Two New Russula Species (Fungi) from Dry Dipterocarp Forest in Thailand Suggest Niche Specialization to This Habitat Type

Dry dipterocarp forests are among the most common habitat types in Thailand. Russulaceae are known as common ectomycorrhizal symbionts of Dipterocarpaceae trees in this type of habitat. The present study aims to identify collections of Russula subsection Amoeninae Buyck from dry dipterocarp forests in Thailand. A multi-locus phylogenetic analysis placed Thai Amoeninae collections in two novel lineages, and they are described here as Russula bellissima sp. nov. and R. luteonana sp. nov. The closest identified relatives of both species were sequestrate species suggesting that they may belong to drought-adapted lineages. The analysis of publicly available ITS sequences in R. subsect. Amoeninae did not confirm evidence of any of the new species occurring in other Asian regions, indicating that dry dipterocarp forests might harbor a novel community of ectomycorrhizal fungi. Macromorphological characters are variable and are not totally reliable for distinguishing the new species from other previously described Asian Amoeninae species. Both new species are defined by a combination of differentiated micromorphological characteristics in spore ornamentation, hymenial cystidia and hyphal terminations in the pileipellis. The new Amoeninae species may correspond to some Russula species collected for consumption in Thailand, and the detailed description of the new species can be used for better identification of edible species and food safety in the region.

Classification and Observed Seasonal Phenology of Broadleaf Deciduous Forests in a Tropical Region by Using Multitemporal Sentinel-1A and Landsat 8 Data

Broadleaf deciduous forests (BDFs) or dry dipterocarp forests play an important role in biodiversity conservation in tropical regions. Observations and classification of forest phenology provide valuable inputs for ecosystem models regarding its responses to climate change to assist forest management. Remotely sensed observations are often used to derive the parameters corresponding to seasonal vegetation dynamics. Data acquired from the Sentinel-1A satellite holds a great potential to improve forest type classification at a medium-large scale. This article presents an integrated object-based classification method by using Sentinel-1A and Landsat 8 OLI data acquired during different phenological periods (rainy and dry seasons). The deciduous forest and nondeciduous forest areas are classified by using NDVI (normalized difference vegetation index) from Landsat 8 cloud-free composite images taken during dry (from February to April) and rainy (from June to October) seasons. Shorea siamensis Miq. (S. siamensis), Shorea obtusa Wall. ex Blume (S. obtusa), and Dipterocarpus tuberculatus Roxb. (D. tuberculatus) in the deciduous forest area are classified based on the correlation between phenology of BDFs in Yok Don National Park and backscatter values of time-series Sentinel-1A imagery in deciduous forest areas. One hundred and five plots were selected during the field survey in the study area, consisting of dominant deciduous species, tree height, and canopy diameter. Thirty-nine plots were used for training to decide the broadleaf deciduous forest areas of the classified BDFs by the proposed method, and the other sixty-six plots were used for validation. Our proposed approach used the changes of backscatter in multitemporal SAR images to implement BDF classification mapping with acceptable accuracy. The overall accuracy of classification is about 79%, with a kappa coefficient of 0.7. Accurate classification and mapping of the BDFs using the proposed method can help authorities implement forest management in the future.

Towards better estimates of carbon stocks in Borneo's logged-over Dipterocarp forests

Tropical forests are a major reservoir of biodiversity and carbon (C), playing a pivotal role in global ecosystem function and climate regulation. However, most tropical forests, especially Borneo's forests in Southeast Asia, are under intense pressure and threatened by human activities such as logging, mining, agriculture and conversion to industrial plantations. Selective logging is known to reduce both above- and below-ground biomass by removing selected large trees, while increasing deadwood stocks through collateral logging damage and creating large gaps in the canopy. The extent of incidental damage, canopy opening and the rate of C recovery were shown to be primarily related to logging intensity. This thesis assesses the long-term effects of logging intensity on five main C pools in Dipterocarp forests in northern Borneo (Malinau District, North Kalimantan) along a logging intensity gradient ranging from 0 to 57% of initial biomass removed in 1999/2000. Our results showed that total C stocks 16 years after logging ranged from 218-554 Mg C/ha with an average of 314 Mg C/ha. A difference of 95 Mg C/ha was found between low logging intensity (< 2.1% of initial biomass lost) and high logging intensity (> 19%). Most C (approx. 77%) was found in living trees, followed by soil (15%), deadwood (6%) and a small fraction in litter (1%). The imprint of logging intensity was still detectable 16 years after logging. Logging intensity was thus shown to be the main driver explaining the reduction of AGC>20, BGC>20, in deadwood and total C stocks and an increase in deadwood. Our results quantify the long-term effects of logging on forest C stocks, especially in AGC and deadwood. High logging intensity (50% reduction of initial biomass) reduced total C stocks by 27%. AGC recovery was lower in high logging intensity plots, suggesting lowered forest resilience to logging. Our study showed that keeping logging intensity below 20% of the initial biomass can limit the long-term effects of logging on AGC and deadwood stocks.

