• Journal of Ecology and Environment
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• v.43 no.1
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• pp.43-60
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• 2019

Background: Tropical montane forests played an important role in the provision of ecosystem services. The intense degradation and deforestation for the need of agricultural land expansion result in a significant decline of forest cover. However, the expansion of agricultural land did not completely destruct natural forests. There remain forests inaccessible for agricultural and grazing purpose. Studies on these forests remained scant, motivating to investigate biomass and soil carbon stocks. Data of biomass and soils were collected in 80 quadrats ($400m^2$) systematically in 5 forests. Biomass and disturbance gradients were determined using allometric equation and disturbance index, respectively. The regression modeling is employed to explore the spatial distribution of carbon stock along disturbance and environmental gradients. Correlation analysis is also employed to identify the relation between site factors and carbon stocks. Results: The result revealed that a total of 1655 individuals with a diameter of ${\geq}5cm$, representing 38 species, were measured in 5 forests. The mean aboveground biomass carbon stocks (AGB CS) and soil organic carbon (SOC) stocks at 5 forests were $191.6{\pm}19.7$ and $149.32{\pm}6.8Mg\;C\;ha^{-1}$, respectively. The AGB CS exhibited significant (P < 0.05) positive correlation with SOC and total nitrogen (TN) stocks, reflecting that biomass seems to be a general predictor of SOCs. AGB CS between highly and least-disturbed forests was significantly different (P < 0.05). This disturbance level equates to a decrease in AGB CS of 36.8% in the highly disturbed compared with the least-disturbed forest. In all forests, dominant species sequestrated more than 58% of carbon. The AGB CS in response to elevation and disturbance index and SOC stocks in response to soil pH attained unimodal pattern. The stand structures, such as canopy cover and basal area, had significant positive relation with AGB CS. Conclusions: Study results confirmed that carbon stocks of studied forests were comparable to carbon stocks of protected forests. The biotic, edaphic, topographic, and disturbance factors played a significant variation in carbon stocks of forests. Further study should be conducted to quantify carbon stocks of herbaceous, litter, and soil microbes to account the role of the whole forest ecosystem.

• Journal of Mushroom
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• v.14 no.2
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• pp.51-58
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• 2016

Basidiomycetous fungi are one of the most potent biodegraders because many of its species grow on dead wood or litter, in environments rich in lignocellulose. For the degradation of lignocellulose, basidiomycetes utilize their lignocellulytic enzymes, which typically include laccase (EC 1.10.3.2), lignin peroxidase (EC 1.11.1.14), xylanase (EC 3.2.1.8), and cellulase (EC 3.2.1.4). In recent years, the practical applications of basidiomycetes have ranged from the textile to the pulp and paper industries, and from food applications to bioremediation processes and industrial enzymatic saccharification of biomass. Recently, spent mushroom substrates of edible mushrooms have been used as sources of bulk enzymes to decolorize synthetic dyes in textile wastewater. In this review, the occurrence, mode of action, general properties, and production of lignocellulytic enzymes from mushroom species will be discussed. We will also discuss the potential applications of these enzymes.

• Journal of Plant Biology
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• v.32 no.2
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• pp.109-119
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• 1989

Adhatoda vasica Nees is a shrubby component of tropical and subtropical vegetation in Pakistan. t harbours relatively few unhealthy associated species in and around its thickets. Aqueous extracts, rain leachates, litter from shoots and soil underneath it invariably reduced germination, early growth, biomass, moisture and chlorophyll contents of Pennisetum americanum, Setaria italica, Zea mays, Brassica campestris and Triticum vulgare in different laboratory expreiments. chromatographic analysis revealed the presence of caffeic, ferulic, vanillic, p-coumaric, p-OH-benzoic, and tannic acids in aqueous extracts. The phytotoxicity was related to the test species used, part assayed and parameter measured. It is suggested that the preclusion of the associated species and the dominance of A. vasica is primarily due to allelopathy. Negative grazing also provides better chances for its establishment.

• Journal of Korean Society of Forest Science
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• v.85 no.4
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• pp.656-666
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• 1996

