Low-altitude Forests Research Articles

Pattern of plant biomass and carbon stock along different elevational forests in eastern Nepal

The primary aim of this investigation was to determine the biomass and carbon stock distribution pattern among different forest stands of diverse elevations in the Morang district of East Nepal. It is noteworthy to estimate carbon stock and biomass of relatively least underexplored forests in east Nepal. The data for estimating the biomass and carbon stocks of the five different forest sites, viz. Bhaunne, Raja-Rani, Murchungi, Adheri, and Sagma located between 100-1300m above the mean sea level, were acquired through the measurement of inventory plots selected randomly. Altogether, 50 sample plots were established within five forest stands located on different elevational zone; within each forest site, 10 sample plots of 20m × 20m size, were laid out for the measurement of trees. In the case of shrubs and herbs, nested plots of 5m × 5m and 1m ×1m, respectively were established. Calculation of the biomass of trees and shrubs was facilitated through the application of an allometric equation, while the biomass of herbs was determined by the harvest method. The carbon concentration in the plant materials was estimated using ash content method. The comprehensive analysis of the stand biomass in the Bhaunne, Raja-Rani, Murchungi, Adheri, and Sagma forest sites were: 815.86 Mg ha-1, 414.19 Mg ha-1, 606.81 Mg ha-1, 519.20 Mg ha-1, and 299.96 Mg ha-1, respectively, with minimum at the Sagma site (high-altitude forest) and maximum at the Bhaunne site (low-altitude forest). As per the variation in stand biomass, the carbon stocks in the forest sites also showed the same trend, but the values ranged from 140.19 Mg C ha-1 to 333.63 Mg C ha-1, with the minimum in the Sagma site and the maximum in the Bhaunne site. The application of the Friedman Test revealed statistically significant variation in the tree biomass between the Murchungi and Sagma sites and also in the shrub biomass between the Adheri and Sagma sites. Similarly, noteworthy variations were observed in the herb biomass of the Bhaunne, Raja-Rani, Murchungi, and Adheri sites as compared to that of the Sagma site. The present study contributes to the understanding of forest ecosystems in context to carbon management.

VELVET: an enclosure vegetation system to measure BVOC emission fingerprints in temperate and tropical climates

The VELVET chamber, utilizing the vegetation enclosure technique, was used to measure biogenic volatile organic compound (BVOC) emissions from representative plant leaves in temperate and tropical climates. This study demonstrates the instrument’s capability, among the various measurements conducted in other studies using the vegetation enclosure technique, in qualifying and quantifying volatile organic compound (VOC) emissions from different tree species. The measurements were performed using Tenax tubes for sampling and GC/MS analysis. The use of PTR-ToF-MS for temperate species allows us to perform flux measurements in the chamber of Norway spruce (Picea abies), European beech (Fagus sylvatica), and common hazel tree (Corylus avellana) in the Puy de Dôme region (France). We found that all species are monoterpene emitters (on average 1.52 ± 0.29 ng m−2 s−1) and more particularly sesquiterpene emitters for C. avellana (7.49 ± 0.70 ng m−2 s−1). In the tropical region of Réunion Island (France), comprehensive measurements were conducted across three distinct vegetation types, on 10 of the most representative species, native and exotic to the island. The study revealed that emissions from these species were influenced by spatial variability, their environment, and the type of the forest (cloud forest, and high- and low-altitude forests). Notably, the research marked a groundbreaking achievement by capturing emissions from endemic species on the island for the first time. The collected data will be added to the biogenic emission inventory of the island, thereby enhancing model simulations by incorporating these new measurements.

Factors affecting the tree and soil carbon stock in Shorea robusta Gaertn. forests along the elevational gradient in Eastern Nepal

