Growth dynamics of fine roots in a coniferous fern forest site close to Forsmark in the central part of Sweden

Energy Technology Data Exchange (ETDEWEB)

Persson, Hans; Stadenberg, Ingela (SLU, Dept. of Ecology and Environmental Research, Uppsala (Sweden))

2007-12-15

The seasonal growth dynamics of live and dead roots for trees and the field layer species (g/m2, varying diameter fractions) and live/dead ratios were analysed at a fresh/moist coniferous fern forest site close to the nuclear power plant at Forsmark in the central eastern parts of Sweden. The changes in depth distribution of fine roots were observed at depth intervals of the top humus horizon down to 40 cm in the mineral soil profile. The bulk of living fine roots of trees (< 1 mm in diameter) were found in the mineral soil horizon the total profile down to 40 cm of the mineral soil, where 89, 82, 83 and 89% of the total amount in the whole profile were found. The upper 2.5 cm part of the humus layer contained 83, 81, 100 and 100% of all roots of the humus layer on the four different sampling occasions. High amounts of living fine roots were found in the upper 10 cm of the mineral soil horizon viz. 84, 76, 91 and 69% of the total mineral soil layer. Consequently, both the top soil horizons of the humus and the mineral soil layers were heavily penetrated by living fine roots. The highest proportion of living fine roots was found in the top 2.5 cm of the humus layer. Accordingly, the live/dead ratio of fine roots (< 1 mm in diameter) decreased from the top of the humus layer to the lower part of mineral soil horizon from 8.0-0.3, 0.8-0.2, 4.4-0.4 and 3.3-0.7 (g g-1) for the four sampling occasions, respectively. We concluded that the decrease in the live/ dead ratio was related to decreased vitality with depth of the fine roots in the soil profile. The highest live/dead ratio was found in the upper 2.5 cm of the humus layer for both the tree and field-layer species. This distribution pattern was most evident for tree fine roots < 1 mm in diameter. The mean fine-root biomass (live tissue < 1 mm in diameter) of tree species for the total profile varied on the four sampling occasions between 317, 113, 139 and 248 g m-2. The related fine root necromass (dead tissue

Behavior of 7Be and 210Pb deposited via rainwater on a coniferous forest, a broad-leaved forest, and grassland

International Nuclear Information System (INIS)

Osaki, S.; Sugihara, S.; Maeda, Y.; Osaki, T.

2007-01-01

Fall water, stem flow water and falling litter in a coniferous forest (C. japonica) and a broad-leaved forest (L. edulis), and rainwater on a grassland near the forests were collected, and their 7 Be and 210 Pb contents were measured. The average residence times of 7 Be and 210 Pb in the forest crowns were calculated from the balances of their radionuclides, those in the forest crown of C. japonica were 88 days for 7 Be and 9.2 years for 210 Pb, and those in the forest crown of L. edulis were 52 days and <1 year, respectively. (author)

Calibration of the L-MEB model over a coniferous and a deciduous forest

DEFF Research Database (Denmark)

Grant, Jennifer P.; Saleh-Contell, Kauzar; Wigneron, Jean-Pierre

2008-01-01

In this paper, the L-band Microwave Emission of the Biosphere (L-MEB) model used in the Soil Moisture and Ocean Salinity (SMOS) Level 2 Soil Moisture algorithm is calibrated using L-band (1.4 GHz) microwave measurements over a coniferous (Pine) and a deciduous (mixed/Beech) forest. This resulted...

Private and public incomes in dehesas and coniferous forests in Andalusia, Spain

Science.gov (United States)

Paola Ovando; Pablo Campos; Jose L. Oviedo; Alejandro Caparrós

2015-01-01

We apply an ecosystem accounting system to estimate the total social income accrued from private and public products in a group of agroforestry farms in Andalusia (Spain). We provide bio-physical and economic indicators for two contrasting farm types, a sub-group of 15 publicly owned coniferous forests and a sub-group of 24 privately owned dehesa farms. Total social...

Influence of soil fungi (basidiomycetes) on the migration of Cs 134 + 137 and Sr 90 in coniferous forest soils

International Nuclear Information System (INIS)

Roemmelt, R.; Hiersche, L.; Schaller, G.; Wirth, E.

1990-01-01

During the first three years after the Chernobyl event high Cs 134 + 137 activities in fruitbodies of basidiomycetes have been measured. A decline of activities with time has not yet been observed. The activities are considerably higher compared to agricultural products from the same area. In order to study the movement of radiocesium in coniferous forest sites, the activities in soil, fungi, and plants have been measured. Based on these results a model to describe the cesium cycling in coniferous forest ecosystems is proposed with special emphasis on the influence of soil fungi and plants on the migration of cesium. As measurements of Sr 90 in forest ecosystems are rare this nuclide has been included in the investigations. (author)

Substantial secondary organic aerosol formation in a coniferous forest: observations of both day- and nighttime chemistry

OpenAIRE

A. K. Y. Lee; J. P. D. Abbatt; W. R. Leaitch; S.-M. Li; S. J. Sjostedt; S. J. Sjostedt; J. J. B. Wentzell; J. Liggio; A. M. Macdonald

2016-01-01

Substantial biogenic secondary organic aerosol (BSOA) formation was investigated in a coniferous forest mountain region at Whistler, British Columbia. A largely biogenic aerosol growth episode was observed, providing a unique opportunity to investigate BSOA formation chemistry in a forested environment with limited influence from anthropogenic emissions. Positive matrix factorization of aerosol mass spectrometry (AMS) measurement identifie...

Evaluation of meteorological parameters over a coniferous forest in a single-column chemistry-climate model

NARCIS (Netherlands)

Ganzeveld, L.N.; Klemm, O.; Rappenglück, B.; Valverde-Canossa, J.

2006-01-01

The simulated micrometerology by a single-column chemistry-climate model (SCM) has been evaluated by comparison with BEWA2000 field campaign measurements over a coniferous forest, July-August 2001. This comparison indicates the limitations in the representation of the SCM's micrometeorological

Analyzing the ecosystem carbon dynamics of four European coniferous forests using a biogeochemistry model

NARCIS (Netherlands)

Churkina, G.; Tenhunen, J.; Thornton, P.; Falge, E.; Elbers, J.A.; Erhard, M.; Grünwald, T.; Kowalski, A.; Rannik, Ü.; Sprinz, D.

2003-01-01

This paper provides the first steps toward a regional-scale analysis of carbon (C) budgets. We explore the ability of the ecosystem model BIOME-BGC to estimate the daily and annual C dynamics of four European coniferous forests and shifts in these dynamics in response to changing environmental

Susceptible conditions for debarking by deer in subalpine coniferous forests in central Japan

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Hayato Iijima

2015-12-01

Full Text Available Background: Recently, deer have expanded their distribution to higher altitude ranges including subalpine forests. However, culling deer and construction of deer fence in subalpine forests are difficult because of steep slopes and complex topography. Thus it is necessary to clarify the factors which are associated with debarking by deer for the effective protection of subalpine forests. In this study, we examined which factors are associated with debarking by sika deer (Cervus nippon in subalpine coniferous forests. Methods: We conducted our survey in Minami-Alps National Park, central Japan. We established 24 10 m× 40 m plots and surveyed the occurrence of debarking on saplings >30 cm in height and 3 cm in DBH, as well as sapling density within each plot. Minimum distances to nearest grassland of plots were calculated (tentatively assuming grassland would attract deer and would cause high debarking pressure in the surrounding subalpine forests. Results: The mean percentage of debarked live saplings was higher than that of live trees. The mean percentage of debarked saplings which had already died was 81.6 %. Debarking of saplings increased with lower elevation, taller sapling size, and marginally increased near grassland. Sapling density was lower in plots with low basal area of conspecific trees near grassland and differed among species. Sapling density marginally decreased with decreasing elevation and increasing stand tree density. Debarking of trees was positively related to small DBH and low elevation, and marginally increased near grassland and differed among species. Conclusions: Our results suggest that tall saplings in subalpine forests of low elevation or near subalpine grassland were susceptible to debarking by deer and monitoring of these areas may permit the early detection of the impacts of deer in subalpine coniferous forests. Keywords: Abies, Cervus nippon, Debarking, Grassland, Picea, Sapling density, Subalpine region

rFerns: An Implementation of the Random Ferns Method for General-Purpose Machine Learning

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Miron B. Kursa

2014-11-01

Full Text Available Random ferns is a very simple yet powerful classification method originally introduced for specific computer vision tasks. In this paper, I show that this algorithm may be considered as a constrained decision tree ensemble and use this interpretation to introduce a series of modifications which enable the use of random ferns in general machine learning problems. Moreover, I extend the method with an internal error approximation and an attribute importance measure based on corresponding features of the random forest algorithm. I also present the R package rFerns containing an efficient implementation of this modified version of random ferns.

Scenario Modeling of Thermal Influence from Forest Fire Front on a Coniferous Tree Trunk

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Baranovskiy Nikolay V.

2016-01-01

Full Text Available Scenario research results of heat transfer and tissue damage in three-layered tree trunk influenced by heat flux from forest fire are presented. The problem is solved in two-dimensional statement in polar coordinates. The typical range of influence parameters (heat flux from forest fire front, trunk radius, coniferous species, air temperature, duration of exposure and distance from fire line is considered. Temperature distributions in different moments of time are obtained. Condition of tree damage by forest fire influence is under consideration in this research. Information summarized using tables with scenario and fire consequences results.

Coniferous Canopy BRF Simulation Based on 3-D Realistic Scene

Science.gov (United States)

Wang, Xin-yun; Guo, Zhi-feng; Qin, Wen-han; Sun, Guo-qing

2011-01-01

It is difficulties for the computer simulation method to study radiation regime at large-scale. Simplified coniferous model was investigate d in the present study. It makes the computer simulation methods such as L-systems and radiosity-graphics combined method (RGM) more powerf ul in remote sensing of heterogeneous coniferous forests over a large -scale region. L-systems is applied to render 3-D coniferous forest scenarios: and RGM model was used to calculate BRF (bidirectional refle ctance factor) in visible and near-infrared regions. Results in this study show that in most cases both agreed well. Meanwhiie at a tree and forest level. the results are also good.

Dry coniferous forest restoration and understory plant diversity: The importance of community heterogeneity and the scale of observation

Science.gov (United States)

Erich Kyle Dodson; David W. Peterson

2010-01-01

Maintaining understory plant species diversity is an important management goal as forest restoration and fuel reduction treatments are applied extensively to dry coniferous forests of western North America. However, understory diversity is a function of both local species richness (number of species in a sample unit) and community heterogeneity (beta diversity) at...

Soil CO2 efflux among four coniferous forest types of Kashmir Himalaya, India.

Science.gov (United States)

Dar, Javid Ahmad; Ganie, Khursheed Ahmad; Sundarapandian, Somaiah

2015-11-01

Soil CO2 efflux was measured in four different coniferous forest types (Cedrus deodara (CD), Pinus wallichiana (PW), mixed coniferous (MC), and Abies pindrow (AP)) for a period of 2 years (April 2012 to December 2013). The monthly soil CO2 efflux ranged from 0.8 to 4.1 μmoles CO2 m(-2) s(-1) in 2012 and 1.01 to 5.48 μmoles CO2 m(-2) s(-1) in 2013. The soil CO2 efflux rate was highest in PW forest type in both the years, while it was lowest in MC and CD forest types during 2012 and 2013, respectively. Soil temperature (TS) at a depth of 10 cm ranged from 3.8 to 19.4 °C in 2012 and 3.5 to 19.1 °C in 2013 in all the four forest types. Soil moisture (MS) ranged from 19.8 to 58.6% in 2012 and 18.5 to 58.6% in 2013. Soil CO2 efflux rate was found to be significantly higher in summer than the other seasons and least during winter. Soil CO2 efflux showed a significant positive relationship with TS (R2=0.52 to 0.74), SOC% (R2=0.67), pH (R2=0.68), and shrub biomass (R2=0.51), whereas, only a weak positive relationship was found with soil moisture (R2=0.16 to 0.41), tree density (R2=0.25), tree basal area (R2=0.01), tree biomass (R2=0.07), herb biomass (R2=0.01), and forest floor litter (R2=0.02). Thus, the study indicates that soil CO2 efflux in high mountainous areas is greatly influenced by seasons, soil temperature, and other environmental factors.

Restoring Native Forest Understory: The Influence of Ferns and Light in a Hawaiian Experiment

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Robert Shallenberger

2013-03-01

Full Text Available Ecological restoration is an increasingly important component of sustainable land management. We explore potential facilitative relationships for enhancing the cost-effectiveness of restoring native forest understory, focusing on two factors: (1 overstory shade and (2 possible facilitation by a fern (Dryopteris wallichiana, one of few native colonists of pasture in our montane Hawaiˈi study system. We planted 720 understory tree seedlings and over 4000 seeds of six species under six planting treatments: a full factorial combination of low, medium and high light, situating plantings in either the presence or absence of a mature fern. After three years, 75% of outplanted seedlings survived. Seedling survivorship was significantly higher in the presence of a fern (79% vs. 71% without a fern and in medium and low light conditions (81% vs. 64% in high light. Relative height was highest at low to medium light levels. After 2.2 years, 2.8% of the planted seeds germinated. We observed no significant differences in seed germination relative to light level or fern presence. Analyzing several approaches, we found nursery germination of seeds followed by outplanting ca. 20% less costly than direct seeding in the field. This study opens new questions about facilitation mechanisms that have the potential to increase the extent and effectiveness of restoration efforts.

Epiphytic ferns in swamp forest remnants of the coastal plain of southern Brazil: latitudinal effects on the plant community

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Letícia S. Machado

Full Text Available ABSTRACT Community structure and spatial distribution of epiphytic ferns in swamp forest remnants along the coastal plain of the state of Rio Grande do Sul were analyzed. A total of 440 trees were sampled in fifty-seven 10 x 10 m plots. Each phorophyte was divided into five ecological zones (strata, where all species of epiphytic ferns were recorded. A total of 34 species representing 18 genera in six families were recorded. Polypodiaceae was the most represented family with 17 species, and Microgramma vacciniifolia had the highest epiphytic importance value. Characteristic holoepiphyte was the predominant ecological category, representing 70 % of the species. Ordination analysis showed a gradual change in floristic composition between ecological zones with richness differing significantly between strata. We observed that with increasing latitude there was a decrease in mean temperature and total rainfall, but an increase in frosts. These climatic and phytogeography changes result in a reduction in species richness and a change in the structure of epiphytic fern communities in a north-to-south direction. The importance of swamp forest remnants of the coastal plain to the diversity of epiphytic ferns is discussed.

The extent of immission damage to coniferous forests in the GDR around the year 1985

International Nuclear Information System (INIS)

Schuster, E.

1991-01-01

The economic effects of air pollution extend to the economic result of forestry and also directly to the state of forests; the latter damage includes loss of supplies, growth and unsuitability for felling and the adverse effect on forests as a place for rest and recreation. In this publication, results of calculations on the extent of this damage to the coniferous forests of the former DDR (differentiated according to spruce and pine and to the degree of damage) are submitted. The knowledge of the amount of this damage is of economic and forestry policy interest and it is gaining increasing trade importance. (orig.) [de

Seasonal changes in camera-based indices from an open canopy black spruce forest in Alaska, and comparison with indices from a closed canopy evergreen coniferous forest in Japan

Science.gov (United States)

Nagai, Shin; Nakai, Taro; Saitoh, Taku M.; Busey, Robert C.; Kobayashi, Hideki; Suzuki, Rikie; Muraoka, Hiroyuki; Kim, Yongwon

2013-06-01

Evaluation of the carbon, water, and energy balances in evergreen coniferous forests requires accurate in situ and satellite data regarding their spatio-temporal dynamics. Daily digital camera images can be used to determine the relationships among phenology, gross primary productivity (GPP), and meteorological parameters, and to ground-truth satellite observations. In this study, we examine the relationship between seasonal variations in camera-based canopy surface indices and eddy-covariance-based GPP derived from field studies in an Alaskan open canopy black spruce forest and in a Japanese closed canopy cedar forest. The ratio of the green digital number to the total digital number, hue, and GPP showed a bell-shaped seasonal profile at both sites. Canopy surface images for the black spruce forest and cedar forest mainly detected seasonal changes in vegetation on the floor of the forest and in the tree canopy, respectively. In contrast, the seasonal cycles of the ratios of the red and blue digital numbers to the total digital numbers differed between the two sites, possibly due to differences in forest structure and leaf color. These results suggest that forest structural characteristics, such as canopy openness and seasonal forest-floor changes, should be considered during continuous observations of phenology in evergreen coniferous forests.

Medicinal Plants in the Broad-Leaf Mixed Coniferous Forest of Tshothang Chiwog, Bhutan: Floristic Attributes, Vegetation Structure, Ethnobotany, and Socioeconomic Aspects

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Ngawang Jamba

2018-01-01

Full Text Available The Himalayan Kingdom of Bhutan, located in one of the global biodiversity hotspots, is endowed with abundant floral wealth, including a wide array of medicinal plants (MPs. However, over-exploitation of these resources is widespread, and only a few studies have assessed the richness and diversity of Bhutanese forests and in particular about the MP resources. A vegetation survey was conducted in Tshothang Chiwog, south-eastern Bhutan to characterize the floristic structure of the broad-leaf mixed coniferous forests with a special focus on MPs. A questionnaire survey involving 40 farmers was also conducted to assess the ethnobotanical and socioeconomic aspects of MP extraction. A total of 157 plant species (38 trees, 19 shrubs, 85 herbs and ferns, and 15 climbers, representing 74 families and 137 genera were identified from the study area, of which 69 species (14 trees, 10 shrubs, 38 herbs and ferns, and seven climbers, belonging to 41 families and 69 genera were medicinally important. The most species-rich families of medicinal plants were: Asteraceae (eight spp., Apiaceae (four spp., Polygonaceae, Brassicaceae, Zingiberaceae, and Urticaceae (three species each. Herbaceous flora exhibited the highest diversity (Simpson diversity index, D = 0.97 and Shannon-Weiner index, H′ = 5.82, followed by trees and shrubs (D = 0.95 and 0.92 and H′ = 4.86 and 3.97, respectively. All but one herb showed abundance-to-frequency ratio (A/F ≥0.05, signifying a contagious distribution pattern (large aggregated distribution. Girth class distribution of trees followed an inverse J-shaped pattern. Results of the ethnobotanic study documented 55 MPs. MP collection, as reported by the interviewees, generally improved the socioeconomic status of the people of Tshothang Chiwog. Apart from improving the livelihood security of the local people, aspects relating to health care and culture are also important. Respondents were also concerned about the declining MP wealth

The effect of slight thinning of managed coniferous forest on landscape appreciation and psychological restoration

Science.gov (United States)

Takayama, Norimasa; Saito, Haruo; Fujiwara, Akio; Horiuchi, Masahiro

2017-12-01

We investigated the influence of slight thinning (percentage of woods: 16.6%, basal area: 9.3%) on landscape appreciation and the psychological restorative effect of an on-site setting by exposing respondents to an ordinarily managed coniferous woodland. The experiments were conducted in an experimental plot in the same coniferous woodland in May (unthinned) and October 2013 (thinned). The respondents were the same 15 individuals for both experiments. Respondents were individually exposed to the enclosed plot and the forest-view plot within the same tent for 15 min. In both sessions, respondents were required to answer three questionnaires measuring their mood (Profile of Mood States), emotion (Positive and Negative Affect Schedule), and feeling of restoration (Restorative Outcome Scale) to investigate the psychological restorative effect before and after the experiment. They completed two other questionnaires measuring appreciation for the environment (Semantic Differential) and the restorative properties of the environment (Perceived Restorativeness Scale) following the experiments. We first analyzed the difference in landscape appreciation between the unthinned and thinned conditions. We did not find any statistical difference in appreciation for the environment (Semantic Differential) or the restorative properties of the environment (Perceived Restorativeness Scale); rather, we found that weather conditions had a primary influence on landscape appreciation. With respect to the psychological restorative effect, a two-way repeated analysis of valiance (ANOVA) revealed significant main effects for a selection of indices, depending on the presence or absence of thinning. However, multiple comparison analyses revealed that these effects seemed to be due to the difference in the experimental experience rather than the presence or absence of thinning. In conclusion, the effect of the slight thinning of the managed coniferous forest was too weak to be reflected in the

Carbon sequestration in managed temperate coniferous forests under climate change

Science.gov (United States)

Dymond, Caren C.; Beukema, Sarah; Nitschke, Craig R.; Coates, K. David; Scheller, Robert M.

2016-03-01

Management of temperate forests has the potential to increase carbon sinks and mitigate climate change. However, those opportunities may be confounded by negative climate change impacts. We therefore need a better understanding of climate change alterations to temperate forest carbon dynamics before developing mitigation strategies. The purpose of this project was to investigate the interactions of species composition, fire, management, and climate change in the Copper-Pine Creek valley, a temperate coniferous forest with a wide range of growing conditions. To do so, we used the LANDIS-II modelling framework including the new Forest Carbon Succession extension to simulate forest ecosystems under four different productivity scenarios, with and without climate change effects, until 2050. Significantly, the new extension allowed us to calculate the net sector productivity, a carbon accounting metric that integrates aboveground and belowground carbon dynamics, disturbances, and the eventual fate of forest products. The model output was validated against literature values. The results implied that the species optimum growing conditions relative to current and future conditions strongly influenced future carbon dynamics. Warmer growing conditions led to increased carbon sinks and storage in the colder and wetter ecoregions but not necessarily in the others. Climate change impacts varied among species and site conditions, and this indicates that both of these components need to be taken into account when considering climate change mitigation activities and adaptive management. The introduction of a new carbon indicator, net sector productivity, promises to be useful in assessing management effectiveness and mitigation activities.

Inorganic and organic nitrogen acquisition by a fern Dicranopteris dichotoma in a subtropical forest in South China.

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Xingliang Xu

Full Text Available The fern Dicranopteris dichotoma is an important pioneer species of the understory in Masson pine (Pinus massoniana forests growing on acidic soils in the subtropical and tropical China. To improve our understanding of the role of D. dichotoma in nitrogen (N uptake of these forests, a short-term (15N experiment was conducted at mountain ridge (MR, with low N level and mountain foot (MF, with high N level. We injected (15N tracers as (15NH4, (15NO3 or (15N-glycine into the soil surrounding each plant at both MR and MF sites. Three hours after tracer injection, the fern D. dichotoma took up 15NH4+ significantly faster at MF than at MR, but it showed significantly slower uptake of (15NO3- at MF than at MR. Consequently, (15NO3- made greater contribution to the total N uptake (50% to the total N uptake at MR than at MF, but (15N-glycine only contributed around 11% at both sites. Twenty-four hours after tracer injection, D. dichotoma preferred (15NH4+ (63% at MR, whereas it preferred (15NO3- (47% at MF. We concluded that the D. dichotoma responds distinctly in its uptake pattern for three available N species over temporal and spatial scales, but mainly relies on inorganic N species in the subtropical forest. This suggests that the fern employs different strategies to acquire available N which depends on N levels and time.

Fire Regime along Latitudinal Gradients of Continuous to Discontinuous Coniferous Boreal Forests in Eastern Canada

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Jeanne Portier

2016-09-01

Full Text Available Fire is the main disturbance in North American coniferous boreal forests. In Northern Quebec, Canada, where forest management is not allowed, the landscape is gradually constituted of more opened lichen woodlands. Those forests are discontinuous and show a low regeneration potential resulting from the cumulative effects of harsh climatic conditions and very short fire intervals. In a climate change context, and because the forest industry is interested in opening new territories to forest management in the north, it is crucial to better understand how and why fire risk varies from the north to the south at the transition between the discontinuous and continuous boreal forest. We used time-since-fire (TSF data from fire archives as well as a broad field campaign in Quebec’s coniferous boreal forests along four north-south transects in order to reconstruct the fire history of the past 150 to 300 years. We performed survival analyses in each transect in order to (1 determine if climate influences the fire risk along the latitudinal gradient; (2 fractionate the transects into different fire risk zones; and (3 quantify the fire cycle—defined as the time required to burn an area equivalent to the size of the study area—of each zone and compare its estimated value with current fire activity. Results suggest that drought conditions are moderately to highly responsible for the increasing fire risk from south to north in the three westernmost transects. No climate influence was observed in the last one, possibly because of its complex physical environment. Fire cycles are shortening from south to north, and from east to west. Limits between high and low fire risk zones are consistent with the limit between discontinuous and continuous forests, established based on recent fire activity. Compared to the last 40 years, fire cycles of the last 150–300 years are shorter. Our results suggest that as drought episodes are expected to become more frequent

Soil organic matter composition and quality across fire severity gradients in coniferous and deciduous forests of the southern boreal region

Science.gov (United States)

Miesel, Jessica R.; Hockaday, William C.; Kolka, Randall K.; Townsend, Philip A.

2015-06-01

Recent patterns of prolonged regional drought in southern boreal forests of the Great Lakes region, USA, suggest that the ecological effects of disturbance by wildfire may become increasingly severe. Losses of forest soil organic matter (SOM) during fire can limit soil nutrient availability and forest regeneration. These processes are also influenced by the composition of postfire SOM. We sampled the forest floor layer (i.e., full organic horizon) and 0-10 cm mineral soil from stands dominated by coniferous (Pinus banksiana Lamb.) or deciduous (Populus tremuloides Michx.) species 1-2 months after the 2011 Pagami Creek wildfire in northern Minnesota. We used solid-state 13C NMR to characterize SOM composition across a gradient of fire severity in both forest cover types. SOM composition was affected by fire, even when no statistically significant losses of total C stocks were evident. The most pronounced differences in SOM composition between burned and unburned reference areas occurred in the forest floor for both cover types. Carbohydrate stocks in forest floor and mineral horizons decreased with severity level in both cover types, whereas pyrogenic C stocks increased with severity in the coniferous forest floor and decreased in only the highest severity level in the deciduous forest floor. Loss of carbohydrate and lignin pools contributed to a decreased SOM stability index and increased decomposition index. Our results suggest that increases in fire severity expected to occur under future climate scenarios may lead to changes in SOM composition and dynamics with consequences for postfire forest recovery and C uptake.

The importance of micrometeorological variations for photosynthesis and transpiration in a boreal coniferous forest

DEFF Research Database (Denmark)

Schurgers, Guy; Lagergren, F.; Molder, M.

2015-01-01

the importance of vertical variations in light, temperature, CO2 concentration and humidity within the canopy for fluxes of photosynthesis and transpiration of a boreal coniferous forest in central Sweden. A leaf-level photosynthesis-stomatal conductance model was used for aggregating these processes to canopy...... abovecanopy and within-canopy humidity, and despite large gradients in CO2 concentration during early morning hours after nights with stable conditions, neither humidity nor CO2 played an important role for vertical heterogeneity of photosynthesis and transpiration....

A comparison of alpha and beta diversity patterns of ferns, bryophytes and macrolichens in tropical montane forests of southern Ecuador

OpenAIRE

Mandl, N A; Lehnert, M; Kessler, M; Gradstein, S R

2010-01-01

We present a first comparison of patterns of alpha and beta diversity of ferns, mosses, liverworts and macrolichens in neotropical montane rainforests, and explore the question whether specific taxa may be used as surrogates for others. In three localities in southern Ecuador, we surveyed terrestrial and epiphytic species assemblages in ridge and slope forests in 28 plots of 400 m² each. The epiphytic habitat was significantly richer in ferns, liverworts, and macrolichens than the terrestrial...

Different slopes of a mountain can determine the structure of ferns and lycophytes communities in a tropical forest of Brazil

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FELIPE C. NETTESHEIM

2014-03-01

Full Text Available A community of Ferns and Lycophytes was investigated by comparing the occurrence of species on different slopes of a paleoisland in Southeastern Brazil. Our goal was to evaluate the hypothesis that slopes with different geographic orientations determine a differentiation of Atlantic Forest ferns and lycophytes community. We recorded these plants at slopes turned towards the continent and at slopes turned towards the open sea. Analysis consisted of a preliminary assessment on fern beta diversity, a Non Metric Multidimensional Scaling (NMDS and a Student t-test to confirm if sites sampling units ordination was different at each axis. We further used the Pearson coefficient to relate fern species to the differentiation pattern and again Student's t-test to determine if richness, plant cover and abundance varied between the two sites. There was a relatively low number of shared species between the two sites and ferns and lycophytes community variation was confirmed. Some species were detected as indicators of the community variation but we were unable to detect richness, plant cover or abundance differences. Despite the evidence of this variation between the slopes, further works are needed to evaluate which processes are contributing to determine this pattern.

Fire intensity impacts on post-fire temperate coniferous forest net primary productivity

Science.gov (United States)

Sparks, Aaron M.; Kolden, Crystal A.; Smith, Alistair M. S.; Boschetti, Luigi; Johnson, Daniel M.; Cochrane, Mark A.

2018-02-01

Fire is a dynamic ecological process in forests and impacts the carbon (C) cycle through direct combustion emissions, tree mortality, and by impairing the ability of surviving trees to sequester carbon. While studies on young trees have demonstrated that fire intensity is a determinant of post-fire net primary productivity, wildland fires on landscape to regional scales have largely been assumed to either cause tree mortality, or conversely, cause no physiological impact, ignoring the impacted but surviving trees. Our objective was to understand how fire intensity affects post-fire net primary productivity in conifer-dominated forested ecosystems on the spatial scale of large wildland fires. We examined the relationships between fire radiative power (FRP), its temporal integral (fire radiative energy - FRE), and net primary productivity (NPP) using 16 years of data from the MOderate Resolution Imaging Spectrometer (MODIS) for 15 large fires in western United States coniferous forests. The greatest NPP post-fire loss occurred 1 year post-fire and ranged from -67 to -312 g C m-2 yr-1 (-13 to -54 %) across all fires. Forests dominated by fire-resistant species (species that typically survive low-intensity fires) experienced the lowest relative NPP reductions compared to forests with less resistant species. Post-fire NPP in forests that were dominated by fire-susceptible species were not as sensitive to FRP or FRE, indicating that NPP in these forests may be reduced to similar levels regardless of fire intensity. Conversely, post-fire NPP in forests dominated by fire-resistant and mixed species decreased with increasing FRP or FRE. In some cases, this dose-response relationship persisted for more than a decade post-fire, highlighting a legacy effect of fire intensity on post-fire C dynamics in these forests.

Water migration of macroelements in coniferous-broad-leaved forests of Sikhote-Alin

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N. K. Kozhevnikova

2017-06-01

Full Text Available In the paper, the natural water chemical composition spatial variability studies results in the mountain forest catchment are presented. It’s shown that the catchment biotic components’ impact upon water chemical composition is detected even at input as atmospheric precipitation. The input fluxes are acid, sulfate ones with high ratio of hydrogen, potassium and dissolved organic matter. Diversity of ecotopic conditions determines the further transformation of natural water chemical composition. The role of tree crowns in the transformation increases while the crown closure and stands’ age increase. According to macrocomponents transformation and rain acidity neutralization, forest associations form the sequence: mixed > coniferous > young deciduous ones. Dissolved organic carbon (DOC, potassium and calcium become the main components of water chemical composition, while sulfates dominate among anions. For vegetation period, 9–11 kg/ha of sulfates come below tree crown. Biogenic elements transport is gradually limited in soil profile at the migration stage. Sulfate-potassium composition throughfall in spruce-fir and secondary forests community transforms into sulfate-sodium-calcium. Hydrocarbonates predominate in soil water in broad-leaved-pine type of forest, and potassium output decreases 10 times. Geochemical type of river water keeps features of chemical composition of soil drained by river section. Negligible output of sulfates, hydrocarbonates and calcium from ecosystem is established for the headwaters. Negative balance of hydrocarbonates and calcium is compensated by significant input of these components with throughfall at catchments with predominantly pine-broad-leaved forest types.

Regression modeling and mapping of coniferous forest basal area and tree density from discrete-return lidar and multispectral data

Science.gov (United States)

Andrew T. Hudak; Nicholas L. Crookston; Jeffrey S. Evans; Michael K. Falkowski; Alistair M. S. Smith; Paul E. Gessler; Penelope Morgan

2006-01-01

We compared the utility of discrete-return light detection and ranging (lidar) data and multispectral satellite imagery, and their integration, for modeling and mapping basal area and tree density across two diverse coniferous forest landscapes in north-central Idaho. We applied multiple linear regression models subset from a suite of 26 predictor variables derived...

THE ROLE OF TREEFALL COMPLEXES IN REGENERATION OF TREE SPECIES AND IN MAINTAINING OF BIOLOGICAL DIVERSITY OF NATURAL BEECH AND DARK CONIFEROUS-BEECH FORESTS OF THE UKRAINIAN CARPATHIANS

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S. I. Ripa

2017-06-01

Full Text Available Understanding of maintaining biological diversity mechanisms is important for elaborating methods for the restoration of natural forests that most fully implement ecosystem functions. The objectives of work are: to identify intact beech and dark coniferous-beech forests of the Carpathians on the basis of analyzing history of nature management and field studies; to characterize the population structure of the main tree species in the intact forests of the Carpathians; to determine the renewal of various species of trees, shrubs, herbs and bryophytes to treefall microsites in the forest types studied. The objects of the research are monodominant beech forests and mixed (dark coniferous-beech forests of the Ukrainian Carpathians, in which beech (Fagus sylvatica, white fir (Abies alba and European spruce (Picea abies are the main dominant of tree sinusia. Monodominant beech forests (the age of stands 250–350 years were studied on 9 sample plots (from 1 to 1.05 ha laid in the Ugolsky forest range of the Carpathian Biosphere Reserve at an altitude of 600 to 1000 m above sea level, and also on the 2 sample plots (from 1 to 1.09 hectares laid in the Lower Volovets forestry at an altitude of 600–800 meters above sea level. Uneven-aged dark coniferous-beech forest (the age of forest stands is 250–300 years old was explored on one sample plot (1.2 ha laid in the Podlisnivsky forestry of the Carpathian National Park at an altitude of 750 m above sea level. Population analysis of the main tree and shrub species as well as geobotanical releves was made on the sample plots. Treefall microsite complexes were investigated to identify the peculiarities in the location of tree undergrowth, herb and moss species in beech and mixed forests. The following elements of treefall microsite complex were singled out: treefall pit, treefall mound and tree trunk. At each treefall microsite complex the research was carried out according to the following scheme: an

Draft genome sequence of Burkholderia sordidicola S170, a potential plant growth promoter isolated from coniferous forest soil in the Czech Republic

DEFF Research Database (Denmark)

Lladó, Salvador; Xu, Zhuofei; Sørensen, Søren Johannes

2014-01-01

Burkholderia species are key players in the accumulation of carbon from cellulose decomposition in coniferous forest ecosystems. We report here the draft genome of Burkholderia sordidicola strain S170, containing features associated with known genes involved in plant growth promotion...

Methane oxidation in soil profiles of Dutch and Finnish coniferous forests with different soil texture and atmospheric nitrogen deposition

NARCIS (Netherlands)

Saari, A.; Martikainen, P.J.; Ferm, A.; Ruuskanen, J.; De Boer, W.; Troelstra, S.R.; Laanbroek, H.J.

1997-01-01

We studied methane oxidation capacity in soil profiles of Dutch and Finnish coniferous forests. The Finnish sites (n = 9) had nitrogen depositions from 3 to 36 kg N ha(-1) a(-1). The deposition of N on the Dutch sites (n = 13) was higher ranging from 50 to 92 kg N ha(-1) a(-1). The Dutch sites had

Methane oxidation in soil profiles of Dutch and Finnish coniferous forests with different soil texture and atmospheric nitrogen deposition

NARCIS (Netherlands)

Saari, A.; Martikainen, P.J.; Ferm, A.; Ruuskanen, J.; Boer, W. de; Troelstra, S.R.; Laanbroek, H.J.

1997-01-01

We studied methane oxidation capacity in soil profiles of Dutch and Finnish coniferous forests. The Finnish sites (n = 9) had nitrogen depositions from 3 to 36 kg N ha⁻¹ a⁻¹. The deposition of N on the Dutch sites (n = 13) was higher ranging from 50 to 92 kg N ha⁻¹ a⁻¹. The Dutch sites had also

Belowground ectomycorrhizal fungal communities respond to liming in three southern Swedish coniferous forest stands

DEFF Research Database (Denmark)

Kjøller, Rasmus; Clemmensen, Karina

2009-01-01

In this study we report on changes in the belowground ectomycorrhizal fungal communities in southern Swedish coniferous forests as a consequence of liming with 3-7 ton limestone per hectare 16 years prior to the study. A total of 107 ectomycorrhizal fungi were identified from 969 independently...... sampled root tips by sequencing the internal transcribed spacer region of the ribosomal DNA. Forty, 59 and 51 species were identified in three pine and spruce forests. Within all sites only about 25% of the species overlapped between the limed and the reference areas. However, the most abundant species...... were often found in both limed and reference plots and 60-70% of the root tips at each site were colonised by species occurring in both limed and reference plots. Across all three sites, fungal species belonging to the genus Tylospora and the order Pezizales became significantly more frequent in limed...

Altitudinal variation in soil organic carbon stock in coniferous subtropical and broadleaf temperate forests in Garhwal Himalaya

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Kumar Munesh

2009-08-01

Full Text Available Abstract Background The Himalayan zones, with dense forest vegetation, cover a fifth part of India and store a third part of the country reserves of soil organic carbon (SOC. However, the details of altitudinal distribution of these carbon stocks, which are vulnerable to forest management and climate change impacts, are not well known. Results This article reports the results of measuring the stocks of SOC along altitudinal gradients. The study was carried out in the coniferous subtropical and broadleaf temperate forests of Garhwal Himalaya. The stocks of SOC were found to be decreasing with altitude: from 185.6 to 160.8 t C ha-1 and from 141.6 to 124.8 t C ha-1 in temperature (Quercus leucotrichophora and subtropical (Pinus roxburghii forests, respectively. Conclusion The results of this study lead to conclusion that the ability of soil to stabilize soil organic matter depends negatively on altitude and call for comprehensive theoretical explanation

Temporal and spatial variation of nitrogen transformations in a coniferous soil.

NARCIS (Netherlands)

Laverman, A.M.; Zoomer, H.R.; van Verseveld, H.W.; Verhoef, H.A.

2000-01-01

Forest soils show a great degree of temporal and spatial variation of nitrogen mineralization. The aim of the present study was to explain temporal variation in nitrate leaching from a nitrogen-saturated coniferous forest soil by potential nitrification, mineralization rates and nitrate uptake by

Fungal mycelium and decomposition of needle litter in three contrasting coniferous forests

Science.gov (United States)

Virzo De Santo, Amalia; Rutigliano, Flora Angela; Berg, Björn; Fioretto, Antonietta; Puppi, Gigliola; Alfani, Anna

2002-08-01

The fungal mycelium ingrowth and the rates of mass loss and respiration of needle litter of Pinus pinea, Pinus laricio, Pinus sylvestris, and Abies alba were investigated, in three coniferous forests, over a 3-year period by means of a composite set of incubations. In the early stages, the fungal flora of the decomposing needles was dominated by dematiaceous hyphomycetes and coelomycetes. Basidiomycetes reached a peak after 6 months on pine needles, but were absent from the N-rich needles of A. alba. Soil fungi ( Penicillium, Trichoderma, Absidia, Mucor sp. pl.) became most frequent in later stages. At the end of the study period, the total mycelium amount showed the lowest values in all pine needles incubated in the P. laricio forest and the highest ones in P. pinea needles incubated in the P. pinea forest. In all data sets, as in data for boreal forests examined for comparison, the concentration of litter fungal mycelium versus litter mass loss followed a common exponential model. However, in later stages, the amount of litter fungal mycelium was very close to that of the humus at the incubation site, thus supporting the hypothesis of a logistic growth pattern. Respiration rates of decomposing litters varied with season and decreased with litter age to values close to those of the humus at the incubation site. Respiration of water-saturated litter was negatively correlated with the total mycelium concentration, and this was consistent with the observation that in far-decomposed litter only a minor fraction of the total mycelium is alive.

Distribution and dynamics of the invasive native hay-scented fern

Science.gov (United States)

Songlin Fei; Peter Gould; Melanie Kaeser; Kim. Steiner

2010-01-01

The spread and dominance of the invasive native hay-scented fern in the understory is one of the most significant changes to affect the forest ecosystems in the northeastern United States in the last century. We studied changes in the distribution and dynamics of hay-scented fern at a large scale over a 10-yr period in Pennsylvania. The study included 56 stands...

The Influence of DEM Quality on Mapping Accuracy of Coniferous- and Deciduous-Dominated Forest Using TerraSAR‑X Images

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Gerald Kändler

2012-03-01

Full Text Available Climate change is a factor that largely contributes to the increase of forest areas affected by natural damages. Therefore, the development of methodologies for forest monitoring and rapid assessment of affected areas is required. Space-borne synthetic aperture radar (SAR imagery with high resolution is now available for large-scale forest mapping and forest monitoring applications. However, a correct interpretation of SAR images requires an adequate preprocessing of the data consisting of orthorectification and radiometric calibration. The resolution and quality of the digital elevation model (DEM used as reference is crucial for this purpose. Therefore, the primary aim of this study was to analyze the influence of the DEM quality used in the preprocessing of the SAR data on the mapping accuracy of forest types. In order to examine TerraSAR-X images to map forest dominated by deciduous and coniferous trees, High Resolution SpotLight images were acquired for two study sites in southern Germany. The SAR images were preprocessed with a Shuttle Radar Topography Mission (SRTM DEM (resolution approximately 90 m, an airborne laser scanning (ALS digital terrain model (DTM (5 m resolution, and an ALS digital surface model (DSM (5 m resolution. The orthorectification of the SAR images using high resolution ALS DEMs was found to be important for the reduction of errors in pixel location and to increase the classification accuracy of forest types. SAR images preprocessed with ALS DTMs resulted in the highest classification accuracies, with kappa coefficients of 0.49 and 0.41, respectively. SAR images preprocessed with ALS DTMs resulted in greater accuracy than those preprocessed with ALS DSMs in most cases. The classification accuracy of forest types using SAR images preprocessed with the SRTM DEM was fair, with kappa coefficients of 0.23 and 0.32, respectively.Analysis of the radar backscatter indicated that sample plots dominated by coniferous trees

Effects of ground fires on element dynamics in mountainous coniferous forest in Germany

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Kerstin Näthe

2012-09-01

Full Text Available Disturbances such as fires are a natural phenomenon of forested ecosystems, having a different impact on (micro- climate (e.g. emissions of gases and aerosols, ecology (destruction of flora and fauna and nutrient cycles especially in the soils. Forest fires alter the spatial distribution (forest floor vs. mineral soil, binding forms (organic vs. inorganic and availability (water solubility of organic substances and nutrients. The effects of fires on chemical, biological and physical soil properties in forested ecosystems have been intensively studied in the last decades, especially in the Mediterranean area and North America. However, differences in fire intensity, forest type (species, age and location (climate, geological substrate, nutrient status lead to divergent results. Furthermore, only a few case studies focused on the effects of ground fires in hilly landscapes, on the vertical and lateral water-driven fluxes of elements (C, N, nutrients, as well as on the input of fire-released terrestrial nutrients into aquatic ecosystems. Thus, this study will evaluate the effects of low-severity fires on nutrient cycling in a coniferous forest in a hilly landscape connected to an aquatic system. At three spatially independent sites three paired plots (control and manipulated were chosen at a forested site in Thuringia, Germany. All plots are similar in the vegetation cover and pedogenetic properties.In relation to control sites, this study will examine the effects of low-severity fires on:a the mobilization of organic carbon and nutrients (released from ash material and the forest floor via leachate and erosion paths,b the binding form (inorganic/organic of elements and organic compounds, and c the particle size fraction (DOM/POM of elements and organic compounds.The goal of this study is a better understanding of the impact of forest fires on element cycling and release in a hilly landscape connected to an aquatic system, supposedly driven by

Spatial Characteristics of Edible Wild Fern Harvesting in Mountainous Villages in Northeastern Japan Using GPS Tracks

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Toshiya Matsuura

2014-02-01

Full Text Available Wild plants in forests provide valuable living resources for rural communities. The location where local people harvest various species is important to the wise use of forest ecosystem services. Using global positioning system (GPS tracking of harvesters’ activities as well as geographic information system (GIS and a generalized linear model (GLM, this study analyzed the spatial differences among harvesting sites of three popular edible ferns, i.e., ostrich fern (Matteuccia struthiopteris, bracken (Pteridium aquilinum, and royal fern (Osmunda japonica, in mountainous villages of Northeastern Japan. The explanatory variables used were vegetation classes, terrain features, and proximity to roadways. The GLM yielded clear differences in harvesting sites among species that were affected by both the species’ ecological characteristics and human behavior. Ostrich fern was harvested mainly in canopy openings along valley floors, whereas royal fern harvest sites were frequently located in snow avalanche scrublands. Bracken was mainly harvested in deforested areas or young conifer plantations. Whereas ostrich fern and bracken harvest sites were restricted by the accessibility from roadways, this was not the case for royal fern. Potential harvest sites of ferns were estimated with the highest value for bracken. Our results suggest that local harvesters seriously consider various natural and anthropogenic factors to maintain effective and sustainable harvesting.

Migration and bioavailability of 137Cs in forest soil of southern Germany

International Nuclear Information System (INIS)

Konopleva, I.; Klemt, E.; Konoplev, A.; Zibold, G.

2009-01-01

To give a quantitative description of the radiocaesium soil-plant transfer for fern (Dryopteris carthusiana) and blackberry (Rubus fruticosus), physical and chemical properties of soils in spruce and mixed forest stands were investigated. Of special interest was the selective sorption of radiocaesium, which was determined by measuring the Radiocaesium Interception Potential (RIP). Forest soil and plants were taken at 10 locations of the Altdorfer Wald (5 sites in spruce forest and 5 sites in mixed forest). It was found that the bioavailability of radiocaesium in spruce forest was on average seven times higher than in mixed forest. It was shown that important factors determining the bioavailability of radiocaesium in forest soil were its exchangeability and the radiocaesium interception potential (RIP) of the soil. Low potassium concentration in soil solution of forest soils favors radiocaesium soil-plant transfer. Ammonium in forest soils plays an even more important role than potassium as a mobilizer of radiocaesium. The availability factor - a function of RIP, exchangeability and cationic composition of soil solution - characterized reliably the soil-plant transfer in both spruce and mixed forest. For highly organic soils in coniferous forest, radiocaesium sorption at regular exchange sites should be taken into account when its bioavailability is considered

Knowledge-Based Estimation of Edible Fern Harvesting Sites in Mountainous Communities of Northeastern Japan

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Toshiya Matsuura

2013-12-01

Full Text Available Once local expert knowledge regarding the harvesting of various non-timber forest products (NTFPs is lost, it is difficult to recover. We investigated whether the knowledge of expert forest harvesters can be used to determine the habitat distribution and harvesting sites of three popular edible wild ferns, i.e., ostrich fern (Matteuccia struthiopteris, bracken (Pteridium aquilinum, and royal fern (Osmunda japonica, in mountainous communities of western Fukushima, Japan. Using multi-criteria evaluation (MCE based on the analytic hierarchy process (AHP and geographic information system (GIS, we found that harvesters were easily able to recognize differences in the spatial characteristics of the habitat distribution of fern species due to both natural and anthropogenic factors. These factors were described by various GIS layers, such as vegetation and terrain features (e.g., gradient, aspect, and slope position derived from a 20-m digital elevation model (DEM. Harvesting sites were limited by their distance from a roadway, which differed among species. By comparison with the GPS records of actual harvesting sites, we estimated the potential harvesting sites of each fern species with reasonable accuracy, particularly for bracken. Our results show that the knowledge of expert forest harvesters can be quantified using MCE and GIS, which is useful for determining the spatial characteristics of NTFP harvesting and ensuring sustainable management practices.

Comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry in the identification of organic compounds in atmospheric aerosols from coniferous forest

NARCIS (Netherlands)

Kallio, M.; Jussila, M.; Rissanen, T.; Anttila, P.; Hartonen, K.; Reissell, A.; Vreuls, R.J.J.; Adahchour, M.; Hyotylainen, T.

2006-01-01

Comprehensive two-dimensional gas chromatography coupled to time-of-flight mass spectrometry (GC × GC-TOF-MS) was applied in the identification of organic compounds in atmospheric aerosols from coniferous forest. The samples were collected at Hyytiälä, Finland, as part of the QUEST campaign, in

Migration and bioavailability of {sup 137}Cs in forest soil of southern Germany

Energy Technology Data Exchange (ETDEWEB)

Konopleva, I.; Klemt, E. [Hochschule Ravensburg-Weingarten, University of Applied Sciences, 88250 Weingarten (Germany); Konoplev, A. [Scientific Production Association ' TYPHOON' , Obninsk (Russian Federation); Zibold, G. [Hochschule Ravensburg-Weingarten, University of Applied Sciences, 88250 Weingarten (Germany)], E-mail: zibold@hs-weingarten.de

2009-04-15

To give a quantitative description of the radiocaesium soil-plant transfer for fern (Dryopteris carthusiana) and blackberry (Rubus fruticosus), physical and chemical properties of soils in spruce and mixed forest stands were investigated. Of special interest was the selective sorption of radiocaesium, which was determined by measuring the Radiocaesium Interception Potential (RIP). Forest soil and plants were taken at 10 locations of the Altdorfer Wald (5 sites in spruce forest and 5 sites in mixed forest). It was found that the bioavailability of radiocaesium in spruce forest was on average seven times higher than in mixed forest. It was shown that important factors determining the bioavailability of radiocaesium in forest soil were its exchangeability and the radiocaesium interception potential (RIP) of the soil. Low potassium concentration in soil solution of forest soils favors radiocaesium soil-plant transfer. Ammonium in forest soils plays an even more important role than potassium as a mobilizer of radiocaesium. The availability factor - a function of RIP, exchangeability and cationic composition of soil solution - characterized reliably the soil-plant transfer in both spruce and mixed forest. For highly organic soils in coniferous forest, radiocaesium sorption at regular exchange sites should be taken into account when its bioavailability is considered.

Allometric biomass equations for 12 tree species in coniferous and broadleaved mixed forests, Northeastern China.

Science.gov (United States)

He, Huaijiang; Zhang, Chunyu; Zhao, Xiuhai; Fousseni, Folega; Wang, Jinsong; Dai, Haijun; Yang, Song; Zuo, Qiang

2018-01-01

Understanding forest carbon budget and dynamics for sustainable resource management and ecosystem functions requires quantification of above- and below-ground biomass at individual tree species and stand levels. In this study, a total of 122 trees (9-12 per species) were destructively sampled to determine above- and below-ground biomass of 12 tree species (Acer mandshuricum, Acer mono, Betula platyphylla, Carpinus cordata, Fraxinus mandshurica, Juglans mandshurica, Maackia amurensis, P. koraiensis, Populus ussuriensis, Quercus mongolica, Tilia amurensis and Ulmus japonica) in coniferous and broadleaved mixed forests of Northeastern China, an area of the largest natural forest in the country. Biomass allocation was examined and biomass models were developed using diameter as independent variable for individual tree species and all species combined. The results showed that the largest biomass allocation of all species combined was on stems (57.1%), followed by coarse root (21.3%), branch (18.7%), and foliage (2.9%). The log-transformed model was statistically significant for all biomass components, although predicting power was higher for species-specific models than for all species combined, general biomass models, and higher for stems, roots, above-ground biomass, and total tree biomass than for branch and foliage biomass. These findings supplement the previous studies on this forest type by additional sample trees, species and locations, and support biomass research on forest carbon budget and dynamics by management activities such as thinning and harvesting in the northeastern part of China.

The Roll of Canopy on Interception and Redistribution of Anthropogenic Radionuclides Derived from Fukushima Daiichi Nuclear Power Plant Accident in Coniferous Forest Plantations

Science.gov (United States)

Kato, H.; Onda, Y.; Kawaguchi, S.; Gomi, T.

2011-12-01

Soil, vegetation and other ecological compartments are expected to be highly contaminated by the deposited radionuclides after the Fukushima Daiichi nuclear power plant (NPP) accident triggered by a magnitude 9.1 earthquake and the resulting tsunami on Marchi 11, 2011. A large proportion of radionuclides which deposited on forest area are trapped by canopies, throughfall and stemflow are the most important pathways for the input of radionuclides into the soil of forest floor. In this study, to investigate the roll of forest canopy on interception and redistribution of the deposited radionuclides, a series of field monitoring experiment of throughfall and stemflow were conducted in coniferous forest plantations in Tochigi prefecture, 170 km southwest from the NPP. A set of 20 throughfall collectors with latticelike distribution and 5 stemflow collectors were located in the 10m × 10m interception plot, and the activities of caesium (137Cs, 134Cs) and radioiodine (131I) in throughfall and stemflow were quantified by using a high purity n-type germanium coaxial gamma ray detectors. Rainfall, throughfall, and stemflow samples were collected from 10 rainfall events, which includes first rainfall event after the NPP accident. The cumulative fallout of radionuclides in the study site was 3400 Bq m-2 for 137Cs, 3300 Bq m-2 for 134Cs, and 26000 Bq m-2 for 131I, respectively. The 137Cs in rainfall decreased exponentially with time since the NPP accident. For the rainfall event of 28 March, which is first rainfall event after the NPP accident, both the amount and concentration of caesium clearly increased with throughfall, whereas the concentration of radioiodine decreased with throughfall. For the subsequent rainfall events, the concentration of caesium decreased with throughfall, whereas radioiodine was not detected as a result of decay due to short half-life. At the end of May, approximately 30% and 60% of total caesium deposited after the NPP accident remained on the

Variation of functional clonal traits along elevation in two fern species

International Nuclear Information System (INIS)

Song, Y.B.; Chen, L.Y.; Xiong, W.

2015-01-01

Phenotypical plasticity is generally considered among adaptive strategies by which plants can cope with environmental variation in space and time. Although much is known about plasticity in seed plants in terms of functional clonal traits while little is known about ferns. Variation of functional clonal traits of two ferns Dicranopteris dichotoma and Diplopterygium glaucum among plots differing in elevation in a subtropical evergreen broad-leaved forest in southern China was investigated. Along with elevation increasing the two fern species showed similar variation pattern of functional clonal traits: stable spacer length, increasing specific spacer length and decreasing spacer weight per ramet and specific spacer weight. The two ferns species had similar variation pattern of ramet performance traits but different variation pattern of ramet population properties. These results suggest an evolutionary trade-off between functions of foraging for and storing of resources in the two ferns, with a functional preference for the foraging in response to environmental change. (author)

Adaptive genetic potential of coniferous forest tree species under climate change: implications for sustainable forest management

Science.gov (United States)

Mihai, Georgeta; Birsan, Marius-Victor; Teodosiu, Maria; Dumitrescu, Alexandru; Daia, Mihai; Mirancea, Ionel; Ivanov, Paula; Alin, Alexandru

2017-04-01

coniferous species for a sustainable forest management in the context of climate change), financed by the Executive Agency for Higher Education, Research, Development and Innovation Funding, grant number PN-II-PC-PCCA-2013-4-0695.

Plantation-Seeding Forest Plantations – the New Method for Regeneration of Coniferous Forests at Large Clearings on Burned Lands

Directory of Open Access Journals (Sweden)

V. V. Tarakanov

2014-02-01

Full Text Available The new method of restoration of coniferous stands on large felling areas on burnt lands that lack seed trees is discussed. It involves limited planting of big grafted seedlings of quality wood, that have a high level of seed production, with the purpose of the subsequent natural sowing on these territories. Results of two-year-old research on approbation of the method on cuttings on large felling areas on burnt lands in conditions of the mid-Ob' river pine forests are stated. A good viability of «seed cultures» is noted. There is damage of the grafting pines by elk. Therefore there is a problem of protecting plantations against elk. For preservation of a high level of genetic variability of pine stands it is desirable to use in «seed cultures» the best trees from local plantings.

Carbon stocks of three secondary coniferous forests along an altitudinal gradient on Loess Plateau in inland China

Science.gov (United States)

Liu, Ning; Nan, Hongwei

2018-01-01

Natural forests in inland China are generally distributed in montane area and secondary due to a semi-arid climate and past anthropogenic disturbances. However, quantification of carbon (C) stock in these forests and the role of altitude in determining C storage and its partition among ecosystem components are unclear. We sampled 54 stands of three secondary coniferous forests (Larix principis-rupprechtii (LP) forest, Picea meyerii (PM) forest and Pinus tabulaeformis (PT) forest) on Loess Plateau in an altitudinal range of 1200-2700m a.s.l. C stocks of tree layer, shrub layer, herb layer, coarse wood debris, forest floor and soil were estimated. We found these forests had relatively high total C stocks. Driven by both higher vegetation and soil C stocks, total C stocks of LP and PM forests in the high altitudinal range were 375.0 and 368.4 t C ha-1 respectively, significantly higher than that of PT forest in the low altitudinal range (230.2 t C ha-1). In addition, understory shrubs accounted for about 20% of total biomass in PT forest. The proportions of vegetation to total C stock were similar among in the three forests (below 45%), so were the proportions of soil C stock (over 54%). Necromass C stocks were also similar among these forests, but their proportions to total C stock were significantly lower in LP and PM forests (1.4% and 1.6%) than in PT forest (3.0%). Across forest types, vegetation biomass and soil C stock simultaneously increased with increasing altitude, causing fairly unchanged C partitioning among ecosystem components along the altitudinal gradient. Soil C stock also increased with altitude in LP and PT forests. Forest floor necromass decreased with increasing altitude across the three forests. Our results suggest the important role of the altitudinal gradient in C sequestration and floor necromass of these three forests in terms of alleviated water conditions and in soil C storage of LP and PM forests in terms of temperature change. PMID

Analyis on the vascular epiphytes of tree ferns in a montane rain forest in Costa Rica

OpenAIRE

Jens Bittner; Javier Trejos Zelaya

2009-01-01

The relationships between epiphytes and host specifity are known. We investigated the relation between specific epiphytes and tree fern trunks. Only some epiphytes are frequent or very frequent on tree ferns. Most of the epiphyte species are unspecific on these trunks. Blechnum fragile are the only found exclusively on tree ferns. We also observed different epiphyte communities dependent on the tree fern species and the morphology of the tree trunk.

Influence of Forest-Canopy Morphology and Relief on Spectral Characteristics of Taiga Forests

Science.gov (United States)

Zhirin, V. M.; Knyazeva, S. V.; Eydlina, S. P.

2017-12-01

The article deals with the results of a statistical analysis reflecting tendencies (trends) of the relationship between spectral characteristics of taiga forests, indicators of the morphological structure of forest canopy and illumination of the territory. The study was carried out on the example of the model forest territory of the Priangarskiy taiga region of Eastern Siberia (Krasnoyarsk krai) using historical data (forest inventory 1992, Landsat 5 TM 16.06.1989) and the digital elevation model. This article describes a method for determining the quantitative indicator of morphological structure of forest canopy based on taxation data, and the authors propose to subdivide the morphological structure into high complexity, medium complexity, and relatively simple. As a result of the research, dependences of average values of spectral brightness in near and short-wave infrared channels of a Landsat 5 TM image for dark-coniferous, light-coniferous and deciduous forests from the degree of complexity of the forest-canopy structure are received. A high level of variance and maximum brightness average values are marked in green moss (hilocominosa) dark-coniferous and various-grass (larioherbosa) dark-coniferous forests and light-coniferous forests with a complex structure of canopy. The parvifoliate forests are characterized by high values of brightness in stands with a relatively simple structure of the canopy and by a small variance in brightness of any degree of the structure of the canopy complexity. The increase in brightness for the lit slopes in comparison with shaded ones in all stands with a difficult morphological canopy structure is revealed. However, the brightness values of the lit and shaded slopes do not differ for stands with a medium complexity of the structure. It is noted that, in addition to the indicator of the forest-canopy structure, the possible impact on increasing the variance of spectral brightness for the taxation plot has a variability of the

Analyis on the vascular epiphytes of tree ferns in a montane rain forest in Costa Rica

Directory of Open Access Journals (Sweden)

Jens Bittner

2009-02-01

Full Text Available The relationships between epiphytes and host specifity are known. We investigated the relation between specific epiphytes and tree fern trunks. Only some epiphytes are frequent or very frequent on tree ferns. Most of the epiphyte species are unspecific on these trunks. Blechnum fragile are the only found exclusively on tree ferns. We also observed different epiphyte communities dependent on the tree fern species and the morphology of the tree trunk.

Woody biomass production lags stem-girth increase by over one month in coniferous forests.

