Average Total Biomass Research Articles

Evaluating sampling designs and deriving biomass equations for young plantations of poplar and willow clones

Short-rotation intensive culture (SRIC) for bioenergy production is at its pre-commercial stage in Canada. To be economically viable, these types of plantations need an accurate examination of actual yields, which requires precise and efficient estimation methods (i.e., specific allometric equations and sampling methods). At six SRIC plantations from three Canadian provinces (Quebec, Ontario and Alberta), 6 willow and 10 poplar clones were sampled and clone allometric equations were developed to estimate plant biomass. A stem selection approach was successfully used to develop plant allometric equations, reducing the number of stems to be measured by up to 81% in coppiced plantations relative to traditional stem equations. Clone-specific equations were more accurate than equations for groups of clones, but the difference in terms of RMSE% was generally small (less than 5%). Using extensive measurements of all the plants inside a plantation and a simulation approach, we also compared five sampling methods (simple random sampling, stratified sampling, systematic sampling, random and systematic cluster sampling) to estimate total biomass inside the plantation. Simple random sampling and stratified random sampling were the most efficient methods (i.e., increased precision for equal sample size) for the estimation of average plant biomass, survival and total plantation biomass. Stratified random sampling (based on the position inside the plantation) made it possible to reduce the sample size as compared to simple random sampling, but only at higher levels of precision (e.g., 25 less plants at 5% precision). Applications of sampling using remote sensing techniques and GIS are briefly discussed.

Biomass Partitioning and Accumulation in Tectona grandis (Teak) at Young Stage

Forest biomass is considered to have a large potential for temporary and long-term carbon storage as biomass. Enhancement of biomass increase via forest plantation establishment can be considered as an effective method of mitigation of atmospheric carbon dioxide. However, due to the difficulty of measuring the below ground biomass accumulation, most of the tree and forest related biomass studies have been conducted on the above ground components of the trees. Therefore the present study was conducted to identify the biomass accumulation over the age and its partition in above and below ground segments of young teak trees by destructive sampling. Teak trees of 55, 67, 79, 91 and 103 months growing in a single plantation in Puttlam was selected for this reason. Three trees of each age were randomly selected and carefully uprooted with the minimum damage to the roots. Then each tree was separated into main stem, primary, secondary and tertiary branches and roots and the weights were measured. Representative samples of each segment of the tree were oven dried at 72° C for three days. Then the biomass of each segment was calculated. The average total tree biomass increased from 28.430 to 79.760 kg from 55 to 103 months. Comparatively, the highest biomass was recorded in the main stem (63.5%) followed by primary branches (15.7%). The third highest biomass was recorded from the roots (11.7%) and the lowest biomass was recorded in tertiary branches (3.6%). A strong exponential relationship was observed between the tree age and whole tree biomass increase with the R2 of 97.7%. It further revealed that the biomass increase of teak is rising with a rapid rate even at the age of 10 years. Keywords: Tree biomass, Biomass partition, Teak

Modeling biomass and soil carbon sequestration of indigenous agroforestry systems using CO2FIX approach

The fifth assessment report of the intergovernmental panel on climate change (IPCC) estimated that by 2040 agroforestry would offer high potential of carbon (C) sequestration in developing countries. However, the role of tropical agroforestry in C sequestration and in climate change mitigation has only recently been recognized by United Nations Framework Convention on Climate Change (UNFCCC). This is partly due to the lack of reliable estimates on the sequestration potential in biomass and soil carbon pools over time. The aim of this study was to analyze the changes in the biomass and soil carbon pools of three indigenous agroforestry systems in south-eastern Rift Valley escrapment of Ethiopia using CO2FIX (v. 3.2) model. The agroforestry systems studied were Enset (Ensete ventricosum)-tree, Enset-coffee-tree, and Tree-coffee systems. To run the model, empirical data collected from 60 farms (20 farms for each agroforestry system) and literature were used as inputs to parameterize the model. Simulations were run over a period of 50 years. Average simulated total biomass C stocks was the highest for Tree-coffee system (122Mg Cha−1), followed by the Enset-coffee-tree (114Mg Cha−1) and Enset-tree system (76Mg Cha−1). The tree cohort accounted for 89–97% of the total biomass C stocks in all the studied systems, and the reminder was shared by Enset and coffee cohorts. The total average simulated total C stocks (biomass and soil) were 209, 286 and 301Mg Cha−1 for Enset-tree, Enset-coffee-tree and Tree-coffee systems, respectively. The soil organic carbon (SOC) stocks accounted for 60–64% of the total carbon in the studied systems. Model validation results showed that long-term (10–40 years) simulated biomass C stocks were within the range of measured biomass C stocks for Enset-tree and Enset-coffee-tree systems, but significantly differed for the Tree-coffee system. The simulated soil and total C stocks were within the range of measured values for all the three systems. The CO2FIX model accurately predicted the SOC and total C stocks in the studied indigenous agroforestry systems, but the prediction of the biomass C stocks could be improved by acquiring more accurate input parameter values for running the model.