Aspen demand has increased recently in the Great Lakes region in the United States. Since aspen has moved into the region in late 1800's, its growing stock has increased so as to change forestry industry of the Lake States. Intensive timber harvesting and biomass removal may cause nutrient depletion, especially on nutrient-poor sites. Forest nutrients and nutrient cycling were investigated in aspen stands of 7-10, 27-33, and 41-42 year-old growing on sandy soils in Minnesota. Nutrients added to the aspen stands by atmospheric deposition and soil weathering were efficiently absorbed and stored in the tree biomass. Aboveground biomass increased from $24.4t{\cdot}ha^{-1}$ at young stands to $139.2t{\cdot}ha^{-1}$ at mature stands. Nutrients accumulated in the tree biomass showed same magnitude of difference. Nutrients added to the site through atmospheric deposition were in the order of Ca, N, K, Mg, and P. Annual litterfall was greater in older stands. However, the amount of nutrients returned by litterfall was not significantly different among stand ages due to the greater nutrient contents in the litterfall of young stands. Litter decomposition and nutrient release rates were greater at young stands than at older stands. Likewise, nutrient availability was higher in young aspen stands and became lower as the stands grew older. Nutrient leaching loss was minimal at all stand ages. Soil N mineralization was greater at young stands than at older stands. Nutrient cycling process was facilitated in young aspen stands with an increased level of available nutrients, Based on the estimations of nutrient balance and nutrient removal by harvesting, Ca was the most critical element which was likely to be depleted if aspen stands are intensively harvested with short rotations.

• The Korean Journal of Ecology
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• v.19 no.6
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• pp.529-541
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• 1996

During the period of December 1992 (winter-spring) and from February 1995 (winter-spring), the leaf processing rates of oak (Quercus serrata) and tulip (Liriodendron tulipifera) tree was investigated in the headwater streams in southeastern part of Korea in conjunction with the distribution pattern of macroinvertebrate fauna. Using two types of bags ($10\times30cm$ with 5 g of dry leaves; open bag with holes, closed bag without holes), decomposition rates of oak and tulip tree by shredder and/or microbiota at a reatively undisturbed 2nd-order stream were compared, Regardless of leaf type, leaves in the open bage decomposed slightly faster than those in the closed bags. In the 1992 experiment, osk leaves decomposed much slower than tulip leaves (after 138 degree days, osk : closed, 0.006% loss/day ; open, 0.008 ; tulip: closed, 0.021 ; open, 0.023; n=2). The of the first experiment using oak leaves in 1995 were similar to those of the first experiment (after 151 degree days, oak: closed, 0.005% loss / day; open, 0.006; n=6). Over 50% of invertebrates from 122 leaf pack samples collected from 12 streams during the winter period of 1994 were identified as shredders (shredder, 56.2; collector, 32.7; scraper, 8.65; predator, 2.45%). Among shredders, Gammarus sp. and Tipula sp. were dominant species in terms of number and biomass (8.2 ind./g, 1.0 ind./g AFDW of leaves). Among many physico-chemical parameters, the width of stream channel was found to be the most influential factor in the distribution of Gammarus and Tipula (Gammarus: r=-0.34, P<0.001;Tipula:r=0.40, P<0.001). Considering the fact that oak is one the dominant riparian vegetation in the southeastern part of korea, the patterns of oak processing and shredder distribution shown in theis study may well represent some of the important characteristics of headwater steams in southeastern Korea.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.9
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• pp.1228-1234
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• 2000

The reported study was conducted on range managed Malpura ewes that were non-breeding empty, were at an advanced stage of pregnancy, and were in early lactation, under a protocol of free grazing with concentrate supplementation at 1.00, 1.25 and 1.50% of their body weight to assess their plane of nutrition and nutrient intake. The biomass yield of pasture plots was 1689, 1820 and 2912 kg/ha in pregnancy, lactation and empty phases, respectively. In addition to natural shrubs and forbs, Cenchrus ciliaris (36.4%) and dead litter (31.6%) were the major component of pasture vegetation during pregnancy. The dead litter disappeared during the lactation and empty phase with a concomitant increase in distribution of Cenchrus ciliaris to 73.0 and 87.2% respectively. The daily dry matter consumption from supplemental concentrate and free grazing was 70.1, 57.3 and 63.5 g/kg $W^{0.75}/d$ with concentrate to roughage ratio of 40:60, 47:53 and 33:67 in pregnancy, lactation and empty phases respectively. Digestibility of DM and OM were similar in the three phases while CP digestibility was higher (p<0.0l) during lactation than other two phases. Digestibility of NDF, ADF and cellulose were higher (p<0.0l) in empty than pregnancy and lactation, while hemicellulose digestibility was similar in lactation and empty and lower in pregnancy phase. The ewes in ~hases of pregnancy, lactation and empty consumed 7.1, 7.7 and 6.1 g DCP and 197.2, 214.6 and 232.5 kcal DE/kg $W^{0.75}/d$ respectively. It is concluded that ewes maintained on semi-arid Cenchrus dominated pasture with concentrate supplementation during pregnancy, lactation and empty phases consumed 45.2, 45.1 and 35.2 g DCP/Mcal ME respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.2
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• pp.280-289
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• 2015

