Submontane Forest Research Articles

A new species of Physocrobylus (Caelifera: Acridoidea: Acrididae: Coptacrinae), with notes on the phenology and habitat of the genus

A new species of Physocrobylus, P. venetussp. nov., is described from the Nguru Mountains of Tanzania. It is the third species in the genus restricted to Tanzanian localities. While P. venetussp. nov. and P. tessa Hochkirch prefer moister forest communities from lowland to submontane forest in the East Usambara and Nguru Mountains, P. burtti Dirsh is an inhabitant of Miombo woodlands.

Phylogenetic dynamics of Tropical Atlantic Forests

Environment and plant interactions are important drivers of forest community assembly and dynamics. This study explored how forest dynamics influence the phylogenetic structure of Tropical Atlantic Forests. We hypothesized that: (a) maximum diameter and maximum height are conserved traits within the phylogenetic lineages; (b) the set of dead large trees are more closely related to the set of living large trees than expected by chance; (c) mortality, recruitment and biomass variation are related to phylogenetic effects. We gathered data from 12,920 trees with diameter (DBH) ≥ 3.2 cm, from nine sites, distributed among seasonal semideciduous submontane forests, evergreen dense forests and gallery forests in Brazil. With this data we computed annual dynamic rates (mortality, recruitment, loss and gain of basal area), phylogenetic turnover and phylogenetic distance between dead and surviving trees, and recruits and surviving trees, within distinct size (DBH) classes. We found an overall tendency for higher mortality than recruitment, and higher gain than loss of basal area. Concomitantly, we detected an increase of phylogenetic clustering caused by exclusion of distant relatives, and a phylogenetic overdispersion among large trees (≥ 30 cm DBH) caused by exclusion of close relatives. We also observed high values of phylogenetic distance among recruits and surviving trees across different size classes. As the maximum height and maximum diameter are conserved functional traits, these findings indicate that negative interactions such as competition-like effects among large trees influence the phylogenetic structure and the forest dynamics, meanwhile successional change continuously excludes unfit phylogenetic lineages while recruits fit phylogenetic lineages.

First Community in Abandoned Pasture Lands or Crops in Eastern Cuba’s Rainforest over Metamorfics Rocks

Miconio prasinae–Cyatheion arboreae alliance is described. Although it has five associations, we address three in this work, corresponding to immediate, secondary and early successional communities in abandoned pasture lands or crops in submountains rainforest over metamorphic rocks. The objective of this work is to study the first communities in used and abandoned fields, because they are of a great importance in the understanding of the vegetation’s evolution and for management purposes. In the submontane forest on the metamorphic complex, the destruction of mature vegetation produces important losses in climatic biodiversity and transcendental changes in ecosystem composition. The change in soil use, especially the transformation to pastureland, has favored the development of herbaceous and shrubby plant communities. This study is not only of practical relevance in describing the associations of the pine forests the plant associations and the study of the ecological conditions in which they develop, but its results can be used as a working tool in the environmental management and silviculture for the restoration of degraded areas. The study of diverse Cuban vegetation types suggests that the methodology of Zurich Montpellier’s school is more effective as compared to other authors because its syntaxa is good to recognize and is able to transform in a forest typology. The main species are pioneers heliophilous with a type of r selection.

Climate-human-landscape interaction in the eastern foothills of Mt. Kilimanjaro (equatorial East Africa) during the last two millennia

The Mt. Kilimanjaro region is known for its long history of intensive agriculture, but the temporal extent of human activity and its impact on the regional ecosystem are not well known. In this study, climate-human-landscape interactions during the past ~2200 years were examined using climate and vegetation proxies extracted from the continuous and high-resolution sediment record of Lake Chala. Ancient-to-modern regional human activity is documented against a backdrop of long-term vegetation dynamics in the low-elevation savanna woodland southeast of Mt. Kilimanjaro and riparian forest within Chala crater. During prolonged dry periods (~1170–1300 CE), succulent dry crater forest expanded relative to the moist lakeshore forest. The savanna landscape surrounding Chala crater was relatively stable through time, except that savanna grasses were stimulated by higher precipitation, consistent with the fuel-limited fire regime evidenced in the charcoal record. Expansion of subalpine ericaceous vegetation and a general decline in Afromontane forest taxa on Mt. Kilimanjaro after 550 CE may reflect a lowering of its upper forest line. The earliest robust signature of human influence on regional vegetation involves an increase in ruderal (weedy) plant taxa around 1100 CE, possibly associated with the development of Chagga homegardens and associated agroforestry in the submontane forest zone. A first hint of cereal agriculture (likely sorghum) is observed around 1550 CE, followed by a more robust signature from 1780 CE onwards which likely reflects the start of lowland irrigation agriculture. From 1780 CE we also find the first undisputed appearance of maize, introduced to East Africa about a century earlier.