A Study on Water Hyacinth Purifying Effect on Different Levels of Eutrophic Water

In this experiment, water hyacinth presents a good purification effect in five kinds of eutrophic waters with initial total nitrogen (TN) and total phosphorus (TP) concentrations in between 8.34~20.45 mg/L and 0.78~1.51 mg/L. After two weeks of purification, TN and TP concentrations of eutrophic waters are reduced to 1.78~5.68 mg/L and 0.25~0.312 mg/L, and TN and TP removal rates are 72.22~78.65% and 67.95~79.34%. Water hyacinth’s TN removal rate decreases as TN initial concentration increases; TP removal rate increases as TP initial concentration increases. Water hyacinth’s average total biomass in eutrophic water has increased by 0.944~1.084 kg/m2, and the average bio-dry-weight has increased by 0.0470~0.0547 kg/m2. The average total biomass and average bio-dry-weight of water hyacinth increase as the eutrophication deepens.

Deep-sea nematode assemblages from a commercially important polymetallic nodule area in the Central Indian Ocean Basin

The Central Indian Ocean Basin (CIOB) is an important area for prospective mining for polymetallic nodules. However, little is known about the biodiversity or community structure of abyssal benthic assemblages in the area. The aim of this study was to investigate nematode assemblages inhabiting nodule fields in the CIOB in terms of species composition, diversity, density, biomass, size spectra and sex ratio. Samples were collected by box corer from a depth of 5000–5100 m during the 39th cruise of RV Akademik Boris Petrov in 2009. In total, 1066 individuals were examined from 4 stations and 16 samples. The total average density of nematodes recorded in the CIOB was considerably lower than reported from other deep-sea regions (27.17 ± 2.7 inds/10 cm2). Nematode diversity was comparable with that of other deep-sea regions and the composition of the dominant taxa was typical for oceanic basins. A total of 284 morphotypes belonging to 113 genera and 30 families were identified. Chromadoridae (29.6%), Xyalidae (19.3%), Oxystominidae (6.6%) and Desmoscolecidae (5.0%) were the dominant families. Among the genera, Acantholaimus (23.2%), Halalaimus (5.7%), Desmoscolex (4.8%), Theristus (3.5%) and Daptonema (3.4%) were the most numerous. The majority of specimens had a body length in the range of 1000–1500 µm, which is also in accordance with other deep-sea studies. Females were three times more abundant than males at all CIOB stations. Average total nematode biomass (52.39 ± 10.0 mg/m2) was comparable with macrofauna biomass from the same area.

Phytoplankton in an ecological status assessment of the vendace-type Lake Dejguny (northeastern Poland)

