• 한국환경과학회지
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• 제28권12호
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• pp.1061-1069
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• 2019

Common reed (Phragmites australis) is widespread in reclaimed land and wetland habitats. Every year, the common reed produces extensive colonies by means of underground rhizomes and ground-surface stolons. From an agricultural point of view, the common reed's large biomass is a good material for supplying organic matter. However, it has not yet been studied in terms of seedling production, transplanting conditions, and decomposition characteristics in reclaimed land. Seeds were harvested from the native common reed in Saemangeum, South Korea, the previous year and stored on an open field. The seeds were sowed in the greenhouse at the beginning of April. Common reed decomposition was studied from June to September, with the use of coarse mesh (5 mm) stem litterbags, on three samping dates and with five replicate packs per sample. These packs were dug in five soil condition (low-salinity topsoil, subsoil, high-salinity topsoil, subsoil, paddy topsoil) to 0.2 m and 0.4 m depth. The highest germination rate of common reed seeds was observed in non-salt solution, but the exhibited germination rate was 70% at 9.38 dS m^-1. The plant height of young reed decreased steadily with increasing salinity, but leaf number did not decrease by 9.38 dS m^-1. The survival rate of the two-year-old reed was 83.3%, which was 35% higher than that of the one-year reed. The transplant success rate was 0% in the no vinyl mulching in the soil, but the first year and second year seedlings survived rates were 63% and 83.3%, respectively, in vinyl mulching. Common reed decomposition rates were faster low salinity than high salinity. All nutrient contents were found to fluctuate significantly with time by soil conditions. We also need to study the growth rate of reed transplanting seedlings by soil moisture contents and the comparison of degradation in common reed tissues.

• 한국토양비료학회지
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• 제44권5호
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• pp.872-877
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• 2011

인삼재배에서 논전환밭의 이용이 증가하는 추세이며, 개간밭과 더불어 유기물투입의 효과를 조사할 필요가 있다. 토양생물은 유기물의 분해에 영향을 미치는 중요한 요소이기 때문에 유기물 시용이 토양생태계에 미치는 영향을 조사했다. 유박과 퇴비를 개간밭과 논전환밭에 $20Mg\;ha^{-1}$ 와 $40Mg\;ha^{-1}$로 투입하였다. 미생물상 변화는 인지 질지방산을 분석하여 검정하였고, 동물상의 변화는 미소동물의 개체밀도를 측정하였다. 미생물에 대한 PLFA 지수나 미소동물의 밀도는 개간밭보다 논전환밭에서 높았다. 개간밭에서는 유기물 투입에 의한 처리간 차이가 적었다. 논전환밭에서는 퇴비 $40Mg\;ha^{-1}$ 처리구에서 날개응애 밀도가 증가하였고, 이들의 밀도는 곰팡이 PLFA와 양의 상관관계가 나타났다. 위의 결과는 개간밭에서 유기물 함량이나 토양생물의 밀도가 낮은 심토로 개간하면 유기물을 투입하여도 토양생물에 대한 효과가 적을 수 있다는 것을 보여준다. 논전환밭에서는 유기물에 대한 토양생물들의 반응이 다르며 토양의 물리화학성도 토양생태계에 영향을 미칠 수 있다. 논전환밭과 개간밭에서는 유기물에 대한 토양생물의 반응이 다르므로, 투입된 유기물의 분해나 이에 따른 양분의 순환이 다를 수 있기 때문에 두 토양에서 시비방법을 다르게 할 필요성이 있다고 생각된다.

• 한국환경과학회지
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• 제31권11호
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• pp.911-922
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• 2022

To restore reclaimed land, it needs to be supplemented with organic matter; this is especially true for Korea, where organic matter constitutes only one-tenth of conventional agricultural soils. The giant Miscanthus, a perennial grass known for its extensive biomass, shows signs of being an excellent source of organic matter for restoring reclaimed land. Therefore, the objectives of this study were to (i) evaluate the feasibility of using the giant miscanthus as an organic resource within the context of re-using reclaimed land for agricultural purposes (i.e., potato cultivation), and (ii) determine the optimum fertilization rate for the potatoes while the giant miscanthus is being used as an organic resource. Our results show that after 180 days, giant miscanthus lost 23-47% of its original dry weight, with the extent of the loss dependent on soil salinity. Nutrient concentrations (Mg2+, Na+) continued to increase until the end of the study period. In contrast, potassium (K+) and the ratio of carbon to nitrogen (C/N) decreased until the end of the study period. Specifically, after 180 days, low salinity topsoil treatments had the lowest C/N ratio. In the first year, 150 % of standard N rates were required for the potatoes to achieve maximum productivity; however in the 2nd year, standard rates were sufficient to achieve maximum productivity. Overall, this implies that even though the application of giant miscanthus did eventually improve soil quality, increasing crop yields, N fertilization is still necessary for the best outcomes.

• 미생물학회지
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• 제7권1호
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• pp.29-40
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• 1969

Two kinds of organic materials, powders of Salicornia and Oryza sativa L. wre added as a source of organic matter to the suspensions of saline soils(soil : water = 1:3) to be 4 per cent of dried saline soil grams. And then, the samples were incubated at $28^{\circ}C$ to improve the decomposition of organic materials by soil microflora. Resutls of this experiment are summarized as followings : 1) The pH of soil suspension showed its highest value on the second or third week after the treatments, which were similar to those of the soil microflora. Results of this experiment are summarized as follwings : 1) The pH of soil suspension showed its highest value on the second ot third week after the treatments, which were similar to those of the soil microflora populations. 2) Salinity increased up to the second week and the highest value of it appeared in the samples which were treated with the powder of Salicornia. In general, the salinity of all samples decreased on the third week after the treatment. The fact was assumed the possibilities of desalination from saline soil by the microbial actions. 3) Soil microflora such as bacteria, actinomycetes and fungi, were determined its populations soil microflora is to act as decomposer in soil. Both of the bacteria and actinomycytes population showed in the third weak after the tratment. In general, 30-years old of saline soil contained microbial population much more than those of 5-year old of saline soil. Salicornia powder favored the increase of both the bacteria and fungal population, and Oryza sativa L. seemed to have been a great role in increase of actinomycetes. Especially, fungal population of the untreated soil suspension contained higher microbial populations more than those of the soils treated with both of the organic materials. 4) Sugar contents of soil suspesions decreased remarkably on the first week after the treatments. 5) The amount of nitrate had similar tendency to those of population changes of soil microflora. Total acidity decreased continuously and the amount of potassium showed its highest value on the third week treatment. However, the amount of phosphorus was determined to be insignificant.