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Sample records for rich forest soils

  1. Species richness and soil properties in Pinus ponderosa forests: A structural equation modeling analysis

    Science.gov (United States)

    Laughlin, D.C.; Abella, S.R.; Covington, W.W.; Grace, J.B.

    2007-01-01

    Question: How are the effects of mineral soil properties on understory plant species richness propagated through a network of processes involving the forest overstory, soil organic matter, soil nitrogen, and understory plant abundance? Location: North-central Arizona, USA. Methods: We sampled 75 0.05-ha plots across a broad soil gradient in a Pinus ponderosa (ponderosa pine) forest ecosystem. We evaluated multivariate models of plant species richness using structural equation modeling. Results: Richness was highest at intermediate levels of understory plant cover, suggesting that both colonization success and competitive exclusion can limit richness in this system. We did not detect a reciprocal positive effect of richness on plant cover. Richness was strongly related to soil nitrogen in the model, with evidence for both a direct negative effect and an indirect non-linear relationship mediated through understory plant cover. Soil organic matter appeared to have a positive influence on understory richness that was independent of soil nitrogen. Richness was lowest where the forest overstory was densest, which can be explained through indirect effects on soil organic matter, soil nitrogen and understory cover. Finally, model results suggest a variety of direct and indirect processes whereby mineral soil properties can influence richness. Conclusions: Understory plant species richness and plant cover in P. ponderosa forests appear to be significantly influenced by soil organic matter and nitrogen, which are, in turn, related to overstory density and composition and mineral soil properties. Thus, soil properties can impose direct and indirect constraints on local species diversity in ponderosa pine forests. ?? IAVS; Opulus Press.

  2. Nitrogen and phosphorus resorption in a neotropical rain forest of a nutrient-rich soil.

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    Martínez-Sánchez, José Luis

    2005-01-01

    In tropical forests with nutrient-rich soil tree's nutrient resorption from senesced leaves has not always been observed to be low. Perhaps this lack of consistence is partly owing to the nutrient resorption methods used. The aim of the study was to analyse N and P resorption proficiency from tropical rain forest trees in a nutrient-rich soil. It was hypothesised that trees would exhibit low nutrient resorption in a nutrient-rich soil. The soil concentrations of total N and extractable P, among other physical and chemical characteristics, were analysed in 30 samples in the soil surface (10 cm) of three undisturbed forest plots at 'Estaci6n de Biologia Los Tuxtlas' on the east coast of Mexico (18 degrees 34' - 18 degrees 36' N, 95 degrees 04' - 95 degrees 09' W). N and P resorption proficiency were determined from senescing leaves in 11 dominant tree species. Nitrogen was analysed by microkjeldahl digestion with sulphuric acid and distilled with boric acid, and phosphorus was analysed by digestion with nitric acid and perchloric acid. Soil was rich in total N (0.50%, n = 30) and extractable P (4.11 microg g(-1) n = 30). As expected, trees showed incomplete N (1.13%, n = 11) and P (0.11%, n = 1) resorption. With a more accurate method of nutrient resorption assessment, it is possible to prove that a forest community with a nutrient-rich soil can have low levels of N and P resorption.

  3. Restinga forests of the Brazilian coast: richness and abundance of tree species on different soils.

    Science.gov (United States)

    Magnago, Luiz F S; Martins, Sebastião V; Schaefer, Carlos E G R; Neri, Andreza V

    2012-09-01

    The aim of this study was to determine changes in composition, abundance and richness of species along a forest gradient with varying soils and flood regimes. The forests are located on the left bank of the lower Jucu River, in Jacarenema Natural Municipal Park, Espírito Santo. A survey of shrub/tree species was done in 80 plots, 5x25 m, equally distributed among the forests studied. We included in the sampling all individuals with >3.2 cm diameter at breast height (1.30 m). Soil samples were collected from the surface layer (0-10 cm) in each plot for chemical and physical analysis. The results indicate that a significant pedological gradient occurs, which is influenced by varying seasonal groundwater levels. Restinga forest formations showed significant differences in species richness, except for Non-flooded Forest and Non-flooded Forest Transition. The Canonical Correlation Analysis (CCA) showed that some species are distributed along the gradient under the combined influence of drainage, nutrient concentration and physical characteristics of the soil. Regarding the variables tested, flooding seems to be a more limiting factor for the establishment of plant species in Restinga forests than basic soil fertility attributes.

  4. Forest soils

    Science.gov (United States)

    Charles H. (Hobie) Perry; Michael C. Amacher

    2009-01-01

    Productive soils are the foundation of sustainable forests throughout the United States. Forest soils are generally subjected to fewer disturbances than agricultural soils, particularly those that are tilled, so forest soils tend to have better preserved A-horizons than agricultural soils. Another major contrast between forest and agricultural soils is the addition of...

  5. Substrate availability drives spatial patterns in richness of ammonia-oxidizing bacteria and archaea in temperate forest soils

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    J.S. Norman; J.E. Barrett

    2016-01-01

    We sought to investigate the drivers of richness of ammonia-oxidizing bacteria (AOB) and archaea (AOA) in temperate forest soils. We sampled soils across four experimental watersheds in the Coweeta Hydrologic Laboratory, North Carolina USA. These watersheds are geographically close, but vary in soil chemistry due to differences in land use history. While we...

  6. Nitrogen and phosphorus resorption in a neotropical rain forest of a nutrient-rich soil

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    José Luis Martínez-Sánchez

    2005-09-01

    Full Text Available In tropical forests with nutrient-rich soil tree’s nutrient resorption from senesced leaves has not always been observed to be low. Perhaps this lack of consistence is partly owing to the nutrient resorption methods used. The aim of the study was to analyse N and P resorption proficiency from tropical rain forest trees in a nutrient-rich soil. It was hypothesised that trees would exhibit low nutrient resorption in a nutrient-rich soil. The soil concentrations of total N and extractable P, among other physical and chemical characteristics, were analysed in 30 samples in the soil surface (10 cm of three undisturbed forest plots at ‘Estación de Biología Los Tuxtlas’ on the east coast of Mexico (18°34’ - 18°36’ N, 95°04’ - 95°09’ W. N and P resorption proficiency were determined from senescing leaves in 11 dominant tree species. Nitrogen was analysed by microkjeldahl digestion with sulphuric acid and distilled with boric acid, and phosphorus was analysed by digestion with nitric acid and perchloric acid. Soil was rich in total N (0.50%, n = 30 and extractable P (4.11 µg g-1, n = 30. As expected, trees showed incomplete N (1.13%, n = 11 and P (0.11%, n = 11 resorption. With a more accurate method of nutrient resorption assessment, it is possible to prove that a forest community with a nutrient-rich soil can have low levels of N and P resorption. Rev. Biol. Trop. 53(3-4: 353-359. Epub 2005 Oct 3.En las selvas tropicales con suelos fértiles se ha observado que la reabsorción de nutrientes de los arboles de las hojas seniles no siempre es baja. Esta falta de consistencia en el resultado es talvez debida en parte a la metodología de reabsorción de nutrientes utilizada. El objetivo de este estudio fue analizar la reabsorción final de N y P de arboles de la selva húmeda tropical en un suelo rico en nutrientes. La hipótesis planteada fue que en un suelo rico en nutrientes los arboles presentarían una baja reabsorción final de

  7. Minerals Masquerading As Enzymes: Abiotic Oxidation Of Soil Organic Matter In An Iron-Rich Humid Tropical Forest Soil

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    Hall, S. J.; Silver, W. L.