KAJIAN AUTEKOLOGI Areca vestiaria Giseke PADA HUTAN PEGUNUNGAN BAWAH NGATA TORO KAWASAN TAMAN NASIONAL LORE LINDU SULAWESI TENGAH

The research entitled Autecolgical study of Areca vestaria in Sub-Montane Forest Lore Lindu National Park at Toro village area has been conducted from April to May 2016. The objective of the research was to know the biotics and abiotics factor arround the habitat of Areca vestiaria. The results showed that The highest important value index (IVI) of tree, sapling, pole and seedling species wereFicus ampelos (68.69%), Aphanaximis polistachy (40.01%), Ardisia lateriflora (31.73%) and Ardisia lateriflora (19.23%) respectively. The insects actively interacted with A. vestaria were black ant and bee. Based on soil analyzed indicated that pH of soil 6.6 while N, P and organic matter concentration were 0.26, 0.207 mg/g and 76.1% respectively. A. vestaria grew under light intensity of 540.4 lux, humidity of 76.1% and average daily temperature of 24.4%.

Human–black bear interactions in Northern Mexico

ABSTRACT In Mexico, black bear (Ursus americanus) is an endangered species. Human invasion of its habitat has provoked a change in its foraging behavior. Human–black bear interactions (HBIs) occur in a variety of locations and create conflict. Spatial information can predict the probabilities of interaction and identify environmental variables. We implemented ecological niche models to identified areas with high probability of HBI. Results indicated that the occurrence of interactions was related to submontane scrub, forest, and urban zones. Verification was carried out in the field, which confirmed the high performance and accuracy of the probability model.

Population structure and genetic diversity ofMagnolia cubensissubsp.acunae(Magnoliaceae): effects of habitat fragmentation and implications for conservation

AbstractGenetic data on threatened plant populations can facilitate the development of adequate conservation strategies to reduce extinction risk. Such data are particularly important for species affected by habitat fragmentation such asMagnolia cubensissubsp.acunae, a Critically Endangered magnolia subspecies endemic to Cuba. Using genetic data from 67 individuals, we aimed to evaluate the effect of habitat fragmentation on two subpopulations in the Guamuhaya mountain range, in Topes de Collantes Protected Natural Landscape and Lomas de Banao Ecological Reserve. We characterize the structure and genetic diversity of these subpopulations, with the objective of managing their conservation more effectively. We used Landsat satellite images to determine land-cover types at the two locations and calculated indices of habitat fragmentation. For genetic analyses, we extracted DNA from the leaf tissue of individuals from the two subpopulations and used 11 microsatellite markers to genotype them. We calculated heterozygosity, allelic richness and theF-statistics, to evaluate genetic variability. The montane rainforest in Topes de Collantes was most affected by habitat fragmentation, with smaller patches of more irregular shapes, compared to submontane forest at this location and both montane and submontane forests in Lomas de Banao. Genetic diversity was higher in Topes de Collantes, but we found no genetic differentiation between subpopulations. Our findings suggest the two subpopulations can be considered a single evolutionary unit and conservation entity. We propose to use individuals from both subpopulations for reinforcement to increase the overall genetic diversity of the subspecies.