Synthesising Existing Forest Inventory Datasets for Estimating Historical Aboveground Biomass Stocks, Growth and Mortality in Logged-over Tropical Dipterocarp Forests of Kalimantan, Indonesia

Background: Extensive forest inventory data is available from commercial timber companies. For this study, over 20,000 plots were compiled for North, East and West Kalimantan provinces, with more than 17,000 of these exceeding our quality assurance tests. This study aimed to: (1) explore the potential use of existing permanent sample plots and forest inventory data established and measured by timber concessions; (2) assess uncertainties of aboveground biomass (AGB) estimates using various allometric models; (3) analyse the dynamics of AGB in logged-over dipterocarp forests; (4) analyse AGB stocks and emission factors in tropical dipterocarp ecosystems. Methods: Two types of forest monitoring datasets measured by timber companies in Indonesia were compiled and assessed in this study: permanent sample plots (PSPs) (24 1-ha plots), and the overall periodic timber inventory (OPTI) (17,301 plots). We compared various allometric equations for estimating AGB of the plots and developed a simple AGB equation using basal area (BA) as predictor. We further evaluated the AGB growth and mortality using the PSP plots. Results: We found that the model using only tree diameter (D) as a predictor variable tended to be unbiased when aggregating the estimates at larger plots. We also found that BA per hectare could explain the variation of AGB at plot level (adjusted r2 = 0.911; root mean square error [RMSE]: 27.8). We overlaid the OPTI plot with the land cover map and estimated the mean AGB of the associated land cover classes. The mean AGB of primary dryland forest, secondary dryland forest and bush classes were 281.1 + 4.0 Mg/ha, 231.5 + 1.7 Mg/ha and 179.0 + 5.0 Mg/ha, respectively. Nine years after logging, the mean AGB is still lower than the mean AGB two years after logging. The growth rate (2.5%) was still lower than the mortality rate (3.1%), and recruitment (0.2%) did not occur until seven years after logging. Conclusions: The results of this study suggest that the existing forest monitoring data should be incorporated into the carbon accounting system at district, province and national level to improve the estimation of forest biomass and emission factors related to forest degradation and deforestation. However, there is a need for data quality assessment prior the analysis and a standardised platform for nation-wide forest inventory database is therefore required.

Butterfly as bioindicator for development of conservation areas in Bukit Reban Kambing, Bukit Belading and Bukit Tukau, Johor, Malaysia

Ismail N, Rahman A A A, Mohamed M, Abu Bakar M F, Tokiman L. 2020. Butterfly as bioindicator for development of conservation areas in Bukit Reban Kambing, Bukit Belading and Bukit Tukau, Johor, Malaysia. Biodiversitas 21: 334-344. Butterflies are often used as indicator surrogates to evaluate the quality of ecosystems. This is made possible due to their sensitive responses toward environmental fluctuations and habitat changes. Butterflies were collected opportunistically using aerial nets at three hill dipterocarp forests; Bukit Reban Kambing (BRK), Bukit Belading (BB) and Bukit Tukau (BT) of Johor, Malaysia from 8th to 11th March 2016. The objectives of this study are to provide a checklist of butterflies of the hills and evaluate habitat suitability in an effort to support the proposal to gazette the hills as part of the Gunung Ledang protected area. A total of 60 individuals belonging to 23 species, 21 genera, and five families were recorded. Comparing the three hills, BRK recorded the greatest individual and species numbers, followed by BT and BB. BRK recorded the highest Shannon diversity index, H’ (2.272) value, whereas BB presented the highest value of species evenness index, E’ (0.945). MaxEnt modeling of the butterflies in BRK, BB, and BT showed a network of high habitat suitability areas connecting Gunung Ledang and our sampling locations. Despite limited sampling effort, this baseline data could possibly strengthen the effort for gazettement and prevent further pressure from mining activity and land conversion.