    2010-12-01

    Oxidative reactions play an important role in decomposing soil organic matter fractions that resist hydrolytic degradation, and fundamentally affect the cycling of recalcitrant soil carbon across ecosystems. Microbial extracellular oxidative enzymes (e.g. lignin peroxidases and laccases) have been assumed to provide a dominant role in catalyzing soil organic matter oxidation, while other potential oxidative mechanisms remain poorly explored. Here, we show that abiotic reactions mediated by the oxidation of ferrous iron (Fe(II)) could explain high potential oxidation rates in humid tropical forest soils, which often contain high concentrations of Fe(II) and experience rapid redox fluctuations between anaerobic and aerobic conditions. These abiotic reactions could provide an additional mechanism to explain high rates of decomposition in these ecosystems, despite frequent oxygen deficits. We sampled humid tropical forest soils in Puerto Rico, USA from various topographic positions, ranging from well-drained ridges to riparian valleys that experience broad fluctuations in redox potential. We measured oxidative activity by adding the model humic compound L-DOPA to soil slurries, followed by colorimetric measurements of the supernatant solution over time. Dilute hydrogen peroxide was added to a subset of slurries to measure peroxidative activity. We found that oxidative and peroxidative activity correlated positively with soil Fe(II) concentrations, counter to prevailing theory that low redox potential should suppress oxidative enzymes. Boiling or autoclaving sub-samples of soil slurries to denature any enzymes present typically increased peroxidative activity and did not eliminate oxidative activity, further suggesting the importance of an abiotic mechanism. We found substantial differences in the oxidation products of the L-DOPA substrate generated by our soil slurries in comparison with oxidation products generated by a purified enzyme (mushroom tyrosinase

  8. Leaf and soil nitrogen and phosphorus availability in a neotropical rain forest of nutrient-rich soil

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    José Luis Martínez-Sánchez

    2006-06-01

    Full Text Available The nitrogen and phosphorus supply in a lowland rain forest with a nutrient-rich soil was investigated by means of the leaf N/P quotient. It was hypothesised a high N and P supply to the forest ecosystem with a N and P rich soil. Total N and extractable P were determined in the surface (10 cm soil of three plots of the forest. Total N was analysed by the Kjeldahl method, and P was extracted with HCl and NH4F. The leaf N/P quotient was evaluated from the senesced leaves of 11 dominant tree species from the mature forest. Samples of 5 g of freshly fallen leaves were collected from three trees of each species. Nitrogen was analysed by microkjeldahl digestion with sulphuric acid and distilled with boric acid, and phosphorus was analysed by digestion with nitric acid and perchloric acid, and determined by photometry. Concentrations of total N (0.50%, n = 30 and extractable P (4.11 μg g-1, n = 30 in the soil were high. As expected, P supply was sufficient, but contrary to expected, N supply was low (N/P = 11.8, n = 11. Rev. Biol. Trop. 54(2: 357-361. Epub 2006 Jun 01.A través del cociente foliar N/P, se investigó la disponibilidad de nitrógeno y fósforo en una selva húmeda tropical con suelo fértil. Como hipótesis se esperaba encontrar una alta disponibilidad de N y P en el ecosistema debido a un suelo rico en N y P. Se determinó el N total y el P extraible en el suelo superficial (10 cm en tres sitios de la selva. El N total se analizó por el método Kjeldahl y el P por extracción con HCl y NH4F. El cociente foliar N/P se evaluó a partir de hojas seniles de 11 especies arbóreas dominantes de la selva madura. Se recolectaron muestras de 5 g de hojas recién caídas de tres árboles de cada especie. El nitrógeno se analizó por digestión microkjeldahl con ácido sulfúrico y destilación con ácido bórico, y el fósforo por digestión con ácido nítrico y ácido perclórico, y determinación con fotometría. Las concetraciones de N

  9. Effects of soil water table regime on tree community species richness and structure of alluvial forest fragments in Southeast Brazil.

    Science.gov (United States)

    Silva, A C; Higuchi, P; van den Berg, E

    2010-08-01

    In order to determine the influence of soil water table fluctuation on tree species richness and structure of alluvial forest fragments, 24 plots were allocated in a point bar forest and 30 plots in five forest fragments located in a floodplain, in the municipality of São Sebastião da Bela Vista, Southeast Brazil, totalizing 54, 10 X 20 m, plots. The information recorded in each plot were the soil water table level, diameter at breast height (dbh), total height and botanical identity off all trees with dbh > 5 cm. The water table fluctuation was assessed through 1 m deep observation wells in each plot. Correlations analysis indicated that sites with shallower water table in the flooding plains had a low number of tree species and high tree density. Although the water table in the point bar remained below the wells during the study period, low tree species richness was observed. There are other events taking place within the point bar forest that assume a high ecological importance, such as the intensive water velocity during flooding and sedimentation processes.

  10. Effects of soil water table regime on tree community species richness and structure of alluvial forest fragments in Southeast Brazil

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    AC. Silva

    Full Text Available In order to determine the influence of soil water table fluctuation on tree species richness and structure of alluvial forest fragments, 24 plots were allocated in a point bar forest and 30 plots in five forest fragments located in a floodplain, in the municipality of São Sebastião da Bela Vista, Southeast Brazil, totalizing 54, 10 X 20 m, plots. The information recorded in each plot were the soil water table level, diameter at breast height (dbh, total height and botanical identity off all trees with dbh > 5 cm. The water table fluctuation was assessed through 1 m deep observation wells in each plot. Correlations analysis indicated that sites with shallower water table in the flooding plains had a low number of tree species and high tree density. Although the water table in the point bar remained below the wells during the study period, low tree species richness was observed. There are other events taking place within the point bar forest that assume a high ecological importance, such as the intensive water velocity during flooding and sedimentation processes.

  11. Covariation in plant functional traits and soil fertility within two species-rich forests.

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    Xiaojuan Liu

    Full Text Available The distribution of plant species along environmental gradients is expected to be predictable based on organismal function. Plant functional trait research has shown that trait values generally vary predictably along broad-scale climatic and soil gradients. This work has also demonstrated that at any one point along these gradients there is a large amount of interspecific trait variation. The present research proposes that this variation may be explained by the local-scale sorting of traits along soil fertility and acidity axes. Specifically, we predicted that trait values associated with high resource acquisition and growth rates would be found on soils that are more fertile and less acidic. We tested the expected relationships at the species-level and quadrat-level (20 × 20 m using two large forest plots in Panama and China that contain over 450 species combined. Predicted relationships between leaf area and wood density and soil fertility were supported in some instances, but the majority of the predicted relationships were rejected. Alternative resource axes, such as light gradients, therefore likely play a larger role in determining the interspecific variability in plant functional traits in the two forests studied.