Shorea robusta Gaertn. forest is a tropical or sub-tropical forest that has a good potential to store carbon. However, its capacity to store carbon can vary along the elevational gradient. The present study aimed to find the relationship between carbon stock and factors (edaphic, topographic, and physical) affecting it in S. robusta forests along an elevational gradient in eastern Nepal. The study was conducted in three community forests in Sunsari and Dhankuta Districts, which were regarded as lower, middle, and upper altitude forests, respectively. Altogether, 90 circular plots (30 in each forest) were laid for trees. Physico-chemical parameters (nitrogen, potassium, phosphorus, organic matter, moisture, pH, and bulk density) were analyzed from all 90 plots. The carbon stock in trees and soil ranged from 134 t ha−1 to 372 t ha−1 and 27.69 t ha−1 to 60.03 t ha−1, respectively. The tree carbon stock was higher in lower altitude forests. However, the highest soil carbon stock was recorded in the higher altitude forest. Potassium content and pH were positively correlated with the tree carbon stocks. However, organic matter, nitrogen content, and altitude negatively influenced the tree carbon stock. Nitrogen content and altitude positively affected the soil carbon stock. However, potassium content and pH had a negative relationship with soil carbon stock. It is clear that these forests have served as carbon storage facilities, and the potential to store carbon was influenced by edaphic, physical and topographic factors. This research advances our knowledge of how community-managed Sal forests can help to mitigate the consequences of climate change along an elevational gradient.

A low altitude forest dwelling Pyrenean chamois population increases the potential habitat of this subspecies

Aim of the study: To demonstrate if a population of Pyrenean chamois Rupicapra p. pyrenaica can live at low altitudes all year long. This could enlarge dramatically its potential habitat. Area of study: A hunting ground in Sobrarbe County, Pyrenees, Spain, in 2022. Material and methods. We interviewed local hunters to find out when the presence of the subspecies in the area dates back. We performed block counts from April to December in the target area for calculating the size of the population. Main results: There was a presence of at least 15 years of the subspecies living at 600 m asl. The population was at least 18 animals, reproduces, and shows a normal demographic structure of kids, yearlings, adult females, and adult males. Research highlights: Low-altitude chamois populations living in forests could be a result of important ecological changes in high mountain pastures producing migrations to newly suitable areas as low-altitude forests. The potential habitat of the subspecies should be broadened.

Disentangling the impact of photosynthesis and stomatal conductance on rising water-use efficiency at different altitudes on the Tibetan plateau

Tree intrinsic water-use efficiency (iWUE) has dramatically increased in recent decades in global forests. The rising iWUE can be a result of either enhanced photosynthesis rate (A), or decreased stomatal conductance (gs) or both. The underlying physiological mechanisms are still not well understood. Here, we investigated tree-ring isotopes δ13C and δ18O from two tree species in three altitudinal transects on the southeast Tibetan plateau. We found that the relationship between iWUE and ∆18Olw was negative at lower-altitude forests, whereas it was positive at the treeline, indicating that enhanced photosynthesis was the main driver of the increasing iWUE at the treeline, whereas reduction in stomatal conductance was the prime regulator at lower-altitude forests. Furthermore, vapor pressure deficit (VPD) and precipitation during the main growing season showed the highest and significant correlations with leaf water 18O (Δ18Olw) at lower-altitude forests, suggesting that gs was strongly controlled by moisture conditions in the growing season particularly in the lower-altitude forests. These findings shed light to a better understanding of the regulatory mechanism of iWUE changes under the background of rising atmospheric CO2 and climate change and serve to improve the reliability of ecophysiological modeling.

The Soil Environment of Abandoned Charcoal Kiln Platforms in a Low-Altitude Central European Forest

This study examines the soil environment of eight charcoal kiln platforms and the neighboring soil in Czech and Bohemian low-altitude forest stands. Both mixed and undisturbed soil samples were used to assess the hydrophysical soil properties, nutrient content, cation exchange capacity, enzyme activity, and soil active carbon content, while soil color, stoniness, root density, and horizon thickness were estimated in the field. Charcoal-rich horizons had high total organic carbon concentrations and total nitrogen content (about 150% and 40% higher than in the organomineral horizons of the control plot, respectively), with total carbon stocks being higher than those in neighboring forest soils. Fine root density was highest in the charcoal-rich horizons, encouraged by high soil porosity, aeration, and favorable chemical properties. Enzyme group activity differed between individual soil horizons and kiln and control plots, with depolymerization enzyme activity highest in charcoal-rich horizons and humification enzyme activity highest in mineral horizons. Phosphatase, chitinase, and phenoloxidase activity were highest in charcoal-rich horizons, while β-glucosidase activity remained similar across horizons. After long-term abandonment, kiln sites shift from inhospitable sites to localized hotspots for plant and microbial growth, having more favorable physical, enzymatic, and chemical soil properties than the surrounding areas. This study confirmed that kiln production platforms act as microhabitat hotspots, also providing information on a wide spectrum of soil properties linked with soil microorganisms and root growth.