Abstract The aim of the study was to perform an ecological status assessment based on the phytoplankton in the vendace-type Lake Dejguny in accordance with the requirements of the Water Framework Directive. The phytoplankton analyses were conducted during three growth seasons in 2006, 2007, and 2008. The phytoplankton multimetric Phytoplankton Metric for Polish Lakes (PMPL) was used to assess the lake’s ecological status. The average total biomass of phytoplankton ranged from 1.6 to 3.9 mg dm-3, while the average biomass of Cyanoprokaryota ranged from 0.4 to 1.4 mg dm-3, with the minimum noted in 2008. The phytoplankton assemblages were dominated mainly by filamentous Cyanoprokaryota and pennate Bacillariophyceae in 2006 and 2008, or exclusively by pennate Bacillariophyceae in 2007. The relatively low total biomass and Cyanoprokaryota biomass, as well as seasonal phytoplankton dynamics with the dominant taxa of Tabellaria flocculosa, Dinobryon sociale, and D. divergens confirmed the lake’s mesotrophic state and some of the features of reference conditions in this lake, whereas the predominance of filamentous species Planktothrix agardhii and Planktolyngbya limnetica was characteristic of eutrophic conditions. However, a clear tendency towards progressive eutrophication stemming from the significant domination of filamentous Cyanoprokaryota was observed, and according to the PMPL the assessment indicated that Lake Dejguny had a good ecological status in 2006 and 2007 and even a high one in 2008.

Redistribution of forest carbon caused by patch blowdowns in subalpine forests of the Southern Rocky Mountains, USA

AbstractPatch blowdowns varying in size from 0.1 to 33 ha affected several areas in Rocky Mountain National Park, Colorado, USA, during the winter of 2011–2012. These blowdowns resulted in substantial redistribution of forest carbon by snapping and uprooting trees, thereby increasing instream wood recruitment, recruitment of dead wood to the forest floor, and exposure of organic soil on uprooted tree plates. Estimates of carbon redistribution at five sites in Rocky Mountain National Park range as high as 308 Mg C/ha in high‐severity patches to 106 Mg C/ha in low‐severity patches, of which typically 10–30% is soil C and the remainder is downed wood. Masses of carbon redistributed from living to dead biomass at high‐severity sites represent a substantial portion of average total biomass in old‐growth subalpine forests in the region. Consequently, the potential for increasing frequency and/or severity of blowdowns under a warming climate represents a significant potential source of terrestrial carbon to the atmosphere. The majority of this carbon is in the form of downed wood that becomes a carbon source to the atmosphere, although interactions between downed wood and river processes can locally increase carbon storage in floodplain soil. Predictions of changes in precipitation and wind patterns, and associated changes in wildfire and insect infestation, suggest that blowdowns may become more common in future in the Southern Rockies, but the consequences for carbon dynamics depend on site‐specific interactions between blowdowns and other processes such as floodplain storage of organic matter.

Effects of whole-tree harvesting on growth of pine and spruce seedlings in southern Finland

The effects of harvesting logging residue on the survival and growth of planted Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst) seedlings and on number and growth of natural seedlings were studied at five sites in southern Finland. Trees were harvested either conventionally, i.e. harvesting only the stems, or harvesting all the aboveground tree biomass (WTH). One of the experiments had been planted with pine and four experiments with spruce 10 years ago. When the spruce experiments were analysed together, WTH had significantly increased the average number of planted seedlings, but had not affected basal area, stem volume or biomass of the planted seedlings. When both planted and natural seedlings were studied together, WTH significantly increased the average number of seedlings and the average total biomass of all tree species. In the pine experiment, WTH had no effect on stand or tree characteristics. In this study, within the first 10 years after reforestation, WTH did not have any negative effect in stand or tree characteristics that could be explained by nutrients removed with logging residue.

Some peculiarities of the population biology of the ghost shrimp Nihonotrypaea petalura (Stimpson, 1860) (Decapoda: Callianassidae) in coastal waters of Vostok bay, the Sea of Japan

In June 2012, some features of the population biology of the ghost shrimp Nihonotrypaea petalura were studied first for the Russian waters in sublittoral populations of the Vostok Bay (Peter the Great Bay, Sea of Japan). It was found that N. petalura formed aggregations of an average density of 9–19 ind./m2 at the depth of 0.2–3 m on rocky and mixed bottoms. The biomass of the aggregations was 15–27 g/m2 or 1–33% of the average total biomass of macrozoobenthos, which included animals of 48 taxa. The maximum depth of the shrimp burrows was 52 cm. The populations consisted of animals with body lengths of 17–63 mm. In the size-frequency distribution, two peaks in the number, attributed to the shrimps of 24–29 and 39–48 mm size groups, were observed. The ratio of males to females almost did not vary with size and remained in general close to 1: 0.9 for the surveyed shrimp populations. The local differences in the studied parameters of N. petalura from the Vostok Bay, as well as from other areas of the range, are discussed in relation to features of the habitation of these animals that living in different biotopes.