Science.gov (United States)

Cuny, Henri E; Rathgeber, Cyrille B K; Frank, David; Fonti, Patrick; Mäkinen, Harri; Prislan, Peter; Rossi, Sergio; Del Castillo, Edurne Martinez; Campelo, Filipe; Vavrčík, Hanuš; Camarero, Jesus Julio; Bryukhanova, Marina V; Jyske, Tuula; Gričar, Jožica; Gryc, Vladimír; De Luis, Martin; Vieira, Joana; Čufar, Katarina; Kirdyanov, Alexander V; Oberhuber, Walter; Treml, Vaclav; Huang, Jian-Guo; Li, Xiaoxia; Swidrak, Irene; Deslauriers, Annie; Liang, Eryuan; Nöjd, Pekka; Gruber, Andreas; Nabais, Cristina; Morin, Hubert; Krause, Cornelia; King, Gregory; Fournier, Meriem

2015-10-26

Wood is the main terrestrial biotic reservoir for long-term carbon sequestration(1), and its formation in trees consumes around 15% of anthropogenic carbon dioxide emissions each year(2). However, the seasonal dynamics of woody biomass production cannot be quantified from eddy covariance or satellite observations. As such, our understanding of this key carbon cycle component, and its sensitivity to climate, remains limited. Here, we present high-resolution cellular based measurements of wood formation dynamics in three coniferous forest sites in northeastern France, performed over a period of 3 years. We show that stem woody biomass production lags behind stem-girth increase by over 1 month. We also analyse more general phenological observations of xylem tissue formation in Northern Hemisphere forests and find similar time lags in boreal, temperate, subalpine and Mediterranean forests. These time lags question the extension of the equivalence between stem size increase and woody biomass production to intra-annual time scales(3, 4, 5, 6). They also suggest that these two growth processes exhibit differential sensitivities to local environmental conditions. Indeed, in the well-watered French sites the seasonal dynamics of stem-girth increase matched the photoperiod cycle, whereas those of woody biomass production closely followed the seasonal course of temperature. We suggest that forecasted changes in the annual cycle of climatic factors(7) may shift the phase timing of stem size increase and woody biomass production in the future.

Between Two Fern Genomes

Science.gov (United States)

2014-01-01

Ferns are the only major lineage of vascular plants not represented by a sequenced nuclear genome. This lack of genome sequence information significantly impedes our ability to understand and reconstruct genome evolution not only in ferns, but across all land plants. Azolla and Ceratopteris are ideal and complementary candidates to be the first ferns to have their nuclear genomes sequenced. They differ dramatically in genome size, life history, and habit, and thus represent the immense diversity of extant ferns. Together, this pair of genomes will facilitate myriad large-scale comparative analyses across ferns and all land plants. Here we review the unique biological characteristics of ferns and describe a number of outstanding questions in plant biology that will benefit from the addition of ferns to the set of taxa with sequenced nuclear genomes. We explain why the fern clade is pivotal for understanding genome evolution across land plants, and we provide a rationale for how knowledge of fern genomes will enable progress in research beyond the ferns themselves. PMID:25324969

Modeling the early-phase redistribution of radiocesium fallouts in an evergreen coniferous forest after Chernobyl and Fukushima accidents

Energy Technology Data Exchange (ETDEWEB)

Calmon, P.; Gonze, M.-A.; Mourlon, Ch.

2015-10-01

Following the Chernobyl accident, the scientific community gained numerous data on the transfer of radiocesium in European forest ecosystems, including information regarding the short-term redistribution of atmospheric fallout onto forest canopies. In the course of international programs, the French Institute for Radiological Protection and Nuclear Safety (IRSN) developed a forest model, named TREE4 (Transfer of Radionuclides and External Exposure in FORest systems), 15 years ago. Recently published papers on a Japanese evergreen coniferous forest contaminated by Fukushima radiocesium fallout provide interesting and quantitative data on radioactive mass fluxes measured within the forest in the months following the accident. The present study determined whether the approach adopted in the TREE4 model provides satisfactory results for Japanese forests or whether it requires adjustments. This study focused on the interception of airborne radiocesium by forest canopy, and the subsequent transfer to the forest floor through processes such as litterfall, throughfall, and stemflow, in the months following the accident. We demonstrated that TREE4 quite satisfactorily predicted the interception fraction (20%) and the canopy-to-soil transfer (70% of the total deposit in 5 months) in the Tochigi forest. This dynamics was similar to that observed in the Höglwald spruce forest. However, the unexpectedly high contribution of litterfall (31% in 5 months) in the Tochigi forest could not be reproduced in our simulations (2.5%). Possible reasons for this discrepancy are discussed; and sensitivity of the results to uncertainty in deposition conditions was analyzed. - Highlights: • Transfer of radiocesium atmospheric fallout in evergreen forests was modeled. • The model was tested using observations from Chernobyl and Fukushima accidents. • Model predictions of canopy interception and depuration agree with measurements. • Unexpectedly high contribution of litterfall for the

Using field data to assess model predictions of surface and ground fuel consumption by wildfire in coniferous forests of California

Science.gov (United States)

Lydersen, Jamie M.; Collins, Brandon M.; Ewell, Carol M.; Reiner, Alicia L.; Fites, Jo Ann; Dow, Christopher B.; Gonzalez, Patrick; Saah, David S.; Battles, John J.

2014-03-01

Inventories of greenhouse gas (GHG) emissions from wildfire provide essential information to the state of California, USA, and other governments that have enacted emission reductions. Wildfires can release a substantial amount of GHGs and other compounds to the atmosphere, so recent increases in fire activity may be increasing GHG emissions. Quantifying wildfire emissions however can be difficult due to inherent variability in fuel loads and consumption and a lack of field data of fuel consumption by wildfire. We compare a unique set of fuel data collected immediately before and after six wildfires in coniferous forests of California to fuel consumption predictions of the first-order fire effects model (FOFEM), based on two different available fuel characterizations. We found strong regional differences in the performance of different fuel characterizations, with FOFEM overestimating the fuel consumption to a greater extent in the Klamath Mountains than in the Sierra Nevada. Inaccurate fuel load inputs caused the largest differences between predicted and observed fuel consumption. Fuel classifications tended to overestimate duff load and underestimate litter load, leading to differences in predicted emissions for some pollutants. When considering total ground and surface fuels, modeled consumption was fairly accurate on average, although the range of error in estimates of plot level consumption was very large. These results highlight the importance of fuel load input to the accuracy of modeled fuel consumption and GHG emissions from wildfires in coniferous forests.

Incubation of air-pollution-control residues from secondary Pb smelter in deciduous and coniferous organic soil horizons: Leachability of lead, cadmium and zinc

Energy Technology Data Exchange (ETDEWEB)

Chrastny, Vladislav, E-mail: vladislavchrastny@seznam.cz [University of South Bohemia, Faculty of Science, Studentska 13, 370 05 Ceske Budejovice (Czech Republic); Czech University of Life Sciences Prague, Faculty of Environmental Sciences, Kamycka 129, 165 21 Prague 6 (Czech Republic); Vanek, Ales [Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Kamycka 129, 165 21 Praha 6 (Czech Republic); Komarek, Michael [Czech University of Life Sciences Prague, Faculty of Environmental Sciences, Kamycka 129, 165 21 Prague 6 (Czech Republic); Farkas, Juraj [Czech Geological Survey, Geologicka 6, 152 00 Praha 5 (Czech Republic); Drabek, Ondrej; Vokurkova, Petra [Czech University of Life Sciences Prague, Faculty of Agrobiology, Food and Natural Resources, Kamycka 129, 165 21 Praha 6 (Czech Republic); Nemcova, Jana [University of South Bohemia, Faculty of Agriculture, Studentska 13, 370 05 Ceske Budejovice (Czech Republic)

2012-03-30

Highlights: Black-Right-Pointing-Pointer Pb smelter fly ash was incubated in forest soil horizons to assess metal mobility. Black-Right-Pointing-Pointer The metal mobilization depends on pH and the ratio of humic/fulvic acids to SOM. Black-Right-Pointing-Pointer The lowest mobilization of Pb, Zn and Cd took place in horizon H (coniferous forest). Black-Right-Pointing-Pointer A huge amount of Cd was found to have leached in the horizon F (deciduous forest). Black-Right-Pointing-Pointer More vulnerable to metal leaching from APC residues is soil from deciduous forest. - Abstract: The leachability of air-pollution-control (APC) residues from a secondary lead smelter in organic soil horizons (F and H) from a deciduous and a coniferous forest during incubation periods of 0, 3 and 6 months were compared in this work. While the concentration of Pb, Zn and Cd associated with the exchangeable/acid extractable fraction in the horizon F from the coniferous forest was higher compared to the deciduous, significantly lower concentrations in the humified horizon H was found. It is suggested that lower pH and a higher share of fulvic acids fraction (FAs) of solid phase soil organic matter (SOM) in the humified soil horizon H from the coniferous compared to the deciduous forest is responsible for a higher metal association with solid phase SOM and therefore a lower metal leaching in a soil system. From this point of view, the humified soil horizon H from the deciduous forest represents a soil system more vulnerable to Pb, Zn and Cd leaching from APC residues.

The effect of nitrogen additions on bracken fern and its insect herbivores at sites with high and low atmospheric pollution

Science.gov (United States)

M.E. Jones; M.E. Fenn; T.D. Paine

2011-01-01

The impact of atmospheric pollution, including nitrogen deposition, on bracken fern herbivores has never been studied. Bracken fern is globally distributed and has a high potential to accumulate nitrogen in plant tissue. We examined the response of bracken fern and its herbivores to N fertilization at a high and low pollution site in forests downwind of Los Angeles,...

The genetic structure of the mountain forest butterfly Erebia euryale unravels the late Pleistocene and postglacial history of the mountain coniferous forest biome in Europe.

Science.gov (United States)

Schmitt, Thomas; Haubrich, Karola

2008-05-01

The distribution of the mountain coniferous forest biome in Europe throughout time is not sufficiently understood. One character species of this habitat type is the large ringlet, Erebia euryale well reflecting the extension of this biome today, and the genetic differentiation of this species among and within mountain systems may unravel the late Pleistocene history of this habitat type. We therefore analysed the allozyme pattern of 381 E. euryale individuals from 11 populations in four different European mountain systems (Pyrenees, Alps, Carpathians, Rila). All loci analysed were polymorphic. The mean F(ST) over all samples was high (20%). Furthermore, the mean genetic distance among samples was quite high (0.049). We found four different groups well supported by cluster analyses, bootstraps and hierarchical variance analyses: Pyrenees, western Alps, eastern Alps and southeastern Europe (Carpathians and Rila). The genetic diversity of the populations was highest in the southeastern European group and stepwise decreased westwards. Interestingly, the populations from Bulgaria and Romania were almost identical; therefore, we assume that they were not separated by the Danube Valley, at least during the last ice age. On the contrary, the differentiation among the three western Alps populations was considerable. For all these reasons, we assume that (i) the most important refugial area for the coniferous mountain forest biome in Europe has been located in southeastern Europe including at least parts of the Carpathians and the Bulgarian mountains; (ii) important refugial areas for this biome existed at the southeastern edge of the Alps; (iii) fragments of this habitat types survived along the southwestern Alps, but in a more scattered distribution; and (iv) relatively small relicts have persisted somewhere at the foothills of the Pyrenees.

Substantial secondary organic aerosol formation in a coniferous forest: observations of both day- and nighttime chemistry

Directory of Open Access Journals (Sweden)

A. K. Y. Lee

2016-06-01

Full Text Available Substantial biogenic secondary organic aerosol (BSOA formation was investigated in a coniferous forest mountain region in Whistler, British Columbia. A largely biogenic aerosol growth episode was observed, providing a unique opportunity to investigate BSOA formation chemistry in a forested environment with limited influence from anthropogenic emissions. Positive matrix factorization of aerosol mass spectrometry (AMS measurement identified two types of BSOA (BSOA-1 and BSOA-2, which were primarily generated by gas-phase oxidation of monoterpenes and perhaps sesquiterpenes. The temporal variations of BSOA-1 and BSOA-2 can be explained by gas–particle partitioning in response to ambient temperature and the relative importance of different oxidation mechanisms between day and night. While BSOA-1 arises from gas-phase ozonolysis and nitrate radical chemistry at night, BSOA-2 is likely less volatile than BSOA-1 and consists of products formed via gas-phase oxidation by OH radical and ozone during the day. Organic nitrates produced through nitrate radical chemistry can account for 22–33 % of BSOA-1 mass at night. The mass spectra of BSOA-1 and BSOA-2 have higher values of the mass fraction of m/z 91 (f91 compared to the background organic aerosol. Using f91 to evaluate BSOA formation pathways in this unpolluted, forested region, heterogeneous oxidation of BSOA-1 is a minor production pathway of BSOA-2.

Indirect estimations and spatial variation in leaf area index of coniferous, deciduous and mixed forest stands in Forsmark and Laxemar

International Nuclear Information System (INIS)

Tagesson, Torbern

2006-12-01

Two sites in Sweden are investigated for a potential deep repository of the nuclear waste, the Laxemar investigation area (57 deg 5 min N, 16 deg 7 min E) and the Forsmark investigation area (60 deg 4 min N, 18 deg 2 min E). In the characterisation of these sites, development of site descriptive models is an important part. Leaves are the main surface were an exchange of matter and energy between the atmosphere and the biosphere takes place, and leaf area index (LAI) of the vegetation cover is an important variable correlated to a number of ecophysiological parameters and hereby an important parameter in ecosystem models. In the investigation areas, LAI of boreal and temperate ecosystems were therefore estimated indirectly through optical measurements using the LAI-2000 (LI-COR, Cambridge UK) and TRAC (Tracing Radiation and Architecture of Canopies). On average, measured maximum LAI was 3.40 in Laxemar and 3.43 in Forsmark; minimum LAI was 1.65 in Laxemar and 1.97 in Forsmark. Forest inventory data showed that LAI is positively correlated with basal area, stand height, stand volume and breast height tree diameter. For the coniferous stands, there was also a linearly negative relationship with age. In the Laxemar investigation area, there were no significant relationships for LAI with a satellite derived kNN (kNearest Neighbor) data set with stand height, stand volume and stand age. The kNN data set can therefore not be used to extrapolate measured LAI over the Laxemar investigation area. There were significant relationships between LAI and the normalized difference vegetation index (NDVI) for coniferous, deciduous and mixed forest stands in the Laxemar investigation area. A NDVI image could be used to extrapolate LAI over the entire investigation area. For the Forsmark investigation area, effective LAI for all stands were correlated to NDVI and this relationship could then be used for extrapolation. The effective LAI image was afterwards corrected for average

Indirect estimations and spatial variation in leaf area index of coniferous, deciduous and mixed forest stands in Forsmark and Laxemar

Energy Technology Data Exchange (ETDEWEB)

Tagesson, Torbern [Dept. of Physical Geography and Ecosystem Analysis, Lund Univ., Lund (Sweden)

2006-12-15

Two sites in Sweden are investigated for a potential deep repository of the nuclear waste, the Laxemar investigation area (57 deg 5 min N, 16 deg 7 min E) and the Forsmark investigation area (60 deg 4 min N, 18 deg 2 min E). In the characterisation of these sites, development of site descriptive models is an important part. Leaves are the main surface were an exchange of matter and energy between the atmosphere and the biosphere takes place, and leaf area index (LAI) of the vegetation cover is an important variable correlated to a number of ecophysiological parameters and hereby an important parameter in ecosystem models. In the investigation areas, LAI of boreal and temperate ecosystems were therefore estimated indirectly through optical measurements using the LAI-2000 (LI-COR, Cambridge UK) and TRAC (Tracing Radiation and Architecture of Canopies). On average, measured maximum LAI was 3.40 in Laxemar and 3.43 in Forsmark; minimum LAI was 1.65 in Laxemar and 1.97 in Forsmark. Forest inventory data showed that LAI is positively correlated with basal area, stand height, stand volume and breast height tree diameter. For the coniferous stands, there was also a linearly negative relationship with age. In the Laxemar investigation area, there were no significant relationships for LAI with a satellite derived kNN (kNearest Neighbor) data set with stand height, stand volume and stand age. The kNN data set can therefore not be used to extrapolate measured LAI over the Laxemar investigation area. There were significant relationships between LAI and the normalized difference vegetation index (NDVI) for coniferous, deciduous and mixed forest stands in the Laxemar investigation area. A NDVI image could be used to extrapolate LAI over the entire investigation area. For the Forsmark investigation area, effective LAI for all stands were correlated to NDVI and this relationship could then be used for extrapolation. The effective LAI image was afterwards corrected for average

Incubation of air-pollution-control residues from secondary Pb smelter in deciduous and coniferous organic soil horizons: leachability of lead, cadmium and zinc.

Science.gov (United States)

Chrastný, Vladislav; Vaněk, Aleš; Komárek, Michael; Farkaš, Juraj; Drábek, Ondřej; Vokurková, Petra; Němcová, Jana

2012-03-30

The leachability of air-pollution-control (APC) residues from a secondary lead smelter in organic soil horizons (F and H) from a deciduous and a coniferous forest during incubation periods of 0, 3 and 6 months were compared in this work. While the concentration of Pb, Zn and Cd associated with the exchangeable/acid extractable fraction in the horizon F from the coniferous forest was higher compared to the deciduous, significantly lower concentrations in the humified horizon H was found. It is suggested that lower pH and a higher share of fulvic acids fraction (FAs) of solid phase soil organic matter (SOM) in the humified soil horizon H from the coniferous compared to the deciduous forest is responsible for a higher metal association with solid phase SOM and therefore a lower metal leaching in a soil system. From this point of view, the humified soil horizon H from the deciduous forest represents a soil system more vulnerable to Pb, Zn and Cd leaching from APC residues. Copyright © 2012 Elsevier B.V. All rights reserved.

First megafossil evidence of Cyatheaceous tree fern from the Indian

Indian Academy of Sciences (India)

A part of the compressed tree fern axis with leaf and adventitious root scars in unusual arrangement from Plio–Pleistocene sediments of Arunachal Pradesh, India is described as Cyathea siwalika sp. nov. This record suggests that Cyathea was an important component of tropical evergreen forest in the area during the ...

Biodiversity and spatial distribution of epiphytic ferns on Alsophila setosa Kaulf. (Cyatheaceae) caudices in Rio Grande do Sul, Brazil.

Science.gov (United States)

Schmitt, J L; Windisch, P G

2010-08-01

The extractive exploitation of the tree fern Alsophila setosa Kaulf. alters forest formations and diminishes the availability of micro-habitat for epiphytes. A survey of epiphytic fern communities on A. setosa at 16 study sites in different forest formations in the State of Rio Grande do Sul, Brazil, documented the occurrence of 31 species representing 16 genera and six families. The greatest richness of species occurred in Polypodiaceae (39%) and in the genus Asplenium L. (22%). Habitual holoepiphyte was the predominant ecological category, representing 61% of the species. Similarity analysis demonstrated heterogeneity in the composition of the epiphytic ferns at the study sites and indicated that the vegetation type is not the main factor for floristic difference. The lowest total specific richness (5) was recorded for the seasonal deciduous forest site. The majority of the sites presented similar averages of phorophyte height and epiphyte richness per caudex. In 25% of the sites the height of the host plants presented significant correlation with specific richness. Considering that the majority of the epiphytes are habitual and that some of them occur exclusively or preferentially on tree ferns, the maintenance of these host plants in the vegetation is essential for the conservation of epiphytic species.

Biodiversity and spatial distribution of epiphytic ferns on Alsophila setosa Kaulf. (Cyatheaceae caudices in Rio Grande do Sul, Brazil

Directory of Open Access Journals (Sweden)

JL. Schmitt

Full Text Available The extractive exploitation of the tree fern Alsophila setosa Kaulf. alters forest formations and diminishes the availability of micro-habitat for epiphytes. A survey of epiphytic fern communities on A. setosa at 16 study sites in different forest formations in the State of Rio Grande do Sul, Brazil, documented the occurrence of 31 species representing 16 genera and six families. The greatest richness of species occurred in Polypodiaceae (39% and in the genus Asplenium L. (22%. Habitual holoepiphyte was the predominant ecological category, representing 61% of the species. Similarity analysis demonstrated heterogeneity in the composition of the epiphytic ferns at the study sites and indicated that the vegetation type is not the main factor for floristic difference. The lowest total specific richness (5 was recorded for the seasonal deciduous forest site. The majority of the sites presented similar averages of phorophyte height and epiphyte richness per caudex. In 25% of the sites the height of the host plants presented significant correlation with specific richness. Considering that the majority of the epiphytes are habitual and that some of them occur exclusively or preferentially on tree ferns, the maintenance of these host plants in the vegetation is essential for the conservation of epiphytic species.

Assessing seasonality of biochemical CO2 exchange model parameters from micrometeorological flux observations at boreal coniferous forest

Directory of Open Access Journals (Sweden)

T. Vesala

2008-12-01

Full Text Available The seasonality of the NEE of the northern boreal coniferous forests was investigated by means of inversion modelling using eddy covariance data. Eddy covariance data was used to optimize the biochemical model parameters. Our study sites consisted of three Scots pine (l. Pinus sylvestris forests and one Norway spruce (l. Picea abies forest that were located in Finland and Sweden. We obtained temperature and seasonal dependence for the biochemical model parameters: the maximum rate of carboxylation (Vc(max and the maximum rate of electron transport (Jmax. Both of the parameters were optimized without assumptions about their mutual magnitude. The values obtained for the biochemical model parameters were similar at all the sites during summer time. To describe seasonality, different temperature fits were made for the spring, summer and autumn periods. During summer, average Jmax across the sites was 54.0 μmol m−2 s−1 (variance 31.2 μmol m−2 s−1 and Vc(max was 12.0 μmol m−2 s−1 (variance 6.6 μmol m−2 s−1 at 17°C. The sensitivity of the model to LAI and atmospheric soil water stress was also studied. The impact of seasonality on annual GPP was 17% when only summertime parameterization was used throughout the year compared to seasonally changing parameterizations.

Assessment of Soil Water Composition in the Northern Taiga Coniferous Forests of Background Territories in the Industrially Developed Region

Science.gov (United States)

Lukina, N. V.; Ershov, V. V.; Gorbacheva, T. T.; Orlova, M. A.; Isaeva, L. G.; Teben'kova, D. N.

2018-03-01

The composition of soil water under coniferous forests of Murmansk oblast—an industrially developed region of northern Russia—was investigated. The studied objects were dwarf-shrub-green-moss spruce forests and dwarf-shrub-lichen pine forests on Al-Fe-humus podzols ( Albic Rustic Podzols) that are widespread in the boreal zone. The concentrations and removal of organic carbon performing the most important biogeochemical and pedogenic functions were estimated. The results proved significant intra- and inter-biogeocenotic variability in the composition of atmospheric depositions and soil water. Carbon removal with soil water from organic and mineral horizons within elementary biogeoareas (EBGA) under tree crowns was 2-5 and 2-3 times (in some cases, up to 10 times) greater than that in the intercrown areas, respectively. The lowest critical level of mineral nitrogen (0.2 mg/L) was, as a rule, exceeded in tree EBGAs contrary to intercrown areas. Concentrations of sulfates and heavy metals in water of tree EBGA were 3-5 times greater than those in inter-crown areas. Significant inter-biogeocenotic variations related to differences in the height of trees and tree stand density were found. It is argued that adequate characterization of biochemical cycles and assessment of critical levels of components in soil water of forest ecosystems should be performed with due account for the intra- and inter-biogeocenotic variability.

Head balance of coniferous forest in years with extreme precipitation and its long-term changes in the regions of Bydgoszcz and Wroclaw

International Nuclear Information System (INIS)

Bubnowska, J.; Gąsiorek, E.; Łabędzki, L.; Musiał, E.

2005-01-01

Climate changes, particularly visible in the last decades of the 20th century have paramount influence on human economic activity. Heat balance is one of the factors affecting the climate. That impact is noticeable when variations in heat balance components are examined e.g. in coniferous forest. This paper presents analyses of these variations during the growing season (III-X) in the years with maximal and minimal precipitation sums. The study shows also the changes in heat balance components in Wroclaw-Swojec in the years 1964-2000 and in Bydgoszcz in the years 1945-2003 [pl

Fern inventorization in Laiwangi-Wanggameti National Park, East Sumba, Waingapu, NTT

Directory of Open Access Journals (Sweden)

I NYOMAN PENENG

2007-07-01

Full Text Available The inventory and the collection of the ferns in Laiwangi-Wanggameti National Park will be plamted as collection plants in Bali Botanical Garden. In this research used the explorative method. The result of the research has collected 70 numbers of the ferns and 229 speciment. They consist of 21 family, 30 genus.and 70 species. From 70 species. There are 3 species such as Licopodium sernuum, Lygodium javanicum (Tumb. Sw. and Ophioglossum pendulum L. are predicted as new collection for the Bali Botanic Garden. The dominant genus in Laiwangi- Wanggameti National Park was Cyclosorus, Asplenium, Athyrium, and Pteris. Which are growing to cover the basic of the forest in damp places at the river bank.

Rehabilitation of monotonous exotic coniferous plantations: a case study of spontaneous establishment of different tree species

Czech Academy of Sciences Publication Activity Database

Jonášová, Magda; van Hees, A.; Prach, Karel

-, č. 28 (2006), s. 141-148 ISSN 0925-8574 Institutional research plan: CEZ:AV0Z60870520; CEZ:AV0Z60050516 Keywords : restoration of coniferous plantations * natural regeneration * forest management Subject RIV: GK - Forestry Impact factor: 1.331, year: 2006

Factor contribution to fire occurrence, size, and burn probability in a subtropical coniferous forest in East China.

Science.gov (United States)

Ye, Tao; Wang, Yao; Guo, Zhixing; Li, Yijia

2017-01-01

The contribution of factors including fuel type, fire-weather conditions, topography and human activity to fire regime attributes (e.g. fire occurrence, size distribution and severity) has been intensively discussed. The relative importance of those factors in explaining the burn probability (BP), which is critical in terms of fire risk management, has been insufficiently addressed. Focusing on a subtropical coniferous forest with strong human disturbance in East China, our main objective was to evaluate and compare the relative importance of fuel composition, topography, and human activity for fire occurrence, size and BP. Local BP distribution was derived with stochastic fire simulation approach using detailed historical fire data (1990-2010) and forest-resource survey results, based on which our factor contribution analysis was carried out. Our results indicated that fuel composition had the greatest relative importance in explaining fire occurrence and size, but human activity explained most of the variance in BP. This implies that the influence of human activity is amplified through the process of overlapping repeated ignition and spreading events. This result emphasizes the status of strong human disturbance in local fire processes. It further confirms the need for a holistic perspective on factor contribution to fire likelihood, rather than focusing on individual fire regime attributes, for the purpose of fire risk management.

OZONE AND SULFUR DIOXIDE DRY DEPOSITION TO FORESTS: OBSERVATIONS AND MODEL EVALUATION

Science.gov (United States)

Fluxes and deposition velocities of O3 and SO2 were measured over both a deciduous and a mixed coniferous-deciduous forest for full growing seasons. Fluxes and deposition velocities of O3 were measured over a coniferous forest for a month. Mean deposition velocities of 0.35 t...

Alsophila weidenbrueckii (Cyatheaceae), a new scaly tree fern from Papua New Guinea

NARCIS (Netherlands)

Lehnert, M.

2016-01-01

The scaly tree fern Alsophila weidenbrueckii is described and illustrated as new to science. It occurs in the Bismarck range in north-eastern New Guinea at 1200–2100 m in evergreen wet mountain forest. The species reaches maturity at a comparatively old age and large size and regenerates only in

Complete chloroplast genome sequence of a tree fern Alsophila spinulosa: insights into evolutionary changes in fern chloroplast genomes.

Science.gov (United States)

Gao, Lei; Yi, Xuan; Yang, Yong-Xia; Su, Ying-Juan; Wang, Ting

2009-06-11

Ferns have generally been neglected in studies of chloroplast genomics. Before this study, only one polypod and two basal ferns had their complete chloroplast (cp) genome reported. Tree ferns represent an ancient fern lineage that first occurred in the Late Triassic. In recent phylogenetic analyses, tree ferns were shown to be the sister group of polypods, the most diverse group of living ferns. Availability of cp genome sequence from a tree fern will facilitate interpretation of the evolutionary changes of fern cp genomes. Here we have sequenced the complete cp genome of a scaly tree fern Alsophila spinulosa (Cyatheaceae). The Alsophila cp genome is 156,661 base pairs (bp) in size, and has a typical quadripartite structure with the large (LSC, 86,308 bp) and small single copy (SSC, 21,623 bp) regions separated by two copies of an inverted repeat (IRs, 24,365 bp each). This genome contains 117 different genes encoding 85 proteins, 4 rRNAs and 28 tRNAs. Pseudogenes of ycf66 and trnT-UGU are also detected in this genome. A unique trnR-UCG gene (derived from trnR-CCG) is found between rbcL and accD. The Alsophila cp genome shares some unusual characteristics with the previously sequenced cp genome of the polypod fern Adiantum capillus-veneris, including the absence of 5 tRNA genes that exist in most other cp genomes. The genome shows a high degree of synteny with that of Adiantum, but differs considerably from two basal ferns (Angiopteris evecta and Psilotum nudum). At one endpoint of an ancient inversion we detected a highly repeated 565-bp-region that is absent from the Adiantum cp genome. An additional minor inversion of the trnD-GUC, which is possibly shared by all ferns, was identified by comparison between the fern and other land plant cp genomes. By comparing four fern cp genome sequences it was confirmed that two major rearrangements distinguish higher leptosporangiate ferns from basal fern lineages. The Alsophila cp genome is very similar to that of the

Complete chloroplast genome sequence of a tree fern Alsophila spinulosa: insights into evolutionary changes in fern chloroplast genomes

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Yang Yong-Xia

2009-06-01

Full Text Available Abstract Background Ferns have generally been neglected in studies of chloroplast genomics. Before this study, only one polypod and two basal ferns had their complete chloroplast (cp genome reported. Tree ferns represent an ancient fern lineage that first occurred in the Late Triassic. In recent phylogenetic analyses, tree ferns were shown to be the sister group of polypods, the most diverse group of living ferns. Availability of cp genome sequence from a tree fern will facilitate interpretation of the evolutionary changes of fern cp genomes. Here we have sequenced the complete cp genome of a scaly tree fern Alsophila spinulosa (Cyatheaceae. Results The Alsophila cp genome is 156,661 base pairs (bp in size, and has a typical quadripartite structure with the large (LSC, 86,308 bp and small single copy (SSC, 21,623 bp regions separated by two copies of an inverted repeat (IRs, 24,365 bp each. This genome contains 117 different genes encoding 85 proteins, 4 rRNAs and 28 tRNAs. Pseudogenes of ycf66 and trnT-UGU are also detected in this genome. A unique trnR-UCG gene (derived from trnR-CCG is found between rbcL and accD. The Alsophila cp genome shares some unusual characteristics with the previously sequenced cp genome of the polypod fern Adiantum capillus-veneris, including the absence of 5 tRNA genes that exist in most other cp genomes. The genome shows a high degree of synteny with that of Adiantum, but differs considerably from two basal ferns (Angiopteris evecta and Psilotum nudum. At one endpoint of an ancient inversion we detected a highly repeated 565-bp-region that is absent from the Adiantum cp genome. An additional minor inversion of the trnD-GUC, which is possibly shared by all ferns, was identified by comparison between the fern and other land plant cp genomes. Conclusion By comparing four fern cp genome sequences it was confirmed that two major rearrangements distinguish higher leptosporangiate ferns from basal fern lineages. The

Richness, geographic distribution and ecological aspects of the fern community within the Murici Ecological Station in the state of Alagoas, Brazil

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Anna Flora de Novaes Pereira

2013-12-01

Full Text Available We conducted a floristic survey of ferns within the Murici Ecological Station (remnant of the northeastern Atlantic Forest, located near the municipalities of Messias and Murici, in the state of Alagoas, Brazil. To increase knowledge of the ferns of Alagoas, we evaluated the species occurring in the study area in terms of richness, composition, geographic distribution, similarities with species in other Brazilian biomes, regional conservation status and ecological aspects. Data were obtained from field work conducted between March 2009 and September 2010. We identified 107 species of ferns, of which 19 represent new records for Alagoas. The richest families were Pteridaceae (29 species and Polypodiaceae (22 species. The richest genera were Adiantum (15 species and Thelypteris (9 species. Most of the species sampled are widely distributed throughout Brazil and the Americas. Within the context of the northeastern Atlantic Forest, 12 species were considered endangered. Concerning the ecological aspects, 88.8% of the species identified were herbaceous, 57.9% were terrestrial and 70.0% occurred in the forest interior.

BASIC CONCEPTS AND METHODS OF RESTORATION OF NATURAL FORESTS IN EASTERN EUROPE

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V. N. Korotkov

2017-03-01

Full Text Available The modern forest in coniferous-broadleaf (hemiboreal and broadleaf zones of Eastern Europe were formed as a result of long-term human impact. This led to the loss of natural forests and total dominance of secondary forests combined with monocultures of spruce and pine that were created in clearings, burned areas and fallow lands. The reforestation model that was common in the late XIX and first half of the XX century and that was focused on the establishment of monocultures commercially valuable coniferous tree species (spruce and pine over large areas has resulted in declining biological diversity, increasing risk of tree damage due to outbreaks of pathogens and phytophagous insects, decreasing soil fertility, worsening soil and water conservation functions of forests. When restoring the prototypes of natural forests it is necessary to be guided by the modern concepts of synecology and model reconstructions of forest cover in pre-anthropogenic period that are briefly discussed in the paper. Based on the analysis of literature and research experience the author proposes the concept of natural forest restoration that can be applied primarily to the coniferous-broadleaf and broadleaf forests. The main goal is to create multiple-aged and polydominant near-natural forest ecosystems with higher resistance to fungal diseases and outbreaks of phytophagous insects. The field of concept application is specially protected natural areas (national parks, natural parks, wildlife sanctuaries, etc., different categories of protective forests located within the zones of coniferous-broadleaf and broadleaf forests on the East European Plain. The formation of multiple-aged forests is possible when group felling and group-clear felling that largely imitate the natural gap-mosaic stand are implemented. The formation of new generations of trees is possible both due to the natural regeneration and the development of forest cultures. The article provides the full set

N-15 tracing helps explaining N leaching losses from contrasting forest ecosystems

Science.gov (United States)

Staelens, J.; Rütting, T.; Huygens, D.; Müller, C.; Verheyen, K.; Boeckx, P.

2009-04-01

Despite chronically enhanced nitrogen (N) deposition to forest ecosystems in Europe and NE America, considerable N retention by forests has been observed, reducing N leaching losses. Organic and mineral soil layers typically immobilize more N than the aboveground biomass, but it is unclear which factors determine N retention in forest ecoystems. However, this knowledge is crucial to assess the impact of changing anthropogenic N emissions on future N cycling and N loss of forests. For coniferous and deciduous forest stands at comparable sites, it is known that both N deposition onto the forest floor as well as N loss by leaching below the rooting zone are significantly higher in coniferous stands. In addition, the N loss in coniferous stands is often more enhanced than can be explained by the higher N input only. This suggests lower N retention by coniferous stands, and may be related to differences in litter and soil characteristics, microbial activity, and N uptake by plant roots. To test this hypothesis, we studied the effect of forest type on N retention using 15N tracing techniques: a field tracer experiment and a combination of in situ isotope pool dilution and a tracing model. The N dynamics were examined for two adjacent forest stands (pedunculate oak (Quercus robur L.) and Scots pine (Pinus sylvestris L.)) on a well-drained sandy soil and with a similar stand history, located in a region with high N deposition (Belgium). Input-output N budgets were established by quantifying atmospheric deposition and leaching below the rooting zone, and confirmed the above finding of higher N deposition and disproportionately higher N loss for the pine stand compared to the oak stand. First, the fate of inorganic N within the ecosystems was studied by spraying three pulses of dissolved 15N, either as ammonium or as nitrate, onto the forest floor in 12 plots of 25 m2. The organic and mineral soil layers, tree roots, soil water percolate, ferns, and tree foliage were sampled

Net aboveground biomass declines of four major forest types with forest ageing and climate change in western Canada's boreal forests.

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Chen, Han Y H; Luo, Yong

2015-10-01

Biomass change of the world's forests is critical to the global carbon cycle. Despite storing nearly half of global forest carbon, the boreal biome of diverse forest types and ages is a poorly understood component of the carbon cycle. Using data from 871 permanent plots in the western boreal forest of Canada, we examined net annual aboveground biomass change (ΔAGB) of four major forest types between 1958 and 2011. We found that ΔAGB was higher for deciduous broadleaf (DEC) (1.44 Mg ha(-1)  year(-1) , 95% Bayesian confidence interval (CI), 1.22-1.68) and early-successional coniferous forests (ESC) (1.42, CI, 1.30-1.56) than mixed forests (MIX) (0.80, CI, 0.50-1.11) and late-successional coniferous (LSC) forests (0.62, CI, 0.39-0.88). ΔAGB declined with forest age as well as calendar year. After accounting for the effects of forest age, ΔAGB declined by 0.035, 0.021, 0.032 and 0.069 Mg ha(-1)  year(-1) per calendar year in DEC, ESC, MIX and LSC forests, respectively. The ΔAGB declines resulted from increased tree mortality and reduced growth in all forest types except DEC, in which a large biomass loss from mortality was accompanied with a small increase in growth. With every degree of annual temperature increase, ΔAGB decreased by 1.00, 0.20, 0.55 and 1.07 Mg ha(-1)  year(-1) in DEC, ESC, MIX and LSC forests, respectively. With every cm decrease of annual climatic moisture availability, ΔAGB decreased 0.030, 0.045 and 0.17 Mg ha(-1)  year(-1) in ESC, MIX and LSC forests, but changed little in DEC forests. Our results suggest that persistent warming and decreasing water availability have profound negative effects on forest biomass in the boreal forests of western Canada. Furthermore, our results indicate that forest responses to climate change are strongly dependent on forest composition with late-successional coniferous forests being most vulnerable to climate changes in terms of aboveground biomass. © 2015 John Wiley & Sons Ltd.

Carbon in boreal coniferous forest soil

Energy Technology Data Exchange (ETDEWEB)

Westman, C J; Ilvesniemi, H; Liski, J; Mecke, M [Helsinki Univ. (Finland). Dept. of Forest Ecology; Fritze, H; Helmisaari, H S; Pietikaeinen, J; Smolander, A [Finnish Forest Research Inst., Vantaa (Finland)

1997-12-31

The working hypothesis of the research was that the soil of boreal forests is a large carbon store and the amount of C is still increasing in young soils, like in the forest soils of Finland, which makes these soils important sinks for atmospheric CO{sub 2}. Since the processes defining the soil C balance, primary production of plants and decomposition, are dependent on environmental factors and site properties, it was assumed that the organic carbon pool in the soil is also dependent on the same factors. The soil C store is therefore likely to change in response to climatic warming. The aim of this research was to estimate the C balance of forest soil in Finland and predict changes in the balance in response to changes in climatic conditions. To achieve the aim (1) intensive empirical experimentation on the density of C in different pools in the soil and on fluxes between the pools was done was done, (2) the effect of site fertility and climate on the amount and properties of organic C in forest soil was investigated and (3) dynamic modelling for investigating dynamics of the soil C storage was used

Carbon in boreal coniferous forest soil

Energy Technology Data Exchange (ETDEWEB)

Westman, C.J.; Ilvesniemi, H.; Liski, J.; Mecke, M. [Helsinki Univ. (Finland). Dept. of Forest Ecology; Fritze, H.; Helmisaari, H.S.; Pietikaeinen, J.; Smolander, A. [Finnish Forest Research Inst., Vantaa (Finland)

1996-12-31

The working hypothesis of the research was that the soil of boreal forests is a large carbon store and the amount of C is still increasing in young soils, like in the forest soils of Finland, which makes these soils important sinks for atmospheric CO{sub 2}. Since the processes defining the soil C balance, primary production of plants and decomposition, are dependent on environmental factors and site properties, it was assumed that the organic carbon pool in the soil is also dependent on the same factors. The soil C store is therefore likely to change in response to climatic warming. The aim of this research was to estimate the C balance of forest soil in Finland and predict changes in the balance in response to changes in climatic conditions. To achieve the aim (1) intensive empirical experimentation on the density of C in different pools in the soil and on fluxes between the pools was done was done, (2) the effect of site fertility and climate on the amount and properties of organic C in forest soil was investigated and (3) dynamic modelling for investigating dynamics of the soil C storage was used

Ferns diversified in the shadow of angiosperms.

Science.gov (United States)

Schneider, Harald; Schuettpelz, Eric; Pryer, Kathleen M; Cranfill, Raymond; Magallón, Susana; Lupia, Richard

2004-04-01

The rise of angiosperms during the Cretaceous period is often portrayed as coincident with a dramatic drop in the diversity and abundance of many seed-free vascular plant lineages, including ferns. This has led to the widespread belief that ferns, once a principal component of terrestrial ecosystems, succumbed to the ecological predominance of angiosperms and are mostly evolutionary holdovers from the late Palaeozoic/early Mesozoic era. The first appearance of many modern fern genera in the early Tertiary fossil record implies another evolutionary scenario; that is, that the majority of living ferns resulted from a more recent diversification. But a full understanding of trends in fern diversification and evolution using only palaeobotanical evidence is hindered by the poor taxonomic resolution of the fern fossil record in the Cretaceous. Here we report divergence time estimates for ferns and angiosperms based on molecular data, with constraints from a reassessment of the fossil record. We show that polypod ferns (> 80% of living fern species) diversified in the Cretaceous, after angiosperms, suggesting perhaps an ecological opportunistic response to the diversification of angiosperms, as angiosperms came to dominate terrestrial ecosystems.

Grass or fern competition reduce growth and survival of planted tree seedlings

Science.gov (United States)

Larry H. McCormick; Todd W. Bowersox

1997-01-01

Bareroot seedlings of northern red oak, white ash, yellow-poplar and white pine were planted into herbaceous communities at three forested sites in central Pennsylvania that were clearcut 0 to 1 year earlier. Seedlings were grown 4 years in the presence and absence of either an established grass or hay-scented fern community. Survival and height growth were measured...

Effects of land use and fine-scale environmental heterogeneity on net ecosystem production over a temperate coniferous forest landscape

Energy Technology Data Exchange (ETDEWEB)

Turner, David P.; Guzy, Michael; Lefsky, Michael A.; Tuyl, Steve van; Sun, Osbert; Law, Beverly E. [Oregon State Univ. Corvallis, OR (United States). Dept. of Forest Science; Daly, Chris [Oregon State Univ., Corvallis, OR (United States). Dept. of Geosciences

2003-04-01

In temperate coniferous forests, spatial variation in net ecosystem production (NEP) is often associated with variation in stand age and heterogeneity in environmental factors such as soil depth. However, coarse spatial resolution analyses used to evaluate the terrestrial contribution to global NEP do not generally incorporate these effects. In this study, a fine-scale (25 m grid) analysis of NEP over a 164-km{sup 2} area of productive coniferous forests in the Pacific Northwest region of the United States was made to evaluate the effects of including fine scale information in landscape-scale NEP assessments. The Enhanced Thematic Mapper (ETM+) sensor resolved five cover classes in the study area and further differentiated between young, mature and old-growth conifer stands. ETM+ was also used to map current leaf area index (LAI) based on an empirical relationship of observed LAI to spectral vegetation indices. A daily time step climatology, based on 18 years of meteorological observations, was distributed (1 km resolution) over the mountainous terrain of the study area using the DAYMET model. Estimates of carbon pools and flux associated with soil, litter, coarse woody debris and live trees were then generated by running a carbon cycle model (Biome-BGC) to a state that reflected the current successional status and LAI of each grid cell, as indicated by the remote sensing observations. Estimated annual NEP for 1997 over the complete study area averaged 230 g C m{sup 2}, with most of the area acting as a carbon sink. The area-wide NEP is strongly positive because of reduced harvesting in the last decade and the recovery of areas harvested between 1940 and 1990. The average value was greater than would be indicated if the entire area was assumed to be a mature conifer stand, as in a coarse-scale analysis. The mean NEP varied interannually by over a factor of two. This variation was 38% less than the interannual variation for a single point. The integration of process

Effects of land use and fine-scale environmental heterogeneity on net ecosystem production over a temperate coniferous forest landscape

International Nuclear Information System (INIS)

Turner, David P.; Guzy, Michael; Lefsky, Michael A.; Tuyl, Steve van; Sun, Osbert; Law, Beverly E.; Daly, Chris

2003-01-01

In temperate coniferous forests, spatial variation in net ecosystem production (NEP) is often associated with variation in stand age and heterogeneity in environmental factors such as soil depth. However, coarse spatial resolution analyses used to evaluate the terrestrial contribution to global NEP do not generally incorporate these effects. In this study, a fine-scale (25 m grid) analysis of NEP over a 164-km 2 area of productive coniferous forests in the Pacific Northwest region of the United States was made to evaluate the effects of including fine scale information in landscape-scale NEP assessments. The Enhanced Thematic Mapper (ETM+) sensor resolved five cover classes in the study area and further differentiated between young, mature and old-growth conifer stands. ETM+ was also used to map current leaf area index (LAI) based on an empirical relationship of observed LAI to spectral vegetation indices. A daily time step climatology, based on 18 years of meteorological observations, was distributed (1 km resolution) over the mountainous terrain of the study area using the DAYMET model. Estimates of carbon pools and flux associated with soil, litter, coarse woody debris and live trees were then generated by running a carbon cycle model (Biome-BGC) to a state that reflected the current successional status and LAI of each grid cell, as indicated by the remote sensing observations. Estimated annual NEP for 1997 over the complete study area averaged 230 g C m 2 , with most of the area acting as a carbon sink. The area-wide NEP is strongly positive because of reduced harvesting in the last decade and the recovery of areas harvested between 1940 and 1990. The average value was greater than would be indicated if the entire area was assumed to be a mature conifer stand, as in a coarse-scale analysis. The mean NEP varied interannually by over a factor of two. This variation was 38% less than the interannual variation for a single point. The integration of process models

Forest influences on snow accumulation and snowmelt at the Hubbard Brook Experimental Forest, New Hampshire, USA

Science.gov (United States)

Colin A. Penn; Beverley C. Wemple; John L. Campbell

2012-01-01

Many factors influence snow depth, water content and duration in forest ecosystems. The effects of forest cover and canopy gap geometry on snow accumulation has been well documented in coniferous forests of western North America and other regions; however, few studies have evaluated these effects on snowpack dynamics in mixed deciduous forests of the northeastern USA....

Trends and concepts in fern classification

Science.gov (United States)

Christenhusz, Maarten J. M.; Chase, Mark W.

2014-01-01

Background and Aims Throughout the history of fern classification, familial and generic concepts have been highly labile. Many classifications and evolutionary schemes have been proposed during the last two centuries, reflecting different interpretations of the available evidence. Knowledge of fern structure and life histories has increased through time, providing more evidence on which to base ideas of possible relationships, and classification has changed accordingly. This paper reviews previous classifications of ferns and presents ideas on how to achieve a more stable consensus. Scope An historical overview is provided from the first to the most recent fern classifications, from which conclusions are drawn on past changes and future trends. The problematic concept of family in ferns is discussed, with a particular focus on how this has changed over time. The history of molecular studies and the most recent findings are also presented. Key Results Fern classification generally shows a trend from highly artificial, based on an interpretation of a few extrinsic characters, via natural classifications derived from a multitude of intrinsic characters, towards more evolutionary circumscriptions of groups that do not in general align well with the distribution of these previously used characters. It also shows a progression from a few broad family concepts to systems that recognized many more narrowly and highly controversially circumscribed families; currently, the number of families recognized is stabilizing somewhere between these extremes. Placement of many genera was uncertain until the arrival of molecular phylogenetics, which has rapidly been improving our understanding of fern relationships. As a collective category, the so-called ‘fern allies’ (e.g. Lycopodiales, Psilotaceae, Equisetaceae) were unsurprisingly found to be polyphyletic, and the term should be abandoned. Lycopodiaceae, Selaginellaceae and Isoëtaceae form a clade (the lycopods) that is

Trends and concepts in fern classification.

Science.gov (United States)

Christenhusz, Maarten J M; Chase, Mark W

2014-03-01

Throughout the history of fern classification, familial and generic concepts have been highly labile. Many classifications and evolutionary schemes have been proposed during the last two centuries, reflecting different interpretations of the available evidence. Knowledge of fern structure and life histories has increased through time, providing more evidence on which to base ideas of possible relationships, and classification has changed accordingly. This paper reviews previous classifications of ferns and presents ideas on how to achieve a more stable consensus. An historical overview is provided from the first to the most recent fern classifications, from which conclusions are drawn on past changes and future trends. The problematic concept of family in ferns is discussed, with a particular focus on how this has changed over time. The history of molecular studies and the most recent findings are also presented. Fern classification generally shows a trend from highly artificial, based on an interpretation of a few extrinsic characters, via natural classifications derived from a multitude of intrinsic characters, towards more evolutionary circumscriptions of groups that do not in general align well with the distribution of these previously used characters. It also shows a progression from a few broad family concepts to systems that recognized many more narrowly and highly controversially circumscribed families; currently, the number of families recognized is stabilizing somewhere between these extremes. Placement of many genera was uncertain until the arrival of molecular phylogenetics, which has rapidly been improving our understanding of fern relationships. As a collective category, the so-called 'fern allies' (e.g. Lycopodiales, Psilotaceae, Equisetaceae) were unsurprisingly found to be polyphyletic, and the term should be abandoned. Lycopodiaceae, Selaginellaceae and Isoëtaceae form a clade (the lycopods) that is sister to all other vascular plants, whereas

Non-linear growth in tree ferns, Dicksonia antarctica and Cyathea australis.

Science.gov (United States)

Blair, David P; Blanchard, Wade; Banks, Sam C; Lindenmayer, David B

2017-01-01

Tree ferns are an important structural component of forests in many countries. However, because their regeneration is often unrelated to major disturbances, their age is often difficult to determine. In addition, rates of growth may not be uniform, which further complicates attempts to determine their age. In this study, we measured 5 years of growth of Cyathea australis and Dicksonia antarctica after a large wildfire in 2009 in south-eastern Australia. We found growth rates of these two species were unaffected by aspect and elevation but slope had a minor effect with D. antarctica growing 0.3mm faster for each additional degree of slope. Geographic location influenced growth in both species by up to 12 - 14mm/yr. The most consistent factor influencing growth rate, however, was initial height at the time of the 2009 fire; a finding consistent in both species and all geographic locations. For both tree fern species, individuals that were taller at the commencement of the study had greater overall growth for the duration of the study. This effect did not decrease even among the tallest tree ferns in our study (up to 6 metres tall). Overall, Cyathea australis averaged 73 (± 22)mm/year of growth (± 1SD), with the rate increasing 5mm/yr per metre of additional height. Dicksonia antarctica averaged 33 (± 13)mm/year, increasing by 6mm/yr/m. Growth rates dependent on initial height were unexpected and we discuss possible reasons for this finding. Variable growth rates also suggest that common age estimation methods of dividing height by average growth rate are likely to underestimate the age of short tree ferns, while overestimating the age of tall tree ferns, particularly if they have been subject to a fire.

Non-linear growth in tree ferns, Dicksonia antarctica and Cyathea australis.

Directory of Open Access Journals (Sweden)

David P Blair

Full Text Available Tree ferns are an important structural component of forests in many countries. However, because their regeneration is often unrelated to major disturbances, their age is often difficult to determine. In addition, rates of growth may not be uniform, which further complicates attempts to determine their age. In this study, we measured 5 years of growth of Cyathea australis and Dicksonia antarctica after a large wildfire in 2009 in south-eastern Australia. We found growth rates of these two species were unaffected by aspect and elevation but slope had a minor effect with D. antarctica growing 0.3mm faster for each additional degree of slope. Geographic location influenced growth in both species by up to 12 - 14mm/yr. The most consistent factor influencing growth rate, however, was initial height at the time of the 2009 fire; a finding consistent in both species and all geographic locations. For both tree fern species, individuals that were taller at the commencement of the study had greater overall growth for the duration of the study. This effect did not decrease even among the tallest tree ferns in our study (up to 6 metres tall. Overall, Cyathea australis averaged 73 (± 22mm/year of growth (± 1SD, with the rate increasing 5mm/yr per metre of additional height. Dicksonia antarctica averaged 33 (± 13mm/year, increasing by 6mm/yr/m. Growth rates dependent on initial height were unexpected and we discuss possible reasons for this finding. Variable growth rates also suggest that common age estimation methods of dividing height by average growth rate are likely to underestimate the age of short tree ferns, while overestimating the age of tall tree ferns, particularly if they have been subject to a fire.

Ecophysiological behaviour of hardwood species in renaturalization processes of coniferous plantations [Campania

International Nuclear Information System (INIS)

Borghetti, M.; Saracino, A.; D'Alessandro, C.M.

2005-01-01

Coniferous plantations may play a nurse effect for natural regeneration of native hardwood species, which would otherwise be conditioned by intraspecific competition due to trees of the upper layers or be prevented by high radiation load of open environments. Regulation of canopy cover by means of thinning generates temporary or permanent variations of levels of irradiance in lower forest layers. These affect the capability of recruitment and establishment and the ecophysiological behaviour of natural regeneration. Here we present a review of the notions on effects of relative irradiance variations on ecophysiological behaviour of native tree species in lower layers of mesophile and meso-xerophile forests, giving some specific examples produced during the national project PRIN 2003 FOR BIO [it

Stoichiometry of ferns in Hawaii: implications for nutrient cycling.

Science.gov (United States)

Amatangelo, Kathryn L; Vitousek, Peter M

2008-10-01

We asked if element concentrations in ferns differ systematically from those in woody dicots in ways that could influence ecosystem properties and processes. Phylogenetically, ferns are deeply separated from angiosperms; for our analyses we additionally separated leptosporangiate ferns into polypod ferns, a monophyletic clade of ferns which radiated after the rise of angiosperms, and all other leptosporangiate (non-polypod) ferns. We sampled both non-polypod and polypod ferns on a natural fertility gradient and within fertilized and unfertilized plots in Hawaii, and compared our data with shrub and tree samples collected previously in the same plots. Non-polypod ferns in particular had low Ca concentrations under all conditions and less plasticity in their N and P stoichiometry than did polypod ferns or dicots. Polypod ferns were particularly rich in N and P, with low N:P ratios, and their stoichiometry varied substantially in response to differences in nutrient availability. Distinguishing between these two groups has the potential to be useful both in and out of Hawaii, as they have distinct properties which can affect ecosystem function. These differences could contribute to the widespread abundance of polypod ferns in an angiosperm-dominated world, and to patterns of nutrient cycling and limitation in sites where ferns are abundant.

Micrometeorological measurement of the dry deposition flux of sulphate and nitrate aerosols to coniferous forest

NARCIS (Netherlands)

Wyers, G.P.; Duyzer, J.H.

1997-01-01

Dry deposition fluxes of sulphate and nitrate have been determined over a coniferous canopy using the aerodynamic gradient technique. Vertical concentration gradients of sulphate and nitrate were measured with filters; the gradient of ammonium bisulphate was measured with thermodenuders. Filter

High gene flow in epiphytic ferns despite habitat loss and fragmentation

OpenAIRE

Winkler, Manuela; Koch, Marcus; Hietz, Peter

2011-01-01

Tropical montane forests suffer from increasing fragmentation and replacement by other types of land-use such as coffee plantations. These processes are known to affect gene flow and genetic structure of plant populations. Epiphytes are particularly vulnerable because they depend on their supporting trees for their entire life-cycle. We compared population genetic structure and genetic diversity derived from AFLP markers of two epiphytic fern species differing in their ability to colonize sec...

Transfer of 137Cs from soil to plants in a wet montane forest in subtropical Taiwan

International Nuclear Information System (INIS)

Chih-Yu Chiu

1999-01-01

The distribution of 137 Cs in an undisturbed, multistoried, subtropical wet montane forest ecosystem surrounding Yuanyang Lake (lake surface level ca. 1670 m, in northeastern Taiwan), was investigated. The mossy forest here represents a currently-rare perhumid temperate environment in subtropical region. The radioactivity concentration of 137 Cs was determined by γ-spectroscopy with a Ge(Li) detector. Although the soil is extremely acidic (pH 3.3 to 3.6) and the rainfall is high, 137 Cs is evidently retained in the organic layer. The radioactivity concentration of 137 Cs in surface soil ranges from 28 to 71 Bq x kg -1 . The concentrations of 137 Cs in the ground moss layer and litter were much lower than that in the soil organic layer; this suggests that 137 Cs detected is not from the newly deposited radioactive fallout. The radioactivity concentration and transfer factor (TF) of 137 Cs varied with plant species. Shrubs and ferns have higher values than a coniferous tree (Taiwan cedar). The TF in this ecosystem is as high as 0.21 to 1.88. The high values of TF is attributed to the abundance of the organic matter in the forest soils. The rapid recycling of 137 Cs through the soil-plant system of this undisturbed multistoried ecosystem suggests the existence of an internal cycling that help the accumulation of 137 Cs in this ecosystem. (author)

Using EO-1 Hyperion to Simulate HyspIRI Products for a Coniferous Forest: The Fraction of PAR Absorbed by Chlorophyll (fAPAR(sub chl)) and Leaf Water Content(LWC)

Science.gov (United States)

Zhang, Qingyuan; Middleton, Elizabeth M.; Gao, Bo-Cai; Cheng, Yen-Ben

2012-01-01

This paper presents development of prototype products for terrestrial ecosystems in preparation for the future imaging spectrometer planned for the Hyperspectral Infrared Imager (HyspIRI) mission. We present a successful demonstration example in a coniferous forest of two product prototypes: fraction of photosynthetically active radiation (PAR) absorbed by chlorophyll of a canopy (fAPARchl) and leaf water content (LWC), for future HyspIRI implementation at 60-m spatial resolution. For this, we used existing 30-m resolution imaging spectrometer data available from the Earth Observing One (EO-1) Hyperion satellite to simulate and prototype the level one radiometrically corrected radiance (L1R) images expected from the HyspIRI visible through shortwave infrared spectrometer. The HyspIRIlike images were atmospherically corrected to obtain surface reflectance and spectrally resampled to produce 60-m reflectance images for wavelength regions that were comparable to all seven of the MODerate resolution Imaging Spectroradiometer (MODIS) land bands. Thus, we developed MODIS-like surface reflectance in seven spectral bands at the HyspIRI-like spatial scale, which was utilized to derive fAPARchl and LWC with a coupled canopy-leaf radiative transfer model (PROSAIL2) for the coniferous forest. With this paper, we provide additional evidence that the fAPARchl product is more realistic in describing the physiologically active canopy than the traditional fAPAR parameter for the whole canopy (fAPARcanopy), and thus, it should replace it in ecosystem process models to reduce uncertainties in terrestrial carbon cycle and ecosystem studies.

Factors controlling regional differences in forest soil emission of nitrogen oxides (NO and N2O

Directory of Open Access Journals (Sweden)

K. Pilegaard

2006-01-01

Full Text Available Soil emissions of NO and N2O were measured continuously at high frequency for more than one year at 15 European forest sites as part of the EU-funded project NOFRETETE. The locations represent different forest types (coniferous/deciduous and different nitrogen loads. Geographically they range from Finland in the north to Italy in the south and from Hungary in the east to Scotland in the west. The highest NO emissions were observed from coniferous forests, whereas the lowest NO emissions were observed from deciduous forests. The NO emissions from coniferous forests were highly correlated with N-deposition. The site with the highest average annual emission (82 μg NO-N m−2 h−1 was a spruce forest in South-Germany (Höglwald receiving an annual N-deposition of 2.9 g m−2. NO emissions close to the detection limit were observed from a pine forest in Finland where the N-deposition was 0.2 g N m−2 a−1. No significant correlation between N2O emission and N-deposition was found. The highest average annual N2O emission (20 μg N2O-N m−2 h−1 was found in an oak forest in the Mátra mountains (Hungary receiving an annual N-deposition of 1.6 g m−2. N2O emission was significantly negatively correlated with the C/N ratio. The difference in N-oxide emissions from soils of coniferous and deciduous forests may partly be explained by differences in N-deposition rates and partly by differences in characteristics of the litter layer and soil. NO was mainly derived from nitrification whereas N2O was mainly derived from denitrification. In general, soil moisture is lower at coniferous sites (at least during spring time and the litter layer of coniferous forests is thick and well aerated favouring nitrification and thus release of NO. Conversely, the higher rates of denitrification in deciduous forests due to a compact and moist litter layer lead to N2O production and NO consumption in the soil. The two factors soil moisture and soil temperature are

Non-linear growth in tree ferns, Dicksonia antarctica and Cyathea australis

OpenAIRE

Blair, David P.; Blanchard, Wade; Banks, Sam C.; Lindenmayer, David B.

2017-01-01

Tree ferns are an important structural component of forests in many countries. However, because their regeneration is often unrelated to major disturbances, their age is often difficult to determine. In addition, rates of growth may not be uniform, which further complicates attempts to determine their age. In this study, we measured 5 years of growth of Cyathea australis and Dicksonia antarctica after a large wildfire in 2009 in south-eastern Australia. We found growth rates of these two spec...

