Montane Evergreen Forest Research Articles

Montane evergreen forest deforestation for banana plantations decreased soil organic carbon and total nitrogen stores to alarming levels

Forest conversion to agricultural land has been shown to deplete soil organic carbon (SOC) and soil total nitrogen (STN) stocks. However, research on how soil properties respond to forest conversion to shifting cultivation has produced conflicting results. The conflicting findings suggest that the agricultural system may influence the response of SOC and STN to forest conversion to agriculture, depending on the presence of vegetative cover throughout the year. Due to the unique characteristics of montane evergreen forests (MEF) and banana plantations (BP), SOC and STN response to MEF conversion to BP may differ from existing models. Nevertheless, research on how soil properties are affected by MEF conversion to BP is scarce globally. In order to fill this research gap, the goal of this study was to evaluate how much deforestation for BP affects SOC, STN, and soil quality by analysing these soil parameters in MEF and BP fields down to 1-m depth, using standard profile-based procedures. Contrary to the specified hypothesis that SOC and STN losses would be restricted to the upper 20-cm soil layer, SOC losses were extended to the 40-cm depth layer and STN losses to the 60-cm depth layer. The soils lost 18.56 Mg ha – 1 (37%) of SOC from the upper 20 cm and 33.15 Mg ha – 1 (37%) from the upper 40 cm, following MEF conversion to BP. In terms of STN, the upper 20, 40, and 60 cm lost 2.98 (43%), 6.62 (47%), and 8.30 Mg ha – 1 (44%), respectively. Following MEF conversion to BP, the SOC stratification ratio decreased by 49%, implying a decline in soil quality. Massive exportation of nutrients, reduced C inputs due to complete removal of the arboreal component and crop residues, the erodibility of the soils on the study area’s steep hillslopes, and the potential for banana plantations to increase throughfall kinetic energy, and splash erosion through canopy dripping are thought to be the leading causes of SOC and STN losses. More research is needed to identify the extent to which each cause influences SOC and STN losses.

Floristic composition and plant community distribution along environmental gradients in Guard dry Afromontane forest of Northwestern Ethiopia

BackgroundDry evergreen montane forests of Ethiopia provide economic and ecological services for the community but it is under several threats of natural and anthropogenic disturbances. The study aimed to investigate the floristic composition, species diversity, and plant community distribution of Guard forest along environmental gradients.MethodsA systematic sampling technique was used to collect vegetation and environmental data. Fifty eight plots each with 400 m2 (20 m X 20 m) were established for trees and shrubs and 2 m x2m (4 m2) for herbs along eleven transect lines. Shannon Weiner diversity index and evenness were used to assess the species diversity and richness. The similarities among plant communities were computed using Sorenson’s similarity index. The plant community types and vegetation-environment relationships were analyzed using hierarchical cluster analysis and Canonical correspondence analysis (CCA) in R software, respectively.ResultsA total of 137 plant species belonging to 111 genera and 55 families were identified. The most dominant families in the study area were Fabaceae and Asteraceae. Among the total plant species documented in the forest, 42(30.65%) were trees, 36 (26.28%) were shrubs, 48(35.04%) were herbs, and 11 (8.03%) were climbers. Of the total species, 14(10.22%) species are endemic to Ethiopia and Eritrea. Three plant community types were identified by cluster analysis. The Shannon-Weiner Diversity Index was 3.39 and evenness was 0.87 for the forest. The pattern of plant species distribution was significantly influenced by altitude, pH, BD, slope, and charcoal (P < 0.05).ConclusionGuard forest has good species diversity and richness, and supports different endemic plant species that show the potential of the area to support useful but some of the characteristics species are not found in the forest and others are rare in their existence due to the presence of disturbances and need immediate conservation to ensure sustainable use and management of the forest.