Disturbance Impacts of Logging on Ground Herbaceous Plant Species Richness, Diversity, and Composition of Lowland Rainforest of Papua New Guinea

The impact of logging activities on species richness, diversity, and composition of the ground herbaceous layer of the lowland forest of Papua New Guinea was analyzed. Data from the first multipurpose National Forest Inventory were collected in 52 plots from logged and unlogged low altitude forest on plains and fans (P) and forest on uplands (H) in Madang, West New Britain and Central Provinces. The abundance of 10,609 ground herbaceous plants classified in 174 species from 103 genera and 35 families. Based on importance values, Arecaceae was the dominating family in both logged and unlogged P forest type, while Urticaceae and Arecaceae were dominating respectively in logged and unlogged H forest type. At species level, Donax canniformis and Elatostema beccarii are dominating the P type, and Elatostema novoguineensis and Selaginella durvillei the H type. Analysis of species richness, diversity, and composition showed significant differences between the two types with the H type being richer and more diverse than P type. No differences emerged between logged and unlogged of both types, indicating that the current intensity of disturbance does not seem to have a significant impact on the ground herbaceous layer. Since herbaceous species are an important component of the tropical forest diversity, further inventories must be conducted along a wider elevation gradient to make these results more robust and better observe species turn over patterns and beta diversity.

Carbon stocks of homestead forests have a mitigation potential to climate change in Bangladesh

A total of 176 homestead forests at three altitudes in the Chittagong Hill Tracts, Bangladesh were randomly surveyed to estimate carbon (C) stocks and how stand structure affects the biomass C. All woody vegetations were measured, and litter and soil (0–30 cm depth) were sampled. The tree biomass C stock in the top two altitude forests was up to 37–48% higher than in low altitude, owing to significantly higher tree density and species diversity. An increase in species diversity index by one unit increased the biomass stock by 23 Mg C ha−1. The C stock of litterfall in low altitude forests was 22–28% higher than in the top two altitude due to the deposition of litters downslope and deliberate use of mulch for soil improvement and conservation, resulting in up to 5% higher total soil C. The topsoil C was 10–25% higher than the deeper soil, depending on the altitude. The forest stored 89 Mg C ha−1, indicating a potential for C sequestration in trees outside forest. This study would help policymakers to strengthen the recognition of small-scale forests for mitigation in REDD + (reducing emissions from deforestation and forest degradation, the role of conservation, sustainable management of forests, and enhancement of forest carbon stocks) and support owners through C credits from sustainably managed forests.

Breeding of the endemic Azores Woodpigeon Columba palumbus azorica: a two-year study on Pico Island

ABSTRACT Capsule The Azores Woodpigeon Columba palumbus azorica nested in low altitude forests dominated by native Morella faya, and had an extended breeding season, with high failure rates, particularly during incubation. Aims This work aimed to study the breeding phenology, nesting habitat, clutch size and nesting success of the Azores Woodpigeon. Methods Areas for nest searching were defined randomly. A total of 125 nests were monitored during two breeding seasons on Pico Island, Azores. Survival rates were calculated according to Mayfield method. Results Although most nests were found in forests dominated by introduced Pittosporum undulatum, our study highlights a strong selection for those dominated by native Morella faya. The Azores Woodpigeon seemed to avoid native Laurel forest for nesting. There was a preference for nesting in small or medium trees. Nests heights ranged between 3 and 14 m, with a mean (± se) of 7.0 ± 0.2 m. Egg laying occurred from late-February to early-August (in 2016) or to early-September (in 2017). Clutch size did not vary with time; its mean value was 1.72 ± 0.05 eggs (range: 1–2 eggs). The probability of breeding success was estimated at 0.204 ± 0.113 in 2016 and 0.152 ± 0.103 in 2017. In both years, breeding failure mostly occurred during incubation. Survival differed between the two main nesting habitats, being higher in forests dominated by Morella faya. Conclusions The Azores Woodpigeon does not seem to rely on native Laurel forest for nesting, which confirms previous results. Its preference and higher survival in another strongly threatened habitat is cause for concern. The probability of breeding success was higher than previously reported but still low. Illegal hunting of adult birds, because of alleged damages to crops, might partially explain the high proportion of eggs that did not hatch.