The evolution, morphology and development of fern leaves

Directory of Open Access Journals (Sweden)

Alejandra eVasco

2013-09-01

Full Text Available Leaves are lateral determinate structures formed in a predictable sequence (phyllotaxy on the flanks of an indeterminate shoot apical meristem. The origin and evolution of leaves in vascular plants has been widely debated. Being the main conspicuous organ of nearl all vascular plants and often easy to recognize as such, it seems surprising that leaves have had multiple origins. For decades, morphologists, anatomists, paleobotanists, and systematists have contributed data to this debate. More recently, molecular genetic studies have provided insight into leaf evolution and development mainly within angiosperms and, to a lesser extent, lycophytes. There has been recent interest in extending leaf evolutionary developmental studies to other species and lineages, particularly in lycophytes and ferns. Therefore, a review of fern leaf morphology, evolution and development is timely. Here we discuss the theories of leaf evolution in ferns, morphology and diversity of fern leaves, and experimental results of fern leaf development. We summarize what is known about the molecular genetics of fern leaf development and what future studies might tell us about the evolution of fern leaf development.

Fluxes of oxidised and reduced nitrogen above a mixed coniferous forest exposed to various nitrogen emission sources

International Nuclear Information System (INIS)

Neirynck, J.; Kowalski, A.S.; Carrara, A.; Genouw, G.; Berghmans, P.; Ceulemans, R.

2007-01-01

Concentrations of nitrogen gases (NH 3 , NO 2 , NO, HONO and HNO 3 ) and particles (pNH 4 and pNO 3 ) were measured over a mixed coniferous forest impacted by high nitrogen loads. Nitrogen dioxide (NO 2 ) represented the main nitrogen form, followed by nitric oxide (NO) and ammonia (NH 3 ). A combination of gradient method (NH 3 and NO x ) and resistance modelling techniques (HNO 3 , HONO, pNH 4 and pNO 3 ) was used to calculate dry deposition of nitrogen compounds. Net flux of NH 3 amounted to -64 ng N m -2 s -1 over the measuring period. Net fluxes of NO x were upward (8.5 ng N m -2 s -1 ) with highest emission in the morning. Fluxes of other gases or aerosols substantially contributed to dry deposition. Total nitrogen deposition was estimated at -48 kg N ha -1 yr -1 and consisted for almost 80% of NH x . Comparison of throughfall nitrogen with total deposition suggested substantial uptake of reduced N (±15 kg N ha -1 yr -1 ) within the canopy. - Reduced nitrogen was found to be the main contributor to total deposition which was predominantly governed by dry deposition

Chloroplast genome evolution in early diverged leptosporangiate ferns.

Science.gov (United States)

Kim, Hyoung Tae; Chung, Myong Gi; Kim, Ki-Joong

2014-05-01

In this study, the chloroplast (cp) genome sequences from three early diverged leptosporangiate ferns were completed and analyzed in order to understand the evolution of the genome of the fern lineages. The complete cp genome sequence of Osmunda cinnamomea (Osmundales) was 142,812 base pairs (bp). The cp genome structure was similar to that of eusporangiate ferns. The gene/intron losses that frequently occurred in the cp genome of leptosporangiate ferns were not found in the cp genome of O. cinnamomea. In addition, putative RNA editing sites in the cp genome were rare in O. cinnamomea, even though the sites were frequently predicted to be present in leptosporangiate ferns. The complete cp genome sequence of Diplopterygium glaucum (Gleicheniales) was 151,007 bp and has a 9.7 kb inversion between the trnL-CAA and trnVGCA genes when compared to O. cinnamomea. Several repeated sequences were detected around the inversion break points. The complete cp genome sequence of Lygodium japonicum (Schizaeales) was 157,142 bp and a deletion of the rpoC1 intron was detected. This intron loss was shared by all of the studied species of the genus Lygodium. The GC contents and the effective numbers of codons (ENCs) in ferns varied significantly when compared to seed plants. The ENC values of the early diverged leptosporangiate ferns showed intermediate levels between eusporangiate and core leptosporangiate ferns. However, our phylogenetic tree based on all of the cp gene sequences clearly indicated that the cp genome similarity between O. cinnamomea (Osmundales) and eusporangiate ferns are symplesiomorphies, rather than synapomorphies. Therefore, our data is in agreement with the view that Osmundales is a distinct early diverged lineage in the leptosporangiate ferns.

Modelling three-dimensional distribution of photosynthetically active radiation in sloping coniferous stands

International Nuclear Information System (INIS)

Knyazikhin, Yu.; Kranigk, J.; Miessen, G.; Panfyorov, O.; Vygodskaya, N.; Gravenhorst, G.

1996-01-01

Solar irradiance is a major environmental factor governing biological and physiological processes in a vegetation canopy. Solar radiation distribution in a canopy and its effect are three-dimensional in nature. However, most of the radiation models up to now have been one-dimensional. They can be successfully applied to large-scale studies of forest functioning. The one-dimensional modelling technique, however, does not provide adequate interpretation of small scale processes leading to forest growth. In this article we discuss a modelling strategy for the simulation of three-dimensional radiation distribution in a vegetation canopy of a small area (about 0.25–0.3 ha). We demonstrate its realisation to predict the three-dimensional radiative regime of phytosynthetically active radiation in a real coniferous stand located on hilly surroundings. Our model can be used to investigate the influence of different climatic conditions, forest management methods and field sites on the solar energy available for forest growth in small heterogeneous areas. Further, a three-dimensional process-oriented model helps to derive global variables affecting bio-physiological processes in a vegetation canopy shifting from small scale studies of the functioning of forests to regional, continental, and global scale problems. (author)

Chloroplast Genome Evolution in Early Diverged Leptosporangiate Ferns

OpenAIRE

Kim, Hyoung Tae; Chung, Myong Gi; Kim, Ki-Joong

2014-01-01

In this study, the chloroplast (cp) genome sequences from three early diverged leptosporangiate ferns were completed and analyzed in order to understand the evolution of the genome of the fern lineages. The complete cp genome sequence of Osmunda cinnamomea (Osmundales) was 142,812 base pairs (bp). The cp genome structure was similar to that of eusporangiate ferns. The gene/intron losses that frequently occurred in the cp genome of leptosporangiate ferns were not found in the cp genome of O. c...

Non-timber forest products in Hawaii

Science.gov (United States)

Katie Kamelamela; James B. Friday; Tamara Ticktin; Ashley. Lehman

2015-01-01

Hawaiian forests provide a wide array of non-timber forest products for both traditional and modern uses. Flowers, vines, and ferns are collected for creating garlands or lei for hula dances and parades. Lei made from materials gathered in the forest are made for personal use and sold, especially during graduation times. Bamboo is harvested for structures and for...

Using EO-1 Hyperion to Simulate HyspIRI Products for a Coniferous Forest: The Fraction of PAR Absorbed by Chlorophyll (fAPAR(sub chl)) and Leaf Water Content (LWC)

Science.gov (United States)

Zhang, Qingyuan; Middleton, Elizabeth M.; Gao, Bo-Cai; Cheng, Yen-Ben

2011-01-01

This study presents development of prototype products for terrestrial ecosystems in preparation for the future imaging spectrometer planned for the Hyperspectral Infrared Imager (HyspIRI) mission. We present a successful demonstration example in a coniferous forest of two product prototypes: fraction of photosynthetic active radiation (PAR) absorbed by chlorophyll of a canopy (fAPAR(sub chl)) and leaf water content (LWC), for future HyspIRI implementation at 60 m spatial resolution. For this, we used existing 30 m resolution imaging spectrometer data available from the Earth Observing One (EO-1) Hyperion satellite to simulate and prototype the level one radiometrically corrected radiance (L1R) images expected from the HyspIRI visible through shortwave infrared spectrometer. The HyspIRI-like images were atmospherically corrected to obtain surface reflectance, and spectrally resampled to produce 60 m reflectance images for wavelength regions that were comparable to all seven of the MODerate resolution Imaging Spectroradiometer (MODIS) land bands. Thus, we developed MODIS-like surface reflectance in seven spectral bands at the HyspIRI-like spatial scale, which was utilized to derive fAPARchl and LWC with a coupled canopy-leaf radiative transfer model (PROSAIL2) for the coniferous forest[1]. With this study, we provide additional evidence that the fAPARchl product is more realistic for describing the physiologically active canopy than the traditional fAPAR parameter for the whole canopy (fAPAR(sub canopy)), and thus should replace it in ecosystem process models to reduce uncertainties in terrestrial carbon cycle studies and ecosystem studies.

Use of 15N-labelled nitrogen deposition to quantify the source of nitrogen in runoff at a coniferous-forested catchment at Gardsjoen, Sweden

International Nuclear Information System (INIS)

Kjonaas, O. Janne; Wright, Richard F.

2007-01-01

To determine the source of dissolved inorganic nitrogen (N) in runoff, approx. 35 kg N enriched with the stable isotope 15 N (2110 per mille δ 15 N) was added to a mature coniferous forested catchment for one whole year. The total N input was approx. 50 kg ha -1 year -1 . The enrichment study was part of a long-term whole-catchment ammonium nitrate addition experiment at Gardsjoen, Sweden. The 15 N concentrations in precipitation, throughfall, runoff and upper forest floor were measured prior to, during, and 3-9 years following the 15 N addition. During the year of the 15 N addition the δ 15 N level in runoff largely reflected the level in incoming N, indicating that the leached NO 3 - came predominantly from precipitation. Only 1.1% of the incoming N was lost during the year of the tracer addition. The cumulative loss of tracer N over a 10-year period was only 3.9% as DIN and 1.1% as DON. - 15 N tracer addition showed that initially the main source of NO 3 - in runoff was N from atmospheric deposition

A molecular phylogeny of scaly tree ferns (Cyatheaceae).

Science.gov (United States)

Korall, Petra; Conant, David S; Metzgar, Jordan S; Schneider, Harald; Pryer, Kathleen M

2007-05-01

Tree ferns recently were identified as the closest sister group to the hyperdiverse clade of ferns, the polypods. Although most of the 600 species of tree ferns are arborescent, the group encompasses a wide range of morphological variability, from diminutive members to the giant scaly tree ferns, Cyatheaceae. This well-known family comprises most of the tree fern diversity (∼500 species) and is widespread in tropical, subtropical, and south temperate regions of the world. Here we investigate the phylogenetic relationships of scaly tree ferns based on DNA sequence data from five plastid regions (rbcL, rbcL-accD IGS, rbcL-atpB IGS, trnG-trnR, and trnL-trnF). A basal dichotomy resolves Sphaeropteris as sister to all other taxa and scale features support these two clades: Sphaeropteris has conform scales, whereas all other taxa have marginate scales. The marginate-scaled clade consists of a basal trichotomy, with the three groups here termed (1) Cyathea (including Cnemidaria, Hymenophyllopsis, Trichipteris), (2) Alsophila sensu stricto, and (3) Gymnosphaera (previously recognized as a section within Alsophila) + A. capensis. Scaly tree ferns display a wide range of indusial structures, and although indusium shape is homoplastic it does contain useful phylogenetic information that supports some of the larger clades recognised.

Climate change moisture stresses on northern coniferous forests

International Nuclear Information System (INIS)

Wein, R.W.; Hogg, E.H.

1990-01-01

The predictions of general circulation models suggest major climatic changes for high latitude tundra ecosystems and lower latitude forested ecosystems. Of particular interest to Canadians is the predicted shift in the boreal forest climate northward, with a considerable northern expansion of the grasslands of western Canada. Reductions in soil moisture would have both direct and indirect effects on forest composition and productivity. The most important likely physical factors subject to alteration are permafrost, hydrological regimes and fire. Under warmer and drier conditions, potential fire burn frequency will increase, and might lead to greater proportions of jack pine than previously present. It is anticipated that permafrost will disappear from the extensive discontinuous permafrost zone where soil permafrost temperatures are presently -3 degree C or higher. In wet sites, melting of the permafrost could lead to drowning of forests as soils subside and become temporarily waterlogged. In more northerly areas, forest growth may increase in drier areas as the depth of the active layer increases. Fire may be a significant feed-back mechanism that could enhance the greenhouse effect. The estimated proportion of carbon in Canadian peatlands is in the order of 170 gigatonnes, whereas one-tenth of a gigatonne of carbon is released annually by fossil fuel combustion in Canada. 11 refs

Effect of habitat preference on frond life span in three Cyathea tree ferns

Science.gov (United States)

Chiu, Tzu Yun; Wang, Hsiang Hua; Lun Kuo, Yao; Kume, Tomonori

2013-04-01

It has been reported that plants living in various geographical areas had different physiological forms, as factors of microenvironment have strong impacts on physiological characters. However, the physiological characters of fronds have been scarcely reported in ferns. In this study, we investigated physiological differences in response to the habitat preference in the three tree ferns in northeast Taiwan, Cyathea lepifera, C. spinulosa, and C. podophylla, prefer to open site, edge of forest, and interior forest, respectively. The canopy openness above the individuals of C. lepifera, C. spinulosa and C. podophylla were 29.2 ± 14.10 , 7.0 ± 3.07 and 5.0 ± 2.24 %, respectively. Among three species, C. podophylla had the longest frond life span (13.0 ± 4.12 months) than the two others (C. lepifera (6.8 ± 1.29 months) and C. spinulosa (7.3 ±1.35 months). Our result supported the general patterns that shade intolerant species have a shorter leaf life span than shade tolerant species. The maximum net CO2 assimilation of C. lepifera, C. spinulosa and C. podophylla were 11.46 ± 1.34, 8.27 ± 0.69, and 6.34 ± 0.54 μmol CO2 m-2 s-1, respectively. As well, C. lepifera had the highest photosynthetic light saturation point (LSP), while C. podophylla had the lowest LSP among these three tree ferns. These suggested that C. lepifera could be more efficient for capturing and utilizing light resources under the larger canopy openness condition than the other two species. We also found that frond C : N ratio were positively correlated with frond life span among species. C. podophylla, with the longest frond life span, had the highest frond C : N ratio (22.17 ± 1.95), which was followed by C. spinulosa (18.58 ± 1.37) and C. lepifera (18.68 ± 2.63) with shorter frond life span. The results were consistent to the theory that the fronds and leaves of shade intolerant species have high photosynthetic abilities with low C : N ratio. Key words: Canopy openness, frond life span

Forest type effects on the retention of radiocesium in organic layers of forest ecosystems affected by the Fukushima nuclear accident

Science.gov (United States)

Koarashi, Jun; Atarashi-Andoh, Mariko; Matsunaga, Takeshi; Sanada, Yukihisa

2016-12-01

The Fukushima Daiichi nuclear power plant disaster caused serious radiocesium (137Cs) contamination of forest ecosystems over a wide area. Forest-floor organic layers play a key role in controlling the overall bioavailability of 137Cs in forest ecosystems; however, there is still an insufficient understanding of how forest types influence the retention capability of 137Cs in organic layers in Japanese forest ecosystems. Here we conducted plot-scale investigations on the retention of 137Cs in organic layers at two contrasting forest sites in Fukushima. In a deciduous broad-leaved forest, approximately 80% of the deposited 137Cs migrated to mineral soil located below the organic layers within two years after the accident, with an ecological half-life of approximately one year. Conversely, in an evergreen coniferous forest, more than half of the deposited 137Cs remained in the organic layers, with an ecological half-life of 2.1 years. The observed retention behavior can be well explained by the tree phenology and accumulation of 137Cs associated with litter materials with different degrees of degradation in the organic layers. Spatial and temporal patterns of gamma-ray dose rates depended on the retention capability. Our results demonstrate that enhanced radiation risks last longer in evergreen coniferous forests than in deciduous broad-leaved forests.

Western forests and air pollution

International Nuclear Information System (INIS)

Olson, R.K.; Binkley, D.; Boehm, M.

1992-01-01

The book addresses the relationships between air pollution in the western United States and trends in the growth and condition of Western coniferous forests. The major atmospheric pollutants to which forest in the region are exposed are sulfur and nitrogen compounds and ozone. The potential effects of atmospheric pollution on these forests include foliar injury, alteration of growth rates and patterns, soil acidification, shifts in species composition, and modification of the effects of natural stresses

Duration of fuels reduction following prescribed fire in coniferous forests of U.S. national parks in California and the Colorado Plateau

Science.gov (United States)

van Mantgem, Phillip J.; Lalemand, Laura; Keifer, MaryBeth; Kane, Jeffrey M.

2016-01-01

Prescribed fire is a widely used forest management tool, yet the long-term effectiveness of prescribed fire in reducing fuels and fire hazards in many vegetation types is not well documented. We assessed the magnitude and duration of reductions in surface fuels and modeled fire hazards in coniferous forests across nine U.S. national parks in California and the Colorado Plateau. We used observations from a prescribed fire effects monitoring program that feature standard forest and surface fuels inventories conducted pre-fire, immediately following an initial (first-entry) prescribed fire and at varying intervals up to >20 years post-fire. A subset of these plots was subjected to prescribed fire again (second-entry) with continued monitoring. Prescribed fire effects were highly variable among plots, but we found on average first-entry fires resulted in a significant post-fire reduction in surface fuels, with litter and duff fuels not returning to pre-fire levels over the length of our observations. Fine and coarse woody fuels often took a decade or longer to return to pre-fire levels. For second-entry fires we found continued fuels reductions, without strong evidence of fuel loads returning to levels observed immediately prior to second-entry fire. Following both first- and second-entry fire there were increases in estimated canopy base heights, along with reductions in estimated canopy bulk density and modeled flame lengths. We did not find evidence of return to pre-fire conditions during our observation intervals for these measures of fire hazard. Our results show that prescribed fire can be a valuable tool to reduce fire hazards and, depending on forest conditions and the measurement used, reductions in fire hazard can last for decades. Second-entry prescribed fire appeared to reinforce the reduction in fuels and fire hazard from first-entry fires.

Transfer equations for cesium-137 for coniferous forest understorey plant species

International Nuclear Information System (INIS)

Wirth, E.; Hiersche, L.; Kammerer, L.; Krajewska, G.; Krestel, R.; Mahler, S.; Roemmelt, R.

1994-01-01

The transfer of cesium-137 from organic soil horizons to understorey vegetation has been studied on two coniferous tree sites. In total, 14 different plants preferably taking up their nutrients from organic soil layers were taken into account. A relatively good correlation was found to exist between the transfer factor (Bq/kg plant dry wt./Bq/kg O-horizons dry wt.) for dicotyledons (r=0.51) and berry plants (r=0.63), but there was no correlation for monocotyledons (r= 0 .15). The correlations could not be improved by additionally taking potassium in plant and soil into account. These results are discussed in respect to different parameters influencing the amount of cesium-137 uptake, including plants supported by mycorrhizal fungi

Mixed Conifer Forest Duff Consumption during Prescribed Fires: Tree Crown Impacts

NARCIS (Netherlands)

Hille, M.G.; Stephens, S.L.

2005-01-01

Fire suppression has produced large forest floor fuel loads in many coniferous forests in western North America. This study describes spatial patterns of duff consumption in a mixed-conifer forest in the north-central Sierra Nevada, California. Overstory crown coverage was correlated to spatial

Two new fern chloroplasts and decelerated evolution linked to the long generation time in tree ferns.

Science.gov (United States)

Zhong, Bojian; Fong, Richard; Collins, Lesley J; McLenachan, Patricia A; Penny, David

2014-04-30

We report the chloroplast genomes of a tree fern (Dicksonia squarrosa) and a "fern ally" (Tmesipteris elongata), and show that the phylogeny of early land plants is basically as expected, and the estimates of divergence time are largely unaffected after removing the fastest evolving sites. The tree fern shows the major reduction in the rate of evolution, and there has been a major slowdown in the rate of mutation in both families of tree ferns. We suggest that this is related to a generation time effect; if there is a long time period between generations, then this is probably incompatible with a high mutation rate because otherwise nearly every propagule would probably have several lethal mutations. This effect will be especially strong in organisms that have large numbers of cell divisions between generations. This shows the necessity of going beyond phylogeny and integrating its study with other properties of organisms. © The Author(s) 2014. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Large-scale phylogenomic analysis resolves a backbone phylogeny in ferns

Science.gov (United States)

Shen, Hui; Jin, Dongmei; Shu, Jiang-Ping; Zhou, Xi-Le; Lei, Ming; Wei, Ran; Shang, Hui; Wei, Hong-Jin; Zhang, Rui; Liu, Li; Gu, Yu-Feng; Zhang, Xian-Chun; Yan, Yue-Hong

2018-01-01

Abstract Background Ferns, originated about 360 million years ago, are the sister group of seed plants. Despite the remarkable progress in our understanding of fern phylogeny, with conflicting molecular evidence and different morphological interpretations, relationships among major fern lineages remain controversial. Results With the aim to obtain a robust fern phylogeny, we carried out a large-scale phylogenomic analysis using high-quality transcriptome sequencing data, which covered 69 fern species from 38 families and 11 orders. Both coalescent-based and concatenation-based methods were applied to both nucleotide and amino acid sequences in species tree estimation. The resulting topologies are largely congruent with each other, except for the placement of Angiopteris fokiensis, Cheiropleuria bicuspis, Diplaziopsis brunoniana, Matteuccia struthiopteris, Elaphoglossum mcclurei, and Tectaria subpedata. Conclusions Our result confirmed that Equisetales is sister to the rest of ferns, and Dennstaedtiaceae is sister to eupolypods. Moreover, our result strongly supported some relationships different from the current view of fern phylogeny, including that Marattiaceae may be sister to the monophyletic clade of Psilotaceae and Ophioglossaceae; that Gleicheniaceae and Hymenophyllaceae form a monophyletic clade sister to Dipteridaceae; and that Aspleniaceae is sister to the rest of the groups in eupolypods II. These results were interpreted with morphological traits, especially sporangia characters, and a new evolutionary route of sporangial annulus in ferns was suggested. This backbone phylogeny in ferns sets a foundation for further studies in biology and evolution in ferns, and therefore in plants. PMID:29186447

Large-scale phylogenomic analysis resolves a backbone phylogeny in ferns.

Science.gov (United States)

Shen, Hui; Jin, Dongmei; Shu, Jiang-Ping; Zhou, Xi-Le; Lei, Ming; Wei, Ran; Shang, Hui; Wei, Hong-Jin; Zhang, Rui; Liu, Li; Gu, Yu-Feng; Zhang, Xian-Chun; Yan, Yue-Hong

2018-02-01

Ferns, originated about 360 million years ago, are the sister group of seed plants. Despite the remarkable progress in our understanding of fern phylogeny, with conflicting molecular evidence and different morphological interpretations, relationships among major fern lineages remain controversial. With the aim to obtain a robust fern phylogeny, we carried out a large-scale phylogenomic analysis using high-quality transcriptome sequencing data, which covered 69 fern species from 38 families and 11 orders. Both coalescent-based and concatenation-based methods were applied to both nucleotide and amino acid sequences in species tree estimation. The resulting topologies are largely congruent with each other, except for the placement of Angiopteris fokiensis, Cheiropleuria bicuspis, Diplaziopsis brunoniana, Matteuccia struthiopteris, Elaphoglossum mcclurei, and Tectaria subpedata. Our result confirmed that Equisetales is sister to the rest of ferns, and Dennstaedtiaceae is sister to eupolypods. Moreover, our result strongly supported some relationships different from the current view of fern phylogeny, including that Marattiaceae may be sister to the monophyletic clade of Psilotaceae and Ophioglossaceae; that Gleicheniaceae and Hymenophyllaceae form a monophyletic clade sister to Dipteridaceae; and that Aspleniaceae is sister to the rest of the groups in eupolypods II. These results were interpreted with morphological traits, especially sporangia characters, and a new evolutionary route of sporangial annulus in ferns was suggested. This backbone phylogeny in ferns sets a foundation for further studies in biology and evolution in ferns, and therefore in plants. © The Authors 2017. Published by Oxford University Press.

How early ferns became trees.

Science.gov (United States)

Galtier, J; Hueber, F M

2001-09-22

A new anatomically preserved fern, discovered from the basalmost Carboniferous of Australia, shows a unique combination of very primitive anatomical characters (solid centrarch cauline protostele) with the elaboration of an original model of the arborescent habit. This plant possessed a false trunk composed of a repetitive branching system of very small stems, which established it as the oldest tree-fern known to date. The potential of this primitive zygopterid fern to produce such an unusual growth form-without real equivalent among living plants-is related to the possession of two kinds of roots that have complementary functional roles: (i) large roots produced by stems with immediate positive geotropism, strongly adapted to mechanical support and water uptake from the soil; and (ii) small roots borne either on large roots or on petiole bases for absorbing humidity inside the false trunk.

Spatial and Temporal Variabilities of Solar and Longwave Radiation Fluxes below a Coniferous Forest in the French Alps

Science.gov (United States)

Sicart, J. E.; Ramseyer, V.; Lejeune, Y.; Essery, R.; Webster, C.; Rutter, N.

2017-12-01

At high altitudes and latitudes, snow has a large influence on hydrological processes. Large fractions of these regions are covered by forests, which have a strong influence on snow accumulation and melting processes. Trees absorb a large part of the incoming shortwave radiation and this heat load is mostly dissipated as longwave radiation. Trees shelter the snow surface from wind, so sub-canopy snowmelt depends mainly on the radiative fluxes: vegetation attenuates the transmission of shortwave radiation but enhances longwave irradiance to the surface. An array of 13 pyranometers and 11 pyrgeometers was deployed on the snow surface below a coniferous forest at the CEN-MeteoFrance Col de Porte station in the French Alps (1325 m asl) during the 2017 winter in order to investigate spatial and temporal variabilities of solar and infrared irradiances in different meteorological conditions. Sky view factors measured with hemispherical photographs at each radiometer location were in a narrow range from 0.2 to 0.3. The temperature of the vegetation was measured with IR thermocouples and an IR camera. In clear sky conditions, the attenuation of solar radiation by the canopy reached 96% and its spatial variability exceeded 100 W m-2. Longwave irradiance varied by 30 W m-2 from dense canopy to gap areas. In overcast conditions, the spatial variabilities of solar and infrared irradiances were reduced and remained closely related to the sky view factor. A simple radiative model taking into account the penetration through the canopy of the direct and diffuse solar radiation, and isotropic infrared emission of the vegetation as a blackbody emitter, accurately reproduced the dynamics of the radiation fluxes at the snow surface. Model results show that solar transmissivity of the canopy in overcast conditions is an excellent proxy of the sky view factor and the emitting temperature of the vegetation remained close to the air temperature in this typically dense Alpine forest.

Comparative seasonal variations of spectral signatures of broad-leaved and coniferous stands from Landsat data. Comparison with other perennial environments

International Nuclear Information System (INIS)

Chaume, R.; Combeau, A.

1984-01-01

Spectral signatures of two distinct forest test areas were identified from digital data including 15 LANDSAT scenes covering the same geographical area: a broad-leaved forest (oak and beech) and a coniferous forest (scotch pine). Seasonal variations of the signatures were examined and were expressed in terms of various data: date, solar height and phenological state of vegetation cover. Results were compared to these obtained from other perennial surface conditions (grassland, bare soils) . Range of the seasonal variations of radiance is noted, as well as evolutionary peculiarities on each band and between themes. Rationing of spectral bands (particularly MSS 5 and 7) and their variation with time are specified [fr

ESTIMATION OF CARBON SEQUESTRATION BY RUSSIAN FORESTS: GEOSPATIAL ISSUE

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N. V. Malysheva

2017-01-01

Full Text Available Сategories of carbon sequestration assessment for Russian forests are identified by GIS toolkit. Those are uniform by bioclimatic and site-specific conditions strata corresponding to modern version of bioclimatic forest district division. Stratification of forests at early stage substantially reduces the ambiguity of the evaluation because phytomass conversion sequestration capacity and expansion factor dependent on site-specific condition for calculating of forest carbon sink are absolutely necessary. Forest management units were linked to strata. Biomass conversion and expansion factor for forest carbon sink assessment linked to the strata were recalculated for forest management units. All operations were carried out with GIS analytical toolkit due to accessible functionalities. Units for forest carbon storage inventory and forest carbon balance calculation were localized. Production capacity parameters and forest carbon sequestration capacity have been visualized on maps complied by ArcGIS. Based on spatially-explicit information, we have found out that the greatest annual rates of forest’s carbon accumulation in Russian forests fall into mixed coniferous-deciduous forests of European-Ural part of Russia to Kaliningrad, Smolensk and Briansk Regions, coniferous-deciduous forests close to the boundary of Khabarovsk Region and Primorskij Kray in the Far East, as well as separate forest management units of Kabardino-Balkariya NorthCaucasian mountain area. The geospatial visualization of carbon sequestration by Russian forests and carbon balance assessment has been given.

Towards resolving the complete fern tree of life.

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Lehtonen, Samuli

2011-01-01

In the past two decades, molecular systematic studies have revolutionized our understanding of the evolutionary history of ferns. The availability of large molecular data sets together with efficient computer algorithms, now enables us to reconstruct evolutionary histories with previously unseen completeness. Here, the most comprehensive fern phylogeny to date, representing over one-fifth of the extant global fern diversity, is inferred based on four plastid genes. Parsimony and maximum-likelihood analyses provided a mostly congruent results and in general supported the prevailing view on the higher-level fern systematics. At a deep phylogenetic level, the position of horsetails depended on the optimality criteria chosen, with horsetails positioned as the sister group either of Marattiopsida-Polypodiopsida clade or of the Polypodiopsida. The analyses demonstrate the power of using a 'supermatrix' approach to resolve large-scale phylogenies and reveal questionable taxonomies. These results provide a valuable background for future research on fern systematics, ecology, biogeography and other evolutionary studies.

Towards resolving the complete fern tree of life.

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Samuli Lehtonen

Full Text Available In the past two decades, molecular systematic studies have revolutionized our understanding of the evolutionary history of ferns. The availability of large molecular data sets together with efficient computer algorithms, now enables us to reconstruct evolutionary histories with previously unseen completeness. Here, the most comprehensive fern phylogeny to date, representing over one-fifth of the extant global fern diversity, is inferred based on four plastid genes. Parsimony and maximum-likelihood analyses provided a mostly congruent results and in general supported the prevailing view on the higher-level fern systematics. At a deep phylogenetic level, the position of horsetails depended on the optimality criteria chosen, with horsetails positioned as the sister group either of Marattiopsida-Polypodiopsida clade or of the Polypodiopsida. The analyses demonstrate the power of using a 'supermatrix' approach to resolve large-scale phylogenies and reveal questionable taxonomies. These results provide a valuable background for future research on fern systematics, ecology, biogeography and other evolutionary studies.

The influence of coniferous canopies on understorey vegetation and soils in mountain forests of the northern Calcareous Alps

International Nuclear Information System (INIS)

Ewald, Joerg

2000-01-01

Compositional and edaphic gradients were studied in montane forests of the Bavarian Alps (Germany), in which natural mixed deciduous-coniferous tree layers have been altered by past management in favour of Picea abies. Data on species composition and ecological factors were collected in a stratified random sample of 84 quadrats comprising a gradient from pure Picea to pure Fagus sylvatica stands. Data about the understorey composition were subjected to indirect (DCA) and direct gradient analysis (RDA) with the proportion of Picea in the canopy as a constraining variable. Three principal components of a matrix containing seven descriptors of mineral soil, relief and tree layer cover were included as covariables describing the variability of primary ecological factors. Gradients of organic topsoil morphology and chemistry were extracted correspondingly. Responses of individual species, species group and topsoil attributes were studied by simple and partial correlation analysis. Mosses were significantly more abundant and diverse under Picea stands. Few graminoid and herb species were partially associated with Picea, and total understorey richness and cover did not differ systematically by stand type. No relationship between tree layer and understorey diversity was detected at the studied scale. Juvenile Fagus sylvatica was the only woody species significantly less abundant under Picea. In the topsoil lower base saturation, lower pH and larger C/N ratios in the litter layer were partially attributable to the proportion of Picea, only for base saturation a relationship was detected in greater soil depth also. The frequency of broad humus form types did not differ by tree species, nor was overall depth of organic forest floor attributable to canopy composition

The role of forest type on throughfall during extreme precipitation events - A comparison of methods using data from the Pohorje mountains (NE Slovenia)

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Vilhar, Urša; Simončič, Primož

2013-04-01

Extreme precipitation in the Alpine region is a major environmental factor due to high frequency of such events and consequences such as flooding of populated valley floors, erosion, avalanches, debris flow and landslides endangering exposed settlements. However, the effects of extreme precipitation are buffered by forest cover, therefore forest management practices should aim towards decreased surface runoff and soil erosion in alpine climates. In Central Europe, many pure Norway spruce stands, established on primary beech sites, were converted into mixed stands over the last 60 years. The conversion of forest management from spruce monocultures into mixed deciduous-coniferous forests changed the forest structure dramatically. This changes could influence the hydrological processes on the catchment scale, associated with major river flooding following extreme precipitation events. In this study, the effect of forest management on the partitioning of rainfall into throughfall and stemflow in coniferous and mixed deciduous-coniferous stands on Pohorje mountains in NE Slovenia were investigated. Four spruce Picea abies (L. Karst) stands were compared to four mixed spruce-beech Fagus sylvatica (L.) stands with prevailing forest plant community Cardamine Savensi Fagetum with small areas of Sphagno - Piceetum, Bazzanio - Piceetum and Rhytidiodelpholorei - Piceetum intermixed. The monthly throughfall from rain collectors and half-hourly throughfall from automated rain gauges in growing seasons from 2008 till 2012 were analyzed in order to estimate the throughfall under forest canopies. In the mixed spruce-beech stands the monthly stemflow on beech trees was also measured. For the precipitation in the open an automated weather station and rainfall collectors in an open area located very close to the research plots were used. There were small differences in seasonal throughfall found between the coniferous and mixed deciduous-coniferous stands. The seasonal throughfall was

The effect of different growth regimes on the endophytic bacterial communities of the fern, Dicksonia sellowiana hook (Dicksoniaceae

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Irene de Araújo Barros

2010-12-01

Full Text Available Endophytic bacteria associated with the fern Dicksonia sellowiana were investigated. The bacterial communities from the surface-sterilized pinnae and rachis segments of the plants from the Brazilian Atlantic Rainforest that grew in native field conditions were compared with the bacterial communities from plants grown in greenhouses and plants that were initially grown in greenhouses and then transferred to the forest. From 540 pinnae and 540 rachis segments, 163 (30.2% and 346 (64.2% were colonized by bacteria, respectively. The main bacterial genera and species that were isolated included Bacillus spp. (B. cereus, B. megaterium, B. pumilus and B. subtilis, Paenibacillus sp., Amphibacillus sp., Gracilibacillus sp., Micrococcus sp. and Stenotrophomonas spp. (S. maltophilia and S. nitroreducens. B. pumilus was the most frequently isolated bacterial species. Amphibacillus and Gracilibacillus were reported as endophytes for the first time. Other commonly found bacterial genera were not observed in D. sellowiana, which may reflect preferences of specific bacterial communities inside this fern or detection limitations due to the isolation procedures. Plants that were grown in greenhouses and plants that were reintroduced into the forest displayed more bacterial genera and species diversity than native field plants, suggesting that reintroduction shifts the bacterial diversity. Endophytic bacteria that displayed antagonistic properties against different microorganisms were detected, but no obvious correlation was found between their frequencies with plant tissues or with plants from different growth regimes. This paper reports the first isolation of endophytic bacteria from a fern.

The effect of different growth regimes on the endophytic bacterial communities of the fern, Dicksonia sellowiana hook (Dicksoniaceae).

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de Araújo Barros, Irene; Luiz Araújo, Welington; Lúcio Azevedo, João

2010-10-01

Endophytic bacteria associated with the fern Dicksonia sellowiana were investigated. The bacterial communities from the surface-sterilized pinnae and rachis segments of the plants from the Brazilian Atlantic Rainforest that grew in native field conditions were compared with the bacterial communities from plants grown in greenhouses and plants that were initially grown in greenhouses and then transferred to the forest. From 540 pinnae and 540 rachis segments, 163 (30.2%) and 346 (64.2%) were colonized by bacteria, respectively. The main bacterial genera and species that were isolated included Bacillus spp. ( B. cereus, B. megaterium, B. pumilus and B. subtilis ) , Paenibacillus sp. , Amphibacillus sp. , Gracilibacillus sp. , Micrococcus sp. and Stenotrophomonas spp. ( S. maltophilia and S. nitroreducens ). B. pumilus was the most frequently isolated bacterial species . Amphibacillus and Gracilibacillus were reported as endophytes for the first time. Other commonly found bacterial genera were not observed in D. sellowiana , which may reflect preferences of specific bacterial communities inside this fern or detection limitations due to the isolation procedures. Plants that were grown in greenhouses and plants that were reintroduced into the forest displayed more bacterial genera and species diversity than native field plants, suggesting that reintroduction shifts the bacterial diversity. Endophytic bacteria that displayed antagonistic properties against different microorganisms were detected, but no obvious correlation was found between their frequencies with plant tissues or with plants from different growth regimes. This paper reports the first isolation of endophytic bacteria from a fern.

Remote detection of canopy water stress in coniferous forests using the NS001 Thematic Mapper Simulator and the thermal infrared multispectral scanner

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Pierce, Lars L.; Running, Steven W.; Riggs, George A.

1990-01-01

Water stress was induced in two coniferous forest stands in West Germany by severing tree sapwood. Leaf water potential, Psi(L), measurements indicated that maximum, naturally occurring levels of water stress developed in the stressed plots while control plots exhibited natural diurnal trends. Images of each site were obtained with the Thematic Mapper Simulator (NS001) and the Thermal Infrared Multispectral Scanner (TIMS) 12 to 15 days after stress induction. NS001 bands 2 to 6, NS001 indices combining bands 4 and 6, and NS001 and TIMS thermal bands showed significant radiance differences between stressed and control plots when large differences in Psi(L) and relative water content (RWC) existed during the morning overflights at Munich. However, the NS001 and TIMS sensors could not detect the slightly smaller differences in Psi(L) and RWC during the Munich afternoon and Frankfurt overflights. The results suggest that routine detection of canopy water stress under operational conditions is difficult utilizing current sensor technology.

Organelle Genome Inheritance in Deparia Ferns (Athyriaceae, Aspleniineae, Polypodiales

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Li-Yaung Kuo

2018-04-01

Full Text Available Organelle genomes of land plants are predominately inherited maternally but in some cases can also be transmitted paternally or biparentally. Compared to seed plants (>83% genera of angiosperms and >12% genera of gymnosperms, plastid genome (plastome inheritance has only been investigated in fewer than 2% of fern genera, and mitochondrial genome (mitogenome from only one fern genus. We developed a new and efficient method to examine plastome and mitogenome inheritance in a fern species—Deparia lancea (Athyriaceae, Aspleniineae, Polypodiales, and found that plastid and mitochondrial DNAs were transmitted from only the maternal parentage to a next generation. To further examine whether both organelle genomes have the same manner of inheritance in other Deparia ferns, we sequenced both plastid and mitochondrial DNA regions of inter-species hybrids, and performed phylogenetic analyses to identify the origins of organellar DNA. Evidence from our experiments and phylogenetic analyses support that both organelle genomes in Deparia are uniparentally and maternally inherited. Most importantly, our study provides the first report of mitogenome inheritance in eupolypod ferns, and the second one among all ferns.

Soil and vegetation changes after clear-felling coniferous forests: effects of varying removal of logging residues

International Nuclear Information System (INIS)

Olsson, Bengt.

1995-01-01

Effects of the intensity of logging residue harvesting on soil nutrient status and ground vegetation cover were examined over a 16-year period in two series of field experiments in Sweden. Short-term effects of slash harvesting and stump removal on soil water chemistry were studied after clear-felling a Norway spruce (Picea abies (L.) Karst.) stand in SW Sweden. Soil water concentrations of NH4 + , and NO 3 - and K + were lower shortly after whole-tree harvesting (i.e. stem and slash harvesting) than shortly after conventional stem-only harvesting or complete tree harvesting (i.e. stem, slash and stump removal). However, 5 years later there were no longer differences in nutrient concentrations detected between treatments, and nutrient levels approached those normally found in drainage water from forest land. Similar studies focussed on long-term (16 years) effects were conducted on four coniferous forest sites in Sweden, two in north and the other two in the south. In each region one site was situated in a pure Scots pine stand (Pinus sylvestris L.) and the other in a pure Norway spruce stand. In general, the intensity of slash harvesting had no effect on the total pools of nitrogen or carbon in the soil. Furthermore, this study showed experimentally that the harvesting of logging residues results in long-term soil acidification and depletions of exchangeable base cations, manganese and zinc pools, which lead in turn to a reduction in base saturation levels. A major implication for practical forestry was that guidelines and recommendations concerning the large-scale utilization of logging residues should be based more on the nutritional and soil acidifying consequences of this practice than on its potential effect on soil organic matter storage. It would also be possible to mitigate the detrimental effects that slash harvesting has on site conditions by applying wood-ash or other nutrients in inorganic form. 53 refs, 4 figs, 4 tabs

Soil and vegetation changes after clear-felling coniferous forests: effects of varying removal of logging residues

Energy Technology Data Exchange (ETDEWEB)

Olsson, Bengt

1995-11-01

Effects of the intensity of logging residue harvesting on soil nutrient status and ground vegetation cover were examined over a 16-year period in two series of field experiments in Sweden. Short-term effects of slash harvesting and stump removal on soil water chemistry were studied after clear-felling a Norway spruce (Picea abies (L.) Karst.) stand in SW Sweden. Soil water concentrations of NH4{sup +}, and NO{sub 3}{sup -} and K{sup +} were lower shortly after whole-tree harvesting (i.e. stem and slash harvesting) than shortly after conventional stem-only harvesting or complete tree harvesting (i.e. stem, slash and stump removal). However, 5 years later there were no longer differences in nutrient concentrations detected between treatments, and nutrient levels approached those normally found in drainage water from forest land. Similar studies focussed on long-term (16 years) effects were conducted on four coniferous forest sites in Sweden, two in north and the other two in the south. In each region one site was situated in a pure Scots pine stand (Pinus sylvestris L.) and the other in a pure Norway spruce stand. In general, the intensity of slash harvesting had no effect on the total pools of nitrogen or carbon in the soil. Furthermore, this study showed experimentally that the harvesting of logging residues results in long-term soil acidification and depletions of exchangeable base cations, manganese and zinc pools, which lead in turn to a reduction in base saturation levels. A major implication for practical forestry was that guidelines and recommendations concerning the large-scale utilization of logging residues should be based more on the nutritional and soil acidifying consequences of this practice than on its potential effect on soil organic matter storage. It would also be possible to mitigate the detrimental effects that slash harvesting has on site conditions by applying wood-ash or other nutrients in inorganic form. 53 refs, 4 figs, 4 tabs

Sensitivity of three tree ferns during their first phase of life to the variation of solar radiation and water availability in a Mexican cloud forest.

Science.gov (United States)

Riaño, Karolina; Briones, Oscar

2015-09-01

Regeneration niche differentiation promotes species coexistence and diversity; however, the ecological implications for the initial life phases of the majority of pteridophytes are unknown. We analyzed the sensitivity of gametophytes and juvenile sporophytes of the tree ferns Alsophila firma, Cyathea divergens, and Lophosoria quadripinnata to variation in light and water availability. We evaluated gametophyte desiccation tolerance using saturated salt solutions and gametophyte solar radiation tolerance by direct exposure. We also transplanted juvenile sporophytes in environments with 7% and 23% canopy openness and two watering levels. The response of photosynthetic efficiency and water content suggest that the gametophytes of the three species require high relative humidity, tolerate direct solar radiation for up to 30 min and that the response is not species-dependent. Sporophyte size and gas exchange were greater in the more open site, but decreased watering had a lesser effect on these variables in the more closed site. Relative growth rate correlated with the net assimilation rate and leaf weight ratio. Juvenile sporophytes of A. firma were more shade tolerant, while those of C. divergens and L. quadripinnata acclimatized to both environments. Specialization to humid habitats in the tree fern gametophyte restricts the species to humid forests, while differences in the plasticity of the sporophyte facilitate coexistence of the species. © 2015 Botanical Society of America.

Small scale temporal distribution of radiocesium in undisturbed coniferous forest soil: Radiocesium depth distribution profiles.

Science.gov (United States)

Teramage, Mengistu T; Onda, Yuichi; Kato, Hiroaki

2016-04-01

The depth distribution of pre-Fukushima and Fukushima-derived (137)Cs in undisturbed coniferous forest soil was investigated at four sampling dates from nine months to 18 months after the Fukushima nuclear power plant accident. The migration rate and short-term temporal variability among the sampling profiles were evaluated. Taking the time elapsed since the peak deposition of pre-Fukushima (137)Cs and the median depth of the peaks, its downward displacement rates ranged from 0.15 to 0.67 mm yr(-1) with a mean of 0.46 ± 0.25 mm yr(-1). On the other hand, in each examined profile considerable amount of the Fukushima-derived (137)Cs was found in the organic layer (51%-92%). At this moment, the effect of time-distance on the downward distribution of Fukushima-derived (137)Cs seems invisible as its large portion is still found in layers where organic matter is maximal. This indicates that organic matter seems the primary and preferential sorbent of radiocesium that could be associated with the physical blockage of the exchanging sites by organic-rich dusts that act as a buffer against downward propagation of radiocesium, implying radiocesium to be remained in the root zone for considerable time period. As a result, this soil section can be a potential source of radiation dose largely due to high radiocesium concentration coupled with its low density. Generally, such kind of information will be useful to establish a dynamic safety-focused decision support system to ease and assist management actions. Copyright © 2016 Elsevier Ltd. All rights reserved.

Bulgarian Rila mountain forest ecosystems study site: site description and SO42-, NO3- deposition

Science.gov (United States)

Karl Zeller; Christo Bojinov; Evgeny Donev; Nedialko Nikolov

1998-01-01

Bulgaria's forest ecosystems (31 percent of the country's area) are considered vulnerable to dry and wet pollution deposition. Coniferous forests that cover one-third of the total forest land are particularly sensitive to pollution loads. The USDA Forest Service, Sofia University, and the Bulgarian Forest Research Institute (FRI) established a cooperative...

Forest as Underground-Closed Dendrocenoecosystem

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S. N. Sannikov

2014-02-01

Full Text Available As a result of quantitative «microecosystem» analysis of structural and functional relationships between biogeocenosis components in coniferous forests, the leading role of stand-edificator's root competition factor has been identified in determining the undergrowth and lower layer plant’s growth, compared with its «light» competition. Considering the dominant role of a tree stand root competition in the formation of other forest biogeocenosis components, new definition of «forest» as «underground-closed dendrocenoecosystem» have been proposed.

Fluxes of oxidised and reduced nitrogen above a mixed coniferous forest exposed to various nitrogen emission sources

Energy Technology Data Exchange (ETDEWEB)

Neirynck, J. [Research Institute for Nature and Forest, Gaverstraat 4, B-9500 Geraardsbergen (Belgium)]. E-mail: johan.neirynck@inbo.be; Kowalski, A.S. [Departamento de Fisica Aplicida, Facultad de Ciencias, Universidad de Granada, Calle Fuentenueva, SP-18071 Granada (Spain); Carrara, A. [Fundacion CEAM, Parque Technologico, Calle Charles H. Darwin 14, SP-46980 Paterna (Valencia) (Spain); Genouw, G. [Research Institute for Nature and Forest, Gaverstraat 4, B-9500 Geraardsbergen (Belgium); Berghmans, P. [Flemish Institute for Technological Research, Boeretang 200, B-2400 Mol (Belgium); Ceulemans, R. [Department of Biology, University of Antwerp, Universiteitsplein 1, B-2610 Wilrijk (Antwerp) (Belgium)

2007-09-15

Concentrations of nitrogen gases (NH{sub 3}, NO{sub 2}, NO, HONO and HNO{sub 3}) and particles (pNH{sub 4} and pNO{sub 3}) were measured over a mixed coniferous forest impacted by high nitrogen loads. Nitrogen dioxide (NO{sub 2}) represented the main nitrogen form, followed by nitric oxide (NO) and ammonia (NH{sub 3}). A combination of gradient method (NH{sub 3} and NO {sub x} ) and resistance modelling techniques (HNO{sub 3}, HONO, pNH{sub 4} and pNO{sub 3}) was used to calculate dry deposition of nitrogen compounds. Net flux of NH{sub 3} amounted to -64 ng N m{sup -2} s{sup -1} over the measuring period. Net fluxes of NO {sub x} were upward (8.5 ng N m{sup -2} s{sup -1}) with highest emission in the morning. Fluxes of other gases or aerosols substantially contributed to dry deposition. Total nitrogen deposition was estimated at -48 kg N ha{sup -1} yr{sup -1} and consisted for almost 80% of NH {sub x} . Comparison of throughfall nitrogen with total deposition suggested substantial uptake of reduced N ({+-}15 kg N ha{sup -1} yr{sup -1}) within the canopy. - Reduced nitrogen was found to be the main contributor to total deposition which was predominantly governed by dry deposition.

Monitoring coniferous forest biomass change using a Landsat trajectory-based approach

Science.gov (United States)

Magdalena Main-Knorn; Warren B. Cohen; Robert E. Kennedy; Wojciech Grodzki; Dirk Pflugmacher; Patrick Griffiths; Patrick Hostert

2013-01-01

Forest biomass is a major store of carbon and thus plays an important role in the regional and global carbon cycle. Accurate forest carbon sequestration assessment requires estimation of both forest biomass and forest biomass dynamics over time. Forest dynamics are characterized by disturbances and recovery, key processes affecting site productivity and the forest...

An ant-plant by-product mutualism is robust to selective logging of rain forest and conversion to oil palm plantation.

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Fayle, Tom M; Edwards, David P; Foster, William A; Yusah, Kalsum M; Turner, Edgar C

2015-06-01

Anthropogenic disturbance and the spread of non-native species disrupt natural communities, but also create novel interactions between species. By-product mutualisms, in which benefits accrue as side effects of partner behaviour or morphology, are often non-specific and hence may persist in novel ecosystems. We tested this hypothesis for a two-way by-product mutualism between epiphytic ferns and their ant inhabitants in the Bornean rain forest, in which ants gain housing in root-masses while ferns gain protection from herbivores. Specifically, we assessed how the specificity (overlap between fern and ground-dwelling ants) and the benefits of this interaction are altered by selective logging and conversion to an oil palm plantation habitat. We found that despite the high turnover of ant species, ant protection against herbivores persisted in modified habitats. However, in ferns growing in the oil palm plantation, ant occupancy, abundance and species richness declined, potentially due to the harsher microclimate. The specificity of the fern-ant interactions was also lower in the oil palm plantation habitat than in the forest habitats. We found no correlations between colony size and fern size in modified habitats, and hence no evidence for partner fidelity feedbacks, in which ants are incentivised to protect fern hosts. Per species, non-native ant species in the oil palm plantation habitat (18 % of occurrences) were as important as native ones in terms of fern protection and contributed to an increase in ant abundance and species richness with fern size. We conclude that this by-product mutualism persists in logged forest and oil palm plantation habitats, with no detectable shift in partner benefits. Such persistence of generalist interactions in novel ecosystems may be important for driving ecosystem functioning.

Quantifying the missing link between forest albedo and productivity in the boreal zone

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Hovi, Aarne; Liang, Jingjing; Korhonen, Lauri; Kobayashi, Hideki; Rautiainen, Miina

2016-11-01

Albedo and fraction of absorbed photosynthetically active radiation (FAPAR) determine the shortwave radiation balance and productivity of forests. Currently, the physical link between forest albedo and productivity is poorly understood, yet it is crucial for designing optimal forest management strategies for mitigating climate change. We investigated the relationships between boreal forest structure, albedo and FAPAR using a radiative transfer model called Forest Reflectance and Transmittance model FRT and extensive forest inventory data sets ranging from southern boreal forests to the northern tree line in Finland and Alaska (N = 1086 plots). The forests in the study areas vary widely in structure, species composition, and human interference, from intensively managed in Finland to natural growth in Alaska. We show that FAPAR of tree canopies (FAPARCAN) and albedo are tightly linked in boreal coniferous forests, but the relationship is weaker if the forest has broadleaved admixture, or if canopies have low leaf area and the composition of forest floor varies. Furthermore, the functional shape of the relationship between albedo and FAPARCAN depends on the angular distribution of incoming solar irradiance. We also show that forest floor can contribute to over 50 % of albedo or total ecosystem FAPAR. Based on our simulations, forest albedos can vary notably across the biome. Because of larger proportions of broadleaved trees, the studied plots in Alaska had higher albedo (0.141-0.184) than those in Finland (0.136-0.171) even though the albedo of pure coniferous forests was lower in Alaska. Our results reveal that variation in solar angle will need to be accounted for when evaluating climate effects of forest management in different latitudes. Furthermore, increasing the proportion of broadleaved trees in coniferous forests is the most important means of maximizing albedo without compromising productivity: based on our findings the potential of controlling forest

Conservation Priorities for Tree Ferns (Cyatheaceae in Sri Lanka

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R. H. G. Ranil

2011-09-01

Full Text Available Diversity, phytogeography and conservation status of Sri Lankan tree-ferns are discussed in this paper. The family Cyatheaceae is represented by eight taxa (seven species and one doubtful variety in Sri Lanka with a high rate of endemism of 75%. Apart from Cyathea walkerae and C. gigantea, the other species are restricted to geographically isolated areas in the country with limited population sizes. Fortunately, all Sri Lankan species of Cyathea occur within the protected areas of the wet zone. However, ex situ conservation is limited to C. walkerae and C. crinita at Botanic Gardens in Hakgala. Despite the family being listed in Annex II of CITES, its species have not yet been assessed in Sri Lanka for the Red Listing criteria. Identification of the nature and level of threat to Sri Lankan Cyathea species is therefore a major priority, followed by the monitoring of populations in situ in protected areas in the wet zone. Ex situ conservation of rare species and cultivation of Cyathea species from spores have also been identified as priority areas. A strong programme should be developed with the National Herbarium to explore little known forest patches in the wet zone to enhance our knowledge of Cyathea species in Sri Lanka. Such information will provide a strong basis for preparing a conservation and management plan for tree-ferns in the country.

[Simulation study on the effects of climate change on aboveground biomass of plantation in southern China: Taking Moshao forest farm in Huitong Ecological Station as an example].

Science.gov (United States)

Dai, Er Fu; Zhou, Heng; Wu, Zhuo; Wang, Xiao-Fan; Xi, Wei Min; Zhu, Jian Jia

2016-10-01

Global climate warming has significant effect on territorial ecosystem, especially on forest ecosystem. The increase in temperature and radiative forcing will significantly alter the structure and function of forest ecosystem. The southern plantation is an important part of forests in China, its response to climate change is getting more and more intense. In order to explore the responses of southern plantation to climate change under future climate scenarios and to reduce the losses that might be caused by climate change, we used climatic estimated data under three new emission scenarios, representative concentration pathways (RCPs) scenarios (RCP2.6 scenario, RCP4.5 scenario, and RCP8.5 scenario). We used the spatially dynamic forest landscape model LANDIS-2, coupled with a forest ecosystem process model PnET-2, to simulate the impact of climate change on aboveground net primary production (ANPP), species' establishment probability (SEP) and aboveground biomass of Moshao forest farm in Huitong Ecological Station, which located in Hunan Province during the period of 2014-2094. The results showed that there were obvious differences in SEP and ANPP among different forest types under changing climate. The degrees of response of SEP to climate change for different forest types were shown as: under RCP2.6 and RCP4.5, artificial coniferous forest>natural broadleaved forest>artificial broadleaved forest. Under RCP8.5, natural broadleaved forest>artificial broadleaved forest>artificial coniferous forest. The degrees of response of ANPP to climate change for different forest types were shown as: under RCP2.6, artificial broadleaved forest> natural broadleaved forest>artificial coniferous forest. Under RCP4.5 and RCP8.5, natural broadleaved forest>artificial broadleaved forest>artificial coniferous forest. The aboveground biomass of the artificial coniferous forest would decline at about 2050, but the natural broadleaved forest and artificial broadleaved forest showed a

Lianas, tree ferns and understory species: indicators of conservation status in the Brazilian Atlantic Rainforest remnants, southeastern Brazil.

Science.gov (United States)

Castello, A C D; Coelho, S; Cardoso-Leite, E

2017-01-01

Indicators are applied faster and at lower costs than conventional surveys, providing quick and efficient responses that can facilitate protected areas management. Our aim was to select indicators from vegetation to monitor protected areas. For this purpose, we analyzed understory and quantified lianas and tree ferns in protected and non-protected areas, in order to find indicator species. Our study areas are located in Vale do Ribeira, southeastern São Paulo state, Brazil. One of the areas is under two protection categories (IUCN's categories II and V), and the other is a privately owned farm. Lianas with large diameters (> 13 cm) and tree ferns with great heights (> 19 m) were considered indicators of undisturbed areas (protected areas) because their growth is directly related to forest successional stage. Indicator species within the protected area were shade tolerant species, such as Bathysa australis (A.St.-Hil.) K.Schum., whereas outside the protected area were pioneer species, such as Pera glabrata (Schott) Poepp. ex Baill. e Nectandra oppositifolia Ness. All of the suggested indicators can be used in management actions, especially in protected areas, to guarantee forest maintenance and ensure fulfillment of the conservation objectives of these areas.

Lianas, tree ferns and understory species: indicators of conservation status in the Brazilian Atlantic Rainforest remnants, southeastern Brazil

Directory of Open Access Journals (Sweden)

A. C. D. Castello

Full Text Available Abstract Indicators are applied faster and at lower costs than conventional surveys, providing quick and efficient responses that can facilitate protected areas management. Our aim was to select indicators from vegetation to monitor protected areas. For this purpose, we analyzed understory and quantified lianas and tree ferns in protected and non-protected areas, in order to find indicator species. Our study areas are located in Vale do Ribeira, southeastern São Paulo state, Brazil. One of the areas is under two protection categories (IUCN's categories II and V, and the other is a privately owned farm. Lianas with large diameters (> 13 cm and tree ferns with great heights (> 19 m were considered indicators of undisturbed areas (protected areas because their growth is directly related to forest successional stage. Indicator species within the protected area were shade tolerant species, such as Bathysa australis (A.St.-Hil. K.Schum., whereas outside the protected area were pioneer species, such as Pera glabrata (Schott Poepp. ex Baill. e Nectandra oppositifolia Ness. All of the suggested indicators can be used in management actions, especially in protected areas, to guarantee forest maintenance and ensure fulfillment of the conservation objectives of these areas.

Strong congruence in tree and fern community turnover in response to soils and climate in central Panama

DEFF Research Database (Denmark)

Jones, Mirkka; Ferrier, Simon; Condit, Richard

2013-01-01

1. Plant species turnover in central Panamanian forests has been principally attributed to the effects of dispersal limitation and a strong Caribbean to Pacific gradient in rainfall seasonality. Despite marked geological heterogeneity, the role of soil variation has not been rigorously examined. 2....... We modelled the compositional turnover of trees and ferns in the Panama Canal watershed as a function of soil chemistry, climate and geographical separation, using generalized dissimilarity models (GDMs). 3. Predictability in both plant groups was strong, with 74% of turnover explained in trees...... and 49% in ferns. Major trends in the two plant groups were strikingly similar. The independent effects of soils, and of climate for trees, were sizeable, but those of geographical distance were minor. In both plant groups, distance and climatic effects on species turnover covaried strongly. 4. Including...

Atmospheric deposition in coniferous and deciduous tree stands in Poland

Science.gov (United States)

Kowalska, Anna; Astel, Aleksander; Boczoń, Andrzej; Polkowska, Żaneta

2016-05-01

The objective of this study was to assess the transformation of precipitation in terms of quantity and chemical composition following contact with the crown layer in tree stands with varied species composition, to investigate the effect of four predominant forest-forming species (pine, spruce, beech, and oak) on the amount and composition of precipitation reaching forest soils, and to determine the sources of pollution in atmospheric precipitation in forest areas in Poland. The amount and chemical composition (pH, electric conductivity, alkalinity, and chloride, nitrate, sulfate, phosphate, ammonium, calcium, magnesium, sodium, potassium, iron aluminum, manganese, zinc, copper, total nitrogen, and dissolved organic carbon contents) of atmospheric (bulk, BP) and throughfall (TF) precipitation were studied from January to December 2010 on twelve forest monitoring plots representative of Polish conditions. The study results provided the basis for the determination of the fluxes of pollutants in the forest areas of Poland and allowed the comparison of such fluxes with values provided in the literature for European forest areas. The transformation of precipitation in the canopy was compared for different tree stands. The fluxes of substances in an open field and under canopy were influenced by the location of the plot, including the regional meteorological conditions (precipitation amounts), vicinity of the sea (effect of marine aerosols), and local level of anthropogenic pollution. Differences between the plots were higher in TF than in BP. The impact of the vegetation cover on the chemical composition of precipitation depended on the region of the country and dominant species in a given tree stand. Coniferous species tended to cause acidification of precipitation, whereas deciduous species increased the pH of TF. Pine and oak stands enriched precipitation with components that leached from the canopy (potassium, manganese, magnesium) to a higher degree than spruce and

THE ANTIMICROBIAL ACTIVITY OF SOME EXTRACTS OF FERN GAMETOPHYTES

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Ionica Deliu

2013-12-01

Full Text Available The nature freely offers us many resources for health and beauty. The ferns and their therapeutic properties are less exploit in Romania, except Lycopodium clavatum and Equisetum arvense. Some of the fern properties were demonstrated, like antioxidant, antimicrobial, antiviral, antihelmintic properties. Plants are reasonable alternative to synthetic drugs, avoid the side effect and high cost of synthetic drugs production. Also, the drug resistance bacteria can be controlled using plant derived remedies. In this study the antimicrobial effect of methanolic and ethanolic extracts from three fern species were tested. The extracts were gained from gametophytic stage of ferns obtained in vitro. The most obvious effect was observed for Asplenium trichomanes-ramosum extract. The total polyphenols and flavonoids content were established, too.