Structural diversity is a key driver of above-ground biomass in tropical forests

ABSTRACT Background A gamut of abiotic and biotic factors is related to the amount of above-ground biomass (AGB) produced in ecosystems. Some factors have direct and others indirect relationships with AGB. Detailed analyses in tropical forests are few but much needed for better understanding the potential impacts of global change drivers and for mitigating impacts. Aims Here, we examined the relationship between AGB and different predictor variables and quantitatively evaluated their relative importance in lowland to lower montane deciduous and lower montane – montane evergreen forest types. We hypothesised that the relationship between AGB and climate, topography, structural diversity, species diversity (alpha and beta) and phylogenetic diversity would differ between the two forest types. Methods We inventoried trees from 114 plots (each 0.1 ha) and used partial least square structural equation modelling to test the direct and indirect relationship between AGB and the predictor variables. Results We found that structural diversity variables, stem density and tree girth, were significantly and positively related to AGB in both forest types, displaying a stronger relationship in montane evergreen forests (w = 0.65 for density and 0.89 for tree girth). In the deciduous forest, alpha and phylogenetic diversity were also important factors, whereas beta and phylogenetic diversity were important in the evergreen forest. The effects of topography and climate varied between forest types, with elevation and precipitation being related to AGB directly and indirectly through their relationship with structural diversity. Conclusion Our results suggest that structural diversity is a key driver of tropical forest biomass, both directly and indirectly. This fundamental understanding can aid in the predictive efforts of biodiversity conservation and forest management.

Southbound - the southernmost record of Tylototriton (Amphibia, Caudata, Salamandridae) from the Central Highlands of Vietnam represents a new species.

A new species of the genus Tylototriton is described from Ngoc Linh Mountain, Kon Tum Province, in the Central Highlands of Vietnam based on integrative taxonomy, namely by combining molecular and morphological evidence. Tylototritonngoclinhensissp. nov. differs from all other congeners based on morphological data, allopatric distribution, and molecular divergence. In terms of genetic divergence, Tylototritonngoclinhensissp. nov. distinctly differs from the sister species T.panhai (6.77%) and from T.ngarsuensis (12.36%) based on the mitochondrial NADH dehydrogenase subunit 2 (ND2) gene. Tylototritonngoclinhensissp. nov. is a moderate sized and robust salamander species with large cephalic edges, parotoids, and vertebral ridge orange in coloration. The new taxon differs from its congeners by a combination of the following morphological characteristics: size medium (SVL 60.8-66.5 mm, TL 57.6-61.8 mm in males, and SVL 72.5-75.6 mm, TL 62.9-67.9 mm in females); head longer than wide; parotoids very prominent and enlarged, projecting backwards; tail length shorter than snout-vent length; vertebral ridge large, high and glandular in appearance; 14 large and distinct dorsolateral glandular warts; gular fold present; tips of fore and hind limbs overlapping when adpressed along the body; tips of fingers reaching between eye and nostril when foreleg is laid forward; dorsal surface and lateral sides of the head, upper and lower lips, dorsolateral glandular warts, vertebral ridge, the peripheral area of the cloaca and the ventral edge of the tail orange in coloration; the presence of a distinct black line extending from the posterior end of the eye towards the shoulder. Tylototritonngoclinhensissp. nov. is restricted to evergreen montane forests near water bodies on Ngoc Linh Mountain. We suggest that the new species should be classified as Endangered (EN) in the IUCN Red List. This new important discovery represents the eighth Tylototriton taxon described from Vietnam, and at the same time constitutes the southernmost distributional record for the whole genus in Asia.

