임목폐기물의 현장 재활용을 통한 생태복원기술의 적용 및 평가 = (The) application and evaluation of ecological restoration techniques using on-site wood waste recycling

국문 초록 (Abstract)

본 연구는 건설현장에서 발생되는 임목폐기물을 현장 내 또는 퇴비화공장에서의 퇴비화를 통하여 톱밥퇴비 등의 유기질계 식생기반재를 대체하고, 미분해 임목파쇄칩을 식생기반재와 혼합하여 사용하는 등 임목폐기물의 재활용을 촉진하는 다양한 생태복원기술을 적용하는데 있다. 아울러, 재래목본·초본의 적극적 도입을 위하여 침지법에 의한 종자의 전처리로 발아율 향상과 조기발아를 유도함으로써 종다양성을 확보한 수림화 복원목표에 부합되는 식물상을 형성하고자 하였으며, 본 연구의 결과는 다음과 같았다.
1. 임목파쇄칩을 퇴비화하기 위해서 50㎜이하의 임목파쇄칩에 질소원으로 돈분 또는 돈분+비료를 사용한 실험구에서, 실험착수 후 9일과 3일만에 49.0℃와 40.4℃의 고온에 도달하였고, 발열 지속기간이 7일간과 4일간으로 나타났으며, C/N비는 각각 26.5와 25.3을 나타내어 부숙퇴비의 기준(C/N비 25.0~40.0)에 적합한 것으로 나타났다. 또한, 미생물 접종원으로 마사토와 미생물제재를 혼합한 실험구에서 실험착수후 10일만에 67.6℃의 고온에 도달하여 16일간 지속되었으며, 미생물수의 경우 마사토를 사용한 실험구에서 5.3×10^(8)CFU/g로 가장 높게 나타났다. 임목폐기물의 발생 현장내 퇴비화를 위한 실험에서는 질소공급원인 돈분의 사용이 제한됨에 따라 비료와 마사토를 사용한 실험구에서 실험시작 후 3일만에 54.7℃의 고온에 도달하여 17일간 발열상태를 유지하였고, C/N비도 30.6으로 퇴비화 기준에 충족되는 것으로 나타났다.
2. 임목파쇄퇴비만을 사용한 실험구와 임목파쇄칩을 15% 혼합한 실험구의 3개월 경과시점의 출현종수는 각각 10.0종과 9.4종으로 임목파쇄칩을 30%이상 혼합한 실험구보다 종다양도가 높게 나타났다. 피복율은 임목파쇄퇴비와 톱밥돈분퇴비를 사용한 실험구에서 각각 73.3%와 70.0%로 높게 나타났으며, 임목파쇄칩을 15%이상 혼합한 실험구는 46.7%이하로 낮게 나타났다.
3. 미분해 임목파쇄칩을 식생기반재취부공법의 사용재료와 3 : 7의 비율로 혼합하여 식생기반재로 사용한 얇은식생기반재취부공법(1㎝, 3㎝)의 평균 출현종수는 시공후 4개월 경과시까지는 임목파쇄칩을 혼합한 실험구에서 대조구에 비해 각각 2.3종과 1.0종이 적게 나타났으나, 17개월 경과시점에서는 임목파쇄칩을 혼합한 실험구에서 각각 2.7종과 0.7종이 많았다. 두꺼운식생기반재취부공법(10㎝)의 평균 출현종수는 4개월 경과시까지는 임목파쇄칩을 혼합한 실험구에서 대조구보다 0.7종이 적었고, 17개월 경과시점에서는 임목파쇄칩을 혼합한 실험구에서 1.4종이 많게 나타났다. 식생피복율은 4개월까지는 실험구가 대조구에 비해 5~10% 정도 높았고, 17개월 경과시점에서는 모든 실험구에서 90%이상의 피복율을 나타내었다.
4. 하수오니를 주원료로 사용하는 식생기반재의 비중은 1.20~1.36이었고, 임목폐기물을 재활용한 식생기반재의 비중은 0.75~0.83이었으며, 토양수분 보유능력은 평균 10~20%정도 향상되었다. 임목파쇄칩을 사용한 식생기반재의 토양경도는 시공후 10일 경과시에도 20.7㎜로 식물생육에 적합하였으며, 17개월 후에는 전질소량이 모든 실험구에서 1.79%이상으로 나타나 식생기반재의 기준치인 0.06%보다 월등히 높게 나타났다.
5. 침지법에 의한 재래목본 및 초본 종자의 발아실험에서 대조구에 비해 자귀나무는 액체영양배지에서 13.4%, 붉나무는 미생물배양액에서 23.4%, 참싸리는 증류수에서 33.4%, 비수리는 액체영양배지에서 31.1%, 억새는 증류수에서 23.3%의 발아율 증가를 나타내었다. 반면, 낭아초는 대조구에서 75.5% 이상의 발아율로 가장 높았으며, 소나무와 단풍나무는 발아되지 않았다.
6. 침전처리 후 건조시간에 따른 발아율의 변화에서는 모든 공시식물에서 처리직후 또는 1일 이내에 파종하는 것이 가장 효과적이었다. 또한, 비탈면 녹화용으로 사용되는 대부분의 식물들은 포장 발아율에 비해 발아상 발아율이 높다고 알려져 있으나, 자귀나무의 경우에는 포장 발아율이 발아상 발아율보다 높게 나타났다.
7. 참싸리, 낭아초, 비수리는 토양에서의 최초 발아시기가 4.1~5.9일로 나타나 한지형잔디와 혼파할 경우에도 경쟁할 수 있을 것으로 판단된다. 반면, 자귀나무, 붉나무, 안고초는 8.0~10.4일이 소요되어 발아시기를 단축시키는 처리방법이 요구된다.

