• 제목/요약/키워드: tits

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DAGGER-SHARP TITS OCTAGONS

  • Muhlherr, Bernhard;Weiss, Richard M.
    • 대한수학회지
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    • 제58권1호
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    • pp.173-205
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    • 2021
  • The spherical buildings associated with absolutely simple algebraic groups of relative rank 2 are all Moufang polygons. Tits polygons are a more general class of geometric structures that includes Moufang polygons as a special case. Dagger-sharp Tits n-gons exist only for n = 3, 4, 6 and 8. Moufang octagons were classified by Tits. We show here that there are no dagger-sharp Tits octagons that are not Moufang. As part of the proof it is shown that the same conclusion holds for a certain class of dagger-sharp Tits quadrangles.

활엽수림에 설치한 인공새집을 이용한 박새류의 번식 생태 (Breeding Ecology of Tits Parus spp. Using Artificial Nest Boxes in a Deciduous Forest)

  • 임신재;손승훈;김규중
    • 한국산림과학회지
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    • 제100권3호
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    • pp.397-401
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    • 2011
  • 본 연구는 활엽수림 지역에 설치한 인공새집에서 번식을 실시한 박새류의 번식 생태를 파악하기 위하여 2006년부터 2010년까지의 매년 3월부터 7월까지의 기간 동안 실시되었다. 5년에 걸친 조사기간 동안 활엽수림에 설치한 인공새집에서는 곤줄박이, 쇠박새, 박새 등의 박새류가 번식을 하였다. 박새류가 번식을 실시한 인공새집은 입구직경별로 번식쌍수가 큰 차이가 없는 것으로 나타났다. 종별로는 박새가 가장 많이 이용한 것으로 나타났으며, 곤줄박이가 가장 적게 이용하였다. 인공새집을 이용한 박새류는 몸의 크기에 따라 선호하는 입구직경이 달랐는데, 몸의 크기가 큰 박새는 입구직경이 35~40 mm인 인공새집을 주로 이용하였다. 반면 몸의 크기가 가장 작은 쇠박새는 입구직경이 30 mm인 인공새집에서 주로 번식을 하였다. 첫 산란일, 한배 산란수, 한배 새끼수, 포란기간, 육추기간, 번식성공률은 종별, 연도별로 차이를 보였다. 앞으로 박새류의 번식생태에 영향을 주는 요인에 대한 연구를 통해 환경요인과 번식생태에 관한 규명이 필요할 것으로 판단된다.

Tree Species Preference and Inter-specific Difference of Foraging Maneuver, Trees and Location among Four Canopy-dwelling Birds at High-elevation Temperate Deciduous Forest in Mt. Jumbongsan

  • Park, Chan-Ryul
    • Animal cells and systems
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    • 제9권1호
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    • pp.41-46
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    • 2005
  • This study was conducted to reveal tree species preference and inter-specific difference of foraging behavior among four canopy-dwelling birds at forest dominated by Quercus mongolica, Acer pseudosieboldian and Carpinus cordata at 1,000 meters above sea level during breeding season of birds from 1995 to 1997 in Mt. Jumbongsan. Breeding birds were about 25 species and dominant birds were Erithacus cyane, Parus ater and Parus palustris. A relatively high number of bush-nesters can be a characteristic of breeding bird community at study area. Three gleaners (Tits, P. varius, P. palustris and P. ater) selectively preferred the trees irrespective of dominant tree species, whereas bark foragers (Nuthatch, Sitta europaea) utilized the dominant trees. The four birds showed significant inter-specific difference in use of foraging location, but the three tits did not show significant inter-specific difference in use of foraging maneuver and trees. Closely related tits may coexist with each other by inter-specific different use of foraging location determined by foliage structure and leaf arrangement.

침엽수림과 활엽수림 지역에서 박새류의 입공새집 이용 (Use of Artificial Nest Boxes of Tits in Coniferous and Deciduous Forests)

  • 임신재;손승훈;김민진;강정훈
    • 한국산림과학회지
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    • 제97권1호
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    • pp.83-87
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    • 2008
  • 본 연구는 침엽수림 지역과 활엽수림 지역에서 박새류의 인공새집 이용 특성을 파악하기 위해 각각 2006년과 2007년 3월에서 6월까지의 기간 동안 실시되었다. 두 지역에 생육하고 있는 수목의 종수, 종다양도지수, 흉고단면적은 침엽수림 지역에 비해 활엽수림 지역에서 높은 것으로 나타났다. 또한 엽층의 수직분포에 있어서도 지면에서 1m 이하의 엽층을 제외한 모든 엽층의 피도량이 활엽수림 지역에서 높은 것으로 나타났다. 2년에 걸쳐 두 지역에 설치한 인공새집에서는 곤줄박이, 쇠박새, 진박새, 박새가 번식을 한 것으로 나타났다. 침엽수림 지역보다 활엽수림 지역에서 번식쌍수가 더 높았다. 진박새의 경우, 한배산란수와 한배새끼수, 번식성공률이 침엽수림 지역에서 높은 것으로 나타났다. 또한 박새는 한배새끼수와 번식성공률이 활엽수림 지역에서 더 높았다. 서식 환경 구조 및 박새류의 종간 니치(niche)에 따라 선호하는 서식지가 다른 것으로 판단된다. 다양한 서식 환경에 설치한 인공새집이 조류 군집 및 생태에 미치는 영향을 지속적으로 파악해야 할 것이며, 이를 통해 장기적으로 인공새집을 설치 및 관리해야 할 것으로 판단된다.