FOREST ECOSYSTEM SERVICES AND THEIR VALUATION IN MIZORAM, THE EASTERN EXTENSION OF THE HIMALAYA

This paper examines forest ecosystem services and their valuation in Mizoram, the eastern extension of the Himalaya. This study was conducted by applying two approaches – qualitative and quantitative. The data were mainly gathered from secondary sources – the State of Environment Report of Mizoram, Aizawl, and the Ministry of Environment, Forests, and Climate Change, Aizawl, Mizoram. Data on wetlands within the forest areas were also gathered from the Forest Survey of India 2019. Field observation was conducted to verify the data on the ground. The author visited several national parks and wildlife sanctuaries and observed the rich forest ecosystem services. Mizoram obtains a rich floral diversity ranging from tropical wet forests to sub-temperate wet and dry forests and montane evergreen forests. About 86% of the total geographical area is covered by forest. Of which, 50% forest area is covered by bamboo forests. Here, bamboo has 27 species. The valuation of forest ecosystem services – tangible and intangible was carried out and benefits from different forest products were calculated. The study reveals that Mizoram has a very high value in ecosystem services. The annual valuation of tangible ecosystem services was noted from fuelwood, followed by timber, small wood, and poles. In terms of annual valuation of intangible ecosystem services, the highest was from pollination, followed by food and livelihood security, and prevention of soil erosion, and landslides. However, the use of ecosystem services is just negligible. Most of the services are unused. Even, tourism, mainly natural and eco-tourism has high potential but it is not developed yet. If the ecosystem services are used sustainably, the rural poor can enhance their livelihood, and the state government can earn sufficient revenue.

Uncovering the diversity of rodents and shrews in the Chebera Churchura National Park, Ethiopia

Abstract The recently established Chebera Churchura National Park represents a mosaic of savanna and montane evergreen forest. A report on small mammals (2013) showed their relatively high diversity, but species identification was based only on external morphology. We conducted a new field survey and genetic analyses to shed light on diversity and biogeographical affinities of small mammals in this under-explored national park. Based on results of mitochondrial DNA barcoding, 14 species of rodents and two species of shrews, including Crocidura turba (new to the Ethiopian fauna), were identified. Moreover, a new taxon of gerbils – presumably representing a new species – of the genus Gerbilliscus was discovered. We show that forest and savanna species often inhabit the same localities, which can be explained by the mosaic nature of biotopes. These results document the uniqueness of Chebera Churchura NP, especially in comparison with other Ethiopian national parks, and argue for its protection and further development.

Heisteria austroecuadorica (Erythropalaceae): A new species from southeastern Ecuador

Heisteria austroecuadorica, a new species of Erythropalaceae from the conserved evergreen montane forest at the San Francisco reserve, in southeastern Ecuador, is here described and illustrated. It is characterized by the flowers with 10 stamens, and relatively large fruits, with the apex conspicuously depressed, and the calyx not covering the base of the fruits. Heisteria austroecuadorica is assessed provisionally as Endangered.

Potential variables forcing litterfall in a lower montane evergreen forest using Granger and superposed epoch analyses

AbstractThe interplay between long‐term environmental variability and litterfall is complex and through this study, we quantified the response of peak leaf, flower, and fruit litterfall production to such variability in a lower montane evergreen forest located in Doi Suthep‐Pui National Park, Thailand. We observed seasonality in litterfall accumulation with peak leaf and flower litterfalls occurring mostly during the cool and hot dry seasons, while fruit litterfall occurs mostly during the wet season. Probable associations with environmental drivers (barometric pressure, temperature, relative humidity, number of sunlight hours, evaporation, wind speed, and vapor pressure deficit) were tested on a 5‐year litter trap dataset using superposed epoch analysis and Granger causality tests. The tests indicated that significant deviations in barometric pressure, maximum temperature, maximum relative humidity, and wind speed were the most plausible precursors to peak litter production of all components. Additionally, we observed a lag in peak litterfall production relative to climate variability by up to 4 months for most of the climate variables. Changing environmental conditions can affect both the timing and amount of litterfall production, which in turn can alter the nutrient recycling rate and other essential ecosystem services of such forests.

Two new syntopic species of glassfrogs (Amphibia, Centrolenidae, Centrolene) from the southwestern Andes of Ecuador.