다국어 초록 (Multilingual Abstract)

The main part of this study covers the following: Finding a solution for fresh wood chips to be used as an alternative growing-media through a study of the formation method of a compost base that is applicable on both construction site and composting factory to ferment fresh wood chips produced from construction site as well as a study on adjuvant or secondary materials; Finding the possibility of ecological restoration for ruined area using fresh wood chips as a main material applying various treatment techniques that could motivate recycling of fresh wood chips including use of on-site crushed fresh wood chips mixed with common growing-media. The secondary part of this study was carried out to establish an ideal flora that is suited to the goal of tree-centered restoration which will assure diversity of species through inciting of early germination and increased germination rate by treatment using precipitation method. Followings are the summary of this study.
1. The result from the experiment plot using wood chips sized 50㎜ or less, manure and fertilizer mixed manure as a source of nitrogen to compost fresh wood chips has shown that the temperatures 9days and 3days after the beginning of the experiment reached to 49.0℃ and 40.4℃ respectively, the heating duration was 7days and 4days respectively, and the C/N ratio was 26.5 and 25.3, each satisfying the standard for composted manure(25.0~40.0). Also, the other result from another experiment plot using mixture of sandy soil and microorganism as an inoculation source of microorganism has shown that the temperature 10days after the beginning of the experiment reached to 67.6℃ and lasted 16days. The experiment plot using sandy soil has shown the highest figure of 5.3×10^(8) CFU/g in terms of number of microorganism. The result from the experiment plots for on-site composting of fresh wood chips have shown that the experiment plot that used sandy soil with fertilizer due to supply restriction of manure as a nitrogen source in construction site reached the high temperature of 54.7℃ after 3days of experiment beginning and maintained heating state for 17days and reached 30.6 of C/N ratio, satisfying the standard for composted manure.
2. The experiment using composted wood chips only and composted wood chips with 15% fresh wood chips showed 10.0 and 9.4 appeared species 3 months after the beginning of the experiment. These figures display higher diversity of species than that seen in the experiment with 30% fresh wood chips mixed in composted wood chips as a growing-media. In terms of coverage ratio, the composted wood chip plot and the sawdust-manure plot have shown higher coverage ratio of 73.3% and 70.0% respectively. While the 15% fresh wood chip added plot showed the initial coverage of 75% and reduced to 46.7% after 3months.
3. Average appearanced species from the Thin-Media-Spraying-Method(1㎝ and 3㎝ thickness) plots that used mixture of fresh wood chips and common growing-media at 3:7 ratio were lower by 2.3 and 1.0 respectively at the time of 4 months after installation compared to the common growing-media only plots, which showed higher number of appeared species by 2.7 and 0.7 respectively at the time of 17 months after installation. Average appearanced species from the Thick-Media-Spraying-Method(10㎝ thickness) plot that used same mixture 3:7 ratio of mixture of fresh wood chips and common growing-media was lower by 0.7 at the time of 4 months after installation compared to the common growing-media only plot, while it was higher by 1.4 at the time of 17 months after installation. The coverage rates according to mixture or non-mixture of fresh wood chips in each experiment plots have shown the difference of 5% to 10% until 4 months, while no difference was observed 17months resulting in over 90% coverage rates in all experiment plots.
