• 한국환경복원기술학회지
• /
• 제13권6호
• /
• pp.75-86
• /
• 2010

This study used a phytosociolocal approach in classifying the vegetation communities of evergreen broad-leaved forest in Gageodo island of Korea, and the results are as follows: Quercus acuta community was classified into Dendropanax morbifer subcommunity, Daphniphyllum macropodum subcommunity, and Quercus acuta typical subcommunity. In the study sites, soil organic matter, total nitrogen, available phosphorous, exchangeable K, exchangeable Ca, exchangeable Mg, cation exchange capacity, and soil pH were ranged from 15.23~18.89%, 0.73~0.99%, 4.31~15.06 (mg/kg), 1.09~1.13 ($cmol^+$/kg), 21~7.15 ($cmol^+$/kg), 1.33~2.10 ($cmol^+$/kg), 33.04~38.28 ($cmol^+$/kg) and 4.47~4.83 respectively. The Dendropanax morbifer subcommunity were found in sites with high percentage of organic matter, total nitrogen, and low percentage of exchangeable Mg and Ca while the Daphniphyllum macropodum subcommunity were found in sites with low percentage of organic matter, total nitrogen, exchangeable Mg and Ca. The Quercus acuta typical subcommunity were found in sites with high percentage of organic matter, total nitrogen, exchangeable Mg and Ca. It is urgently needed to work for the preparation of an island management plan to the levels of species through habitat conservation.

• 한국환경복원기술학회지
• /
• 제13권6호
• /
• pp.97-106
• /
• 2010

Earthworm, a prominent ecosystem engineer within many terrestrial ecosystems, can exert profound influences on various abiotic/biotic environments through bioturbation processes such as burrowing, casting and mixing of litter and soil. In this study, we investigated how the presence or absence of earthworm (Oligochaeta) can alter the soil physico-chemical conditions and ultimately the distribution and abundance of Collembola which constitutes a large proportion of the soil fauna. During September 2010, soil organisms along with soil samples were collected from randomly installed 20 plots in Mt. Gwan-ak. We examined the differences in the abundance of Collembola among plot samples in respect to the presence/absence of earthworm and soil physico-chemical conditions (i.e., pH, $PO_4^{3-}$, $NO_3^{2-}$, organic matter (OM), electrical conductance and water content). Analysis of soil physico-chemical environment revealed a significantly higher organic matter content and electrical conductance in plots with earthworm compared to plots without earthworm. Abundance of Collembola were not only higher in plots with earthworm than in plots without earthworm, but were also positively correlated with availability of OM present in the environment. The results suggest that positive impacts of earthworm on the abundance of Collembola in this study may have been due to their ability to effectively modify soil physico-chemical conditions favored by Collembola. Such conspicuous influence of earthworm's activity on below-ground community suggests their potential significance in forest restoration or revegetation process.

• 한국안전학회지
• /
• 제26권4호
• /
• pp.111-119
• /
• 2011

This study was designed to provide basic data applicable to fire investigation through consideration of combustion products and propose vulnerability of combustibles through analysis of $CO_2$ emission. In order to achieve these research objectives, characteristics of combustion products such as smoke release rate of each part(raw leaves, branches and barks), $CO_2$ emission and ash production were considered targeting on 6 oak species(Quercus variabilis Blume, Quercus aliena Blume, Quercus serrata, Quercus mongolica Fisch, Quercus dentata Sapling and Quercus acutissima) using cone calorimeter and smoke density tester. As a result, it was found that raw leaves release smoke more relatively than branches and barks, when they burn, and that Quercus variabilis Blume has the highest smoke density. Also, Quercus acutissima released CO and $CO_2$ which are respectively, 6.67 times and 1.43 times more than Quercus variabilis Blume with low $CO_2$ emission. In addition, branches released CO and $CO_2$ more relatively. There was a big difference in ash production among raw leaves(3.1 g), branches(10.5 g) and barks(16.43 g). It was identified that Quercus serrata produces ashes which are nearly 9.95 times more than Quercus variabilis Blume. It demonstrates that Quercus serrata contains relatively higher minerals and that Quercus variabilis Blume can leave lots of traces like stain and carbonization, as it releases smoke a lot and it's difficult to predict visibility, when a forest fire breaks out in its community area. It is also considered that smoke particles containing oil in the air leave strain on the surface of a tree, and that CO and $CO_2$ emission increases, when crown fire to burn branches breaks out.