Diversity of Amphibians in the Eastern and Southern Parts of the Sinharaja Rain Forest

The Sinharaja forest reserve is one of the least disturbed and biologically unique tropical lowland rain forests in Sri Lanka with the eastern Sinharaja consisting of moist sub-montane forests providing habitat par excellence for amphibians. However, the diversity of amphibians in the eastern and southern sections of Sinharaja is inadequately researched. Hence, this research focuses on studying amphibian diversity in lowland rain forests and sub-montane forests in eastern and southern Sinharaja. This research is guided by Quantitative Deductive research methodology and 16 line transects and 16 quadrate samples are used for primary data collecting. Twenty-four amphibian species were identified, 22 (92%) species of which are endemic to Sri Lanka. The amphibian species identified included 5 vulnerable species, 7 endangered species and 8 critically endangered species. The highest number of species, including endangered and critically endangered species were recorded in the sub-montane forests than in lowland rain forest. Major threats to the existence of amphibian species were issues related to biopiracy including loss of forest genetic resources and wildlife smuggling, illegal forest utilization practices, gem mining, illegal forest encroachments and unethical tourism practices. Thus, the Forest Department and other responsible authorities must attend to minimize the effects of these negative human impacts on these vulnerable areas in order to protect and conserve the diversity of sensitive amphibian species in their habitats.

Diversity of plant species and the presence of Invasive Alien Species (IAS) in the Sub-Montane Forest at Pakenjeng Region, Southern Part of Garut, West Java

Plant species diversity is an important ecological characteristic, especially to observe the complexity of forest ecosystems. The research is carried out to elaborate on the species composition, species diversity and the forest structure, and to identify the presence of invasive alien species (IAS) in the sub-montane forests at the Pakenjeng region, the southern part of Garut, West Java. The vegetation survey method used was a stratified sampling technique with the transects and line plots as sampling units for inventorying the trees, forest regenerations, and ground cover. These data are further analyzed to obtain information on abundance, dominance, importance value index (IVI), species diversity and evenness. Based on the species composition, the forest formation was categorized as a primary sub-montane forest with high species diversity characterized by the presence of tree species such as Altingia excelsa, Lithocarpus sundaicus, Castanopsis spp. and Podocarpus spp. showing the curve of inversed-J for horizontal structure with A, B and C canopy layers. The species of Eupatorium inulifolium, Musa zebrina, Piper aduncum and Lantana camara are categorized as IAS.

Quantitative description and comparison of the advertisement calls of two species of probreviceps (Anura: Brevicipitidae) from the Uluguru South Mountains, Tanzania

ABSTRACTThe brevicipitid frog genus Probreviceps is confined to the montane and submontane forests of the Eastern Arc Mountains. In this article, quantitative description and the comparison of advertisement calls of Loveridge’s forest frog Probreviceps loveridgei and the Uluguru forest frog P. uluguruensis from the Uluguru South Mountains in Tanzania are provided. The two species share the same habitat but occur at different altitudes. Description of the advertisement calls and analyses were carried out using CANARY 1.2 software. A thorough descriptive analysis of the advertisement calls of the two species is provided, including numerical information about the spectral and temporal features of the calls and species’ calling behaviour. A characteristic audiospectogram and oscillogram are presented for each species. Spearman rank correlation analysis was used to identify the temperature-dependent acoustic variables, and the temperature effect on these variables was quantified using linear regression models. The two species exhibited variations in both spectral and temporal structure of the call. Interspecific variations were observed in the dominant frequency, call duration, call rate, pulse rate, note rate and number of notes per call. The advertisement calls emitted by P. loveridgei are higher pitched than those emitted by P. uluguruensis. In both species, dominant frequency and call rate increased significantly with ambient temperature, whereas the call duration decreased (non-significantly) with ambient temperature. Audiospectogram correlation and discriminant analysis showed distinctiveness in the quantitative characteristics of each species’ call. Dominant frequency, call duration and call rate were strong discriminating parameters which mostly accounted for interspecific variation in the advertisement calls.

Effects of human disturbance and altitudinal gradient on myriapod species richness and abundance at Mount Kala, central Cameroon

Myriapods are remarkably diverse and encompass many endemic species, yet they remain poorly studied in Cameroon. We investigated the influence of anthropogenic activities on myriapod assemblage structures along an altitudinal gradient at Mount Kala. Myriapods were collected by pitfall trapping, hand sorting and litter sifting in four altitudinal levels and habitats (820 m, 920 m, 1 020 m and 1 120 m above sea level) from November 2017 to July 2018. A total of 1 131 individuals from 58 species in 3 classes (Diplopoda, Chilopoda and Symphyla), 36 genera and 17 families were recorded at Mount Kala. The Diplopoda was the most abundant and diverse class (94.69% and 49 species), followed by Chilopoda (4.51% and 8 species) and Symphyla (0.80% and 1 species). Aporodesmus gabonicus Lucas, 1858 and Karkinikus colonus Attems, 1914 were the most abundant species in the study site. Along the altitudinal gradient, the myriapod species richness decreased in anthropised areas (820 m to 920 m above sea level), reached a maximum in transitional forest (920 m to 1 020 m above sea level) and slightly decreased within the submontane forests (1 020 m to 1 120 m above sea level). Myriapod abundance followed the same trend. However, our results also indicate a high species richness turnover observed between altitudinal levels suggesting that most species are adapted to a particular habitat and could serve as indicators of environmental changes. Accordingly, this study demonstrates a negative relationship between anthropisation and myriapod diversity, as well as the implications towards the management of the Mount Kala forest.

