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1.
Zoology (Jena) ; 114(2): 69-77, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21435853

RESUMO

Postnatal changes in flight development, wing shape and wing bone lengths of 56 marked neonate Hipposideros pomona were investigated under natural conditions in southwest China. Flight experiments showed that pups began to flutter with a short horizontal displacement at 10 days and first took flight at 19 days, with most achieving sustained flight at 1 month old. Analysis of covariance on wingspan, wing area, and the other seven wing characteristics between 'pre-flight' and 'post-volancy' periods supports the hypothesis that growth had one 'pre-flight' trajectory and a different 'post-volancy' trajectory in bats. Wingspan, handwing length and area, armwing length and area, and total wing area increased linearly until the age of first flight, after which the growth rates decreased (all P < 0.001). Wing loading declined linearly until day 19 before ultimately decreasing to adult levels (P < 0.001). Additionally, the relationship of different pairwise combinations of bony components composing span-wise length and chord-wise length was evaluated to test the hypothesis that compensatory growth of wing bones in H. pomona occurred in both 'pre-flight' and 'post-volancy' periods. The frequency of short-long and long-short pairs was significantly greater than that of short-short, long-long pairs in most pairs of bone elements in adults. The results indicate that a bone 'shorter than expected' would be compensated by a bone or bones 'longer than expected', suggesting compensatory growth in H. pomona. The pairwise comparisons conducted in adults were also performed in young bats during 'pre-flight' and 'post-volancy' periods, demonstrating that compensatory growth occurred throughout postnatal ontogeny.


Assuntos
Osso e Ossos/anatomia & histologia , Quirópteros/anatomia & histologia , Quirópteros/crescimento & desenvolvimento , Asas de Animais/anatomia & histologia , Asas de Animais/crescimento & desenvolvimento , Animais , Desenvolvimento Ósseo , China , Quirópteros/fisiologia , Feminino , Voo Animal , Masculino
2.
Ying Yong Sheng Tai Xue Bao ; 19(8): 1775-81, 2008 Aug.
Artigo em Chinês | MEDLINE | ID: mdl-18975757

RESUMO

With spatially explicit landscape model (LANDIS), the dynamic change of forest landscape in Youhao Forest Bureau in Xiaoxinganling Mountains from 2001-2201 under 5 planting proportions of coniferous and broadleaved species, i.e., 100% broadleaved species, 70% broadleaved and 30% coniferous species, 50% broadleaved and 50% coniferous species, 30% broadleaved and 70% coniferous species, and 100% coniferous species, was studied, taking the forest under natural regeneration after harvesting as the control. The results showed that afforestation effectively promoted the recovery of forest resources, but single planting of coniferous species would lead to the area percent of broadleaved species lower than the control. When broadleaved species were planted only, the area percent of coniferous species was lower than the control. The area percent and aggregation index of Pinus koraiensis and Larix gmelini increased with increasing planting proportion of coniferous species, and those of Quercus mongolica increased with increasing planting proportion of broad-leaved species. Afforestation decreased the area percent of Betula phatyphylla, but had no significant effects on its aggregation index. Different afforestation strategies not only altered the species area percent, but also affected the species spatial pattern.


Assuntos
Conservação dos Recursos Naturais , Quercus/crescimento & desenvolvimento , Traqueófitas/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Biodiversidade , China
3.
Ying Yong Sheng Tai Xue Bao ; 19(5): 949-55, 2008 May.
Artigo em Chinês | MEDLINE | ID: mdl-18655576

RESUMO

A spatially explicit landscape model LANDIS was applied to simulate the forest landscape changes under four management alternatives (no cutting, clear cutting, selective cutting I and II) in Youhao Forestry Bureau located in Small Xing' an Mountain from 2000 to 2200. The outcomes from LANDIS were combined with a landscape-level habitat suitability index (HSI) model in a GIS environment to assess Sciurus vulgaris habitat quality. The results showed that the increase of suitable habitat area and the decrease of marginally suitable area were the fastest under no cutting scenario, and the slowest under clear cutting scenario. Suitable habitat area increased faster while marginally suitable area decreased more slowly under selective cutting I scenario than under selective cutting II. Overall, the optimal management alternative of S. vulgaris habitat was in the sequence of no cutting, selective cutting I, selective cutting II, and clear cutting.


Assuntos
Ecossistema , Agricultura Florestal/métodos , Sciuridae/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Animais , Modelos Teóricos
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