  12. Disentangling the effects of climate, topography, soil and vegetation on stand-scale species richness in temperate forests

    OpenAIRE

    Zellweger Florian; Braunisch Veronika; Morsdorf Felix; Baltensweiler Andri; Abegg Meinrad; Roth Tobias; Bugmann Harald; Bollmann Kurt

    2015-01-01

    The growing awareness of biodiversity by forest managers has fueled the demand for information on abiotic and biotic factors that determine spatial biodiversity patterns. Detailed and area wide environmental data on potential predictors and site specific habitat characteristics however are usually not available across large spatial extents. Recent developments in environmental data acquisition such as the advent of Light Detection And Ranging (LiDAR) remote sensing provide opportunities to ch...

  13. Soil strength and forest operations

    OpenAIRE

    Beekman, F.

    1987-01-01

    The use of heavy machinery and transport vehicles is an integral part of modern forest operations. This use often causes damage to the standing trees and to the soil. In this study the effects of vehicle traffic on the soil are analysed and the possible consequences for forest management discussed. The study is largely restricted to sandy and loamy soils because of their importance for Dutch forestry.

    Soil strength, defined as the resistance of soil structure against the impa...

  14. Soil strength and forest operations

    NARCIS (Netherlands)

    Beekman, F.

    1987-01-01

    The use of heavy machinery and transport vehicles is an integral part of modern forest operations. This use often causes damage to the standing trees and to the soil. In this study the effects of vehicle traffic on the soil are analysed and the possible consequences for forest management

  15. Soil fauna as an indicator of soil quality in forest stands, pasture and secondary forest

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    Felipe Vieira da Cunha Neto

    2012-11-01

    Full Text Available The interactions between soil invertebrates and environmental variations are relatively unknown in the assessment of soil quality. The objective of this study was to evaluate soil quality in areas with different soil management systems, based on soil fauna as indicator, in Além Paraíba, Minas Gerais, Brazil. The soil invertebrate community was sampled using pitfall traps, in the dry and rainy seasons, from areas with five vegetation types (acacia, mimosa, eucalyptus, pasture, and secondary forest. The abundance of organisms and the total and average richness, Shannon's diversity index, the Pielou uniformity index, and change index V were determined. The fauna was most abundant in the areas of secondary forest and mimosa plantations in the dry season (111.3 and 31.7 individuals per trap per day, respectively. In the rainy season, the abundance of organisms in the three vegetation types did not differ. The highest values of average and total richness were recorded in the secondary forest in the dry season and in the mimosa stand in the rainy season. Shannon's index ranged from 1.57 in areas with acacia and eucalyptus in the rainy season to 3.19 in the eucalyptus area in the dry season. The uniformity index was highest in forest stands (eucalyptus, acacia and mimosa in the dry season, but higher in the rainy season in the pasture and secondary forest than in the forest stands. The change index V indicated that the percentage of extremely inhibited groups was lowest in the area with mimosa, both in the dry and rainy season (36 and 23 %, respectively. Of all forest stands, the mimosa area had the most abundant soil fauna.

  16. Landscape variation in tree species richness in northern Iran forests.

    Science.gov (United States)

    Bourque, Charles P-A; Bayat, Mahmoud

    2015-01-01

    Mapping landscape variation in tree species richness (SR) is essential to the long term management and conservation of forest ecosystems. The current study examines the prospect of mapping field assessments of SR in a high-elevation, deciduous forest in northern Iran as a function of 16 biophysical variables representative of the area's unique physiography, including topography and coastal placement, biophysical environment, and forests. Basic to this study is the development of moderate-resolution biophysical surfaces and associated plot-estimates for 202 permanent sampling plots. The biophysical variables include: (i) three topographic variables generated directly from the area's digital terrain model; (ii) four ecophysiologically-relevant variables derived from process models or from first principles; and (iii) seven variables of Landsat-8-acquired surface reflectance and two, of surface radiance. With symbolic regression, it was shown that only four of the 16 variables were needed to explain 85% of observed plot-level variation in SR (i.e., wind velocity, surface reflectance of blue light, and topographic wetness indices representative of soil water content), yielding mean-absolute and root-mean-squared error of 0.50 and 0.78, respectively. Overall, localised calculations of wind velocity and surface reflectance of blue light explained about 63% of observed variation in SR, with wind velocity accounting for 51% of that variation. The remaining 22% was explained by linear combinations of soil-water-related topographic indices and associated thresholds. In general, SR and diversity tended to be greatest for plots dominated by Carpinus betulus (involving ≥ 33% of all trees in a plot), than by Fagus orientalis (median difference of one species). This study provides a significant step towards describing landscape variation in SR as a function of modelled and satellite-based information and symbolic regression. Methods in this study are sufficiently general to be

  17. Long-term nitrogen addition decreases carbon leaching in a nitrogen-rich forest ecosystem

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    X. Lu

    2013-06-01

    Full Text Available Dissolved organic carbon (DOC plays a critical role in the carbon (C cycle of forest soils, and has been recently connected with global increases in nitrogen (N deposition. Most studies on effects of elevated N deposition on DOC have been carried out in N-limited temperate regions, with far fewer data available from N-rich ecosystems, especially in the context of chronically elevated N deposition. Furthermore, mechanisms for excess N-induced changes of DOC dynamics have been suggested to be different between the two kinds of ecosystems, because of the different ecosystem N status. The purpose of this study was to experimentally examine how long-term N addition affects DOC dynamics below the primary rooting zones (the upper 20 cm soils in typically N-rich lowland tropical forests. We have a primary assumption that long-term continuous N addition minimally affects DOC concentrations and effluxes in N-rich tropical forests. Experimental N addition was administered at the following levels: 0, 50, 100 and 150 kg N ha−1 yr−1, respectively. Results showed that seven years of N addition significantly decreased DOC concentrations in soil solution, and chemo-physical controls (solution acidity change and soil sorption rather than biological controls may mainly account for the decreases, in contrast to other forests. We further found that N addition greatly decreased annual DOC effluxes from the primary rooting zone and increased water-extractable DOC in soils. Our results suggest that long-term N deposition could increase soil C sequestration in the upper soils by decreasing DOC efflux from that layer in N-rich ecosystems, a novel mechanism for continued accumulation of soil C in old-growth forests.

  18. Proceedings of the California Forest Soils Council Conference on Forest Soils Biology and Forest Management

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    Robert F. Powers; Donald L. Hauxwell; Gary M. Nakamura

    2000-01-01

    Biotic properties of forest soil are the linkages connecting forest vegetation with an inert rooting medium to create a dynamic, functioning ecosystem. But despite the significance of these properties, managers have little awareness of the biotic world beneath their feet. Much of our working knowledge of soil biology seems anchored in myth and misunderstanding. To...

  19. Butterfly Species Richness in Selected West Albertine Rift Forests

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    Patrice Kasangaki

    2012-01-01

    Full Text Available The butterfly species richness of 17 forests located in the western arm of the Albertine Rift in Uganda was compared using cluster analysis and principal components analysis (PCA to assess similarities among the forests. The objective was to compare the butterfly species richness of the forests. A total of 630 butterfly species were collected in 5 main families. The different species fell into 7 ecological groupings with the closed forest group having the most species and the swamp/wetland group with the fewest number of species. Three clusters were obtained. The first cluster had forests characterized by relatively high altitude and low species richness despite the big area in the case of Rwenzori and being close to the supposed Pleistocene refugium. The second cluster had forests far away from the supposed refugium except Kisangi and moderate species richness with small areas, whereas the third cluster had those forests that were more disturbed, high species richness, and low altitudinal levels with big areas.