Addressing the Vepris verdoorniana complex (Rutaceae) in West Africa, with two new species

SummaryVepris verdoorniana (Rutaceae) has long been regarded as a widespread and variable species occurring from Guinea to Gabon. Recent evidence has shown that the original material from the type locality in Cameroon consists of two different species, V. verdoorniana in the strict sense, endemic to Lower Guinea (Cameroon, Gabon and C.A.R. in W-C Africa) and V. letouzeyi Onana, which was thought to occur from Guinea to Cameroon. In this paper we show that the West African (Upper Guinea) material previously referred to as V. letouzeyi/V. verdoorniana is separate morphologically from that in Cameroon (Lower Guinea). In fact the West African material referred to comprises two distinct species, here described as V. occidentalis Cheek & Onana (Guinea to Ghana, but probably extending to Benin) a tree of lowland marginal dry evergreen and semi-deciduous forest, and V. fer Cheek, a species restricted to four mainly lower submontane forest locations on iron substrates in Liberia and Sierra Leone (also Upper Guinea). Vepris occidentalis is here assessed as Least Concern due to its wide range and high frequency, whilst V. fer is assessed as Endangered due to the low number of locations and threats from iron ore mining projects. Both new species are illustrated and mapped.

Ecological drivers of pteridophyte diversity and distribution in Togo (West Africa)

• Submontane forests concentrate 90% of the local pteridophyte species in Togo. • Humidity, insolation and disturbance are the main drivers of pteridophyte presence. • Human disturbances are more damaging to terrestrial pteridophyte species. • Pteridophyte species are reliable indicators of conditions of their habitat in Togo. The conservation and sustainable management of biodiversity requires an understanding of the biotic and abiotic factors that condition the presence and survival of organisms in natural habitats. The global distribution and ecological hypersensitivity of pteridophytes have made them ideal candidates for studying the impact of biotic and abiotic factors on levels of biodiversity. This study aims to determine the effect of vegetation cover, human disturbance, and climatic factors on the distribution and diversity of pteridophytes in Togo with a view to guide conservation efforts. Our data comprises 130 plots of 500 m 2 representing all ecological zones of the country, complemented by several opportunistic collections. After determining the patterns of pteridophyte distribution, multivariate analysis of variance and the calculation of diversity indicators made it possible to determine the influence of the factors studied. We found that pteridophyte species diversity and distribution in Togo are strongly influenced by climatic variables, with more than 90% of species diversity being concentrated in the submontane forest areas. Humidity related variables, insolation, and human disturbances are the main drivers of their distribution. Species diversity is positively associated with an increase in humidity, but decreases with increasing insolation and human disturbance. Importantly, our results emphasize the association of specific species to particular conditions created by climate, land cover, and human disturbances, highlighting the role of pteridophyte species as indicators of environmental conditions or exposure to stress. Within humid forest areas, our analysis of the impact of disturbance indicates that about a quarter of the pteridophyte flora of humid forests is sensitive to minor disturbances, whereas almost all rainforest species decline in the face of high levels of disturbance. Agroforests are a particular case of moderately disturbed rainforests, and have the potential to harbour at least 30.5% of Togolese rainforest pteridophyte species diversity. We conclude that the conservation of pteridophytes in Togo requires the protection of submontane rainforests and the adoption of less destructive practices in terrestrial species habitats in coffee/cocoa-based agroforests.

