• Title/Summary/Keyword: Constant frequency

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A Note on the Deveolopment of Tribolium castaneum (Coleoptera: Tenebrionidae) on Brown Rice Oryzae sativa L. (현미에서의 거짓쌀도둑, Tribilium castaneum(딱정발레목:거저리과)의 발육)

  • 전환구;홍영석;류문일
    • Korean journal of applied entomology
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    • v.30 no.2
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    • pp.103-137
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    • 1991
  • The developmental period(mean $\pm$ SE) of the red flour beetle, Tribolium castaneum was studied on brown rice at four constant temperature(25, 28, 34, $36^{\circ}C$ $\pm$ $0.5^{\circ}C$, RH 70%)conditions. Based on the results, the lower and the upper developmental threshold temperature for the beetle were also estimated. The duration of the egg stage was estimated to be 7.6 $\pm$ 0.25, 4.8 $\pm$ 0.10, 3.0 $\pm$ 0.03 and 2.5 $\pm$ 0.09 days at 25, 28, 34, $36^{\circ}C$, respectively. That of the larval stage was estimated to be 53.3 $\pm$ 1.49, 33.4 $\pm$ 0.57, 30.6 $\pm$ 0.70, 31.0 $\pm$ 1.18; that of the pupal stage to be 12.1 $\pm$ 0.17, 7.8 $\pm$ 0.09, 5.7 $\pm$ 0.09, 5.0 $\pm$ 0.07 ; that of the overall period which spans from eggs to the adult emergence to be 72.3 $\pm$ 1.67, 46.0 $\pm$ 0.55, 39.4 $\pm$ 0.64, 38.7 $\pm$ 1.15 days at 25, 28, 34, $36^{\circ}C$, respectively. The duration of the egg and the pupal stage were similar to those of the results reared on other diets such as wheat and maize. Fed on brown rice, however, the duration of the larval stage was significantly retarded than on wheat. The mortality of the beetle during ,development was higher on brown rice than on wheat reported, indicating that brown rice is a poor diet compared with wheat. The lower developmental threshold temperature was estimated to be $20.0^{\circ}C$ for all stages of the beetle. The upper one was estimated to be $40.2^{\circ}C$ for the overall stage. The modal value of the moulting times during the larval stage was 7. However, as temperature increased,.the frequency of the beetle that moulted more than 7 times became higher. The sex ratio of the beetle was not affected by temperature.

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Importance of Strain Improvement and Control of Fungal cells Morphology for Enhanced Production of Protein-bound Polysaccharides(β-D-glucan) in Suspended Cultures of Phellinus linteus Mycelia (Phellinus linteus의 균사체 액상배양에서 단백다당체(β-D-glucan)의 생산성 향상을 위한 균주 개량과 배양형태 조절의 중요성)

  • Shin, Woo-Shik;Kwon, Yong Jung;Jeong, Yong-Seob;Chun, Gie-Taek
    • Korean Chemical Engineering Research
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    • v.47 no.2
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    • pp.220-229
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    • 2009
  • Strain improvement and morphology investigation in bioreactor cultures were undertaken in suspended cultures of Phellinus linteus mycelia for mass production of protein-bound polysaccharides(soluble ${\beta}$-D-glucan), a powerful immuno-stimulating agent. Phellineus sp. screened for this research was identified as Phellinus linteues through ITS rDNA sequencing method and blast search, demonstrating 99.7% similarity to other Phellinus linteus strains. Intensive strain improvement program was carried out by obtaining large amounts of protoplasts for the isolation of single cell colonies. Rapid and large screening of high-yielding producers was possible because large numbers of protoplasts ($1{\times}10^5{\sim}10^6\;protoplasts/ml$) formed using the banding filtration method with the cell wall-disrupting enzymes could be regenerated in relatively high regeneration frequency($10^{-2}{\sim}10^{-3}$) in the newly developed regeneration medium. It was demonstrated that the strains showing high performances in the protoplast regeneration and solid growth medium were able to produce 5.8~6.4%(w/w) of ${\beta}$-D-glucan and 13~15 g/L of biomass in stable manners in suspended shake-flask cultures of P. linteus mycelia. In addition, cell mass increase was observed to be the most important in order to enhance ${\beta}$-D-glucan productivity during the course of strain improvement program, since the amount of ${\beta}$-D-glucan extracted from the cell wall of P. linteus mycelia was almost constant on the unit biomass basis. Therefore we fully investigated the fungal cell morphology, generally known as one of the key factors affecting cell growth extent in the bioreactor cultures of mycelial fungal cells. It was found that, in order to obtain as high cell mass as possible in the final production bioreactor cultures, the producing cells should be proliferated in condensed filamentous forms in the growth cultures, and optimum amounts of these filamentous cells should be transferred as active inoculums to the production bioreactor. In this case, ideal morphologies consisting of compacted pellets less than 0.5mm in diameter were successfully induced in the production cultures, resulting in shorter period of lag phase, 1.5 fold higher specific cell growth rate and 3.3 fold increase in the final biomass production as compared to the parallel bioreactor cultures of different morphological forms. It was concluded that not only the high-yielding but also the good morphological characteristics led to the significantly higher biomass production and ${\beta}$-D-glucan productivity in the final production cultures.