We describe two new species of glassfrogs of the genus Centrolene living in syntopy at La Enramada, province of Azuay, southwestern Ecuador. They were found in a small creek in montane evergreen forests at 2,900 m elevation. The first new species is distinguished from all other members of the genus Centrolene by having the following combination of characters: dentigerous process of vomer absent; sloping snout in lateral view; thick, white labial stripe and a faint white line between the lip and anterior ¼ of body; humeral spine in adult males; parietal peritoneum covered by iridophores, visceral peritonea translucent (except pericardium); ulnar and tarsal ornamentation; dorsal skin shagreen with dispersed warts; uniform green dorsum with light yellowish green warts; and green bones. The new species is remarkable by being sister to a species from the opposite Andean versant, C. condor. The second new species is distinguished from all other Centrolene by having the following combination of characters: dentigerous process of vomer absent; round snout in lateral view; thin, yellowish labial stripe with a row of white tubercles between the lip and arm insertion, and a yellowish line between arm insertion and groin; uniform green dorsum; humeral spine in adult males; parietal peritoneum covered by iridophores, visceral peritonea translucent (except pericardium); dorsal skin shagreen with dispersed spicules; ulnar and tarsal ornamentation; and green bones. The second new species is sister to C. sabini and an undescribed species of Centrolene from southeastern Ecuador. Based on nuclear and mitochondrial DNA sequences, we present a new phylogeny for Centrolene and comment on the phylogenetic relationships inside the genus.

Woody species diversity, composition, structure and carbon storage of a dry evergreen montane forest of Essimingor Nature Forest Reserve in Tanzania

Abstract. Mwakalukwa EE, Mwakisu A, Maliondo SMS. 2023. Woody species diversity, composition, structure and carbon storage of a dry evergreen montane forest of Essimingor Nature Forest Reserve in Tanzania. Intl J Trop Drylands 7: 26-36. The biodiversity status of flora and fauna of many forests found on small protruding and isolated hills in most parts of dry areas in Tanzania is largely less studied. Their contribution to climate mitigation options also remains largely unknown. This study assessed the woody species diversity, composition, structure and carbon stocks potential of a dry evergreen montane forest of Essimingor Nature Forest Reserve in Tanzania. The vegetation data were collected from 23 concentric sample plots of 5m, 15m, and 20m radius laid systematically across the entire forest area of 6,100 ha. A total of 54 trees and shrubs species belonging to 29 families were identified. Diversity indices indicated the forest to have a high diversity of woody species. The most important species were Cassipourea malosana, Diospyros abyssinica and Drypetes natalensis. Stand structure comprised 288±173 stems ha-1, basal area of 11.47±7.23 m2ha-1 and standing volume of 27.3±16.3 m3ha-1. The mean above-ground and below-ground carbon stocks were 56.93±34.60 Mg C ha-1 and 34.71±19.72 Mg C ha-1, respectively. The observed high species diversity and carbon density signify the importance of conservation efforts bestowed in this reserve. Quantification of other carbon pools for estimation of the total carbon stock potential of this forest is recommended.

Volume and aboveground biomass models for a dry evergreen montane forest in Tanzania