  20. Increased forest ecosystem carbon and nitrogen storage from nitrogen rich bedrock.

    Science.gov (United States)

    Morford, Scott L; Houlton, Benjamin Z; Dahlgren, Randy A

    2011-08-31

    Nitrogen (N) limits the productivity of many ecosystems worldwide, thereby restricting the ability of terrestrial ecosystems to offset the effects of rising atmospheric CO(2) emissions naturally. Understanding input pathways of bioavailable N is therefore paramount for predicting carbon (C) storage on land, particularly in temperate and boreal forests. Paradigms of nutrient cycling and limitation posit that new N enters terrestrial ecosystems solely from the atmosphere. Here we show that bedrock comprises a hitherto overlooked source of ecologically available N to forests. We report that the N content of soils and forest foliage on N-rich metasedimentary rocks (350-950 mg N kg(-1)) is elevated by more than 50% compared with similar temperate forest sites underlain by N-poor igneous parent material (30-70 mg N kg(-1)). Natural abundance N isotopes attribute this difference to rock-derived N: (15)N/(14)N values for rock, soils and plants are indistinguishable in sites underlain by N-rich lithology, in marked contrast to sites on N-poor substrates. Furthermore, forests associated with N-rich parent material contain on average 42% more carbon in above-ground tree biomass and 60% more carbon in the upper 30 cm of the soil than similar sites underlain by N-poor rocks. Our results raise the possibility that bedrock N input may represent an important and overlooked component of ecosystem N and C cycling elsewhere.

  1. Estimating tree species richness from forest inventory plot data

    Science.gov (United States)

    Ronald E. McRoberts; Dacia M. Meneguzzo

    2007-01-01

    Montreal Process Criterion 1, Conservation of Biological Diversity, expresses species diversity in terms of number of forest dependent species. Species richness, defined as the total number of species present, is a common metric for analyzing species diversity. A crucial difficulty in estimating species richness from sample data obtained from sources such as inventory...

  2. Landscape variation in tree species richness in northern Iran forests.

    Directory of Open Access Journals (Sweden)

    Charles P-A Bourque

    Full Text Available Mapping landscape variation in tree species richness (SR is essential to the long term management and conservation of forest ecosystems. The current study examines the prospect of mapping field assessments of SR in a high-elevation, deciduous forest in northern Iran as a function of 16 biophysical variables representative of the area's unique physiography, including topography and coastal placement, biophysical environment, and forests. Basic to this study is the development of moderate-resolution biophysical surfaces and associated plot-estimates for 202 permanent sampling plots. The biophysical variables include: (i three topographic variables generated directly from the area's digital terrain model; (ii four ecophysiologically-relevant variables derived from process models or from first principles; and (iii seven variables of Landsat-8-acquired surface reflectance and two, of surface radiance. With symbolic regression, it was shown that only four of the 16 variables were needed to explain 85% of observed plot-level variation in SR (i.e., wind velocity, surface reflectance of blue light, and topographic wetness indices representative of soil water content, yielding mean-absolute and root-mean-squared error of 0.50 and 0.78, respectively. Overall, localised calculations of wind velocity and surface reflectance of blue light explained about 63% of observed variation in SR, with wind velocity accounting for 51% of that variation. The remaining 22% was explained by linear combinations of soil-water-related topographic indices and associated thresholds. In general, SR and diversity tended to be greatest for plots dominated by Carpinus betulus (involving ≥ 33% of all trees in a plot, than by Fagus orientalis (median difference of one species. This study provides a significant step towards describing landscape variation in SR as a function of modelled and satellite-based information and symbolic regression. Methods in this study are sufficiently

  3. Isolation and identification of soil fungi isolates from forest soil for flooded soil recovery

    Science.gov (United States)

    Hazwani Aziz, Nor; Zainol, Norazwina

    2018-04-01

    Soil fungi have been evaluated for their ability in increasing and recovering nitrogen, phosphorus and potassium content in flooded soil and in promoting the growth of the host plant. Host plant was cultivated in a mixture of fertile forest soil (nutrient-rich soil) and simulated flooded soil (nutrient-poor soil) in an optimized soil condition for two weeks. The soil sample was harvested every day until two weeks of planting and was tested for nitrogen, phosphorus and potassium concentration. Soil fungi were isolated by using dilution plating technique and was identified by Biolog’s Microbial Systems. The concentration of nitrogen, phosphorus, and potassium was found to be increasing after two weeks by two to three times approximately from the initial concentration recorded. Two fungi species were identified with probability more than 90% namely Aspergillus aculeatus and Paecilomyces lilacinus. Both identified fungi were found to be beneficial in enhancing plant growth and increasing the availability of nutrient content in the soil and thus recovering the nutrient content in the flooded soil.

  4. Mangroves among the most carbon-rich forests in the tropics

    Science.gov (United States)

    Donato, Daniel C.; Kauffman, J. Boone; Murdiyarso, Daniel; Kurnianto, Sofyan; Stidham, Melanie; Kanninen, Markku

    2011-05-01

    Mangrove forests occur along ocean coastlines throughout the tropics, and support numerous ecosystem services, including fisheries production and nutrient cycling. However, the areal extent of mangrove forests has declined by 30-50% over the past half century as a result of coastal development, aquaculture expansion and over-harvesting. Carbon emissions resulting from mangrove loss are uncertain, owing in part to a lack of broad-scale data on the amount of carbon stored in these ecosystems, particularly below ground. Here, we quantified whole-ecosystem carbon storage by measuring tree and dead wood biomass, soil carbon content, and soil depth in 25 mangrove forests across a broad area of the Indo-Pacific region--spanning 30° of latitude and 73° of longitude--where mangrove area and diversity are greatest. These data indicate that mangroves are among the most carbon-rich forests in the tropics, containing on average 1,023Mg carbon per hectare. Organic-rich soils ranged from 0.5m to more than 3m in depth and accounted for 49-98% of carbon storage in these systems. Combining our data with other published information, we estimate that mangrove deforestation generates emissions of 0.02-0.12Pg carbon per year--as much as around 10% of emissions from deforestation globally, despite accounting for just 0.7% of tropical forest area.

  5. Dynamics of forest soil chemistry

    Energy Technology Data Exchange (ETDEWEB)

    Alveteg, M

    1998-11-01

    Acidification caused by emissions of nitrogen and sulphur and associated adverse effects on forest ecosystems has been an issue on the political agenda for decades. Temporal aspects of soil acidification and/or recovery can be investigated using the soil chemistry model SAFE, a dynamic version of the steady-state model PROFILE used in critical loads assessment on the national level, e.g. for Sweden. In this thesis, possibilities to replace the use of apparent gibbsite solubility coefficients with a more mechanistic Al sub-model are investigated and a reconstruction model, MAKEDEP, is presented which makes hindcasts and forecasts of atmospheric deposition and nutrient uptake and cycling. A regional application of SAFE/MAKEDEP based on 622 sites in Switzerland is also presented. It is concluded that the quantitative information on pools and fluxes of Al in forest ecosystems is very limited and that there currently exists no mechanistic alternative in modelling soil solution Al. MAKEDEP is a valuable and operational tool for deriving input to dynamic soil chemistry models such as SMART, MAGIC and SAFE. For multi-layer models, e.g. the SAFE model, including nutrient cycling in MAKEDEP is shown to be important. The strength of the regional assessment strategy presented in this thesis lies in its transparency and modularity. All sub-modules, including models, transfer functions, assumptions in the data acquisition strategy, etc., can be checked and replaced individually. As the presented assessment strategy is based on knowledge and data from a wide range of scientists and fields it is of vital importance that the research community challenge the assumptions made. The many measurable intermediate results produced by the included models will hopefully encourage scientists to challenge the models through additional measurements at the calculation sites. It is concluded that current reduction plans are not sufficient for all forest ecosystems in Switzerland to recover from

  6. Mechanisms controlling radionuclide mobility in forest soils

    International Nuclear Information System (INIS)

    Delvaux, B.; Kruyts, N.; Maes, E.; Agapkina, G.I.; Kliashtorin, A.; Bunzl, K.; Rafferty, B.