Experimental study of liquid evaporation rate from coniferous biomass

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Bulba E.E.

2017-01-01

Full Text Available The results of experimental studies of moisture evaporation from coniferous wood (spruce, pine are presented. The dependences of the mass evaporation rate on temperature and time are obtained. The calculation of the accommodation coefficient for the corresponding temperature ranges has been performed. The analysis of temperature regimes of drying of two typical coniferous wood species is carried out.

HS-SPME analysis of volatile organic compounds of coniferous needle litter

Science.gov (United States)

Isidorov, V. A.; Vinogorova, V. T.; Rafałowski, K.

The composition of volatile emission of Scots pine ( Pinus sylvestris) and spruce ( Picea exelsa) litter was studied by gas chromatography-mass spectrometry (GC-MS) and samples were collected by solid-phase microextraction (SPME) method. The list of identified compounds includes over 60 organic substances of different classes. It was established that volatile emission contain not only components of essential oils of pine and spruce needles but also a large number of organic compounds which are probably secondary metabolites of litter-decomposing fungi. They include lower carbonyl compounds and alcohols as well as products of terpene dehydration and oxidation. These data show that the processes of litter decomposition are an important source of reactive organic compounds under canopy of coniferous forests.

Spectroscopic Analysis of Arsenic Uptake in Pteris Ferns

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Terrence Slonecker

2009-09-01

Full Text Available Two arsenic-accumulating Pteris ferns (Pteris cretica mayii and Pteris multifida, along with a non-accumulating control fern (Nephrolepis exaltata were grown in greenhouse conditions in clean sand spiked with 0, 20, 50, 100 and 200 ppm sodium arsenate. Spectral data were collected for each of five replicates prior to harvest at 4-week intervals. Fern samples were analyzed for total metals content and Partial Least Squares and Stepwise Linear Regression techniques were used to develop models from the spectral data. Results showed that Pteris cretica mayii and Pteris multifida are confirmed hyperaccumulators of inorganic arsenic and that reasonably accurate predictive models of arsenic concentration can be developed from the first derivative of spectral reflectance of the hyperaccumulating Pteris ferns. Both the arsenic uptake and spectral results indicate that there is some species-specific variability but the results compare favorably with previously published data and additional research is recommended.

Detecting fragmentation extinction thresholds for forest understory plant species in peninsular Spain.

Science.gov (United States)

Rueda, Marta; Moreno Saiz, Juan Carlos; Morales-Castilla, Ignacio; Albuquerque, Fabio S; Ferrero, Mila; Rodríguez, Miguel Á

2015-01-01

Ecological theory predicts that fragmentation aggravates the effects of habitat loss, yet empirical results show mixed evidences, which fail to support the theory instead reinforcing the primary importance of habitat loss. Fragmentation hypotheses have received much attention due to their potential implications for biodiversity conservation, however, animal studies have traditionally been their main focus. Here we assess variation in species sensitivity to forest amount and fragmentation and evaluate if fragmentation is related to extinction thresholds in forest understory herbs and ferns. Our expectation was that forest herbs would be more sensitive to fragmentation than ferns due to their lower dispersal capabilities. Using forest cover percentage and the proportion of this percentage occurring in the largest patch within UTM cells of 10-km resolution covering Peninsular Spain, we partitioned the effects of forest amount versus fragmentation and applied logistic regression to model occurrences of 16 species. For nine models showing robustness according to a set of quality criteria we subsequently defined two empirical fragmentation scenarios, minimum and maximum, and quantified species' sensitivity to forest contraction with no fragmentation, and to fragmentation under constant forest cover. We finally assessed how the extinction threshold of each species (the habitat amount below which it cannot persist) varies under no and maximum fragmentation. Consistent with their preference for forest habitats probability occurrences of all species decreased as forest cover contracted. On average, herbs did not show significant sensitivity to fragmentation whereas ferns were favored. In line with theory, fragmentation yielded higher extinction thresholds for two species. For the remaining species, fragmentation had either positive or non-significant effects. We interpret these differences as reflecting species-specific traits and conclude that although forest amount is of

Detecting fragmentation extinction thresholds for forest understory plant species in peninsular Spain.

Directory of Open Access Journals (Sweden)

Marta Rueda

Full Text Available Ecological theory predicts that fragmentation aggravates the effects of habitat loss, yet empirical results show mixed evidences, which fail to support the theory instead reinforcing the primary importance of habitat loss. Fragmentation hypotheses have received much attention due to their potential implications for biodiversity conservation, however, animal studies have traditionally been their main focus. Here we assess variation in species sensitivity to forest amount and fragmentation and evaluate if fragmentation is related to extinction thresholds in forest understory herbs and ferns. Our expectation was that forest herbs would be more sensitive to fragmentation than ferns due to their lower dispersal capabilities. Using forest cover percentage and the proportion of this percentage occurring in the largest patch within UTM cells of 10-km resolution covering Peninsular Spain, we partitioned the effects of forest amount versus fragmentation and applied logistic regression to model occurrences of 16 species. For nine models showing robustness according to a set of quality criteria we subsequently defined two empirical fragmentation scenarios, minimum and maximum, and quantified species' sensitivity to forest contraction with no fragmentation, and to fragmentation under constant forest cover. We finally assessed how the extinction threshold of each species (the habitat amount below which it cannot persist varies under no and maximum fragmentation. Consistent with their preference for forest habitats probability occurrences of all species decreased as forest cover contracted. On average, herbs did not show significant sensitivity to fragmentation whereas ferns were favored. In line with theory, fragmentation yielded higher extinction thresholds for two species. For the remaining species, fragmentation had either positive or non-significant effects. We interpret these differences as reflecting species-specific traits and conclude that although

Soc stock in different forest-related land-uses in central Stara planina mountain, Bulgaria

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Zhiyanski Miglena

2009-01-01

Full Text Available Forest conversions may lead to an accumulation of carbon in vegetation, but little is known about changes in soil C storage with establishment of plantation forests. Understanding these effects is important to addressing issues relevant to ecosystem function and productivity, and to global balance of carbon. The study investigated the effects of the created coniferous plantations on former beech and pasture sites on the soil organic carbon storage. The major forest-related land-uses in the high mountainous regions of central Stara Planina Mountain were investigated: mountainous pasture, coniferous plantations (planted on previous pasture and beech forests between four and five decades ago and natural beech forests. The experimental data of soil properties, conducted in 2005, 2006 and 2007, were used in determining the variations in organic carbon storage in forest litter and in mineral soil under different land-use patterns. At each site five representative soil profiles were opened and described giving a total 75 soil samples from the soil layers respectively at 0-10, 10-30 and 30-50 cm depth. A total of 55 samples from forest floor layers (Aol, Aof, Aoh and greensward were collected with 25:25 cm plastic frame. The main soil properties were determined in accordance with the standardized methods in the Laboratory of soil science at the Forest Research Institute - BAS. The IPCC Good Practice Guidance for Land Use, Land Use Change and Forestry was used to estimate the soil organic carbon stock in soil and litter. The results obtained showed that the SOC stock was quite similar among forest land-uses. The conversion of natural beech forests to coniferous plantations in studied region is related with slightly expressed decrease in soil carbon storage. The values of SOC stocks in 0-50 cm soil layer in these sites were 8.5 (±2.1 tones/ha for pine and 11.0 (±1.4 tones/ha for spruce, while under the natural beech forest it was 14.8 (±1.0 tones

Distribution patterns of ferns and lycophytes in the Coastal Region of the state of Rio Grande do Sul, Brazil

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Felipe Gonzatti

2016-01-01

Full Text Available ABSTRACT A survey of ferns and lycophytes of the Coastal Region of the state of Rio Grande do Sul (CRRS was performed based on field work and collections of the main regional herbaria. The following were evaluated for each species: preferential habits (terrestrial, epiphytic or aquatic, geographic distribution patterns and habitats (forest, grassland, and wetland. The occurrence of a latitudinal gradient in diversity was tested over five latitudinal ranges using the Sørensen Similarity Index. A total of 17 lycophyte and 206 fern species representing 28 families was found between the latitudes of 29° and 34°S. Exclusively terrestrial species were predominant (162, with the majority (113 exhibiting wide Neotropical distributions, followed by species that also occurred in the state of Paraná (44. The forest habitat harbored the greatest number of species (159, while grasslands had the fewest (26. Cluster analysis showed pronounced floristic differentiation among latitudinal Ranges III (31°01' to 32°S and IV (32°01' to 31°S, with a similarity index of only 0.41. Our results demonstrate a strong north-to-south reduction in species richness in the study area, which is related to environmental conditions along the latitudinal gradient and, especially, microclimatic differences in the transition zone between the Atlantic Forest and Pampa biomes.

Leaf hydraulic capacity in ferns, conifers and angiosperms: impacts on photosynthetic maxima.

Science.gov (United States)

Brodribb, Tim J; Holbrook, N Michele; Zwieniecki, Maciej A; Palma, Beatriz

2005-03-01

* The hydraulic plumbing of vascular plant leaves varies considerably between major plant groups both in the spatial organization of veins, as well as their anatomical structure. * Five conifers, three ferns and 12 angiosperm trees were selected from tropical and temperate forests to investigate whether the profound differences in foliar morphology of these groups lead to correspondingly profound differences in leaf hydraulic efficiency. * We found that angiosperm leaves spanned a range of leaf hydraulic conductance from 3.9 to 36 mmol m2 s-1 MPa-1, whereas ferns (5.9-11.4 mmol m-2 s-1 MPa-1) and conifers (1.6-9.0 mmol m-2 s-1 MPa-1) were uniformly less conductive to liquid water. Leaf hydraulic conductance (Kleaf) correlated strongly with stomatal conductance indicating an internal leaf-level regulation of liquid and vapour conductances. Photosynthetic capacity also increased with Kleaf, however, it became saturated at values of Kleaf over 20 mmol m-2 s-1 MPa-1. * The data suggest that vessels in the leaves of the angiosperms studied provide them with the flexibility to produce highly conductive leaves with correspondingly high photosynthetic capacities relative to tracheid-bearing species.

Spatial and temporal trends in distribution of forest fires in Central and Eastern Europe

Science.gov (United States)

Ryszard Szczygieł; Barbara Ubysz; Tomasz. Zawiła-Niedźwiecki

2009-01-01

Forest in Central and Eastern Europe (CEE) covers 56,285,000 ha (5% of European total forested area). Forest cover in CEE makes 30% of land use. Almost 50% of the forest under study is formed by coniferous species and only 30% by deciduous ones. Forest younger than 60 years old grows on 57% of that area. These factors, together with climate conditions cause that on the...

Screening for ptaquiloside in ferns

DEFF Research Database (Denmark)

Rasmussen, Lars Holm; Pedersen, Henrik Ærenlund

2017-01-01

. Objective: To set-up a methodology for large-scale qualitative studies on the distribution of PTA in ferns using already available herbarium specimens as source. Methodology: PTA and the main degradation product pterosin B (PtB) were quantified in aqueous frond extracts by HPLC-DAD. PTA was quantified after...... of the analyte was obtained. Preservation of fronds in a plant press increase formation of PtB. Hence, the method is only suitable for qualitative studies. Presence of PTA and PtB were found in samples up to 50 years old. Among 21 ferns tested, the compounds were only found in Pteridium aquilinum. Conclusion...

Manganese in the litter fall-forest floor continuum of boreal and temperate pine and spruce forest ecosystems

DEFF Research Database (Denmark)

Berg, Björn; Erhagen, Björn; Johansson, Maj-Britt

2015-01-01

We have reviewed the literature on the role of manganese (Mn) in the litter fall-to-humus subsystem. Available data gives a focus on North European coniferous forests. Manganese concentrations in pine (Pinus spp.) foliar litter are highly variable both spatially and temporally within the same lit...

Detection probabilities of woodpecker nests in mixed conifer forests in Oregon

Science.gov (United States)

Robin E. Russell; Victoria A. Saab; Jay J. Rotella; Jonathan G. Dudley

2009-01-01

Accurate estimates of Black-backed (Picoides arcticus) and Hairy Woodpecker (P. villosus) nests and nest survival rates in post-fire landscapes provide land managers with information on the relative importance of burned forests to nesting woodpeckers. We conducted multiple-observer surveys in burned and unburned mixed coniferous forests in Oregon to identify important...

Morphology, Physiology, and Anatomy of Penny Fern (Drymoglossum phyloselloidesand Its Effect on Cocoa

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Fitria Yuliasmara

2013-08-01

Full Text Available This study aims to determine the anatomy, physiology and morphology of penny fern (Drimoglosum phylloseloides and its effect on cocoa. Morphological observation of penny fern used microscope to observe the roots, stems, leaves and spores. Physiology of penny fern was observed based on number of stomata and stomatal conductance using stomata printing method, while the amount of chlorophyll based on spectrophotometric method and rate of transpiration used cobalt chloride paper. Penny fern anatomy on cross-sectional and longitudinal in roots, stems and leaves. Penny fern growth was observed based the length of tendrils once a week during rainy and dry season. While the effect of penny fern invasion was observed based on variable leaf area with gravimetric method, the cross-section of attacked cacao branch using microtom and microscope and chlorophyll content by chlorophyll meter. Results showed that penny fern is a epiphytic weed which was crassulaceae acid metabolism plants that have the ability to absorb carbon dioxide at night and carry out photosynthesis during the day with closed stomata. Penny ferns reproduce using spores. The growth rate of penny fern 2.18 cm/week during the dry season and while in rainy season 3.89 cm/week. Penny fern leaf contains 0.0212 mg/g chlorophyll. Penny fern stomata density was 18.33/mm 2 with a width of opening stomata at night 26.3 µm which caused a veryslow rate of transpiration of 0.69 mm 2 /seconds. The existence penny fern on cocoa decreased leaf area and chlorophyll content decreased crop productivity which was indicated by decreasing in number of flowers, number of small, medium fruit, and large pods. However it had no effect on the number of leaves on one side flush cocoa. Key words: Drimoglosum phylloseloides, weeds, decrease productivity, Theobroma cacao

Survival and growth of epiphytic ferns depend on resource sharing

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Hua-Zheng eLu

2016-03-01

Full Text Available Locally available resources can be shared within clonal plant systems through physiological integration, thus enhancing their survival and growth. Most epiphytes exhibit clonal growth habit, but few studies have tested effects of physiological integration (resource sharing on survival and growth of epiphytes and whether such effects vary with species. We conducted two experiments, one on individuals (single ramets and another on groups (several ramets within a plot, with severed and intact rhizome treatments (without and with physiological integration on two dominant epiphytic ferns (Polypodiodes subamoena and Lepisorus scolopendrium in a subtropical montane moist forest in Southwest China. Rhizome severing (preventing integration significantly reduced ramet survival in the individual experiment and number of surviving ramets in the group experiment, and it also decreased biomass of both species in both experiments. However, the magnitude of such integration effects did not vary significantly between the two species. We conclude that resource sharing may be a general strategy for clonal epiphytes to adapt to forest canopies where resources are limited and heterogeneously distributed in space and time.

Random clustering ferns for multimodal object recognition

OpenAIRE

Villamizar Vergel, Michael Alejandro; Garrell Zulueta, Anais; Sanfeliu Cortés, Alberto; Moreno-Noguer, Francesc

2017-01-01

The final publication is available at link.springer.com We propose an efficient and robust method for the recognition of objects exhibiting multiple intra-class modes, where each one is associated with a particular object appearance. The proposed method, called random clustering ferns, combines synergically a single and real-time classifier, based on the boosted assembling of extremely randomized trees (ferns), with an unsupervised and probabilistic approach in order to recognize efficient...

Bird Perches Increase Forest Seeds on Puerto Rican Landslides.

Science.gov (United States)

Aaron B. Shiels; Lawrence R. Walker

2003-01-01

Landslides result in the loss of vertical vegetative structure, soil nutrients, and the soil seed bank. These losses impede timely recovery of tropical forest communities. In this study we added bird perches to six Puerto Rican landslides with three types of surfaces (bare, climbing fern, grass) in an effort to facilitate inputs of forest seeds through bird dispersal...

The evolutionary history of ferns inferred from 25 low-copy nuclear genes.

Science.gov (United States)

Rothfels, Carl J; Li, Fay-Wei; Sigel, Erin M; Huiet, Layne; Larsson, Anders; Burge, Dylan O; Ruhsam, Markus; Deyholos, Michael; Soltis, Douglas E; Stewart, C Neal; Shaw, Shane W; Pokorny, Lisa; Chen, Tao; dePamphilis, Claude; DeGironimo, Lisa; Chen, Li; Wei, Xiaofeng; Sun, Xiao; Korall, Petra; Stevenson, Dennis W; Graham, Sean W; Wong, Gane K-S; Pryer, Kathleen M

2015-07-01

• Understanding fern (monilophyte) phylogeny and its evolutionary timescale is critical for broad investigations of the evolution of land plants, and for providing the point of comparison necessary for studying the evolution of the fern sister group, seed plants. Molecular phylogenetic investigations have revolutionized our understanding of fern phylogeny, however, to date, these studies have relied almost exclusively on plastid data.• Here we take a curated phylogenomics approach to infer the first broad fern phylogeny from multiple nuclear loci, by combining broad taxon sampling (73 ferns and 12 outgroup species) with focused character sampling (25 loci comprising 35877 bp), along with rigorous alignment, orthology inference and model selection.• Our phylogeny corroborates some earlier inferences and provides novel insights; in particular, we find strong support for Equisetales as sister to the rest of ferns, Marattiales as sister to leptosporangiate ferns, and Dennstaedtiaceae as sister to the eupolypods. Our divergence-time analyses reveal that divergences among the extant fern orders all occurred prior to ∼200 MYA. Finally, our species-tree inferences are congruent with analyses of concatenated data, but generally with lower support. Those cases where species-tree support values are higher than expected involve relationships that have been supported by smaller plastid datasets, suggesting that deep coalescence may be reducing support from the concatenated nuclear data.• Our study demonstrates the utility of a curated phylogenomics approach to inferring fern phylogeny, and highlights the need to consider underlying data characteristics, along with data quantity, in phylogenetic studies. © 2015 Botanical Society of America, Inc.

Productivity and diversity of morel mushrooms in healthy, burned, and insect damaged forests of northeastern Oregon.

Science.gov (United States)

David Pilz; Nancy S. Weber; M. Carol Carter; Catherine G. Parks; Randy. Molina

2004-01-01

Large commercial crops of morels are harvested annually from montane coniferous forests of the Northwestern United States. Although some morels fruit annually in nondisturbed forests, others fruit copiously in areas experiencing fire, insect infestations, tree mortality, and soil disturbance. Many forest managers currently use thinning and prescribed fire to re-create...

Modeling impacts of fire severity on successional trajectories and future fire behavior in Alaskan boreal forests

Science.gov (United States)

Jill F. Johnstone; T. Scott Rupp; Mark Olson; David. Verbyla

2011-01-01

Much of the boreal forest in western North America and Alaska experiences frequent, stand-replacing wildfires. Secondary succession after fire initiates most forest stands and variations in fire characteristics can have strong effects on pathways of succession. Variations in surface fire severity that influence whether regenerating forests are dominated by coniferous...

Evolutionary and ecological perspectives of Late Paleozoic ferns. Part III. Anachoropterid ferns (including Anachoropteris, Tubicaulis, the Sermayaceae, Kaplanopteridaceae and Psalixochlaenaceae)

OpenAIRE

Galtier, Jean; Phillips, Tom L.

2014-01-01

The anachoropterid ferns, previously assigned to the family Anachoropteridaceae, are a group of anatomically preserved late Paleozoic filicalean ferns characterized by a C-shaped foliar xylem with abaxially recurved arms (inversicatenalean anatomy) and two main protoxylem strands. The variously curved to strongly inrolled foliar xylem certainly reflects different evolutionary trends within the morphogenus Anachoropteris. The occurrence of two groups of Tubicaulis is supported by differences i...

Effects of long-range transported pollutants on vegetation in boreal coniferous forests: Results from an five year investigation in the Solholmfjell area, Gjerstad, Aust-Agder; Effekter av langtransporterte luftforurensninger i boreal barskog: resultater av fem aars undersoekelser i Solhomfjell-omraadet, Gjerstad, Aust-Agder

Energy Technology Data Exchange (ETDEWEB)

Oekland, R H

1996-01-01

The conference paper relates to a project on investigating the effects of long-range transported pollutants in Norway. The paper gives a brief description of the more important results obtained in the project. The aim of the project was to investigate the pollution load in vegetation, soils and trees in Norwegian forest areas of the coniferous type. The project included the collection of samples from 200 test areas in a period of five years. 11 refs.

Native ectomycorrhizal fungi of limber and whitebark pine: Necessary for forest sustainability?

Science.gov (United States)

Cathy L. Cripps; Robert K. Antibus

2011-01-01

Ectomycorrhizal fungi are an important component of northern coniferous forests, including those of Pinus flexilis (limber pine) and P. albicaulis (whitebark pine) which are being decimated by white pine blister rust and mountain pine beetles. Ectomycorrhizal fungi are known to promote seedling establishment, tree health, and may play a role in forest sustainability....

Remote sensing of forest decline in the Czech Republic

Energy Technology Data Exchange (ETDEWEB)

Ardoe, J.

1998-04-01

This thesis describes the localization and quantification of deforestation and forest damage in Norway spruce forests in northern Czech Republic using Landsat data. Severe defoliation increases the spectral reflectance in all wavelength bands, especially in the mid infrared region. These spectral differences allow the separation of three damage categories with an accuracy of 75% using TM data and regression based relationships. Estimating the same categories using an artificial neural network, multi temporal TM data and topographic data yields slightly higher accuracy (78%). The methods are comparable when using identical input data, but the neural network more efficiently manage large input data sets without pre.processing, The estimated coniferous deforestation in northern Bohemia from 1972 to 1989 reveals especially affected areas between 600 and 1000 m.a.s.l. and on slopes facing south and southeast. The sector downwind a large source of sulphur dioxide was strongly deforested. Comparing regional forest damage statistics to three methods estimating harmful effects of sulphur dioxide on Norway spruce yielded significant relationships versus level of forest damage and accumulated salvage felling. Quantifying the effect of data uncertainties permit mapping the probabilities of areas to be significantly over or below thresholds for harmful effects on spruce forests. Satellite based estimation of coniferous forest health is a good complement to field surveys and aerial photography 137 refs, 7 figs, 2 tabs

Contributions of ectomycorrhizal fungal mats to forest soil respiration

Science.gov (United States)

C. Phillips; L.A. Kluber; J.P. Martin; B.A. Caldwell; B.J. Bond

2012-01-01

Distinct aggregations of fungal hyphae and rhizomorphs, or “mats”, formed by some genera of ectomycorrhizal (EcM) fungi are common features of soils in coniferous forests of the Pacific Northwest. We measured in situ respiration rates of Piloderma mats and neighboring non-mat soils in an old-growth Douglas-fir forest in western Oregon to investigate whether there was...

The omnipresent water fern

NARCIS (Netherlands)

Nierop, K.G.J.; Speelman, E.N.; de Leeuw, J.W.; Reichart, G.J.

2011-01-01

Several studies have reported the presence of large amounts of lignin in ubiquitously occurring species of the freshwater fern Azolla. Molecular analysis using flash pyrolysis and thermally assisted hydrolysis and methylation shows, however, that neither the leaves nor the roots of Azolla contain

Sources of nitrous oxide emitted from European forest soils

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P. Ambus

2006-01-01

Full Text Available Forest ecosystems may provide strong sources of nitrous oxide (N2O, which is important for atmospheric chemical and radiative properties. Nonetheless, our understanding of controls on forest N2O emissions is insufficient to narrow current flux estimates, which still are associated with great uncertainties. In this study, we have investigated the quantitative and qualitative relationships between N-cycling and N2O production in European forests in order to evaluate the importance of nitrification and denitrification for N2O production. Soil samples were collected in 11 different sites characterized by variable climatic regimes and forest types. Soil N-cycling and associated production of N2O was assessed following application of 15N-labeled nitrogen. The N2O emission varied significantly among the different forest soils, and was inversely correlated to the soil C:N ratio. The N2O emissions were significantly higher from the deciduous soils (13 ng N2O-N cm-3 d-1 than from the coniferous soils (4 ng N2O-N cm-3 d-1. Nitrate (NO3- was the dominant substrate for N2O with an average contribution of 62% and exceeding 50% at least once for all sites. The average contribution of ammonium (NH4+ to N2O averaged 34%. The N2O emissions were correlated with gross nitrification activities, and as for N2O, gross nitrification was also higher in deciduous soils (3.4 µg N cm-3 d-1 than in coniferous soils (1.1 µg N cm-3 d-1. The ratio between N2O production and gross nitrification averaged 0.67% (deciduous and 0.44% (coniferous. Our study suggests that changes in forest composition in response to land use activities and global change may have implications for regional budgets of greenhouse gases. From the study it also became clear that N2O emissions were driven by the nitrification activity, although the N2O was produced per se mainly from denitrification. Increased nitrification in response to accelerated N inputs predicted for forest ecosystems in Europe may

Increased topsoil carbon stock across China's forests.

Science.gov (United States)

Yang, Yuanhe; Li, Pin; Ding, Jinzhi; Zhao, Xia; Ma, Wenhong; Ji, Chengjun; Fang, Jingyun

2014-08-01

Biomass carbon accumulation in forest ecosystems is a widespread phenomenon at both regional and global scales. However, as coupled carbon-climate models predicted, a positive feedback could be triggered if accelerated soil carbon decomposition offsets enhanced vegetation growth under a warming climate. It is thus crucial to reveal whether and how soil carbon stock in forest ecosystems has changed over recent decades. However, large-scale changes in soil carbon stock across forest ecosystems have not yet been carefully examined at both regional and global scales, which have been widely perceived as a big bottleneck in untangling carbon-climate feedback. Using newly developed database and sophisticated data mining approach, here we evaluated temporal changes in topsoil carbon stock across major forest ecosystem in China and analysed potential drivers in soil carbon dynamics over broad geographical scale. Our results indicated that topsoil carbon stock increased significantly within all of five major forest types during the period of 1980s-2000s, with an overall rate of 20.0 g C m(-2) yr(-1) (95% confidence interval, 14.1-25.5). The magnitude of soil carbon accumulation across coniferous forests and coniferous/broadleaved mixed forests exhibited meaningful increases with both mean annual temperature and precipitation. Moreover, soil carbon dynamics across these forest ecosystems were positively associated with clay content, with a larger amount of SOC accumulation occurring in fine-textured soils. In contrast, changes in soil carbon stock across broadleaved forests were insensitive to either climatic or edaphic variables. Overall, these results suggest that soil carbon accumulation does not counteract vegetation carbon sequestration across China's forest ecosystems. The combination of soil carbon accumulation and vegetation carbon sequestration triggers a negative feedback to climate warming, rather than a positive feedback predicted by coupled carbon-climate models

El historiador Fernández de Piedrahita

Directory of Open Access Journals (Sweden)

Carlos López Narváez

1964-10-01

Full Text Available Varón de Dios, las letras y la patria, Lucas Fernández de Piedrahita nació en Santafé de Bogotá, el 6 de marzo de 1624, de hidalgo linaje por su padre español, y de principesca sangre materna, como que su progenitora, doña Catalina Collantes, esposa de don Domingo Fernández de Soto y Piedrahita, era nieta de doña Francisca Coya de la realeza inca del Perú.

Leaching of nitrate from temperate forests - effects of air pollution and forest management

DEFF Research Database (Denmark)

Gundersen, Per; Schmidt, Inger Kappel; Raulund-Rasmussen, Karsten

2006-01-01

deposition (> 8-10 kg ha(-1) a(-1)). We synthesized the current understanding of factors controlling N leaching in relation to three primary causes of N cycle disruption: (i) Increased N input (air pollution, fertilization, N-2 fixing plants). In European forests, elevated N deposition explains approximately...... half of the variability in N leaching, some of the remaining variability could be explained by differences in N availability or "N status". For coniferous forests, needle N content above 1.4% and (or) forest floor C:N ratio lower than 25 were thresholds for elevated nitrate leaching. At adjacent sites...... conifer forests receive higher N deposition and exhibit higher nitrate loss than deciduous forests; an exception is alder that shows substantial nitrate leaching through N fixation input. Fertilization with N poses limited risk to water quality, when applied to N-limited forests. (ii) Reduced plant uptake...

Unearthing Secrets of the Forest

Science.gov (United States)

Beldin, Sarah I.; Perakis, Steven S.

2009-01-01

Forests are a defining feature for large areas of the Pacific northwestern United States from northern California to Alaska. Coniferous temperate rainforests in the western Cascade and coastal mountain ranges are appreciated for their aesthetic value and abundant natural resources. Few people recognize the riches beneath the forest floor; yet, soil is a key ecosystem component that makes each type of forest unique. Soils harbor immense biological diversity and control the release of water and nutrients that support life above ground. Understanding how carbon and nutrients cycle in forests, known as forest biogeochemistry, is crucial for evaluating forest productivity, composition, diversity, and change. At the U.S. Geological Survey (USGS) Forest and Rangeland Ecosystem Science Center, research in the Terrestrial Ecosystems Laboratory focuses on nutrient cycling in five themes: climate change, nutrition and sustainability, fire effects, restoration, and forest-stream linkages. This research is essential to understand the entire forest ecosystem and to use the best science available to make informed policy and management decisions.

36 CFR 223.277 - Forest botanical products definition.

Science.gov (United States)

2010-07-01

..., boughs, bryophytes, bulbs, burls, cones, ferns, fungi (including mushrooms), forbs, grasses, mosses, nuts, pine straw, roots, sedges, seeds, shrubs, transplants, tree sap, and wildflowers. Forest botanical products are not animals, animal parts, Christmas trees, fence material, firewood, insects, mine props...

Long-term changes in soil pH across major forest ecosystems in China

Science.gov (United States)

Yang, Yuanhe; Li, Pin; He, Honglin; Zhao, Xia; Datta, Arindam; Ma, Wenhong; Zhang, Ying; Liu, Xuejun; Han, Wenxuan; Wilson, Maxwell C.; Fang, Jingyun

2015-02-01

Atmospheric acidic deposition has been a major environmental problem since the industrial revolution. However, our understanding of the effect of acidic deposition on soil pH is inconclusive. Here we examined temporal variations in topsoil pH and their relationships with atmospheric sulfur and nitrogen deposition across China's forests from the 1980s to the 2000s. To accomplish this goal, we conducted artificial neural network simulations using historical soil inventory data from the 1980s and a data set synthesized from literature published after 2000. Our results indicated that significant decreases in soil pH occurred in broadleaved forests, while minor changes were observed in coniferous and mixed coniferous and broadleaved forests. The magnitude of soil pH change was negatively correlated with atmospheric sulfur and nitrogen deposition. This relationship highlights the need for stringent measures that reduce sulfur and nitrogen emissions so as to maintain ecosystem structure and function.

Proyecto conservación, restauración y desarrollo de las islas Juan Fernández, Chile

OpenAIRE

CUEVAS, JAIME G.; VAN LEERSUM, GART

2001-01-01

From a scientific point of view, the Juan Fernández islands contain one of the most interesting floras of the planet. Although protected as a National Park and a World Biosphere Reserve, 400 years of human interference have left deep traces in the native plant communities. Repeated burning, overexploitation of species, and the introduction of animal and plant plagues have taken 75 % of the endemic vascular flora to the verge of extinction. In 1997, Chile's national forest service (Corporación...

Ultrasonic synthesis of fern-like ZnO nanoleaves and their enhanced photocatalytic activity

International Nuclear Information System (INIS)

Ma, Qing Lan; Xiong, Rui; Zhai, Bao-gai; Huang, Yuan Ming

2015-01-01

Graphical abstract: - Highlights: • Fern-like ZnO nanoleaves were synthesized by ultrasonicating Zn microcrystals in water. • A fern-like ZnO nanoleaf is a self-assembly of ZnO nanoplates along one ZnO nanorod. • Fern-like ZnO nanoleaves exhibit enhanced photocatalytic activity than ZnO nanocrystals. • The branched hierarchical structures are responsible for the enhanced photocatalytic activity. - Abstract: Two-dimensional fern-like ZnO nanoleaves were synthesized by ultrasonicating zinc microcrystals in water. The morphology, crystal structure, optical property and photocatalytic activity of the fern-like ZnO nanoleaves were characterized with scanning electron microscopy, X-ray diffraction, transmission electron microscopy, photoluminescence spectroscopy and ultraviolet–visible spectroscopy, respectively. It is found that one fern-like ZnO nanoleaf is composed of one ZnO nanorod as the central trunk and a number of ZnO nanoplates as the side branches in opposite pairs along the central ZnO nanorod. The central ZnO nanorod in the fern-like nanoleaves is about 1 μm long while the side-branching ZnO nanoplates are about 100 nm long and 20 nm wide. Further analysis has revealed that ZnO nanocrystals are the building blocks of the central ZnO nanorod and the side-branching ZnO nanoplates. Under identical conditions, fern-like ZnO nanoleaves exhibit higher photocatalytic activity in photodegrading methyl orange in aqueous solution than spherical ZnO nanocrystals. The first-order photocatalytic rate constant of the fern-like ZnO nanoleaves is about four times as large as that of the ZnO nanoparticles. The branched architecture of the hierarchical nanoleaves is suggested be responsible for the enhanced photocatalytic activity of the fern-like ZnO nanoleaves

The effect of different growth regimes on the endophytic bacterial communities of the fern, Dicksonia sellowiana hook (Dicksoniaceae)

OpenAIRE

Irene de Araújo Barros; Welington Luiz Araújo; João Lúcio Azevedo

2010-01-01

Endophytic bacteria associated with the fern Dicksonia sellowiana were investigated. The bacterial communities from the surface-sterilized pinnae and rachis segments of the plants from the Brazilian Atlantic Rainforest that grew in native field conditions were compared with the bacterial communities from plants grown in greenhouses and plants that were initially grown in greenhouses and then transferred to the forest. From 540 pinnae and 540 rachis segments, 163 (30.2%) and 346 (64.2%) were c...

The morphology of ferns

NARCIS (Netherlands)

Holttum, R.E.

1959-01-01

A fern plant consists of a stem, bearing leaves and roots. The leaves (or some of them) bear dehiscent sporangia, each sporangium containing unicellular spores, which are in most cases Wind-dispersed. A spore germinates to produce a small green plant called a prothallus. The Prothallus bears sexual

Distribution and dynamics of hayscented fern following stand harvest

Science.gov (United States)

Songlin Fei; Peter J. Gould; Melanie J. Kaeser; Kim C. Steiner

2008-01-01

The distribution and dynamics of hayscented fern were examined as part of a large-scale study of oak regeneration in Pennsylvania. The study included 69 stands covering 3,333 acres in two physiographic provinces. Hayscented fern was more widely distributed and occurred at higher densities in the Allegheny Plateau physiographic provinces versus the Ridge and Valley...

Radiation and water use efficiencies of two coniferous forest canopies

Science.gov (United States)

Lamaud, E.; Brunet, Y.; Berbigier, P.

1996-12-01

Two experiments were performed in a confierous forest (maritime pine) in the southwest of France, one in 1994 and the other in 1995. Two sites were chosen, differing by age, height and structure of the trees, as well as the nature of the understorey. In both cases measurements of turbulent fluxes were made at two levels above and within the forest canopy, using sonic anemometers and open-path infrared CO 2-H 2O analysers. The flux differences derived from the two measurement levels allowed the Radiation and Water Use Efficiencies (RUE and WUE, respectively) to be evaluated for both canopy crowns. The results are based on the analysis of about ten days from each experiment. For both campaigns RUE is significantly larger during cloudy conditions when the fraction of diffuse radiation ( {Q id}/{Q i}) increases. An empirical linear relation between RUE and {Q id}/{Q i} is established for each site, with a smaller intercept and a larger slope for the older forest. In clear conditions ( {Q id}/{Q i} < 0.4 ), RUE is about 30 % lower for this forest. Tree photosynthesis, estimated as the net CO 2 flux of the foliated layer F c, appears poorly correlated (r 2 < 0.4) with transpiration (net water vapour flux E). This is shown to result from strong variations in the atmospheric saturation deficit D during both campaigns. At both sites WUE turns out to be a hyperbolic function of D ( {Fc}/{E} = {-k}/{D}). The coefficient k is 50 % larger for the younger forest. This is in agreement with the values obtained for RUE, and indicates that photosynthetic rates decrease with the age of the trees.

Association of pteridophyte species in two fragments of Atlantic Coastal Forest in the Brazilian Northeast

Directory of Open Access Journals (Sweden)

Iva Carneiro Leão Barros

2006-09-01

Full Text Available This study aims to investigate fern flora similarity and fern species relationships in the study areas, in terms of their substrates, habitat types, and life forms. The study was conducted in the Água Azul forest fragment, municipality of Timbaúba, Pernambuco, and the Maria Maior forest fragment, municipality of São José da Laje, Alagoas. The Jaccard similarity index was used for cluster analysis. The 112 species that occur in the two areas were used for numerical analysis. The floristic similarity was great (J=43.75%, principally due to similarities in the two areas vegetational types, as was expected due to their geographic proximity to one another and their similar climatic conditions. Five groups of associated species were determined for the Água Azul fragment and six groups for the Maria Maior fragment. In general, the ecological factors that determined fern species associations were habitat and type of substrate.

Fern of the future?

NARCIS (Netherlands)

Brinkhuis, H.; Bijl, P.K.

Held in the palm of a human hand, a single specimen of Azolla filiculoides looks downright inconsequential. Even with the scaly leaves of this miniature aquatic fern spread flat, it barely spans the distance between the creases that cleave the flesh. Its fibrous root tendrils dangle like a lock of

Restoration of three forest herbs in the Liliaceae family by manipulating deer herbivory and overstorey and understorey vegetation

Science.gov (United States)

Cynthia D. Huebner; Kurt W. Gottschalk; Gary W. Miller; Patrick H. Brose

2010-01-01

Research on herbaceous vegetation restoration in forests characterised by overstorey tree harvests, excessive deer herbivory, and a dominant fern understorey is lacking. Most of the plant diversity found in Eastern hardwood forests in the United States is found in the herbaceous understorey layer. Loss of forest herbaceous species is an indicator of declining forest...

Effects of forest fires and post-fire rehabilitation: a Colorado, USA case study

Science.gov (United States)

Lee H. MacDonald; Isaac J. Larsen

2009-01-01

Anthropogenic activities have increased the number of large, high-burn severity wildfires in the lower and mid-elevation coniferous forests in Colorado as well as much of the western US. Forests provide most of the water for cities and agriculture, and the increased runoff and erosion after wildfires is a major concern because of the potential adverse effects on...

Asplenium bird’s nest ferns in rainforest canopies are climate-contingent refuges for frogs

Directory of Open Access Journals (Sweden)

Brett R. Scheffers

2014-12-01

Full Text Available Epiphytes are important for canopy dwelling organisms because they provide a cool and moist microhabitat in the relatively hot and dry canopy. Here we examine whether epiphytic Asplenium ferns act as important habitats for arboreal frogs. We conducted extensive fern and habitat surveys for frogs in the Philippines, and complimented these surveys with roaming day and night canopy surveys to identify the full extent of habitat use across the vertical strata. We artificially dried ferns of various sizes to identify relationships between water and temperature buffering. Ferns are the preferred diurnal microhabitat and breeding habitat for arboreal frogs. A strong positive relationship exists between fern size and frog usage and abundance. Our drying experiments show that large ferns buffer maximum temperatures and reduce variability in temperatures, and buffering is directly linked to their hydration. Frogs are likely using large ferns for their moist, cool, environments for breeding and daytime retreat, which supports the buffered microhabitat hypothesis—these plants promote species coexistence through habitat creation and amelioration of physical stress. However, drying experiments suggest that this buffering is contingent on regular rainfall. Altered rainfall regimes could lead to the unexpected loss of the functional capacity of these important fern habitats. Keywords: Climate change, Functionality, Microhabitat, Refuge, Ectotherm, Precipitation

New species of Malaysian ferns

NARCIS (Netherlands)

Holttum, R.E.

1962-01-01

The present paper includes descriptions of several new species of ferns found among recent collections from various parts of Malaysia; also two new combinations of names of species which are of interest on account of their taxonomic history.

RICHNESS AND FLORISTIC COMPOSITION OF THE FERN COMMUNITY IN RIPARIAN FOREST OF THE RIVER ‘CADEIA’, IN RIO GRANDE DO SUL STATE, BRAZIL

Directory of Open Access Journals (Sweden)

Ivanete Teresinha Mallmann

2014-03-01

Full Text Available http://dx.doi.org/10.5902/1980509813327The present study analyzed richness and specific composition of the fern community in fragments fromthe riparian forest of river ‘Cadeia’, under different levels of human impact, in Santa Maria do Herval, RioGrande do Sul state, Brazil. An amount of 120 sample units were delimited, equitably distributed in threefragments (FI, II and III in which all species were surveyed and the richness was recorded. The floristiccomposition among fragments was compared using Jaccard’s index and spatial distribution of units wasevaluated through multidimensional scaling. Richness data were presented in the form of rarefaction curvesbased on samples and non-parametric diversity estimators. A total of 40 species were found, belonging to13 families. The greater floristic similarity was between FI and FII. Sample units from FI formed the mostdefined grouping and they had more exclusive species than the others. The rarefaction curve for the totalsampling almost reached the asymptote and estimators indicated a maximum of 45 species, which meansthat the majority of species was surveyed at the study site. A decreasing gradient of mean richness per unitwas observed as the urbanization increased in the matrix habitat of the fragments. These results form a database to be used in management, conservation and reforestation measures in degraded riparian forests. Theycan be directly compared to results from other studies that used rarefaction and richness estimators, whichis not possible to do with many of the surveys accomplished in Brazil so far.

Tear ferning test in healthy dogs.

Science.gov (United States)

Oriá, Arianne P; Raposo, Ana Claudia S; Araújo, Nayone L L C; Lima, Felipe B; Masmali, Ali M

2017-11-07

To evaluate and compare three tear sampling methods using two grading scales for administering the tear ferning test (TFT) to healthy dogs. In total, 90 dogs (180 eyes) were subjected to tear sampling using millimetered strips, reused after the Schirmer tear test (STT) (Schirmer group, SG). Then, the dogs were subdivided into three groups according to sampling approach: micropipette (MPG), microcapillary (MCG), and Schirmer sample 2 (S2G). The collected tears were dried on a clean microscope glass slide at room temperature and humidity. The ferning patterns were observed under a polarized light microscope and classified according to the Rolando and Masmali grading scales. Although all three methods were feasible, the STT was easier to perform in clinical settings. Type I and Grade 1 were the most commonly observed (64.17% and 61.7%, respectively) regardless of collection method. There was no significant difference between the STT median values and the TFT classifications. The TFT is appropriate for dogs and can be performed using the three suggested sampling methods, with a higher frequency of Type I and Grade 1. Thus, it is possible to use both grading scales in the classification of tear ferning in dogs. © 2017 American College of Veterinary Ophthalmologists.

Radiation-induced cell death in embryogenic cells of coniferous plants

International Nuclear Information System (INIS)

Watanabe, Yoshito; Homma-Takeda, Shino; Yukawa, Masae; Nishimura, Yoshikazu; Sasamoto, Hamako; Takahagi, Masahiko

2004-01-01

Reproductive processes are particularly radiosensitive in plant development, which was clearly illustrated in reduction of seed formation in native coniferous plants around Chernobyl after the nuclear accident. For the purpose to investigate the effects of ionizing radiation on embryonic formation in coniferous plants, we used an embryo-derived embryogenic cell culture of a Japanese native coniferous plant, Japanese cedar (Cryplomeria japonica). The embryogenic cells were so radiosensitive that most of the cells died by X-ray irradiation of 5 Gy. This indicated that the embryogenic cells are as radiosensitive as some mammalian cells including lymphocytes. We considered that this type of radiosensitive cell death in the embryogenic cells should be responsible for reproductive damages of coniferous plants by low dose of ionizing radiation. The cell death of the embryogenic cells was characteristic of nuclear DNA fragmentation, which is typically observed in radiation-induced programmed cell death, i.e. apoptosis, in mammalian cells. On the other hand, cell death with nuclear DNA fragmentation did not develop by X-ray irradiation in vegetative cells including meristematic cells of Japanese cedar. This suggests that an apoptosis-like programmed cell death should develop cell-specifically in embryogenic cells by ionizing radiation. The abortion of embryogenic cells may work to prevent transmission of radiation-induced genetic damages to the descendants. (author)

The behavior of 137Cs in the soil-forest plants system

International Nuclear Information System (INIS)

Spiridonov, S.; Fesenko, S.; Avila, R.

1999-01-01

A model has been developed which simulates the behavior of 137 Cs in forest litter and soil, as well as seasonal and long-term dynamics of 137 CS content in forest plants. The long-term cycles of 137 CS migration are described as an integrated result of multiple annual cycles. The model results demonstrate a satisfactory coincidence with the experimental data. A set of model parameters is provided for each of four different types of forest (coniferous and deciduous forest; automorphic and semi-hydromorphic landscapes). The model allows an evaluation of the effects of countermeasures implemented in the contaminated forest. Refs. 1 (author)

Fire performance in traditional silvicultural and fire and fire surrogate treatments in Sierran mixed-conifer forests: a brief summary

Science.gov (United States)

Jason J. Moghaddas; Scott L. Stephens

2007-01-01

Mixed conifer forests cover 7.9 million acres of California’s total land base. Forest structure in these forests has been influenced by harvest practices and silvicultural systems implemented since the beginning of the California Gold Rush in 1849. Today, the role of fire in coniferous forests, both in shaping past stand structure and its ability to shape future...

Statistical data on forest fund of Russia and changing of forest productivity in the second half of XX century

Science.gov (United States)

Alexeyev V.A.; Markov M.V.; R.A. Birdsey; Birdsey R.A.

2004-01-01

Contains statistical data on area and growing-stock volume of forest lands in Oblasts, Krays and Republics of Russian Federation, for the period 1961-1998. Positive dynamics of average growing stock for coniferous, deciduous hardwood and deciduous softwood tree stands by stand-age groups were disclosed. The impact of main anthropogenic and natural factors, including...

Absorption of Power Plants СО2 Emissions by Coniferous Tree Stands

Directory of Open Access Journals (Sweden)

Suvorova G.G.

2015-12-01

Full Text Available The article reviews the ability of coniferous (common pine, siberian larch and siberian spruce stands growing in 9 municipal districts of the Irkutsk region to absorb СО2 technogenic emission of heat power plants. (EIGAF index is suggested to characterize gas-absorbing (СО2–absorbing activity; the index reflects proportion between СО2 technogenic emission and photosynthetic productivity (GPP of coniferous tree stands. СО2–absorbing capacity in 8 of the monitored districts has been shown to significantly exceed the amount of carbon dioxide emission from heat power sector. The index values EIGAF=0.01-0.97 demonstrate that СО2 technogenic emission amounts to 1-97% of coniferous stands photosynthetic productivity in the areas under study. At the same time, the most industrially developed Angarsk district shows СО2 photosynthetic absorption to be 8-12 times lower than technogenic СО2 emission. Reasons of low gas-absorbing capacity of coniferous tree stands of this area are discussed.

The short-term effects of management changes on watertable position and nutrients in shallow groundwater in a harvested peatland forest.

Science.gov (United States)

Finnegan, J; Regan, J T; Fenton, O; Lanigan, G J; Brennan, R B; Healy, M G

2014-09-01

Management changes such as drainage, fertilisation, afforestation and harvesting (clearfelling) of forested peatlands influence watertable (WT) position and groundwater concentrations of nutrients. This study investigated the impact of clearfelling of a peatland forest on WT and nutrient concentrations. Three areas were examined: (1) a regenerated riparian peatland buffer (RB) clearfelled four years prior to the present study (2) a recently clearfelled coniferous forest (CF) and (3) a standing, mature coniferous forest (SF), on which no harvesting took place. The WT remained consistently below 0.3 m during the pre-clearfelling period. Results showed there was an almost immediate rise in the WT after clearfelling and a rise to 0.15 m below ground level (bgl) within 10 months of clearfelling. Clearfelling of the forest increased dissolved reactive phosphorus concentrations (from an average of 28-230 μg L(-1)) in the shallow groundwater, likely caused by leaching from degrading brash mats. Copyright © 2014 Elsevier Ltd. All rights reserved.

Soil and soil cover changes in spruce forests after final logging

Directory of Open Access Journals (Sweden)

E. M. Lapteva

2015-10-01

Full Text Available Soil cover transformation and changes of morphological and chemical properties of Albeluvisols in clear-cuttings of middle taiga spruce forests were studied. The observed changes in structure and properties of podzolic texturally-differentiated soils at cuttings of spruce forests in the middle taiga subzone do not cause their transition to any other soil type. Soil cover of secondary deciduous-coniferous forests which replace cut forests are characterized with a varied soil contour and a combination of the main type of podzolic soils under undisturbed spruce forests. The increased surface hydromorphism in cut areas causes formation of complicated sub-types of podzolic texturally differentiated soils (podzolic surface-gley soils with microprofile of podzol and enlarges their ratio (up to 35–38 % in soil cover structure. Temporary soil over-wetting at the initial (5–10 years stage of after-cutting self-restoring vegetation succession provides for soil gleyzation, improves yield and segregation of iron compounds, increases the migratory activity of humic substances. Low content and resources of total nitrogen in forest litters mark anthropogenic transformation processes of podzolic soils at this stage. Later (in 30–40 years after logging, soils in cut areas still retain signs of hydromorphism. Forest litters are denser, less acidic and thick with a low weight ratio of organic carbon as compared with Albeluvisols of undisturbed spruce forest. The upper mineral soil horizons under secondary deciduous-coniferous forests contain larger amounts of total iron, its mobile (oxalate-dissolvable components, and Fe-Mn-concretions.

Stasis and convergence characterize morphological evolution in eupolypod II ferns.

Science.gov (United States)

Sundue, Michael A; Rothfels, Carl J

2014-01-01

Patterns of morphological evolution at levels above family rank remain underexplored in the ferns. The present study seeks to address this gap through analysis of 79 morphological characters for 81 taxa, including representatives of all ten families of eupolypod II ferns. Recent molecular phylogenetic studies demonstrate that the evolution of the large eupolypod II clade (which includes nearly one-third of extant fern species) features unexpected patterns. The traditional 'athyrioid' ferns are scattered across the phylogeny despite their apparent morphological cohesiveness, and mixed among these seemingly conservative taxa are morphologically dissimilar groups that lack any obvious features uniting them with their relatives. Maximum-likelihood and maximum-parsimony character optimizations are used to determine characters that unite the seemingly disparate groups, and to test whether the polyphyly of the traditional athyrioid ferns is due to evolutionary stasis (symplesiomorphy) or convergent evolution. The major events in eupolypod II character evolution are reviewed, and character and character state concepts are reappraised, as a basis for further inquiries into fern morphology. Characters were scored from the literature, live plants and herbarium specimens, and optimized using maximum-parsimony and maximum-likelihood, onto a highly supported topology derived from maximum-likelihood and Bayesian analysis of molecular data. Phylogenetic signal of characters were tested for using randomization methods and fitdiscrete. The majority of character state changes within the eupolypod II phylogeny occur at the family level or above. Relative branch lengths for the morphological data resemble those from molecular data and fit an ancient rapid radiation model (long branches subtended by very short backbone internodes), with few characters uniting the morphologically disparate clades. The traditional athyrioid ferns were circumscribed based upon a combination of

Elevated uptake of Th and U by netted chain fern (Woodwardia areolata)

International Nuclear Information System (INIS)

Knox, A.S.; Kaplan, D.I.; Hinton, T.G.

2008-01-01

We assessed the ability of netted chain fern (Woodwardia areolata) to uptake U and Th from wetland soils on the U.S. Department of Energy's Savannah River Site in South Carolina. Netted chain fern had the highest Th and U concentrations of all plants collected from the wetland. Ferns grown in contaminated soil (329 mg x kg -1 Th, 44 mg x kg -1 U) in a greenhouse contained 6.4 mg x kg -1 Th and 5.3 mg x kg -1 U compared with 0.13 mg x kg -1 Th and 0.035 mg x kg -1 U in Bermuda grass (Cynodon dactylon). Netted chain fern has potential for the phytoremediation of soils contaminated with Th and U. (author)

Response diversity, functional redundancy, and post-logging productivity in northern temperate and boreal forests.

Science.gov (United States)

Correia, David Laginha Pinto; Raulier, Frédéric; Bouchard, Mathieu; Filotas, Élise

2018-04-19

The development of efficient ecosystem resilience indicators was identified as one of the key research priorities in the improvement of existing sustainable forest management frameworks. Two indicators of tree diversity associated with ecosystem functioning have recently received particular attention in the literature: functional redundancy (FR) and response diversity (RD). We examined how these indicators could be used to predict post-logging productivity in forests of Québec, Canada. We analysed the relationships between pre-logging FR and RD, as measured with sample plots, and post-logging productivity, measured as seasonal variation in enhanced vegetation index obtained from MODIS satellite imagery. The effects of the deciduous and coniferous tree components in our pre-disturbance diversity assessments were isolated in order to examine the hypothesis that they have different impacts on post-disturbance productivity. We also examined the role of tree species richness and species identity effects. Our analysis revealed the complementary nature of traditional biodiversity indicators and trait-based approaches in the study of biodiversity-ecosystem-functioning relationships in dynamic ecosystems. We report a significant and positive relationship between pre-disturbance deciduous RD and post-disturbance productivity, as well as an unexpected significant negative effect of coniferous RD on productivity. This negative relationship with post-logging productivity likely results from slower coniferous regeneration speeds and from the relatively short temporal scale examined. Negative black-spruce-mediated identity effects were likely associated with increased stand vulnerability to paludification and invasion by ericaceous shrubs that slow down forest regeneration. Response diversity outperformed functional redundancy as a measure of post-disturbance productivity most likely due to the stand-replacing nature of the disturbance considered. To the best of our knowledge

Here today, here tomorrow: Managing forests for fisher habitat in the Northern Rockies

Science.gov (United States)

Sue Miller; Michael Schwartz; Lucretia E. Olson

2016-01-01

The fisher is a unique member of the weasel family and a sensitive species in the northern Rockies. They were almost extirpated by trapping in the early twentieth century, but these animals (a mix between a native and introduced population) now inhabit a swath of mesic coniferous forests in Idaho and Montana. Forest managers need information on fisher distribution and...

The measurement of Cs-137 in Latvian forest litter

International Nuclear Information System (INIS)

Riekstina, D.; Veveris, O.

1998-01-01

The role of forests in the distribution of cesium 137 over the Latvian territory affected by the Chernobyl accident was examined. Concentrations of this radionuclide in soil in pine, spruce, and birch forests and in non-forest areas in Rucava (affected by the accident) and in Taurene (non-polluted zone) were compared. In Rucava, the concentrations of Cs-137 fluctuated over the region of 108-724 Bq/kg in a pine forest, 205-2270 Bq/kg in a spruce forest, and 15-30 Bq/kg beyond the forest region. In Taurene, the corresponding figures were 42-157, 19-133, and 3-19 Bq/kg, respectively. The data confirm the appreciable role of coniferous forests in the absorption of Cs-137 from the air and its redistribution within the forest area. (P.A.)

PIXE study on absorption of arsenate and arsenite by arsenic hyperaccumulating fern (Pteris vittata)

International Nuclear Information System (INIS)

Yamazaki, H.; Ishii, K.; Matsuyama, S.

2008-01-01

Pytoremediation using an arsenic hyperaccumulator, Petris vittata L., has generated an increasing interest worldwide due to both environmentally sound and cost effectiveness. However the mechanism of arsenic accumulation by this fern is not clear at this time. This study examined the uptake of arsenate (As(V)) and arsenite (As(III)) by a hydroponic culture of Pteris vittata using both in-air submilli-PIXE for different parts of the fern and in-air micro-PIXE for the tissue cells. These PIXE analysis systems used 3 MeV proton beams from a 4.5-MV single-ended Dynamitron accelerator at Tohoku University, Japan. The fern took up both arsenate and arsenite from hydroponic solutions which were spiked with 50 mg of arsenic per litter. Final amount of arsenic accumulation in the fern is 1,500 mg per kg (wet weight) of the plant biomass in arsenite treatment and 1,100 mg per kg in arsenate treatment. Arsenic accumulation was not observed at the root parts of the ferns. The in-vivo mapping of elements by submilli-PIXE analyses on the fern laminas showed the arsenic accumulation in the edges of a pinna. The micro-PIXE analyses revealed arsenic maps homogeneously distributed in cells of the lamina, stem and rhizome of the fern. These results indicate that arsenic, both arsenate and arsenite in a contaminated medium are translocated quickly from roots to fronds of Pteris vittata, and distributes homogeneously into tissue cells of the fern laminas. (author)

The role of bracken (Pteridium aquilinum) in forest dynamics = [De rol van adelaarsvaren (Pteridium aquilinum) in de bosdynamiek

NARCIS (Netherlands)

Ouden, den J.

2000-01-01

Bracken fern ( Pteridium aquilinum ) causes stagnation in forest succession in many parts of the world. The mechanisms by which bracken affects the establishment and growth of plant species are studied, focusing on the regeneration of tree species in forest

High gene flow in epiphytic ferns despite habitat loss and fragmentation.

Science.gov (United States)

Winkler, Manuela; Koch, Marcus; Hietz, Peter

2011-01-01

Tropical montane forests suffer from increasing fragmentation and replacement by other types of land-use such as coffee plantations. These processes are known to affect gene flow and genetic structure of plant populations. Epiphytes are particularly vulnerable because they depend on their supporting trees for their entire life-cycle. We compared population genetic structure and genetic diversity derived from AFLP markers of two epiphytic fern species differing in their ability to colonize secondary habitats. One species, Pleopeltis crassinervata , is a successful colonizer of shade trees and isolated trees whereas the other species, Polypodium rhodopleuron , is restricted to forests with anthropogenic separation leading to significant isolation between populations. By far most genetic variation was distributed within rather than among populations in both species, and a genetic admixture analysis did not reveal any clustering. Gene flow exceeded by far the benchmark of one migrant per generation to prevent genetic divergence between populations in both species. Though populations are threatened by habitat loss, long-distance dispersal is likely to support gene flow even between distant populations, which efficiently delays genetic isolation. Consequently, populations may rather be threatened by ecological consequences of habitat loss and fragmentation.

Exchange processes between a coniferous forest and the atmosphere

NARCIS (Netherlands)

Bosveld, F.C.

1999-01-01

This thesis deals with the research question: which processes are relevant in controlling the exchange fluxes between the forest and the atmosphere and how can this control be quantified? Answering this question is relevant for research in the fields of air pollution, weather and climate

Multivariate Analysis of Some Pine Forested Areas of Azad Kashmir-Pakistan

International Nuclear Information System (INIS)

Bokhari, T.Z.; Liu, Y.; Li, Q.; Malik, S.A.; Ahmed, M.; Siddiqui, M.F.; Khan, Z.U.

2016-01-01

Floristic composition and communities in Azad Kashmir area of Pakistan were studied by using multivariate analysis. Quantitative sampling from thirty one sites was carried out in different coniferous forests of Azad Kashmir in order to analyze the effects of past earthquakes and landslides on vegetation of these areas. Though coniferous forests were highly disturbed either naturally or anthropogenic activities, therefore sampling was preferred to those forests which were near fault line. Trees were sampled using Point Centered Quarter (PCQ) method. Results of cluster analysis (using Ward's method) yielded six groups dominated by different conifer species. Group I and V were dominated by Pinus wallichiana while this species was co-dominant in group III. Other groups showed the dominance of different conifer species i.e. Cedrus deodara, Pinus roxburghii, Picea smithiana and Abies pindrow. Both the cluster analysis and ordination techniques (by two dimensional non-metric multidimensional scaling) classify and ordinate the structure of various groups indicating interrelationship among different species. The groups of trees were readily be superimposed on NMS ordination axes; they were well classified and well separated out in ordination. The present research revealed that these forests had diverse and asymmetric structure due to natural anthropogenic disturbances and overgrazing, which were key factors in addition to natural disturbances. However, some of the forests showed considerably stable structure due to less human interference. (author)

Accumulation of policyclic aromatic hydrocarbons (PAHs) in surface litter and soils in four forests in the United States

Science.gov (United States)

Obrist, D.; Perlinger, J. A.; Zielinska, B.