Anaerobic digestion is an efficient and renewable energy technology that can produce biogas from a variety of biomasses such as animal manure, food waste and plant residues. In developing countries this technology is widely used for the production of biogas using local biomasses, but there is little information about the value of these biomasses for energy production. This study was therefore carried out with the objective of estimating the biogas production potential of typical Vietnamese biomasses such as animal manure, slaughterhouse waste and plant residues, and developing a model that relates methane ($CH_4$) production to the chemical characteristics of the biomass. The biochemical methane potential (BMP) and biomass characteristics were measured. Results showed that piglet manure produced the highest $CH_4$ yield of 443 normal litter (NL) $CH_4kg^{-1}$ volatile solids (VS) compared to 222 from cows, 177 from sows, 172 from rabbits, 169 from goats and 153 from buffaloes. Methane production from duckweed (Spirodela polyrrhiza) was higher than from lawn grass and water spinach at 340, 220, and 110.6 NL $CH_4kg^{-1}$ VS, respectively. The BMP experiment also demonstrated that the $CH_4$ production was inhibited with chicken manure, slaughterhouse waste, cassava residue and shoe-making waste. Statistical analysis showed that lipid and lignin are the most significant predictors of BMP. The model was developed from knowledge that the BMP was related to biomass content of lipid, lignin and protein from manure and plant residues as a percentage of VS with coefficient of determination (R-square) at 0.95.This model was applied to calculate the $CH_4$ yield for a household with 17 fattening pigs in the highlands and lowlands of northern Vietnam.

• The Korean Journal of Ecology
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• v.5 no.4
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• pp.204-210
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• 1982

Comparative study of the biomass productioin and the cyclings of nitrogen, phosphorus and potassium was carried out on the east and the northwest facing slope in the montane grassland of Mt. Soback. The maximum productin during the growing season in the east and the northwest slope were 1, 150g/m2.yr, and 755g/m2.yr. in the August, respectively. The positive correlation was appearent between biomass production and A-layer depth of the soil and the correlation coefficient (r=.964) was very significant at 1% level. In the above ground materials, the nutrients contents were high at the early of the growing season but decreased gradually. In roots, however, there are no significant trend throughout the growing season. Total amounts of minerals uptaken by plants during the growing season in the east and the northwest site were 18.20 and 10.66g/m2.yr for N, 0.06 and 0.03g/m2.yr for P, 0.23 and 0.11g/m2.yr for K, respectively. the minerals returned to the soil by litter decomposition and roots decay in the east and the northwest site were 16.19 and 9.62g/m2.yr for N, 0.046 and 0.021g/m2.yr for P, 0.211 and 0.099g/m2.yr for K, respectively. The turnover the rate (absorbed/returned) of the nutrients in the east and the northwest site were 1.13 and 1.14 for N, 1.30 and 1.43 for P, 1.09 and 1.11 for K, and the absorption rates of minerals were 0.39 and 0.29% for N, 3.16 and 1.88% for P, 0.91 and 0.57% for K, respectively.

• Korean Journal of Environmental Biology
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• v.22 no.3
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• pp.381-386
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• 2004

To develop accurate and predictive global carbon cycle models, it is important to understand the change of accumulated carbon for many ecosystems according to successional stage. In this study, I measured total biomass, litter and soil organic matter contents through an aerial photo and field observation. As a result, accumulated organic matter contents per unit area (kg $m^{-2})$ of three communities composed at grassland were 7.00 kg $m^{-2}$, in Solidago altissima community, 9.18 kg $m^{-2}$, in Imperata cylindrica community, and 12.68 kg $m^{-2}$, in Miscanthus sinensis community, respectively. Accumulated total organic matter contents was high in Miscanthus sinensis community at later succession stage but soil carbon was low. In Miscanthus sinensis community, highly accumulated organic matter contents was resulted from increasing of biomass comparison with that of the other two communities. The pattern of accumulated organic matter contents was changed by changing of the dominant community due to progressing in succession. The accumulated carbon in temperate grassland will be increased with progressing in succession.

• The Korean Journal of Ecology
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• v.16 no.2
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• pp.229-238
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• 1993

Ecological role of earthworms in red pine forest was investigated with emphasis on the population size, cast production and changes of physicoKDICical properties of soil by earthworm's activities. The density of earthworms was 62.8/m2 in August, 1992. Average biomass of earthworms was 16.3 g/m2. N and P concentrations in the tissue of earthworms were 28.5 mgN/g and 0.5 mgP/g, respectively. Cast production continued from April to November, with a peak in August. Annual production of earthworm casts was 5,379 g/m2. Bulk density of surface soil decreased due to the earthworm's cast-forming activity. Clay fraction in surface soil increased by addition of casts. Soil KDICical properties were significantly different between the surface soil and the earthworm casts. The amounts of organic matter, N, P, K, Ca and Mg added to the soil via earthworm casts during one year were 9.3t/ha, 11.29 kg/ha, 0.78 kg/ha, 12.36 kg/ha, 140.29 kg/ha and 20.96 kg/ha, respectively. Earthworms can feed on waxy and resinous litter when it became palatable by decomposing processes.