Effects of soil flooding on photosynthesis and growth of Zea mays L. seedlings under different light intensities

Soil flooding is one of the major abiotic stresses that repress maize ( Zea mays L.) growth and yield, and other environmental factors often influence soil flooding stress. This paper reports an experimental test of the hypothesis that light intensity can influence the responses of maize seedlings to soil flooding. In this experiment, maize seedlings were subjected to soil flooding at the two-leaf stage under control light (600 µmol m -2 s -1 ) or low light (150 µmol m -2 s -1 ) conditions. Under control light growth conditions, the average photosynthetic rate (PN), transpiration rate (E) and water use efficiency (WUE) were 70, 26 and 59%, respectively, higher in non-flooded than in flooded seedlings; and the average chlorophyll a (Chl a), chlorophyll b (Chl b) and Chl a+b were 31, 42 and 34%, respectively, higher in non-flooded than in flooded seedlings; and the average belowground biomass and total biomass were 52 and 34%, respectively, higher in non-flooded than in flooded seedlings. There was a slight decrease of seedling biomass in six days flooded seedlings under low light growth conditions. The effects of flooding on photosynthetic, seedling growth and shoot/root ratio were more pronounced under control light growth conditions than under low light growth conditions, which indicate that even for maize which is a C4 plant, relatively high light intensity still aggravated soil flooding stress, while low light growth condition mitigated soil flooding stress, and suggests that light effects should be considered when we study maize responses to soil flooding.

Effect of N-acetylcysteine against biofouling of reverse osmosis membrane

The influence of (1.5 mg/mL) of N-acetylcysteine (NAC), a non-antibiotic, mucolytic agent, on the biofouling of a reverse osmosis (RO) membrane by a multi-species culture (four environmental strains) of biofilm forming bacteria was studied. NAC was found to considerably suppress the formation of the biofilm on the RO membrane. The inhibitory effect of NAC on biofilm formation was verified by image based studies. There was over a 70% reduction in biofilm surface coverage when grown in the presence of NAC. Similarly, the average thickness and total biomass content of the biofilm formed in presence of NAC were significantly less than those of the control. These results suggest that NAC could be a potential agent for the control of biofouling of a RO membrane. However, the chemical stability, potential toxicity and consistent performance of NAC in the field will have to be further investigated for optimization of its use on a field scale.

Colossal Aggregations of Giant Alien Freshwater Fish as a Potential Biogeochemical Hotspot

The ubiquity and fascinating nature of animal aggregations are widely recognised. We report here consistent and previously undocumented occurences of aggregations of a giant alien freshwater fish, the Wels catfish (Silurus glanis). Aggregative groups were on average composed of 25 (±10 SD, ranging from 15 to 44) adults with estimated average total biomass of 651 kg (386 – 1132) and biomass density of 23 kg m−2 (14 – 40). Aggregations always occurred within the same location. No foraging, reproductive or anti-predator behaviour were observed during the aggregations. A mass-balance model estimated that these colossal aggregations of an alien species can locally release, through excretion only, up to 70 mg P m−2 h−1 and 400 mg N m−2 h−1, potentially representing the highest biogeochemical hotspots reported in freshwater ecosystems and another unexpected ecological effect of alien species.

Growth response of <i>Pterocarpus soyauxii</i> and <i>Lophira alata</i> seedlings to host soil mycorrhizal inocula in relation to land use types