Abstract. Mwaluseke ML, Mwakalukwa EE, Maliondo SMS. 2023. Volume and aboveground biomass models for a dry evergreen montane forest in Tanzania. Asian J For 7: 45-53. Models available for accurately estimating trees and shrubs' volume and aboveground biomass from dry evergreen montane forests in Tanzania are largely lacking. Therefore, this study was conducted to develop volume, and aboveground biomass models for a dry evergreen montane forest of Lendikinya Forest Reserve found in Northern Tanzania. A total of thirty sample trees and shrubs with a diameter range of 5-58.5 cm were destructively harvested and used in this study. Specifically, the study developed (i) the height-diameter model and (ii) the total volume and aboveground biomass models. The following height, volume, and biomass models appear to be suitable for estimating tree height, volume, and biomass of tree and shrub species found in the study site: Height (m) =2.3249 + 6.6101/DBH + 0.2847DBH (R2 = 0.78, RMSE = 1.79, AIC = 164.37), ln(Volume, m3) = -9.845 + 1.915 ln(DBH) + 1.089ln(Ht) (R2 = 0.97, RMSE = 0.296, AIC = -144.18) and ln(Biomass, kg) = -1.666 + 0.853ln(WD x DBH2 x Ht) (R2 = 0.95, RMSE = 0.324, AIC = 224.13). Both models yielded low bias, hence indicating an excellent fit. These models will be useful in understanding the condition of the forest and the potential of this forest in storing carbon hence, the possibility of benefiting from the ongoing negotiations of REDD+ schemes for payment for avoided deforestation and degradation through sustainable management of the reserve.

Vegetation composition, diversity, stand structure and carbon stock of a dry evergreen montane forest of Lendikinya forest reserve in Tanzania

Abstract. Mwaluseke ML, Mwakalukwa EE, Maliondo SMS. 2023. Vegetation composition, diversity, stand structure and carbon stock of a dry evergreen montane forest of Lendikinya forest reserve in Tanzania. Biodiversitas 24: 551-562. There is limited information on woody plant diversity and vegetation patterns in African dry forests, particularly in East Africa, and hence increasing the interests in understanding species composition, diversity, and structural attributes of catchment forest reserves found in Tanzania. Moreover, tree species composition, species richness, and carbon stock are not well documented in most montane forests in the region, apart from Ethiopia. Their potential in terms of carbon storage is also important for understanding their productivity and the extent to which they can be used in mitigating the effects of climate change. This study assessed vegetation composition and diversity, stand structure and potential carbon stocks of Lendikinya Forest Reserve, a dry evergreen montane forest located in Monduli District in Tanzania. A total of 56 concentric circular plots with subplots of 2 m, 5 m, 10 m, 15 m and 20 m radii were used to collect woody species data on standing trees and stumps across the entire forest of 3,689 ha. A total of 79 species belonging to 36 families were identified. Drypetes natalensis (9.2%), Diospyros abyssinica (7.1%) and Dombeya rotundifolia (6.5%) were the most important species as per the Importance Value Index (IVI). The diversity indices have indicated the forest reserve to have a high diversity of woody species. Stand structure comprises 1,398 ± 679 stems ha-1, basal area of 11.42 ± 5.41 m2ha-1and standing volume of 54.47 ± 24.1 m3ha-1 while the mean carbon stocks were 16.04 ± 7.7 t C ha-1. The alarming disturbances stress the urgent need for increased conservation efforts in order to protect the existing biodiversity and increase carbon storage and enhance water conservation in the reserve.

A time relic: a new species of dwarf boa, Tropidophis Bibron, 1840 (Serpentes: Amerophidia), from the Upper Amazon Basin

The amerophidian snake radiation is a Late Cretaceous superfamily that encompasses two families: Aniliidae, pipe snakes, and Tropidophiidae, dwarf boas. We describe a new dwarf boa snake species, from the Tropidophiidae family, from the cloud forest in northeastern Ecuador. Tropidophis cacuangoae sp. nov. can be diagnosed from its congeners based on external and osteological morphology. The new species inhabits eastern tropical piedmont and lower evergreen montane forests, in the Amazon Tropical Rainforest biome, and is likely to be an Ecuadorian endemic. We also discuss the relationships of the new species with South American tropidophiids and provide a key to the identification of mainland South American dwarf boas.

