• Asian-Australasian Journal of Animal Sciences
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• 제33권6호
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• pp.1034-1041
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• 2020

Objective: The objective of this experiment was to evaluate the effect of shade allocation and shade plus fan on growth performance, dietary energy utilization and carcass characteristics of feedlot cattle under tropical ambient conditions Methods: Two trials were conducted, involving a total of 1,560 young bulls (289±22 kg BW) assigned to 24 pens (65 bulls/pen and 6 pens/treatment). Pens were 585 ㎡ with 15 m fence line feed bunks. Shade treatments (㎡ shade/animal) were: i) limited shade (LS) to 1.2 ㎡ shade/animal (LS_1.2); ii) limited shade to 2.4 ㎡ shade/animal (LS_2.4); iii) total shade (TS) which correspond to 9 ㎡/animal, and iv) total shade equipped with fans (TS+F). Trials lasted 158 and 183 days. In both studies, the average weekly maximum temperature exceeded 34℃. Results: Increasing shade allocation tended (p = 0.08) to linearly increases average daily gain (ADG), and dry matter intake (DMI, quadratic effect, p = 0.03). This effect was most apparent between LS_1.2 and LS_2.4. Shade allocation, per se, did not affect gain efficiency or estimated dietary net energy (NE). Compared with TS, TS+F increased (p<0.05) ADG, gain efficiency, and tended (p = 0.06) to increase dietary NE. There was a quadratic effect of shade on longissimus area and marbling score, with values being lower (p<0.01) for LS_2.4 than for LS_1.2 or TS. Likewise, marbling score was lower for TS+F than for TS. Percentage kidney, pelvic, and heart (KPH) linearly decreased with increasing shade. In contrast, KPH was greater for TS than for TS+F. Conclusion: Providing more than 2.4 ㎡ shade/animal will not further enhance feedlot performance. The use of fans in combination with shade increases ADG and gain efficiency beyond that of shade, alone. These enhancements were not associated with increased DMI, but rather, to an amelioration of ambient temperature humidity index on maintenance energy requirement.

• Journal of Ecology and Environment
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• 제48권3호
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• pp.374-381
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• 2024

Background: There is a wide range of phenotypic plasticity in plants that respond to tissue damage. Compensatory growth after physical damage may function as a part of tolerance to herbivory, which is affected by resource limitations and/or damage properties. Results: Under different light availability (unshaded and shaded) and damaged leaf ontogeny (control, young leaf- and mature leaf-damaged), compensatory growth was examined for the herbal vine Aristolochia contorta. Under the unshaded treatment, compensatory growth on leaf and branch emergence was strongly induced compared to the shaded treatment. Damage to young leaves induced leaf emergence more strongly than damage to old leaves. Conclusions: It appears that light availability acted as a limiting factor in the compensatory growth of A. contorta after the damage despite its vigorous growth under the shade treatment. Under the shade, leaf damage led to altered biomass allocation as indicated by a decrease in specific leaf area and an increase in root mass fraction. The present study contributes to the understanding of the phenotypic plasticity of vine species under different environmental conditions and damaged tissue, which may differ depending on the species' habitat range.

• 한국산림과학회지
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• 제86권2호
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• pp.208-213
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• 1997

산림자원 관리에 필요한 정보를 얻기 위하여 우리나라의 주요 수종인 참나무류(Quercus spp), 낙엽송(Larix leptolepis) 및 잣나무(Pinus koraiensis)에 대해 경기도 광주지방에서 수형특성, 물질분배량 및 재적 생장량을 측정하였다. 수형특성으로서는 잣나무가 수관비율 및 수관확장비가 높게 나타났으며 참나무류도 수관비율이 높게 나타나 양수임을 나타냈다. 기관별 물질분배는 줄기의 경우 밑에서 위로 갈수록 감소하였으며 이러한 감소율은 낙엽송보다 잣나무 및 참나무류가 높게 나타났다. 가지 및 엽은 세 수종 모두 정규분포 특성을 보였으나 가지보다는 엽이 더 높은 정규분포 특성을 나타내었고 수종별로는 참나무류보다 잣나무, 낙엽송이 높게 나타났다. 세 임분의 물질현존량은 낙엽송림, 잣나무림, 참나무림의 순으로 각각 171.1ton/ha, 75.3ton/ha, 61.6ton/ha로 나타났다. 이에 따라 참나무류 및 잣나무림은 초기밀도를 높여줌으로서 biomass 생산 증진뿐만 아니라 수간형질 개선을 높일 수 있을 것으로 판단된다.

• Journal of Ecology and Environment
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• 제46권3호
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• pp.243-249
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• 2022

Background: Mixed breeding herb Viola collina Besser, which produces both chasmogamous and cleistogamous flower, has limited habitats under closed canopy and short and early flowering timing, making it relatively more vulnerable to climate change. To better understand the effect of light and nutrient on the flower formation and vegetative growth of V. collina, a mesocosm experiment was conducted. Two-by-two factorial treatments of two light conditions (100% and 60% of natural light) and two fertilizer treatment conditions (fertilized and not fertilized) were applied in the mesocosm experiment. Results: The number of flowers, including chamogamous and cleistogamous flowers, was highest (5.65/pot) under 60% light and fertilized condition and lowest (1.41/pot) under 100% light and not-fertilized condition. However, above ground vegetative growth was highest (2.89 g/pot) under 100% light and fertilized condition and lowest (2.38 g/pot) under 60% light and not-fertilized condition. Above ground biomass to belowground biomass ratio was highest (1.50) under 60% light and fertilized condition and lowest (1.26) under 100% light and fertilized condition. Conclusions: This study showed that high light and nutrient are responsible for the vegetative growth, though the effect of fertilizer was reduced due to allocation and retainment of nutrients. In addition, the low light is necessary to make flowers, especially chasmogamous flowers.