Indicator based integrated vulnerability assessment of community forests in Indian west Himalaya

The Himalaya is often referred to as forested landscape, which provides a range of ecosystem services vital for sustaining life of billions of people. The region is recognized amongst the 35 global biodiversity hotspots for its unique and rich biodiversity. Also, the region is highly vulnerable to perturbations due to anthropogenic disturbances and climate change. Especially the forests in the region are subject to stress from such perturbations. The higher dependency of communities on forests and changing climate has impacts on structure and function of forest ecosystems. This has severe implications for forest dependent communities. Therefore, vulnerability assessment of forests is urgently needed to understand the likely consequences of these changes and responses. Such information would help in developing better management and conservation planning. Earlier studies on vulnerability assessment of forests and forest-dependent people have failed to acknowledge the importance of spatial and temporal aspects of vulnerability investigated through field based observations. Realizing this, present study focuses on forest vulnerability assessment through field based observations along an altitudinal gradient (700–3400 m) in the Indian west Himalaya. This study, for the first time, provides vulnerability assessment of community forests at local scale following integrated approach of multiple indicators across diverse domains. The vulnerability indicators have been identified through a systematic analysis and extensive review of the available literature. A total of 14 indicators in six domains (viz. forest, climate, anthropogenic, topographic, soil and management practices) were identified to assess inherent vulnerability of Community Forests (Van Panchayats) in the target region. Furthermore, Forest Vulnerability Index (FVI) was calculated by integrating the selected indicators across domains. The results revealed high vulnerability at low altitude (<1200 m) forests. Disturbance index, expansion of invasive species and people dependency has emerged as the major factors responsible for forest vulnerability in the region. The value of FVI declined significantly (R2 = 0.51, p < 0.001) with increasing altitude range. The study also analysed perceptions of inhabitant community regarding dependency on forest resources, management practices and status of community forest in the studied area. The outcomes of this study would help in developing management interventions and strategies to ensure sustainable management of forest resources in the targeted landscape in particular and Indian Himalaya in general.

Mammals of Tengchong Section of Gaoligongshan National Nature Reserve in Yunnan Province, China

We conducted field surveys on the mammalian diversity in the Tengchong Section of Gaoligongshan National Nature Reserve in Yunnan Province, China, using camera trap and transect method between April 2014 and May 2018. A total of 46 identifiable mammal species were recorded, including one new record for China and nine new species for the Tengchong County. Of the 46 species, nine are globally threatened (three Endangered and six Vulnerable) and six are Near Threatened on the IUCN Red List of Threatened Species. Species richness of most mammal groups in Tengchong remains high compared to similar sites in neighbouring countries; however, encounter rates for species vulnerable to high hunting pressures were quite low and large carnivores, except the Asiatic Black Bear, were either extirpated or at critically low numbers. Future surveys should cover a wider elevation range and a variety of microhabitats to increase the probability of detecting the species not yet recorded. To enhance the conservation value of the reserve for the diverse mammalian community, poaching and livestock grazing should be further controlled; in addition, protection and restoration of low-altitude forests should be encouraged. Monitoring and research on selected flagship species should also be conducted.

Assessing Forest Structure and Composition along the Altitudinal Gradient in the State of Sikkim, Eastern Himalayas, India