Comparison of Respiratory Mechanics and Gas Exchange Between Pressure-controlled and Volume-controlled Ventilation (압력조절환기법과 용적조절환기법의 호흡역학 몇 가스교환의 비교)

  • Jeong, Seong-Han;Choi, Won-Jun;Lee, Jung-A;Kim, Jin-A;Lee, Mun-Woo;Shin, Hyoung-Shik;Kim, Mi-Kyeong;Choe, Kang-Hyeon
    • Tuberculosis and Respiratory Diseases
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    • v.46 no.5
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    • pp.662-673
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    • 1999
  • Background : Pressure-controlled ventilation (PCV) is frequently used recently as the initial mode of mechanical ventilation in the patients with respiratory failure. Theoretically, because of its high initial inspiratory flow, pressure-controlled ventilation has lower peak inspiratory pressure and improved gas exchange than volume-controlled ventilation (VCV). But the data from previous studies showed controversial results about the gas exchange. Moreover, the comparison study between PCV and VCV with various inspiration : expiration time ratios (I : E ratios) is rare. So this study was performed to compare the respiratory mechanics and gas exchange between PCV and VCV with various I : E raitos. Methods : Nine patients receiving mechanical ventilation for respiratory failure were enrolled. They were ventilated by both PCV and VCV with various I : E ratios (1 : 2, 1 : 1.3 and 1.7 : 1). $FiO_2$, tidal volume, respiratory rate and external positive end-expiratory pressure (PEEP) were kept constant throughout the study. After 20 minutes of each ventilation mode, arterial blood gas, airway pressures, expired $CO_2$ were measured. Results : In both PCV and VCV, as the I : E ratio increased, the mean airway pressure was increased, and $PaCO_2$ and physiologic dead space fraction were decreased. But P(A-a)$O_2$ was not changed. In all three different I : E ratios, peak inspiratory pressure was lower during PCV, and mean airway pressure was higher during PCV. But $PaCO_2$ level, physiologic dead space fraction and P(A-a)$O_2$ were not different between PCV and VCV with three different I : E ratios. Conclusion : There was no difference in gas exchange between PCV and VCV under the same tidal volume, frequency and I : E ratio.

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A digital Audio Watermarking Algorithm using 2D Barcode (2차원 바코드를 이용한 오디오 워터마킹 알고리즘)

  • Bae, Kyoung-Yul
    • Journal of Intelligence and Information Systems
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    • v.17 no.2
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    • pp.97-107
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    • 2011
  • Nowadays there are a lot of issues about copyright infringement in the Internet world because the digital content on the network can be copied and delivered easily. Indeed the copied version has same quality with the original one. So, copyright owners and content provider want a powerful solution to protect their content. The popular one of the solutions was DRM (digital rights management) that is based on encryption technology and rights control. However, DRM-free service was launched after Steve Jobs who is CEO of Apple proposed a new music service paradigm without DRM, and the DRM is disappeared at the online music market. Even though the online music service decided to not equip the DRM solution, copyright owners and content providers are still searching a solution to protect their content. A solution to replace the DRM technology is digital audio watermarking technology which can embed copyright information into the music. In this paper, the author proposed a new audio watermarking algorithm with two approaches. First, the watermark information is generated by two dimensional barcode which has error correction code. So, the information can be recovered by itself if the errors fall into the range of the error tolerance. The other one is to use chirp sequence of CDMA (code division multiple access). These make the algorithm robust to the several malicious attacks. There are many 2D barcodes. Especially, QR code which is one of the matrix barcodes can express the information and the expression is freer than that of the other matrix barcodes. QR code has the square patterns with double at the three corners and these indicate the boundary of the symbol. This feature of the QR code is proper to express the watermark information. That is, because the QR code is 2D barcodes, nonlinear code and matrix code, it can be modulated to the spread spectrum and can be used for the watermarking algorithm. The proposed algorithm assigns the different spread spectrum sequences to the individual users respectively. In the case that the assigned code sequences are orthogonal, we can identify the watermark information of the individual user from an audio content. The algorithm used the Walsh code as an orthogonal code. The watermark information is rearranged to the 1D sequence from 2D barcode and modulated by the Walsh code. The modulated watermark information is embedded into the DCT (discrete cosine transform) domain of the original audio content. For the performance evaluation, I used 3 audio samples, "Amazing Grace", "Oh! Carol" and "Take me home country roads", The attacks for the robustness test were MP3 compression, echo attack, and sub woofer boost. The MP3 compression was performed by a tool of Cool Edit Pro 2.0. The specification of MP3 was CBR(Constant Bit Rate) 128kbps, 44,100Hz, and stereo. The echo attack had the echo with initial volume 70%, decay 75%, and delay 100msec. The sub woofer boost attack was a modification attack of low frequency part in the Fourier coefficients. The test results showed the proposed algorithm is robust to the attacks. In the MP3 attack, the strength of the watermark information is not affected, and then the watermark can be detected from all of the sample audios. In the sub woofer boost attack, the watermark was detected when the strength is 0.3. Also, in the case of echo attack, the watermark can be identified if the strength is greater and equal than 0.5.