• 한국토양비료학회지
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• 제44권6호
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• pp.1144-1149
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• 2011

잣나무는 우리나라의 대표적인 조림수종으로서 종자가 비산하지 못하고 조류나 설치류등의 동물에 의해 운반, 산포됨으로써 잣나무 인공조림지 주변 산림의 하층에 잣나무 치수가 천연 발생하게 된다. 조사 임분 내에서는 직경급, 수고급별 분포에서 역 J자형을 나타내는 음수의 잣나무가 상층의 참나무림에 의해 낮은 광환경과 토양의 비옥도가 낮은 조건하에서 생육하고 있다. 조사 임분은 비교적 온도가 높고 건조한 남서사면이지만 상층의 참나무림 임관에 의해 완화되며, 따라서 잣나무 종자의 발아나 치수를 보호하는 미세 입지환경을 제공 할 수 있을 것으로 생각된다. 잣나무 치수의 전체 현존량은 잣나무 인공림에 비해 높았으며 참나무림 하부의 낮은 광 환경에서도 적응하는 것으로 생각된다. 각 기관별 질소와 인의 농도는 인공 잣나무림 및 혼효하는 참나무림의 각 기관별 농도보다 낮았으며 양분량도 현존량에비해 상대적으로 적었다. 이들 양분은 일반적으로 식물의 성장에 필요한 주요 성분이므로 잣나무와 활엽수 혼효림의 시업에 있어서 지조부는 임상에 존치 시키는 것이 유리할 것으로 판단된다.

• 한국조경학회지
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• 제29권1호
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• pp.32-40
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• 2001

The purpose of designing Haebaragi park, legally designated as children park, is to make a place for children including residents performing outdoor recreation, various social interactions, and cultural activities. Design concept for space plan have twofold; the one is a positive and creative playing space and facilities for children, escaped from a monotonous playground, and the other is a cultural and social space for neighboring communities. The site having the area of 1,316.7 square meters, located in Nowon-Dong, Buk-Gu, Daegu metropolitan City, is just like a vest pocket park. The adjacent area had been developed a slum area with mixed ad visually conflicting land use patterns and low income groups. The children and residents living in the area do not have any public space suitable for playing and/or rest. After analyzing such locational characteristic as accessibility, land use of the communities, and potentials for park development, and such design concept as arrangement of facilities, efficient use of site, and functional allocation of park space, We have mad a plan for composition of spaces for various activities, provision of facilities based on estimation of user-demand and activities, and planting. In the design process, we have tried to harmonize functional spaces with facilities, and to organize all the functions as a whole. To improve urbanity and aesthetic shape of park design, we have introduced a central plaza, design of a pave floor, a torrent, large trees for shade, colonnades and so on. From this design project, we can develop the site as a children park for increasing creativities and various playing opportunities, and as a resident space for rest, cultural activities. In the future, it is required that many attempt to design and develop urban small space as a park for children and residents.

• 한국산림과학회지
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• 제86권3호
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• pp.352-364
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• 1997

자연휴양림 이용자들의 자연휴양림 시설의 이용, 자연휴양림 이용에 대한 기대 및 성취도 등을 분석하여 차후 자연휴양림의 조성은 물론 기존의 자연휴양림에 대하여 이용자들이 원하는 바를 더욱 보완하고 보다 질 좋은 자연휴양림을 조성 관리하기 위한 기초자료를 제공하고자 자연휴양림 이용자들의 시설물 이용행태와 자연휴양림 이용의 만족도를 조사분석한 바 다음과 같은 결과를 얻었다. 자연휴양림 이용자들이 휴양림내 시설물 중 화장실, 야영장, 산림욕장 등을 가장 많이 이용하였고, 가장 필요로 하는 시설물은 화장실, 매점, 급수대 등이었다. 자연휴양림의 이용 전에는 아름다운 자연풍경 감상과 피로를 풀고 휴식을 취하고자 하는 기대도가 가장 높았으며, 이용후의 성취도는 기대도와 마찬가지로 아름다운 자연풍경 감상과 피로를 풀고 휴식을 취하는데 가장 높은 성취도를 나타냈다. 자연휴양림 이용자의 만족도를 결정짓는 주요 설명변수로서, 자연휴양림 시설물의 배치 및 조화 측면에서는 청결 및 보수상태, 시설물의 유지관리, 시설물 주변 이용자들의 소음정도, 시설물 이용의 편리도, 주변의 자연경관 등이 작용하였고, 자연휴양림의 식생상태에 대한 측면에서는 주변식생의 다양도, 녹음의 양, 자연림 보호관리, 식생과 주변과의 조화 등이 만족도 결정의 주요 변수로 작용하였다. 또한 자연휴양림 시설상태에 대한 측면에서는 휴식시설, 화장실의 이용편리도 및 청결상태, 쓰레기통의 배치상태, 취사장의 이용편리도 등이 작용하였고, 자연휴양림의 운영관리실태에 대한 측면에서는 산림의 보호와 육성, 관리인의 이용자 행락지도, 휴양림에 대한 안내와 홍보수준이 만족도 결정의 주요 변수로 작용하였다.