2014-12-01

Polycyclic aromatic hydrocarbons (PAHs) are toxic environmental pollutants originating from the incomplete combustion of organic material, both from natural or anthropogenic sources. Once emitted, they can be transported across thousands of kilometers impacting remote environments. Here, we characterize the distribution of 23 PAHs and 9 oxygenated PAHs (Σ32PAH) in litter and soils in four remote forests in the United States. Concentrations of Σ32PAH in fresh surface litter (Oi layers) showed very low levels in three of the four forests (mixed coniferous forest in Maine, deciduous blue oak forest in California, and a coniferous forest in Washington State), with PAHs levels much lower than those reported in previous studies from Europe. The analysis showed that PAHs represented a mix of regional background sources. Highest PAH levels were observed in a coniferous forest floor in Florida, attributable to frequent prescribed burning of understory vegetation at this site, and supported by high contributions of retene (>7%; compared to atmospheric deposition. Within mineral soils, Σ32PAH:OC ratios increased with depth (Ah horizons: 750±198 ng g-1; B horizons: 1,202±97 ng g-1), indicating that vertical transfer in mineral soils leads to significant accumulation of PAH in subsoils. ΣPAH:OC increases observed in deeper soil layers may be attributed to slower mineralization rates of PAHs compared to OC, plus vertical transport as indicated by preferential enrichment of PAHs with low Kow (i.e., more water-soluble PAHs). Finally, percentage of potentially biologically produced PAH (Σ Naph+Phen+Pery) were low and consistent across the litter/soil horizons, suggesting that biological production is minor or absent at our sites.

Non-timber forest products in Central Appalachia: market opportunities for rural development (poster abstract)

Science.gov (United States)

A.L. Hammett; J.L. Chamberlain

1999-01-01

The gathering of forest products has supplemented the incomes of Central Appalachia residents for many generations. Non-timber forest products (NTFPs) can be grouped within four general categories: edibles such as mushrooms; medicinal and dietary supplements, including ginseng, gingko, and St. John?s wort; floral products such as moss, grape vines, and ferns; and...

Natural regeneration in abandoned fields following intensive agricultural land use in an Atlantic Forest Island, Brazil

Directory of Open Access Journals (Sweden)

Milene Silvestrini

2012-08-01

Full Text Available The time required to regrowth a forest in degraded areas depends on how the forest is removed and on the type of land use following removal. Natural regeneration was studied in abandoned old fields after intensive agricultural land use in areas originally covered by Brazilian Atlantic Forests of the Anchieta Island, Brazil in order to understand how plant communities reassemble following human disturbances as well as to determine suitable strategies of forest restoration. The fields were classified into three vegetation types according to the dominant plant species in: 1 Miconia albicans (Sw. Triana (Melastomataceae fields, 2 Dicranopteris flexuosa (Schrader Underw. (Gleicheniaceae thickets, and 3 Gleichenella pectinata (Willd. Ching. (Gleicheniaceae thickets. Both composition and structure of natural regeneration were compared among the three dominant vegetation types by establishing randomly three plots of 1 x 3 m in five sites of the island. A gradient in composition and abundance of species in natural regeneration could be observed along vegetation types from Dicranopteris fern thickets to Miconia fields. The gradient did not accurately follow the pattern of spatial distribution of the three dominant vegetation types in the island regarding their proximity of the remnant forests. A complex association of biotic and abiotic factors seems to be affecting the seedling recruitment and establishment in the study plots. The lowest plant regeneration found in Dicranopteris and Gleichenella thickets suggests that the ferns inhibit the recruitment of woody and herbaceous species. Otherwise, we could not distinguish different patterns of tree regeneration among the three vegetation types. Our results showed that forest recovery following severe anthropogenic disturbances is not direct, predictable or even achievable on its own. Appropriated actions and methods such as fern removal, planting ground covers, and enrichment planting with tree species were

Antibacterial and antifungal effects of essential oils from coniferous trees.

Science.gov (United States)

Hong, Eui-Ju; Na, Ki-Jeung; Choi, In-Gyu; Choi, Kyung-Chul; Jeung, Eui-Bae

2004-06-01

Essential oils have potential biological effects, i.e., antibiotic, anticarcinogenic, and sedative effects during stress. In the present study, we investigated the antibacterial and antifungal effects of essential oils extracted from the coniferous species Pinus densiflora, Pinus koraiensis, and Chamaecyparis obtusa, because their biological activities have not been yet elucidated. The essential oils were quantified using gas chromatography and identified in gas chromatography-mass spectrometric analysis. Simultaneously, antibacterial and antifungal assays were performed using the essential oils distilled from the needles of coniferous trees. The major components and the percentage of each essential oil were: 19.33% beta-thujene in P. densiflora; 10.49% alpha-pinene in P. koraiensis; 10.88% bornyl acetate in C. obtusa. The essential oils from P. densiflora and C. obtusa have antibacterial effects, whereas essential oils from P. koraiensis and C. obtusa have antifungal effects. These results indicate that the essential oils from the three coniferous trees, which have mild antimicrobial properties, can inhibit the growth of gram-positive and gram-negative bacteria and fungi.

Response of mountain Picea abies forests to stand-replacing bark beetle outbreaks: Neighbourhood effects lead to self-replacement

Science.gov (United States)

Thorsten Zeppenfeld; Miroslav Svoboda; R. Justin DeRose; Marco Heurich; Jorg Muller; Pavla Cizkova; Martin Stary; Radek Bace; Daniel C. Donato

2015-01-01

Large, severe disturbances drive many forest ecosystems over the long term, but pose management uncertainties when human experience with them is limited. Recent continent-scale outbreaks of bark beetles across the temperate Northern Hemisphere have raised major concerns as to whether coniferous forests will regenerate back towards pre-outbreak condition and...

Microclimate, Water Potential, Transpiration, and Bole Dielectric Constant of Coniferous and Deciduous Tree Species in the Continental Boreal Ecotone of Central Alaska

Science.gov (United States)

Zimmermann, R.; McDonald, K.; Way, J.; Oren, R.

1994-01-01

Tree canopy microclimate, xylem water flux and xylem dielectric constant have been monitored in situ since June 1993 in two adjacent natural forest stands in central Alaska. The deciduous stand represents a mature balsam poplar site on the Tanana River floodplain, while the coniferous stand consists of mature white spruce with some black spruce mixed in. During solstice in June and later in summer, diurnal changes of xylem water potential were measured to investigate the occurrence and magnitude of tree transpiration and dielectric constant changes in stems.

Potential consequences of climate variability and change for the forests of the United States

Science.gov (United States)

Linda Joyce; John Aber; Steve McNulty; virginia Dale; Andrew Hansen; Lloyd Irland; Ron Neilson; Kenneth Skog

2001-01-01

Forests cover nearly one-third of the US,providing wildlife habitat, clean air and water, cultural and aesthetic values,carbon storage, recreational opportunities such as hiking,camping, fishing,and autumn leaf tours,and products that can be harvested such as timber, pulpwood,fuelwood,wild game, ferns, mushrooms,and berries. This wealth depends on forest biodiversity—...

Results of 90Sr and 239+240Pu, 238Pu, 241Am measurements in some samples of mushrooms and forest soil from Poland

International Nuclear Information System (INIS)

Mietelski, J.W.; Larosa, J.; Ghods, A.

1992-01-01

Strontium-90, plutonium and americium activity concentrations in a few samples of forest soils, some species of mushrooms and fern leaves were determined. These results are compared with caesium activity concentrations in the same materials obtained in a previous work. Radiochemical procedures are described. The origin of the contamination (Chernobyl accident or nuclear test explosion release) is discussed. The 90 Sr activity concentration ranges from 0.6 Bq/kg (mushroom samples) to 48.4 Bq/kg (fern leaves). For 239+240 Pu, it ranges from not detected above background (mushrooms, fern) to 10.8 Bq/kg (humus layer of forest soil). The maximum concentration of 241 Am is found to be 2.4 Bq/kg (humus sample) and for 238 Pu it is 0.85 Bq/kg (also in the humus sample). (author). 12 refs, 9 figs, 7 tabs

Somatic embryogenesis in ferns: a new experimental system.

Science.gov (United States)

Mikuła, Anna; Pożoga, Mariusz; Tomiczak, Karolina; Rybczyński, Jan J

2015-05-01

Somatic embryogenesis has never been reported in ferns. The study showed that it is much easier to evoke the acquisition and expression of embryogenic competence in ferns than in spermatophytes. We discovered that the tree fern Cyathea delgadii offers an effective model for the reproducible and rapid formation of somatic embryos on hormone-free medium. Our study provides cyto-morphological evidence for the single cell origin and development of somatic embryos. Somatic embryogenesis (SE) in both primary and secondary explants was induced on half-strength micro- and macro-nutrients Murashige and Skoog medium without the application of exogenous plant growth regulators, in darkness. The early stage of SE was characterized by sequential perpendicular cell divisions of an individual epidermal cell of etiolated stipe explant. These resulted in the formation of a linear pro-embryo. Later their development resembled that of the zygotic embryo. We defined three morphogenetic stages of fern somatic embryo development: linear, early and late embryonic leaf stage. The transition from somatic embryo to juvenile sporophyte was quick and proceeded without interruption caused by dormancy. Following 9 weeks of culture the efficiency of somatic embryogenesis reached 12-13 embryos per responding explant. Spontaneous formation of somatic embryos and callus production, which improved the effectiveness of the process sevenfold in 10-month-long culture, occurred without subculturing. The tendency for C. delgadii to propagate by SE in vitro makes this species an excellent model for studies relating to asexual embryogenesis and the endogenous hormonal regulation of that process and opens new avenues of experimentation.

The fern sporangium: an ultrafast natural catapult

Science.gov (United States)

Noblin, Xavier; Argentina, Mederic; Westbrook, Jared; Llorens, Coraline; Rojas, Nicolas; Dumais, Jacques

2012-02-01

Plants have developed fascinating mechanisms to create ultra fast movements that often reach the upper limit allowed by physical laws. Inspiration for new technologies is one of the reasons for the strong interest for these mechanisms, along with the deep interest of understanding complex, natural systems. The fern sporangium is a capsule that contains the spores, it is surrounded by a row of cells called the annulus which acts as a beam. Due to the water evaporation from its cells, the annulus bends strongly and induces elastic energy storage during an opening phase. The tension in the cells breaks when cavitation bubbles appear in the cells, leading to a fast release of the elastic energy. The fern sporangium then acts as a catapult which ejects rapidly its spores by closing back to the initial closed shape. We have analyzed the slow opening motion and the fast catapulting mechanism. We found that the catapult motion involves two time scales, showing a very original behavior. In man-made catapults, the recoil motion needs to be arrested by a cross bar so that the projectile is released from the arm. We show here that the fern sporangium replaces the essential cross bar by an elegant poroelastic damping, leading to a completely autonomous, efficient device.

Ponderosa pine, mixed conifer, and spruce-fir forests [Chapter 2

Science.gov (United States)

Michael A. Battaglia; Wayne D. Shepperd

2007-01-01

Before European settlement of the interior west of the United States, coniferous forests of this region were influenced by many disturbance regimes, primarily fires, insects, diseases, and herbivory, which maintained a diversity of successional stages and vegetative types across landscapes. Activities after settlement, such as fire suppression, grazing, and logging...

Fern Stomatal Responses to ABA and CO2 Depend on Species and Growth Conditions.

Science.gov (United States)

Hõrak, Hanna; Kollist, Hannes; Merilo, Ebe

2017-06-01

Changing atmospheric CO 2 levels, climate, and air humidity affect plant gas exchange that is controlled by stomata, small pores on plant leaves and stems formed by guard cells. Evolution has shaped the morphology and regulatory mechanisms governing stomatal movements to correspond to the needs of various land plant groups over the past 400 million years. Stomata close in response to the plant hormone abscisic acid (ABA), elevated CO 2 concentration, and reduced air humidity. Whether the active regulatory mechanisms that control stomatal closure in response to these stimuli are present already in mosses, the oldest plant group with stomata, or were acquired more recently in angiosperms remains controversial. It has been suggested that the stomata of the basal vascular plants, such as ferns and lycophytes, close solely hydropassively. On the other hand, active stomatal closure in response to ABA and CO 2 was found in several moss, lycophyte, and fern species. Here, we show that the stomata of two temperate fern species respond to ABA and CO 2 and that an active mechanism of stomatal regulation in response to reduced air humidity is present in some ferns. Importantly, fern stomatal responses depend on growth conditions. The data indicate that the stomatal behavior of ferns is more complex than anticipated before, and active stomatal regulation is present in some ferns and has possibly been lost in others. Further analysis that takes into account fern species, life history, evolutionary age, and growth conditions is required to gain insight into the evolution of land plant stomatal responses. © 2017 American Society of Plant Biologists. All Rights Reserved.

rbcL gene sequences provide evidence for the evolutionary lineages of leptosporangiate ferns.

Science.gov (United States)

Hasebe, M; Omori, T; Nakazawa, M; Sano, T; Kato, M; Iwatsuki, K

1994-06-07

Pteriodophytes have a longer evolutionary history than any other vascular land plant and, therefore, have endured greater loss of phylogenetically informative information. This factor has resulted in substantial disagreements in evaluating characters and, thus, controversy in establishing a stable classification. To compare competing classifications, we obtained DNA sequences of a chloroplast gene. The sequence of 1206 nt of the large subunit of the ribulose-bisphosphate carboxylase gene (rbcL) was determined from 58 species, representing almost all families of leptosporangiate ferns. Phlogenetic trees were inferred by the neighbor-joining and the parsimony methods. The two methods produced almost identical phylogenetic trees that provided insights concerning major general evolutionary trends in the leptosporangiate ferns. Interesting findings were as follows: (i) two morphologically distinct heterosporous water ferns, Marsilea and Salvinia, are sister genera; (ii) the tree ferns (Cyatheaceae, Dicksoniaceae, and Metaxyaceae) are monophyletic; and (iii) polypodioids are distantly related to the gleichenioids in spite of the similarity of their exindusiate soral morphology and are close to the higher indusiate ferns. In addition, the affinities of several "problematic genera" were assessed.

Sorption equilibrium of mercury onto ground-up tree fern.

Science.gov (United States)

Ho, Yuh-Shan; Wang, Chung-Chi

2008-08-15

The sorption behavior of mercury at different temperatures onto ground-up tree fern was investigated. The experimental results were fitted to two two-parameter isotherms, the Freundlich and Langmuir isotherms, as well as to two three-parameter isotherms, the Redlich-Peterson and Sips isotherms to obtain the characteristic parameters of each model. A comparison of best-fitting was performed using the coefficient of determination and Chi-square test. Both the Langmuir and Redlich-Peterson isotherms were found to well represent the measured sorption data. According to the evaluation using the Langmuir equation, the saturated monolayer sorption capacity of mercury ions onto ground-up tree fern was 26.5 mg/g at 298 K. It was noted that an increase in temperature resulted in a higher mercury ion loading per unit weight of the tree fern. In addition, various thermodynamic parameters, such as DeltaG degrees, DeltaH degrees, and DeltaS degrees, were calculated and compared with the sorption of mercury by other sorbents.

Sorption equilibrium of mercury onto ground-up tree fern

International Nuclear Information System (INIS)

Ho, Y.-S.; Wang, C.-C.

2008-01-01

The sorption behavior of mercury at different temperatures onto ground-up tree fern was investigated. The experimental results were fitted to two two-parameter isotherms, the Freundlich and Langmuir isotherms, as well as to two three-parameter isotherms, the Redlich-Peterson and Sips isotherms to obtain the characteristic parameters of each model. A comparison of best-fitting was performed using the coefficient of determination and Chi-square test. Both the Langmuir and Redlich-Peterson isotherms were found to well represent the measured sorption data. According to the evaluation using the Langmuir equation, the saturated monolayer sorption capacity of mercury ions onto ground-up tree fern was 26.5 mg/g at 298 K. It was noted that an increase in temperature resulted in a higher mercury ion loading per unit weight of the tree fern. In addition, various thermodynamic parameters, such as ΔG o , ΔH o , and ΔS o , were calculated and compared with the sorption of mercury by other sorbents

Sorption equilibrium of mercury onto ground-up tree fern

Energy Technology Data Exchange (ETDEWEB)

Ho, Y.-S. [Department of Chemical Engineering, I-Shou University, No. 1, Section 1, Hsueh-Cheng Road, Ta-Hsu Hsiang, Kaohsiung County 840, Taiwan (China)], E-mail: ysho@isu.edu.tw; Wang, C.-C. [Department of Chemical Engineering, I-Shou University, No. 1, Section 1, Hsueh-Cheng Road, Ta-Hsu Hsiang, Kaohsiung County 840, Taiwan (China)

2008-08-15

The sorption behavior of mercury at different temperatures onto ground-up tree fern was investigated. The experimental results were fitted to two two-parameter isotherms, the Freundlich and Langmuir isotherms, as well as to two three-parameter isotherms, the Redlich-Peterson and Sips isotherms to obtain the characteristic parameters of each model. A comparison of best-fitting was performed using the coefficient of determination and Chi-square test. Both the Langmuir and Redlich-Peterson isotherms were found to well represent the measured sorption data. According to the evaluation using the Langmuir equation, the saturated monolayer sorption capacity of mercury ions onto ground-up tree fern was 26.5 mg/g at 298 K. It was noted that an increase in temperature resulted in a higher mercury ion loading per unit weight of the tree fern. In addition, various thermodynamic parameters, such as {delta}G{sup o}, {delta}H{sup o}, and {delta}S{sup o}, were calculated and compared with the sorption of mercury by other sorbents.

Energy balance of a sparse coniferous high-latitude forest under winter conditions

DEFF Research Database (Denmark)

Gryning, Sven-Erik; Batchvarova, E.; Bruin, H.A.R. de

2001-01-01

was simulated for a three month period. For conditions with a cloud cover of less than 7 oktas good agreement between model predictions and measurements were found. For cloud cover 7 and 8 oktas a considerable spread can be observed. To apply the proposed energy balance model, the global radiation must......Measurements carried out in Northern Finland on radiation and turbulent fluxes over a sparse, sub-arctic boreal forest with snow covered ground were analysed. The measurements represent late winter conditions characterised by low solar elevation angles. During the experiment (12-24 March 1997) day...... and night were about equally long. At low solar elevation angles the forest shades most of the snow surface. Therefore an important part of the radiation never reaches the snow surface but is absorbed by the forest. The sensible heat flux above the forest was fairly large, reaching more than 100 W m(-2...

Vegetation assessment of forests of Pagan Island, Commonwealth of the Northern Mariana Islands

Science.gov (United States)

Pratt, Linda W.

2011-01-01

As part of the Marianas Expedition Wildlife Surveys-2010, the forest vegetation of the island of Pagan, Commonwealth of the Northern Mariana Islands (CNMI), was sampled with a series of systematic plots along 13 transects established for monitoring forest bird populations. Shrubland and grassland were also sampled in the northern half of the island. Data collected were woody plant density, tree diameter at breast height, woody plant density in height classes below 2 m, and ground cover measured with the point-intercept method. Coconut forests (Cocos nucifera) were generally found to have low native tree diversity, little regeneration of trees and shrubs in the forest understory, and little live ground cover. The sole exception was a coconut-dominated forest of the northeast side of the island that exhibited high native tree diversity and a large number of young native trees in the understory. Ironwood (Casuarina equisetifolia) forests on the northern half of the island were nearly monocultures with almost no trees other than ironwood in vegetation plots, few woody plants in the understory, and low ground cover dominated by native ferns. Mixed native forests of both northern and southern sections of the island had a diversity of native tree species in both the canopy and the sparse understory. Ground cover of native forests in the north had a mix of native and alien species, but that of the southern half of the island was dominated by native ferns and woody plants.

Root hydraulic vulnerability regulation of whole-plant conductance along hillslope gradients within subalpine and montane forests

Science.gov (United States)

Beverly, D.; Speckman, H. N.; Ewers, B. E.

2017-12-01

Ecosystem-scale models often rely on root vulnerability or whole-plant conductance for simulating seasonal evapotranspiration declines via constraints of water uptake and vegetation mortality. Further, many of these ecosystem models rely on single, unvarying, hydraulic parameter estimates for modeling large areas. Ring-porous species have shown seasonal variability in root vulnerability (percent loss of conductivity; PLC) and whole-plant conductance (Kw) but simulations of coniferous forest typically rely on point measurements. This assumption for coniferous forest is not likely true because of seasonal variability caused by phenology and environmental stresses and the potential for cavitation fatigue is not considered. Moreover, many of these dynamics have only been considered for stems even though roots are often the most vulnerable segments of the pathway for conifers. We hypothesized that seasonally dynamic whole-plant conductance along hillslope gradients in coniferous forests are regulated by cavitation fatigue within the roots resulting in seasonal increases in vulnerability. To test the hypothesis, a subalpine mixed forest (3000 m.a.s.l) and montane forest (2550 m.a.s.l.) were monitored between 2015-2017 to quantify PLC and Kw along the hillslope gradients of 300 m and 50 m, respectively. Forest plots were instrumented with 35 Granier-type sapflow sensors. Seasonal sampling campaigns occurred to quantify PLC through centrifuge techniques and Kw through Darcy's law approximations with pre-dawn and diurnal leaf water potentials. Downslope roots exhibit a 33% decrease in maximal conductivity corresponding to the approximately 50% decrease in whole-plant conductance suggesting seasonal soil dry-down limitations within the downslope stands. Upslope stands had no to little change in root vulnerability or decrease in whole-plant conductance as soil water limitations occur immediately following snowmelt, thus limiting hydraulic conductance throughout the growing

[Dynamics of total organic carbon (TOC) in hydrological processes in coniferous and broad-leaved mixed forest of Dinghushan].

Science.gov (United States)

Yin, Guangcai; Zhou, Guoyi; Zhang, Deqiang; Wang, Xu; Chu, Guowei; Liu, Yan

2005-09-01

The total flux and concentration of total organic carbon (TOC) in hydrological processes in coniferous and broad-leaved mixed forest of Dinghushan were measured from July 2002 to July 2003. The results showed that the TOC input by precipitation was 41.80 kg x hm(-2) x yr(-1), while its output by surface runoff and groundwater (soil solution at 50 cm depth) was 17.54 and 1.80 kg x hm(-2) x yr(-1), respectively. The difference between input and output was 22.46 kg x hm(-2) x yr(-1), indicating that the ecosystem TOC was in positive balance. The monthly variation of TOC flux in hydrological processes was very similar to that in precipitation. The mean TOC concentration in precipitation was 3.64 mg x L(-1), while that in throughfall and stemflow increased 6.10 and 7.39 times after rain passed through the tree canopies and barks. The mean TOC concentration in surface runoff and in soil solution at 25 and 50 cm depths was 12.72, 7.905 and 3.06 mg x L(-1), respectively. The monthly TOC concentration in throughfall and stemflow had a similar changing tendency, showing an increase at the beginning of growth season (March), a decrease after September, and a little increase in December. The TOC concentration in runoff was much higher during high precipitation months. No obvious monthly variation was observed in soil solution TOC concentration (25 and 50 cm below the surface). Stemflow TOC concentration differed greatly between different tree species. The TOC concentration in precipitation, throughfall, and soil solution (25 and 50 cm depths) decreased with increasing precipitation, and no significant relationship existed between the TOC concentrations in stemflow, surface runoff and precipitation. The TOC concentrations in the hydrological processes fluctuated with precipitation intensity, except for that in stemflow and soil solutions.

Previsual detection of two conifer-infesting adelgid species in North American forest

Science.gov (United States)

Stephen Cook; Karen Humes; Ryan Hruska; Christopher Williams; Grant Fraley

2010-01-01

The balsam woolly adelgid, Adelges piceae, and hemlock woolly adelgid, A. tsugae (Homoptera: Adelgidae), are invasive pests of coniferous forests in both the Eastern and Western United States. Balsam woolly adelgid is capable of attacking and killing native North American firs, with Fraser fir (Abies fraseri...

Peat swamp forest of Thailand

Energy Technology Data Exchange (ETDEWEB)

Niyomdham, C.; Urapeepatanapong, C.; Pitayakajornwute, P. [Pikoolthong Royal Development Study Center, Bangkok (Thailand). Royal Forest Department

1996-12-31

Peat swamp forest in Thailand occurs extensively along coastal flatlands in the central and southern parts of the country and some small patches of topogenous peatland are present locally on several mountain tops of the northern region. Many have been deteriorated by recent extensive development programs. However, one large area, about 347.04 km{sup 2}, of ombrogenous peatland is still left intact in the Pru Toh Dang area where conservation activities are being strictly enforced under one of the Royal Initiative Projects. Pru Toh Dang peat consists of 5 metres of fibrous organic soil overlying pyritic marine clay. Despite an inhospitable, submerged and unstable forest floor, the floristic composition of the peat swamp forest is extremely complicated, consisting of 124 families and 470 species of which 109 families and 437 species of flowering plants, and 15 families and 33 species of ferns recorded between 1983-1989 by a team from the Forest Herbarium of the Royal Forest Department of Thailand. (orig.) (4 refs.)

Declining plant nitrogen supply and carbon accumulation in ageing primary boreal forest ecosystems

Science.gov (United States)

Högberg, Mona N.; Yarwood, Stephanie A.; Trumbore, Susan; Högberg, Peter

2016-04-01

Boreal forest soils are commonly characterized by a low plant nitrogen (N) supply. A high tree below-ground allocation of carbon (C) to roots and soil microorganisms in response to the shortage of N may lead to high microbial immobilisation of N, thus aggravating the N limitation. We studied the N supply at a Swedish boreal forest ecosystem chronosequence created by new land rising out of the sea due to iso-static rebound. The youngest soils develop with meadows by the coast, followed by a zone of dinitrogen fixing alder trees, and primary boreal conifer forest on ground up to 560 years old. With increasing ecosystem age, the proportion of microbial C out of the total soil C pool from the youngest to the oldest coniferous ecosystem was constant (c. 1-1.5%), whereas immobilised N (microbial N out of total soil N) increased and approached the levels commonly observed in similar boreal coniferous forests (c. 6-7 %), whereas gross N mineralization declined. Simultaneously, plant foliar N % decreased and the natural abundance of N-15 in the soil increased. More specifically, the difference in N-15 between plant foliage and soil increased, which is related to greater retention of N-15 relative to N-14 by ectomycorrhizal fungi as N is taken up from the soil and some N is transferred to the plant host. In the conifer forest, where these changes were greatest, we found increased fungal biomass in the F- and H-horizons of the mor-layer, in which ectomycorrhizal fungi are known to dominate (the uppermost horizon with litter and moss is dominated by saprotrophic fungi). Hence, we propose that the decreasing N supply to the plants and the subsequent decline in plant production in ageing boreal forests is linked to high tree belowground C allocation to C limited ectomycorrhizal fungi (and other soil microorganisms), a strong sink for available soil N. Data on organic matter C-14 suggested that the largest input of recently fixed plant C occurred in the younger coniferous forest

Alvaro Fernández Pérez

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Díaz Piedrahita Santiago

1995-11-01

Full Text Available Fue el Dr. Fernández miembro destacado de la comunidad botánica latinoamericana formada hacia la mitad del siglo, y en Colombia desempeñó un papel importante como miembro de planta del Herbario Nacional Colombiano y del Instituto de Ciencias Naturales de la Facultad de Ciencias de la Universidad Nacional de Colombia. Nació el Dr. Fernández el 11 de febrero de 1920 en la procera ciudad de Popayán, donde tras adelantar los estudios primarios y secundarios obtuvo en 1940 el título de bachiller en el Liceo de la Universidad del Cauca; cumplida esta etapa se desplazó a Bogotá, ingresando a la Universidad Nacional donde completó el plan de estudios de la carrera de Farmacia e inició el curso del doctorado que se ofrecía para la época.

Regional factors rather than forest type drive the community structure of soil living oribatid mites (Acari, Oribatida).

Science.gov (United States)

Erdmann, Georgia; Scheu, Stefan; Maraun, Mark

2012-06-01

Most European forests are managed by humans. However, the manner and intensity of management vary. While the effect of forest management on above-ground communities has been investigated in detail, effects on the below-ground fauna remain poorly understood. Oribatid mites are abundant microarthropods in forest soil and important decomposers in terrestrial ecosystems. Here, we investigated the effect of four forest types (i.e., managed coniferous forests; 30 and 70 years old managed beech forests; natural beech forests) on the density, diversity and community structure of oribatid mites (Acari). The study was replicated at three regions in Germany: the Swabian Alb, the Hainich and the Schorfheide. To relate changes in oribatid mite community structure to environmental factors, litter mass, pH, C and N content of litter, fine roots and C content of soil were measured. Density of oribatid mites was highest in the coniferous forests and decreased in the order 30 years old, 70 years old, and natural beech forests. Mass of the litter layer and density of oribatid mites were strongly correlated indicating that the litter layer is an important factor regulating oribatid mite densities. Diversity of oribatid mites was little affected by forest type indicating that they harbor similar numbers of niches. Species composition differed between the forest types, suggesting different types of niches. The community structure of oribatid mites differed more strongly between the three regions than between the forest types indicating that regional factors are more important than effects associated with forest type.

Effect of 40 and 80 Years of Conifer Regrowth on Soil Microbial Activities and Community Structure in Subtropical Low Mountain Forests

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Ed-Haun Chang

2016-10-01

Full Text Available The effects of long-term reforestation on soil microbial communities and biomass are poorly understood. This study was conducted on two coniferous plantations: Cunninghamia konishii Hayata, planted 40 years ago (CONIF-40, and Calocedrus formosana (Florin Florin, planted 80 years ago (CONIF-80. An adjacent natural broadleaf forest (BROAD-Nat was used as a control. We determined microbial biomass C and N contents, enzyme activities, and community composition (via phospholipid fatty acid [PLFA] assessment. Both microbial biomass and PLFA content were higher in the summer than in the winter and differed among the forests in summer only. Total PLFA, total bacterial, gram-positive bacterial, gram-negative bacterial, and vesicular arbuscular mycorrhizal fungal contents followed the same pattern. Total fungal content and the ratios of fungi to bacteria and of gram-positive to gram-negative bacteria were highest in CONIF-40, with no difference between the other forests. Principal component analysis of PLFA contents revealed that CONIF-40 communities were distinct from those of CONIF-80 and BROAD-Nat. Our results suggest that vegetation replacement during reforestation exerts a prolonged impact on the soil microbial community. The understory broadleaf shrubs and trees established after coniferous plantation reforestation may balance out the effects of coniferous litter, contributing to bacterial recovery.

In Vitro Conservation of Some Threatened and Economically Important Ferns Belonging to the Indian Subcontinent

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Shastri P. Shukla

2014-01-01

Full Text Available This study was undertaken to identify methods of mass multiplication for five ornamental, economically important ferns (Nephrolepis biserrata (Sw. Schott., N. cordifolia cv. ‘‘duffii’’ (L. Presl., N. exaltata cv. bostoniensis (L. Schott., Pteris vittata L., and Cyclosorus dentatus Link., and three threatened ferns, namely, Cyathea spinulosa Wall. ex. Hook, Pityrogramma calomelanos (L. Link., and Microsorum punctatum (L. Schott., through in vitro techniques. Collections were made from different biodiversity zones of India including Northeast Himalayas, Kumaon Himalayas, and Western Ghat and successfully introduced and grown in a fern-house. Aseptic cultures were raised at the morphogenic level of callus, axillary shoot, multiple shoot, and rooted plants. An optimized medium is described for each fern species. Plantlets were also produced from spore culture of Cyathea spinulosa and successfully hardened under fern house conditions.

Isotope studies to determine dry deposition of sulfate to deciduous and coniferous trees: Final draft

International Nuclear Information System (INIS)

Garten, C.T. Jr.

1988-01-01

Experiments have been conducted at two locations near Oak Ridge, Tennessee, with radioactive 35 S (87 day half-life) to examine the cycling behavior of sulfur in yellow poplar (Liriodendron tulipifera), red maple (Acer rubrum), and loblolly pine (Pinus taeda) trees. Some findings pertain to methods development for estimating dry deposition of sulfur to forest canopies and the magnitude of sulfur emissions from natural sources (Task II). We will determine through field studies, the internal cycling, storage, and biogenic emission of sulfur, as traced by 35 SO 4 2- , in environments impacted by atmospheric sulfate deposition; and will determine through isotope dilution studies, the contribution of foliar leaching and dry deposition to net throughfall (NTF) sulfate concentrations beneath deciduous and coniferous trees in such environments. 3 refs., 2 figs., 1 tab

Effects of litter manipulation on litter decomposition in a successional gradients of tropical forests in southern China

DEFF Research Database (Denmark)

Chen, Hao; Gurmesa, Geshere A.; Liu, Lei

2014-01-01

Global changes such as increasing CO2, rising temperature, and land-use change are likely to drive shifts in litter inputs to forest floors, but the effects of such changes on litter decomposition remain largely unknown. We initiated a litter manipulation experiment to test the response of litter...... decomposition to litter removal/addition in three successional forests in southern China, namely masson pine forest (MPF), mixed coniferous and broadleaved forest (MF) and monsoon evergreen broadleaved forest (MEBF). Results showed that litter removal decreased litter decomposition rates by 27%, 10% and 8...

Root diseases in coniferous forests of the Inland West: potential implications of fuels treatments

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Raini C. Rippy; Jane E. Stewart; Paul J. Zambino; Ned B. Klopfenstein; Joanne M. Tirocke; Mee-Sook Kim; Walter G. Thies

2005-01-01

After nearly 100 years of fire exclusion, introduced pests, and selective harvesting, a change in forest composition has occurred in many Inland West forests of North America. This change in forest structure has frequently been accompanied by increases in root diseases and/or an unprecedented buildup of fuels. Consequently, many forest managers are implementing plans...

Mapping forest functional type in a forest-shrubland ecotone using SPOT imagery and predictive habitat distribution modelling

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Assal, Timothy J.; Anderson, Patrick J.; Sibold, Jason

2015-01-01

The availability of land cover data at local scales is an important component in forest management and monitoring efforts. Regional land cover data seldom provide detailed information needed to support local management needs. Here we present a transferable framework to model forest cover by major plant functional type using aerial photos, multi-date Système Pour l’Observation de la Terre (SPOT) imagery, and topographic variables. We developed probability of occurrence models for deciduous broad-leaved forest and needle-leaved evergreen forest using logistic regression in the southern portion of the Wyoming Basin Ecoregion. The model outputs were combined into a synthesis map depicting deciduous and coniferous forest cover type. We evaluated the models and synthesis map using a field-validated, independent data source. Results showed strong relationships between forest cover and model variables, and the synthesis map was accurate with an overall correct classification rate of 0.87 and Cohen’s kappa value of 0.81. The results suggest our method adequately captures the functional type, size, and distribution pattern of forest cover in a spatially heterogeneous landscape.

The contribution of competition to tree mortality in old-growth coniferous forests

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Das, A.; Battles, J.; Stephenson, N.L.; van Mantgem, P.J.

2011-01-01

Competition is a well-documented contributor to tree mortality in temperate forests, with numerous studies documenting a relationship between tree death and the competitive environment. Models frequently rely on competition as the only non-random mechanism affecting tree mortality. However, for mature forests, competition may cease to be the primary driver of mortality.We use a large, long-term dataset to study the importance of competition in determining tree mortality in old-growth forests on the western slope of the Sierra Nevada of California, U.S.A. We make use of the comparative spatial configuration of dead and live trees, changes in tree spatial pattern through time, and field assessments of contributors to an individual tree's death to quantify competitive effects.Competition was apparently a significant contributor to tree mortality in these forests. Trees that died tended to be in more competitive environments than trees that survived, and suppression frequently appeared as a factor contributing to mortality. On the other hand, based on spatial pattern analyses, only three of 14 plots demonstrated compelling evidence that competition was dominating mortality. Most of the rest of the plots fell within the expectation for random mortality, and three fit neither the random nor the competition model. These results suggest that while competition is often playing a significant role in tree mortality processes in these forests it only infrequently governs those processes. In addition, the field assessments indicated a substantial presence of biotic mortality agents in trees that died.While competition is almost certainly important, demographics in these forests cannot accurately be characterized without a better grasp of other mortality processes. In particular, we likely need a better understanding of biotic agents and their interactions with one another and with competition. ?? 2011.

The first fossil of a bolbitidoid fern belongs to the early-divergent lineages of Elaphoglossum (Dryopteridaceae).

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Lóriga, Josmaily; Schmidt, Alexander R; Moran, Robbin C; Feldberg, Kathrin; Schneider, Harald; Heinrichs, Jochen

2014-09-01

• Closing gaps in the fossil record and elucidating phylogenetic relationships of mostly incomplete fossils are major challenges in the reconstruction of the diversification of fern lineages through time. The cosmopolitan family Dryopteridaceae represents one of the most species-rich families of leptosporangiate ferns, yet its fossil record is sparse and poorly understood. Here, we describe a fern inclusion in Miocene Dominican amber and investigate its relationships to extant Dryopteridaceae.• The morphology of the fossil was compared with descriptions of extant ferns, resulting in it being tentatively assigned to the bolbitidoid fern genus Elaphoglossum. This assignment was confirmed by reconstructing the evolution of the morphological characters preserved in the inclusion on a molecular phylogeny of 158 extant bolbitidoid ferns. To assess the morphology-based assignment of the fossil to Elaphoglossum, we examined DNA-calibrated divergence time estimates against the age of the amber deposits from which it came.• The fossil belongs to Elaphoglossum and is the first of a bolbitidoid fern. Its assignment to a particular section of Elaphoglossum could not be determined; however, sects. Lepidoglossa, Polytrichia, and Setosa can be discounted because the fossil lacks subulate scales or scales with acicular marginal hairs. Thus, the fossil might belong to either sects. Amygdalifolia, Wrightiana, Elaphoglossum, or Squamipedia or to an extinct lineage.• The discovery of a Miocene Elaphoglossum fossil provides remarkable support to current molecular clock-based estimates of the diversification of these ferns. © 2014 Botanical Society of America, Inc.

Diversity and significance of eriophyoid mites (Acari: Eriophyoidea associated with coniferous trees in Poland: a review

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Kiedrowicz Agnieszka

2016-06-01

Full Text Available Among the approximately 200 eriophyoid mite species associated with coniferous trees worldwide, 33 species (of the families Eriophyidae and Phytoptidae infest conifers in Poland, and 24 of them can cause visible feeding symptoms. In this paper we discuss the importance of eriophyoid mites to coniferous plants in Poland and their potential impact on the decorative value of ornamental plants. We emphasize the general lack of knowledge about the diversity of eriophyoid mites associated with coniferous trees and its role in the management and control of this economically important mite group.

[Estimation of carbonaceous gases emission from forest fires in Xiao Xing'an Mountains of Northeast China in 1953-2011].

Science.gov (United States)

Hu, Hai-Qing; Luo, Bi-Zhen; Wei, Shu-Jing; Sun, Long; Wei, Shu-Wei; Wen, Zheng-Min

2013-11-01

Based on the forest resources investigation data and the forest fire inventory in 1953-2011, in combining with our field research in burned areas and our laboratory experiments, this paper estimated the carbonaceous gases carbon dioxide (CO2), carbon monoxide (CO), methane (CH4), and nonmethane hydrocarbons (NMHC) emission from the forest fires in Xiao Xing' an Mountains of Heilongjiang Province, Northeast China in 1953-2011. The total carbon emission from the forest fires in the Xiao Xing'an Mountains in 1953-2011 was 1.12 x 10(7) t, and the annual emission was averagely 1.90 x10(5) t, accounting for 1.7% of the annual average total carbon emission from the forest fires in China. The emission of CO2, CO, CH4, and NMHC was 3.39 x 10(7), 1.94 x 10(5), 1.09 x 10(5), and 7.46 x 10(4) t, respectively, and the corresponding annual average emission was 5.74 x 10(5), 3.29 x 10(4), 1.85 x 10(3), and 1.27 x 10(3) t, accounting for 1.4%, 1.2%, 1.7%, and 1.1% of the annual carbonaceous gases emitted from the forest fires in China, respectively. The combustion efficiency and the carbon emission per unit burned area of different forest types decreased in order of coniferous forest > broad-leaved forest > coniferous broadleaved mixed forest. Some rational forest fire management measures were put forward.

SURVEY OF ORNAMENTAL FERNS, THEIR MORPHOLOGY AND ...

African Journals Online (AJOL)

ornamental ferns for environmental management and economic values. ... little variations in the structures of rhizome except in Phymatodes .... forms such as erect, tall, open, bushy and .... linear leaflet with acute apex and flat, glabrous lamina.

[Temperature sensitivity of soil organic carbon mineralization and β-glucosidase enzymekinetics in the northern temperate forests at different altitudes, China].

Science.gov (United States)

Fan, Jin-juan; Li, Dan-dan; Zhang, Xin-yu; He, Nian-peng; Bu, Jin-feng; Wang, Qing; Sun, Xiao-min; Wen, Xue-fa

2016-01-01

Soil samples, which were collected from three typical forests, i.e., Betula ermanii forest, coniferous mixed broad-leaved forest, and Pinus koraiensis forest, at different altitudes along the southern slope of Laotuding Mountain of Changbai Mountain range in Liaoning Province of China, were incubated over a temperature gradient in laboratory. Soil organic carbon mineralization rates (Cmin), soil β-1,4-glucosidase (βG) kinetics and their temperature sensitivity (Q₁₀) were measured. The results showed that both altitude and temperature had significant effects on Cmin · Cmin increased with temperature and was highest in the B. ermanii forest. The temperature sensitivity of Cmin [Q₁₀(Cmin)] ranked in order of B. ermanii forest > P. koraiensis forest > coniferous mixed broad-leaved forest, but did not differ significantly among the three forests. Both the maximum activity (Vmax) and the Michaelis constant (Km) of the βG responded positively to temperature for all the forests. The temperature sensitivity of Vmax [Q₁₀(Vmax)] ranged from 1.78 to 1.90, and the temperature sensitivity of Km [Q₁₀(Km)] ranged from 1.79 to 2.00. The Q₁₀(Vmax)/Q10(Km) ratios were significantly greater in the B. ermanii soil than in the other two forest soils, suggesting that the βG kinetics-dependent impacts of the global warming or temperature increase on the decomposition of soil organic carbon were temperature sensitive for the forests at the higher altitudes.

In vitro mutagenesis of commercial fern, Asplenium nidus from spores

International Nuclear Information System (INIS)

Norazlina Noordin

2004-01-01

Asplenium is a largest, most diverse fern genera. One of the common species is Asplenium nidus, well known as Bird's-nest fern, a medium to large fern with erect, stout, unbranched rhizomes. In creating variability of ferns for the benefit of the ornamental plant industry, in vitro mutagenesis is used. In this study, spores of Asplenium nidus were collected from frond bearing mature sporangia. Spores were cultured in modified 1/2 MS basal medium supplemented with various combinations of 6-Benzylaminopurine (BAP) and Naphtalene Acetic Acid (NAA). Spore cultures were incubated in incubation room at 24 degree C with 16 hours photoperiod (3500 lux). It was found that, the most effective combinations were 1 mg/1 BAP + 0. 1 mg/1 NAA and 2mg/1 BAP + 0. 1 mg/1 NAA. Prothallus was formed after 10 days of cultures and gametophytes were formed 1 month later. These gametophytes were irradiated with Gamma ray at doses of 0, 20, 90, 120, 150 and 180 Gy. From the preliminary result obtained from this study, for generating variations and desired phenotypic expression for Asplenium nidus, recommended doses for in vitro mutagenesis using spores are between 90 Gy to 150 Gy. Gametophytes were subcultured at monthly interval to ensure further development and propagation. Frequent monitoring for any changes in the morphology of the irradiated Asplenium nidus plants were carried out. (Author)

Using Lidar and color infrared imagery to successfully measure stand characteristics on the William B. Bankhead National Forest, Alabama

Science.gov (United States)

Jeffrey Stephens; Luben Dimov; Callie Schweitzer; Wubishet Tadesse

2008-01-01

Light detection and ranging (Lidar) and color infrared imagery (CIR) were used to quantify forest structure and to distinguish deciduous from coniferous trees for selected stands on the William B. Bankhead National Forest in Alabama. Lidar bare ground and vegetation point clouds were used to determine tree heights and tree locations. Lidar accuracy was assessed by...

Conservation of biodiversity: a useful paradigm for forest ecosystem management.

Science.gov (United States)

A.B. Carey; R.O. Curtis

1996-01-01

The coniferous forests of the Western Hemlock Zone of western Oregon and western Washington are remarkable in the longevity and stature of their trees, long intervals between stand-replacing events, capacity to produce timber, diversity of life forms and species, and controversy over their management. The controversy is hardly new (Overton and Hunt 1974). But the...

Changes in soil solution chemistry of Andisols following invasion by bracken fern

Science.gov (United States)

J. L. Johnson-Maynard; P. A. McDaniel; D. E. Ferguson; A. L. Falen

1998-01-01

Disturbed areas within the Grand Fir Mosaic (GFM) ecosystem of northern Idaho show little to no natural conifer regeneration. Clear-cut sites are invaded quickly by bracken fern successional communities and seem to be in an arrested state of secondary succession. This study compared the soil solution composition of Andisols supporting bracken fern successional...

Arsenic accumulation by two brake ferns growing on an arsenic mine and their potential in phytoremediation.

Science.gov (United States)

Wei, Chao-Yang; Chen, Tong-Bin

2006-05-01

In an area near an arsenic mine in Hunan Province of south China, soils were often found with elevated arsenic levels. A field survey was conducted to determine arsenic accumulation in 8 Cretan brake ferns (Pteris cretica) and 16 Chinese brake ferns (Pteris vittata) growing on these soils. Three factors were evaluated: arsenic concentration in above ground parts (fronds), arsenic bioaccumulation factor (BF; ratio of arsenic in fronds to soil) and arsenic translocation factor (TF; ratio of arsenic in fronds to roots). Arsenic concentrations in the fronds of Chinese brake fern were 3-704 mg kg-1, the BFs were 0.06-7.43 and the TFs were 0.17-3.98, while those in Cretan brake fern were 149-694 mg kg-1, 1.34-6.62 and 1.00-2.61, respectively. Our survey showed that both ferns were capable of arsenic accumulation under field conditions. With most of the arsenic being accumulated in the fronds, these ferns have potential for use in phytoremediation of arsenic contaminated soils.

Assessment of Soil Organic Carbon Stock of Temperate Coniferous Forests in Northern Kashmir

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Davood A. Dar

2015-02-01

Full Text Available  Soil organic carbon (SOC estimation in temperate forests of the Himalaya is important to estimate their contribution to regional, national and global carbon stocks. Physico chemical properties of soil were quantified to assess soil organic carbon density (SOC and SOC CO2 mitigation density at two soil depths (0-10 and 10-20 cms under temperate forest in the Northern region of Kashmir Himalayas India. The results indicate that conductance, moisture content, organic carbon and organic matter were significantly higher while as pH and bulk density were lower at Gulmarg forest site. SOC % was ranging from 2.31± 0.96 at Gulmarg meadow site to 2.31 ± 0.26 in Gulmarg forest site. SOC stocks in these temperate forests were from 36.39 ±15.40 to 50.09 ± 15.51 Mg C ha-1. The present study reveals that natural vegetation is the main contributor of soil quality as it maintained the soil organic carbon stock. In addition, organic matter is an important indicator of soil quality and environmental parameters such as soil moisture and soil biological activity change soil carbon sequestration potential in temperate forest ecosystems.DOI: http://dx.doi.org/10.3126/ije.v4i1.12186International Journal of Environment Volume-4, Issue-1, Dec-Feb 2014/15; page: 161-178

An annotated list of the flora of the Bisley Area Luquillo Experimental Forest, Puerto Rico 1987 to 1992

Science.gov (United States)

Jesus Danilo Chinea; Renee J. Beymer; Carlos Rivera; Ines Sastre de Jeses; F.N. Scatena

1993-01-01

Known species of plants, including bryophytes and ferns, are listed for the area of the Bisley experimental watershed area, a subtropical wet forest in the Luquillo Mountains of northeastern Puerto Rico.

Glycoside Hydrolase (GH) 45 and 5 Candidate Cellulases in Aphelenchoides besseyi Isolated from Bird?s-Nest Fern

OpenAIRE

Wu, Guan-Long; Kuo, Tzu-Hao; Tsay, Tung-Tsuan; Tsai, Isheng J.; Chen, Peichen J.

2016-01-01

Five Aphelenchoides besseyi isolates collected from bird's-nest ferns or rice possess different parasitic capacities in bird's-nest fern. Two different glycoside hydrolase (GH) 45 genes were identified in the fern isolates, and only one was found in the rice isolates. A Abe GH5-1 gene containing an SCP-like family domain was found only in the fern isolates. Abe GH5-1 gene has five introns suggesting a eukaryotic origin. A maximum likelihood phylogeny revealed that Abe GH5-1 is part of the nem...

Improving winter leaf area index estimation in evergreen coniferous forests and its significance in carbon and water fluxes modeling

Science.gov (United States)

Wang, R.; Chen, J. M.; Luo, X.

2016-12-01

Modeling of carbon and water fluxes at the continental and global scales requires remotely sensed LAI as inputs. For evergreen coniferous forests (ENF), severely underestimated winter LAI has been one of the issues for mostly available remote sensing products, which could cause negative bias in the modeling of Gross Primary Productivity (GPP) and evapotranspiration (ET). Unlike deciduous trees which shed all the leaves in winter, conifers retains part of their needles and the proportion of the retained needles depends on the needle longevity. In this work, the Boreal Ecosystem Productivity Simulator (BEPS) was used to model GPP and ET at eight FLUXNET Canada ENF sites. Two sets of LAI were used as the model inputs: the 250m 10-day University of Toronto (U of T) LAI product Version 2 and the corrected LAI based on the U of T LAI product and the needle longevity of the corresponding tree species at individual sites. Validating model daily GPP (gC/m2) against site measurements, the mean RMSE over eight sites decreases from 1.85 to 1.15, and the bias changes from -0.99 to -0.19. For daily ET (mm), mean RMSE decreases from 0.63 to 0.33, and the bias changes from -0.31 to -0.16. Most of the improvements occur in the beginning and at the end of the growing season when there is large correction of LAI and meanwhile temperature is still suitable for photosynthesis and transpiration. For the dormant season, the improvement in ET simulation mostly comes from the increased interception of precipitation brought by the elevated LAI during that time. The results indicate that model performance can be improved by the application the corrected LAI. Improving the winter RS LAI can make a large impact on land surface carbon and energy budget.

Evaluating the Contribution of Climate Forcing and Forest Dynamics to Accelerating Carbon Sequestration by Forest Ecosystems in the Northeastern U.S.: Final Report

Energy Technology Data Exchange (ETDEWEB)

Munger, J. William [Harvard University, SEAS; Foster, David R. [Harvard University, Harvard Forest; Richardson, Andrew D. [Harvard University, OEB

2014-10-01

This report summarizes work to improve quantitative understanding of the terrestrial ecosystem processes that control carbon sequestration in unmanaged forests It builds upon the comprehensive long-term observations of CO2 fluxes, climate and forest structure and function at the Harvard Forest in Petersham, MA. This record includes the longest CO2 flux time series in the world. The site is a keystone for the AmeriFlux network. Project Description The project synthesizes observations made at the Harvard Forest HFEMS and Hemlock towers, which represent the dominant mixed deciduous and coniferous forest types in the northeastern United States. The 20+ year record of carbon uptake at Harvard Forest and the associated comprehensive meteorological and biometric data, comprise one of the best data sets to challenge ecosystem models on time scales spanning hourly, daily, monthly, interannual and multi-decadal intervals, as needed to understand ecosystem change and climate feedbacks.

Are rates of species diversification and body size evolution coupled in the ferns?

Science.gov (United States)

Testo, Weston L; Sundue, Michael A

2018-03-01

Understanding the relationship between phenotypic evolution and lineage diversification is a central goal of evolutionary biology. To extend our understanding of the role morphological evolution plays in the diversification of plants, we examined the relationship between leaf size evolution and lineage diversification across ferns. We tested for an association between body size evolution and lineage diversification using a comparative phylogenetic approach that combined a time-calibrated phylogeny and leaf size data set for 2654 fern species. Rates of leaf size change and lineage diversification were estimated using BAMM, and rate correlations were performed for rates obtained for all families and individual species. Rates and patterns of rate-rate correlation were also analyzed separately for terrestrial and epiphytic taxa. We find no significant correlation between rates of leaf area change and lineage diversification, nor was there a difference in this pattern when growth habit is considered. Our results are consistent with the findings of an earlier study that reported decoupled rates of body size evolution and diversification in the Polypodiaceae, but conflict with a recent study that reported a positive correlation between body size evolution and lineage diversification rates in the tree fern family Cyatheaceae. Our findings indicate that lineage diversification in ferns is largely decoupled from shifts in body size, in contrast to several other groups of organisms. Speciation in ferns appears to be primarily driven by hybridization and isolation along elevational gradients, rather than adaptive radiations featuring prominent morphological restructuring. The exceptional diversity of leaf morphologies in ferns appears to reflect a combination of ecophysiological constraints and adaptations that are not key innovations. © 2018 Botanical Society of America.

Moving water well: comparing hydraulic efficiency in twigs and trunks of coniferous, ring-porous, and diffuse-porous saplings from temperate and tropical forests

Science.gov (United States)

Katherine McCulloh; John S. Sperry; Barbara Lachenbruch; Frederick D. Meinzer; Peter B. Reich; Steven Voelker

2010-01-01

Coniferous, diffuse-porous and ring-porous trees vary in their xylem anatomy, but the functional consequences of these differences are not well understood from the scale of the conduit to the individual. Hydraulic and anatomical measurements were made on branches and trunks from 16 species from temperate and tropical areas, representing all three wood types. Scaling of...

Management of western coniferous forest habitat for nesting accipiter hawks

Science.gov (United States)

Richard T. Reynolds

1983-01-01

Availability of nesting sites can limit accipiter populations. Because accipiters nest in dense forest stands, any alteration that opens these stands is likely to lessen their desirability as nest sites. Tree growth and the associated changes in the vegetative structure of aging nest sites limit the number of years sites will be suitable. Therefore, prospective...

Ecological anatomy of ferns fronds

Directory of Open Access Journals (Sweden)

Nina M. Derzhavina

2014-04-01

Full Text Available Structural types of frond anatomy are distinguished on the basis of investigation of 30 species of homosporous ferns and with regard for literature: hydromorphic, hygromorphic, mesomorphic, subxeromorphic, and subsucculent (cryptic succulent. Following frond traits are of highest adaptive value: their area and thickness, type of mesophyll, dry weight of an area unit – specific superficial density, cellular volume, and number of cells per unit of frond area.

Zoning of the Russian Federation territory based on forest management and forest use intensity

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A. A. Маrtynyuk

2016-02-01

Full Text Available Over extended periods issues of forest management intensification are important in all aspects of Russian forest sector development. Sufficient research has been done in silviculture, forest planning and forest economics to address forest management intensification targets. Systems of our national territory forest management and forest economics zoning due to specifics of timber processing and forest area infrastructure have been developed. Despite sufficient available experience in sustainable forest management so far intensification issues were addressed due to development of new woodlands without proper consideration of forest regeneration and sustainable forest management operations. It resulted in forest resource depletion and unfavorable substitution of coniferous forests with less valuable softwood ones in considerable territories (especially accessible for transport. The situation is complicated since degree of forest ecosystem changes is higher in territories with high potential productivity. Ongoing changes combined with the present effective forest management system resulted in a situation where development of new woodlands is impossible without heavy investments in road construction; meanwhile road construction is unfeasible due to distances to timber processing facilities. In the meantime, changes in forest legislation, availability of forest lease holding, and promising post-logging forest regeneration technologies generate new opportunities to increase timber volumes due to application of other procedures practically excluding development of virgin woodlands. With regard to above, the Russian territory was zoned on a basis of key factors that define forest management and forest use intensification based on forest ecosystem potential productivity and area transport accessibility. Based on available data with GIS analysis approach (taking into consideration value of various factors the Russian Federation forest resources have been

A three-dimensional stochastic model of the behavior of radionuclides in forests. Part 2. Cs-137 behavior in forest soils

International Nuclear Information System (INIS)

Berg, Mitchell T.; Shuman, Larry J.

1995-01-01

Using a three-dimensional stochastic model of radionuclides in forests developed in Part 1, this work simulates the long-term behavior of Cs-137 in forest soil. It is assumed that the behavior of Cs-137 in soils is driven by its advection and dispersion due to the infiltration of the soil solution, and its sorption to the soil matrix. As Cs-137 transport through soils is affected by its uptake and release by forest vegetation, a model of radiocesium behavior in forest vegetation is presented in Part 3 of this paper. To estimate the rate of infiltration of water through the soil, models are presented to estimate the hydrological cycle of the forest including infiltration, evapotranspiration, and the root uptake of water. The state transition probabilities for the random walk model of Cs-137 transport are then estimated using the models developed to predict the distribution of water in the forest. The random walk model is then tested using a base line scenario in which Cs-137 is deposited into a coniferous forest ecosystem

Dynamics of radiation damage and repair processes in coniferous stands in a 10-km region of the Chernobyl nuclear power station

International Nuclear Information System (INIS)

Kozubov, G.M.; Taskaev, A.I.

1995-01-01

Properties of morphogenesis, growth dynamics, anatomy and ultrastructure of wood and needle, reproductive processes in coniferous plants were studied under different level of radiation effect in the 10-km zone in 1986-1992. It was established that the full drying of pine forests began under absorbed dose 80-100 Gy/year. Threshold doses, after which repair processes were possible, reached to 10-12 Gy/year for Picea abies and 50 Gy/year for Pinus sylvestris. Three maine stages are revealed in dynamics of radiation damage and repair processes in studied conifers and their morphological and functional characteristic is presented. 14 refs., 3 figs., 2 tabs

Project "Conservation, Restoration, and Development of the Juan Fernández islands, Chile" Proyecto conservación, restauración y desarrollo de las islas Juan Fernández, Chile

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JAIME G. CUEVAS

2001-12-01

Full Text Available From a scientific point of view, the Juan Fernández islands contain one of the most interesting floras of the planet. Although protected as a National Park and a World Biosphere Reserve, 400 years of human interference have left deep traces in the native plant communities. Repeated burning, overexploitation of species, and the introduction of animal and plant plagues have taken 75 % of the endemic vascular flora to the verge of extinction. In 1997, Chile's national forest service (Corporación Nacional Forestal, CONAF started an ambitious project, whose objective is the recovery of this highly complex ecosystem with a socio-ecological focus. Juan Fernández makes an interesting case, as the local people (600 persons practically live within the park, therefore impeding the exclusion of the people from any conservation program. Secondly, the relatively small size of the archipelago (100 km² permits the observation of the effects of whatever modification in the ecosystem on small scales in time and space. Thirdly, the native and introduced biota are interrelated in such a way that human-caused changes in one species population may provoke unexpected results amongst other, non-target species. The project mainly deals with the eradication or control of some animal and plant plagues, the active conservation and restoration of the flora and the inclusion of the local people in conservation planning. This article presents the park's general problems, the strategy proposed to resolve them as well as some preliminary results. This project shows the complexity of the conservation activities in practice, with diverse and complex interrelations and gaps in ecological knowledge. In this respect, the project may well serve as a model for similar programs in other placesLas islas Juan Fernández albergan una de las floras más interesantes del planeta desde el punto de vista científico. Aunque están protegidas como Parque Nacional y Reserva Mundial de la

Phylogeny of Marsileaceous Ferns and Relationships of the Fossil Hydropteris pinnata Reconsidered.

Science.gov (United States)

Pryer

1999-09-01

Recent phylogenetic studies have provided compelling evidence that confirms the once disputed hypothesis of monophyly for heterosporous leptosporangiate ferns (Marsileaceae and Salviniaceae). Hypotheses for relationships among the three genera of Marsileaceae (Marsilea, Regnellidium, and Pilularia), however, have continued to be in conflict. The phylogeny of Marsileaceae is investigated here using information from morphology and rbcL sequence data. In addition, relationships among all heterosporous ferns, including the whole-plant fossil Hydropteris pinnata are reconsidered. Data sets of 71 morphological and 1239 rbcL characters for 23 leptosporangiate ferns, including eight heterosporous ingroup taxa and 15 homosporous outgroup taxa, were subjected to maximum parsimony analysis. Morphological analyses were carried out both with and without the fossil Hydropteris, and it was excluded from all analyses with rbcL data. An annotated list of the 71 morphological characters is provided in the appendix. For comparative purposes, the Rothwell and Stockey (1994) data set was also reanalyzed here. The best estimate of phylogenetic relationships for Marsileaceae in all analyses is that Pilularia and Regnellidium are sister taxa and Marsilea is sister to that clade. Morphological synapomorphies for various nodes are discussed. Analyses that included Hydropteris resulted in two most-parsimonious trees that differ only in the placement of the fossil. One topology is identical to the relationship found by Rothwell and Stockey (1994), placing the fossil sister to the Azolla plus Salvinia clade. The alternative topology places Hydropteris as the most basal member of the heterosporous fern clade. Equivocal interpretations for character evolution in heterosporous ferns are discussed in the context of these two most-parsimonious trees. Because of the observed degree of character ambiguity, the phylogenetic placement of Hydropteris is best viewed as unresolved, and recognition of the

FERN - a Java framework for stochastic simulation and evaluation of reaction networks.