The Weather Representativeness in Korea Established by the Information Theory (정보이론에 의한 한국의 일기대표성 설정)

  • Park, Hyun-Wook
    • Journal of the Korean association of regional geographers
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    • v.2 no.2
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    • pp.49-73
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    • 1996
  • This study produces quantitatively weather entropy and information ratio using information theory about frequency in the appearance of precipitation phenomenon and monthly change, and then applies them to observation of the change of their space scale by time. As a result of these, this study defines Pusan, Chongju and Kwangju's weather representativeness and then establishes the range of weather representativeness. Based on weather entropy (statistical parameter)-the amount of average weather information-and information ratio, we can define each area's weather representativeness, which can show us more constant form included topographical, geographical factors and season change. The data used for this study are the daily precipitotion and cloudiness during the recent five years($1990{\sim}1994$) at the 69 stations in Korea. It is divided into class of no precipitation, that of precipitation. The results of this study can be summarized as follows: (1) The four season's mean value of information ratio is the highest value. as 0.641, on the basis of Chongju. It is the lowest as 0.572, on the basis of Pusan. On a seasonal basis, the highest mean value of information rate is April's (spring) in Chongju, and the lowest is October's(fall) in Pusan. Accordingly weather representativeness has the highest in Chongju and the lowest in Pusan. (2) To synthesize information ratio of decaying tendancy and half-decay distance, Chonju's weather representativeness has the highest in April, July and October. And kwangju has the highest value in January and the lowest in April and July. Pusan's weather representativeness is not high, that of Pusan's October is the lowest in the year. (3) If we establish the weather representative character on the basis of Chongju-Pusan, the domain of Chongju area is larger than that of Pusan area in October, July and April in order. But Pusan's is larger than Chongju's in January. In the case of Chongju and Kwangju, the domain of Chongju area is larger than that of Kwangju in October, July and April in order, but it is less than that of Kwangju area in January. In the case of Kwangju-Pusan, the domain of Kwangju is larger than that of Pusan in October, July in order. But in April it is less than Pusan's.

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Rheological Properties of ${\beta}-Glucan$ Isolated from Non-waxy and Waxy Barley (메성 및 찰성보리 ${\beta}-Glucan$의 리올로지 특성)

  • Choi, Hee-Don;Park, Yong-Gon;Jang, Eun-Hee;Seog, Ho-Moon;Lee, Cherl-Ho
    • Korean Journal of Food Science and Technology
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    • v.32 no.3
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    • pp.590-597
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    • 2000
  • The rheological properties of ${\beta}-glucans$ isolated from non-waxy and waxy barley were investigated. ${\beta}-Glucan$ solutions showed pseudoplastic properties and their behaviors were explained by applying Power law model in the range of concentrations$(1{\sim}4%)$ and temperatures$(20{\sim}65^{\circ}C)$. The effects of temperature and concentration on the apparent viscosity at $700\;s^{-1}$ shear rate were examined by applying Arrhenius equation and power law equation, and their effect was more pronounced in waxy ${\beta}-glucan$ solutions. The activation energy for flow of ${\beta}-glucan$ solutions decreased with the increase of concentration, and the concentration-dependent constant A increased with the increase of temperature. The intrinsic viscosity of waxy ${\beta}-glucan$ was higher than that of non-waxy ${\beta}-glucan$. The transition from dilute to concentrate region occurred at a critical coil overlap parameter $C^*[{\eta}]=0.02.$ The slopes of non-waxy and waxy ${\beta}-glucan$ at $C[{\eta}] were similar, but the slope of waxy ${\beta}-glucan$ at $C[{\eta}]>C^*[{\eta}]$ was higher than that of non-waxy ${\beta}-glucan$. Dynamic viscoelasticity measurement showed that cross-over happened, and storage modulus was higher than loss modulus at frequency range above cross-over. ${\beta}-Glucan$ solutions formed weak gels after stored for 24 hr.

