• Journal of Ecology and Environment
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• 제43권4호
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• pp.364-375
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• 2019

Background: Ecologists continue to investigate the factors that potentially affect the pattern and magnitude of tree damage during catastrophic windstorms in forests. However, there still is a paucity of research on which trees are more vulnerable to direct damage by winds rather than being knocked down by the fall of another tree. We evaluated this question in a mixed hardwood-softwood forest within the Big Thicket National Preserve (BTNP) of southeast Texas, USA, which was substantially impacted by Hurricane Rita in September 2005. Results: We showed that multiple factors, including tree height, shade-tolerance, height-to-diameter ratio, and neighborhood density (i.e., pre-Rita stem distribution) significantly explained the susceptibility of trees to direct storm damage. We also found that no single factor had pervasive importance over the others and, instead, that all factors were tightly intertwined in a complex way, such that they often complemented each other, and that they contributed simultaneously to the overall susceptibility to and patterns of windstorm damage in the BTNP. Conclusions: Directly damaged trees greatly influence the forest by causing secondary damage to other trees. We propose that directly and indirectly damaged (or susceptible) trees should be considered separately when assessing or predicting the impact of windstorms on a forest ecosystem; to better predict the pathways of community structure reorganization and guide forest management and conservation practices. Forest managers are recommended to adopt a holistic view that considers and combines various components of the forest ecosystem when establishing strategies for mitigating the impact of catastrophic winds.

• 한국환경생태학회지
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• 제10권1호
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• pp.87-102
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• 1996

한반도 난대기후대의 식생구조를 연구하기 위하여 남해안 도서지방의 상록활엽수림 지역에 52개 조사구를 설치하였다. 난대상록활엽수림은 지리적 격리와 인위적 교란에 의해 지역간 식생구조가 매우 상이하였다. 조사지의 식생들은 대체적으로 자연적 식생천이가 이루어진 상록활엽수림 집단, 장기간 훼손되었거나 관리되어온 상록활엽수림 집단, 그리고 상록활엽수종으로 천이되고 있는 조림식생 집단으로 구분되었다. 52개 조사구에서 80% 이상의 상재도를 보인 수종은 후박나무, 사스레피나무, 마삭줄, 생달나무, 광나무 등이었다. 난대기후대의 극상군락이라고 추정되는 육박나무군락은 주도와 애도에 잔존하고 있었다. 과거 교란이 있었던 해안지역에서는 구실잣밤나무로 이차천이가 예상된다.

• The Korean Journal of Ecology
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• 제21권5_3호
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• pp.589-602
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• 1998

Mt. Nam (265m), a city park of Seoul, was originally covered with a typical deciduous broad-leaved forests in Central Korea. However, the park forests have been changed the development for various purpose such as the construction of castle wall, road way, broadcasting station, theater, hotel and apartments, in addition, to thoughtless plantation or alien plant introduction. Human population growth from ca. 100 thousands persons less in that time established Seoul as the capital of choseon dynasty in 1394 to ten millions over persons at present, accelerated the vegetational changes of the park. mt. Nam boundary in those days of sunjong (1908) also was much shrinked as much the range of 300 m distance in the northern most to 700 or 800m distance in some places. The actual vegetation of Mt. Nam largely can be classified by floristic composition into two plant communities of Quercus mongolica community and Pinus densiflora community, four plantations of Pinus rigida, Robinia pseudo-acacia, Populus tomentiglandulosa and other tree species, and on mixed forest with native and alien tree species in secondary succession stage (Yim et al. 1987). The restoration movement of Mt. Nam toward to the natural condition of forest or biodiversity is moving now. However, in the movement there are some problems such as the lack of ecological consideration and the undesirable decision of priority in the practice. A warning should be given, especially, on the undesirable plantation of non-native tree species restricting the forest succession, as in the case of southern slope of Mt. Nam. First of all, the most importance in Mt. Nam management is that the restoration for natural forest and biodiversity should be carried on the basis of integrated ecological principles based on the site evaluation.

• 대한원격탐사학회지
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• 제32권1호
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• pp.1-11
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• 2016

Since forest is an important part of ecological system, the deforestation is one of global substantive issues. It is generally accepted that the climate change is related to the deforestation. The issue is worse in developing countries because the forest is one of important natural resources. In the case of North Korea, the deforestation is on the rise from forest reclamation for firewood collection and food production. Moreover, a secondary effect from flood intensifies the damage. Also, the political situation in North Korea presents difficulty to have in-situ measurements. It means that the accurate information of North Korea is nearly impossible to obtain. Thus, assessing the current situation of the forest in North Korea by indirect method is required. The objective of this study is to monitor the forest status of North Korea using multitemporal Landsat images, from 1980s to 2010s. Since the deforestation in North Korea is caused by local residents, we selected two study areas of high population density: Pyeongyang and Hyesan. In North Korea, most of clean Landsat images are acquired in fall season. The fall images have an advantage that we can easily distinguish agriculture areas from forest areas, also have an disadvantage that the forests cannot be easily identified because some of trees have turned red. To identify the forests exactly, we proposed a modified Normalized Difference Vegetation Index (mNDVI) value. The deforestation in Pyeongyang and Hyesan was analyzed by using mNDVI. The dimension of forest has decreased approximately 36% in Pyeongyang for 27 years and approximately 25% in Hyesan for 16 years. The results show that the forest areas in Pyeongyang and Hyesan have been steadily reduced.

