토탄과 같은 자연소재를 이용한 자연친화적인 연안 저질개선제 살포가 꼬막의 혈액학적 성상 몇 근육 글리코겐 함량에 미치는 영향에 대하여 알아보기 위하여 실내 실험을 실시하였다. 저질개선제를 단위면적(m2)당 0, 100, 300, 800g의 양을 살포 후 10일 동안 숙성시킨 꼬막을 수조에 수용하여 14일 동안 사육 실험한 결과 저질개선제를 단위면적(m2)당 800g 살포한 구에서 48시간 후에 1개체가 폐사한 것 이외에 심험종료까지 폐사가 일어나지 않아 자연소재로 구성된 저질개선제가 생물 자체에는 직접적인 독성을 나타내지 않는 것으로 판단된다. 꼬막 혈액의 전혈량, 헤마토크리트값, 헤모글로빈량에 있어서는 저질개선제 살포 농도별 큰 차이를 보이지 않았으나 혈액 글루코스량 및 근육 글리코겐량은 대조구와 비교하여 증가하는 경향이었다.

During the excavation to find ancient rice seeds from the peat layer (12,500-14,800 bp based on 14 dating samples) of Soro-ri, Cheongwon-gun near Cheongju city, we found not only old rice seeds, but also other organic materials including insect fossil skeletons. Although no complete specimen was found in this study, some body parts were diagnotic enough for identifying species. Among the identified insect fossils, two species were successfully identified based on their characteristic forewing morphologies, e.g., cross-ridges on forewing. The two identified species, Plateumaris sericea and Donacia flemola or near, belong to Donaciinae in Chrysomelidae, and their larvae are known to feed on the root of wetland plants, mainly in Poaceae or Cyperaceae. Such finding proved that a wetland environment was maintained in Soro-ri at that time, and was suitable for such insects to survive. Therefore, evidence from the fossilized rice seeds, together with these insect fossils, clearly proved that the environment at that time was suitable for rice, a common Poaceae species, growing.