Science.gov (United States)

Erhard, Florian; Friedel, Caroline C; Zimmer, Ralf

2008-08-29

Stochastic simulation can be used to illustrate the development of biological systems over time and the stochastic nature of these processes. Currently available programs for stochastic simulation, however, are limited in that they either a) do not provide the most efficient simulation algorithms and are difficult to extend, b) cannot be easily integrated into other applications or c) do not allow to monitor and intervene during the simulation process in an easy and intuitive way. Thus, in order to use stochastic simulation in innovative high-level modeling and analysis approaches more flexible tools are necessary. In this article, we present FERN (Framework for Evaluation of Reaction Networks), a Java framework for the efficient simulation of chemical reaction networks. FERN is subdivided into three layers for network representation, simulation and visualization of the simulation results each of which can be easily extended. It provides efficient and accurate state-of-the-art stochastic simulation algorithms for well-mixed chemical systems and a powerful observer system, which makes it possible to track and control the simulation progress on every level. To illustrate how FERN can be easily integrated into other systems biology applications, plugins to Cytoscape and CellDesigner are included. These plugins make it possible to run simulations and to observe the simulation progress in a reaction network in real-time from within the Cytoscape or CellDesigner environment. FERN addresses shortcomings of currently available stochastic simulation programs in several ways. First, it provides a broad range of efficient and accurate algorithms both for exact and approximate stochastic simulation and a simple interface for extending to new algorithms. FERN's implementations are considerably faster than the C implementations of gillespie2 or the Java implementations of ISBJava. Second, it can be used in a straightforward way both as a stand-alone program and within new

Development of Forest Drought Index and Forest Water Use Prediction in Gyeonggi Province, Korea Using High-Resolution Weather Research and Forecast Data and Localized JULES Land Surface Model

Science.gov (United States)

Lee, H.; Park, J.; Cho, S.; Lee, S. J.; Kim, H. S.

2017-12-01

Forest determines the amount of water available to low land ecosystems, which use the rest of water after evapotranspiration by forests. Substantial increase of drought, especially for seasonal drought, has occurred in Korea due to climate change, recently. To cope with this increasing crisis, it is necessary to predict the water use of forest. In our study, forest water use in the Gyeonggi Province in Korea was estimated using high-resolution (spatial and temporal) meteorological forecast data and localized Joint UK Land Environment Simulator (JULES) which is one of the widely used land surface models. The modeled estimation was used for developing forest drought index. The localization of the model was conducted by 1) refining the existing two tree plant functional types (coniferous and deciduous trees) into five (Quercus spp., other deciduous tree spp., Pinus spp., Larix spp., and other coniferous spp.), 2) correcting moderate resolution imaging spectroradiometer (MODIS) leaf area index (LAI) through data assimilation with in situ measured LAI, and 3) optimizing the unmeasured plant physiological parameters (e.g. leaf nitrogen contents, nitrogen distribution within canopy, light use efficiency) based on sensitivity analysis of model output values. The high-resolution (hourly and 810 × 810 m) National Center for AgroMeteorology-Land-Atmosphere Modeling Package (NCAM-LAMP) data were employed as meteorological input data in JULES. The plant functional types and soil texture of each grid cell in the same resolution with that of NCAM-LAMP was also used. The performance of the localized model in estimating forest water use was verified by comparison with the multi-year sapflow measurements and Eddy covariance data of Taehwa Mountain site. Our result can be used as referential information to estimate the forest water use change by the climate change. Moreover, the drought index can be used to foresee the drought condition and prepare to it.

A Gompertz regression model for fern spores germination

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Gabriel y Galán, Jose María

2015-06-01

Full Text Available Germination is one of the most important biological processes for both seed and spore plants, also for fungi. At present, mathematical models of germination have been developed in fungi, bryophytes and several plant species. However, ferns are the only group whose germination has never been modelled. In this work we develop a regression model of the germination of fern spores. We have found that for Blechnum serrulatum, Blechnum yungense, Cheilanthes pilosa, Niphidium macbridei and Polypodium feuillei species the Gompertz growth model describe satisfactorily cumulative germination. An important result is that regression parameters are independent of fern species and the model is not affected by intraspecific variation. Our results show that the Gompertz curve represents a general germination model for all the non-green spore leptosporangiate ferns, including in the paper a discussion about the physiological and ecological meaning of the model.La germinación es uno de los procesos biológicos más relevantes tanto para las plantas con esporas, como para las plantas con semillas y los hongos. Hasta el momento, se han desarrollado modelos de germinación para hongos, briofitos y diversas especies de espermatófitos. Los helechos son el único grupo de plantas cuya germinación nunca ha sido modelizada. En este trabajo se desarrolla un modelo de regresión para explicar la germinación de las esporas de helechos. Observamos que para las especies Blechnum serrulatum, Blechnum yungense, Cheilanthes pilosa, Niphidium macbridei y Polypodium feuillei el modelo de crecimiento de Gompertz describe satisfactoriamente la germinación acumulativa. Un importante resultado es que los parámetros de la regresión son independientes de la especie y que el modelo no está afectado por variación intraespecífica. Por lo tanto, los resultados del trabajo muestran que la curva de Gompertz puede representar un modelo general para todos los helechos leptosporangiados

Estimates of ion sources in deciduous and coniferous throughfall

Science.gov (United States)

Puckett, L.J.

1990-01-01

Estimates of external and internal sources of ions in net throughfall deposition were derived for a deciduous and coniferous canopy by use of multiple regression. The externel source component appears to be dominated by dry deposition of Ca2+, SO2 and NO3- during dormant and growing seasons for the two canopy types. Increases in the leaching rates of K+ and Mg2+ during the growing season reflect the presence of leaves in the deciduous canopy and increased physiological activity in both canopies. Internal leaching rates for SO42- doubled during the growing season presumably caused by increased physiological activity and uptake of SO2 through stomates. Net deposition of SO42- in throughfall during the growing season appears highly dependent on stomatal uptake of SO2. Estimates of SO2 deposition velocities were 0.06 cm s-1 and 0.13 cm s-1 for the deciduous and coniferous canopies, respectively, during the dormant season, and 0.30 cm s-1 and 0.43 cm s-1 for the deciduous and coniferous canopies, respectively, during the growing season. For the ions of major interest with respect to ecosystem effects, namely H+, NO3- and SO42-, precipitation inputs generally outweighed estimates of dry deposition input. However, net throughfall deposition of NO3- and SO42- accounted for 20-47 and 34-50 per cent, respectively, of total deposition of those ions. Error estimates of ion sources were at least 50-100 per cent and the method is subject to several assumptions and limitations.

Global-Scale Patterns of Forest Fragmentation

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Kurt Riitters

2000-12-01

Full Text Available We report an analysis of forest fragmentation based on 1-km resolution land-cover maps for the globe. Measurements in analysis windows from 81 km 2 (9 x 9 pixels, "small" scale to 59,049 km 2 (243 x 243 pixels, "large" scale were used to characterize the fragmentation around each forested pixel. We identified six categories of fragmentation (interior, perforated, edge, transitional, patch, and undetermined from the amount of forest and its occurrence as adjacent forest pixels. Interior forest exists only at relatively small scales; at larger scales, forests are dominated by edge and patch conditions. At the smallest scale, there were significant differences in fragmentation among continents; within continents, there were significant differences among individual forest types. Tropical rain forest fragmentation was most severe in North America and least severe in Europe-Asia. Forest types with a high percentage of perforated conditions were mainly in North America (five types and Europe-Asia (four types, in both temperate and subtropical regions. Transitional and patch conditions were most common in 11 forest types, of which only a few would be considered as "naturally patchy" (e.g., dry woodland. The five forest types with the highest percentage of interior conditions were in North America; in decreasing order, they were cool rain forest, coniferous, conifer boreal, cool mixed, and cool broadleaf.

Global-scale patterns of forest fragmentation

Science.gov (United States)

Riitters, K.; Wickham, J.; O'Neill, R.; Jones, B.; Smith, E.

2000-01-01

We report an analysis of forest fragmentation based on 1-km resolution land-cover maps for the globe. Measurements in analysis windows from 81 km 2 (9 ?? 9 pixels, "small" scale) to 59,049 km 2 (243 ?? 243 pixels, "large" scale) were used to characterize the fragmentation around each forested pixel. We identified six categories of fragmentation (interior, perforated, edge, transitional, patch, and undetermined) from the amount of forest and its occurrence as adjacent forest pixels. Interior forest exists only at relatively small scales; at larger scales, forests are dominated by edge and patch conditions. At the smallest scale, there were significant differences in fragmentation among continents; within continents, there were significant differences among individual forest types. Tropical rain forest fragmentation was most severe in North America and least severe in Europe - Asia. Forest types with a high percentage of perforated conditions were mainly in North America (five types) and Europe - Asia (four types), in both temperate and subtropical regions. Transitional and patch conditions were most common in 11 forest types, of which only a few would be considered as "naturally patchy" (e.g., dry woodland). The five forest types with the highest percentage of interior conditions were in North America; in decreasing order, they were cool rain forest, coniferous, conifer boreal, cool mixed, and cool broadleaf. Copyright ?? 2000 by The Resilience Alliance.

Evolution of the rpoB-psbZ region in fern plastid genomes: notable structural rearrangements and highly variable intergenic spacers.

Science.gov (United States)

Gao, Lei; Zhou, Yuan; Wang, Zhi-Wei; Su, Ying-Juan; Wang, Ting

2011-04-13

The rpoB-psbZ (BZ) region of some fern plastid genomes (plastomes) has been noted to go through considerable genomic changes. Unraveling its evolutionary dynamics across all fern lineages will lead to clarify the fundamental process shaping fern plastome structure and organization. A total of 24 fern BZ sequences were investigated with taxon sampling covering all the extant fern orders. We found that: (i) a tree fern Plagiogyria japonica contained a novel gene order that can be generated from either the ancestral Angiopteris type or the derived Adiantum type via a single inversion; (ii) the trnY-trnE intergenic spacer (IGS) of the filmy fern Vandenboschia radicans was expanded 3-fold due to the tandem 27-bp repeats which showed strong sequence similarity with the anticodon domain of trnY; (iii) the trnY-trnE IGSs of two horsetail ferns Equisetum ramosissimum and E. arvense underwent an unprecedented 5-kb long expansion, more than a quarter of which was consisted of a single type of direct repeats also relevant to the trnY anticodon domain; and (iv) ycf66 has independently lost at least four times in ferns. Our results provided fresh insights into the evolutionary process of fern BZ regions. The intermediate BZ gene order was not detected, supporting that the Adiantum type was generated by two inversions occurring in pairs. The occurrence of Vandenboschia 27-bp repeats represents the first evidence of partial tRNA gene duplication in fern plastomes. Repeats potentially forming a stem-loop structure play major roles in the expansion of the trnY-trnE IGS.

Evolution of the rpoB-psbZ region in fern plastid genomes: notable structural rearrangements and highly variable intergenic spacers

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Su Ying-Juan

2011-04-01

Full Text Available Abstract Background The rpoB-psbZ (BZ region of some fern plastid genomes (plastomes has been noted to go through considerable genomic changes. Unraveling its evolutionary dynamics across all fern lineages will lead to clarify the fundamental process shaping fern plastome structure and organization. Results A total of 24 fern BZ sequences were investigated with taxon sampling covering all the extant fern orders. We found that: (i a tree fern Plagiogyria japonica contained a novel gene order that can be generated from either the ancestral Angiopteris type or the derived Adiantum type via a single inversion; (ii the trnY-trnE intergenic spacer (IGS of the filmy fern Vandenboschia radicans was expanded 3-fold due to the tandem 27-bp repeats which showed strong sequence similarity with the anticodon domain of trnY; (iii the trnY-trnE IGSs of two horsetail ferns Equisetum ramosissimum and E. arvense underwent an unprecedented 5-kb long expansion, more than a quarter of which was consisted of a single type of direct repeats also relevant to the trnY anticodon domain; and (iv ycf66 has independently lost at least four times in ferns. Conclusions Our results provided fresh insights into the evolutionary process of fern BZ regions. The intermediate BZ gene order was not detected, supporting that the Adiantum type was generated by two inversions occurring in pairs. The occurrence of Vandenboschia 27-bp repeats represents the first evidence of partial tRNA gene duplication in fern plastomes. Repeats potentially forming a stem-loop structure play major roles in the expansion of the trnY-trnE IGS.

Root-associated fungal communities in three Pyroleae species and their mycobiont sharing with surrounding trees in subalpine coniferous forests on Mount Fuji, Japan.

Science.gov (United States)

Jia, Shuzheng; Nakano, Takashi; Hattori, Masahira; Nara, Kazuhide

2017-11-01

Pyroleae species are perennial understory shrubs, many of which are partial mycoheterotrophs. Most fungi colonizing Pyroleae roots are ectomycorrhizal (ECM) and share common mycobionts with their Pyroleae hosts. However, such mycobiont sharing has neither been examined in depth before nor has the interspecific variation in sharing among Pyroleae species. Here, we examined root-associated fungal communities in three co-existing Pyroleae species, including Pyrola alpina, Pyrola incarnata, and Orthilia secunda, with reference to co-existing ECM fungi on the surrounding trees in the same soil blocks in subalpine coniferous forests. We identified 42, 75, and 18 fungal molecular operational taxonomic units in P. alpina, P. incarnata, and O. secunda roots, respectively. Mycobiont sharing with surrounding trees, which was defined as the occurrence of the same mycobiont between Pyroleae and surrounding trees in each soil block, was most frequent among P. incarnata (31 of 44 plants). In P. alpina, sharing was confirmed in 12 of 37 plants, and the fungal community was similar to that of P. incarnata. Mycobiont sharing was least common in O. secunda, found in only 5 of 32 plants. Root-associated fungi of O. secunda were dominated by Wilcoxina species, which were absent from the surrounding ECM roots in the same soil blocks. These results indicate that mycobiont sharing with surrounding trees does not equally occur among Pyroleae plants, some of which may develop independent mycorrhizal associations with ECM fungi, as suggested in O. secunda at our research sites.

Forest biomass variation in Southernmost Brazil: the impact of Araucaria trees.

Science.gov (United States)

Rosenfield, Milena Fermina; Souza, Alexandre F

2014-03-01

A variety of environmental and biotic factors determine vegetation growth and affect plant biomass accumulation. From temperature to species composition, aboveground biomass storage in forest ecosystems is influenced by a number of variables and usually presents a high spatial variability. With this focus, the aim of the study was to evaluate the variables affecting live aboveground forest biomass (AGB) in Subtropical Moist Forests of Southern Brazil, and to analyze the spatial distribution of biomass estimates. Data from a forest inventory performed in the State of Rio Grande do Sul, Southern Brazil, was used in the present study. Thirty-eight 1-ha plots were sampled and all trees with DBH > or = 9.5cm were included for biomass estimation. Values for aboveground biomass were obtained using published allometric equations. Environmental and biotic variables (elevation, rainfall, temperature, soils, stem density and species diversity) were obtained from the literature or calculated from the dataset. For the total dataset, mean AGB was 195.2 Mg/ha. Estimates differed between Broadleaf and Mixed Coniferous-Broadleaf forests: mean AGB was lower in Broadleaf Forests (AGB(BF)=118.9 Mg/ha) when compared to Mixed Forests (AGB(MF)=250.3 Mg/ha). There was a high spatial and local variability in our dataset, even within forest types. This condition is normal in tropical forests and is usually attributed to the presence of large trees. The explanatory multiple regressions were influenced mainly by elevation and explained 50.7% of the variation in AGB. Stem density, diversity and organic matter also influenced biomass variation. The results from our study showed a positive relationship between aboveground biomass and elevation. Therefore, higher values of AGB are located at higher elevations and subjected to cooler temperatures and wetter climate. There seems to be an important contribution of the coniferous species Araucaria angustifolia in Mixed Forest plots, as it presented

Lidar-derived canopy architecture predicts Brown Creeper occupancy of two western coniferous forests

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Jody C. Vogeler; Andrew T. Hudak; Lee A. Vierling; Kerri T. Vierling

2013-01-01

In western conifer-dominated forests where the abundance of old-growth stands is decreasing, species such as the Brown Creeper (Certhia americana) may be useful as indicator species for monitoring the health of old-growth systems because they are strongly associated with habitat characteristics associated with old growth and are especially sensitive to forest...

Ferns: the missing link in shoot evolution and development

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Andrew Robert George Plackett

2015-11-01

Full Text Available Shoot development in land plants is a remarkably complex process that gives rise to an extreme diversity of forms. Our current understanding of shoot developmental mechanisms comes almost entirely from studies of angiosperms (flowering plants, the most recently diverged plant lineage. Shoot development in angiosperms is based around a layered multicellular apical meristem that produces lateral organs and/or secondary meristems from populations of founder cells at its periphery. In contrast, non-seed plant shoots develop from either single apical initials or from a small population of morphologically distinct apical cells. Although developmental and molecular information is becoming available for non-flowering plants, such as the model moss Physcomitrella patens, making valid comparisons between highly divergent lineages is extremely challenging. As sister group to the seed plants, the monilophytes (ferns and relatives represent an excellent phylogenetic midpoint of comparison for unlocking the evolution of shoot developmental mechanisms, and recent technical advances have finally made transgenic analysis possible in the emerging model fern Ceratopteris richardii. This review compares and contrasts our current understanding of shoot development in different land plant lineages with the aim of highlighting the potential role that the fern C. richardii could play in shedding light on the evolution of underlying genetic regulatory mechanisms.

Notes on the scholarly trajectory of Mª. Dolores Fernández-Posse

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Gilman, Antonio

2007-12-01

Full Text Available The scholarly trajectory of Mª Dolores Fernández- Posse involved an ongoing process of critical observation, reflection, and change that is quite rare in Archaeology. Her change from normativism to a historically informed functionalism is representative of the general evolution of Spanish archaeological studies over the course of the past thirty years. What is unusual about Fernández-Posse -and attests to her straightforward and unassuming intelligence- is that she herself changed her mind and voiced that change with clarity and humor.

La trayectoria científica de Mª Dolores Fernández-Posse se caracterizó por un proceso continuo de observación crítica, reflexión y cambio, algo poco común en Arqueología. Su cambio del normativismo a un funcionalismo de orientación histórica es representativo de la evolución de los estudios arqueológicos en España a lo largo de los últimos treinta años. Lo realmente inusual de Fernández-Posse -y lo que atestigua su directa pero no pretenciosa inteligencia- es que ella misma cambió de ideas y publicitó ese cambio con claridad y humor.

Colonisation of epiphytic ferns by skinks and geckos in the high canopy of a Bornean rainforest

OpenAIRE

Donald, J.; Clegg, J.; Ellwood, M. D. F.

2017-01-01

Nest site availability limits the fitness and survival of skinks and geckos, particularly in the canopy of tall tropical rainforests. We document the systematic colonisation and nest use of epiphytic bird’s nest ferns (Asplenium spp) by the gecko Hemiphyllodactylus typus and the skink Lipinia cf. vittigera. As part of a controlled experiment we placed 32 ferns of similar sizes in the high canopy of a lowland dipterocarp rainforest in Sabah, Malaysian Borneo. Half of these ferns, sampled after...

Phylogenetic Relationships of the Fern Cyrtomium falcatum (Dryopteridaceae from Dokdo Island Based on Chloroplast Genome Sequencing

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Gurusamy Raman

2016-12-01

Full Text Available Cyrtomium falcatum is a popular ornamental fern cultivated worldwide. Native to the Korean Peninsula, Japan, and Dokdo Island in the Sea of Japan, it is the only fern present on Dokdo Island. We isolated and characterized the chloroplast (cp genome of C. falcatum, and compared it with those of closely related species. The genes trnV-GAC and trnV-GAU were found to be present within the cp genome of C. falcatum, whereas trnP-GGG and rpl21 were lacking. Moreover, cp genomes of Cyrtomium devexiscapulae and Adiantum capillus-veneris lack trnP-GGG and rpl21, suggesting these are not conserved among angiosperm cp genomes. The deletion of trnR-UCG, trnR-CCG, and trnSeC in the cp genomes of C. falcatum and other eupolypod ferns indicates these genes are restricted to tree ferns, non-core leptosporangiates, and basal ferns. The C. falcatum cp genome also encoded ndhF and rps7, with GUG start codons that were only conserved in polypod ferns, and it shares two significant inversions with other ferns, including a minor inversion of the trnD-GUC region and an approximate 3 kb inversion of the trnG-trnT region. Phylogenetic analyses showed that Equisetum was found to be a sister clade to Psilotales-Ophioglossales with a 100% bootstrap (BS value. The sister relationship between Pteridaceae and eupolypods was also strongly supported by a 100% BS, but Bayesian molecular clock analyses suggested that C. falcatum diversified in the mid-Paleogene period (45.15 ± 4.93 million years ago and might have moved from Eurasia to Dokdo Island.

Tree ferns: monophyletic groups and their relationships as revealed by four protein-coding plastid loci.

Science.gov (United States)

Korall, Petra; Pryer, Kathleen M; Metzgar, Jordan S; Schneider, Harald; Conant, David S

2006-06-01

Tree ferns are a well-established clade within leptosporangiate ferns. Most of the 600 species (in seven families and 13 genera) are arborescent, but considerable morphological variability exists, spanning the giant scaly tree ferns (Cyatheaceae), the low, erect plants (Plagiogyriaceae), and the diminutive endemics of the Guayana Highlands (Hymenophyllopsidaceae). In this study, we investigate phylogenetic relationships within tree ferns based on analyses of four protein-coding, plastid loci (atpA, atpB, rbcL, and rps4). Our results reveal four well-supported clades, with genera of Dicksoniaceae (sensu ) interspersed among them: (A) (Loxomataceae, (Culcita, Plagiogyriaceae)), (B) (Calochlaena, (Dicksonia, Lophosoriaceae)), (C) Cibotium, and (D) Cyatheaceae, with Hymenophyllopsidaceae nested within. How these four groups are related to one other, to Thyrsopteris, or to Metaxyaceae is weakly supported. Our results show that Dicksoniaceae and Cyatheaceae, as currently recognised, are not monophyletic and new circumscriptions for these families are needed.

Unique expression of a sporophytic character on the gametophytes of notholaenid ferns (Pteridaceae).

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Johnson, Anne K; Rothfels, Carl J; Windham, Michael D; Pryer, Kathleen M

2012-06-01

Not all ferns grow in moist, shaded habitats; some lineages thrive in exposed, seasonally dry environments. Notholaenids are a clade of xeric-adapted ferns commonly characterized by the presence of a waxy exudate, called farina, on the undersides of their leaves. Although some other lineages of cheilanthoid ferns also have farinose sporophytes, previous studies suggested that notholaenids are unique in also producing farina on their gametophytes. For this reason, consistent farina expression across life cycle phases has been proposed as a potential synapomorphy for the genus Notholaena. Recent phylogenetic studies have shown two species with nonfarinose sporophytes to be nested within Notholaena, with a third nonfarinose species well supported as sister to all other notholaenids. This finding raises the question: are the gametophytes of these three species farinose like those of their close relatives, or are they glabrous, consistent with their sporophytes? We sowed spores of a diversity of cheilanthoid ferns onto culture media to observe and document whether their gametophytes produced farina. To place these species within a phylogenetic context, we extracted genomic DNA, then amplified and sequenced three plastid loci. The aligned data were analyzed using maximum likelihood to generate a phylogenetic tree. Here we show that notholaenids lacking sporophytic farina also lack farina in the gametophytic phase, and notholaenids with sporophytic farina always display gametophytic farina (with a single exception). Outgroup taxa never displayed gametophytic farina, regardless of whether they displayed farina on their sporophytes. Notholaenids are unique among ferns in consistently expressing farina across both phases of the life cycle.

Uptake of rare earth elements by dryopteris erythrosora (autumn fern)

International Nuclear Information System (INIS)

Ozaki, Takuo; Enomoto, Shuichi

2001-01-01

Mechanisms of uptake of rare earth elements (REEs) were investigated, particularly those by REE accumulator species (autumn fern). Rare earth elements are practically insoluble under natural conditions, suggesting some unknown mechanisms in REE accumulator species. In the present investigation, two notable phenomena were observed. (1) Concerning the ionic-radius dependence of REE uptake by leaves, nonaccumulator species showed an extremely high uptake for Y compared with the adjacent-ionic-radius REEs in the multitracer, while accumulator species showed no anomaly. (2) REE uptake by autumn fern was influenced by the addition of chelating chemical reagents in the uptake solution, while no effect was observed for nonaccumulator species. (author)

Environmental measures in forest. Realistic measures for counteracting negative effects of acid precipitation in forest; Miljoetiltak i skog. Realistiske tiltak for aa motvirke negative effekter av sur nedboer i skog

Energy Technology Data Exchange (ETDEWEB)

Nilsen, P [Norsk Inst. for Skogforskning, Aas (Norway)

1996-01-01

The conference paper deals with an Norwegian research programme concerning environmental measures for decreasing the effects of acidification in forest areas. This programme, which lasts in a period of five years, will terminate in 1997. An important part of the programme has been to investigate other types of measures than the ordinary methods of liming and fertilizing. In the course of the programme, there was determined to put the attention to the increased use of broad-leaved trees as an alternative in a coniferous forest. 19 refs., 1 fig.

Plant component features of forest-bog ecotones of eutrophic paludification in the south of boreal forest zone of West Siberia

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Klimova, N. V.; Chernova, N. A.; Pologova, N. N.

2018-03-01

Paludified forests formed in transitional forest-bog zone aren’t studied enough, inspite of its high expected diversity and large areas in the south of boreal forest zone of West Siberia. In this article wet birch (Betula pubescens) forests of forest-bog ecotones of eutrophic paludification are investigated on Vasyugan plain with nutrient-rich calcareous clays as soil-forming rocks. Species diversity and ecocoenotic structure of these phytocoenoses are discussed. They correlated with wetness and nutrient-availability of habitats evaluated with indicator values of plants. The participation of hydrophylous species is increasing as wetness of habitats increasing in the forest-to-bog direction like in mesotrophic paludification series. However the number of species is higher in the phytocoenoses of eutrophic paludification. The share of species required to nutrient availability is also higher, both in number and in abundance. A lot of these species are usual for eutrophic boreal forested swamps with groundwater input and absent in forests of mesotrophic paludification. Accordingly the nutrient-availability of habitats is also higher. All these features we connect with birch to be a forest forming species instead of dark-coniferous and with the influence of nutrient-rich parent rocks, which is evident in forest-bog ecotones of Vasyugan plain gradually decreasing together with peat horizon thickening.

Responses of the Carbon Storage and Sequestration Potential of Forest Vegetation to Temperature Increases in Yunnan Province, SW China

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Ruiwu Zhou

2018-04-01

Full Text Available The distribution of forest vegetation and forest carbon sequestration potential are significantly influenced by climate change. In this study, a map of the current distribution of vegetation in Yunnan Province was compiled based on data from remote sensing imagery from the Advanced Land Observing Satellite (ALOS from 2008 to 2011. A classification and regression tree (CART model was used to predict the potential distribution of the main forest vegetation types in Yunnan Province and estimate the changes in carbon storage and carbon sequestration potential (CSP in response to increasing temperature. The results show that the current total forest area in Yunnan Province is 1.86 × 107 ha and that forest covers 48.63% of the area. As the temperature increases, the area of forest distribution first increases and then decreases, and it decreases by 11% when the temperature increases from 1.5 to 2 °C. The mean carbon density of the seven types of forest vegetation in Yunnan Province is 84.69 Mg/ha. The total carbon storage of the current forest vegetation in Yunnan Province is 871.14 TgC, and the CSP is 1100.61 TgC. The largest CSP (1114.82 TgC occurs when the temperature increases by 0.5 °C. Incremental warming of 2 °C will sharply decrease the forest CSP, especially in those regions with mature coniferous forest vegetation. Semi-humid evergreen broad-leaved forests were highly sensitive to temperature changes, and the CSP of these forests will decrease with increasing temperature. Warm-hot coniferous forests have the greatest CSP in all simulation scenarios except the scenario of a 2 °C temperature increase. These results indicate that temperature increases can influence the CSP in Yunnan Province, and the largest impact emerged in the 2 °C increase scenario.

Leaf Area Index (LAI Estimation of Boreal Forest Using Wide Optics Airborne Winter Photos

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Pauline Stenberg

2009-12-01

Full Text Available A new simple airborne method based on wide optics camera is developed for leaf area index (LAI estimation in coniferous forests. The measurements are carried out in winter, when the forest floor is completely snow covered and thus acts as a light background for the hemispherical analysis of the images. The photos are taken automatically and stored on a laptop during the flights. The R2 value of the linear regression of the airborne and ground based LAI measurements was 0.89.

Boreal coniferous forest density leads to significant variations in soil physical and geochemical properties

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Bastianelli, Carole; Ali, Adam A.; Beguin, Julien; Bergeron, Yves; Grondin, Pierre; Hély, Christelle; Paré, David

2017-07-01

At the northernmost extent of the managed forest in Quebec, Canada, the boreal forest is currently undergoing an ecological transition between two forest ecosystems. Open lichen woodlands (LW) are spreading southward at the expense of more productive closed-canopy black spruce-moss forests (MF). The objective of this study was to investigate whether soil properties could distinguish MF from LW in the transition zone where both ecosystem types coexist. This study brings out clear evidence that differences in vegetation cover can lead to significant variations in soil physical and geochemical properties.Here, we showed that soil carbon, exchangeable cations, and iron and aluminium crystallinity vary between boreal closed-canopy forests and open lichen woodlands, likely attributed to variations in soil microclimatic conditions. All the soils studied were typical podzolic soil profiles evolved from glacial till deposits that shared a similar texture of the C layer. However, soil humus and the B layer varied in thickness and chemistry between the two forest ecosystems at the pedon scale. Multivariate analyses of variance were used to evaluate how soil properties could help distinguish the two types at the site scale. MF humus (FH horizons horizons composing the O layer) showed significantly higher concentrations of organic carbon and nitrogen and of the main exchangeable base cations (Ca, Mg) than LW soils. The B horizon of LW sites held higher concentrations of total Al and Fe oxides and particularly greater concentrations of inorganic amorphous Fe oxides than MF mineral soils, while showing a thinner B layer. Overall, our results show that MF store three times more organic carbon in their soils (B+FH horizons, roots apart) than LW. We suggest that variations in soil properties between MF and LW are linked to a cascade of events involving the impacts of natural disturbances such as wildfires on forest regeneration that determines the vegetation structure (stand density

Boreal coniferous forest density leads to significant variations in soil physical and geochemical properties

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C. Bastianelli

2017-07-01

Full Text Available At the northernmost extent of the managed forest in Quebec, Canada, the boreal forest is currently undergoing an ecological transition between two forest ecosystems. Open lichen woodlands (LW are spreading southward at the expense of more productive closed-canopy black spruce–moss forests (MF. The objective of this study was to investigate whether soil properties could distinguish MF from LW in the transition zone where both ecosystem types coexist. This study brings out clear evidence that differences in vegetation cover can lead to significant variations in soil physical and geochemical properties.Here, we showed that soil carbon, exchangeable cations, and iron and aluminium crystallinity vary between boreal closed-canopy forests and open lichen woodlands, likely attributed to variations in soil microclimatic conditions. All the soils studied were typical podzolic soil profiles evolved from glacial till deposits that shared a similar texture of the C layer. However, soil humus and the B layer varied in thickness and chemistry between the two forest ecosystems at the pedon scale. Multivariate analyses of variance were used to evaluate how soil properties could help distinguish the two types at the site scale. MF humus (FH horizons horizons composing the O layer showed significantly higher concentrations of organic carbon and nitrogen and of the main exchangeable base cations (Ca, Mg than LW soils. The B horizon of LW sites held higher concentrations of total Al and Fe oxides and particularly greater concentrations of inorganic amorphous Fe oxides than MF mineral soils, while showing a thinner B layer. Overall, our results show that MF store three times more organic carbon in their soils (B+FH horizons, roots apart than LW. We suggest that variations in soil properties between MF and LW are linked to a cascade of events involving the impacts of natural disturbances such as wildfires on forest regeneration that determines the vegetation

Underestimated effects of low temperature during early growing season on carbon sequestration of a subtropical coniferous plantation

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W.-J. Zhang

2011-06-01

Full Text Available The impact of air temperature in early growing season on the carbon sequestration of a subtropical coniferous plantation was discussed through analyzing the eddy flux observations at Qianyanzhou (QYZ site in southern China from 2003 to 2008. This site experienced two cold early growing seasons (with temperature anomalies of 2–5 °C in 2005 and 2008, and a severe summer drought in 2003.
Results indicated that the low air temperature from January to March was the major factor controlling the inter-annual variations in net carbon uptake at this site, rather than the previously thought summer drought. The accumulative air temperature from January to February showed high correlation (R²=0.970, p<0.001 with the annual net ecosystem production (NEP. This was due to the controls of early-month temperature on the plant phenology developing and the growing season length at this subtropical site. The cold spring greatly shortened the growing season length and therefore reduced the carbon uptake period. The eddy flux observations showed a carbon loss of 4.04 g C m⁻² per growing-season day at this coniferous forest site. On the other hand, the summer drought also reduced the net carbon uptake strength because the photosynthesis was more sensitive to water deficit stress than the ecosystem respiration. However, the impact of summer drought occurred within a relatively shorter period and the carbon sequestration went back to the normal level once the drought was relieved.

Fatty acid profiles of great tit ( Parus major) eggs differ between urban and rural habitats, but not between coniferous and deciduous forests

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Toledo, Alejandra; Andersson, Martin N.; Wang, Hong-Lei; Salmón, Pablo; Watson, Hannah; Burdge, Graham C.; Isaksson, Caroline

2016-08-01

Early-life nutrition is an important determinant of both short- and long-term performance and fitness. The avian embryo develops within an enclosed package of nutrients, of which fatty acids (FA) are essential for many aspects of development. The FA composition of yolk depends on maternal nutrition and condition prior to egg formation, which may be affected by the external environment. To test if maternal environment affects yolk FA composition, we investigated whether the FA composition of great tit ( Parus major) egg yolks differed between urban and rural habitats, and between deciduous and coniferous habitats. The results reveal differences in FA composition between eggs laid in urban and rural habitats, but not between eggs from the coniferous and deciduous habitats. To a large extent, this difference likely reflects dietary differences associated with urban habitats rather than dominating vegetation type. Specifically, urban yolks contained lower proportions of both ω-3 and ω-6 polyunsaturated FAs (PUFA), which are important for chick development. We also found a positive association between the proportion of saturated fatty acids and laying date, and a negative association between the proportion of ω-6 PUFA and clutch size. Given that urbanization is expanding rapidly, future studies should investigate whether factors such as anthropogenic food in the urban environment underlie these differences and whether they impair chick development.

Fern extracts potentiate fluconazole activity and inhibit morphological changes in Candida species

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Maria A. Freitas

2017-11-01

Conclusions: The extracts obtained from the fern species L. venustum and P. calomelanos dose not present significant antifungal activity. However, P. calomelanos potentiates the activity of fluconazole and both extracts inhibits the morphological changes in Candida species, indicating that they have potential pharmacological activity as modulators of fungal biology. Therefore, novel studies are required to characterize the interference of these extracts in the virulence and pathogenicity of Candida species as well as the potential of fern species to treat fungal infections.

Ecological factors governing the distribution of soil microfungi in some forest soils of Pachmarhi Hills, India

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Shashi Chauhan

2014-01-01

Full Text Available An ecological study of the microfungi occurring in the various forest soils of Pachmarhi Hills, India has been carried-out by the soil plate technique. Soil samples from 5 different forest communities viz., moist deciduous forest dominated by tree ferns, Diospyros forest, Terminalia forest, Shorea forest and scrub forest dominated by Acacia and Dalbergia sp. were collected during October, 1983. Some physico-chemical characteristics of the soil were analysed and their role in distribution of fungi in 5 soil types was studied and discussed. 43 fungal species were isolated, of which Asperigillus niger I and Penicillium janthinellum occurred in all the 5 soil types. Statistically, none of the edaphic factors showed positive significant correlation with the number of fungi.

Phototropic leaf movements and photosynthetic performance in an amphibious fern, Marsilea quadrifolia.

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Kao, Wen-Yuan; Lin, Bai-Ling

2010-09-01

Diurnal phototropism has not been reported in ferns. In this study we found that the four leaflets of the amphibious fern Marsilea quadrifolia are capable of adjusting their leaflet angle and leaflet azimuth in response to changes in the position of the sun's direct beam, exhibiting more diaphototropic movements (orienting the plane of the lamina perpendicular to incident light) in the morning and late afternoon, and more paraphototropic movements (orienting the plane of the lamina parallel to incident light) at noon. In addition, by cutting off the leaflet lamina and covering portions of leaflets with black tape, the junction between the leaflet and petiole was found to be responsible for light reception. Among the light spectrum investigated, blue light was the most effective at inducing diaphototropism. The role of diurnal phototropism in enhancing carbon return and ameliorating photoinhibition was also evaluated. It was concluded that diurnal phototropic leaf movement represents one of the plastic responses enabling this amphibious fern to grow under terrestrial conditions.

Jasmonic and salicylic acid response in the fern Azolla filiculoides and its cyanobiont.

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de Vries, Sophie; de Vries, Jan; Teschke, Hendrik; von Dahlen, Janina K; Rose, Laura E; Gould, Sven B

2018-01-03

Plants sense and respond to microbes utilizing a multilayered signalling cascade. In seed plants, the phytohormones jasmonic and salicylic acid (JA and SA) are key denominators of how plants respond to certain microbes. Their interplay is especially well-known for tipping the scales in plants' strategies of dealing with phytopathogens. In non-angiosperm lineages, the interplay is less well understood, but current data indicate that it is intertwined to a lesser extent and the canonical JA/SA antagonism appears to be absent. Here, we used the water fern Azolla filiculoides to gain insights into the fern's JA/SA signalling and the molecular communication with its unique nitrogen fixing cyanobiont Nostoc azollae, which the fern inherits both during sexual and vegetative reproduction. By mining large-scale sequencing data, we demonstrate that Azolla has most of the genetic repertoire to produce and sense JA and SA. Using qRT-PCR on the identified biosynthesis and signalling marker genes, we show that Azolla is responsive to exogenously applied SA. Furthermore, exogenous SA application influenced the abundance and gene expression of Azolla's cyanobiont. Our data provide a framework for JA/SA signalling in ferns and suggest that SA might be involved in Azolla's communication with its vertically inherited cyanobiont. © 2018 John Wiley & Sons Ltd.

Harvesting interacts with climate change to affect future habitat quality of a focal species in eastern Canada's boreal forest.

Science.gov (United States)

Tremblay, Junior A; Boulanger, Yan; Cyr, Dominic; Taylor, Anthony R; Price, David T; St-Laurent, Martin-Hugues

2018-01-01

Many studies project future bird ranges by relying on correlative species distribution models. Such models do not usually represent important processes explicitly related to climate change and harvesting, which limits their potential for predicting and understanding the future of boreal bird assemblages at the landscape scale. In this study, we attempted to assess the cumulative and specific impacts of both harvesting and climate-induced changes on wildfires and stand-level processes (e.g., reproduction, growth) in the boreal forest of eastern Canada. The projected changes in these landscape- and stand-scale processes (referred to as "drivers of change") were then assessed for their impacts on future habitats and potential productivity of black-backed woodpecker (BBWO; Picoides arcticus), a focal species representative of deadwood and old-growth biodiversity in eastern Canada. Forest attributes were simulated using a forest landscape model, LANDIS-II, and were used to infer future landscape suitability to BBWO under three anthropogenic climate forcing scenarios (RCP 2.6, RCP 4.5 and RCP 8.5), compared to the historical baseline. We found climate change is likely to be detrimental for BBWO, with up to 92% decline in potential productivity under the worst-case climate forcing scenario (RCP 8.5). However, large declines were also projected under baseline climate, underlining the importance of harvest in determining future BBWO productivity. Present-day harvesting practices were the single most important cause of declining areas of old-growth coniferous forest, and hence appeared as the single most important driver of future BBWO productivity, regardless of the climate scenario. Climate-induced increases in fire activity would further promote young, deciduous stands at the expense of old-growth coniferous stands. This suggests that the biodiversity associated with deadwood and old-growth boreal forests may be greatly altered by the cumulative impacts of natural and

Harvesting interacts with climate change to affect future habitat quality of a focal species in eastern Canada's boreal forest.

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Junior A Tremblay

Full Text Available Many studies project future bird ranges by relying on correlative species distribution models. Such models do not usually represent important processes explicitly related to climate change and harvesting, which limits their potential for predicting and understanding the future of boreal bird assemblages at the landscape scale. In this study, we attempted to assess the cumulative and specific impacts of both harvesting and climate-induced changes on wildfires and stand-level processes (e.g., reproduction, growth in the boreal forest of eastern Canada. The projected changes in these landscape- and stand-scale processes (referred to as "drivers of change" were then assessed for their impacts on future habitats and potential productivity of black-backed woodpecker (BBWO; Picoides arcticus, a focal species representative of deadwood and old-growth biodiversity in eastern Canada. Forest attributes were simulated using a forest landscape model, LANDIS-II, and were used to infer future landscape suitability to BBWO under three anthropogenic climate forcing scenarios (RCP 2.6, RCP 4.5 and RCP 8.5, compared to the historical baseline. We found climate change is likely to be detrimental for BBWO, with up to 92% decline in potential productivity under the worst-case climate forcing scenario (RCP 8.5. However, large declines were also projected under baseline climate, underlining the importance of harvest in determining future BBWO productivity. Present-day harvesting practices were the single most important cause of declining areas of old-growth coniferous forest, and hence appeared as the single most important driver of future BBWO productivity, regardless of the climate scenario. Climate-induced increases in fire activity would further promote young, deciduous stands at the expense of old-growth coniferous stands. This suggests that the biodiversity associated with deadwood and old-growth boreal forests may be greatly altered by the cumulative impacts of

Specifics of fire-preventing arrangements in the forests of Baikal region

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M. D. Evdokimenko

2017-10-01

Full Text Available Fire risk in major forest types and concomitant vegetation complexes across all altitudinal belts has been analyzed. High fire risk in woodlands is determined by domination of light needle coniferous stands in their structure and specific climate with continuous spring-summer droughts. Thus, the risk of landscape wildfires is high. The most drastic situations occur in very dry years of climatic cycles during forest pyrogenic anomalies when fire spreads across the main landscapes in several nature areas. Current fire-frequency is incompatible with high biosphere status of nature complex of Lake Baikal as an object of the World nature heritage. Extensive forest exploitation is unacceptable as well. Fire-prevention measures in the area require modernization. According to the results of many years of comparative studies of fire risk in phytocenoses with different species composition and structure of tree layers, the techniques of making fire stopping barriers were developed. The scheme of dividing the managed forests into isolated cells separated by special obstacles and fire-resistant forest borders combined with commonly used fire barriers is suggested. Fire-resistant barriers should be formed on both sides of main roads, passing through the intensively exploited woodlands dominating with common pine Pinus sylvestris L., Siberian stone pine Pinus sibirica Du Tour, Siberian spruce Picea obovata Ledeb., and Siberian fir Abies sibirica Ledeb. tree species. Such barriers are intended to stop the fire front of crown fires. The barrier width is determined by the cell order. The barriers are bordered with clearings with scarified soil strips of 3–4 meters in width. Trees and shrubs damaged in the process are removed during clutter cleaning. In places where the barrier passes through coniferous tree stands longitudinal corridors with scarified soil strips every 20–30 meters should be made. Reforestation and thinning are supposed to be combined with

Nitrogen retention in contrasting temperate forests exposed to high nitrogen deposition

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Staelens, J.; Adriaenssens, S.; Wuyts, K.; Verheyen, K.; Boeckx, P. F.

2011-12-01

A better understanding of factors affecting nitrogen (N) retention is needed to assess the impact of changing anthropogenic N emissions and climatic conditions on N cycling and N loss by terrestrial ecosystems. Retention of N has been demonstrated for a wide range of forests, including ecosystems exposed to chronically enhanced N deposition, but it is still unclear which factors determine this N retention capacity. Therefore, we examined the possible effects of forest type on N retention using stable N isotopes. The study was carried out in adjacent equal-aged deciduous (pedunculate oak (Quercus robur L.)) and coniferous (Scots pine (Pinus sylvestris L.)) stands with a similar stand history and growing on a well-drained sandy soil in a region with enhanced N deposition (Belgium). The N input-output budgets and gross soil N transformation rates differed significantly between the two stands. The forest floor was exposed to a high inorganic N input from atmospheric deposition, which was nearly twice as high in the pine stand (33 ± 2 kg N ha-1 yr-1; mean ± standard error) as in the oak stand (18 ± 1 kg N ha-1 yr-1). The N input was reflected in the soil solution under the rooting zone, but the mean nitrate concentration was eight times higher under pine (19 ± 5 mg N L-1) than under oak (2.3 ± 0.9 mg N L-1). Gross N dynamics in the mineral topsoil were determined by in situ 15N labelling of undisturbed soil cores combined with numerical data analysis. Gross N mineralization was two times faster in the oak soil while nitrate production was two times faster in the pine soil, indicating a dominant effect of vegetation cover on soil N cycling. The higher gross nitrification, particularly due to oxidation of organic N, in the pine soil compared to the oak soil, combined with negligible nitrate immobilization, was in line with the higher nitrate leaching under the pine forest. On a larger spatial and temporal scale, the fate of dissolved inorganic N within these forests

The present is not the key to the past: A polar forest from the Permian of Antarctica

International Nuclear Information System (INIS)

Taylor, E.L.; Taylor, T.N.; Cuneo, N.R.

1992-01-01

An in situ Upper Permian fossil forest in the central Transantarctic Mountains near the Beardmore Glacier includes 15 permineralized trunks in growth position; the paleolatitude of the site was approximately 80 degree to 85 degree south. Numerous leaves of the seed fern Glossopteris are present in the shale in which the trunks are rooted. The trunks are permineralized and tree rings reveal that the forest was a rapidly growing and young forest, persisting in an equable, strongly seasonal climate - a scenario that does not fit with some climate reconstructions for this time period

Growth responses of trees and understory plants to nitrogen fertilization in a subtropical forest in China

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Tian, Di; Li, Peng; Fang, Wenjing; Xu, Jun; Luo, Yongkai; Yan, Zhengbing; Zhu, Biao; Wang, Jingjing; Xu, Xiaoniu; Fang, Jingyun

2017-07-01

Reactive nitrogen (N) increase in the biosphere has been a noteworthy aspect of global change, producing considerable ecological effects on the functioning and dynamics of the terrestrial ecosystems. A number of observational studies have explored responses of plants to experimentally simulated N enrichment in boreal and temperate forests. Here we investigate how the dominant trees and different understory plants respond to experimental N enrichment in a subtropical forest in China. We conducted a 3.4-year N fertilization experiment in an old-aged subtropical evergreen broad-leaved forest in eastern China with three treatment levels applied to nine 20 m × 20 m plots and replicated in three blocks. We divided the plants into trees, saplings, shrubs (including tree seedlings), and ground-cover plants (ferns) according to the growth forms, and then measured the absolute and relative basal area increments of trees and saplings and the aboveground biomass of understory shrubs and ferns. We further grouped individuals of the dominant tree species, Castanopsis eyrei, into three size classes to investigate their respective growth responses to the N fertilization. Our results showed that the plot-averaged absolute and relative growth rates of basal area and aboveground biomass of trees were not affected by N fertilization. Across the individuals of C. eyrei, the small trees with a DBH (diameter at breast height) of 5-10 cm declined by 66.4 and 59.5 %, respectively, in N50 (50 kg N ha-1 yr-1) and N100 fertilized plots (100 kg N ha-1 yr-1), while the growth of median and large trees with a DBH of > 10 cm did not significantly change with the N fertilization. The growth rate of small trees, saplings, and the aboveground biomass of understory shrubs and ground-cover ferns decreased significantly in the N-fertilized plots. Our findings suggested that N might not be a limiting nutrient in this mature subtropical forest, and that the limitation of other nutrients in the forest

Growth responses of trees and understory plants to nitrogen fertilization in a subtropical forest in China

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D. Tian

2017-07-01

Full Text Available Reactive nitrogen (N increase in the biosphere has been a noteworthy aspect of global change, producing considerable ecological effects on the functioning and dynamics of the terrestrial ecosystems. A number of observational studies have explored responses of plants to experimentally simulated N enrichment in boreal and temperate forests. Here we investigate how the dominant trees and different understory plants respond to experimental N enrichment in a subtropical forest in China. We conducted a 3.4-year N fertilization experiment in an old-aged subtropical evergreen broad-leaved forest in eastern China with three treatment levels applied to nine 20 m  ×  20 m plots and replicated in three blocks. We divided the plants into trees, saplings, shrubs (including tree seedlings, and ground-cover plants (ferns according to the growth forms, and then measured the absolute and relative basal area increments of trees and saplings and the aboveground biomass of understory shrubs and ferns. We further grouped individuals of the dominant tree species, Castanopsis eyrei, into three size classes to investigate their respective growth responses to the N fertilization. Our results showed that the plot-averaged absolute and relative growth rates of basal area and aboveground biomass of trees were not affected by N fertilization. Across the individuals of C. eyrei, the small trees with a DBH (diameter at breast height of 5–10 cm declined by 66.4 and 59.5 %, respectively, in N50 (50 kg N ha−1 yr−1 and N100 fertilized plots (100 kg N ha−1 yr−1, while the growth of median and large trees with a DBH of  >  10 cm did not significantly change with the N fertilization. The growth rate of small trees, saplings, and the aboveground biomass of understory shrubs and ground-cover ferns decreased significantly in the N-fertilized plots. Our findings suggested that N might not be a limiting nutrient in this mature subtropical

Precipitation and air temperature control the variations of dissolved organic matter along an altitudinal forest gradient, Gongga Mountains, China.

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Hu, Zhaoyong; Wang, Genxu; Sun, Xiangyang

2017-04-01

Dissolved organic carbon (DOC) and dissolved organic nitrogen (DON) contribute significantly to C and N cycling in forest ecosystems. Little information is available on the variations in the DOC and DON concentrations and depositions in bulk and stand precipitation within forests along an altitudinal gradient. To determine the temporal variations in the DOC and DON concentrations and depositions in different forests and the spatial variations along the elevation gradient, the DOC and DON concentrations and depositions were measured in bulk precipitation, throughfall, and stemflow within three forest types, i.e., broadleaf forest (BLF), broadleaf-coniferous forest (BCF), and coniferous forest (CF), during the wet season (May to October) on Gongga Mountain, China, in 2015. The concentrations of bulk precipitation in BLF, BCF, and CF were 3.92, 4.04, and 2.65 mg L -1 , respectively, for DOC and were 0.38, 0.26, and 0.29 mg L -1 , respectively, for DON. BCF had the highest DOC deposition both in bulk precipitation (45.12 kg ha -1 ) and stand precipitation (98.52 kg ha -1 ), whereas the highest DON deposition was in BLF (3.62 kg ha -1 bulk precipitation and 4.11 kg ha -1 stand precipitation) during the study period. The meteorological conditions of precipitation and air temperature significantly influenced the dissolved organic matter (DOM) depositions along the elevation gradient. The leaf area index did not show any correlation with DOM depositions during the growing season.

Pyrogenic Transformations of the Baikal Lake Forests. Retrospective and Contemporary Issues

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M. D. Yevdokimenko

2014-06-01

Full Text Available In the forests of the Baikal Lake basin annual fire activity historically has been higher as compared to surrounding forest areas due to specific climatic conditions and altitude-controlled vegetation structure. The regional forests, predominantly light coniferous, develop under a high or, in dry years, extreme-fire-activity regime. Common pine and larch tree stands of fire origin are periodically thinned by fire. The productivity of the fire-intact parts of such stands decreases as a result of fire-caused soil condition disturbances. In extreme fire years, large fires cover landscapes and lead to irreversible forest ecosystem degradation and, hence, to local deforestation. In the past, forest fire activity and area burned increased with increasing use of the regional forests beginning with hunting, wood extraction by dwellers of local settlements, Trans-Siberian Rail Road building and, finally, industrial-scale logging. In 1970–1980, the regional fire situation was successfully controlled due to improvements of forest use and protection. However, the recently relaxed forest economy standards have resulted in loss of the progress achieved.

THE DIVERSITY OF EPIPHYTIC FERN ON THE OIL PALM TREE (Elaeis guineensis Jacq. IN PEKANBARU, RIAU

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Nery Sofiyanti

2015-02-01

Full Text Available Oil palm (Elaeis guineensis is one  main commodity in Riau Province. Morphologically, the trunk of oil palm  has suitable environment for the growth of epiphytic fern, due to its broaden base of petiole that may accumulate organic and anorganic debrish. The objective of this study was to investigate the diversity of epiphytic fern on the oil palm tree. A total of 125 oil palm trees from seven  study sites in Pekanbaru, Riau were observed. The number of epiphytic ferns identified in this study was 16 species belongs to six families.

Harvesting interacts with climate change to affect future habitat quality of a focal species in eastern Canada’s boreal forest

Science.gov (United States)

Boulanger, Yan; Cyr, Dominic; Taylor, Anthony R.; Price, David T.; St-Laurent, Martin-Hugues

2018-01-01

Many studies project future bird ranges by relying on correlative species distribution models. Such models do not usually represent important processes explicitly related to climate change and harvesting, which limits their potential for predicting and understanding the future of boreal bird assemblages at the landscape scale. In this study, we attempted to assess the cumulative and specific impacts of both harvesting and climate-induced changes on wildfires and stand-level processes (e.g., reproduction, growth) in the boreal forest of eastern Canada. The projected changes in these landscape- and stand-scale processes (referred to as “drivers of change”) were then assessed for their impacts on future habitats and potential productivity of black-backed woodpecker (BBWO; Picoides arcticus), a focal species representative of deadwood and old-growth biodiversity in eastern Canada. Forest attributes were simulated using a forest landscape model, LANDIS-II, and were used to infer future landscape suitability to BBWO under three anthropogenic climate forcing scenarios (RCP 2.6, RCP 4.5 and RCP 8.5), compared to the historical baseline. We found climate change is likely to be detrimental for BBWO, with up to 92% decline in potential productivity under the worst-case climate forcing scenario (RCP 8.5). However, large declines were also projected under baseline climate, underlining the importance of harvest in determining future BBWO productivity. Present-day harvesting practices were the single most important cause of declining areas of old-growth coniferous forest, and hence appeared as the single most important driver of future BBWO productivity, regardless of the climate scenario. Climate-induced increases in fire activity would further promote young, deciduous stands at the expense of old-growth coniferous stands. This suggests that the biodiversity associated with deadwood and old-growth boreal forests may be greatly altered by the cumulative impacts of natural and

Effects of fire severity on plant nutrient uptake reinforce alternate pathways of succession in boreal forests

Science.gov (United States)

A. Shenoy; K. Kielland; J.F. Johnstone

2013-01-01

Fire activity in the North American boreal region is projected to increase under a warming climate and trigger changes in vegetation composition. In black spruce forests of interior Alaska, fire severity impacts residual organic layer depth which is strongly linked to the relative dominance of deciduous versus coniferous trees in early succession. These alternate...

Atmospheric mercury deposition to forests in the eastern USA

International Nuclear Information System (INIS)

Risch, Martin R.; DeWild, John F.; Gay, David A.; Zhang, Leiming; Boyer, Elizabeth W.; Krabbenhoft, David P.

2017-01-01

Atmospheric mercury (Hg) deposition to forests is important because half of the land cover in the eastern USA is forest. Mercury was measured in autumn litterfall and weekly precipitation samples at a total of 27 National Atmospheric Deposition Program (NADP) monitoring sites in deciduous and mixed deciduous-coniferous forests in 16 states in the eastern USA during 2007–2014. These simultaneous, uniform, repeated, annual measurements of forest Hg include the broadest area and longest time frame to date. The autumn litterfall-Hg concentrations and litterfall mass at the study sites each year were combined with annual precipitation-Hg data. Rates of litterfall-Hg deposition were higher than or equal to precipitation-Hg deposition rates in 70% of the annual data, which indicates a substantial contribution from litterfall to total atmospheric-Hg deposition. Annual litterfall-Hg deposition in this study had a median of 11.7 μg per square meter per year (μg/m 2 /yr) and ranged from 2.2 to 23.4 μg/m 2 /yr. It closely matched modeled dry-Hg deposition, based on land cover at selected NADP Hg-monitoring sites. Mean annual atmospheric-Hg deposition at forest study sites exhibited a spatial pattern partly explained by statistical differences among five forest-cover types and related to the mapped density of Hg emissions. Forest canopies apparently recorded changes in atmospheric-Hg concentrations over time because litterfall-Hg concentrations decreased year to year and litterfall-Hg concentrations were significantly higher in 2007–2009 than in 2012–2014. These findings reinforce reported decreases in Hg emissions and atmospheric elemental-Hg concentrations during this same time period. Methylmercury (MeHg) was detected in all litterfall samples at all sites, compared with MeHg detections in less than half the precipitation samples at selected sites during the study. These results indicate MeHg in litterfall is a pathway into the terrestrial food web where it can

PIXE study on arsenic accumulation by a fern. Pteris vittata

International Nuclear Information System (INIS)

Yamazaki, H.; Ishii, K.; Matsuyama, S.

2010-01-01

Pteris vittata is a fern reported to be an arsenic hyper-accumulator. To develop the practical application of the fern to a phytoremediation technique, it is necessary to explicate the effective accumulation mechanism. In this study, the arsenic distribution and the elemental correlation in the cellular level were examined in the fronds supplied with arsenate and arsenite separately via xylem vessel using an in-air micro-PIXE system at Tohoku University. The difference in transportation rate between arsenate and arsenite as well as the translocation of elements necessary for plant metabolism was revealed in different tissues of the fronds accumulating arsenic in high concentration. Hence, the in-air micro-PIXE analysis is an effective measure for undertaking phytoremediation research of hyper-accumulator plants. (author)

Study on the forest vegetation restoration monitoring using HJ-1A hyperspectral data

International Nuclear Information System (INIS)

Chuan, Zhang; Fawang, Ye; Hongcheng, Liu; Haixia, He

2014-01-01

In this paper, Xunke County was studied using HJ-1A hyperspectral data for monitoring vegetation restoration after forest fires. The pre-processing procedure including data format conversion, image mosaicing and atmospheric correction. Support vector machine classification was used to perform surface feature identification based on the extracted spectral end-members. On that basis, the image area was divided into seven categories and statistical analysis of classification types was performed. The results showed that HJ-1A hyperspectral data had great potential in fine classification of surface features and the accuracy of classification was 91.8%. The mild and severe fire-affected area extraction provided useful reference for disaster recovery monitoring. Furthermore, the distinction between coniferous forest and broadleaved forest can offer useful information for forest fire prevention and early warning to some extent

New observations and synthesis of paleogene heterosporous water ferns

NARCIS (Netherlands)

Collinson, M.E.; Smith, S.Y.; van Konijnenburg-van Cittert, J.H.A.; Batten, D.J.; Refidaff, C.; Barke, J.; Marone, F.

Premise of research. Reproductive structures of modern genera of heterosporous water ferns (Marsileaceae and Salviniaceae) are widespread and abundant in plant mesofossil assemblages from the Paleogene. For Salviniaceae, whole fertile fossil plants give a good understanding of morphology. These

Habitat Requirements of Breeding Black-Backed Woodpeckers (Picoides arcticus in Managed, Unburned Boreal Forest

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Junior A. Tremblay

2009-06-01

Full Text Available We investigated home-range characteristics and habitat selection by Black-backed Woodpeckers (Picoides arcticus in an unburned, boreal forest landscape managed by mosaic harvesting in Quebec, Canada. Habitat selection by this species was specifically examined to determine home-range establishment and foraging activities. We hypothesized that Black-backed Woodpeckers would respond to harvesting by adjusting their home-range size as a function of the amount of dead wood available. Twenty-two birds were tracked using radiotelemetry, and reliable estimates of home-range size were obtained for seven breeding individuals (six males and one female. The average home-range size was 151.5 ± 18.8 ha (range: 100.4-256.4 ha. Our results indicate that this species establishes home ranges in areas where both open and forested habitats are available. However, during foraging activities, individuals preferentially selected areas dominated by old coniferous stands. The study also showed that the spatial distribution of preferred foraging habitat patches influenced space use, with home-range area increasing with the median distance between old coniferous habitat patches available within the landscape. Finally, these data show that Black-backed Woodpeckers may successfully breed in an unburned forest with at least 35 m3 • ha-1 of dead wood, of which 42% (15 m3 • ha-1 is represented by dead wood at the early decay stage.