Deficiency in mycorrhizal inoculum in soils due to land use types (LUT) can be alleviated by inoculum addition. Inoculum effects may depend both on quantity and on quality of inoculum applied. A greenhouse bioassay was carried out to determine the effect of host soil mycorrhizal inoculum on mycorrhizal colonization, carbon allocation and partitioning of seedlings of two native timber species of Cameroon humid forest, raised on surface soils (0-20 cm) collected from early secondary forests, LUT derived from slash-and-burn agriculture and selective logging. Host soil mycorrhizal inoculum was collected from the root zones of con-specific tree species. Mycorrhizal inoculation effect (MIE) was estimated as percent difference of average total biomass between seedlings grown on inoculated and non-inoculated soils. Six months-old seedlings of Pterocarpus soyauxii and Lophira alata were mainly colonized by members of the Glomaceae and Gigasporaceae, respectively, as shown by molecular typing. They generally performed poorly in soils with indigenous inoculum. But addition of soil inoculum from P. soyauxii trees favored nodulation, significantly increased mycorrhizal colonization and total biomass but decreased root-to-shoot ratios, resulting in large and positive MIE, irrespective of LUT. ln contrast, host soil inoculum of L. alata did not affect fractional mycorrhizal colonization but significantly increased total biomass, resulted in high carbon allocation to roots, in low and sometimes negative MIE. Therefore, seedlings' responses to mycorrhizal inoculum depend on host soil inoculum and that could be critical for successful rejuvenation of tropical trees. Key words. Arbuscular mycorrhiza-host soil inoculum-Iand use types- Pterocarpus soyauxii-Lophira alata -Cameroon

Study on modules biomass structure of Epimedium acuminatum in different habitats

To study the biomass structure of Epimedium acuminatum Franch in the different ecological environments for the development and protection. Through the scientific investigation in four typical habitats, the sampling spots were set up, the functional modules' biomass structure and relationship of E. acuminatum were researched. The average of rhizome, as the largest biomass, and the average total biomass had the same pattern: the open areas of forest edge > shrub lumber > shrub-weed > stream drains. The ratio of the functional modules' biomass had different rates under different habitat conditions. By analyzing and combining investigation, the aerial part of E. acuminatum in the shrub-weed were comparative advantage, and the roots of nutrient accumulation of E. acuminatum in the open areas of forest edge were the highest efficient. Under different ecological condition, the distribution of water metabolism was different strategies. In the open areas of forest edge, E. acuminatum growing well, followed by shrub-weed. These two habitats are the ideal ecological environments while the rhizome or the whole plant used as medicine, but also the protection of E. acuminatum.

Quantificação de biomassa e estimativa de estoque de carbono em uma capoeira da Zona da Mata Mineira

Este estudo teve como objetivo quantificar os estoques de volume, de biomassa total com casca e de carbono em um fragmento de Floresta Estacional Semidecidual em estádio secundário médio (capoeira) na Zona da Mata mineira, no Município de Viçosa, MG. Para a conversão de volume em biomassa foram obtidas estimativas de densidade básica das 10 espécies de maior valor de importância (VI). O estoque de carbono foi determinado considerando-se que a biomassa seca contém cerca de 50% de carbono. Foram contabilizadas 31 espécies arbóreas, distribuídas em 29 gêneros e 21 famílias. A biomassa total média das árvores foi de 38,99 t.ha-1, o que correspondeu a um estoque de carbono de 19,50 ± 8,08 tC.ha-1. O valor encontrado foi considerado baixo quando comparado com o de outros estudos. Uma explicação para isso podem ser as influências sofridas pelo uso anterior da área e a ação de efeitos de borda na capoeira, o que contribuiu para a menor estocagem de biomassa e de carbono. As estimativas obtidas para a capoeira podem ser usadas como subsídios para a elaboração de projetos de florestamento/reflorestamento do Mecanismo de Desenvolvimento Limpo.

Aboveground biomass in three Sonoran Desert communities: Variability within and among sites using replicated plot harvesting

Total aboveground biomass (TAGB) values are reported for the first time for the Sonoran Desert. Harvesting of replicated plots in three sites differing in geomorphology and vegetation structure allowed the statistical measurement of spatial variability within and among sites. Linear, power log-transformed, and power non-linear regressions were used to relate TAGB with plant metrics. Canopy volume explained the largest proportion of TAGB variance ( r 2 = 0.74–0.94) in the three models. All models were highly significant, but the non-linear was more robust, had a better distribution of residuals, and did not require data back-transforming, allowing the accurate estimation of biomass at the plot level using simple measurements of vegetation. TAGB ranged from 6.99 Mg ha −1 (Plains) to 29.24 Mg ha −1 (Arroyos) in the desertscrub, and was intermediate in the thornscrub (Hillsides: 13.03 Mg ha −1). Within-site variability of TAGB was highest in the Plains and lowest in the Hillsides. The weighted mean AGB was 16 Mg ha −1. Assuming a 1:1 root:shoot ratio, average total biomass could be 32 Mg ha −1. This remarkable value sets the Sonoran Desert as a potential reservoir of up to 4.4% of the total world deserts plant biomass in less than 1% of the deserts’ global area.