    1996-01-01

    Soil processes strongly influence the radionuclide mobility in soils. The mobility of radionuclides in forest soils is governed by several processes involving both abiotic and biotic factors. The sorption-desorption process chiefly governs the activity of radionuclides in the soil solution, hence thereby their mobility and biological availability. Radiocaesium exhibits a very low mobility in mineral soils. Both mobility and bioavailability however increase as the thickness of organic layers and their content in organic matter increases. Clay minerals of micaceous origin strongly act as slinks for radiocaesium in forest soils. The magnitude of cesium mineral fixation in topsoils is expected to be the highest in mineral soils of Eutric cambisol type, and, to a lesser extent, of type of Distric cambisol and Podzoluvisol. A low mobility of radiocaesium in the surface horizons of forest soils may also be partially explained by a biological mobilization: fungi absorb radiocaesium and transport it to upper layers, thereby contributing to constantly recycle the radioelement in the organic horizons. This mechanism is probably important in soils with thick organic layers (Podsol, Histosol, and, to a lesser extent, Distric cambisol and Podzoluvisol). Radionuclides can be associated with soluble organic anions in the soil solution of forest acid soils. Such associations are highly mobile: they are stable in conditions of poor biological activity (low temperatures, acid soil infertility, water excess, etc.). Their magnitude is expected to be the highest in thick acid organic layers (soils of type Podzol and Histosol)

  7. Ant species richness of fynbos and forest ecosystems in the ...

    African Journals Online (AJOL)

    The ant fauna in fynbos and forest habitats in the southern Cape are compared. There is no significant difference in ant species richness between the two undisturbed habitat types, and the only two species common to both are Acantholepis capensis and Camponotus maculatus. The degree of Hakea sericea infestation in ...

  8. 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

  9. 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

  10. Nitrogen release from forest soils containing sulfide-bearing sediments

    Science.gov (United States)

    Maileena Nieminen, Tiina; Merilä, Päivi; Ukonmaanaho, Liisa

    2014-05-01

    Soils containing sediments dominated by metal sulfides cause high acidity and release of heavy metals, when excavated or drained, as the aeration of these sediments causes formation of sulfuric acid. Consequent leaching of acidity and heavy metals can kill tree seedlings and animals such as fish, contaminate water, and corrode concrete and steel. These types of soils are called acid sulfate soils. Their metamorphic equivalents, such as sulfide rich black shales, pose a very similar risk of acidity and metal release to the environment. Until today the main focus in treatment of the acid sulfate soils has been to prevent acidification and metal toxicity to agricultural crop plants, and only limited attention has been paid to the environmental threat caused by the release of acidity and heavy metals to the surrounding water courses. Even less attention is paid on release of major nutrients, such as nitrogen, although these sediments are extremely rich in carbon and nitrogen and present a potentially high microbiological activity. In Europe, the largest cover of acid sulfate soils is found in coastal lowlands of Finland. Estimates of acid sulfate soils in agricultural use range from 1 300 to 3 000 km2, but the area in other land use classes, such as managed peatland forests, is presumably larger. In Finland, 49 500 km2 of peatlands have been drained for forestry, and most of these peatland forests will be at the regeneration stage within 10 to 30 years. As ditch network maintenance is often a prerequisite for a successful establishment of the following tree generation, the effects of maintenance operations on the quality of drainage water should be under special control in peatlands underlain by sulfide-bearing sediments. Therefore, identification of risk areas and effective prevention of acidity and metal release during drain maintenance related soil excavating are great challenges for forestry on coastal lowlands of Finland. The organic and inorganic nitrogen

  11. Upscaling species richness and abundances in tropical forests.

    Science.gov (United States)

    Tovo, Anna; Suweis, Samir; Formentin, Marco; Favretti, Marco; Volkov, Igor; Banavar, Jayanth R; Azaele, Sandro; Maritan, Amos

    2017-10-01

    The quantification of tropical tree biodiversity worldwide remains an open and challenging problem. More than two-fifths of the number of worldwide trees can be found either in tropical or in subtropical forests, but only ≈0.000067% of species identities are known. We introduce an analytical framework that provides robust and accurate estimates of species richness and abundances in biodiversity-rich ecosystems, as confirmed by tests performed on both in silico-generated and real forests. Our analysis shows that the approach outperforms other methods. In particular, we find that upscaling methods based on the log-series species distribution systematically overestimate the number of species and abundances of the rare species. We finally apply our new framework on 15 empirical tropical forest plots and quantify the minimum percentage cover that should be sampled to achieve a given average confidence interval in the upscaled estimate of biodiversity. Our theoretical framework confirms that the forests studied are comprised of a large number of rare or hyper-rare species. This is a signature of critical-like behavior of species-rich ecosystems and can provide a buffer against extinction.

  12. Ectomycorrhizal mats alter forest soil biogeochemistry

    Science.gov (United States)

    Laurel A. Kluber; Kathryn M. Tinnesand; Bruce A. Caldwell; Susie M. Dunham; Rockie R. Yarwood; Peter J. Bottomley; David D. Myrold

    2010-01-01

    Dense hyphal mats formed by ectomycorrhizal (EcM) fungi are prominent features in Douglas-fir forest ecosystems, and have been estimated to cover up to 40% of the soil surface in some forest stands. Two morphotypes of EcM mats have been previously described: rhizomorphic mats, which have thick hyphal rhizomorphs and are found primarily in the organic horizon, and...

  13. Water availability determines the richness and density of fig trees within Brazilian semideciduous forest landscapes

    Science.gov (United States)

    Coelho, Luís Francisco Mello; Ribeiro, Milton Cezar; Pereira, Rodrigo Augusto Santinelo

    2014-05-01

    The success of fig trees in tropical ecosystems is evidenced by the great diversity (+750 species) and wide geographic distribution of the genus. We assessed the contribution of environmental variables on the species richness and density of fig trees in fragments of seasonal semideciduous forest (SSF) in Brazil. We assessed 20 forest fragments in three regions in Sao Paulo State, Brazil. Fig tree richness and density was estimated in rectangular plots, comprising 31.4 ha sampled. Both richness and fig tree density were linearly modeled as function of variables representing (1) fragment metrics, (2) forest structure, and (3) landscape metrics expressing water drainage in the fragments. Model selection was performed by comparing the AIC values (Akaike Information Criterion) and the relative weight of each model (wAIC). Both species richness and fig tree density were better explained by the water availability in the fragment (meter of streams/ha): wAICrichness = 0.45, wAICdensity = 0.96. The remaining variables related to anthropic perturbation and forest structure were of little weight in the models. The rainfall seasonality in SSF seems to select for both establishment strategies and morphological adaptations in the hemiepiphytic fig tree species. In the studied SSF, hemiepiphytes established at lower heights in their host trees than reported for fig trees in evergreen rainforests. Some hemiepiphytic fig species evolved superficial roots extending up to 100 m from their trunks, resulting in hectare-scale root zones that allow them to efficiently forage water and soil nutrients. The community of fig trees was robust to variation in forest structure and conservation level of SSF fragments, making this group of plants an important element for the functioning of seasonal tropical forests.