• Current Research on Agriculture and Life Sciences
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• 제20권
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• pp.77-82
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• 2002

This study was carried out in order to produce useful material for the forest multiple use and forest protection by physico-chemical soil analysis of studied area in Sokwang-ri Forest Genetic Resource Protection Forest which was divided into in standard plots include Tricholoma matsutake and Sarcodon aspratus production forest. The result of physico-chemical soil analysis represented as following. The soil type of T. matsutake production forest was Dry brown forest soil(B1), while on the other hand the soil type of S. aspratus production forest was Moderately moist brown forest soil(B3). Between T. matsutake and S. aspratus production forest did not result in significant changes in soil pH(5.22-5.60) and soil depth(47cm), but available phosphorus, carbon, and nitrogen contents were different results. CN ratio of the fairy ring of T. matsutake was quite lower than that in S. aspratus production forests, which indicated that T. matsutake production forest was built up in the relatively immature soils which contain little organic matter. Generally, it was predicted that Pinus densiflora for. erecta forest succeeded to deciduous tree forest in stable soil environments. To conserve these T. matsutake and S. aspratus production forest, the contents of available phosphorous and exchangeable cation should be increased by continuous soil environment management and it should be established the secondary growth forests of old aged Pinus densiflora for. erecta trees as soon as possible.

• Journal of Veterinary Science
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• 제21권2호
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• pp.25.1-25.16
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• 2020

Porcine epidemic diarrhea virus (PEDV) emerged into Canada in January 2014, primarily affecting sow herds. Subsequent epidemiological analyses suggested contaminated feed was the most likely transmission pathway. The primary objective of this study was to describe general biosecurity and management practices implemented in PEDV-positive sow herds and matched control herds at the time the virus emerged. The secondary objective was to determine if any of these general biosecurity and farm management practices were important in explaining PEDV infection status from January 22, 2014 to March 1, 2014. A case herd was defined as a swine herd with clinical signs and a positive test result for PEDV. A questionnaire was used to a gather 30-day history of herd management practices, animal movements on/off site, feed management practices, semen deliveries and biosecurity practices for case (n = 8) and control (n = 12) herds, primarily located in Ontario. Data was analyzed using descriptive statistics and random forests (RFs). Case herds were larger in size than control herds. Case herds had more animal movements and non-staff movements onto the site. Also, case herds had higher quantities of pigs delivered, feed deliveries and semen deliveries on-site. The biosecurity practices of case herds were considered more rigorous based on herd management, feed deliveries, transportation and truck driver practices than control herds. The RF model found that the most important variables for predicting herd status were related to herd size and feed management variables. Nonetheless, predictive accuracy of the final RF model was 72%.

• 생명과학회지
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• 제25권6호
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• pp.646-655
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• 2015

벽방산의 산림식생에 대한 식물사회학적 연구를 수행하였다. 연구결과 벽방산은 3개 상관형의 9개 단위식생이 분포하고 있는 것으로 확인되었다. 연구지역 단위식생은 상록침엽수림의 해송-사스레피나무군락, 소나무-자금우군락, 하록활엽수림의 졸참나무-홀아비꽃대군락, 신갈나무-우산나물군락, 상수리나무군락, 소사나무군락, 굴참나무-쇠물푸레나무군락, 비목-물참대군락, 인공조림식생의 사방오리나무식재림 등으로 구분되었다. 벽방산은 지역 최고봉임에도 불구하고 산지 전역이 숲 가꾸기사업, 등산객, 조림 및 육림 등에 의해 직/간접적으로 인위적 간섭을 받고 있는 것으로 확인되었다. 연구지역 내 식생형 가운데 상대적으로 자연성이 높은 단위식생은 산지대 사면 중부에서 출현하는 졸참나무-홀아비꽃대군락, 전석지에서 확인된 비목-물참대군락 등이며, 산지능선부의 암석노출지를 중심으로 위극상의 천이계열에 해당하는 특산식물군락인 소사나무군락이 분포하고 있었다. CCA분석 결과, 각 단위식생의 발달은 해발고도, 인간간섭, 낙엽부식층, 암석노출율, 경사도 등에 영향을 받는 것으로 확인되었다. 단위식생의 종조성에 대한 집괴분석 결과로부터 벽방산 산림식생은 인위식생, 이차식생, 근자연식생으로 구분되며, 식생의 발달정도, 토지적 특성, 인위적 식재 및 관리 유무 등에 의해 삼림이 구성되고 있는 것으로 확인되었다.