• 농촌지도와개발
• /
• 제26권2호
• /
• pp.85-97
• /
• 2019

The conflict management of forest recreation, especially conflict management between hikers and MTB users, has drawn much attention as one of major issues in forest policy making. The main purpose of this study was to investigate hikers' conflict perception against MTB users and their attitudes toward the necessity of conflict management actions, and to identify factors influencing those attitudes. The research data were collected through online surveys of 644 men and women hikers who are aged 20 or older and not participating in MTB riding. The major findings of this study can be summarized as follows: First, the levels of goal interference and social value conflicts against MTB users were not so high, but rather, the awareness level of compatibility was much higher than that of conflict, and hikers' awareness level of safety risks posed by MTB users was also considerably high. Second, hikers' attitudes toward the necessity of conflict management actions were generally shown to be considerably positive, but those attitudes toward indirect management actions such as information, education, and compliance with norms of conduct, were significantly positive than those attitudes toward direct management measures such as zoning, enforcement, and regulations. Finally, the results of the multiple regression analysis showed that four factors that most significantly affect hikers' attitudes toward direct or indirect conflict management actions are behavioral norms conflict, safety risk, compatibility and age. Safety risks had most important influence on hikers' attitudes toward the direct management actions, but behavioral norms conflicts had most important influence on indirect management actions.

• 농업과학연구
• /
• 제49권2호
• /
• pp.215-226
• /
• 2022

This study aims to investigate the soil environment characteristics of the Abies koreana community, which is currently showing a continuous decline in its size, in order to provide fundamental data for the management and creation of a conservation plan for the Abies koreana communities at the Korean national parks of Sobaeksan, Deogyusan, and Jirisan. Soil depth investigations were conducted at depths deeper than 40 cm into the B horizon at most study sites, except for the Dwaejipyeongjeon and Byeoksoryeong sites. The soil water content exceeded 30% on average, and these soils showed low bulk density levels. The soil texture was found to be the loamy or silty loam type at most study sites. It was also found in a chemical characteristic assessment that the soil samples contained more than 10% organic matter at most study sites. The cation exchange capacity (C.E.C.) and total N concentration levels were also high at most study sites. However, the soil showed low exchangeable K⁺, Na⁺, Ca²⁺, and Mg²⁺ levels at most study sites. Finally, the pH values were 4.90, 4.53, and 4.60 at soil depths of 10 cm at the Sobaeksan, Deogyusan and Jirisan sites, respectively, outcomes that are notably lower than the average levels in soil from Korean forests according to the literature. This appears to be due to the cold and wet climate of these subalpine regions given the reduced leaf-litter decomposition rate and accumulation of organic acids.

• 산업경영시스템학회지
• /
• 제47권1호
• /
• pp.41-50
• /
• 2024

Korea is facing a significant problem with historically low fertility rates, which is becoming a major social issue affecting the economy, labor force, and national security. This study analyzes the factors contributing to the regional gap in fertility rates and derives policy implications. The government and local authorities are implementing a range of policies to address the issue of low fertility. To establish an effective strategy, it is essential to identify the primary factors that contribute to regional disparities. This study identifies these factors and explores policy implications through machine learning and explainable artificial intelligence. The study also examines the influence of media and public opinion on childbirth in Korea by incorporating news and online community sentiment, as well as sentiment fear indices, as independent variables. To establish the relationship between regional fertility rates and factors, the study employs four machine learning models: multiple linear regression, XGBoost, Random Forest, and Support Vector Regression. Support Vector Regression, XGBoost, and Random Forest significantly outperform linear regression, highlighting the importance of machine learning models in explaining non-linear relationships with numerous variables. A factor analysis using SHAP is then conducted. The unemployment rate, Regional Gross Domestic Product per Capita, Women's Participation in Economic Activities, Number of Crimes Committed, Average Age of First Marriage, and Private Education Expenses significantly impact regional fertility rates. However, the degree of impact of the factors affecting fertility may vary by region, suggesting the need for policies tailored to the characteristics of each region, not just an overall ranking of factors.