Differences in Artificial Nest Boxes Use of Tits Between Deciduous and Coniferous Forests

  • Rhim, Shin-Jae;Lee, Ju-Young
    • 한국산림과학회지
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    • 제94권5호통권162호
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    • pp.338-341
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    • 2005
  • This study was conducted to describe the differences in artificial nest boxes use of tits between deciduous and coniferous forests at 2nd campus of Chung-Ang University ($37^{\circ}00^{\prime}04^{{\prime}{\prime}}N$, $127^{\circ}13^{\prime}96^{{\prime}{\prime}}E$), Ansung, Korea from January to August 2005. Tree species richness, tree species diversity index (H') and total basal areas were higher in deciduous forest than in coniferous forest. High, middle, low and understory canopy layers were more developed in deciduous forest, except the coverage of bush-ground layer. Varied tit Parus varius, marsh tit P. palustris and great tit P. major used the artificial nest boxes in this study. Number of breeding pairs of tits used artificial nest boxes, clutch size, and weight and size of eggs were higher in deciduous forest than in coniferous forest. The differences in habitat structure between study sites are very likely to have influenced how breeding birds used the available habitat. Artificial nest boxes could be used as management and conservation tool for birds, particularly in areas, where the availability of natural cavities and coverage of higher layer are limited.

도시녹지에서 박새의 번식특성에 관한 연구 (A Research on the Reproductive Properties of Great Tits in the Urban Forests)

  • 정혜진;조은아;고현서;장갑수
    • 한국환경복원기술학회지
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    • 제15권5호
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    • pp.155-163
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    • 2012
  • This study was carried out to monitor reproductive responses of great tits in 17 urban forests in Daegu metropolitan city. The reproductive perspectives of great tits were surveyed by using 106 artificial bird nests, of which five or seven nests were set up in every urban forest. A ratio of artificial nests used by great tits for their reproduction was 27.4%. It was showing that forests, where the reproductive response was higher, was located at the edge of the city, or was known as having a good vegetation structure in the urban area. The laying date of a great tit was a little earlier in forests in the middle of the city. It might be dependent on the density of artificial land uses including a residential area and an industrial complex, which are able to increase an urban micro-temperature. Otherwise, natural forests or forest patches nearby natural forests located at the edge of the city were showing that the laying date of great tits was relatively later than the oneee in the forest in the middle of the city. There was a big difference of reproduction perspectives of great tit between the 1st and 2nd reproduction. In the 1st reproduction, a clutch size was larger, while an egg volume was so low. Otherwise, the clutch size was shown so smaller in the 2nd reproduction than in the 1st reproduction, while the egg volume was larger in the 2nd reproduction. It might be due to the survival strategy of a great tit to prepare the winter season for a juvenile. Many variables, regarding to the problem of climate changes, have been linked to the environment of urban area and the bird habitats. Finally, Monitoring a bird reproduction is a valuable work for managing an urban forest as well as for conserving a natural forest.

Vertical Distribution of Foraging Tits in Mixed Species Flocks in Urban Forests

  • Lee, Sang-Don
    • The Korean Journal of Ecology
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    • 제22권2호
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    • pp.65-68
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    • 1999
  • In December-January of 1996-1997 and 1997-1998, information was gathered about vertical distribution of foraging sites of tits in 34 flocks in coniferous and deciduous forests. There was a significant effect of forest type on the distribution of foraging sites of each species. Habitat was classified into 5 height layers vertically: ground, bushes (usually<1.5 m, up to 3 m), tree layer 1 (up to 1/3 of tree height), tree layer 2 (1/3-2/3 tree height). and tree layer 3 (>2/3 tree height). There were differences among species: great tit (Parus major) foraged mostly on the ground, coal tit (P. ater) and long-tailed tit (Acrocephalus caudatus) - on the highest tree layer, marsh tit (P. palustris) was often seen on bushes, and varied tit (P. varius) - in tree layer 2. Smaller species used upper and outer parts of trees. suggesting that, like in most other similar studies. larger dominant species prevented smaller species from using inner parts of trees.