Estimating the economic value of absorbing and storing carbon in dipterocarp forests in Ia Pa district, Gia Lai province

Dry dipterocarp forest is one of the ecosystems that features variety of rare plants and animals. The forest in Ia Pa district, Gia Lai province is declining owing to illegal logging and encroachment of forest land for cultivation. Forest degradation can reduce CO2 sequestration, contributing to increasing greenhouse gas emission and global warming. The study was carried out in the 4 quadrats (each 2,500 m2 = 50 × 50 m) in dry dipterocarp forest of Ia Pa district. In each quadrat, 5 sub-quadrats (each 25 m2 = 5 × 5 m) were set up, one at a central point and four at four corners of the quadrat, respectively. Based on the relationship between carbon stock and above-ground biomass, we found that CO2 accumulation in dry dipterocarp forest was 105.6 tons/ha corresponding to the economic value of 12,299,760 VND/ha. Thus, it is necessary to improve forest quality towards sustainable management of dry dipterocarp forest ecosystem and increase the economic value of the forest with respect to environmental services.

A report on diversity and distribution of macrofungi in the Garhwal Himalaya, Uttarakhand, India

We report mycodiversity of the different forest types of the Garhwal Himalaya, Uttarakhand, India. The results drawn here are based on the study carried out in the different forest sites of the Garhwal Himalaya during the rainy season from 2013 to 2015. We collected a total of 323 specimens, including 310 specimens belonging to Basidiomycota and 13 to Ascomycota. Furthermore, 212 specimens of Basidiomycota were identified and grouped into 33 families, 75 genera and 198 species, while 13 specimens of Ascomycota were grouped into 7 families, 7 genera and 11 species. 127 species were found in oak dominated temperate broadleaved forest, while 42 were collected from coniferous and 19 from the mixed woodland composed mainly of Quercus, Myrica, Rhododendron and Pinus trees in middle to higher hills, and Shorea robusta and Tectona grandis in the dipterocarp forests of lower hills. In terms of fungal species distribution in these forests, Amanitaceae, Russulaceae and Boletaceae were found most dominant in oak dominated forests, whereas Tricholomataceae and Cantharellaceae were commonly found in Pinus and Cedrus dominated forests and those belonging to family Cortinariaceae – in mixed forests. Species belonging to the families Agaricaceae, Amanitaceae and Tricholomataceae were found dominant in dipterocarp forest in the lower Himalayan region. The majority of species belonging to all families were found near lower to mid range altitude, which may result from the overlapping effect of atmospheric temperature and climate. The members of seven families, i.e., Russulaceae, Amanitaceae, Tricholomataceae, Boletaceae, Cantharellaceae, Cortinariaceae and Gomphaceae, were found as main ectomycorrhizal forming species from the elevation range of 500-2800 m a.s.l., in all four forest types.

Utilization of waterholes by globally threatened species in deciduous dipterocarp forest of the Eastern Plains Landscape of Cambodia

Deciduous dipterocarp forests throughout Asia provide crucial habitat for several globally threatened species. During the dry season water availability in these forests is primarily limited to perennial rivers and waterholes. Such water sources form an essential part of these dry forests and are used by multiple species, including large mammals and birds, but little is known regarding how waterhole characteristics affect wildlife use. We investigated waterhole utilization by six globally threatened dry forest specialists: banteng Bos javanicus, Eld's deer Rucervus eldii, giant ibis Thaumatibis gigantea, green peafowl Pavo muticus, lesser adjutant Leptoptilos javanicus and Asian woolly-necked stork Ciconia episcopus. We camera-trapped 54 waterholes in Srepok Wildlife Sanctuary, eastern Cambodia, during the dry season of December 2015–June 2016. We measured nine waterhole and landscape characteristics, including indicators of human disturbance. Waterhole depth (measured every 2 weeks) and the area of water at the start of the dry season were the main environmental factors influencing waterhole use. Additionally, waterholes further from villages were more frequently used than those nearer. Our study reaffirmed the importance of waterholes in supporting globally threatened species, especially large grazers, which are critical for maintaining these dry forest ecosystems. The results also suggested that artificially enlarging and deepening selected waterholes, particularly those further from human disturbance, could enhance available habitat for a range of species, including grazers. However, this would need to be conducted in coordination with patrolling activities to ensure waterholes are not targets for illegal hunting, which is a problem throughout South-east Asian protected areas.