Short Communication: Floristic survey of vascular plant in the submontane forest of Mt. Burangrang Nature Reserve, West Java, Indonesia

Abstract. Cahyanto T, Efendi M, Shofara RM. 2019. Short Communication: Floristic survey of vascular plant in the submontane forest of Mt. Burangrang Nature Reserve, West Java, Indonesia. Biodiversitas 20: 2197-2205. A floristic survey was conducted in submontane forest of Block Pulus ​​Mount Burangrang West Java. The objectives of the study were to inventory vascular plant and do quantitative measurements of floristic composition as well as their structure vegetation in the submontane forest of Nature Reserves Mt. Burangrang, Purwakarta West Java. Samples were recorded using exploration methods, in the hiking traill of Mt. Burangrang, from 946 to 1110 m asl. Vegetation analysis was done using sampling plots methods, with plot size of 500 m2 in four locations. Result was that 208 species of vascular plant consisting of basal family of angiosperm (1 species), magnoliids (21 species), monocots (33 species), eudicots (1 species), superrosids (1 species), rosids (74 species), superasterids (5 species), and asterids (47), added with 25 species of pterydophytes were found in the area. The three families of plants are Lauraceae (10 species), Urticaceae (9 species), and Rubiaceae (8 species) dominating those areas. Fourteen species belong to IUCN red list: Least concern/LC (12 species), Vulnerable/VU (1 species), and endangered/EN (1 species). Furthermore, Castanopsis argentea A.DC, Pinanga javana Blume and Amorphophallus decus-silvae Backer & Aldrew belonging to protected plants are also found in the area. Based on the assessment of analysis vegetation, the forest has experienced disturbance, the density of trees is commonly low and has a lot of gaps. Many vacant lots are found. On the other side, there is the presence of invasive plant species that may slow down a succession into climax growth of local plant.

Uzungwa Scarp Nature Forest Reserve: a unique hotspot for reptiles in Tanzania

While knowledge of African vertebrate biodiversity has increased dramatically in recent years, the field of herpetology which encompasses many threatened and endemic species, has lagged behind, and many areas have not been adequately explored. Intensive field work was conducted during the rainy season from December 2017 to April 2018 to assess reptile occurrence mostly in previously unexplored areas of the Uzungwa Scarp Nature Forest Reserve (USNFR) which is part of the Udzungwa Mountain ranges in the Eastern Arc Mountains (EAM), and adjacent agricultural areas. Bucket pitfall traps, funnel traps, night transects and opportunistic search methods were used to sample reptiles across four zones: in lowland, submontane and montane forests of the USNFR, and in neighboring farmlands. Forty-five reptile species across 14 families were recorded, mostly concentrated on the lowland and submontane forests. The number of endemic and threatened species in the USNFR reaches 20 and 14 respectively, and most are found in the submontane forest. Nineteen species were new records for the USNFR, five of them representing range extensions. Reptile species richness, abundance and diversity differed significantly across the four zones, except between montane and farmland zones and between lowland and submontane. However, farmland zone was discordant from other zones in terms of species composition. This study adds to the importance of the EAM not only in harbouring large numbers of species but also as an important hotspot for endemic and threatened reptiles. It also calls for proper land-use practices in farms adjacent to protected areas for sustainable conservation of biodiversity.

Climate and seasonal rainfall anomalies along an elevational gradient in the El Sira Mountains, Peru, and their impacts on tree radial growth

The explicit purpose of this study was to characterize climate and vegetation along the western slope of the El Sira Mountains (Peru) and evaluate radial tree growth in response to seasonal rainfall anomalies. From May 2011 until September 2015, we monitored radial stem growth of 67 trees using point dendrometers and measured climate within five sites along an altitudinal gradient. The transect extends from lowland terra firme forests, over submontane forests, late and mid successional montane cloud forests up to exposed elfin forests. Monthly rainfall estimates by the TRMM PR satellite (product 3B42) were highly correlated with our rain gauge observations but underestimate rainfall at high altitudes. Different intra-annual tree growth patterns could be identified within each elevational forest type, showing species with strictly seasonal growth, continuous growth or alternating growth patterns independent of the seasons. Stem growth at each site was generally larger during rainy seasons, except for the elfin forest. The rainy season from October 2013 to March 2014 was extraordinarily dry, with only 73% of long-term mean precipitation received, which resulted in reduced radial growth, again with the exception of the elfin forest. This indicates that montane tropical rain forests may suffer from prolonged droughts, while exposed ridges with elfin forests still receive plenty of precipitation and benefit from receiving more solar radiation for photosynthesis.