Ferns are less dependent on passive dilution by cell expansion to coordinate leaf vein and stomatal spacing than angiosperms.

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Madeline R Carins Murphy

Full Text Available Producing leaves with closely spaced veins is a key innovation linked to high rates of photosynthesis in angiosperms. A close geometric link between veins and stomata in angiosperms ensures that investment in enhanced venous water transport provides the strongest net carbon return to the plant. This link is underpinned by "passive dilution" via expansion of surrounding cells. However, it is not known whether this 'passive dilution' mechanism is present in plant lineages other than angiosperms and is another key feature of the angiosperms' evolutionary success. Consequently, we sought to determine whether the 'passive dilution' mechanism is; (i exclusive to the angiosperms, (ii a conserved mechanism that evolved in the common ancestor of ferns and angiosperms, or (iii has evolved continuously over time. To do this we first we assessed the plasticity of vein and stomatal density and epidermal cell size in ferns in response to light environment. We then compared the relationships between these traits found among ferns with modelled relationships that assume vein and stomatal density respond passively to epidermal cell expansion, and with those previously observed in angiosperms. Vein density, stomatal density and epidermal cell size were linked in ferns with remarkably similar relationships to those observed in angiosperms, except that fern leaves had fewer veins per stomata. However, plasticity was limited in ferns and stomatal spacing was dependent on active stomatal differentiation as well as passive cell expansion. Thus, ferns (like angiosperms appear to coordinate vein and stomatal density with epidermal cell expansion to some extent to maintain a constant ratio between veins and stomata in the leaf. The different general relationships between vein density and stomatal density in ferns and angiosperms suggests the groups have different optimum balances between the production of vein tissue dedicated to water supply and stomatal tissue for gas

Monitoring Forest Recovery Following Wildfire and Harvest in Boreal Forests Using Satellite Imagery

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Amar Madoui

2015-11-01

Full Text Available In the managed boreal forest, harvesting has become a disturbance as important as fire. To assess whether forest recovery following both types of disturbance is similar, we compared post-disturbance revegetation rates of forests in 22 fire events and 14 harvested agglomerations (harvested areas over 5–10 years in the same vicinity in the western boreal forest of Quebec. Pre-disturbance conditions were first compared in terms of vegetation cover types and surficial deposit types using an ordination technique. Post-disturbance changes over 30 years in land cover types were characterized by vectors of succession in an ordination. Four post-disturbance stages were identified from the 48 land thematic classes in the Landsat images: “S0” stand initiation phase; “S1” early regeneration phase; “S2” stem exclusion phase; and “S3” the coniferous forest. Analyses suggest that fire occurs in both productive and unproductive forests, which is not the case for harvesting. Revegetation rates (i.e., rapidity with which forest cover is re-established appeared to be more advanced in harvested agglomerations when compared with entire fire events. However, when considering only the productive forest fraction of each fire, the revegetation rates are comparable between the fire events and the harvested agglomerations. The S0 is practically absent from harvested agglomerations, which is not the case in the fire events. The difference in revegetation rates between the two disturbance types could therefore be attributed mostly to the fact that fire also occurs in unproductive forest, a factor that has to be taken into account in such comparisons.

Preface and introduction to 'The Response of Western Forests to Air Pollution'. Book chapter

International Nuclear Information System (INIS)

Olson, R.; Boehm, M.; Brinkley, D.

1992-01-01

The book addresses the relationships between air pollution in the western United States and trends in the growth and condition of western coniferous forests. The West is defined in this case as the eleven conterminous states of California, Oregon, Washington, Idaho, Nevada, Arizona, New Mexico, Utah, Colorado, Wyoming, and Montana. The major atmospheric pollutants to which forests in this region are exposed are sulfur and nitrogen compounds and ozone. Ozone is a secondary pollutant formed by photolytic reactions involving nitrogen oxides and hydrocarbons. The potential effects of atmospheric pollution on these forests include foliar injury, alteration of growth rates and patterns, soil acidification, shifts in species composition, and modification of the effects of natural stressors

Towards operational remote sensing of forest carbon balance across Northern Europe

Directory of Open Access Journals (Sweden)

P. Olofsson

2008-05-01

Full Text Available Monthly averages of ecosystem respiration (ER, gross primary production (GPP and net ecosystem exchange (NEE over Scandinavian forest sites were estimated using regression models driven by air temperature (AT, absorbed photosynthetically active radiation (APAR and vegetation indices. The models were constructed and evaluated using satellite data from Terra/MODIS and measured data collected at seven flux tower sites in northern Europe. Data used for model construction was excluded from the evaluation. Relationships between ground measured variables and the independent variables were investigated.

It was found that the enhanced vegetation index (EVI at 250 m resolution was highly noisy for the coniferous sites, and hence, 1 km EVI was used for the analysis. Linear relationships between EVI and the biophysical variables were found: correlation coefficients between EVI and GPP, NEE, and AT ranged from 0.90 to 0.79 for the deciduous data, and from 0.85 to 0.67 for the coniferous data. Due to saturation, there were no linear relationships between normalized difference vegetation index (NDVI and the ground measured parameters found at any site. APAR correlated better with the parameters in question than the vegetation indices. Modeled GPP and ER were in good agreement with measured values, with more than 90% of the variation in measured GPP and ER being explained by the coniferous models. The site-specific respiration rate at 10°C (R₁₀ was needed for describing the ER variation between sites. Even though monthly NEE was modeled with less accuracy than GPP, 61% and 75% (dec. and con., respectively of the variation in the measured time series was explained by the model. These results are important for moving towards operational remote sensing of forest carbon balance across Northern Europe.

Application of GIS to Empirical Windthrow Risk Model in Mountain Forested Landscapes

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Lukas Krejci

2018-02-01

Full Text Available Norway spruce dominates mountain forests in Europe. Natural variations in the mountainous coniferous forests are strongly influenced by all the main components of forest and landscape dynamics: species diversity, the structure of forest stands, nutrient cycling, carbon storage, and other ecosystem services. This paper deals with an empirical windthrow risk model based on the integration of logistic regression into GIS to assess forest vulnerability to wind-disturbance in the mountain spruce forests of Šumava National Park (Czech Republic. It is an area where forest management has been the focus of international discussions by conservationists, forest managers, and stakeholders. The authors developed the empirical windthrow risk model, which involves designing an optimized data structure containing dependent and independent variables entering logistic regression. The results from the model, visualized in the form of map outputs, outline the probability of risk to forest stands from wind in the examined territory of the national park. Such an application of the empirical windthrow risk model could be used as a decision support tool for the mountain spruce forests in a study area. Future development of these models could be useful for other protected European mountain forests dominated by Norway spruce.

Energy balance of a sparse coniferous high-latitude forest under winter conditions

NARCIS (Netherlands)

Gryning, S.E.; Batchvarova, E.; DeBruin, H.A.R.

2001-01-01

Measurements carried out in Northern Finland on radiation and turbulent fluxes over a sparse, sub-arctic boreal forest with snow covered ground were analysed. The measurements represent late winter conditions characterised by low solar elevation angles. During the experiment (12-24 March 1997) day

Nona Fernández's Mapocho: Spirits in a Material Wasteland

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Resha S Cardone

2015-01-01

Full Text Available This analysis of Mapocho (2002, a novel by Chilean writer and performer Nona Fernández, explores the significance of the author’s environmentalist representation of Chilean history as the accumulation of spiritual and material contaminants—ghosts and trash—that the victorious from throughout the country’s history have attempted to erase to further various economic and political agendas, particularly the neoliberal model installed during the Pinochet dictatorship. Fernández’s depiction of Chile as an ecological and spiritual wasteland in which the female protagonist (recollects, recycles and reuses the specters and detritus of past conflicts represents the author’s own literary project of advocating for human rights and environmental justice during the Chilean transition while modeling a way to counter the collective amnesia promoted under the newly established democracy.

Rhizospheric metagenome of the terrestrial mangrove fern Acrostichum from Indian Sunderbans

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Sayak Ganguli

2017-12-01

Full Text Available This study reports the analyses of the rhizospheric microbiome of the terrestrial mangrove fern Acrostichum aureum Linn. from the Indian Sunderbans. Samples were collected using standard protocols and 16S rRNA gene V3–V4 region amplicon sequencing was performed to identify the microbial communities prevalent in the rhizosphere. A total of 1,931,252 quality checked reads were assembled into 204,818 contigs and were analysed using QIIME to reveal the abundance of Proteobacteria, Acidobacteria and Planctomycetes. The data is available at the NCBI - Sequence Read Archive with accession number: SRX2660456. This is the first report of the rhizospheric microbiome belonging to a fern species.

Regeneration of forest phytocoenoses after various agricultural land use practices in the conditions of middle taiga subzone

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V. A. Karpin

2017-12-01

Full Text Available The process of forest cover regeneration after the cessation of human impact was considered. The study area was situated in the southern part of the Kenozersky National Park, Arkhangelsk Oblast. This area has 500 years of agricultural land use history. The territory features a complete spectrum of land at some point used for agricultural production: from sites currently in active use to fully recovered tree stands aged 120–140 years. The reforestation process was considered separately for each of the following land uses: slash-and-burn, multipurpose small-patch, and arable-grassland types, which differ considerably in impact intensity, duration, and degree of disturbance of the forest environment. The course of forest regeneration successions was found to depend on the type of preceding land use. The time required for the forest communities in slash-and-burn sites to recover to their original state is 120–140 years, and the succession involves the deciduous stage. Multipurpose small-patch use left the forest environment more profoundly modified. Eventually, a majority of these sites are now occupied by more productive, although undistinguishable from the original, coniferous-deciduous stands. Some factors have been detected that may lead to the formation in such sites of low-productivity self-regenerating plant communities dominated by deciduous species, which can persist there for an indefinitely long time unless relevant actions are taken. Arable-grassland land use considerably inhibits the regeneration of the forest cover typical of middle taiga, because there forms a thick sod layer. It was only in some grassland patches, where the impact stopped 5–10 years ago, that coniferous species, namely pine, were successfully regenerating.

Woodland: dynamics of average diameters of coniferous tree stands of the principal forest types

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R. A. Ziganshin

2016-08-01

Full Text Available The analysis of age dynamics of average diameters of deciduous tree stands of different forest types at Highland Khamar-Daban (natural woodland in South-East Baikal Lake region has been done. The aggregate data of average tree, the analysis of age dynamics of average diameters of a deciduous tree stands of stand diameters by age classes, as well as tree stand current periodic and overall average increment are presented and discussed in the paper. Forest management appraisal is done. The most representative forest types have been selected to be analyzed. There were nine of them including three Siberian stone pine Pinus sibirica Du Tour stands, three Siberian fir Abies sibirica Ledeb. stands, one Siberian spruce Picea obovata Ledeb. stand, and two dwarf Siberian pine Pinus pumila (Pallas Regel stands. The whole high-altitude range of mountain taiga has been evaluated. Mathematical and statistic indicators have been calculated for every forest type. Stone pine stands are the largest. Dynamics of mean diameters of forest stands have been examined by dominant species for every forest type. Quite a number of interesting facts have been elicited. Generally, all species have maximal values of periodic annual increment that is typical for young stands, but further decrease of increment is going on differently and connects to the different lifetime of wood species. It is curious that annual increment of the dwarf Siberian pine stands almost does not decrease with aging. As for mean annual increment, it is more stable than periodic annual increment. From the fifth age class (age of stand approaching maturity mean annual increment of cedar stands varies from 0.20 to 0.24 cm per year; from 0.12–0.15 to 0.18–0.21 cm per year – in fir stands; from 0.18 to 0.24 cm per year – in spruce stands; and from 0.02–0.03 to 0.05–0.06 cm per year – in draft pine stands. Mean annual increment of dwarf Siberian pine increases with aging and increment of other

The conversion of evenaged into unevenaged mixed conifer forests in southern British Columbia

Energy Technology Data Exchange (ETDEWEB)

Eichel, G.H.

1995-12-31

A detailed description of the conditions and history leading to the establishment and continuity of all-aged mixed coniferous forests in the montane south central region of British Columbia, Canada. Also described are the attempts by one forest products company to perpetuate and proportionally increase this type of forest cover through the selective removal necessitated by bark beetle depredation of the component, Pinus contorta. The report concludes with a description of and recommendations for the post-harvest management employing treatments which imitate natural conditions leading to a gradual and lasting conversion of natural multi-species stands into unevenaged or all-aged stands of mixed conifers which are conducive to single tree or group selection harvests at more or less regular intervals. 10 figs, 1 tab

Acidity of tree bark as a bioindicator of forest pollution in southern Poland

Energy Technology Data Exchange (ETDEWEB)

Grodznska, K

1976-01-01

PH values and buffering capacity were determined for bark samples of 5 deciduous trees (oak, alder, hornbeam, ash, linden), one shrub (hazel) and one coniferous tree (scots pine) in the Cracow industrial region (southern Poland) and for comparison in the Bialowieza Forest (north-eastern Poland). The correlation was found between acidification of tree bark and air pollution by SO/sub 2/ in these areas. All trees showed the least acidic reaction in the control area (Bialowieza Forest), more acidic in Niepolomice Forest and the most acidic in the center of Cracow city. The buffering capacity of the bark against alkali increased with increasing air pollution. The seasonal fluctuations of pH values is recommended as a sensitive and simple indicator of air pollution.

The conversion of evenaged into unevenaged mixed conifer forests in southern British Columbia

Energy Technology Data Exchange (ETDEWEB)

Eichel, G H

1996-12-31

A detailed description of the conditions and history leading to the establishment and continuity of all-aged mixed coniferous forests in the montane south central region of British Columbia, Canada. Also described are the attempts by one forest products company to perpetuate and proportionally increase this type of forest cover through the selective removal necessitated by bark beetle depredation of the component, Pinus contorta. The report concludes with a description of and recommendations for the post-harvest management employing treatments which imitate natural conditions leading to a gradual and lasting conversion of natural multi-species stands into unevenaged or all-aged stands of mixed conifers which are conducive to single tree or group selection harvests at more or less regular intervals. 10 figs, 1 tab

Retreating or standing: Responses of forest species and steppe species to climate change in arid eastern central Asia

Science.gov (United States)

Hong-Xiang Zhang; Ming-Li Zhang; Stewart C. Sanderson

2013-01-01

The temperature in arid Eastern Central Asia is projected to increase in the future, accompanied by increased variability of precipitation. To investigate the impacts of climate change on plant species in this area, we selected two widespread species as candidates, Clematis sibirica and C. songorica, from montane coniferous forest and arid steppe habitats respectively...

Seasonal Variability of Ground Water Levels in the Puszcza Zielonka Forest

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Grajewski Sylwester

2014-07-01

Full Text Available The paper presents results of studies on seasonal variability of ground water tables recorded in long-term observations of water levels in the Puszcza Zielonka forest complex. The Puszcza Zielonka Forest is located in the middle part of the Warta basin in the central part of the Wielkopolska region. Its western boundary is located approx. 6 km north-east of Poznań. The area is situated in the western part of the Wielkopolska-Mazovian climatic region. The natural landscape is of young glacial type of Pleistocene and Holocene formation. For this reason parent materials for soils in this area were mainly postglacial drifts, deposits coming from the Poznań stage of the Würm glaciation. In terms of granulometric composition these were mainly low clayey sands deposited on loose sands with an admixture of gravel and eroded sandy clay. Scots pine is the dominant species. Oaks, alders, larches and scarce spruces are also found in this area. Predominant sites include fresh mixed forest, fresh mixed coniferous forest, fresh broadleaved forest and alder swamp forest.

Extractability of 137Cs in Response to its Input Forms into Fukushima Forest Soils.

Science.gov (United States)

Mengistu, T. T.; Carasco, L.; Orjollet, D.; Coppin, F.

2017-12-01

In case of nuclear accidents like Fukushima disaster, the influence of 137Cs depositional forms (soluble and/or solid forms) on mineral soil of forest environment on its availability have not reported yet. Soluble (137Cs tagged ultra-pure water) and solid (137Cs contaminated litter-OL and fragmented litter-OF) input forms were mixed with the mineral soils collected under Fukushima coniferous and broadleaf forests. The mixtures then incubated under controlled laboratory condition to evaluate the extractability of 137Cs in soil over time in the presence of decomposition process through two extracting reagents- water and ammonium acetate. Results show that extracted 137Cs fraction with water was less than 1% for soluble input form and below detection limit for solid input form. On the same way with acetate reagent, the extracted 137Cs fraction ranged from 46 to 56% for soluble input and 2 to 15% for solid input, implying the nature of 137Cs contamination strongly influences the extractability and hence the mobility of 137Cs in soil. Although the degradation rate of the organic materials has been calculated in the range of 0.18 ± 0.1 to 0.24 ± 0.1 y-1, its impact on 137Cs extractability appeared very weak at least within the observation period, probably due to shorter time scale. Concerning the treatments of solid 137Cs input forms through acetate extraction, relatively more 137Cs has been extracted from broadleaf organic materials mixes (BL-OL & BL-OF) than the coniferous counterparts. This probably is due to the fact that the lignified coniferous organic materials (CED-OL & CED-OF) components tend to retain more 137Cs than that of the broadleaf. Generally, by extrapolating these observations in to a field context, one can expect more available 137Cs fraction in forest soil from wet depositional pathways such as throughfall and stemflow than those attached with organic materials like litter (OL) and its eco-processed forms (OF).

Detection and Characterization of Stress Symptoms in Forest Vegetation

Science.gov (United States)

Heller, R. C.

1971-01-01

Techniques used at the Pacific Southwest Forest and Range Experiment Station to detect advanced and previsual symptoms of vegetative stress are discussed. Stresses caused by bark beetles in coniferous stands of timber are emphasized because beetles induce stress more rapidly than most other destructive agents. Bark beetles are also the most damaging forest insects in the United States. In the work on stress symptoms, there are two primary objectives: (1) to learn the best combination of films, scales, and filters to detect and locate injured trees from aircraft and spacecraft, and (2) to learn if stressed trees can be detected before visual symptoms of decline occur. Equipment and techniques used in a study of the epidemic of the Black Hills bark beetle are described.

Radionuclides in forest ecosystems

International Nuclear Information System (INIS)

Strebl, F.; Bossew, P.; Kienzl, K.; Hiesel, E.

2000-01-01

Some regions within Austria were highly contaminated (> 50 kBq m -2 ) with radiocaesium by the deposition event following the Chernobyl reactor accident in 1986. Monitoring carried out by several Austrian institutions showed that in contrast to agricultural products radiocaesium levels in wild berries, mushrooms and game meat from forest ecosystems remained considerably higher over the years. To find reasons for this contrasting radioecological behavior and for the derivation of model input parameters, an extended study about the distribution of 137 Cs within three Austrian forest stands was carried out between 1987 and 1997. Results of this and subsequent studies are summarized and include the following ecosystem compartments: forest soils, litter, trees, bilberry, mushrooms, mosses, ferns, lichen, other vegetation, insects, small mammals, game animals and surface water. Besides the investigation of radioecological behavior an estimation of pool sizes and transfer rates as well as radioecological residence half times for 137 Cs in different forest species was used to compile a radiocaesium balance for the years 1988 and 1996. Soil proved to be an effective sink for radiocaesium contamination, but in long-term perspective it can act as a source for the contamination of vegetation and higher levels of the food-chain as well. Due to the high standing biomass trees represent the largest 'living' radiocaesium pool within the investigated forest stand. Dose estimations based on average consume habits gave no significant increase (less than 0.4 %) of the annual average population radiation dose due to the ingestion of forest products from the investigated forest stands. (author)

The colonisation of woodland gaps by ferns and horsetails

NARCIS (Netherlands)

Bremer, P.

2010-01-01

In the Voorsterbos, a planted woodland on a former sea-floor (the Netherlands), artificial gaps within stands of Fagus sylvatica on boulder clay were monitored for five or six years after cutting. Ten fern species and three species of horsetail established in these gaps, with Dryopteris cristata,

Mercury concentrations and pools in four adjacent coniferous and deciduous upland forests in Beijing, China

Science.gov (United States)

Zhou, Jun; Wang, Zhangwei; Zhang, Xiaoshan; Gao, Yu

2017-05-01

Understanding of forest mercury (Hg) pools is important for quantifying the global atmospheric Hg removal. We studied gaseous elemental Hg (GEM) concentrations, litterfall Hg depositions, and pool sizes in four adjacent stands at Mount Dongling to assess Hg dynamics in the forested catchment and the potential of Hg release during wildfires. The average GEM concentration was 2.5 ± 0.5 ng m-3, about 1.5 times of the background levels in the Northern Hemisphere. In all four stands, Hg concentrations increase in the following order: bole wood mineral soil litter < Oe soil < Oa organic soil. The Hg pools of aboveground biomass were comparable in the forests of larch, oak, and Chinese pine, which were much greater than that of mixed broadleaf stands due to lower biomass. The total Hg pools in ecosystems were similar in the four stands, because of the comparable Hg pool in the soil horizons (0-40 cm), which accounted for over 97% of the total ecosystem Hg storage in the four stands. Although Hg pools of the forest ecosystem in north China were comparable to North America and North Europe, Hg storage in forests constituted a high threat for large Hg emission pulses to the atmosphere by wildfires. The potential Hg emissions from the combustion at the four stands were ranged from 0.675 to 1.696 mg m-2.

Mitigating arsenic contamination in rice plants with an aquatic fern, Marsilea minuta.

Science.gov (United States)

Hassi, Ummehani; Hossain, Md Tawhid; Huq, S M Imamul

2017-10-10

Dangers of arsenic contamination are well known in human civilization. The threat increases when arsenic is accumulated in food and livestock through irrigated crops or animal food. Hence, it is important to mitigate the effects of arsenic as much as possible. This paper discusses a process for reducing the level of arsenic in different parts of rice plants with an aquatic fern, Marsilea minuta L. A pot experiment was done to study the possibility of using Marsilea minuta as a phytoremediator of arsenic. Rice and Marsilea minuta were allowed to grow together in soils. As a control, Marsilea minuta was also cultured alone in the presence and absence of arsenic (applied at 1 mg/L as irrigation water). We did not find any significant change in the growth of rice due to the association of Marsilea minuta, though it showed a reduction of approximately 58.64% arsenic accumulation in the roots of rice grown with the association of fern compared to that grown without fern. We measured a bioaccumulation factor (BF) of > 5.34, indicating that Marsilea minuta could be a good phytoremediator of arsenic in rice fields.

Life-history traits maintain the genomic integrity of sympatric species of the spruce budworm (Choristoneura fumiferana) group on an isolated forest island

Science.gov (United States)

Lisa M. Lumley; Felix A.H. Sperling

2011-01-01

Identification of widespread species collected from islands can be challenging due to the potential for local ecological and phenotypic divergence in isolated populations. We sought to determine how many species of the spruce budworm (Choristoneura fumiferana) complex reside in Cypress Hills, an isolated remnant coniferous forest in western Canada....

[Syntaxonomic analysis of restorative successions after cutting down light coniferous forests of South Ural Region].

Science.gov (United States)

Martynenko, V B; Shirokhikh, P S; Mirkin, B M; Naumova, L G

2014-01-01

Discussed are the possibilities of using syntaxa from floristic classification for the analysis of secondary restorative successions after forest cutting in South Ural Region. Peculiarities of secondary forest communities classification that may be viewed as subjects of indigenous vegetation syntaxa forming, sub-associations or could be systematized according to 'deductive' classification introduced by K. Kopecky and S. Heiny are considered. An example is presented of an analysis of communities succession system formed after cutting down hemiboreal pine and birch-pine herbaceous forests of Bupleuro-Pinetum association. Within this system the processes of divergence and convergence of succession series take place. Divergence occur as a result of lifting of the influence caused by dominants edificating role and manifestation of differences in soil humidification, also as a consequence of soil enrichment by mineral elements after burning down the felling debris. The reason behind convergence is grading influence of renewed forest stand. Trends in species richness changes during restorative successions may differ depending on ecotope features. In course of a succession, models of tolerance and inhibition become apparent.

Instructions for collecting tree ferns of the family Cyatheaceae

NARCIS (Netherlands)

Holttum, R.E.

1957-01-01

The next monographic study which will be undertaken for the series Pteridophyta of the Flora Malesiana will be devoted to the tree ferns of the Cyatheaceae. In connection with the large size of these plants and the desirability of having more and complete material at our disposal, the following

Coarse woody debris carbon storage across a mean annual temperature gradient in tropical montane wet forest

Science.gov (United States)

Darcey K. Iwashita; Creighton M. Litton; Christian P. Giardina

2013-01-01

Coarse woody debris (CWD; defined here as fallen and standing dead trees and tree ferns) is a critical structural and functional component of forest ecosystems that typically comprises a large proportion of total aboveground carbon (C) storage. However, CWD estimates for the tropics are uncommon, and little is known about how C storage in CWD will respond to climate...

Conservation assessment for the autumn willow in the Black Hills National Forest, South Dakota and Wyoming

Science.gov (United States)

J. Hope Hornbeck; Carolyn Hull Sieg; Deanna J. Reyher

2003-01-01

Autumn willow, Salix serissima (Bailey) Fern., is an obligate wetland shrub that occurs in fens and bogs in the northeastern United States and eastern Canada. Disjunct populations of autumn willow occur in the Black Hills of South Dakota. Only two populations occur on Black Hills National Forest lands: a large population at McIntosh Fen and a small...

Native and exotic plant cover vary inversely along a climate gradient 11 years following stand-replacing wildfire in a dry coniferous forest, Oregon, USA.

Science.gov (United States)

Dodson, Erich K; Root, Heather T

2015-02-01

Community re-assembly following future disturbances will often occur under warmer and more moisture-limited conditions than when current communities assembled. Because the establishment stage is regularly the most sensitive to climate and competition, the trajectory of recovery from disturbance in a changing environment is uncertain, but has important consequences for future ecosystem functioning. To better understand how ongoing warming and rising moisture limitation may affect recovery, we studied native and exotic plant composition 11 years following complete stand-replacing wildfire in a dry coniferous forest spanning a large gradient in climatic moisture deficit (CMD) from warm and dry low elevation sites to relatively cool and moist higher elevations sites. We then projected future precipitation, temperature and CMD at our study locations for four scenarios selected to encompass a broad range of possible future conditions for the region. Native perennials dominated relatively cool and moist sites 11 years after wildfire, but were very sparse at the warmest and driest (high CMD) sites, particularly when combined with high topographic sun exposure. In contrast, exotic species (primarily annual grasses) were dominant or co-dominant at the warmest and driest sites, especially with high topographic sun exposure. All future scenarios projected increasing temperature and CMD in coming decades (e.g., from 4.5% to 29.5% higher CMD by the 2080's compared to the 1971-2000 average), even in scenarios where growing season (May-September) precipitation increased. These results suggest increasing temperatures and moisture limitation could facilitate longer term (over a decade) transitions toward exotic-dominated communities after severe wildfire when a suitable exotic seed source is present. © 2014 John Wiley & Sons Ltd.

Wing stridulation in a Jurassic katydid (Insecta, Orthoptera) produced low-pitched musical calls to attract females.

Science.gov (United States)

Gu, Jun-Jie; Montealegre-Z, Fernando; Robert, Daniel; Engel, Michael S; Qiao, Ge-Xia; Ren, Dong

2012-03-06

Behaviors are challenging to reconstruct for extinct species, particularly the nature and origins of acoustic communication. Here we unravel the song of Archaboilus musicus Gu, Engel and Ren sp. nov., a 165 million year old stridulating katydid. From the exceptionally preserved morphology of its stridulatory apparatus in the forewings and phylogenetic comparison with extant species, we reveal that A. musicus radiated pure-tone (musical) songs using a resonant mechanism tuned at a frequency of 6.4 kHz. Contrary to previous scenarios, musical songs were an early innovation, preceding the broad-bandwidth songs of extant katydids. Providing an accurate insight into paleoacoustic ecology, the low-frequency musical song of A. musicus was well-adapted to communication in the lightly cluttered environment of the mid-Jurassic forest produced by coniferous trees and giant ferns, suggesting that reptilian, amphibian, and mammalian insectivores could have also heard A. musicus' song.

Divergence of dominant factors in soil microbial communities and functions in forest ecosystems along a climatic gradient

Science.gov (United States)

Xu, Zhiwei; Yu, Guirui; Zhang, Xinyu; He, Nianpeng; Wang, Qiufeng; Wang, Shengzhong; Xu, Xiaofeng; Wang, Ruili; Zhao, Ning

2018-03-01

Soil microorganisms play an important role in regulating nutrient cycling in terrestrial ecosystems. Most of the studies conducted thus far have been confined to a single forest biome or have focused on one or two controlling factors, and few have dealt with the integrated effects of climate, vegetation, and soil substrate availability on soil microbial communities and functions among different forests. In this study, we used phospholipid-derived fatty acid (PLFA) analysis to investigate soil microbial community structure and extracellular enzymatic activities to evaluate the functional potential of soil microbes of different types of forests in three different climatic zones along the north-south transect in eastern China (NSTEC). Both climate and forest type had significant effects on soil enzyme activities and microbial communities with considerable interactive effects. Except for soil acid phosphatase (AP), the other three enzyme activities were much higher in the warm temperate zone than in the temperate and the subtropical climate zones. The soil total PLFAs and bacteria were much higher in the temperate zone than in the warm temperate and the subtropical zones. The soil β-glucosidase (BG) and N-acetylglucosaminidase (NAG) activities were highest in the coniferous forest. Except for the soil fungi and fungi-bacteria (F/B), the different groups of microbial PLFAs were much higher in the conifer broad-leaved mixed forests than in the coniferous forests and the broad-leaved forests. In general, soil enzyme activities and microbial PLFAs were higher in primary forests than in secondary forests in temperate and warm temperate regions. In the subtropical region, soil enzyme activities were lower in the primary forests than in the secondary forests and microbial PLFAs did not differ significantly between primary and secondary forests. Different compositions of the tree species may cause variations in soil microbial communities and enzyme activities. Our results

[Carbon storage of forest stands in Shandong Province estimated by forestry inventory data].

Science.gov (United States)

Li, Shi-Mei; Yang, Chuan-Qiang; Wang, Hong-Nian; Ge, Li-Qiang

2014-08-01

Based on the 7th forestry inventory data of Shandong Province, this paper estimated the carbon storage and carbon density of forest stands, and analyzed their distribution characteristics according to dominant tree species, age groups and forest category using the volume-derived biomass method and average-biomass method. In 2007, the total carbon storage of the forest stands was 25. 27 Tg, of which the coniferous forests, mixed conifer broad-leaved forests, and broad-leaved forests accounted for 8.6%, 2.0% and 89.4%, respectively. The carbon storage of forest age groups followed the sequence of young forests > middle-aged forests > mature forests > near-mature forests > over-mature forests. The carbon storage of young forests and middle-aged forests accounted for 69.3% of the total carbon storage. Timber forest, non-timber product forest and protection forests accounted for 37.1%, 36.3% and 24.8% of the total carbon storage, respectively. The average carbon density of forest stands in Shandong Province was 10.59 t x hm(-2), which was lower than the national average level. This phenomenon was attributed to the imperfect structure of forest types and age groups, i. e., the notably higher percentage of timber forests and non-timber product forest and the excessively higher percentage of young forests and middle-aged forest than mature forests.

Changes in Biomass Carbon and Soil Organic Carbon Stocks following the Conversion from a Secondary Coniferous Forest to a Pine Plantation.

Directory of Open Access Journals (Sweden)

Shuaifeng Li

Full Text Available The objectives of this study were to estimate changes of tree carbon (C and soil organic carbon (SOC stock following a conversion in land use, an issue that has been only insufficiently addressed. For this study, we examined a chronosequence of 2 to 54-year-old Pinus kesiya var. langbianensis plantations that replaced the original secondary coniferous forest (SCF in Southwest China due to clearing. C stocks considered here consisted of tree, understory, litter, and SOC (0-1 m. The results showed that tree C stocks ranged from 0.02±0.001 Mg C ha-1 to 141.43±5.29 Mg C ha-1, and increased gradually with the stand age. Accumulation of tree C stocks occurred in 20 years after reforestaion and C stock level recoverd to SCF. The maximum of understory C stock was found in a 5-year-old stand (6.74±0.7 Mg C ha-1 with 5.8 times that of SCF, thereafter, understory C stock decreased with the growth of plantation. Litter C stock had no difference excluding effects of prescribed burning. Tree C stock exhibited a significant decline in the 2, 5-year-old stand following the conversion to plantation, but later, increased until a steady state-level in the 20, 26-year-old stand. The SOC stocks ranged from 81.08±10.13 Mg C ha-1 to 160.38±17.96 Mg C ha-1. Reforestation significantly decreased SOC stocks of plantation in the 2-year-old stand which lost 42.29 Mg C ha-1 in the 1 m soil depth compared with SCF by reason of soil disturbance from sites preparation, but then subsequently recovered to SCF level. SOC stocks of SCF had no significant difference with other plantation. The surface profile (0-0.1 m contained s higher SOC stocks than deeper soil depth. C stock associated with tree biomass represented a higher proportion than SOC stocks as stand development proceeded.

Forest harvesting reduces the soil metagenomic potential for biomass decomposition.

Science.gov (United States)

Cardenas, Erick; Kranabetter, J M; Hope, Graeme; Maas, Kendra R; Hallam, Steven; Mohn, William W

2015-11-01

Soil is the key resource that must be managed to ensure sustainable forest productivity. Soil microbial communities mediate numerous essential ecosystem functions, and recent studies show that forest harvesting alters soil community composition. From a long-term soil productivity study site in a temperate coniferous forest in British Columbia, 21 forest soil shotgun metagenomes were generated, totaling 187 Gb. A method to analyze unassembled metagenome reads from the complex community was optimized and validated. The subsequent metagenome analysis revealed that, 12 years after forest harvesting, there were 16% and 8% reductions in relative abundances of biomass decomposition genes in the organic and mineral soil layers, respectively. Organic and mineral soil layers differed markedly in genetic potential for biomass degradation, with the organic layer having greater potential and being more strongly affected by harvesting. Gene families were disproportionately affected, and we identified 41 gene families consistently affected by harvesting, including families involved in lignin, cellulose, hemicellulose and pectin degradation. The results strongly suggest that harvesting profoundly altered below-ground cycling of carbon and other nutrients at this site, with potentially important consequences for forest regeneration. Thus, it is important to determine whether these changes foreshadow long-term changes in forest productivity or resilience and whether these changes are broadly characteristic of harvested forests.

Use of rbcL and trnL-F as a two-locus DNA barcode for identification of NW-European ferns: an ecological perspective

NARCIS (Netherlands)

Groot, de G.A.; During, H.J.; Maas, J.W.; Schneider, H.; Erkens, R.H.J.

2011-01-01

Although consensus has now been reached on a general two-locus DNA barcode for land plants, the selected combination of markers (rbcL + matK) is not applicable for ferns at the moment. Yet especially for ferns, DNA barcoding is potentially of great value since fern gametophytes—while playing an

Screening for Ptaquiloside in Ferns: Using Herbarium Specimens for Qualitative Mapping Purposes.

Science.gov (United States)

Rasmussen, Lars Holm; Pedersen, Henrik AErenlund

2017-11-01

Ptaquiloside (PTA) is a noxious carcinogen found widespread in Bracken (Pteridium sp.) but with scattered and unresolved distribution outside the genus. The carcinogen causes Bovine Enzootic Haematuria among cattle all-over the World and is under suspicion of causing human cancers. To set-up a methodology for large-scale qualitative studies on the distribution of PTA in ferns using already available herbarium specimens as source. PTA and the main degradation product pterosin B (PtB) were quantified in aqueous frond extracts by HPLC-DAD. PTA was quantified after forced reaction into PtB. Optimal reaction conditions were tested using hydrochloric acid, sulphuric acid, trifluoroacetic acid (TFA), acetic acid and temperature as the experimental variables. A pair-wise test for PTA degradation in plant-press were used to explore the effect of this preservation regime. A selection of up to 50 years old Bracken herbarium specimens were tested for PTA and PtB. The methodology was applied on 21 fern species from Denmark. An optimised TFA-based method results in 30.7% higher conversion and a 1:1 reaction between PTA and PtB. Full three-dimensional resolution of the analyte was obtained. Preservation of fronds in a plant press increase formation of PtB. Hence, the method is only suitable for qualitative studies. Presence of PTA and PtB were found in samples up to 50 years old. Among 21 ferns tested, the compounds were only found in Pteridium aquilinum. Herbarium specimens up to 50 years old can be used for explorative risk assessment of ferns using HPLC-DAD for quantification and identification. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

Functional screening of abundant bacteria from acidic forest soil indicates the metabolic potential of Acidobacteria subdivision 1 for polysaccharide decomposition

Czech Academy of Sciences Publication Activity Database

Lladó, Salvador; Žifčáková, Lucia; Větrovský, Tomáš; Eichlerová, Ivana; Baldrian, Petr

2016-01-01

Roč. 52, č. 2 (2016), s. 251-260 ISSN 0178-2762 R&D Projects: GA ČR(CZ) GP14-09040P EU Projects: European Commission(CZ) FP7ITN no.289949 Institutional support: RVO:61388971 Keywords : Coniferous forest * Bacterial ecology * Acidobacteria Subject RIV: EE - Microbiology, Virology Impact factor: 3.683, year: 2016

The omnipresent water fern Azolla caroliniana does not contain lignin

NARCIS (Netherlands)

Nierop, K.G.J.; Speelman, E.N.; Leeuw, J.W. de; Reichart, G.-J.

2011-01-01

Several studies have reported the presence of large amounts of lignin in ubiquitously occurring species of the freshwater fern Azolla. Molecular analysis using flash pyrolysis and thermally assisted hydrolysis and methylation shows, however, that neither the leaves nor the roots of Azolla contain

Environmental Fate and Analysis of Ptaquiloside from the Bracken Fern

DEFF Research Database (Denmark)

Clauson-Kaas, Frederik

The naturally occurring phytotoxin ptaquiloside (PTA) has long been known to be both acute toxic and carcinogenic. Contents of more than 1% ptaquiloside on dry weight has been detected in bracken (Pteridium spp.), a fern distributed across the globe in often dense populations. This work focused...... on the fate of PTA in the soil-water system, from where it may leach to drinking water sources. PTA was detected in concentrations up to 2.2 µg/L in natural waters receiving drainage from bracken populations, and was found in both surface and groundwater. It was shown that ptaquiloside leached off bracken...... fronds (the leaves of ferns) in concentrations up to 169 µ/L during rainfall events. Rainfall further determined the concentration in a stream that drained a bracken-covered catchment, suggesting that this is a potent driver of ptaquiloside exposure in the environment. In both pure and natural waters, p...

Acidity of tree bark as a bioindicator of forest pollution in southern Poland

Energy Technology Data Exchange (ETDEWEB)

Grodzinska, K

1977-05-01

pH values and buffering capacity were determined for bark samples of five deciduous trees (oak, alder, hornbeam, ash, linden), one shrub (hazel) and one coniferous tree (scots pine) in the Cracow Industrial Region (southern Poland) and, for comparison, in the Bialowieza Forest (northeastern Poland). The correlation was found between acidification of tree bark and air pollution by SO/sub 2/ in these areas. All trees showed the least acidic reaction in the control area (Bialowieza Forest), more acidic in Niepolomice Forest and the most acidic in the center of Cracow. The buffering capacity of the bark against alkali increased with increasing air pollution. The seasonal fluctuations of pH values and buffering capacity were found. Tree bark is recommended as a sensitive and simple indicator of air pollution.

Global biogeography of scaly tree ferns (Cyatheaceae): evidence for Gondwanan vicariance and limited transoceanic dispersal

OpenAIRE

Korall, Petra; Pryer, Kathleen

2014-01-01

Aim Scaly tree ferns, Cyatheaceae, are a well-supported group of mostly tree-forming ferns found throughout the tropics, the subtropics and the south-temperate zone. Fossil evidence shows that the lineage originated in the Late Jurassic period. We reconstructed large-scale historical biogeographical patterns of Cyatheaceae and tested the hypothesis that some of the observed distribution patterns are in fact compatible, in time and space, with a vicariance scenario related to the break-up of G...

The spatial distribution of forest damages in southeastern Finland

Energy Technology Data Exchange (ETDEWEB)

Jokinen, J.; Maekinen, E.; Meinander, O.; Haarala, S. [Finnish Meteorological Inst., Helsinki (Finland)

1995-12-31

Up to the present time scientists researching the causes of the vast areas of forest damages observed in Europe and North America have presented many different hypotheses. Among the first explanations was the damaging effect of acid rain. Some researchers claimed that of all air pollutants ozone was the most important damaging agent. The stress theory emphasizes the interaction of nitrogen oxides and sulphur dioxide with oxidants, hydrocarbons and heavy metals to be the main cause of toxic effects. In addition to above-mentioned theories, projects carried out by the Finnish Meteorological Institute (FMI) have revealed that under northern conditions coniferous forests have been damaged even in situations where the emissions consist of sulphur and nitrogen compounds occurring together. This theory postulates that the interaction of the above pollutants may be responsible by themselves for the effects on coniferous forests. The interaction is supposed to cause damages by two different mechanisms, namely, by causing direct toxic effects or through wintering failures. These mechanisms are indicated by the total nitrogen and sulphur concentration relationships of the needles. In the first case both sulphur dioxide and nitrogen oxides occur at such a high levels in the air that they cause direct damages, while in the second case sulphur dioxide concentration, in particular, is lower and both compounds can then be used as nutrients causing nutrient imbalance and a loss of wintering hardiness of the needles. The study area in these projects was southeastern Finland, which is one of the most polluted areas in our country. Domestic emissions from the paper and pulp industry, as well as the Russian emissions (e g. from the Leningrad region) affect this area. The aim of this study was to test the sulphur-nitrogen hypothesis using data collected from the Kymi province, S.E. Finland. (author)

The spatial distribution of forest damages in southeastern Finland

Energy Technology Data Exchange (ETDEWEB)

Jokinen, J; Maekinen, E; Meinander, O; Haarala, S [Finnish Meteorological Inst., Helsinki (Finland)

1996-12-31

Up to the present time scientists researching the causes of the vast areas of forest damages observed in Europe and North America have presented many different hypotheses. Among the first explanations was the damaging effect of acid rain. Some researchers claimed that of all air pollutants ozone was the most important damaging agent. The stress theory emphasizes the interaction of nitrogen oxides and sulphur dioxide with oxidants, hydrocarbons and heavy metals to be the main cause of toxic effects. In addition to above-mentioned theories, projects carried out by the Finnish Meteorological Institute (FMI) have revealed that under northern conditions coniferous forests have been damaged even in situations where the emissions consist of sulphur and nitrogen compounds occurring together. This theory postulates that the interaction of the above pollutants may be responsible by themselves for the effects on coniferous forests. The interaction is supposed to cause damages by two different mechanisms, namely, by causing direct toxic effects or through wintering failures. These mechanisms are indicated by the total nitrogen and sulphur concentration relationships of the needles. In the first case both sulphur dioxide and nitrogen oxides occur at such a high levels in the air that they cause direct damages, while in the second case sulphur dioxide concentration, in particular, is lower and both compounds can then be used as nutrients causing nutrient imbalance and a loss of wintering hardiness of the needles. The study area in these projects was southeastern Finland, which is one of the most polluted areas in our country. Domestic emissions from the paper and pulp industry, as well as the Russian emissions (e g. from the Leningrad region) affect this area. The aim of this study was to test the sulphur-nitrogen hypothesis using data collected from the Kymi province, S.E. Finland. (author)

Tatra's forests will recover from catastrophe for decades

International Nuclear Information System (INIS)

Haluza, I.

2004-01-01

Windy tornado in Tatra's national park (TANAP, High Tatras, Slovakia) at the end of 2004 caused extensive ecological catastrophe and economic losses. Wind has totally damaged the trees in more than one fourth of forest area, which is administrated by state forests of TANAP. Next fourth of forest area has impaired structure. Mostly coniferous forests have fallen down not only in High Tatras, but also in Horehronie, Kysuce, Orava and Spis. According to estimates around 2.5 million cubic meters of wood have lain on the ground in High Tatras. This wood must be precipitately processed. In another regions totally from 800 to 900 thousands cubic meters are overcame by wind. Ecological catastrophe has come in High Tatras. Totally damaged large forests areas need to be recovered for long decades. 90 per cent of annual Slovakian wood cutting represents totally 2.5 million cubic meters. The state will invest in forest recovery from sale of calamity stuff. Reforestation of one hectare of forest costs from 80 to 90 thousands Slovak crowns (∼2666-3000 USD). Another remedies at the age to five years represent from 40 to 50 thousands Slovak crowns (1333-16666 USD). Around 1.6 billion Slovak crown (∼53.333 million USD) will be needed for reforestation of 12 thousands hectares of TANAP

Neoendemism in Madagascan scaly tree ferns results from recent, coincident diversification bursts.

Science.gov (United States)

Janssen, Thomas; Bystriakova, Nadia; Rakotondrainibe, France; Coomes, David; Labat, Jean-Noël; Schneider, Harald

2008-08-01

More than 80% of Madagascar's 12,000 plant species are endemic with the degree of endemism reaching as much as 95% in the scaly tree ferns, an important species rich component of Madagascar's evergreen rainforests. Predominantly African or Asian ancestry and divergence times usually postdating the separation of Madagascar from the Gondwanan landmasses have been demonstrated for several Madagascan animal and angiosperm groups. However, evolutionary studies of rainforest-specific lineages are scarce and the ecological context of radiation events has rarely been investigated. Here, we examine the evolution of Madagascan tree ferns as a rainforest-specific model family, integrate results from bioclimatic niche analysis with a dated phylogenetic framework, and propose an evolutionary scenario casting new light on our knowledge of the evolution of large island endemic clades. We show that Madagascar's extant tree fern diversity springs from three distinct ancestors independently colonizing Madagascar in the Miocene and that these three monophyletic clades diversified in three coincident radiation bursts during the Pliocene, reaching exceptionally high diversification rates and most likely responding to a common climatic trigger. Recent diversification bursts may thus have played a major role in the evolution of the extant Madagascan rainforest biome, which hence contains a significant number of young, neoendemic taxa.

Climate change effects on vegetation in the Pacific Northwest: a review and synthesis of the scientific literature and simulation model projections

Science.gov (United States)

David W. Peterson; Becky K. Kerns; Erich Kyle Dodson

2014-01-01

The purpose of this study was to review scientifi c knowledge and model projections on vegetation vulnerability to climatic and other environmental changes in the Pacifi c Northwest, with emphasis on fi ve major biome types: subalpine forests and alpine meadows, maritime coniferous forests, dry coniferous forests, savannas and woodlands (oak and juniper), and interior...

Soil seed banks along elevational gradients in tropical, subtropical and subalpine forests in Yunnan Province, southwest China

Institute of Scientific and Technical Information of China (English)

Xiaqin Luo; Min Cao; Min Zhang; Xiaoyang Song; Jieqiong Li; Akihiro Nakamura; Roger Kitching

2017-01-01

Soil seed banks are a vital part of ecosystems and influence community dynamics and regeneration.Although soil seed banks in different habitats have been reported,how soil seed banks vary with elerational gradients in different climatic zones is still unknown.This paper investigates seed density,species composition and nonconstituent species of forest soil seed banks in Yunnan Province,southwest China.Similarity between the soil seed bank and standing vegetation was also examined.We collected soil samples from sites spanning 12 elevations in tropical rain forests,subtropical evergreen broadleaved forests and subalpine coniferous forests,and transported them to a glasshouse for germination trials for species identification.The soil seed banks of tropical and subtropical forests had much higher seed densities and species richness than those of subalpine forests.Seeds of woody species dominated the soil seed banks of tropical and subtropical forests,while herbs dominated those of subalpine forests.The nonconstituent species in the soil seed banks were all herbs and were most abundant in tropical forests,followed by subtropical forests but were completely absent from subalpine forests.

Soil seed banks along elevational gradients in tropical, subtropical and subalpine forests in Yunnan Province, southwest China

Directory of Open Access Journals (Sweden)

Xiaqin Luo

2017-10-01

Full Text Available Soil seed banks are a vital part of ecosystems and influence community dynamics and regeneration. Although soil seed banks in different habitats have been reported, how soil seed banks vary with elevational gradients in different climatic zones is still unknown. This paper investigates seed density, species composition and nonconstituent species of forest soil seed banks in Yunnan Province, southwest China. Similarity between the soil seed bank and standing vegetation was also examined. We collected soil samples from sites spanning 12 elevations in tropical rain forests, subtropical evergreen broad-leaved forests and subalpine coniferous forests, and transported them to a glasshouse for germination trials for species identification. The soil seed banks of tropical and subtropical forests had much higher seed densities and species richness than those of subalpine forests. Seeds of woody species dominated the soil seed banks of tropical and subtropical forests, while herbs dominated those of subalpine forests. The nonconstituent species in the soil seed banks were all herbs and were most abundant in tropical forests, followed by subtropical forests but were completely absent from subalpine forests.

Manganese availability is negatively associated with carbon storage in northern coniferous forest humus layers.

Science.gov (United States)

Stendahl, Johan; Berg, Björn; Lindahl, Björn D

2017-11-14

Carbon sequestration below ground depends on organic matter input and decomposition, but regulatory bottlenecks remain unclear. The relative importance of plant production, climate and edaphic factors has to be elucidated to better predict carbon storage in forests. In Swedish forest soil inventory data from across the entire boreal latitudinal range (n = 2378), the concentration of exchangeable manganese was singled out as the strongest predictor (R 2  = 0.26) of carbon storage in the extensive organic horizon (mor layer), which accounts for one third of the total below ground carbon. In comparison, established ecosystem models applied on the same data have failed to predict carbon stocks (R 2  < 0.05), and in our study manganese availability overshadowed both litter production and climatic factors. We also identified exchangeable potassium as an additional strong predictor, however strongly correlated with manganese. The negative correlation between manganese and carbon highlights the importance of Mn-peroxidases in oxidative decomposition of recalcitrant organic matter. The results support the idea that the fungus-driven decomposition could be a critical factor regulating humus carbon accumulation in boreal forests, as Mn-peroxidases are specifically produced by basidiomycetes.

Plant-cover influence on the spatial distribution of radiocaesium deposits in forest ecosystems

International Nuclear Information System (INIS)

Guillitte, Olivier; Andolina, Jean; Koziol, Michel; Debauche, Antoine

1990-01-01

Since the Chernobyl nuclear accident, a major campaign of radioactive deposit measurements has been carried out on forest soils in Belgium and the Grand Duchy of Luxemburg. Three types of forest ecosystems have systematically been taken into account in each region: coniferous forests (mainly spruce stands), deciduous forests (mainly beech stands) and in clearings. Sampling and field measurements have been carried out in different places with regard to the plant cover: near the trunks, under the foliage, in a small gap, on soil with or without herbaceous or moss stratum. The samples have been collected and measured according to the different recognizable soil layers in order to evaluate the vertical deposit distribution. From overall measurements, one may observe a high spatial soil deposit variation which is mainly explained by the nature, structure and age of the forest stands and by the thickness and the nature of holorganic horizons. A particular interest of this study is the identification of the influence of stem flow and impluvium on forest-cover gaps and edges. (author)

Water migration of macroelements in coniferous-broad-leaved forests of Sikhote-Alin

OpenAIRE

N. K. Kozhevnikova; T. N. Lutsenko; A. G. Boldeskul; S. Yu. Lupakov; V. V. Shamov

2017-01-01

In the paper, the natural water chemical composition spatial variability studies results in the mountain forest catchment are presented. It’s shown that the catchment biotic components’ impact upon water chemical composition is detected even at input as atmospheric precipitation. The input fluxes are acid, sulfate ones with high ratio of hydrogen, potassium and dissolved organic matter. Diversity of ecotopic conditions determines the further transformation of natural water chemical composit...

Radiocaesium levels in roe deer and wild boar in two large forest areas in Austria

International Nuclear Information System (INIS)

Tataruch, F.; Klansek, E.; Schoenhofer, F.

1996-01-01

A report is given on the course of radiocaesium contamination in roe deer and wild boar in two large forest areas in Austria. In autumn 1987 and winter 1987/88 radiocaesium levels rose to values higher than those recorded in 1986 in these regions. The reason for this increase was the very specific feeding selection of roe deer in these forest areas resulting in the ingestion of an unusual high amount of blueberries, ferns and mushrooms. An explanation for the changes of wild boar's contamination has not been found yet, but possible reasons are discussed. (author)

Blueberries (Vaccinium myrtillus) as an indicator of radioactive pollution of a forest ecosystem

International Nuclear Information System (INIS)

Kienzl, K.; Hiesel, E.; Henrich, E.

1992-01-01

It was the aim of this project to find indicators within the forest ecosystem for pollution with artificial radionuclides. In the first line, the reference nuclide Cs-137 was examined. These biological indicators could be used quickly and comprehensively for analysis in the case of a possible repeated large-area contamination. In addition to mosses, lichens, ferns, various grasses, spruce needles, bark and wood, in particular bilberrry shrubs (Vaccinium myrtillus) were sampled repeatedly. The bilberry offers itself as a possible indicator plant (high incidence in the entire Austrian federal territory, simple sampling, deer feeding plant) and is also important as forest fruit for humans. (orig./EF) [de

Is there foul play in the leaf pocket? The metagenome of floating fern Azolla reveals endophytes that do not fix N2 but may denitrify.

Science.gov (United States)

Dijkhuizen, Laura W; Brouwer, Paul; Bolhuis, Henk; Reichart, Gert-Jan; Koppers, Nils; Huettel, Bruno; Bolger, Anthony M; Li, Fay-Wei; Cheng, Shifeng; Liu, Xin; Wong, Gane Ka-Shu; Pryer, Kathleen; Weber, Andreas; Bräutigam, Andrea; Schluepmann, Henriette

2018-01-01

Dinitrogen fixation by Nostoc azollae residing in specialized leaf pockets supports prolific growth of the floating fern Azolla filiculoides. To evaluate contributions by further microorganisms, the A. filiculoides microbiome and nitrogen metabolism in bacteria persistently associated with Azolla ferns were characterized. A metagenomic approach was taken complemented by detection of N 2 O released and nitrogen isotope determinations of fern biomass. Ribosomal RNA genes in sequenced DNA of natural ferns, their enriched leaf pockets and water filtrate from the surrounding ditch established that bacteria of A. filiculoides differed entirely from surrounding water and revealed species of the order Rhizobiales. Analyses of seven cultivated Azolla species confirmed persistent association with Rhizobiales. Two distinct nearly full-length Rhizobiales genomes were identified in leaf-pocket-enriched samples from ditch grown A. filiculoides. Their annotation revealed genes for denitrification but not N 2 -fixation. 15 N 2 incorporation was active in ferns with N. azollae but not in ferns without. N 2 O was not detectably released from surface-sterilized ferns with the Rhizobiales. N 2 -fixing N. azollae, we conclude, dominated the microbiome of Azolla ferns. The persistent but less abundant heterotrophic Rhizobiales bacteria possibly contributed to lowering O 2 levels in leaf pockets but did not release detectable amounts of the strong greenhouse gas N 2 O. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

Forecast for the dynamics of forests in Krasnoyarsk Krai

Directory of Open Access Journals (Sweden)

V. A. Sokolov

2017-08-01

Full Text Available Dynamics of the forest ecosystems connects closely with the natural and anthropogenic changes (succession processes, forest fires, windfalls, forest insects, forest diseases, forest harvesting, reforestation, the infrastructure development associated and not associated with forestry and so forth. Authors do not consider the up-to-day problem of global warming on the Earth, as opinions of scientists are controversial. Retrospective analysis of forest dynamics of the Krasnoyarsk Territory for the last 50 years has allowed to assess the impact of these changes on condition of forests. The univocal conclusion of deterioration of forest quality has been drawn. Area of coniferous forests has decreased by 9 %, including the 25 % reduction of mature and overmature forest stands. To forecast forest dynamics, modelling of natural and anthropogenic processes in the forest ecosystems has been applied, taking into account that the existing system of measures for reforestation and tending care of forest actually does not affect dynamics of the forests. The provision about increase in forest harvesting volume to 37.6 million м3 of the Development Strategy of the Krasnoyarsk Forest Industrial Complex has been used for forecasting. It has been proved that such scale of forest harvesting will inevitably lead to the over-cutting of ecological and economic accessible allowable cut that will negatively affect the forest condition in 50 years. Our forecast of forest dynamics of the Krasnoyarsk Territory for the next 50 years has showed that negative changes will continue at the same pace under the current extensive form of forest management. What is more, the maximum decrease of forest area might be in pine forests (32.9 % with the significant increase of broadleaves forests – 22.7 %. To improve the situation in the Russian forest sector, a radical change in the system of forest management is needed.

Evaluating UAV and LiDAR Retrieval of Snow Depth in a Coniferous Forest in Arizona

Science.gov (United States)

Van Leeuwen, W. J. D.; Broxton, P.; Biederman, J. A.

2017-12-01

Remote sensing of snow depth and cover in forested environments is challenging. Trees interfere with the remote sensing of snowpack below the canopy and cause large variations in the spatial distribution of the snowpack itself (e.g. between below canopy environments to shaded gaps to open clearings). The distribution of trees and topographic variation make it challenging to monitor the snowpack with in-situ observations. Airborne LiDAR has improved our ability to monitor snowpack over large areas in montane and forested environments because of its high sampling rate and ability to penetrate the canopy. However, these LiDAR flights can be too expensive and time-consuming to process, making it hard to use them for real-time snow monitoring. In this research, we evaluate Structure from Motion (SfM) as an alternative to Airborne LiDAR to generate high-resolution snow depth data in forested environments. This past winter, we conducted a snow field campaign over Arizona's Mogollon Rim where we acquired aerial LiDAR, multi-angle aerial photography from a UAV, and extensive field observations of snow depth at two sites. LiDAR and SFM derived snow depth maps were generated by comparing "snow-on" and "snow-off" LiDAR and SfM data. The SfM- and LiDAR-generated snow depth maps were similar at a site with fewer trees, though there were more discrepancies at a site with more trees. Both compared reasonably well with the field observations at the sparser forested site, with poorer agreement at the denser forested site. Finally, although the SfM produced point clouds with much higher point densities than the aerial LiDAR, the SfM was not able to produce meaningful snow depth estimates directly underneath trees and had trouble in areas with deep shadows. Based on these findings, we are optimizing our UAV data acquisition strategies for this upcoming field season. We are using these data, along with high-resolution hydrological modeling, to gain a better understanding of how

Short Communication. Comparing flammability traits among fire-stricken (low elevation) and non fire-stricken (high elevation) conifer forest species of Europe: A test of the Mutch hypothesis

OpenAIRE

A. P. Dimitrakopoulos; I. D. Mitsopoulos; A. Kaliva

2013-01-01

Aim of study. The flammability of the main coniferous forest species of Europe, divided into two groups according to their fire regime and altitudinal distribution, was tested in an effort to detect species-specific differences that may have an influence on community-wide fire regimes.Area of study. Conifer species comprising low- and high-elevation forests in Europe.Materials and Methods. The following conifer species were tested: low elevation; Pinus halepensis (Aleppo pine), Pinus brutia (...

The fossil Osmundales (Royal Ferns)—a phylogenetic network analysis, revised taxonomy, and evolutionary classification of anatomically preserved trunks and rhizomes

OpenAIRE

Benjamin Bomfleur; Guido W. Grimm; Stephen McLoughlin

2017-01-01

The Osmundales (Royal Fern order) originated in the late Paleozoic and is the most ancient surviving lineage of leptosporangiate ferns. In contrast to its low diversity today (less than 20 species in six genera), it has the richest fossil record of any extant group of ferns. The structurally preserved trunks and rhizomes alone are referable to more than 100 fossil species that are classified in up to 20 genera, four subfamilies, and two families. This diverse fossil record constitutes an exce...

Genome size evolution in Ontario ferns (Polypodiidae): evolutionary correlations with cell size, spore size, and habitat type and an absence of genome downsizing.