  14. Disturbance alters local-regional richness relationships in appalachian forests

    Science.gov (United States)

    Belote, R.T.; Sanders, N.J.; Jones, R.H.

    2009-01-01

    Whether biological diversity within communities is limited by local interactions or regional species pools remains an important question in ecology. In this paper, we investigate how an experimentally applied tree-harvesting disturbance gradient influenced local-regional richness relationships. Plant species richness was measured at three spatial scales (2 ha = regional; 576 m2 and 1 m2 = local) on three occasions (one year pre-disturbance, one year post-disturbance, and 10 years post-disturbance) across five disturbance treatments (uncut control through clearcut) replicated throughout the southern Appalachian Mountains, USA. We investigated whether species richness in 576-m2 plots and 1-m2 subplots depended on species richness in 2-ha experimental units and whether this relationship changed through time before and after canopy disturbance. We found that, before disturbance, the relationship between local and regional richness was weak or nonexistent. One year after disturbance local richness was a positive function of regional richness, because local sites were colonized from the regional species pool. Ten years after disturbance, the positive relationship persisted, but the slope had decreased by half. These results suggest that disturbance can set the stage for strong influences of regional species pools on local community assembly in temperate forests. However, as time since disturbance increases, local controls on community assembly decouple the relationships between regional and local diversity. ?? 2009 by the Ecological Society of America.

  15. Forest management type influences diversity and community composition of soil fungi across temperate forest ecosystems

    Directory of Open Access Journals (Sweden)

    Kezia eGoldmann

    2015-11-01

    Full Text Available Fungal communities have been shown to be highly sensitive towards shifts in plant diversity and species composition in forest ecosystems. However, little is known about the impact of forest management on fungal diversity and community composition of geographically separated sites. This study examined the effects of four different forest management types on soil fungal communities. These forest management types include age class forests of young managed beech (Fagus sylvatica L., with beech stands age of approximately 30 years, age class beech stands with an age of approximately 70 years, unmanaged beech stands, and coniferous stands dominated by either pine (Pinus sylvestris L. or spruce (Picea abies Karst. which are located in three study sites across Germany. Soil were sampled from 48 study plots and we employed fungal ITS rDNA pyrotag sequencing to assess the soil fungal diversity and community structure.We found that forest management type significantly affects the Shannon diversity of soil fungi and a significant interaction effect of study site and forest management on the fungal OTU richness. Consequently distinct fungal communities were detected in the three study sites and within the four forest management types, which were mainly related to the main tree species. Further analysis of the contribution of soil properties revealed that C/N ratio being the most important factor in all the three study sites whereas soil pH was significantly related to the fungal community in two study sites. Functional assignment of the fungal communities indicated that 38% of the observed communities were Ectomycorrhizal fungi (ECM and their distribution is significantly influenced by the forest management. Soil pH and C/N ratio were found to be the main drivers of the ECM fungal community composition. Additional fungal community similarity analysis revealed the presence of study site and management type specific ECM genera.This study extends our knowledge

  16. Forest Management Type Influences Diversity and Community Composition of Soil Fungi across Temperate Forest Ecosystems.

    Science.gov (United States)

    Goldmann, Kezia; Schöning, Ingo; Buscot, François; Wubet, Tesfaye

    2015-01-01

    Fungal communities have been shown to be highly sensitive toward shifts in plant diversity and species composition in forest ecosystems. However, little is known about the impact of forest management on fungal diversity and community composition of geographically separated sites. This study examined the effects of four different forest management types on soil fungal communities. These forest management types include age class forests of young managed beech (Fagus sylvatica L.), with beech stands age of approximately 30 years, age class beech stands with an age of approximately 70 years, unmanaged beech stands, and coniferous stands dominated by either pine (Pinus sylvestris L.) or spruce (Picea abies Karst.) which are located in three study sites across Germany. Soil were sampled from 48 study plots and we employed fungal ITS rDNA pyrotag sequencing to assess the soil fungal diversity and community structure. We found that forest management type significantly affects the Shannon diversity of soil fungi and a significant interaction effect of study site and forest management on the fungal operational taxonomic units richness. Consequently distinct fungal communities were detected in the three study sites and within the four forest management types, which were mainly related to the main tree species. Further analysis of the contribution of soil properties revealed that C/N ratio being the most important factor in all the three study sites whereas soil pH was significantly related to the fungal community in two study sites. Functional assignment of the fungal communities indicated that 38% of the observed communities were Ectomycorrhizal fungi (ECM) and their distribution is significantly influenced by the forest management. Soil pH and C/N ratio were found to be the main drivers of the ECM fungal community composition. Additional fungal community similarity analysis revealed the presence of study site and management type specific ECM genera. This study extends our

  17. The soil indicator of forest health in the Forest Inventory and Analysis Program

    Science.gov (United States)

    Michael C. Amacher; Charles H. Perry

    2010-01-01

    Montreal Process Criteria and Indicators (MPCI) were established to monitor forest conditions and trends to promote sustainable forest management. The Soil Indicator of forest health was developed and implemented within the USFS Forest Inventory and Analysis (FIA) program to assess condition and trends in forest soil quality in U.S. forests regardless of ownership. The...

  18. Fumigant distribution in forest nursery soils

    Science.gov (United States)

    Dong Wang; Stephen W. Fraedrich; Jennifer Juzwik; Kurt Spokas; Yi Zhang; William C. Koskinen

    2006-01-01

    Adequate concentration, exposure time and distribution uniformity of activated fumigant gases are prerequisites for successful soil fumigation. Field experiments were conducted to evaluate gas phase distributions of methyl isothiocyanate (MITC) and chloropicrin (CP) in two forest-tree nurseries. Concentrations of MITC and CP in soil air were measured from replicated...

  19. Alkali metals in fungi of forest soil

    International Nuclear Information System (INIS)

    Vinichuk, M.; Taylor, A.; Rosen, K.; Nikolova, I.; Johanson, K.J.