Understanding the structure and composition of native forests is a prerequisite in developing an adaptive forest management plan for Himalayan forest ecosystems where climate change is rapid. However, basic information on forest structure and composition are still limited in many places of the Eastern Himalayas. In this study, we aimed to understand the diversity, structure, and composition of forests and their variations along an altitudinal gradient in Himalayan forests. The study was conducted in the Indian federal state of Sikkim, Eastern Himalayas. We carried out a comprehensive and comparative evaluation of species diversity, stand basal area, and stem density along the altitudinal gradient from 900 m a.s.l. to 3200 m a.s.l. We used stratified random sampling to survey eighty-three plots each 0.1 ha in forest communities that occurred along the altitudinal gradient: (a) lower (900–1700 m) altitude forest (N = 24), (b) mid (1700–2500 m) altitude forests (N = 37), and (c) higher (2500–3200 m)altitude forests (N = 22). We measured and identified all living trees with a &gt;3 cm diameter at breast height in each plot. We counted 10,344 individual plants, representing 114 woody species belonging to 42 families and 75 genera. The family Fagaceae and its species Lithocarpus pachyphyllus (Kurz) Rehder. were reported as the most dominant forest trees with the highest Importance Value Index. The Shannon diversity index was recorded as being the highest for the low-altitude forests, whereas measures of structural diversity varied among forests along with altitude: the mid-altitude forests recorded the highest stem density and the high-altitude forests showed the highest mean stem DBH (diameter at 1.3 m height). One significant finding of our study was the disparity of the size class distribution among forests along the altitudinal gradient. Overall, we found a reverse J-shape distribution of tree diameter signifying the uneven-agedness. However, we showed, for the first time, a complete lack of large trees (&gt;93 cm DBH) in the lower altitude forests. Our study highlights conservation concerns for the low-altitude forests that record high species diversity, although lacked large-diameter trees. We anticipate that our study will provide a comprehensive understanding of forest diversity, composition, and structure along the altitudinal gradient to design conservation and sustainable management strategies

Spatial distribution characteristics of soil organic carbon in subtropical forests of mountain Lushan, China.

The study on the spatial distribution of forest soil organic carbon (SOC) is of great significance for accurate assessment of carbon storage in forest ecosystems. In the present study, by taking eight kinds of forest soils of Mountain Lushan in the subtropical area as the research object, we studied the spatial distribution characteristics of SOC in this mountainous area. The results showed that the SOC content and SOC density (SOCD) of main forest types in the Mountain Lushan were lower than the national and the world average. The soil layer of Lushan forest was thinner, and the SOC and active SOC (ASOC) contents of different forest types and SOCDs are the highest in the surface soil. SOCD of the topsoil accounts for 32.64-54.03% of the total SOCD in the whole soil profile. Surface litter is an important source of SOC, and the different vegetation types are the important reason for the different spatial distribution of SOC in this area. Soil SOC contents in the high-altitude forest (bamboo forest, deciduous broadleaf forest, Pinus taiwanensis forest, evergreen-deciduous forest, and coniferous-broadleaved mixed forest) were higher than those in the low-altitude forest (evergreen broadleaf forest, shrub, and Pinus massoniana forest). However, the difference in SOC content exhibited at the altitude gradient is significantly lower than that in SOC in the soil profile. This indicates that both soil depth and elevation are the important factors that affected SOC distribution. However, the influence of soil depth on spatial distribution of SOC may be more complex than that of altitude. Vegetation types and soil properties are the main reasons for the large differences of reduction rate in the contents of SOC and ASOC.

Characteristics of soil organic carbon mineralization in low altitude and high altitude forests in Wuyi Mountains, southeastern China

Examining the variations of soil organic carbon mineralization at different altitudes is crucial for better understanding of soil organic carbon (SOC) dynamics. We selected the low altitude and high altitude broad-leaved forest soils in Wuyi Mountains as the research object, and incubated them under particular annual average temperature (17 and 9 ℃, respectively) in laboratory to investigate the difference of SOC mineralization characteristics. The results showed that the cumulative SOC mineralization had no significant difference between forest soils at low and high altitude in a 126-day incubation period under ambient temperature. Soil organic carbon content of high altitude soil was significantly higher than that from low altitude. The dynamics of SOC mineralization could fitted by the first-order kinetics. Both mineralization potential (CP) and mineralization rate constant (K) values of two soils had no significant difference, but CP/SOC value and mineralization ratio were significantly higher at low altitude, indicating that the carbon sequestration capacity of low altitude soil was relatively lower than that of high altitude under ambient temperature. Soil microbial biomass carbon and microbial quotients were significantly higher than that of low altitude with the increase of incubation time, indicating that the ability of microbial carbon assimilation was greater at high altitude. On the other hand, the activities of β-1,4-glucosidase and cellobiohydrolase in high altitude soil were higher, suggesting that more labile carbon would be decomposed by soil microbes. The carbon sequestration capacity and microbial carbon utilization efficiency in high altitude soil would be reduced and thus result in a decline of soil organic carbon storage under the scenarios of climate warming.