Science.gov (United States)

Henry, Thomas A; Bainard, Jillian D; Newmaster, Steven G

2014-10-01

Genome size is known to correlate with a number of traits in angiosperms, but less is known about the phenotypic correlates of genome size in ferns. We explored genome size variation in relation to a suite of morphological and ecological traits in ferns. Thirty-six fern taxa were collected from wild populations in Ontario, Canada. 2C DNA content was measured using flow cytometry. We tested for genome downsizing following polyploidy using a phylogenetic comparative analysis to explore the correlation between 1Cx DNA content and ploidy. There was no compelling evidence for the occurrence of widespread genome downsizing during the evolution of Ontario ferns. The relationship between genome size and 11 morphological and ecological traits was explored using a phylogenetic principal component regression analysis. Genome size was found to be significantly associated with cell size, spore size, spore type, and habitat type. These results are timely as past and recent studies have found conflicting support for the association between ploidy/genome size and spore size in fern polyploid complexes; this study represents the first comparative analysis of the trend across a broad taxonomic group of ferns.

New fern records for Kilimanjaro | Hemp | Journal of East African ...

African Journals Online (AJOL)

Working on the flora and vegetation of Mt Kilimanjaro, Tanzania, 17 ferns in 10 families were found that had not yet been recorded for the floral region T2. The altitudinal range, localities and habitat description are given for Adiantum raddianum, Asplenium bugoiense, Blechnum ivohibense, Blotiella stipitata, Dryopteris ...

The physiological resilience of fern sporophytes and gametophytes: advances in water relations offer new insights into an old lineage

Directory of Open Access Journals (Sweden)

Jarmila ePittermann

2013-08-01

Full Text Available Ferns are some of the oldest vascular plants in existence and they are the second most diverse lineage of tracheophytes next to angiosperms. Recent efforts to understand fern success have fo-cused on the physiological capacity and stress tolerance of both the sporophyte and the gameto-phyte generations. In this review, we examine these insights through the lens of plant water rela-tions, focusing primarily on the form and function of xylem tissue in the sporophyte, as well as the tolerance to and recovery from drought and desiccation stress in both stages of the fern life cycle. The absence of secondary xylem in ferns is compensated by selection for efficient primary xylem composed of large, closely arranged tracheids with permeable pit membranes. Protection from drought-induced hydraulic failure appears to arise from a combination of pit membrane traits and the arrangement of vascular bundles. Features such as tracheid-based xylem and vari-ously sized megaphylls are shared between ferns and more derived lineages, and offer an oppor-tunity to compare convergent and divergent hydraulic strategies critical to the success of xylem-bearing plants. Fern gametophytes show a high degree of desiccation tolerance but new evidence shows that morphological attributes in the gametophytes may facilitate water retention, though little work has addressed the ecological significance of this variation. We conclude with an emergent hypothesis that selection acted on the physiology of both the sporophyte and gameto-phyte generations in a synchronous manner that is consistent with selection for drought tolerance in the epiphytic niche, and the increasingly diverse habitats of the mid to late Cenozoic.

Size-resolved fluxes of sub-100-nm particles over forests

DEFF Research Database (Denmark)

Pryor, Sara; Barthelmie, Rebecca Jane; Spaulding, A.M.

2009-01-01

Dry deposition of atmospheric particles is critically dependent on particle size and plays a key role in dictating the mass and number distributions of atmospheric particles. However, modeling dry deposition is constrained by a lack of understanding of controlling dependencies and accurate size......-resolved observations. We present size-resolved particle number fluxes for sub-100-nm particle diameters (Dp) over a deciduous forest derived using eddy covariance applied to data from a fast mobility particle sizer. The size-resolved particle number fluxes in 18 diameters between 8 and 100 nm were collected during...... leaf-on and are statistically robust. Particle deposition velocities normalized by friction velocity (v d +) are approximately four times smaller than comparable values for coniferous forests reported elsewhere. Comparison of the data with output from a new one-dimensional mechanistic particle...

Microbial activities in forest soils exposed to chronic depositions from a lignite power plant

Energy Technology Data Exchange (ETDEWEB)

Klose, S.; Wernecke, K.D.; Makeschin, F. [Technical University of Dresden, Tharandt (Germany)

2004-12-01

Atmospheric emissions of fly ash and SO{sub 2} from lignite-fired power plants strongly affect large forest areas in Germany. The impact of different deposition loads on the microbial biomass and enzyme activities was studied at three forest sites (Picea abies (L.) Karst.) along an emission gradient of 3, 6, and 15 km downwind of a coal-fired power plant, representing high, moderate and low emission rates. An additional site at a distance of 3 km from the power plant was chosen to study the influence of forest type on microbial parameters in coniferous forest soils under fly ash and SO{sub 2} emissions. Soil microbial biomass C and N, CO{sub 2} evolved and activities of L-asparaginase, L-glutaminase, beta-glucosidase, acid phosphatase and arylsulfatase (expressed on dry soil and organic C basis) were determined in the forest floor (L, Of and Oh horizon) and mineral top soil (0-10 cm). It is concluded that chronic fly ash depositions decrease litter decomposition by influencing specific microbial and enzymatic processes in forest soils.

Minimizing measurement uncertainties of coniferous needle-leaf optical properties, part I: methodological review

NARCIS (Netherlands)

Yanez Rausell, L.; Schaepman, M.E.; Clevers, J.G.P.W.; Malenovsky, Z.

2014-01-01

Optical properties (OPs) of non-flat narrow plant leaves, i.e., coniferous needles, are extensively used by the remote sensing community, in particular for calibration and validation of radiative transfer models at leaf and canopy level. Optical measurements of such small living elements are,

Interspecific variation in growth responses to tree size, competition and climate of western Canadian boreal mixed forests.

Science.gov (United States)

Jiang, Xinyu; Huang, Jian-Guo; Cheng, Jiong; Dawson, Andria; Stadt, Kenneth J; Comeau, Philip G; Chen, Han Y H

2018-08-01

Tree growth of boreal forest plays an important role on global carbon (C) cycle, while tree growth in the western Canadian boreal mixed forests has been predicted to be negatively affected by regional drought. Individual tree growth can be controlled by many factors, such as competition, climate, tree size and age. However, information about contributions of different factors to tree growth is still limited in this region. In order to address this uncertainty, tree rings of two dominant tree species, trembling aspen (Populus tremuloides Michx.) and white spruce (Picea glauca (Moench.) Voss), were sampled from boreal mixed forest stands distributed across Alberta, Canada. Tree growth rates over different time intervals (10years interval, 1998-2007; 20years interval, 1988-2007; 30years interval, 1978-2007) were calculated to study the effects of different factors (tree size, competition, climate, and age) on tree growth. Results indicated that tree growth of two species were both primarily affected by competition or tree size, while climatic indices showed less effects on tree growth. Growth of trembling aspen was significantly affected by inter- and intraspecific competition, while growth of white spruce was primarily influenced by tree size, followed by competition. Positive relationship was found between growth of white spruce and competition index of coniferous group, suggesting an intraspecific mutualism mechanism within coniferous group. Our results further suggested that competition driven succession was the primary process of forest composition shift in the western Canadian boreal mixed forest. Although drought stress increased tree mortality, decline of stem density under climate change released competition stress of surviving trees, which in turn sustained growth of surviving trees. Therefore, climatic indices showed fewer effects on growth of dominant tree species compared to other factors in our study. Copyright © 2018 Elsevier B.V. All rights reserved.

The accumulation and subcellular distribution of arsenic and antimony in four fern plants.

Science.gov (United States)

Feng, R; Wang, X; Wei, C; Tu, S

2015-01-01

In the present study, Pteris cretica 'Albo-Lineata' (PC), Pteris fauriei (PF), Humata tyermanii Moore (HT), and Pteris ensiformis Burm (PE), were selected to explore additional plant materials for the phytoremediation of As and Sb co-contamination. To some extent, the addition of As and Sb enhanced the growth of HT, PE, and PF. Conversely, the addition of As and Sb negatively affected the growth of PC and was accompanied with the accumulation of high levels of As and Sb in the roots. The highest concentration of Sb was recorded as 6405 mg kg(-1) in the roots of PC, and that for As was 337 mg kg(-1) in the rhizome of PF. To some degree, As and Sb stimulated the uptake of each other in these ferns. Arsenic was mainly stored in the cytoplasmic supernatant (CS) fraction, followed by the cell wall (CW) fraction. In contrast, Sb was mainly found in the CW fraction and, to a lesser extent, in the CS fraction, suggesting that the cell wall and cytosol play different roles in As and Sb accumulation by fern plants. This study demonstrated that these fern plants show a good application potential in the phytoremediation of As and Sb co-contaminated environments.

Evaluating the Community Land Model (CLM4.5) at a coniferous forest site in northwestern United States using flux and carbon-isotope measurements

Science.gov (United States)

Duarte, Henrique F.; Raczka, Brett M.; Ricciuto, Daniel M.; Lin, John C.; Koven, Charles D.; Thornton, Peter E.; Bowling, David R.; Lai, Chun-Ta; Bible, Kenneth J.; Ehleringer, James R.

2017-09-01

Droughts in the western United States are expected to intensify with climate change. Thus, an adequate representation of ecosystem response to water stress in land models is critical for predicting carbon dynamics. The goal of this study was to evaluate the performance of the Community Land Model (CLM) version 4.5 against observations at an old-growth coniferous forest site in the Pacific Northwest region of the United States (Wind River AmeriFlux site), characterized by a Mediterranean climate that subjects trees to water stress each summer. CLM was driven by site-observed meteorology and calibrated primarily using parameter values observed at the site or at similar stands in the region. Key model adjustments included parameters controlling specific leaf area and stomatal conductance. Default values of these parameters led to significant underestimation of gross primary production, overestimation of evapotranspiration, and consequently overestimation of photosynthetic 13C discrimination, reflected in reduced 13C : 12C ratios of carbon fluxes and pools. Adjustments in soil hydraulic parameters within CLM were also critical, preventing significant underestimation of soil water content and unrealistic soil moisture stress during summer. After calibration, CLM was able to simulate energy and carbon fluxes, leaf area index, biomass stocks, and carbon isotope ratios of carbon fluxes and pools in reasonable agreement with site observations. Overall, the calibrated CLM was able to simulate the observed response of canopy conductance to atmospheric vapor pressure deficit (VPD) and soil water content, reasonably capturing the impact of water stress on ecosystem functioning. Both simulations and observations indicate that stomatal response from water stress at Wind River was primarily driven by VPD and not soil moisture. The calibration of the Ball-Berry stomatal conductance slope (mbb) at Wind River aligned with findings from recent CLM experiments at sites characterized by

Evaluating the Community Land Model (CLM4.5 at a coniferous forest site in northwestern United States using flux and carbon-isotope measurements

Directory of Open Access Journals (Sweden)

H. F. Duarte

2017-09-01

Full Text Available Droughts in the western United States are expected to intensify with climate change. Thus, an adequate representation of ecosystem response to water stress in land models is critical for predicting carbon dynamics. The goal of this study was to evaluate the performance of the Community Land Model (CLM version 4.5 against observations at an old-growth coniferous forest site in the Pacific Northwest region of the United States (Wind River AmeriFlux site, characterized by a Mediterranean climate that subjects trees to water stress each summer. CLM was driven by site-observed meteorology and calibrated primarily using parameter values observed at the site or at similar stands in the region. Key model adjustments included parameters controlling specific leaf area and stomatal conductance. Default values of these parameters led to significant underestimation of gross primary production, overestimation of evapotranspiration, and consequently overestimation of photosynthetic 13C discrimination, reflected in reduced 13C : 12C ratios of carbon fluxes and pools. Adjustments in soil hydraulic parameters within CLM were also critical, preventing significant underestimation of soil water content and unrealistic soil moisture stress during summer. After calibration, CLM was able to simulate energy and carbon fluxes, leaf area index, biomass stocks, and carbon isotope ratios of carbon fluxes and pools in reasonable agreement with site observations. Overall, the calibrated CLM was able to simulate the observed response of canopy conductance to atmospheric vapor pressure deficit (VPD and soil water content, reasonably capturing the impact of water stress on ecosystem functioning. Both simulations and observations indicate that stomatal response from water stress at Wind River was primarily driven by VPD and not soil moisture. The calibration of the Ball–Berry stomatal conductance slope (mbb at Wind River aligned with findings from recent CLM experiments at

Response of nitrogen-fixing water fern Azolla biofertilization to rice crop.

Science.gov (United States)

Bhuvaneshwari, K; Singh, Pawan Kumar

2015-08-01

The water fern Azolla harbors nitrogen-fixing cyanobacterium Anabaena azollae as symbiont in its dorsal leaves and is known as potent N 2 fixer. Present investigation was carried out to study the influence of fresh Azolla when used as basal incorporation in soil and as dual cropped with rice variety Mahsoori separately and together with and without chemical nitrogen fertilizer in pots kept under net house conditions. Results showed that use of Azolla as basal or dual or basal plus dual influenced the rice crop positively where use of fern as basal plus dual was superior and served the nitrogen requirement of rice. There was marked increase in plant height, number of effective tillers, dry mass and nitrogen content of rice plants with the use of Azolla and N-fertilizers alone and other combinations. The use of Azolla also increased organic matter and potassium contents of the soil.

Interpreting the deposition and vertical migration characteristics of 137Cs in forest soil after the Fukushima Dai-ichi Nuclear Power Plant accident.

Science.gov (United States)

Kang, Seongjoo; Yoneda, Minoru; Shimada, Yoko; Satta, Naoya; Fujita, Yasutaka; Shin, In Hwan

2017-08-01

We investigated the deposition and depth distributions of radiocesium in the Takizawa Research Forest, Iwate Prefecture, in order to understand the behavior of radionuclides released from the Fukushima Dai-ichi Nuclear Power Plant. The deposition distribution and vertical depth distribution of radiocesium in the soil were compared between topographically distinct parts of the forest where two different tree species grow. The results for all investigated locations show that almost 85% of the radiocesium has accumulated in the region of soil from the topmost organic layer to a soil depth of 0-4 cm. However, no activity was detected at depths greater than 20 cm. Analysis of the radiocesium deposition patterns in forest locations dominated by either coniferous or deciduous tree species suggests that radiocesium was sequestered and retained in higher concentrations in coniferous areas. The deposition data showed large spatial variability, reflecting the differences in tree species and topography. The variations in the measured 137 Cs concentrations reflected the variability in the characteristics of the forest floor environment and the heterogeneity of the initial ground-deposition of the Fukushima fallout. Sequential extraction experiments showed that most of the 137 Cs was present in an un-exchangeable form with weak mobility. Nevertheless, the post-vertical distribution of 137 Cs is expected to be governed by the percentage of exchangeable 137 Cs in the organic layer and the organic-rich upper soil horizons.

Three new fern records for Kilimanjaro | Hemp | Journal of East ...

African Journals Online (AJOL)

Working on the flora and vegetation of Mt. Kilimanjaro, Tanzania, three ferns in three families were found that are not yet recorded for the floral region T2. The altitudinal range, localities and habitat description are given for Adiantum reniforme, Azolla africana and Trichomanes radicans. Journal of East African Natural History ...

The Enrichment and Transfer of Heavy Metals for Two Ferns in Pb-Zn Tailing

Directory of Open Access Journals (Sweden)

Mai Jiajie

2017-01-01

Full Text Available The enrichment and transfer of 8 heavy metals of Equisetum ramosissimum and Pteris vittata growing naturally close to edge of the sewage pool in Bencun Pb-Zn Tailing, Eastern Guangdong were investigated. The results indicated that the pollution of Cd, Pb, Hg, Zn was very severe in this tailing, followed by Cu and Mn. The potential ecological risk of heavy metals was assessed to be very strong based on soil background values of Guangdong Province and at high risk according to criteria of the second grade State Soil Environmental Quality Standard, and Cd, Hg, Pb were the main factors leading to potential ecological risk. The content of 8 heavy metals in the two ferns did not reach critical content of hyperaccumulator, so neither of them was typical hyperaccumulator, but both had a certain tolerance to these heavy metal pollution. Underground parts of Pteris vittata had an enrichment coefficient above 1 and that of Equisetum ramosissimum had a value near 1, therefore the two ferns could be utilized as potential enrichment plants. The two ferns have strong adaptability to the tailing habitat and can be used as pioneers in ecological restoration of Pb-Zn tailings.

[Simulating the effects of climate change and fire disturbance on aboveground biomass of boreal forests in the Great Xing'an Mountains, Northeast China].

Science.gov (United States)

Luo, Xu; Wang, Yu Li; Zhang, Jin Quan

2018-03-01

Predicting the effects of climate warming and fire disturbance on forest aboveground biomass is a central task of studies in terrestrial ecosystem carbon cycle. The alteration of temperature, precipitation, and disturbance regimes induced by climate warming will affect the carbon dynamics of forest ecosystem. Boreal forest is an important forest type in China, the responses of which to climate warming and fire disturbance are increasingly obvious. In this study, we used a forest landscape model LANDIS PRO to simulate the effects of climate change on aboveground biomass of boreal forests in the Great Xing'an Mountains, and compared direct effects of climate warming and the effects of climate warming-induced fires on forest aboveground biomass. The results showed that the aboveground biomass in this area increased under climate warming scenarios and fire disturbance scenarios with increased intensity. Under the current climate and fire regime scenario, the aboveground biomass in this area was (97.14±5.78) t·hm -2 , and the value would increase up to (97.93±5.83) t·hm -2 under the B1F2 scenario. Under the A2F3 scenario, aboveground biomass at landscape scale was relatively higher at the simulated periods of year 100-150 and year 150-200, and the value were (100.02±3.76) t·hm -2 and (110.56±4.08) t·hm -2 , respectively. Compared to the current fire regime scenario, the predicted biomass at landscape scale was increased by (0.56±1.45) t·hm -2 under the CF2 scenario (fire intensity increased by 30%) at some simulated periods, and the aboveground biomass was reduced by (7.39±1.79) t·hm -2 in CF3 scenario (fire intensity increased by 230%) at the entire simulation period. There were significantly different responses between coniferous and broadleaved species under future climate warming scenarios, in that the simulated biomass for both Larix gmelinii and Betula platyphylla showed decreasing trend with climate change, whereas the simulated biomass for Pinus

Arthropods and passerine birds in coniferous forest. The impact of acidification and needle-loss

Energy Technology Data Exchange (ETDEWEB)

Gunnarsson, B. [Goeteborg Univ., Dept. of Zoology, Sect. of Animal Ecology, Goeteborg (Sweden)

1995-12-31

The micro-habitat structure on coniferous trees changes as a result of needle-loss. This structural change in the vegetation may affect arthropods living in spruce Picea abies by indirect mechanisms, e.g. altered relations between prey and predators. The impact of acidification and needle-loss on some tree-living arthropods and passerine birds is reviewed. New information about the taxonomic composition of spiders in relation to needle density in a field experiments is reported. The main combined findings from the review and field experiments are: 1) Acid precipitation may be toxic because of high H{sup +} concentrations. However, simulated acid rain (pH 4.0) did not reduce the growth rate of a spruce-living spider. There is a present no evidence of toxic effect on arthropods at this level of pH. 2) Experiments in the field and laboratory and data from natural populations suggested that spruce-living arthropods are affected by the needle density of branches. These data showed a positive correlation between needle density and spider abundance. However, a large-scale field experiment could not confirm this relationship. 3) The interaction between bird predation and needle density was examined in a large-scale field experiment. There were strong negative effects of bird predation on arthropod abundance. Moreover, the taxonomic composition among spiders changed as a result of bird predation: raptorial spiders increased their relative abundance whereas sheetweb spiders decreased their relative abundance when bird predation was excluded. There were also some cases of bird predation/needle density interactions. In the absence of bird predation, the needle density affected the spider size distribution: large spiders were more common on needle-sparse branches than on needle-dens ones. The species composition was affected by similar interactions, e.g. bird predation effects on crab spiders (Thomisidae) were found on needle-sparse branches only. (Abstract Truncated)

Phyto-toxicity and Phyto-remediation Potential of Mercury in Indian Mustard and Two Ferns with Mercury Contaminated Water and Oak Ridge Soil

International Nuclear Information System (INIS)

Su, Y.; Han, F.X.; Chen, J.; Shiyab, S.; Monts, D.L.; Monts, D.L.

2009-01-01

Phyto-remediation is an emerging technology that uses various plants to degrade, extract, contain, or immobilize contaminants from soil and water. Certain fern and Indian mustard species have been suggested as candidates for phyto-remediation of heavy metal-contaminated soil and water because of their high efficiency of accumulating metals in shoots and their high biomass production. Currently, no known hyper-accumulator plants for mercury have been found. Here we report the Hg uptake and phyto-toxicity by two varieties of fern and Indian mustard. Their potential for Hg phyto-remediation application was also investigated. Anatomical, histochemical and biochemical approaches were used to study mercury phyto-toxicity as well as anti-oxidative responses in ferns [Chinese brake fern (P. vittata) and Boston fern (N. exaltata)] and Indian mustard (Florida broadleaf and longstanding) (Brassica juncea L.) grown in a hydroponic system. Phyto-remediation potentials of these plant species were estimated based on their Hg uptake performance with contaminated soils from Oak Ridge (TN, USA). Our results show that mercury exposure led to severe phyto-toxicity accompanied by lipid peroxidation and rapid accumulation of hydrogen peroxide (H 2 O 2 ) in P. vittata, but not in N. exaltata. The two cultivars of fern responded differently to mercury exposure in terms of anti-oxidative enzymes (superoxide dismutase, SOD; catalase, CAT; peroxidase, POD; glutathione reductase, GR). Mercury exposure resulted in the accumulation of ascorbic acid (ASA) and glutathione (GSH) in the shoots of both cultivars of fern. On the other hand, Indian mustard effectively generated an enzymatic antioxidant defense system (especially CAT) to scavenge H 2 O 2 , resulting in lower H 2 O 2 in shoots with higher mercury concentrations. These two cultivars of Indian mustard demonstrated an efficient metabolic defense and adaptation system to mercury-induced oxidative stress. In both varieties of fern and Indian

Determination of heavy metals in soil and different parts of Diplazium esculentum (medicinal fern)

Science.gov (United States)

Jasim, Hind S.; Idris, Mushrifah; Abdullah, Aminah; Kadhum, A. A. H.

2014-09-01

Diplazium esculentum is a widely used medicinal fern in Malaysia and other regions worldwide. Heavy metals in plants should be determined because prolonged human intake of toxic trace elements, even at low doses, results in organ malfunction and causes chronic toxicity. Hence, substantial information should be obtained from plants that grow on soils containing high concentrations of heavy metals. This study aimed to determine the physicochemical characteristics of soil and heavy metal concentrations (Pb, Cr, Mn, Cu, and Zn) in different parts of D. esculentum and soil, which were collected from the fern garden of Universiti Kebangsaan Malaysia. Results showed that heavy metals were highly accumulated in D. esculentum roots.

Inventory of species and cultivars potentially valuable for forest/biomass production

Energy Technology Data Exchange (ETDEWEB)

Lavoie, G

1981-01-01

To prepare a guide for experiments in mini-rotation or short rotation forest production, potentially valuable species and cultivars have been inventoried. In this text, 288 species are listed under 31 genera, 27 deciduous and 4 coniferous. This partial inventory was made for the Northern Hemisphere and different climates, ranging from the tropical zone to the cold temperate zone. To be included a species had to satisfy the following conditions: ease of established and rapid juvenile growth. The list of species and cultivars is given in alphabetical order. 55 references.

The scaly tree ferns (Cyatheaceae-Polypodiopsida) of Brazil

OpenAIRE

Weigand, Anna; Lehnert, Marcus

2016-01-01

ABSTRACT A synopsis of all scaly tree fern species (Cyatheaceae) occurring in Brazil is presented. We recognize 51 species in three genera [Sphaeropteris one species, Alsophila four species (one subspecies, two varieties), and Cyathea 45 species (one variety) ] with 17 taxa being endemic to Brazil. One hybrid endemic to Brazil is recognized. Further included are five species that have not yet been recorded in Brazil, but are expected here because they are found in adjacent countries and occur...

Insect-induced tree mortality of boreal forests in eastern Canada under a changing climate.

Science.gov (United States)

Zhang, Xiongqing; Lei, Yuancai; Ma, Zhihai; Kneeshaw, Dan; Peng, Changhui

2014-06-01

Forest insects are major disturbances that induce tree mortality in eastern coniferous (or fir-spruce) forests in eastern North America. The spruce budworm (SBW) (Choristoneura fumiferana [Clemens]) is the most devastating insect causing tree mortality. However, the relative importance of insect-caused mortality versus tree mortality caused by other agents and how this relationship will change with climate change is not known. Based on permanent sample plots across eastern Canada, we combined a logistic model with a negative model to estimate tree mortality. The results showed that tree mortality increased mainly due to forest insects. The mean difference in annual tree mortality between plots disturbed by insects and those without insect disturbance was 0.0680 per year (P eastern Canada but that tree mortality induced by insect outbreaks will decrease in eastern Canada under warming climate.

Tear ferning in normal dogs and dogs with keratoconjunctivitis sicca ...

African Journals Online (AJOL)

This study evaluates tear ferning as an ancillary technique for the evaluation of the canine tear film in normal eyes and eyes affected by keratoconjunctivitis sicca (KCS). Thirty dogs with KCS and 50 control dogs with normal tear film were evaluated with a full ophthalmoscopic examination and a Schirmer tear test type 1 ...

Western sword fern avoids the extreme drought of 2012-2014

Science.gov (United States)

Emily E. Burns; Peter Cowan; Wendy Baxter; Deborah Zierten; Jarmilla Pittermann

2017-01-01

The California drought of 2012 to 2014 was the most severe drought on record for the last century and likely millennium. Warm temperatures with below-average precipitation compounded over the three-year period, creating significant and sustained aridity over the course of three growing seasons throughout the coast redwood ecosystem. The citizen science project, Fern...

Do ferns and lycophytes function as medicinal plants? A study of their low representation in traditional pharmacopoeias.

Science.gov (United States)

Reinaldo, Rafael Corrêa Prota dos Santos; Santiago, Augusto César Pessôa; Medeiros, Patrícia Muniz; Albuquerque, Ulysses Paulino

2015-12-04

Ethnobotany is becoming an important tool for understanding how traditional medical systems are organized and which variables affect their structure and dynamics. However, some phenomena observed in ethnobotanical studies led us to question whether such phenomena are real or methodological artifacts. The small proportion of ferns and lycophytes in ethnobotanical surveys of medicinal plants is one such phenomenon, and its causes should be identified using different approach levels. The present study aimed to clarify the reasons for a low representation of these two groups in studies of medicinal plants. The present study considered the following hypotheses: 1) ferns and lycophytes are little represented in different ethnobotanical studies because of inadequate data collection methods to record these species; 2) ferns and lycophytes are little represented because of the local perception of their low therapeutic efficacy; and 3) species of ferns and lycophytes are represented in local pharmacopoeias in proportion to the size of their families. We chose rural communities from Chapada do Araripe, Northeast Brazil to test our hypotheses. Data on the medicinal plant repertoires of the communities and on the perceived therapeutic efficacy of ferns were obtained using two different methods, semi-structured interviews associated with free lists and a checklist interview, both applied to local specialists. The resulting data were analyzed differently for each test. In addition, data regarding the total flora x medicinal flora ratio were obtained with a floristic survey and accessing data banks from previous studies performed by our research team. All hypotheses were confirmed, showing that all three factors contributed to the low representation of these plant groups as medicinal resources. The present study showed that free-list interviews are not a good method to access traditional knowledge of medicinal ferns and lycophytes and that the use of visual stimuli can help the

Sales of wood from state forests in 2010

International Nuclear Information System (INIS)

Office National des Forets

2011-01-01

After two years of diminishing demand in both volume and prices, all products experienced a recovery in 2010 that was significant for coniferous workable timber and for industrial timber but less so for deciduous workable timber particularly beech. Taking all species together, the supply of timber increased 10%, volumes sold went up 19% while the average unit price grew 12%. As a result, the overall turnover for French state-owned forests went up by 34%. Concerning the marketing channels for timber, supply contract volumes increased by 250,000 m 3 and accounted for 18% of overall volumes sold; their prices followed the general trends observed on the market. (authors)

Host range and genetic relatedness of Colletotrichum acutatum isolates from fruit crops and leatherleaf fern in Florida.

Science.gov (United States)

MacKenzie, S J; Peres, N A; Barquero, M P; Arauz, L F; Timmer, L W

2009-05-01

Isolates of Colletotrichum acutatum were collected from anthracnose-affected strawberry, leatherleaf fern, and Key lime; ripe-rot-affected blueberry; and postbloom fruit drop (PFD)-affected sweet orange in Florida. Additional isolates from ripe-rot-affected blueberry were collected from Georgia and North Carolina and from anthracnose-affected leatherleaf fern in Costa Rica. Pathogenicity tests on blueberry and strawberry fruit; foliage of Key lime, leatherleaf fern, and strawberry; and citrus flowers showed that isolates were highly pathogenic to their host of origin. Isolates were not pathogenic on foliage of heterologous hosts; however, several nonhomologous isolates were mildly or moderately pathogenic to citrus flowers and blueberry isolates were pathogenic to strawberry fruit. Based on sequence data from the internal transcribed spacer (ITS)1-5.8S rRNA-ITS2 region of the rDNA repeat, the glutaraldehyde-3-phosphate dehydrogenase intron 2 (G3PD), and the glutamine synthase intron 2 (GS), isolates from the same host were identical or very similar to each other and distinct from those isolated from other hosts. Isolates from leatherleaf fern in Florida were the only exception. Among these isolates, there were two distinct G3PD and GS sequences that occurred in three of four possible combinations. Only one of these combinations occurred in Costa Rica. Although maximum parsimony trees constructed from genomic regions individually displayed little or no homoplasy, there was a lack of concordance among genealogies that was consistent with a history of recombination. This lack of concordance was particularly evident within a clade containing PFD, Key lime, and leatherleaf fern isolates. Overall, the data indicated that it is unlikely that a pathogenic strain from one of the hosts examined would move to another of these hosts and produce an epidemic.

Vestigios de Alvar Aalto en la opera prima de Antonio Fernández Alba (1959-62

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Lucía C. Pérez-Moreno

2018-04-01

Full Text Available La obra de Antonio Fernández Alba de los años sesenta ha sido fundamentalmente calificada de orgánica aludiendo a sus consonancias con la arquitectura de Alvar Aalto. Este texto ahonda en la lectura que Fernández Alba presentó sobre la cultura finesa en varios escritos publicados en la revista madrileña Arquitectura, entre los que destaca el ensayo “Valores humanos y estéticos en el diseño finlandés” publicado en 1962. Reflexiones presentadas en este texto tomaron forma en el colegio Nuestra Señora Santa María en Madrid, un proyecto en el que Fernández Alba estaba trabajando en estos mismos años. Sin eludir la condición de colegio católico y femenino del proyecto, se reflexiona en torno a decisiones proyectuales que ponen de manifestó el interés de Fernández Alba por ofrecer a las niñas educadas en sus espacios una arquitectura propicia para el juego, conectada con la naturaleza circundante, no regida por formas preconcebidas, amable en la elección de sus materiales y libre en el uso y disfrute de sus dependencias. En definitiva, una arquitectura que tuvo en cuenta las necesidades psicofísicas de alumnas y profesorado o una arquitectura humanizada, aludiendo al conocido ensayo de Alvar Aalto escrito en 1940.

N : P Stoichiometry in a Forested Runoff during Storm Events: Comparisons with Regions and Vegetation Types

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Lanlan Guo

2012-01-01

Full Text Available Nitrogen and phosphorus are considered the most important limiting elements in terrestrial and aquatic ecosystems. however, very few studies have focused on which is from forested streams, a bridge between these two systems. To fill this gap, we examined the concentrations of dissolved N and P in storm waters from forested watersheds of five regions in Japan, to characterize nutrient limitation and its potential controlling factors. First, dissolved N and P concentrations and the N : P ratio on forested streams were higher during storm events relative to baseflow conditions. Second, significantly higher dissolved inorganic N concentrations were found in storm waters from evergreen coniferous forest streams than those from deciduous broadleaf forest streams in Aichi, Kochi, Mie, Nagano, and with the exception of Tokyo. Finally, almost all the N : P ratios in the storm water were generally higher than 34, implying that the storm water should be P-limited, especially for Tokyo.

N : P stoichiometry in a forested runoff during storm events: comparisons with regions and vegetation types.

Science.gov (United States)

Guo, Lanlan; Chen, Yi; Zhang, Zhao; Fukushima, Takehiko

2012-01-01

Nitrogen and phosphorus are considered the most important limiting elements in terrestrial and aquatic ecosystems. however, very few studies have focused on which is from forested streams, a bridge between these two systems. To fill this gap, we examined the concentrations of dissolved N and P in storm waters from forested watersheds of five regions in Japan, to characterize nutrient limitation and its potential controlling factors. First, dissolved N and P concentrations and the N : P ratio on forested streams were higher during storm events relative to baseflow conditions. Second, significantly higher dissolved inorganic N concentrations were found in storm waters from evergreen coniferous forest streams than those from deciduous broadleaf forest streams in Aichi, Kochi, Mie, Nagano, and with the exception of Tokyo. Finally, almost all the N : P ratios in the storm water were generally higher than 34, implying that the storm water should be P-limited, especially for Tokyo.

Assessing Ecosystem Drought Response in CLM 4.5 Using Site-Level Flux and Carbon-Isotope Measurements: Results From a Pacific Northwest Coniferous Forest

Science.gov (United States)

Duarte, H.; Raczka, B. M.; Koven, C. D.; Ricciuto, D. M.; Lin, J. C.; Bowling, D. R.; Ehleringer, J. R.

2015-12-01

The frequency, extent, and severity of droughts are expected to increase in the western United States as climate changes occur. The combination of warmer temperature, larger vapor pressure deficit, reduced snowfall and snow pack, earlier snow melt, and extended growing seasons is expected to lead to an intensification of summer droughts, with a direct impact on ecosystem productivity and therefore on the carbon budget of the region. In this scenario, an accurate representation of ecosystem drought response in land models becomes fundamental, but the task is challenging, especially in regards to stomatal response to drought. In this study we used the most recent release of the Community Land Model (CLM 4.5), which now includes photosynthetic carbon isotope discrimination and revised photosynthesis and hydrology schemes, among an extensive list of updates. We evaluated the model's performance at a coniferous forest site in the Pacific northwest (Wind River AmeriFlux Site), characterized by a climate that has a strong winter precipitation component followed by a summer drought. We ran the model in offline mode (i.e., decoupled from an atmospheric model), forced by observed meteorological data, and used site observations (e.g., surface fluxes, biomass values, and carbon isotope data) to assess the model. Previous field observations indicated a significant negative correlation between soil water content and the carbon isotope ratio of ecosystem respiration (δ13CR), suggesting that δ13CR was closely related to the photosynthetic discrimination against 13CO2 as controlled by stomatal conductance. We used these observations and latent-heat flux measurements to assess the modeled stomatal conductance values and their responses to extended summer drought. We first present the model results, followed by a discussion of potential CLM model improvements in stomatal conductance responses and in the representation of soil water stress (parameter βt) that would more precisely

Water ferns Azolla spp. (Azollaceae as new host plants for the small China-mark moth, Cataclysta lemnata (Linnaeus, 1758 (Lepidoptera, Crambidae, Acentropinae

Directory of Open Access Journals (Sweden)

Atousa Farahpour-Haghani

2017-01-01

Full Text Available Water ferns (Azolla spp., Azollaceae are reported for the first time as host plants for the larvae of the small China-mark moth Cataclysta lemnata (Linnaeus (Lepidoptera: Crambidae: Acentropinae in rice fields and waterways of northern Iran. Cataclysta lemnata is a semi-aquatic species that has been recorded to feed on Lemnaceae and a few other aquatic plants. However, it has not been reported before on Azolla spp. Larvae use water fern as food source and shelter and, at high population density in the laboratory, they completely wiped water fern from the water surface. Feeding was confirmed after rearing more than eight continual generations of C. lemnata on water fern in the laboratory. Adults obtained this way are darker and have darker fuscous markings in both sexes compared with specimens previously reported and the pattern remains unchanged after several generations.

[Litter decomposition and lignocellulose enzyme activities of Actinothuidium hookeri and Cys- topteris montana in alpine timberline ecotone of western Sichuan, China].

Science.gov (United States)

Chen, Ya-mei; He, Run-lian; Deng, Chang-chun; Yang, Wan-qin; Zhang, Jian; Yang, Lin; Liu, Yang

2015-11-01

The mass loss and lignocellulose enzyme activities of Actinothuidium hookeri residues and Cystopteris montana leaf litter in coniferous forest and timberline of western Sichuan, China were investigated. The results showed that both the mass loss rates of A. hookeri and C. Montana in timberline were higher than those in coniferous forest, while enzyme activities in timberline were lower than those in coniferous forest which was contrast with the hypothesis. The mass loss of two ground covers had significant differences in different seasons. The mass loss rate of A. hookeri in snow-covered season accounted for 69.8% and 83.0% of the whole year' s in timberline and coniferous forest, while that of C. montana in the growing season accounted for 82.6% and 83.4% of the whole year' s in timberline and coniferous forest, respectively. C. montana leaf litter decayed faster in the growing season, which was consistent with its higher cellulase activity in the growing season. The result illustrated that the enzymatic hydrolysis of cellulose and hemicellulose might be the main driving force for the early stage of litter decomposition. Multiple linear regression analysis showed that environmental factors and initial litter quality could explain 45.8%-85.1% variation of enzyme activity. The enzyme activities of A. hookeri and C. montana in the process of decomposition were mainly affected by the freeze-thaw cycle in snow-covered season.

How to reconcile wood production and biodiversity conservation? The Pan-European boreal forest history gradient as an "experiment".

Science.gov (United States)

Naumov, Vladimir; Manton, Michael; Elbakidze, Marine; Rendenieks, Zigmars; Priednieks, Janis; Uhlianets, Siarhei; Yamelynets, Taras; Zhivotov, Anton; Angelstam, Per

2018-07-15

There are currently competing demands on Europe's forests and the finite resources and services that they can offer. Forestry intensification that aims at mitigating climate change and biodiversity conservation is one example. Whether or not these two objectives compete can be evaluated by comparative studies of forest landscapes with different histories. We test the hypothesis that indicators of wood production and biodiversity conservation are inversely related in a gradient of long to short forestry intensification histories. Forest management data containing stand age, volume and tree species were used to model the opportunity for wood production and biodiversity conservation in five north European forest regions representing a gradient in landscape history from very long in the West and short in the East. Wood production indicators captured the supply of coniferous wood and total biomass, as well as current accessibility by transport infrastructure. Biodiversity conservation indicators were based on modelling habitat network functionality for focal bird species dependent on different combinations of stand age and tree species composition representing naturally dynamic forests. In each region we randomly sampled 25 individual 100-km 2 areas with contiguous forest cover. Regarding wood production, Sweden's Bergslagen region had the largest areas of coniferous wood, followed by Vitebsk in Belarus and Zemgale in Latvia. NW Russia's case study regions in Pskov and Komi had the lowest values, except for the biomass indicator. The addition of forest accessibility for transportation made the Belarusian and Swedish study region most suitable for wood and biomass production, followed by Latvia and two study regions in NW Russian. Regarding biodiversity conservation, the overall rank among regions was opposite. Mixed and deciduous habitats were functional in Russia, Belarus and Latvia. Old Scots pine and Norway spruce habitats were only functional in Komi. Thus

Soil and water acidification of forest soils in the low-polluted area of Schoenbuch forest reservation

International Nuclear Information System (INIS)

Flegr, M.; Monn, L.

1990-01-01

At a comparatively low atmospheric pollution load of two wood-covered catchment areas the coniferous forest stand is characterized by increased material depositons and large element concentrations in the main root space. This leads to accumulation of acidifying agents and heavy metals in the seepage water. The heavy metals which pass into the recipients with the displaced soil solution determine most of the dispersion of dissolved heavy metals in the plateau landscape. On the other hand, the fraction of heavy metals bound to airborne particulates predominates in the valley landscape because of the stronger relief and the resulting sediment transport. In the shallow groundwaters, the sulfates and nitrate concentrations are much higher than in the deeper ground waters. (orig.) [de

Analyses of soil microbial community compositions and functional genes reveal potential consequences of natural forest succession.

Science.gov (United States)

Cong, Jing; Yang, Yunfeng; Liu, Xueduan; Lu, Hui; Liu, Xiao; Zhou, Jizhong; Li, Diqiang; Yin, Huaqun; Ding, Junjun; Zhang, Yuguang

2015-05-06

The succession of microbial community structure and function is a central ecological topic, as microbes drive the Earth's biogeochemical cycles. To elucidate the response and mechanistic underpinnings of soil microbial community structure and metabolic potential relevant to natural forest succession, we compared soil microbial communities from three adjacent natural forests: a coniferous forest (CF), a mixed broadleaf forest (MBF) and a deciduous broadleaf forest (DBF) on Shennongjia Mountain in central China. In contrary to plant communities, the microbial taxonomic diversity of the DBF was significantly (P the DBF. Furthermore, a network analysis of microbial carbon and nitrogen cycling genes showed the network for the DBF samples was relatively large and tight, revealing strong couplings between microbes. Soil temperature, reflective of climate regimes, was important in shaping microbial communities at both taxonomic and functional gene levels. As a first glimpse of both the taxonomic and functional compositions of soil microbial communities, our results suggest that microbial community structure and function potentials will be altered by future environmental changes, which have implications for forest succession.

Un texto inédito de Wenceslao Fernández Flórez. "¡S.O.S.! ¡Aquí Europa!"

Directory of Open Access Journals (Sweden)

María Teresa BARBADILLO

2009-11-01

Full Text Available Publicamos aquí un texto inédito de Wenceslao Fernández Flórez contenido en 23 cuartillas escritas de su puño y letra, que me fueron confiadas generosamente por sus sobrinos Wenceslao y Antonio Fernández Flórez. El manuscrito no lleva fecha alguna, y el sobre que lo contenía sólo reproduce el título, con la indicación «Charla radiofónica». Don Antonio Fernández Flórez tiene idea de que data de 1934 ó 35, posiblemente del mes de octubre. No obstante, ni en la prensa de esos años, ni en los archivos del Servicio de Documentación escrita de Radio Nacional de España —en donde nos atendieron con suma amabilidad— queda constancia de esta intervención de Fernández Flórez a través de las ondas.

Understory fern community structure, growth and spore production responses to a large-scale hurricane experiment in a Puerto Rico rainforest

Science.gov (United States)

Joanne M. Sharpe; Aaron B. Shiels

2014-01-01

Ferns are abundant in most rainforest understories yet their responses to hurricanes have not been well studied. Fern community structure, growth and spore production were monitored for two years before and five years after a large-scale experiment that simulated two key components of severe hurricane disturbance: canopy openness and debris deposition. The canopy was...

Leaf litter nitrogen concentration as related to climatic factors in Eurasian forests

DEFF Research Database (Denmark)

Liu, Chunjiang; Berg, Bjørn; Kutsch, Werner

2006-01-01

The aim of this study is to determine the patterns of nitrogen (N) concentrations in leaf litter of forest trees as functions of climatic factors, annual average temperature (Temp, °C) and annual precipitation (Precip, dm) and of forest type (coniferous vs. broadleaf, deciduous vs. evergreen, Pinus...... concentration and Temp and Precip by means of regression analysis. Leaf litter data from N2-fixing species were excluded from the analysis. Results: Over the Eurasian continent, leaf litter N concentration increased with increasing Temp and Precip within functional groups such as conifers, broadleaf, deciduous....... In the context of global warming, these regression equations are useful for a better understanding and modelling of the effects of geographical and climatic factors on leaf litter N at a regional and continental scale....

Invariant Hough Random Ferns for Object Detection and Tracking

Directory of Open Access Journals (Sweden)

Yimin Lin

2014-01-01

Full Text Available This paper introduces an invariant Hough random ferns (IHRF incorporating rotation and scale invariance into the local feature description, random ferns classifier training, and Hough voting stages. It is especially suited for object detection under changes in object appearance and scale, partial occlusions, and pose variations. The efficacy of this approach is validated through experiments on a large set of challenging benchmark datasets, and the results demonstrate that the proposed method outperforms state-of-the-art conventional methods such as bounding-box-based and part-based methods. Additionally, we also propose an efficient clustering scheme based on the local patches’ appearance and their geometric relations that can provide pixel-accurate, top-down segmentations from IHRF back-projections. This refined segmentation can be used to improve the quality of online object tracking because it avoids the drifting problem. Thus, an online tracking framework based on IHRF, which is trained and updated in each frame to distinguish and segment the object from the background, is established. Finally, the experimental results on both object segmentation and long-term object tracking show that this method yields accurate and robust tracking performance in a variety of complex scenarios, especially in cases of severe occlusions and nonrigid deformations.

Ants inhabiting myrmecophytic ferns regulate the distribution of lianas on emergent trees in a Bornean tropical rainforest.

Science.gov (United States)

Tanaka, Hiroshi O; Itioka, Takao

2011-10-23

Little is known about the spatial distribution of lianas on emergent trees in tropical rainforests and the factors affecting this distribution. The present study investigated the effects of an arboreal ant species, Crematogaster difformis, which forms myrmecophytic symbioses with two epiphytic ferns, Lecanopteris sp. and Platycerium sp., on the spatial distribution of lianas associated with emergent trees. Living lianas were placed onto trunk surfaces inside and outside the territories of the ants in the canopy, to examine their ability to remove them. The number of leaves pruned by the ants was significantly higher on lianas inside than outside their territories. The spatial overlap of the distributions of lianas and the two ferns on emergent trees were then examined. The frequency of liana colonization of tree crowns was found to be significantly lower on trees with than without ferns. Under the natural conditions, C. difformis workers were observed biting and pruning the lianas. These results suggest that C. difformis regulates the distribution of lianas on emergent trees.

Botanical Survey in Moyo Island, West Nusa Tenggara, Indonesia: Inventory of Flora Collection at Forest

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Trimanto Trimanto

2017-05-01

Full Text Available Nusa Tenggara consists of some small islands, one of them is Moyo Island. The diversity of plant species in this island is not really known for certain. This research was determined to observe the diversity of plant spe-cies in Moyo Island forest. The research was conducted in April 2013 by using floristic analysis method. The characteristic of Moyo Island forest is lowland evergreen rain forest. The results showed there were 60 tree species recorded in Moyo Island forest. There were many fruiting trees and seedling from the trees which show healthy growth, indicated that the plant regeneration in this forest is went well. The diversity of Pteri-dophytes and orchids were not high. Epiphytic fern which often found in the forest were Drynaria quersifolia and Platycerium bifurcatum and terrestrial orchid that dominated in the forest was Nervilia aragoana. Tuber plant was often found in this forest and grew prolifically were Tacca, Dioscorea and Amorphophallus. In coastal area lived a population of Pandanus tectorius. There were three new record plants found. The first was epiphytic orchid: Pteroceras javanica, the second was the epiphytic plant: Hoya verticillata and wild tuber plant: Tacca leontopetaloides.

Observations of distributed snow depth and snow duration within diverse forest structures in a maritime mountain watershed

Science.gov (United States)

Dickerson-Lange, Susan E.; Lutz, James A.; Gersonde, Rolf; Martin, Kael A.; Forsyth, Jenna E.; Lundquist, Jessica D.

2015-11-01

Spatially distributed snow depth and snow duration data were collected over two to four snow seasons during water years 2011-2014 in experimental forest plots within the Cedar River Municipal Watershed, 50 km east of Seattle, Washington, USA. These 40 × 40 m forest plots, situated on the western slope of the Cascade Range, include unthinned second-growth coniferous forests, variable density thinned forests, forest gaps in which a 20 m diameter (approximately equivalent to one tree height) gap was cut in the middle of each plot, and old-growth forest. Together, this publicly available data set includes snow depth and density observations from manual snow surveys, distributed snow duration observations from ground temperature sensors and time-lapse cameras, meteorological data collected at two open locations and three forested locations, and forest canopy data from airborne light detection and ranging (LiDAR) data and hemispherical photographs. These colocated snow, meteorological, and forest data have the potential to improve understanding of forest influences on snow processes, and provide a unique model-testing data set for hydrological analyses in a forested, maritime watershed. We present empirical snow depletion curves within forests to illustrate an application of these data to improve subgrid representation of snow cover in distributed modeling.

Chemotaxonomy for naturally macerated tree-fern cuticles (Medullosales and Marattiales), Carboniferous Sydney and Mabou Sub-Basins, Nova Scotia, Canada

Energy Technology Data Exchange (ETDEWEB)

Zodrow, Erwin L. [Department of Earth Sciences, University College of Cape Breton, PO Box 5300, Nova Scotia, B1P 6L2 Sydney (Canada); Mastalerz, Maria [Indiana Geological Survey, Indiana University, 611 North Walnut Grove, 47405-2208 Bloomington, IN (United States)

2001-07-01

Naturally macerated cuticles (NMC) and one synangium, representing medullosalean and marattialean tree-fern species, from two Carboniferous coalfields in Nova Scotia, Canada, are investigated. The samples were analyzed by infrared spectroscopy (FTIR), and by pyrolysis-gas chromatograph/mass spectrometry (py-Gc/Ms) techniques in search for chemical signatures that would help in developing a chemotaxonomic classification of Carboniferous fern species, assuming genetically dependent make-up of cuticles. FTIR-derived CH{sub 2}/CH{sub 3} ratios, in conjunction with contributions from carboxyl groups, demonstrated a better potential for discriminating between medullosalean genera and species than molecular signatures obtained by py-Gc/Ms. However, the latter provided better data for differentiating medullosalean from marattialean tree ferns as a group. Changes in the chemical make-up of naturally macerated cuticles due to sample preparation are discussed.

MLAOS: A Multi-Point Linear Array of Optical Sensors for Coniferous Foliage Clumping Index Measurement

Directory of Open Access Journals (Sweden)

Yonghua Qu

2014-05-01

Full Text Available The canopy foliage clumping effect is primarily caused by the non-random distribution of canopy foliage. Currently, measurements of clumping index (CI by handheld instruments is typically time- and labor-intensive. We propose a low-cost and low-power automatic measurement system called Multi-point Linear Array of Optical Sensors (MLAOS, which consists of three above-canopy and nine below-canopy optical sensors that capture plant transmittance at different times of the day. Data communication between the MLAOS node is facilitated by using a ZigBee network, and the data are transmitted from the field MLAOS to a remote data server using the Internet. The choice of the electronic element and design of the MLAOS software is aimed at reducing costs and power consumption. A power consumption test showed that, when a 4000 mAH Li-ion battery is used, a maximum of 8–10 months of work can be achieved. A field experiment on a coniferous forest revealed that the CI of MLAOS may reveal a clumping effect that occurs within the canopy. In further work, measurement of the multi-scale clumping effect can be achieved by utilizing a greater number of MLAOS devices to capture the heterogeneity of the plant canopy.

Remote sensing of forest insect disturbances: Current state and future directions.

Science.gov (United States)

Senf, Cornelius; Seidl, Rupert; Hostert, Patrick

2017-08-01

Insect disturbance are important agents of change in forest ecosystems around the globe, yet their spatial and temporal distribution and dynamics are not well understood. Remote sensing has gained much attention in mapping and understanding insect outbreak dynamics. Consequently, we here review the current literature on the remote sensing of insect disturbances. We suggest to group studies into three insect types: bark beetles, broadleaved defoliators, and coniferous defoliators. By so doing, we systematically compare the sensors and methods used for mapping insect disturbances within and across insect types. Results suggest that there are substantial differences between methods used for mapping bark beetles and defoliators, and between methods used for mapping broadleaved and coniferous defoliators. Following from this, we highlight approaches that are particularly suited for each insect type. Finally, we conclude by highlighting future research directions for remote sensing of insect disturbances. In particular, we suggest to: 1) Separate insect disturbances from other agents; 2) Extend the spatial and temporal domain of analysis; 3) Make use of dense time series; 4) Operationalize near-real time monitoring of insect disturbances; 5) Identify insect disturbances in the context of coupled human-natural systems; and 6) Improve reference data for assessing insect disturbances. Since the remote sensing of insect disturbances has gained much interest beyond the remote sensing community recently, the future developments identified here will help integrating remote sensing products into operational forest management. Furthermore, an improved spatiotemporal quantification of insect disturbances will support an inclusion of these processes into regional to global ecosystem models.

The cyanobiont in an Azolla fern is neither Anabaena nor Nostoc.

Science.gov (United States)

Baker, Judith A; Entsch, Barrie; McKay, David B

2003-12-05

The cyanobacterial symbionts in the fern Azolla have generally been ascribed to either the Anabaena or Nostoc genera. By using comparisons of the sequences of the phycocyanin intergenic spacer and a fragment of the 16S rRNA, we found that the cyanobiont from an Azolla belongs to neither of these genera.

Experimental investigation of the processes of dehumidification of coniferous biomass

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Bulba Elena

2017-01-01

Full Text Available This work includes the results of experimental studies of the moisture removal processes in the temperature range from 333 K to 413 K from coniferous woods which are typical for many regions. There are obtained the dependences of the mass rate of moisture removal on time and temperature. The effect of the evaporation of bound moisture was identified for the wood species studied. There are calculated the accommodation coefficient and the partial pressure at the evaporation surface for each type of biomass.

Vertical stratification of soil water storage and release dynamics in Pacific Northwest coniferous forests.

Science.gov (United States)

J.M. Warren; F.C. Meinzer; J.R. Brooks; J.C. Domec

2005-01-01

We characterized vertical variation in the seasonal release of stored soil moisture in old-growth ponderosa pine (OG-PP, xeric), and young and old-growth Douglas-fir (Y-DF, OG-DF, mesic) forests to evaluate changes in water availability for root uptake. Soil water potential (ψ) and volumetric water content (θ...

Two new species of the Phanaeus endymion species group (Coleoptera, Scarabaeidae, Scarabaeinae).

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Moctezuma, Victor; Sánchez-Huerta, José Luis; Halffter, Gonzalo

2017-01-01

Phanaeus bravoensis sp. n. is described from the coniferous-oak forests in the state of Guerrero, and P. huichol sp. n. from coniferous-oak forests and cloud forests in Jalisco and Nayarit. The new species are closely related to P. halffterorum and P. zoque respectively. Morphological trait combination, geographic distribution, and trophic habits show important differences among the studied species. A distribution map and an updated key to separate the species are included.

Field guide to red tree vole nests

Science.gov (United States)

Damon B. Lesmeister; James K. Swingle

2017-01-01

Surveys for red tree vole (Arborimus longicaudus) nests require tree climbing because the species is a highly specialized arboreal rodent that live in the tree canopy of coniferous forests in western Oregon and northwestern California. Tree voles are associated with old coniferous forest (≥80 years old) that are structurally complex, but are often...

Influence of spring phenology on seasonal and annual carbon balance in two contrasting New England forests.

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Richardson, Andrew D; Hollinger, David Y; Dail, D Bryan; Lee, John T; Munger, J William; O'keefe, John

2009-03-01

Spring phenology is thought to exert a major influence on the carbon (C) balance of temperate and boreal ecosystems. We investigated this hypothesis using four spring onset phenological indicators in conjunction with surface-atmosphere CO(2) exchange data from the conifer-dominated Howland Forest and deciduous-dominated Harvard Forest AmeriFlux sites. All phenological measures, including CO(2) source-sink transition dates, could be well predicted on the basis of a simple two-parameter spring warming model, indicating good potential for improving the representation of phenological transitions and their dynamic responsiveness to climate variability in land surface models. The date at which canopy-scale photosynthetic capacity reached a threshold value of 12 micromol m(-2) s(-1) was better correlated with spring and annual flux integrals than were either deciduous or coniferous bud burst dates. For all phenological indicators, earlier spring onset consistently, but not always significantly, resulted in higher gross primary productivity (GPP) and ecosystem respiration (RE) for both seasonal (spring months, April-June) and annual flux integrals. The increase in RE was less than that in GPP; depending on the phenological indicator used, a one-day advance in spring onset increased springtime net ecosystem productivity (NEP) by 2-4 g C m(-2) day(-1). In general, we could not detect significant differences between the two forest types in response to earlier spring, although the response to earlier spring was generally more pronounced for Harvard Forest than for Howland Forest, suggesting that future climate warming may favor deciduous species over coniferous species, at least in this region. The effect of earlier spring tended to be about twice as large when annual rather than springtime flux integrals were considered. This result is suggestive of both immediate and lagged effects of earlier spring onset on ecosystem C cycling, perhaps as a result of accelerated N cycling

Continental scale patterns and predictors of fern richness and phylogenetic diversity

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Nathalie eNagalingum

2015-04-01

Full Text Available Because ferns have a wide range of habitat preferences and are widely distributed, they are an ideal group for understanding how diversity is distributed. Here we examine fern diversity on a broad-scale using standard and corrected richness measures as well as phylogenetic indices; in addition we determine the environmental predictors of each diversity metric. Using the combined records of Australian herbaria, a dataset of over 60,000 records was obtained for 89 genera to infer richness. A phylogenetic tree of all the genera was constructed and combined with the herbarium records to obtain phylogenetic diversity patterns. A hotspot of both taxic and phylogenetic diversity occurs in the Wet Tropics of northeastern Australia. Although considerable diversity is distributed along the eastern coast, some important regions of diversity are identified only after sample-standardization of richness and through the phylogenetic metric. Of all of the metrics, annual precipitation was identified as the most explanatory variable, in part, in agreement with global and regional fern studies. Precipitation was combined with a different variable for each different metric. For corrected richness, precipitation is combined with temperature seasonality, while correlation of phylogenetic diversity to precipitation plus radiation indicates support for the species-energy hypothesis. Significantly high and significantly low phylogenetic diversity were found in geographically separate areas. These areas are correlated with different climatic conditions such as seasonality in precipitation. The use of phylogenetic metrics identifies additional areas of significant diversity, some of which have not been revealed using traditional taxonomic analyses, suggesting that different ecological and evolutionary processes have operated over the continent. Our study demonstrates that it is possible and vital to incorporate evolutionary metrics when inferring biodiversity hotspots

Environmental effect studies on a forest ecosystem in Germany

International Nuclear Information System (INIS)

Yamamoto, Masayoshi; Bunzl, K.

1993-01-01

Long-term acid deposition on a forest ecosystem can have serious impacts on many physicochemical processes in the soil. Since 1984 extensive studies have been carried out in the 'Hoglwald', an old Norway spruce stand near Munich, Germany. In 1986 a variety of radionuclides were deposited in the canopy and on the forest floor of the Hoglwald following the reactor accident at Chernobyl. The amount of 137 Cs from Chernobyl was about 10 times larger than that present in the soil before Chernobyl. Six experimental plots were established in order to study the potential disturbances caused by artificial acid irrigation and compensative liming. Using these fields, investigations on the interception and retention of radionuclides by a coniferous woodland have been done together with the deposition and vertical migration of the radionuclides in the forest. One of the most important results obtained was that 134 Cs deposition velocity in the spruce stand was as high as 5.5 mm/s, and thus higher by a factor of 10 than the corresponding value for the grassland. By evaluating the depth profiles of the Chernobyl-derived 137 Cs in the soil with a compartment model. The fixation of radiocesium in the forest soil was found to be a rather slow process. (author)

Is there foul play in the leaf pocket? The metagenome of floating fern

NARCIS (Netherlands)

Dijkhuizen, L.W.; Brouwer, P.; Bolhuis, H.; Reichart, G.-J.; Koppers, N.; Huettel, B.; Bolger, A.M.; Li, F.-W.; Cheng, S.; Liu, X.; Wong, G.K.-S.; Pryer, K.; Weber, A.; Bräutigam, A.; Schluepmann, H.

2018-01-01

Dinitrogen fixation by Nostoc azollae residing in specialized leaf pockets supports prolific growth of the floating fern Azolla filiculoides. To evaluate contributions by further microorganisms, the A. filiculoides microbiome and nitrogen metabolism in bacteria persistently associated with Azolla

Leaf micromorphology of four medicinal ferns species in Tasik Chini, Pahang

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Nurnida, M. K., E-mail: nurnidakamal@gmail.com; Noraini, T.; Ruzi, A. R.; Idris, S. [School of Environmental and Natural Resource Sciences Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 Bangi, Selangor (Malaysia)

2015-09-25

A leaf micromorphology study was conducted on four selected medicinal ferns species in Tasik Chini, Pahang. The four chosen species were Adiantum latifolium Lam., Lygodium flexuosum (L.) Sw., Lygodium microphyllum (Cav.) R. Br. and Tectaria singaporeana (Wall.) Ching. The objective of this study is to identify the leaf micromorphological characteristics that can be used as supportive scientific data especially in authentification of medicinal ferns species. The procedures involved such as dehydration, critical point drying, gold coated and examination under scanning electron microscope. Results in this study have shown some similarities and variations in the leaf micromorphological characteristics such as presence of cuticular striation, type of epicuticular waxes, structural feature of stomata and also in the presence or absence and type of trichomes. Four types of epicuticular waxes and only one type of trichome were observed, that were specific for some species. As a conclusion, the results of this study definitely proven that leaf micromorphology can be used for species authentification and might useful as preliminary scientific data for future references and further study.

Explotación de peces asociada a la pesquería artesanal de langosta de Juan Fernández (Jasus frontalis

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