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Temperature-dependent Development and Its Model of the Greenbug, Schizaphis graminum (Rondani) (Homoptera: Aphididae) (보리두갈래진딧물 [Schizaphis graminum (Rondani)]의 온도발육과 발육모형)

  • Lee, Jang-Ho;Kim, Tae-Heung;Kim, Ji-Soo;Hwangn, Chang-Yeon;Lee, Sang-Guei
    • Korean journal of applied entomology
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    • v.46 no.2
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    • pp.213-219
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    • 2007
  • The development of Schizaphis graminum (Rondani) was studied at various constant temperatures ranging from 15 to $32.5^{\circ}C$, with $65{\pm}5%$ RH, and a photoperiod of 16L:8D. Mortality of the $1_{st}-2_{nd}\;and\;the\;3_{rd}-4_{th}$ stage nymphs were similar at most temperature ranges while at high temperature of $32.5^{\circ}C$, more $3_{rd}-4_{th}$ stage individuals died. The total developmental time ranged from 13.8 days at $15^{\circ}C$ to 4.9 days at $30.0^{\circ}C$ suggesting that the higher the temperature, the faster the development. However, at higher end temperature of $32.5^{\circ}C$ the development took 6.4 days. The lower developmental threshold temperature and effective accumulative temperatures for the total immature stage were $6.8^{\circ}C$ and 105.9 day-degrees, respectively and the nonlinear shape of temperature related development was well described by the modified Sharpe and DeMichele model. The normalized cumulative frequency distributions of developmental period for each life stage were fitted to the three-parameter Weibull function. The attendance of shortened developmental times was apparent with $1_{st}-2_{nd}\;nymph,\;3_{rd}-4_{th}$ nymph, and total nymph stages in descending order. The coefficient of determination $r^2$ ranged between 0.80 and 0.87.

Population Phenology and an Early Season Adult Emergence model of Pumpkin Fruit Fly, Bactrocera depressa (Diptera: Tephritidae) (호박과실파리 발생생태 및 계절초기 성충우화시기 예찰 모형)

  • Kang, Taek-Jun;Jeon, Heung-Yong;Kim, Hyeong-Hwan;Yang, Chang-Yeol;Kim, Dong-Soon
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.10 no.4
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    • pp.158-166
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    • 2008
  • The pumpkin fruit fly, Bactrocera depressa (Tephritidae: Diptera), is one of the most important pests in Cucurbitaceae plants. This study was conducted to investigate the basic ecology of B. depressa, and to develop a forecasting model for predicting the time of adult emergence in early season. In green pumpkin producing farms, the oviposition punctures caused by the oviposition of B. depressa occurred first between mid- and late July, peaked in late August, and then decreased in mid-September followed by disappearance of the symptoms in late September, during which oviposition activity of B. depressa is considered active. In full-ripened pumpkin producing farms, damaged fruits abruptly increased from early Auguest, because the decay of pumpkins caused by larval development began from that time. B. depressa produced a mean oviposition puncture of 2.2 per fruit and total 28.8-29.8 eggs per fruit. Adult emergence from overwintering pupae, which was monitored using a ground emergence trap, was first observed between mid- and late May, and peaked during late May to early June. The development times from overwintering pupae to adult emergence decreased with increasing temperature: 59.0 days at $15^{\circ}C$, 39.3 days at $20^{\circ}C$, 25.8 days at$25^{\circ}C$ and 21.4 days at $30^{\circ}C$. The pupae did not develop to adult at $35^{\circ}C$. The lower developmental threshold temperature was calculated as $6.8^{\circ}C$ by linear regression. The thermal constant was 482.3 degree-days. The non-linear model of Gaussian equation well explained the relationship between the development rate and temperature. The Weibull function provided a good fit for the distribution of development times of overwintering pupae. The predicted date of 50% adult emergence by a degree-day model showed one day deviation from the observed actual date. Also, the output estimated by rate summation model, which was consisted of the developmental model and the Weibull function, well pursued the actual pattern of cumulative frequency curve of B. depressa adult emergence. Consequently, it is expected that the present results could be used to establish the management strategy of B. depressa.