An overlooked hotspot for birds in the Atlantic Forest

Montane and submontane forest patches in the state of Bahia, Brazil, are among the few large and preserved Atlantic Forests remnants. They are strongholds of an almost complete elevational gradient, which harbor both lowland and highland bird taxa. Despite being considered a biodiversity hotspot, few ornithologists have surveyed these forests, especially along elevational gradients. Here we compile bird records acquired from systematic surveys and random observations carried out since the 1980s in a 7,500 ha private protected area: Serra Bonita private reserve. We recorded 368 species, of which 143 are Atlantic Forest endemic taxa. Some 16 and 13 species are threatened at the global and national levels, respectively. If one accounts for subspecies, the number of Brazilian threatened taxa raises to 21. Species composition differs between lower and higher elevations, in which case lowlands harbor Amazonia-related taxa, whereas highlands are the home of Atlantic Forest-related taxa.

Current records of porcupine in northeast India: distribution, habitat preference and conservation

Porcupines are found in different parts of Northeast India. Three species of porcupines have been reported from northeast India. Except for some discrete reports, the detailed distribution of porcupine has not yet been studied. To have a clear idea of the present distribution of porcupines in northeast India, their habitat preference, all available reports and literature have been reviewed. The study revealed Himalayan porcupine is distributed all over northeast India and have wide environmental tolerance from tropical to the temperate forest and sub-montane forest. Several anthropogenic threats including poaching for its delicious meat have reduced its population at an alarming rate. Priority should be given to the conservation of the species before reaching to endangered level.

Vegetation, floristic composition and structure of a tropical montane forest in Cameroon

Background: The Rumpi Hills Forest Reserve (RHFR) is a montane forest area in south-western Cameroon. Although RHFR is presumed to be rich in biodiversity and vegetation types, little information exists regarding its floristic composition and vegetation patterns.Objectives: Our goal was to characterise vegetation patterns in the reserve and to understand how elevation influences distributions and diversity of species. We aimed to provide a first detailed plant species inventory for this important forest area, as well as basic information on forest structure.Method: We characterised floristic composition and vegetation patterns of the reserve in 25 1-ha plots along an elevational gradient from 50 m to 1778 m. In each plot, trees and lianas of diameter at breast height (dbh) ≥ 10 cm were measured; shrubs 10 cm were measured in nested plots of 0.01 ha.Results: In all, 16 761 trees, shrubs and lianas with dbh ≥ 1 cm were censused, representing 71 families, 279 genera and 617 morphospecies. Floristic composition ranged from 94 to 132 species, with a mean of 117.5 species per hectare in lowland forest (50 m – 200 m) and 36–41 species, with a mean of 38.5 species per hectare in montane cloud forest (1600 m – 1778 m) near the summit of Mount Rata. Two-way indicator species analysis classified the 25 plots into six vegetation types corresponding to lowland evergreen rainforest, lowland evergreen rainforest on basalt rocks, middle-elevation evergreen forest, submontane forest, transitional submontane forest and montane cloud forest. In all, 0.006% of the reserve was included in our sample plots. Detrended correspondence analysis highlighted the importance of elevation in shaping vegetation patterns.Conclusion: The RHFR is composed of different vegetation types, which show impressive variation in terms of structure, species composition and diversity. The detailed, fine-scale inventory data obtained in this study could be useful in planning efficient management of this and other montane tropical forests.

Decomposition of Leaf Litter in Semideciduous Submontane Forest, in The Southern State of Espírito Santo

ABSTRACT The objective of this work was to understand the relationship between decomposition of leaf litter and climatic elements and determine the mineralization of nutrients in the decomposition process in a fragment of Semideciduous Submontane Forest, located in southern state of of Espirito Santo. Overall, 84 litterbags were deposited in 12 permanent plots, collecting one litterbag per plot for 30, 60, 90, 150, 210, 270 and 360 days after the beginning of the experiment. The leaf material remaining in the litterbag was oven-dried and weighed, with later analysis of nutritional compounds. The leaf litter decomposition rate was 1.42, 75.95% of decomposing litter at the end of the evaluation period. Mineralization occurred in the following order: K, Corg., Mg, S, P, N and Ca. There was a positive correlation of average and minimum air temperature, as well as accumulated precipitation and leaf litter decomposition .