of amino acids and barley malt sprouts (BMS), AMS and FW contained low (P<0.05) levels of amino acids. Enzymatic (pepsin) digestibilities of proteinaceous feeds ranged between 99 and 66%. In vitro DM digestibility was high (P<0.05) in the order of FW, BB, AP, SH, PP, PSP, BMH, BMS, SCM, GP, RC, PB, BL, WP, SMC, AMS, FM and BD. In vitro DM digestibility had the highest correlation (r=0.68) with nonfibrous carbohydrate among chemical components. Differences between analyzed values of chemical components and book values were considerable. Caution is required in using book values when large amount of by-products are used in diets.

• Journal of Ecology and Environment
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• v.29 no.3
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• pp.237-245
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• 2006

Changes of the biomass, net primary productivity and P/B ratio during abandoned field succession after shifting cultivation were investigated in Pyoungchang, Gangwon-Do, Korea. Aboveground standing biomass of herb species showed the maximum value (3.8 ton/ha) in the 5 year old-field, and decreased thereafter. Litter dry weight was depicted as a parabola form showing the gradual increment during the first 50 years and slight decrease thereafter. Basal area tended to increase logarithmically during abandoned field succession. Tree density showed the gradual increment during the first 15 years and decreased thereafter by the self-thinning process. In the later successional stage (80 years old-field), the shoot density distribution of the tree species by DBH class showed the reverse J shaped curve and Quercus mongolica dominated. Total standing biomass increased slowly in the earlier successional stages and later successional stages, and increased rapidly during the mid-successional stages ($10{\sim}50$ years old-field). Total standing biomass in the 5, 10, 20, 50 and 80 years old-fields were estimated 5, 14, 75, 251 and 373 ton/ha, respectively. Annual net primary productivity were depicted as a parabola form showing the gradual increment during the first 35 years and declined thereafter. The increment rates of the annual net primary productivity in the earlier successional stages showed the higher value than mid-successional stages. The annual net primary productivities in the 5, 10, 20, 35, 50 and 80 years old-field were estimated 8.6, 9.3, 12.9, 15.1, 13.7 and 3.6 ton/ha/yr, respectively. The estimated P/B ratio tended to decrease exponentially during abandoned field succession. The estimated P/B ratio in the 5, 10, 20, 50 and 80 years old-field were 0.60, 0.39, 0.19, 0.06 and 0.01, respectively. These results were fairly in accordance with the bioenergetics model during the forest succession projected by Odum(1969).

• Korean Journal of Environment and Ecology
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• v.30 no.2
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• pp.243-252
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• 2016

Comparison of Organic carbon in the Quercus mongolica and Pinus densiflora forest at Mt. Gumgang were investigated. Carbon in above and below ground standing biomass, litter layer, and soil organic carbon were measured from September 2013 through August 2014. For the estimation of carbon cycling, soil respiration was measured. The amount of carbon allocated to above and below ground biomass in Q. mongolica and P. densiflora forest was 115.07/34.36, $28.77/8.59ton\;C\;ha^{-1}$, respectively. Amount of organic carbon in annual litterfall in Q. mongolica and P. densiflora forest was 4.89, $6.02ton\;C\;ha^{-1}$, respectively. Amount of organic carbon within 50cm soil depth was 132.78, $59.72ton\;C\;ha^{-1}$ $50cm-depth^{-1}$, respectively. Total amount of organic carbon in Q. mongolica and P. densiflora forest estimated to 281.52, $108.69ton\;C\;ha^{-1}$, respectively. Amount of organic carbon returned to the forest via litterfall in Q. mongolica and P. densiflora forest was 2.83, $2.20ton\;C\;ha^{-1}$, respectively. The amount of organic carbon absorbed from the atmosphere of this Q. mongolica and P. densiflora forest was 3.90, $0.81ton\;C\;ha^{-1}yr^{-1}$ respectively. Absorption of organic carbon in Q. mongolica forest was remarkably higher than P. densiflora forest.