Community structure and environmental determinants of the bacterial and fungal gut microflora in Hainan gibbons (Nomascus hainanus)

High-throughput sequencing technology was used to establish the OTU (Operational Taxonomic Units) composition and diversity of bacteria and fungi in the gut of three family groups of Hainan gibbons ( Nomascus hainanus ) in the Bawangling National Nature Reserve on Hainan Island, southern China. Firmicutes (47.23%) and Bacteroidetes (36.54%) predominated at the phylum level, while the predominant genera were Prevotella-7 (15.30%), Lachnospiraceae_NK3A20_group (12.49%), and uncultured_bacterium_f_Erysipelotrichaceae (11.79%). At the phylum level, the dominant fungi were Ascomycota (66.41%), as well as Hanseniaspora (23.33%), Schwanniomyces (13.44%), and Pichia (5.43%) at the genus level. We found significant differences in the bacterial OTU diversity (Shannon index) between family groups living in Tropical Lowland or Tropical Montane Rain Forest, compared to those inhabiting Tropical Montane Evergreen Forest at higher altitudes. Bacterial OTU community composition also differed between family groups, unraveling significant differences among the 30 most dominant bacterial core taxa. Furthermore, we unraveled a significant difference of OTU richness in the fungal microbiome (Chao 1) between family groups living at lower altitudes, i.e., Tropical Lowland or Tropical Montane Rain Forest and those inhabiting the Tropical Montane Evergreen Forest. Our analysis further indicated significant differences in the fungal OTU community composition between the three family groups, especially regarding the three most dominant fungal core taxa. Subsequently, two habitat factors, and nine environmental and anthropogenic variables were used to explore possible causes of disparity in the microbial flora of gibbon groups. A factor reduction procedure resulted into three principal components which were correlated to bacterial and fungal OTU richness and diversity using Spearman's rank-order correlations. Bacterial and fungal OTU diversity was high in areas of high altitude, steep slopes, high tree density, but low tree height, while high fungal OTU richness corresponded to high altitude habitats, i.e., in the Tropical Montane Evergreen Forest. Distance to human settlements and to the next water body showed no significant relation with bacterial and fungal richness and diversity.

Effects of Environmental Factors on Carbon Stocks of Dry Evergreen Afromontane Forests of the Choke Mountain Ecosystem, Northwestern Ethiopia

The purpose of this research was to quantify and compare carbon stocks in two selected dry evergreen montane forests of the Choke Mountain ecosystem that are under different management regimes. The study also attempted to assess the carbon stock along environmental gradients. The average carbon stock throughout the whole plots investigated in Anshirava forest (protected) was 180.18 t·ha−1 (53%) in AGB, 111.43 t·ha−1 (33%) in soil, 36.43 t·ha−1 (11%) in BGB, 6.09 t·ha−1 (2%) in USB, 2.69 t·ha−1 (1%) in litter, and 1.36 t·ha−1 (less than 1%) in DW. In Ziba forest (high human intervention), the average carbon stock was 106.71 t·ha−1 (44%) in AGB, 100.07 t·ha−1 (42%) in soil, 21.34 t·ha−1 (9%) in BGB, 5.41 t·ha−1 (2%) in USB, 4.82 t·ha−1 (2%) in litter, and 2.00 t·ha−1 (1%) in DW. The AGB had the greatest carbon share in both forests, followed by soil. In Anshirava and Ziba forests, the mean total carbon stocks (TCS) were 338.18 t·ha−1 and 240.36 t·ha−1, with CO2 equivalents of 1241.14 t·ha−1 and 882.12 t·ha−1, respectively. The study indicated a significant variation between the two forests. Anshirava forest has larger total carbon stocks than Ziba forest. For lower, medium, and higher altitudes, the total carbon stock variation along an altitudinal gradient was 289.67 t·ha−1, 347.93 t·ha−1, and 414.89 t·ha−1 in Anshirava forest and 270.99 t·ha−1, 204.24 t·ha−1, and 224.82 t·ha−1 in Ziba forest, respectively. As a result, a greater amount of carbon was stored at higher altitudes in Anshirava and at lower altitudes in Ziba, with no significant difference in both forests. The total carbon stock variation along slope gradient was 392.60 t·ha−1, 344.59 t·ha−1, and 295.49 t·ha−1 in Anshirava forest and 258.74 t·ha−1, 222.46 t·ha−1, and 171.46 t·ha−1 in Ziba forest for flat, intermediate, and steep slopes, respectively. This resulted in higher carbon being stored in flat slopes in both forests. Also, only at the Ziba site, a significant difference was found along the slope gradient. In each forest, eight distinct aspect facings were observed, with the western (W) aspect containing the highest value of total carbon stock in both forests. Lower values, on the other hand, were recorded in the south (S) and flat (F) aspects of Anshirava and Ziba forests, respectively. The slope aspects of both forests varied significantly. As a result, the research reveals that environmental factors have a significant impact on carbon stock value of Choke Mountain forest ecosystem, but the impact is not consistent among carbon pools.