4. Specific gravity of the sewage sludge growing-media was 1.20 to 1.36, while that for the recycled fresh wood chip growing-media was 0.75 to 0.83 which enables the fresh wood chip growing-media lessen the falling chances after onstruction. Also, moisture holding capacity of the recycled fresh wood chip growing-media was increased by 10% to 20% attributed to increased porosity in the media. Soil hardness of the recycled fresh wood chip growing-media after 10 days of construction was 20.7㎜ which is suitable for plant growth. Also, chemical analysis of the media after 17 months of installation showed that the total nitrogen of all experiment plots were more than 1.79% which is higher than the standard for growing-media of 0.06% showing no nitrogen deficiency phenomenon that could be expected when non-composted fresh wood chip was used.
5. The experiment to verify the effectiveness of precipitation method for Native Herbs and Native Shrubs to secure diversity of species for ruined slope has shown increased germination rate of 13.4% for Albizzia julibrissin in nutrient broth, 23.4% for Rhus chinensis in microorganism broth, 33.4% for Lespedeza cyrtobotrya in distilled water, 31.1% for Lespedeza cuneata in nutrient broth and 23.3% for Miscanthus cuneata in distilled water respectively compared to non-treated control base. On the other hand, germination rate of Indigofera peseudo-tinctoria has resulted more than 75.5% in non-treated control base only and all the other treated bases have resulted in germination rates of less than 75.5% suggesting that the precipitation method could have negative effect on Indigofera peseudo-tinctoria. No germination was observed for Pinus densiflora and Acer buergerianum.
6. The most suitable dry time after the precipitation method treatment was observed to be immediately after the treatment of all tested plants, which have shown increased germination rate and the maximum of one day of drying could help to enhance the germination rate. It is generally known that the germination rate in incubator is higher than the that in soil for most plants that are generally used for slope restoration. But, this study has shown that the germination rate of Albizzia julibrissin in soil was higher than that in incubator depending on the method of treatment.
7. Exotic Grass is generally used for slope restoration characterized by early germination and vigorous growth. In line with this, it is necessary for Native Shrubs and Native Herbs to be treated before being seeded to shorten their germination stage if they are going to be seeded with Exotic Grass. This study shows that Lespedeza cyrtobotrya, indigofera peseudo-tinctoria and Lespedeza cuneata could compete with Exotic Grass since their initial germination period was 4.1 to 5.9 days. On the contrary Albizzia julibrissin, Rhus chinensis and Arundinella hirta took 8.0 to 10.4 days requiring a treatment to shorten the germination period.

목차 (Table of Contents)

• Ⅰ. 서론 = 1
• Ⅱ. 연구사 = 5
• 1. 비탈면녹화의 변천사 = 6
• 2. 임목폐기물의 재활용 = 13
• 3. 수림화복원과 종자의 발아촉진 = 18
• Ⅲ. 재료 및 방법 = 24
• 1. 임목폐기물을 재활용한 식생기반재 = 24
• 1.1 임목파쇄칩의 퇴비화 = 25
• 1.2 임목파쇄퇴비와 파쇄칩의 적정 배합비 = 34
• 1.3 임목파쇄퇴칩을 혼합한 식생기반재의 현장 적용성 평가 = 38
• 2. 침지법을 이용한 종자의 발아 = 44
• 2.1 공시 식물 = 44
• 2.2 미생물의 분리 = 44
• 2.3 발아상 발아율 = 45
• 2.4 토양에서의 발아율 = 46
• 2.5 통계 처리 = 46
• Ⅳ. 결과 및 고찰 = 47
• 1. 임목폐기물을 재활용한 식생기반재 = 47
• 2. 침지법을 이용한 종자의 발아 = 79
• 3. 종합 고찰 = 109
• Ⅴ. 결론 = 124
• Ⅵ. 인용문헌 = 127
• LIST OF TABLES = 139
• LIST OF FIGURES = 144
• (Abstract) = 146