Modelling the management of fragmented forests: Is it possible to recover the original tree composition?

We studied changes in germination rates and dispersal distance of seeds of Ficus perforata and F. lundelli dispersed by howler monkeys (Alouatta palliata mexicana), in a small (40 ha) ‘disturbed’ and a larger (>600 ha) ‘preserved’ tropical rainforest in southern Veracruz, Mexico. The interaction between A. p. mexicana and Ficus (Urostigma) spp. is beneficial for the interacting species and has important implications for their conservation. Howler monkeys gain from the ingestion of an important food source, germination rates of Ficus seeds are improved by passage through the monkeys' digestive tract, and the seeds are more likely to be deposited in a site suitable for germination and development. Seed dispersal distances are relatively larger in the preserved site, with both the size of the forest area and the spatial pattern of Ficus affecting the dispersal process. In a large forest fragment with ‘regularly’ distributed Ficus individuals the howler monkeys move away from the seed source, increasing the probability that the seeds are desposited on a tree other than Ficus, which is important for the germination and future development of a hemiepiphytic species. In a small forest fragment with trees distributed in clumps howlers repeatedly use the same individual trees, and faeces containing seeds may be dropped on unsuitable trees more often. These are key issues when addressing conservation policies for fragmented forests.

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Diversity, Abundance, Species Composition and Similarity of Genus Xanthopimpla (Ichneumonidae: Pimplinae) in Logged and Fragmented Forests of the Langat Basin in Selangor, Malaysia

Journal of Asia-Pacific Entomology ◽

10.1016/s1226-8615(08)60168-5 ◽

2003 ◽

Vol 6 (1) ◽

pp. 55-62 ◽

Cited By ~ 4

Author(s):

A.B. Idris ◽

J. Hanidah ◽

A.D. Gonzaga ◽

A. Nur Azura

Keyword(s):

Species Composition ◽

Fragmented Forests

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Changes in Woody Vegetation over 31 Years in Farmed Parkland of the Central Plateau, Burkina Faso

Land ◽

10.3390/land10050470 ◽

2021 ◽

Vol 10 (5) ◽

pp. 470

Author(s):

Koichi Takenaka ◽

Kenta Ikazaki ◽

Saïdou Simporé ◽

François Kaboré ◽

Natacha Thiombiano ◽

...

Keyword(s):

Burkina Faso ◽

Eucalyptus Camaldulensis ◽

Woody Vegetation ◽

Importance Value Index ◽

Importance Value ◽

Central Plateau ◽

West Region ◽

Sapling Survival ◽

Tree Composition ◽

Insight Into

Farmed parklands of the Central Plateau, Burkina Faso, integrate native woody vegetation with managed cropland. However, sapling survival in the parklands is increasingly threatened. This study characterized woody vegetation abundance along a 2.7 km long transect in the Doulou Basin, Boulkiemdé Province, Central West Region, to assess changes in vegetation composition since 1984. In addition, a householder survey was conducted to gain insight into tree uses and preferences and residents’ knowledge of regulations. In total, 4999 individuals from 26 tree species were recorded, including 123 individuals (11 species) with stem DBH ≥ 5 cm, and 4876 individuals (21 species) with stem DBH < 5 cm. The three species with the highest importance value index provided fruit for sale or self-consumption. Tree abundance was associated with soil type and topography; highest abundance was on Lixisol soils along the lower transect. Soil degradation and preference changes among residents since 1984 may have influenced tree abundance. Certain beneficial species (e.g., Vitellaria paradoxa) have declined in abundance, and certain exotics (Azadirachta indica and Eucalyptus camaldulensis) have expanded in distribution. Respondents expressed strongest interest in three species, including V. paradoxa, that show high versatility. These results supported the recorded tree composition. The respondents generally understood forest conservation regulations. Dissemination of regreening technology and awareness promotion among residents is essential for sustainable tree use in farmed parklands.