• 한국환경농학회지
• /
• 제32권3호
• /
• pp.185-192
• /
• 2013

농촌인구의 감소와 잉여생산작물로 변화된 쌀의 수요에 대비해 최근 20-30년간 휴경논, 즉 묵논이 증가하여 왔으나, 새로운 작물재배지로의 전환 또는 용도지역 변경으로 인한 형질변경이 수반되지 않는 오지의 묵논은 점차 식물생태복원의 주요한 입지로 새롭게 부각되고 있다. 묵논의 입지적, 수리적 여건상 묵밭에 비해 식물의 천이가 활발하고, 습지로서의 기능과 다양한 생물 서식지로서의 기능 등 생태적으로 긍정적인 역할을 담당하게 될 묵논은 연차별로 식물군락의 변화양상이 달라진다. 본 연구에서는 우리나라 전역에 분포하는 묵논을 대상으로 초기, 중기, 후기묵논으로 구분짓고, 각 시기별 식물군락의 변화양상에 대한 식물사회학적 연구가 수행되었다. 강원 경기 5개 권역, 충청남 북 2개 권역, 경상남 북 18개 권역, 전라남 북 10개 권역 등 총 35개 권역을 대상으로 총 203개소의 조사구에서 획득한 식생조사표를 이용하여 군락분류, 군락생태, 군락동태에 대한 비교분석이 이루어졌다. 본 연구를 통해 우리나라 초기, 중기, 후기의 천이단계별 식물군락은 각각 뚝새풀군락, 골풀군락, 버드나무군락으로 특징지어졌으며, 삼림 내 묵논 일부 지역에서 드물게 후기천이 단계에서 오리나무군락이 분포하는 것으로 확인되었다. 이러한 군락의 발달은 대기후적, 지리적 조건과 관계없이 유사한 패턴을 보였다. 묵논식생의 천이단계는 일년생식물기-다년생식물기-관목식물기-교목림기로 발달해가는 천이단계로 구분할 수 있으나 중기묵논에서는 단계별 우점종이 뚜렷이 구분되지 않고 여러 종이 유사한 우점도로 혼생하였다. 군락분류를 통한 우리나라의 연차별 묵논의 식생특성을 분석한 결과, 새로운 생태복원모델로 관심이 높아지는 묵논식생의 변화양상을 파악하였으며, 이러한 결과는 휴경지의 생태복원 및 보전을 위한 기초 자료로써 매우 유효한 정보를 제공하게 될 것으로 기대된다.

• 한국환경생태학회지
• /
• 제23권6호
• /
• pp.506-515
• /
• 2009

본 논문은 2006년 3월부터 11월까지 전라남도 북부지역 7개 시 군 지역에서 각 2곳을 선택하여 총 14개 조사 지역에서 외래식물과 귀화식물의 도시화지수를 분석하였다. 귀화식물은 26과 79속 105종 6변종 111종류로 확인되었다. 도시화지수는 함평군이 21.95%로 가장 높았으며 곡성군이 16.38%로 가장 낮았다. 귀화식물 과별 출현종류는 국화과가 36종류(32.43%)로 가장 많았고, 벼과 17종류(15.31%), 콩과 7종류(6.31%) 순이었다. 주요 귀화식물군락은 군락조성표에 따라서 아까시나무와 족제비싸리군락, 개망초군락 및 망초군락 등 21개 군락이 확인 되었다. 생태계 위해귀화식물은 털물참새피, 물참새피, 애기수영, 도깨비가지, 미국쑥부쟁이, 돼지풀 및 단풍잎돼지풀 등 7종이었다. 국가 차원에서 외래종의 통합관리방안이 필요하지만 외래종분포를 확인하여 지속적인 관리를 하는 것이 자생종의 보전과 보호에 있어서 매우 중요한 역할을 하게 될 것이다.