Variation in small organic N compounds and amino acid enantiomers along an altitudinal gradient

The absolute and relative concentration of small organic N compounds varies among soils, yet we have little idea what drives this variation among soils. Previous studies have noted differences in DON/DIN and amino acid profiles among sites differing in altitude and/or productivity, and thus it seemed plausible that similar factors would have broader effects on the molecular composition of the pool of small organic N. To test this idea we used an altitudinal transect that ranged from a low altitude forest of Eucalyptus regnans with a canopy height averaging 65 m through to coniferous shrubbery that was above the alpine treeline and had a canopy less than 50 cm high. From low to high altitude mean annual temperature decreased 7 °C such that turnover was likely twice as slow at the highest site than the lowest. Capillary electrophoresis-mass spectrometry was used to identify and quantify the main small organic N compounds in free, adsorbed and microbial fractions of the soil; while chiral liquid chromatography-mass spectrometry was used to quantify amino acid enantiomers in hydrolysed soil and the free, adsorbed and microbial fractions of soil.CE-MS detected 66 small (<250 Da) organic N compounds of which 63 could be positively identified. Protein amino acids were a large fraction of the pool of small organic N, but there were also large amounts of non-protein amino acids, quaternary ammonium compounds and alkylamines. There were differences among sites in the profile of small organic N, but these differences were not monotonically related to altitude and there was no evidence pools of small organic N were larger or enriched in recalcitrant compounds at cooler high altitude sites. Among sites there was only modest variation in the molecular composition of the protein amino acid pool probably because protein amino acids are primarily derived from a common source (i.e. depolymerisation of soil proteins). In contrast, there was substantially larger variation within pools of non-protein amino acids, alkylamines and quaternary ammonium compounds; which is probably because compounds from these classes are primarily products of de novo synthesis by specific organisms, and thus molecular composition varies among sites depending on composition of the microbial community.D-enantiomers of amino acids were at low concentrations relative to L enantiomers such that in soil extracts the summed concentration of d-amino acids was 0.5–0.6% of L amino acids, while in hydrolysates D-enantiomers were 0.99% of L-enantiomers. There was no evidence that absolute or relative concentrations of D-enantiomers in free solution, microbial biomass or hydrolysates were larger at high altitude sites, despite turnover likely being slower at the cooler high altitude sites. The absence of an effect of altitude on D/L probably indicates that the turnover of soil proteins is comparatively rapid and thus soil proteins are similarly young even among sites in which mean annual temperature differs by 7 °C.

Seasonal use of remnant forest fragments by understorey forest birds in the Uluguru Mountains, Tanzania: a conservation priority

Forest fragmentation can lead to extinctions of some species at local levels and is eroding bird diversity at an increasing rate. While there is information on the distribution of forest bird species in most of the Eastern Arc Mountain forests, some forests, particularly the smaller fragments, have not been adequately surveyed. Using mist netting we surveyed avifauna in some of the poorly known forests (12.5–25 ha) located 320–1 300 m above sea level in the Uluguru Mountains in order to address their conservation importance. Proportions of seasonal altitudinal migrants were significantly higher in these lower-altitude forests during the cold season than the hot season. The results suggest that these forests support bird species of conservation concern, most of which are forest dependent and some of which make seasonal movements between high-altitude montane forests and lowland/ foothill forests. These forests are important cold-season habitat of altitudinal migrants and further fragmentation should be halted as a matter of regional and global priority.

Investigating the effect of selective logging on tree biodiversity and structure of the tropical forests of Papua New Guinea