    2009-01-01

    The high affinity of forest soil fungi for alkali metals such as potassium, rubidium, caesium as well as radiocaesium is shown and discussed. Good positive correlation was found between K: Rb concentration ratios in soil and in fungi, when correlation between K: Cs concentration ratios was less pronounced. (LN)

  20. Does species richness affect fine root biomass and production in young forest plantations?

    Science.gov (United States)

    Domisch, Timo; Finér, Leena; Dawud, Seid Muhie; Vesterdal, Lars; Raulund-Rasmussen, Karsten

    2015-02-01

    Tree species diversity has been reported to increase forest ecosystem above-ground biomass and productivity, but little is known about below-ground biomass and production in diverse mixed forests compared to single-species forests. For testing whether species richness increases below-ground biomass and production and thus complementarity between forest tree species in young stands, we determined fine root biomass and production of trees and ground vegetation in two experimental plantations representing gradients in tree species richness. Additionally, we measured tree fine root length and determined species composition from fine root biomass samples with the near-infrared reflectance spectroscopy method. We did not observe higher biomass or production in mixed stands compared to monocultures. Neither did we observe any differences in tree root length or fine root turnover. One reason for this could be that these stands were still young, and canopy closure had not always taken place, i.e. a situation where above- or below-ground competition did not yet exist. Another reason could be that the rooting traits of the tree species did not differ sufficiently to support niche differentiation. Our results suggested that functional group identity (i.e. conifers vs. broadleaved species) can be more important for below-ground biomass and production than the species richness itself, as conifers seemed to be more competitive in colonising the soil volume, compared to broadleaved species.

  1. Soil moisture in sessile oak forest gaps

    Science.gov (United States)

    Zagyvainé Kiss, Katalin Anita; Vastag, Viktor; Gribovszki, Zoltán; Kalicz, Péter

    2015-04-01

    By social demands are being promoted the aspects of the natural forest management. In forestry the concept of continuous forest has been an accepted principle also in Hungary since the last decades. The first step from even-aged stand to continuous forest can be the forest regeneration based on gap cutting, so small openings are formed in a forest due to forestry interventions. This new stand structure modifies the hydrological conditions for the regrowth. Without canopy and due to the decreasing amounts of forest litter the interception is less significant so higher amount of precipitation reaching the soil. This research focuses on soil moisture patterns caused by gaps. The spatio-temporal variability of soil water content is measured in gaps and in surrounding sessile oak (Quercus petraea) forest stand. Soil moisture was determined with manual soil moisture meter which use Time-Domain Reflectometry (TDR) technology. The three different sizes gaps (G1: 10m, G2: 20m, G3: 30m) was opened next to Sopron on the Dalos Hill in Hungary. First, it was determined that there is difference in soil moisture between forest stand and gaps. Second, it was defined that how the gap size influences the soil moisture content. To explore the short term variability of soil moisture, two 24-hour (in growing season) and a 48-hour (in dormant season) field campaign were also performed in case of the medium-sized G2 gap along two/four transects. Subdaily changes of soil moisture were performed. The measured soil moisture pattern was compared with the radiation pattern. It was found that the non-illuminated areas were wetter and in the dormant season the subdaily changes cease. According to our measurements, in the gap there is more available water than under the forest stand due to the less evaporation and interception loss. Acknowledgements: The research was supported by TÁMOP-4.2.2.A-11/1/KONV-2012-0004 and AGRARKLIMA.2 VKSZ_12-1-2013-0034.

  2. Plant species richness regulates soil respiration through changes in productivity.

    Science.gov (United States)

    Dias, André Tavares Corrêa; van Ruijven, Jasper; Berendse, Frank

    2010-07-01

    Soil respiration is an important pathway of the C cycle. However, it is still poorly understood how changes in plant community diversity can affect this ecosystem process. Here we used a long-term experiment consisting of a gradient of grassland plant species richness to test for effects of diversity on soil respiration. We hypothesized that plant diversity could affect soil respiration in two ways. On the one hand, more diverse plant communities have been shown to promote plant productivity, which could increase soil respiration. On the other hand, the nutrient concentration in the biomass produced has been shown to decrease with diversity, which could counteract the production-induced increase in soil respiration. Our results clearly show that soil respiration increased with species richness. Detailed analysis revealed that this effect was not due to differences in species composition. In general, soil respiration in mixtures was higher than would be expected from the monocultures. Path analysis revealed that species richness predominantly regulates soil respiration through changes in productivity. No evidence supporting the hypothesized negative effect of lower N concentration on soil respiration was found. We conclude that shifts in productivity are the main mechanism by which changes in plant diversity may affect soil respiration.

  3. Molecular characterization of soil bacterial community in a perhumid, low mountain forest.

    Science.gov (United States)

    Lin, Yu-Te; Whitman, William B; Coleman, David C; Chih-Yu, Chiu

    2011-01-01

    Forest disturbance often results in changes in soil properties and microbial communities. In the present study, we characterized a soil bacterial community subjected to disturbance using 16S rRNA gene clone libraries. The community was from a disturbed broad-leaved, low mountain forest ecosystem at Huoshaoliao (HSL) located in northern Taiwan. This locality receives more than 4,000 mm annual precipitation, one of the highest precipitations in Taiwan. Based on the Shannon diversity index, Chao1 estimator, richness and rarefaction curve analysis, the bacterial community in HSL forest soils was more diverse than those previously investigated in natural and disturbed forest soils with colder or less humid weather conditions. Analysis of molecular variance also revealed that the bacterial community in disturbed soils significantly differed from natural forest soils. Most of the abundant operational taxonomic units (OTUs) in the disturbed soil community at HSL were less abundant or absent in other soils. The disturbances influenced the composition of bacterial communities in natural and disturbed forests and increased the diversity of the disturbed forest soil community. Furthermore, the warmer and humid weather conditions could also increase community diversity in HSL soils.

  4. Formation of chloroform in spruce forest soil - results from laboratory incubation studies

    DEFF Research Database (Denmark)

    Haselmann, K.F.; Laturnus, F.; Svensmark, B.

    2000-01-01

    The release of chloroform, 1,1,1-trichloroethane, tetrachloromethane, trichloroethene and tetrachloroethene from an organic rich spruce forest soil was studied in laboratory incubation experiments by dynamic headspace analysis, thermodesorption and gas chromatography. Performance parameters...... are presented for the dynamic headspace system. For spruce forest soil, the results showed a significant increase in chloroform concentration in the headspace under aerobic conditions over a period of seven days, whereas the concentration of the other compounds remained fairly constant. A biogenic formation...

  5. Mapping and predictive variations of soil bacterial richness across France.

    Directory of Open Access Journals (Sweden)

    Sébastien Terrat

    Full Text Available Although numerous studies have demonstrated the key role of bacterial diversity in soil functions and ecosystem services, little is known about the variations and determinants of such diversity on a nationwide scale. The overall objectives of this study were i to describe the bacterial taxonomic richness variations across France, ii to identify the ecological processes (i.e. selection by the environment and dispersal limitation influencing this distribution, and iii to develop a statistical predictive model of soil bacterial richness. We used the French Soil Quality Monitoring Network (RMQS, which covers all of France with 2,173 sites. The soil bacterial richness (i.e. OTU number was determined by pyrosequencing 16S rRNA genes and related to the soil characteristics, climatic conditions, geomorphology, land use and space. Mapping of bacterial richness revealed a heterogeneous spatial distribution, structured into patches of about 111km, where the main drivers were the soil physico-chemical properties (18% of explained variance, the spatial descriptors (5.25%, 1.89% and 1.02% for the fine, medium and coarse scales, respectively, and the land use (1.4%. Based on these drivers, a predictive model was developed, which allows a good prediction of the bacterial richness (R2adj of 0.56 and provides a reference value for a given pedoclimatic condition.