A recent sighting of the Stripe-backed Weasel Mustela strigidorsa (Mammalia: Carnivora: Mustelidae) in Hkakabo Razi Landscape, Myanmar

In March 2019, a Stripe-backed Weasel, Mustela strigidorsa, was observed in Hkakabo Razi Landscape, Myanmar. Although geographically widespread in southeastern Asia and neighboring areas of northeastern India and southern China, relatively little is known of this small carnivore, which is seldom recorded in camera traps or seen in the wild. In Myanmar, there are 24 previously published records, almost all from mountainous areas. The recent sighting was of a solitary animal, which was foraging at an altitude of 580 m in a thickly vegetated area in montane evergreen forest, close to a stream. The photographs and video footage are the first for the species from the country.

Three new endemic species of Lepanthes (Orchidaceae, Pleurothallidinae) from the highlands of Ecuador.

Three new species of Lepanthes from Ecuador are described and illustrated. These additions to the Ecuadorean flora were recorded in evergreen montane forest and páramo as part of three different research projects conducted during the last five years (2016–2021). Lepanthesoro-lojaensis was discovered in the southwest of El Oro province and is similar to L.jimburae, differing mainly in the much smaller plants, inflorescences and floral parts. Lepanthesmicroprosartima from the western slopes of Pichincha volcano in northern Ecuador resembles L.obandoi but differs in the coloration of the leaves, the inflorescence that are shorter than the leaves and the smaller floral appendix. Lepanthescaranqui, found in eastern Pichincha and Imbabura, is most similar to L.pachychila but differs from it in its much larger plants and different shape of the petals and the floral appendix. Preliminary assessments of the conservation status of the three taxonomic novelties are provided, using the IUCN Red List Categories and Criteria.

Community characteristics of forest understory birds along an elevational gradient in the Horn of Africa: A multi-year baseline

AbstractTropical mountains are global hotspots for birdlife. However, there is a dearth of baseline avifaunal data along elevational gradients, particularly in Africa, limiting our ability to observe and assess changes over time in tropical montane avian communities. In this study, we undertook a multi-year assessment of understory birds along a 1,750 m elevational gradient (1,430–3,186 m) in an Afrotropical moist evergreen montane forest within Ethiopia’s Bale Mountains. Analyzing 6 years of systematic bird-banding data from 5 sites, we describe the patterns of species richness, abundance, community composition, and demographic rates over space and time. We found bimodal patterns in observed and estimated species richness across the elevational gradient (peaking at 1,430 and 2,388 m), although no sites reached asymptotic species richness throughout the study. Species turnover was high across the gradient, though forested sites at mid-elevations resembled each other in species composition. We found significant variation across sites in bird abundance in some of the dietary and habitat guilds. However, we did not find any significant trends in species richness or guild abundances over time. For the majority of analyzed species, capture rates did not change over time and there were no changes in species’ mean elevations. Population growth rates, recruitment rates, and apparent survival rates averaged 1.02, 0.52, and 0.51 respectively, and there were no elevational patterns in demographic rates. This study establishes a multi-year baseline for Afrotropical birds along an elevational gradient in an under-studied international biodiversity hotspot. These data will be critical in assessing the long-term responses of tropical montane birdlife to climate change and habitat degradation.