Typological Characteristics of Waterscape Elements from the Chapter 「Sancheon」 of the Volumes Gyeongsang-province in 『Sinjeung Donggukyeojiseungram』 (『신증동국여지승람』의 경상도편 「산천(山川)」 항목에 수록된 수경(水景) 요소의 특징)

  • Lim, Eui-Je;So, Hyun-Su
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.34 no.2
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    • pp.1-15
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    • 2016
  • This study aims at the consideration of the usages of traditional waterscape elements, which are difficult to define their concepts and their differences and it has been proceeded mainly with analysis of literature. It elicited various waterscape types by extracting the place names associated with the watersacpe elements from the chapter "Sancheon" of the volumes Gyeongsang-province in "Sinjeung Donggukyeojiseungram", which is a government-compiled geography book in the early period of Joseon Dynasty, and drew the features of each waterscape element by interpreting the dictionary definition and the original text and studying the similar examples. The results of study are drawn as follows. 1. The chapter "Sancheon" includes 22 types of waterscape elements and they are classified by means of locations and water-flow forms: River Landscape, Lake & Pond Landscape, Coast landscape. 2. River landscape maintaining constant natural water-flow constitutes the linear type, related to the class of stream, which includes 'Su(water)', 'Gang(river)', 'Cheon(stream)' and 'Gye(brook)' and the dotty type, created by the nature of trenched meander rivers, which includes 'Tan(beach)', 'Roe(rapids)', 'Pok(waterfall)' and 'Jeo(sandbank)'. 3. Lake & Pond Landscape forming water collected in a certain area constitutes 'Ho(lake)', which is a broad and calm spot created around mid and down stream of river, 'Yeon(pool)', 'Dam(pond)', 'Chu(small pond)', which are naturally created on the water path around mid and down stream of river, 'Ji(pond)', 'Dang(pond)', 'Taek(swamp)', which is collected on a flatland and 'Cheon(spring)', 'Jeong(spring)' which means gushing out naturally. 4. Coast Landscape includes 'Ryang', 'Hang', which are the space between land and an island or islands, 'Got(headland)' which sticks out from the coast into the sea, 'Jeong(sandbank)' which forms sandy beaches and 'Do' which shows high appearance frequency by reflecting the geographical importance of islands. This study comprehended the diversity of traditional waterscape elements and drew the fact that they are the concept reflecting the differentiated locational, scenic and functional features. That way, it understood the aesthetic sense on nature, which ancestors had formed with the interests in natural landscape and the keen observation on it, became the basic idea elucidating the characteristic on Korean traditional gardens, which minimize the artificiality and make nature the subject.

The Influence of organic Matter on Soil Aggregation in Forest Soils (삼림토양내(森林土壤內)의 유기물함량(有機物含量)이 토양입단화(土壤粒團化)에 미치는 영향(影響))

  • Park, Gwan Soo;Lee, Soo Wook
    • Journal of Korean Society of Forest Science
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    • v.79 no.4
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    • pp.367-375
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    • 1990
  • In order to determine the effects of bedrock, organic matter, calcium and iron oxide on the soil aggregation, this research has performed with soils from bedrock regions of Limestone, Granite and Granite gneiss. This research was also to estimate how organic matter, calcium and iron oxide influence on soil aggregation under different forest conditions in various bedrock regions. And it also had a purpose to rate physical factors relevant to soil aggregation, their characteristics and aggregate diameter which closely relates to stabilities in the process of soil erosion. The following conclusions have been drawn in response to the overall research objectives. The rates of the soil aggregation on different bedrock regions were 21% in Limestone bedrock, 19.8% in Granite bedrock and 9.9% in Granite gneiss bedrock. A main factor in soil aggregation was the orgainc matter content in soils and the rate of soil aggregation increased in the constant proportion with the organic matter content. The relation could be formulated into Y=4.31X-4.37(Y : aggregation ratio X : organic matter content). The soil aggregation ratio under the deciduous forests eras higher than that under the coniferous forests. It was considered that this resulted from differences in organic matter content. Soil aggregates with larger diameter than 0.5mm were found more in Limestone bedrock than other smaller size soil aggregates of 0.25mm diameter were more distributed in Granite gneiss bedrock. Granite bedrock region had normal distribution in soil aggregate sizes with the highest frequency of 0.5mm diameter. Calcium and iron oxides had only partial influences on the soil aggregation in some specific conditions. But in Limestone bedrock region calcium influenced on the soil aggregation with the organic matter content.

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