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Reproductive Strategies in Great Tits

  • Yoo, Jeong-chil
    • 한국동물학회:학술대회논문집
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    • 한국동물학회 1995년도 제16회 생물과학 심포지움 강연록
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    • pp.68-73
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    • 1995
  • Most female Great Tits lay one egg each day until the clutch is complete. However, some exceptions are found. “Pause day/s” most frequently occur after the 1st egg is laid. In general, egg-size increase with laying sequence, but there is year-to-year variation. The relationship between egg size and laying sequence is found more significantly in relatively larger clutches than in smaller ones. Great Tits tend to advance the hatching of their chicks by starting to incubate earlier in relation to clutch completion as the breeding season progresses. hatching asynchrony affects chick´s growth rate, but when the effect of laying date on hatching asynchrony is controlled, the effect of hatching asynchrony on growth rate is not found. These findings support the ´hurry-up´ hypothesis.

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통계모형을 활용한 박새류의 서식지 연결성 평가: 서울시 도시생태현황도 자료를 중심으로 (Habitat Connectivity Assessment of Tits Using a Statistical Modeling: Focused on Biotop Map of Seoul, South Korea)

  • 송원경;김은영;이동근
    • 환경영향평가
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    • 제22권3호
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    • pp.219-230
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    • 2013
  • Species distribution modeling is one of the most effective habitat analysis methods for wildlife conservation. This study was for evaluating the suitability of species distribution to distance between forest patches in Seoul city using tits. We analyzed the distribution of the four species of tits: varied tit (Parus varius), marsh tit (P. palustris), great tit (P. major) and coal tit (P. ater), using the landscape indexes and connectivity indexes, and compared the resulting suitability indexes from 100m to 1,000m. As factors affecting to the distribution of tits, we calculated landscape indices by separating them into intra-patch indices (i.e. logged patch area (PA), area-weighted mean patch shape index (PSI), tree rate (TR)) and inter-patch indices (i.e. patch degree (PD), patch betweenness (PB), difference probability of connectivity (DPC)), to analyze the internal properties of the patches and their connectivity by tits occurrence data using logistic regression modeling. The models were evaluated by AICc (Akaike Information Criteria with a correction for finite sample sizes) and AUC (Area Under Curve of ROC). The results of AICc and AUC showed DPC, PA, PSI, and TR were important factors of the habitat models for great tit and marsh tit at the level of distance 500~800m. In contrast, habitat models for coal tit and varied tit, which are known as forest interior species, reflected PA, PSI, and TR as intra-patch indices rather than connectivity. These mean that coal tit and varied tit are more likely to find a large circular forest patch than a small and long-shaped forest patch, which are higher rate of forest. Therefore, different strategies are required in order to enhance the habitats of the forest birds, tits, in a region that has fragmented forest patches such as Seoul city. It is important to manage forest interior areas for coal tit and varied tit, which are known as forest interior species and to manage not only forest interior areas but also connectivity of the forest patches in the threshold distance for great tit and marsh tit as adapted species to the urban ecosystem for sustainable ecosystem management.

Nest Box Preference by Secondary Cavity-Nesting Birds in Forested Environments

  • Choi, Chang-Yong;Nam, Hyun-Young;Lee, Eun-Jae;Chung, Ok-Sik;Park, Yong-Su;Lee, Jong-Koo;Hyun, Jee-Yun;Lee, Woo-Shin
    • Journal of Ecology and Environment
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    • 제30권1호
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    • pp.49-56
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    • 2007
  • We placed and monitored 2,137 nest boxes to determine how the size of the entrance hole and the box placement influenced nest box selection by secondary cavity-nesting birds and to derive recommendations for the use of nest boxes for management of cavity-nesting birds in forested environments. A total of 566 pairs of seven bird species used the nest boxes from 1997 to 2006, 562 of which were secondary cavity-nesters. Sympatric tits such as varied tits (Parus varius), great tits (P. major), and marsh tits (P. palustris) were common breeding birds in nest boxes, and showed clear preferences for 4.0 cm, 3.5 cm and 3.0 cm nest holes, respectively. Tree sparrows (Passer montanus) and Eurasian nuthatches (Sitta europaea) preferred 4 cm and 3.5 cm holes, respectively. We did not detect selection for the directional orientation for the entrance hole, but the birds appeared to avoid nest boxes that faced steep or gentle upward slopes and those less than 1.8 m from the ground. These results are probably related to avoidance of disturbance and predation. We suggest that diverse species can be supported by the placement of nest boxes with entrance holes of various sizes and that specific species can be targeted by selecting the hole sizes preferred by those species. To attract secondary cavity-nesters, managers should avoid placing nest boxes close to the ground and facing hills. This study also suggests that careful selection and placement of nest boxes is needed to avoid biases in research using nest boxes.