• Title/Summary/Keyword: Ultramafic soils

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Toxic Effects of Serpentine Soils on Plant Growth

  • Kim, Jeong-Myeong;Shim, Jae-Kuk
    • Journal of Ecology and Environment
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    • v.31 no.4
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    • pp.327-331
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    • 2008
  • Serpentine soils are distributed in a small area in Korea, and generally exhibit high contents of Ni, Cr, Fe, Mn, Co and Mg. We investigated the growth of woody plants and herbs in the Andong serpentine area, Korea. Pinus densiflora and P. rigida growing on serpentine soils have high contents of Fe, Mg, Ni and Co, with contents approximately twice as high as those of non-serpentine plants. Tree species on serpentine soil also had lower ratios of tree height/DBH than trees in a control area. In greenhouse culture experiments on two bodenvag herb species, Setaria viridis and Cymbopogon tortilis, the biomass of the plants was significantly affected by soil type but not by seed origins. After 66 days, the growth of S. viridis and C. tortilis seedlings was significantly inhibited in serpentine soil, and the dry weight of each species showed significant negative correlations with soil heavy metal contents (Ni, Co and Cr). These results suggest that the growth of plants was inhibited by properties of the serpentine soil, and in particular, their high heavy metal concentration, which induced dwarfing in woody plants and reduction of total plant biomass in herbs.

Composition, Ecology and Conservation of the Andong Serpentine Flora, South Korea (안동 사문암 지역의 식물상과 생태와 보전)

  • Park, Jeong Seok;Kim, Yun Ha;Nam, Hee Jung;Eom, Byeongcheol;Lee, Gyeong-Yeon;Kim, Jong Won
    • Korean Journal of Plant Resources
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    • v.35 no.4
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    • pp.515-540
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    • 2022
  • The ultramafic serpentine area, the small size of 3 km2, remains in Andong, South Korea. We researched the ecological flora and its structure through the 12 times field investigations from 2013 till 2018. A total of 527 taxa including the previously recorded species-list was analyzed. Among them, 331 taxa were filed up as a real flora of the serpentine area. On the vegetation land-cover map describing a characteristic aspect of species distribution, a matrix of the sparse forest by Pinus densiflora and the grassland patches were the main landscape. The study area was acknowledged as a home for the ethnobotanical species and grassland components, and clearly distinctive from the non-serpentine area. The original habitat was too deteriorated by introducing the non-site soils and exotic plants. Conclusionally a designation of a protected area and the long-term ecological monitoring were requested.

Mineralogical Characteristics of Naturally Occurring Asbestos (NOA) at Daero-ri, Seosan, Chungnam, Korea (충남 서산 대로리 일대 자연발생석면의 광물학적 특성)

  • Jung, Haemin;Shin, Joodo;Kim, Yumi;Park, Jaebong;Roh, Yul
    • Economic and Environmental Geology
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    • v.47 no.5
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    • pp.467-477
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    • 2014
  • Naturally occurring asbestos (NOA) occurs in rocks and soils as a result of natural weathering and human activities. The asbestos have been associated with ultramafic and mafic rocks, and carbonate rock. The previous studies on NOA were mainly limited to ultramafic and mafic rock-hosted asbestos in Korea. But, studies on carbonatehosted asbestos are relatively rare. Therefore, the purposes of this study were to investigate mineralogical characteristics of carbonate-hosted and metapelite-hosted NOA and to examine genesis of NOA occurred in the both rocks. The study area was Daerori, Seosan, Chungnam Province, Korea. The major rock formation consisted of limestone and schist which have been known to contain asbestos. Sampling was performed at outcrop which contained carbonate rock showing acicular asbestos crystals as well as pegmatitic intrusion that contacted with carbonate rock. PLM, XRD, EPMA, and EDS analyses were used to characterize mineral assemblages, mineralogical characteristics, and crystal habits of amphiboles and other minerals. BSEM images were also used to examine the genesis of asbestos minerals. The amphibole group was observed in all of the carbonate rocks, and actinolite and tremolite were identified in all rocks. These mineral habits were mainly micro-acicular crystals or secondary asbestiform minerals on the surface of non-asbestiform minerals appearing split end of columnar crystals produced by weathering. BSEM images showed residual textures of samples. The residual textures of carbonate rocks showed dolomite-tremolite-diopside mineral assemblages that formed during prograde metasomatism stage. Some carbonate rock also showed diopside-tremolite-talc mineral assemblages which were formed during retrograde metasomatism stage, as the residual textures. In result the presence of asbestos actinolite-tremolite in the carbonate rocks were confirmed in the areas where actinolite-tremolite asbestos was influenced by low temperature hydrothermal solution during metasomatism stage. These asbestos minerals showed the acicular asbestiform minerals, but even non-asbestiform minerals, a bundle or columnar shape, could transform to asbestiform minerals as potential NOA by weathering because the end of columnar shape of non-asbestiform minerals appeared as multiple acicular shaped fibers.