• 한국환경생태학회지
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• 제32권1호
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• pp.118-131
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• 2018

주왕산국립공원의 삼림식생에 대한 식물사회학적 연구가 이루어졌다. 식물사회의 종조성과 서식처의 균질성을 강조하는 Z.-M. 학파의 방법으로 수행하였다. 52개 식생자료가 획득되었고, 출현식물 총 265분류군의 행동양식은 9계급의 변환통합우점도와 상대기여도를 통해 분석하였다. 식생자료의 모둠화 과정을 통해 단위식생을 분류하고, 그 분포와 현존균질도 등이 분석되었다. 4가지 상관우점식생 속에 9개 식물군락이 기재되었다: 신갈나무-애기감둥사초군락, 신갈나무-뱀고사리군락, 졸참나무-둥근잎천남성군락, 굴참나무-털조록싸리군락, 떡갈나무-털피나무군락, 서어나무-털대사초군락, 느티나무-등칡군락, 들메나무-개면마군락, 소나무-가는잎그늘사초군락. 삼림식생의 대상분포가 논의되었고, 표고 약 700 m가 냉온대 중부 산지대(신갈나무-생강나무아군단역)와 남부 저산지대(졸참나무-작살나무아군단역)의 전이대인 것으로 밝혀졌다. 주왕산국립공원의 삼림식생은 종조성의 낮은 균질성이 특징이었다. 결론적으로 주왕산국립공원의 삼림식생은 <지역생물기후구-대구형> 속에서 더욱 강한 대륙성 생물기후환경과 세립질 풍화토와 암편을 공급하는 유문암질 응회암 우세의 지질 환경에 대응하는 고유성이 큰 지역식생이고, 산불 영향이 더해진 근자연림 또는 이차림인 것으로 밝혀졌다.

• 한국환경생태학회지
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• 제28권6호
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• pp.725-740
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• 2014

낙남정맥 마루금 일대의 식생상황을 파악하기 위해 환경조건과 인위적 영향을 고려하여 중점조사지 6개 지역(길마재, 무량산, 여항산, 무학산, 천주산, 신어산)을 선정하여 방형구 132개소(면적 $100m^2$)를 설치하여 출현수종 및 주요 환경인자를 조사해 식생구조 특성을 분석하였다. TWINSPAN기법으로 분리된 군락은 신갈나무-굴참나무군락, 소나무-떡갈나무군락, 신갈나무-소나무군락, 편백림, 소나무-곰솔군락, 잣나무림, 철쭉재배품종-참싸리림이었다. 소나무-떡갈나무군락, 신갈나무-소나무군락, 소나무-곰솔군락은 하층에 낙엽성 참나무류의 세력이 강해 낙엽성 참나무류로의 식생천이가 예상된다. 편백림과 잣나무림, 철쭉재배품종-참싸리림은 인위적으로 조성된 인공림으로 조림수종의 우점도가 높아 당분간 현상태로 유지될 것이다. 낙남정맥의 식생은 대부분 2차림이거나 임목생산과 사방녹화를 위해 조성된 인공림이었다. 특히, 산정상부와 고지대는 대부분 신갈나무, 떡갈나무 등의 낙엽성 참나무류가 우점하거나 일부 소나무군락은 낙엽성 참나무류와의 세력경쟁을 벌이고 있었다. 반면, 저지대나 도시와 인접해 있는 지역은 곰솔, 편백, 잣나무, 철쭉재배품종 등이 식재되어 인위적인 간섭이 심한 편이었다.

• Journal of Forest and Environmental Science
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• 제32권3호
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• pp.302-310
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• 2016

The loss and degradation in tropical forest region are some of the current global concern. Hence, these issues elevated the role of rehabilitated forests in providing ecological products and services. The information on the carbon stock is important in relation to global carbon and biomass use, but lacking from the tropical region. This paper reports the assessment of tree and soil carbon stock in a chronosequence rehabilitated tropical forest stands in Malaysia. The study site was at the UPM-Mitsubishi Forest Rehabilitation Project, UPMKB. $20{\times}20m$ plot was established each and assessed in 2009 at 1-, 10- and 19-year-old sites while an adjacent ${\pm}23-year-old$ natural regenerating secondary forest plot was established for comparison. The overall total carbon stock was in the order of 19-year-old>${\pm}23-year-old$>10-year-old>1-year-old. When forest carbon stock is low, the soil component plays an important role in the carbon storage. The forest carbon recovery is crucial to increase soil carbon stock. The variations in the carbon stock showed the different stages of the forest recovery. Species survived after 19-years of planting are potential species for carbon sequestration activities in rehabilitated forest. Human intervention in rehabilitating degraded forest areas through tree planting initiatives is crucial towards recovering the forest ecological role especially in forest carbon stock capacity.