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The ecology of terricolous lichens of the Northern Conifer – Hardwood forests of central Eastern Canada

Canadian Journal of Botany ◽

10.1139/b68-138 ◽

1968 ◽

Vol 46 (8) ◽

pp. 1043-1078 ◽

Cited By ~ 15

Author(s):

J. D. H. Lambert ◽

P. F. Maycock

Keyword(s):

Environmental Conditions ◽

Ground Level ◽

Hardwood Forests ◽

Deciduous Tree ◽

Eastern Canada ◽

Central Canada ◽

Terricolous Lichens ◽

Moisture Conditions ◽

Tree Composition ◽

Lichen Growth

A quantitative analysis of the terricolous (ground) lichens in the Northern Conifer – Hardwood forests of central Canada is presented. Seventy-one forest stands were sampled to determine the composition of the tree and lichen strata. Tree composition was expressed in terms of a series of importance values determined from measures of frequency, density, and dominance on a relative basis, with the importance values for all trees in a stand totalling 300. A statistical analysis of lichen distribution showed that while lichens reacted in a similar manner to moisture conditions as the trees they were more commonly found in stands on dry sites. An ordination of stands indicated that optimum environmental conditions for lichen growth were found in dry young conifer stands of low absolute dominance with fairly open canopies, with slowly decomposing ground litter of decidedly acidic reaction.The increase of deciduous tree species in the mesic segments of the moisture gradient produced environmental conditions unsuitable for most of the lichen species recorded. The reduced occurrence of lichens in such sites was interpreted as being related to the lack of suitable substrates, reduction in light intensity at ground level, increased litter, and a more rapid turnover of organic matter.

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CORRIDORS AND EDGES IN RELATION TO FRAGMENTED FORESTS

Eastern Deciduous Forest ◽

10.5749/j.ctttsrbh.11 ◽

2000 ◽

pp. 131-154

Keyword(s):

Fragmented Forests

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Influence of historical and contemporary habitat changes on the population genetics of the endemic South African parrot Poicephalus robustus

Bird Conservation International ◽

10.1017/s0959270919000315 ◽

2019 ◽

Vol 30 (2) ◽

pp. 236-259

Author(s):

WILLEM G. COETZER ◽

COLLEEN T. DOWNS ◽

MIKE R. PERRIN ◽

SANDI WILLOWS-MUNRO

Keyword(s):

Climate Change ◽

South Africa ◽

Spatial Scales ◽

Population Decline ◽

Source Population ◽

Population Bottlenecks ◽

Eastern Cape ◽

Forest Patches ◽

In The Wild ◽

Fragmented Forests

SummaryThe Cape Parrot Poicephalus robustus is a habitat specialist, restricted to forest patches in the Eastern Cape (EC), KwaZulu-Natal (KZN) and Limpopo provinces of South Africa. Recent census estimates suggest that there are less than 1,600 parrots left in the wild, although historical data suggest that the species was once more numerous. Fragmentation of the forest biome is strongly linked to climate change and exploitation of the forest by the timber industry. We examine the subpopulation structure and connectivity between fragmented populations across the distribution of the species. Differences in historical and contemporary genetic structure of Cape Parrots is examined by including both modern samples, collected from 1951 to 2014, and historical samples, collected from 1870 to 1946. A total of 114 individuals (historical = 29; contemporary = 85) were genotyped using 16 microsatellite loci. We tested for evidence of partitioning of genotypes at both a temporal and spatial scales by comparing shifts in allelic frequencies of historical (1870–1946) and contemporary (1951–2014) samples across the distribution of the species. Tests for population bottlenecks were also conducted to determine if anthropogenic causes are the main driver of population decline in this species. Analyses identified three geographically correlated genetic clusters. A southern group restricted to forest patches in the EC, a central group including birds from KZN and a genetically distinct northern Limpopo cluster. Results suggest that Cape Parrots have experienced at least two population bottlenecks. An ancient decline during the mid-Holocene (∼ 1,800-3,000 years before present) linked to climate change, and a more recent bottleneck, associated with logging of forests during the early 1900s. This study highlights the effects of climate change and human activities on an endangered species associated with the naturally fragmented forests of eastern South Africa. These results will aid conservation authorities with the planning and implementation of future conservation initiatives. In particular, this study emphasises the Eastern Cape mistbelt forests as an important source population for the species and calls for stronger conservation of forest patches in South Africa to promote connectivity of forest taxa.

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