Interpretation of the Manufacturing Characteristics and the Mineral and Chemical Composition of Neolithic Pottery Excavated from the Jungsandong Site, Yeongjong Island, South Korea (영종도 중산동 신석기시대 토기의 광물 및 화학조성과 제작특성 해석)

  • Lee, Chan Hee;Kim, Ran Hee;Shin, Sook Chung
    • Korean Journal of Heritage: History & Science
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    • v.51 no.1
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    • pp.4-31
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    • 2018
  • The Neolithic pottery excavated from the Jungsandong site has been classified into four types of pottery (I: feldspar type, II: mica type, III: talc type and IV: asbestos type) according to their mineral composition. These four types of potteries generally appear to have undergone incomplete firing, while the level of oxidation in the type I pottery objects, which have a relatively higher clay content, was found to be particularly low. The type III objects, which have a high talc content, are judged to have been somewhat slow in removing carbon because they contain saponite belonging to the smectite group. Of the four types of pottery, type IV showed the highest redness and the most uniform characteristics, thus indicating a good level of oxidation. In particular, fixed carbide (C; 33.7 wt.%) with a thickness of about 1mm, and originating from organic substances, was detected inside the walls of the type I pottery, while the deep radial cracks in the outer surfaces of the pottery are thought to have been caused by repeated thermal shocks. Given that all of the pottery except for the type I artifacts are considered to be have been made for storage purposes, those containing talc and tremolite are easy to done liquid storing vessels based on an analysis of their material characteristics. As for the type II relics, which are composed of various minerals and exhibit poor physical properties, they seem to have been used for simple storage purposes. As domestic talc and asbestos mines were concentrated in the areas of Gyeonggi, Gangwon, Chungbuk, and Chungnam, it seems likely that talc and tremolite were produced as contiguous minerals. Considering the distance between the remains in Jungsandong and these mines and their geographical distribution, there is a possibility - albeit somewhat slight - that these mines were developed for the mining of various minerals. Although ultramafic rock masses - such as serpentine capable of generating talc and tremolite - have not been found in the Jungsandong area, limestone and biotite granite containing mica schist have been identified in the northwestern part of Yeongjong Island, indicating that small rock masses might have formed there in the past. Therefore, it is judged necessary to accumulate data on pottery containing talc and tremolite, other than the remains in Jungsandong, and to investigate the rocks and soils in the surrounding area with greater precision. The firing temperatures of the pottery found at the Jungsandong site were interpreted by analyzing the stability ranges of the mineral composition of each type. As a result, they have been estimated to range from 550 to $800^{\circ}C$ for the type I artifacts, and from 550 to $700^{\circ}C$ for the type I, II and IV artifacts. However, these temperatures are not the only factors to have affected their physical properties and firing temperature, and the types, particle sizes, and firing time of the clay should all be taken into consideration.