Abstract: Unsustainable exploitation of tropical forest resources is raising worldwide concern. In Papua New Guinea (PNG) timber harvesting has been identified as a major contributor to deforestation and forest degradation but its impact on biodiversity is still poorly understood. In this study we investigated the effect of selective logging on tree taxonomic composition, structure and diversity of PNG forests. We used data from 101 one-hectare permanent sample plots (PSPs) belonging to two vegetation types: low altitude forests on plains and fans (type P) and low altitude forests on uplands (type H). We used multivariate techniques to test for significant differences in species composition between plots of different vegetation types and disturbance regimes, identifying the tree taxa to which these differences could be ascribed. ANOVA was used to test for differences between logged-over and unlogged forest PSPs with respect to biodiversity (richness, Shannon’s diversity, Pielou’s evenness) and stand structure (stem density, basal area - BA). Temporal trends of forest features were analyzed using linear regression. Significant differences in taxonomic composition were found between logged-over and unlogged plots of the H type (p = 0.04). No differences were found in richness, diversity and evenness between logged-over and unlogged forest plots, while stem density was higher in the latter (421 ± 153 stems ha-1). Greater BA was found in unlogged forests (30.28 ± 4.45 m2 ha-1) of the H type when compared to the logged-over stands (15.52 ± 4.04 m2 ha-1). We detected positive trends in richness (0.55 ± 0.19 taxa ha-1 yr-1) and diversity after logging. Furthermore, H type forest exhibited positive trends in stem density (9 ± 1 stems ha-1 yr-1) and BA (0.42 ± 0.06 m2 ha-1 yr-1) with elapsed time since harvesting. Our analysis highlights some significant effects of logging activities on biodiversity and structure of PNG forests. Additionally, forests exhibited a significant recovery with respect to richness, diversity and stand structure. These preliminary results will be compared with data collected by the forthcoming National Forest Inventory in order to assess and monitor the effects of human activities and ecological factors on PNG forest biodiversity and develop appropriate conservation measures and sustainable management strategies.

Seasonal elevational movements of Eastern Olive Sunbird Cyanomitra olivacea in the Uluguru Mountains, Tanzania

Little is known about the seasonal elevational movements for most tropical avifauna species. Seasonal elevational movements of the Eastern Olive Sunbird Cyanomitra olivacea were studied along an elevational gradient from 600 to 1 500 m above sea level in the Uluguru Mountains, Tanzania, between May 2005 and February 2006. The recapture of ringed individuals along an elevational gradient across seasons provided evidence for the seasonal elevational movement of the Eastern Olive Sunbird in the Uluguru Mountains and the first documented evidence for this species in the Eastern Arc Mountains as a whole. Due to forest fragmentation and lack of corridors connecting high- and low-altitude forests in the Uluguru Mountains, the results have implications for conservation of the forest along the entire elevational gradient as well as for other forest bird species that have been documented to make seasonal elevational movements in the Uluguru Mountains and the entire Eastern Arc Mountains.

The orb-weaving spider genus Chrysometa in Uruguay: distribution and description of a new species (Araneae, Tetragnathidae)

The spider genus Chrysometa Simon, 1895 comprises 138 species of small (3-5 mm) Neotropical orb-weavers spiders (Nogueira et al. 2011; World Spider Catalogue 2015) mainly associated with arboreal vegetation from intermediate to low altitude forests (Levi 1986). Males of Chrysometa differ from other tetragnathids by having the palpal tibial length approximately as long as its widest point; paracymbium articulated and with several apophyses located at both ends; male cephalic region narrower than in the female and having cymbial ectobasal and ectomedian processes. Females are diagnosed by having femora without trichobothria; abdomen covered with silver guanine patches; a flat epigynum and also by their fertilization ducts originating anteriorly and crossing over the spermathecae (Levi 1986; Alvarez-Padilla & Hormiga 2011).

Seasonal variation in understorey bird species diversity and abundance in the Uluguru Nature Reserve, Tanzania

AbstractThe Uluguru Mountains form a component block of the Eastern Arc Mountains of Tanzania and Kenya and are known for a high degree of endemic vertebrate and plant taxa. Among the Eastern Arc Mountains, the Uluguru Mountains rank second in the number of endemic species. Although the forests in these mountains have received considerable ornithological attention, studies on how forest bird communities in the available low elevation forests are affected by seasons remain patchy and sporadic. Such studies are important because in the Uluguru Mountains, forest destruction in the lower slopes has been severe to an extent that there is very little substantial forest survives below 900 m above sea level. Using mist netting, seasonal variation in understorey bird communities in the remaining low elevation forests in the Uluguru Nature Reserve was assessed between 2005 and 2011. Species diversity and relative abundance of the birds were higher during the cold season in comparison with the hot season possibly due to seasonal elevational movements of some species. Elevational migrants made a large proportion of the avifauna in the study area. The results suggest that low altitude forests are important cold season refugia of elevational migrants and these forests need continual protection.