Métodos de manejo de aveia preta para evitar sua ressurgência como planta daninha em trigo

A aveia preta é a cultura de cobertura de inverno importante no sul do Brasil. Entretanto, a aveia preta, do mesmo modo que o azevém anual, é uma planta daninha em culturas comerciais de inverno. Dois experimentos em blocos casualizados foram conduzidos na Embrapa Trigo, em Passo Fundo, Rio Grande do Sul (RS), para estudar métodos de manejo de aveia preta em dois estádios de desenvolvimento, antese e grão leitoso, que evitem a transformação dessa espécie em planta daninha, em trigo cultivado em sucessão com soja. As parcelas tiveram área útil de 60m². Nove métodos de manejo foram estudados: dessecação; rolagem e dessecação; fenação; ensilagem; roçada; trituração; rolagem, mediante uma operação com rolo faca; gradagem; colheita mecânica de grãos. A biomassa média acumulada na antese foi de 5.016kg MS ha-1 e em grão leitoso, de 6.050kg MS ha-1. Durante o verão, a soja não foi afetada pelos métodos de manejo de aveia e teve produtividade média de 2.080kg ha-1. Na safra de inverno do ano seguinte, os métodos de manejo aplicados na antese tiveram produtividade média de grãos de trigo de 2.472kg ha-1, e a densidade de espigas foi de 355 espigas m-2, nas parcelas que foram dessecadas antes da semeadura da cultura de trigo, e 836kg ha-1 e 225 espigas m-2, nas parcelas sem dessecação. Nos manejos aplicados no estádio de grão leitoso, a produtividade média foi de 1.733kg ha-1, com densidade de espigas de 334 espigas m-2. Nas parcelas sem dessecação, a cultura de trigo foi totalmente dominada pelas plantas espontâneas de aveia, resultantes dos métodos de manejo aplicados no inverno anterior. Métodos de manejo da aveia exclusivamente mecânicos, em qualquer estádio de desenvolvimento da cultura, pode transformar essa espécie em planta daninha, nos cultivos de inverno subsequentes. Esse problema é evitado com dessecação até a antese, pois, depois desse estádio, nenhum método de manejo testado foi capaz de evitar a maturação fisiológica de sementes de aveia, tornando essa espécie uma planta daninha potencial para as safras de inverno subsequentes e obrigando a dessecação das plantas emergidas antes da semeadura de culturas comerciais.

Hikers Impact on the North Fork of the Virgin River, Zion National Park, Utah

The research studied the benthic algal cyanobacterial community and ecological and physical characteristics to determine whether recreational hiking impacts the Virgin River in Zion National Park, Utah. Sampling occurred on 10 August 2001 of three cobblestones from 11 different riffle locations. The null hypothesis is the algal community will change in assemblage structure and function along a hikers gradient. This hypothesis predicts that lower or no visitor use sites will have lower algal species diversity, average cell biovolume, cell density, total biomass, chlorophyll a, AFDM, and ash weight and percentage. There were 99 benthic algal and cyanobacteria species identified from the Virgin River. The benthic flora and ecological/physical parameters were examined to assess the impact of hiking. Canonical correspondence analyses of the species data separated sites into 2-groups (impacted and none to low impact). The first and second axes of the ecological/physical variables explained 67% of the variation. The average cell biovolume and species diversity were positively aligned to the first axis, while cell density was slightly negatively aligned. The data suggests the ecological threshold had been reached lowering the relative abundance of diatoms and increasing cyanobacteria contribution. Further research needs to be accomplished determine exact cause.

