Association of dominated tree species in lowland tropical forest of Tangkoko Nature Reserve, Bitung, North Sulawesi

Studies were carried out at two 'salt-licks' in lowland tropical forest on North Sulawesi, Indonesia. During 60 days of observation 586 sightings of babirusa were made, comprising 161 adult males, 155 adult females, 11 adults of unknown sex, 78 subadult males, 53 subadult females and 34 subadults of indeterminate sex; juveniles were observed 94 times, 19 males, 12 females and 63 of unknown sex. We saw 226 groups ranging in size from one to eight animals (median = 2). Almost half the sightings were of solitary animals, usually adult males. Bachelor groups of four or more babirusa were never seen. Adult females were rarely seen without company, often both juveniles and subadults being sighted together with them. There were never more than three adult females in a group. There were about twice as many family groups without adult males as there were with males. Agonistic behaviour between males was confined to 'threat at a distance', 'nose in the air', 'head under jaw submission' and 'front half supported' behaviours. Incidents of female-female agonistic behaviour were fewer, but in two, the dominant female chased her inferior off the 'salt-lick'.

Download Full-text

Nutrients limit photosynthesis in seedlings of a lowland tropical forest tree species

Oecologia ◽

10.1007/s00442-011-2099-5 ◽

2011 ◽

Vol 168 (2) ◽

pp. 311-319 ◽

Cited By ~ 51

Author(s):

S. C. Pasquini ◽

L. S. Santiago

Keyword(s):

Tropical Forest ◽

Tree Species ◽

Forest Tree ◽

Lowland Tropical Forest ◽

Forest Tree Species

Download Full-text

Heterospecific and conspecific associations of trees in lowland tropical forest of New Guinea

Biodiversitas Journal of Biological Diversity ◽

10.13057/biodiv/d210960 ◽

2020 ◽

Vol 21 (9) ◽

Author(s):

Agustinus Murdjoko ◽

MARTHEN MATHIAS JITMAU ◽

DONY ARISTONE DJITMAU ◽

RIMA HERLINA SETIAWATI SIBURIAN ◽

ANTONI UNGIRWALU ◽

...

Keyword(s):

Tropical Forest ◽

Tropical Forests ◽

Plant Communities ◽

Correspondence Analysis ◽

Canonical Correspondence Analysis ◽

Tree Species ◽

Tropical Rainforest ◽

New Guinea ◽

Lowland Tropical Forest ◽

Study Sites

Abstract. Murdjoko A, Jitmau MM, Djitmau DA, Siburian RHS, Ungirwalu A, Wanma AO, Mardiyadi Z, Rumatora A, Mofu WY, Sineri AS, Fatem SM, Worabai D, May NL, Tokede MJ, Warmetan H, Wanggai CB, Wanma JF, Sirami EV, Paembonan JB, Unenor E, Kuswandi R, Lekitoo K, Khayati L, Benu NMH, Tambing J, Saragih ASB. 2020. Heterospecific and conspecific associations of trees in lowland tropical forest of New Guinea. Biodiversitas 21: 4405-4418. The vegetation in the tropical rainforest of New Guinea consists of a large number of species that interact with each other within and among species. While several studies have attempted to reveal the diversity of flora of New Guinea, little is known about plant communities that develop associations. This study aimed to investigate the associations of tree species in lowland tropical forest in New Guinea. The associations depicted in this study were in the form of conspecific associations (among small and large individuals within same species) and heterospecific (among individuals of different species and divided into under and upper story). We established 48 rectangular plots created in Murkim and Teiraplu as part of Pegunungan Bintang Regency, Papua Province. Canonical correspondence analysis (CCA) was used to analyze heterospecific and conspecific associations. The results showed that the understory and upper story vegetation had different patterns of heterospecific association. The understory configured three heterospecific associations, consisting of 5, 13, and 90 species, while the upper story formed four heterospecific associations with 4, 8, 11, and 63 species. The analysis of conspecific associations showed of 149 tree species recorded in the study sites, only 66 species that had both small and large individuals, displaying the pattern of conspecific association. Among them, 41 species had positive associations while 25 species had negative associations. Our findings enrich the knowledge in theoretical ecology of tropical forests, especially in New Guinea.

Download Full-text

Canopy closure and the distribution of tropical forest tree species at La Selva, Costa Rica

Journal of Tropical Ecology ◽

10.1017/s0266467400008609 ◽

1995 ◽

Vol 11 (2) ◽

pp. 161-177 ◽

Cited By ~ 76

Author(s):

Milton Lieberman ◽

Diana Lieberman ◽

Rodolfo Peralta ◽

Gary S. Hartshorn

Keyword(s):

Costa Rica ◽

Tropical Forest ◽

Tree Species ◽

Great Majority ◽

Forest Tree ◽

Tree Size ◽

Canopy Closure ◽

Lowland Tropical Forest ◽

La Selva ◽

Phase Dynamics

ABSTRACTAn index of canopy closure was used to estimate closure above the crowns of all trees ≥ 10 cm dbh in 11.11 ha of undisturbed lowland tropical forest at La Selva, Costa Rica. To correct for the efFects of tree size on canopy closure, we used the residual of the regression of the canopy closure index on tree size. Analyses were carried out for the 104 species which had ≥ individuals; a total of 3224 trees were included. Nine species were found to have their crowns in significantly more open conditions than expected by chance and five species were found to have their crowns in significantly more closed conditions than expected by chance (P < 0.05). The remaining 90 species (86.5% of the assemblage) were distributed at random with respect to canopy closure, occupying the available light conditions indiscriminately. Species occurring under higher light levels did not show a narrower range of tolerance than did other species. Most species were found to occur over a substantial proportion of the canopy closure continuum present in the stand; overlap among the great majority of species in the assemblage is extensive. The results support the view that tropical forests comprise assemblages of generalist tree species, and raise questions about the classic notions of gap-phase dynamics.

Download Full-text