• 한국자원식물학회지
• /
• 제20권5호
• /
• pp.375-382
• /
• 2007

본 연구는 석불산 일대의 관속식물상과 식생을 조사하여 식물종의 분포 양상을 알림으로서 식물자원의 효율적 이용에 일조하고자 수행한 바 다음과 같은 결론을 도출하였다. 석불산 일대의 관속식물상은 96과 249속 293종 2아종 43변종 3품종 1재배종으로 총 342종류가 확인되었다. 희귀식물에는 나도개감채(보존우선순위; 169번)와 쥐방울덩굴(151번)이 확인되었으며, 특산식물에는 민땅비싸리, 산철쭉, 개나리(식재종), 병꽃나무, 개비자나무, 지리대사초, 은사시나무(식재종)가 확인되었다. 식물구계학적 특정식물종에는 V등급과 II등급에 해당하는 식물은 출현하지 않았으며, IV등급에는 등나무가(식재종), III등급에는 나도개감채, 단풍나무가, I등급에는 개비자나무, 민바랭이새, 굴참나무, 참느릅나무, 송악, 쥐방울덩굴, 산돌배, 예덕나무, 물오리나무, 말오줌때, 동백나무(식재종), 거지덩굴, 장구밥나무, 정금나무, 큰엉겅퀴로 총 18종류가 확인되었다. 귀화식물에는 11과 26속 32종 2변종으로 총 34종류가 확인되었으며, 귀화율은 전체 342종류의 관속식물 중 9.9%로 분석되었다. 석불산 일대의 식물군락에는 조사구내에 출현하는 식물들의 우점도와 군도를 조사한 후 종조성표를 작성하여 군락을 선정한 결과, 3개의 조사구는 소나무군락으로, 1개의 조사구는 곰솔군락으로 분류되었다.

• 생명과학회지
• /
• 제31권4호
• /
• pp.377-384
• /
• 2021

진달래(Rhododendron mucronulatum)는 우리나라에서 어렵지 않게 볼 수 있는 개화식물로 꽃이 아름다워 관상목으로 이용되고 있고 생태학적, 약리적으로 잠재력이 있는 중요한 산림자원이다. 우리나라의 대표적 진달래나무군락지인 비슬산군립공원에서 진달래나무 아래의 토양을 채집하여 그 진균 군집의 특성을 조사하였다. 위치와 계절에 따른 진균 군집의 차이를 확인하기 위하여 토양 샘플은 총 3개의 위치에서 2월과 8월에 각각 한번씩 채집하였다. Pyrosequencing을 통해 총 454,157개의 서열을 얻을 수 있었다. 첫번째 채집포인트에서 얻은 샘플의 진균 군집이 6개 샘플 중 가장 종 풍부도가 높았고 가장 다양한 진균들로 구성되어 있음을 확인하였다. 분류 단위 별 분석으로는, Basidiomycota, Ascomycota, Mortierellomycota가 대표적인 문(phylum)으로 나타났으며, Agaricales_f, Mortierellaceae, Clavariaceae가 주요한 과(family)인 것으로 분석되었다. Mortierella 속(genus)은 모든 샘플중에서 가장 우점한 속이었다. 또한 총 진달래와 관련이 있는 것으로 추정되는 19개의 속이 확인되었다. 8월에 채집한 샘플에서 위치에 따라 각각 109개, 111개, 112개의 특이적인 속이 발견되었고, 2월의 샘플과 비교했을 때 2월의 샘플에는 존재하지 않는 28개의 공통된 속이 발견되었다. 이 연구는 추후 진달래나무에 특이적인 진균의 새로운 종을 규명하거나 토양 진균류와 식물의 상호작용을 규명하는 기초자료로 활용될 수 있다.