From a tree to a stand in Finnish boreal forests: Biomass estimation and comparison of methods

There is an increasing need to compare the results obtained with different methods of estimation of tree biomass in order to reduce the uncertainty in the assessment of forest biomass carbon. In this study, tree biomass was investigated in a young 30-year-old Scots pine (Pinus sylvestris) and a mature 130-year-old mixed Norway spruce (Picea abies)-Scots pine stand located in southern Finland (61°50' N, 24°22' E). In particular, a comparison of the results of different estimation methods was conducted to assess the reliability and suitability of their applications. For the trees in the studied mature stand, the annual stem biomass increment increased following a sigmoid equation. The fitted curves reached the maximum level (from about 1 kg yr for understorey to 7 kg yr for dominant tree) in the studied stand when the trees were 100 years old. The results revealed a substantial difference in tree stand biomass among estimations made by different methods. For instance, at stand level, on the basis of the above-ground tree biomass (170.8 Mg ha) estimated by partial harvesting method, it had a higher estimate (+10%) based on the dry mass of selected understorey, medium and dominant trees as the sample trees, but a lower estimate (–18%) by the means of the allometric functions which were established based on the tree data in Sweden. In the studied mature stand, lichen biomass on the trees was estimated at 1.63 Mg ha with more than half of the biomass being on dead branches, and litter lichen biomass on the ground was about 0.09 Mg ha. Based on a data set compiled from the studies previously published, a meta-analysis was conducted to compare the tree biomass accumulation in southern Finland with that in the boreal region (58.00-62.13 oN, 14-34 oE, ≤ 300 m a.s.l.). The results showed that in this region the average total tree biomass was about 180 Mg ha with the range of 100 to 250 Mg ha at the age of 140 years in Norway spruce and Scots pine stands. The total tree biomass of two stands in the present study was at the average level at corresponding stages of age in this region.

Can spatial variation in epiphyte diversity and community structure be predicted from sampling vascular epiphytes alone?

AbstractAim Non‐vascular epiphytes have been largely ignored in studies examining the biotic and abiotic determinants of spatial variation in epiphyte diversity. Our aim was to test whether the spatial patterning of species richness, biomass and community composition across geographic regions, among trees within regions, and among branches within trees is consistent between the vascular and non‐vascular components of the temperate rain forest flora.Location Coastal lowland podocarp‐broadleaved forests on the west coast of the South Island of New Zealand.Methods We collected single samples (30 × 25 cm) from 96 epiphyte assemblages located on the inner branches of 40 northern rata (Metrosideros robusta) trees. For each sample, branch characteristics such as branch height, branch diameter, branch angle, branch aspect, and minimum and maximum epiphyte mat depth were recorded. The biomass for each individual epiphyte species was determined.Results Northern rata was host to a total of 157 species, comprising 32 vascular and 125 non‐vascular species, with liverworts representing 41% of all species. Within epiphyte mats, the average total organic biomass of 3.5 kg m−2 of branch surface area consisted largely of non‐living biomass and roots. Vascular and non‐vascular epiphytes showed strikingly different spatial patterns in species richness, biomass and composition between sites, among trees within sites, and among branches within trees, which could not be explained by the branch structural characteristics we measured. The two plant groups had no significant association in community composition (r = 0.04, P = 0.08). However, the species richness of vascular plant seedlings was strongly linked to the presence/absence of lichens.Main conclusions Non‐vascular plants contributed substantially to the high species richness and biomass recorded in this study, which was comparable to that of some tropical rain forests. High variability in community composition among epiphyte mats, and very low correlation with any of the environmental factors measured possibly indicate high levels of stochasticity in seed or spore colonization, establishment success or community assembly among branches in these canopy communities. Although we found some evidence that vascular plant seedling establishment was linked to the presence of lichens and the biomass of non‐living components in the epiphyte mats, there was no correlation in the spatial patterning or determinants of species richness between non‐vascular and vascular plants. Consequently, variation in total epiphyte biodiversity could not be predicted from the measurement of vascular plant diversity alone, which highlights the crucial importance of sampling non‐vascular plants when undertaking epiphyte community studies.