Floristic composition and structure of the Kibate Forest along environmental gradients in Wonchi, Southwestern Ethiopia

Dry evergreen montane forests in Ethiopia are severely threatened. The status of species composition and structure of forest vegetation are important indicators to understand the trends of threats on local plant communities. In the present study, we examined the floristic composition and structure of the Kibate Forest, Wonchi Highland, Ethiopia along environmental gradients. Sixty-six (30 m × 30 m) plots were established every 100 m interval along altitudinal gradients (2811‒3073 m a.s.l.) in five transect lines for vegetation and environmental data collection. In total, 125 vascular plant species belonging to 104 genera and 52 families were identified. Eighteen species (14%) were endemic to Ethiopia and Eritrea. The two most dominant families, Asteraceae (29 species) and Lamiaceae (eight species) accounted for 30% of the total number of species. The highest number of species (54%) was herbs. Four major community types (viz., Olinia rochetiana-Myrsine melanophloeos, Ilex mitis-Galiniera saxifraga, Erica arborea-Protea gaguedi, and Hagenia abyssinica-Juniperus procera) were identified. The highest species richness, evenness, diversity, and importance value index were in community types 2 and 4. About 82% of the species and all endemic taxa except five were recorded in these two community types. The most dominant woody species were O. rochetiana, E. arborea, Olea europaea subsp. cuspidata, Myrica salicifolia, I. mitis var. mitis, and H. abyssinica with different patterns of population structure. The results show that there was a weak correlation between species richness and altitude. Our findings confirm that environmental variables both with interactions (such as altitude) and without interactions (such as livestock grazing) significantly (p < 0.05) affect species richness. Anthropogenic activities and overgrazing by livestock appear to be the main threat in community types 2 and 3. Urgent management practices and conservation measures such as prohibiting forest clearing and overgrazing and planting indigenous trees through community participation should be considered in community types that are rich in endemic species but are highly threatened.

Impact of disturbance on community structure, biomass and carbon stock in montane evergreen forests of Meghalaya, northeast India

Forest ecosystems play an important role in regulating global carbon cycle. There are very few studies on biomass and carbon (C) stock from the community managed montane evergreen forests of India. In the present study three traditional forests: Sacred forests (SF), Restricted forests (RF) and Village forests (VF) were studied to analyze the level of disturbance, species diversity, stand characteristics, biomass and C stock. In each forest a belt transect of 20 m wide and 250 m long (0.5 ha) was laid for enumeration of all woody individuals having a diameter at breast height (dbh) of ≥ 5 cm. Species richness, density, basal area and population structure varied between the traditional forest types. The aboveground biomass (AGB) was 273 ± 55.5 in the SF, 195 ± 32.12 in the RF and 75.3 ± 17.1 Mg ha−1 in the VF whereas, the corresponding belowground biomass (BGB) was 59.53 ± 8.4, 44.48 ± 7.5 and 19.9 ± 4.3 Mg ha−1, respectively. Overall, there was a 30% reduction of AGB in RFs and 70% in VFs as compared to the SFs. The mean AGBC stock was 129 ± 26.3, 92.49 ± 15.2 and 39 ± 5.7 Mg C ha−1 in SF, RF and VF. The BGBC ranged from a minimum of 6 to 34 Mg C ha−1 in the study sites. The AGB accumulation was greater in intermediate diameter classes (26 − 45.9 cm) in the RFs and VFs whereas in SFs the diameter class >65cm accounted to about 27-69% of the total AGB. Human disturbance had a strong influence on the species richness and stand characteristics that in turn influence the biomass and C stock in the community forests. It is emphasized that the village forests need to be provided with adequate protection for increasing the C storing potential.