The magnetogram inversion technique (MIT) has been demonstrated as a powerful $quot;remote sensing tool$quot; in estimating ionospheric quantities, such as ionospheric current, field-aligned current, electric potential and Joule heating rate etc. Furthermore it is now possible to infer instantaneous patterns of such global distributions with a high time resolution (say, 5 min) through the numerical method. However, the electric potential distribution estimated from the MIT is very sensitive to the choice of ionospheric conductivity models. It is a serious drawback of the method, since the electric potential over the polar region is a very important quantity reflecting the efficiency of the solar wind-magnetosphere coupling. Thus a realistic conductivity distribution over the entire polar ionosphere is acute. In this paper, we introduce a general concept of ionospheric electric conductivity along with several methods of estimating it.

This paper reports on the investigation of the distributions of sediments and heavy metals in Sooyoung River and its mouth, carried out during the period from July 1990 and August 1991. Since the samples were saline, water analysis was performed by the method of alkaline KMnO₄ and sediment analysis by acidic KMnO₄. Mercury was digested with both nitric and sulfuric acids, and then determined by dithizone CCl4 method. Cadmium, Zinc, Copper, Lead and Chronium were determined by atomic absorption spectroscopy after aliquots of samples were digested with nitric acid and hydrogen peroxide. Mineral components of sediments were identified by XRD and microscopic analysis. The result are as follows : 1. The ranges of COD of water and sediments were 10.6-54.6ppm and 63-26000ppm respectively. 2. The ranges of concentrations of Cadmium, Lead, Copper and Zinc for water were 0.002 -0.024ppm, 0. 013-0.060ppm, 0.013-0.736ppm, 0.003-0.012ppm, respectively. 3. The ranges of concentration of Mercury, Cadmium, Lead, Copper, Zinc and Chromium for sediments were N.D - 0.09ppm, 0 .1-2.07ppm, 0.32-5 2.35 ppm, 1.04 - 20.67 ppm, 7.1-52.50 ppm and 0.23-5.22 ppm, respectively. 4. The mineral components of the sediments were mainly quartz and feldspar.

혼파된 영년채초지에서의 예취빈도와 질소시비가 뿌리의 수량과 심층분포에 미치는 영향에 대하여 연구된 결과는 다음과 같다. 1. 조사된 식생구조에서의 뿌리의 분포는 모든 처리구에서 상층 20cm까지에 그 대부분이 존재하였다. 2. 뿌리의 양은 우점종에 관계없이 모두 높았지만 Arrhenatherum elatius 우점초지에서 가장 낮았고 Alopecurns pratensis우점초지에서 가장 높았다. 3.뿌리의 양은 예취빈도간에는 그 차이가 없었으나 적당한

관광개발에 따른 심한 환경변화가 예상되는 지리산 국립 공원의 어족자원을 보호하기 위한 기초자료를 얻고자 이 지역의 어류분포상을 조사하였다. 국립공원내 하천에서 확인된 어종은 잉어과, 퉁가리과 및 농어과가 포함된 3과에 속하는 4종이었다. 우점종은 갈겨니였으나 이미 보고된 자료보다는 약간 감소추세을 보이고 있다. 따라서 이 지역에 대한 각별한 보호와 분별있는 관광개발이 요망된다.

The depth and spread of root systems and the density of root branching affect the success and survival of plants subjected to drought. The type and size of root systems are controlled by heredity and soil conditions. There are also important interaction between roots and shoots; roots are dependent on shoots for carbohydrates, growth regulators, and certain vitamins, and shoots are dependent on roots for water, minerals, and certain growth regulators. Pinus thunbergii Parlatore had most of roots in the top 20cm of soil, and had little short of roots in the less than 80cm of soil. Average of root density was in the upper soil(0~20cm). Root density of Pinus thunbergii Parlatore was similar to that of Cryptomeria japonica. There is no saying that Pinus thunbergii Parlatore has an advantage over Cryptomeria japonica in the drought. This data will be used to the root density values in the simulation model of black pine stands.

헝가리 국립자연사박물관에 소장된 북한산 노린재표본을 확인해본결과 11과 48속 64종이 분류 동정 되었으며, 그 중에서 Leptoterna dolavorata(머리무늬장님노린재), Mecomma amlulans(백두흰점장님노린재), Campylomma annulicornis(검은촉각장님노린재)등 3동은 우리나라 미기록종이었다.

지난 70년 이래 헝가리자연사전문관의 북한지역 탐사를 통해 채집보관된 표본을 대상으로 검경한 결과 북한산 잎말이나방과 총 26종이 분류.동정되었다. 그중 갈색잎말이, 솔잎말이, 매실애기잎말이, 팥나방, 흰갈퀴잎말이등 5종을 제외한 21종은 북한지역에서는 처음으로 보고되는 종들이다.

Marohae Bay in the South Coast of Korea, which is composed of complex coasts and many islands of various size, was surveyed to examine the source and transportation of sediments. The surface sediments with consist of gravelly sand, silt, sightly gravelly muddy silt, sand, clayey sand could be divided into three fades a and, silt and gravel facies. Micro-organisms of warm water included Dictyocha oceanica of nannoplankton were occurred in surface sediments. On the basis of study results, it is assumed that the study area shows the characteristic depositional environment which fine sediments could be transported from low latitude by Kuroshio current.

This research aim to geochemical study and the abundance of the trace elements of gneisses distributed in the western region of Mt.Chirisan. Analyzing the trace elements Gke Cu, Cr, Pb, Ni, Co, Mn, Li, Zn for 205 rock samples, and average abundance, range of abundance, frequency of each element were examined. Migmatitic gneiss, metatectic gneiss, porphyroblastic gneiss, granitic gneiss of studied area are lots of average abundance of Cu, Cr, Ni, Co and avidly scattered irregularly frequencies distribution. Also these are very similar to those of shales, therefore, considered to be sedimentary origin. Leucocratic granitic gneiss have lower average abundances in all eight trace elements than those of shales and have similar trace element abundances to those of Namwon granites, therefore, this is igneous origin.

Intermediated-basic plutons in Jirisan area consist of Pre-Cambrian anorthosite and gabbro, and Jurassic diorite and syenite. Many of bodies of massif type anorthosite are multi-intrusion and intruded by gabbroic rock which compose gabbro, norite, troctolite and leucogabbro. Younger intermediated plutons intruded into older basic plutons and formed contaminated zone at margin of basic plutons. Plagioclase of these plutons is of labradorite(An_(56∼60)) to bytownite(An_(60∼86)) in anorthosite, andesine(An_(35∼49)) in diorite and andesine(An_(30∼41)) in syenite: Continuous variation of anorthosite amount in these plutons suggest that basic and intermediated plutons are a series of differentiated product from two co-magma. Pyroxenes are correspond to salite of CPX, and hypersthene of OPX, and show continuous variation of component diopside to hedenbergite in salite and enstatite to ferrosilite in hypersthene. Variation of these component indicate these plutons are also a series of differentiated product from co-magma. Two synchronous plutons plotted on Harker diagram and AMF diagram show mostly similar trend to Daly's values and calcalkali rock series. Accoding to REE(La/Yb)_(cn) and Eu/Sm, it is concluded that intermediated-basic pluton having enriched LREE than HREE and emplaced by the tectonic setting in continent and/or continental margin.