• Title/Summary/Keyword: annual weeds

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Investigation on ecological habitats in Armillaria gallica mushrooms (천마버섯(Armillaria gallica )의 생태학적 서식지 조사)

  • Yoo, Young Bok;Oh, Jin A;Oh, Youn Lee;Moon, Jiwon;Shin, Pyung Gyun;Jang, Kab Yeul;Kong, Won-Sik
    • Journal of Mushroom
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    • v.11 no.1
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    • pp.36-40
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    • 2013
  • Armillaria gallica was ecologically surveyed to investigate its relationship with Gastrodia elata in cultivation areas of Korea in 2012. In the observation made around October 17 in the area of Namyangju (Gyeonggi), Sangju (Gyeongbuk) and Gimcheon (Gyeongbuk) in Korea, the fruit bodies of A. gallica were consistently found near the cultivation areas of Gastrodia elata across these cultivation areas. Since the temperature and rainfall have been considered as important factors of fruiting of A. gallica, we checked the temperature and rainfall around two weeks ago of mushroom fruiting. The average temperature of all cultivation areas was $9.9{\sim}17.5^{\circ}C$ (the lowest temp.: $3{\sim}23^{\circ}C$, the highest temp.: $15{\sim}26^{\circ}C$) and the annual rainfall was 0.5~1.0mm on October 10 which can be compared to 2.5~4.5mm on October 17. Fruiting bodies were generally developed at weedy field in which G. elata were cultivated five years ago. The field was inclined 15 degrees, east-facing and consists of loam. The fruit bodies were formed on both sides of a small ditch between the Gastrodia elata cultivation fields and neighboring fields, and the areas were common weeds and moisture at all times. The fruiting bodies were growing above the soil rather than oak wood. Gregarious, but also occurs to 1-5 fruiting bodies occur sporadically. Results observed in detail the growing areas, some fruit bodies were developed along the black and thick rhizomorph formation.

Studies on Application Method and Safety of Macrogranule(GG) Herbicide for Remote-controlled Aerial Application (무인헬기용 Macrogranule(GG) 제초제의 안정성 및 살포방법 연구)

  • Yoon, Cheol-Su;Bae, Chang-Hyu;Lee, Sheong-Chun;Kim, Kyung-Hyun;Lee, Kye-Hwan;Cho, Tae-Kyoung;Hwang, In-Cheon
    • Korean Journal of Weed Science
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    • v.31 no.3
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    • pp.294-307
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    • 2011
  • This experiment carried out to confirm characteristics of macrogranule (GG) for herbicidal efficacy by using remote-controlled aerial application (RCAA) to control annual and perennial weeds in rice paddy field, application methods, and application times of formulation types. Particle of 500 g GG having average diameter of 2.5~3 mm was over 85 percent, the bulk density of the particle was $0.2\sim0.4g\;mL^{-1}$ and the particle was water floating granule. Active ingredients and external form of halosulfuronmethyl+mefenacet GG remained stable under condition of storage stability test. The disintegration time of the GG was faster as the water temperature was increased. But disintegration time was not affected by pH on the water conditions. By using hand, spoon and power applicator, drift distances of GG were 4~5m, 7 m and 10~12 m, respectively. GG showed good herbicidal efficacy and plant safety in all of the application methods such as, using hand, spoon, power applicator and RCAA. Application times of GG, GR, SC and TB by hand in $4,000m^2$ were 38 min. 4 sec, 42 min. 20 sec, 38 min. 10 sec and 21 min. 4 sec, respectively, but application time of GG by using RCAA was 1 min 32 sec. According to appearance and characteristics of formulation types, suspension concentrate (SC) and GG were possible formulation types for RCAA.

Community patterns of demersal fishes by the baited traps and bottom gillnets in the Masan Bay , heavily polluted area (마산만에서 통발과 자망어구에 의한 저서 어개류의 군집특성)

  • 염말구
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.33 no.4
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    • pp.298-310
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    • 1997
  • The aim of this research was to evaluate the biotic environments based upon the community pattern of demersal fishes in the Masan bay which is heavily polluted area in the southern part of Korea. The baited traps or bottom gillnet sampled bottom fishes at four sites totally 14 tunes from March 1994 to December 1996 with 2~3 months interval. The baited trap caught 0~ 10 species which were mainly starfish, crabs, conger eel, rockfish, or blenny with 0~50 individuals per a trap. Small crab(Atergatis sp.) was significantly dominant in the S1 site, most heavily polluted area, and starfish(Asterias sp. and/or Asterina sp.) in the other three sites. There was no animals at the S1 site in the March and July in 1994 and August in 1996. The gillnets caught 0~7 species which were mainly mantis shrimp, jellyfish, flounder, starfish, crabs, or sea weeds with 0~30 individuals per a pannel of bottom gillnet. Jellyfish was significantly dominant in the S1 site and mantis shrimp in the all four sites. There was no animals in the July 1994 at S1 site and in the August and December 1996 at S4 site. But at the August in 1995 or 1996 in the S1 site, the bottom gillnets caught mackerel, anchovy, gizzard-shad or mullet which was dead all. The species diversity index of samlings by trap or gillnet showed less than 1.0 in the 80% of the totally 56 samplings. This means that the stability of demersal fishes' community is very low owing to the poor biotic environments. But most of fishes living at Masan bay appeared well fitting with the heavily polluted environments. And some fishes, like mackerel, anchovy, gizzard-shad or mullet migrated into polluted Masan bay with the seasonal or annual fluctuation.

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Use of Drainage Water as Irrigation Resource in the Paddy Field to Mitigate Non-point Source Pollutants (배수로 물 관개 벼농사의 비점오염원 경감효과)

  • Kim, Choon-Song;Ko, Jee-Yeon;Lee, Jae-Saeng;Jung, Ki-Yeol;Park, Sung-Tae;Ku, Yeon-Chung;Kang, Hang-Won
    • Korean Journal of Environmental Agriculture
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    • v.26 no.2
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    • pp.107-115
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    • 2007
  • Objective of this study was to assess the efficient rice cultivation practice to mitigate the non-point source pollutants loading to the adjacent watershed. Cultivation practices consisted of machine transplanting, direct seeding on dry paddy, and no tillage in which no fertilizer and pesticide were applied to paddy field. Water in drainage canal was used as irrigation source during the entire rice growing season. Loading of the non-point source pollutants to the adjacent small stream was mitigated by all treatments. Rice yield, total biomass (rice + weeds), and uptake T-N, $P_2O_5$, and $K_2O$ were higher in machine transplanting practice than those in direct seeding and no tillage practices. However, the purification effects of non-point source pollutants were followed in orders of no tillage > direct seeding > machine transplanting due to quantity of irrigation water. The annual purification quantity of T-N, T-P, and K by rice cultivations ranged from 46 to 369 kg $ha^{-1}$, 4.1 to 16.4 kg $ha^{-1}$, and 55 to 238 kg $ha^{-1}$, respectively, during the entire rice growing season. Results revealed that no tillage practice of rice cultivation was the best management option in reducing the loading of the non-point source pollutants from the drainage canal into stream.