  6. Mapping and predictive variations of soil bacterial richness across France.

    Science.gov (United States)

    Terrat, Sébastien; Horrigue, Walid; Dequiedt, Samuel; Saby, Nicolas P A; Lelièvre, Mélanie; Nowak, Virginie; Tripied, Julie; Régnier, Tiffanie; Jolivet, Claudy; Arrouays, Dominique; Wincker, Patrick; Cruaud, Corinne; Karimi, Battle; Bispo, Antonio; Maron, Pierre Alain; Chemidlin Prévost-Bouré, Nicolas; Ranjard, Lionel

    2017-01-01

    Although numerous studies have demonstrated the key role of bacterial diversity in soil functions and ecosystem services, little is known about the variations and determinants of such diversity on a nationwide scale. The overall objectives of this study were i) to describe the bacterial taxonomic richness variations across France, ii) to identify the ecological processes (i.e. selection by the environment and dispersal limitation) influencing this distribution, and iii) to develop a statistical predictive model of soil bacterial richness. We used the French Soil Quality Monitoring Network (RMQS), which covers all of France with 2,173 sites. The soil bacterial richness (i.e. OTU number) was determined by pyrosequencing 16S rRNA genes and related to the soil characteristics, climatic conditions, geomorphology, land use and space. Mapping of bacterial richness revealed a heterogeneous spatial distribution, structured into patches of about 111km, where the main drivers were the soil physico-chemical properties (18% of explained variance), the spatial descriptors (5.25%, 1.89% and 1.02% for the fine, medium and coarse scales, respectively), and the land use (1.4%). Based on these drivers, a predictive model was developed, which allows a good prediction of the bacterial richness (R2adj of 0.56) and provides a reference value for a given pedoclimatic condition.

  7. Relief influence on tree species richness in secondary forest fragments of Atlantic Forest, SE, Brazil

    OpenAIRE

    Silva,William Goulart da; Metzger,Jean Paul; Bernacci,Luis Carlos; Catharino,Eduardo Luís Martins; Durigan,Giselda; Simões,Sílvio

    2008-01-01

    The aim of this work was to explore the relationship between tree species richness and morphological characteristics of relief at the Ibiúna Plateau (SE Brazil). We sampled 61 plots of 0.30 ha, systematically established in 20 fragments of secondary forest (2-274 ha) and in three areas within a continuous secondary forest site, Morro Grande Reserve (9,400 ha). At each plot, 100 trees with diameter at breast height > 5 cm were sampled by the point centered quarter method, and total richness an...

  8. Forest structure, diversity and soil properties in a dry tropical forest in Rajasthan, Western India

    Directory of Open Access Journals (Sweden)

    J. I. Nirmal Kumar

    2011-06-01

    Full Text Available Structure, species composition, and soil properties of a dry tropical forest in Rajasthan Western India, were examined by establishment of 25 plots. The forest was characterized by a relatively low canopy and a large number of small-diameter trees. Mean canopy height for this forest was 10 m and stands contained an average of 995 stems ha-1 (= 3.0 cm DBH; 52% of those stems were smaller than 10 cm DBH. The total basal area was 46.35 m2ha-1, of which Tectona grandis L. contributed 48%. The forest showed high species diversity of trees. 50 tree species (= 3.0 cm DBH from 29 families were identified in the 25 sampling plots. T. grandis (20.81% and Butea monosperma (9% were the dominant and subdominant species in terms of importance value. The mean tree species diversity indices for the plots were 1.08 for Shannon diversity index (H´, 0.71 for equitability index (J´ and 5.57 for species richness index (S´, all of which strongly declined with the increase of importance value of the dominant, T. grandis. Measures of soil nutrients indicated low fertility, extreme heterogeneity. Regression analysis showed that stem density and the dominant tree height were significantly correlated with soil pH. There was a significant positive relationship between species diversity index and soil available P, exchangeable K+, Ca2+ (all p values < 0.001 and a negative relationship with N, C, C:N and C:P ratio. The results suggest that soil properties are major factors influencing forest composition and structure within the dry tropical forest in Rajasthan.

  9. Gaseous mercury fluxes from forest soils in response to forest harvesting intensity: A field manipulation experiment

    Science.gov (United States)

    M. Mazur; C.P.J. Mitchell; C.S. Eckley; S.L. Eggert; R.K. Kolka; S.D. Sebestyen; E.B. Swain

    2014-01-01

    Forest harvesting leads to changes in soil moisture, temperature and incident solar radiation, all strong environmental drivers of soil-air mercury (Hg) fluxes. Whether different forest harvesting practices significantly alter Hg fluxes from forest soils is unknown.We conducted a field-scale experiment in a northern Minnesota deciduous forest wherein gaseous Hg...

  10. Towards an ecologically sustainable energy production based on forest biomass - Forest fertilisation with nutrient rich organic waste matter

    Energy Technology Data Exchange (ETDEWEB)

    Roegaard, Pia-Maria; Aakerback, Nina; Sahlen, Kenneth; Sundell, Markus [Swedish Polytechnic, Vasa (Finland)

    2006-07-15

    The project is a collaboration between Swedish Univ. of Agricultural Sciences, Faculty of Forest Sciences in Umeaa, Swedish Polytechnic, Finland in Vaasa and the Finnish Forest Research Institute in Kannus. Today there are pronounced goals within the EU that lead towards an ecologically sustainable community and there is also a global goal to decrease net carbon dioxide emissions. These goals involve among other things efforts to increase the use of renewable biofuel as energy source. This will result in an enlarged demand for biomass for energy production. Therefore, the forest resources in the Nordic countries will be required for energy production to a far greater extent in the future. One way to meet this increased tree biomass demand is to increase forest tree growth through supply of nutrients, of which nitrogen is the most important. Organic nutrient rich waste matter from the society, such as sewage sludge and mink and fox manure compost from fur farms might be used as forest fertilizer. This would result in increased supply of renewable tree biomass, decreased net carbon dioxide emissions, increased forest ecosystem carbon sequestration, decreased methane emissions from sewage sludge landfill and decreased society costs for sludge landfill or incineration. Therefore, the purpose of this project is to develop methods for forest fertilisation with nutrient rich organic waste matter from municipal wastewater, sludge and manure from mink and fox farms. The project may be divided into three main parts. The first part is the chemical composition of the fertiliser with the objective to increase the nitrogen content in sludge-based fertilisers and in compost of mink and fox manure. The second part involves the technique and logistics for forest fertilisation i.e., to develop application equipment that may be integrated in existing forest technical systems. The third part consists of field fertilisation investigations and an environmental impact assessment

  11. Dependence of Soil Respiration on Soil Temperature and Soil Moisture in Successional Forests in Southern China

    Institute of Scientific and Technical Information of China (English)

    Xu-Li Tang; Guo-Yi Zhou; Shu-Guang Liu; De-Qiang Zhang; Shi-Zhong Liu; Jiong Li; Cun-Yu Zhou

    2006-01-01

    The spatial and temporal variations in soil respiration and its relationship with biophysical factors in forests near the Tropic of Cancer remain highly uncertain. To contribute towards an improvement of actual estimates, soil respiration rates, soil temperature, and soil moisture were measured in three successional subtropical forests at the Dinghushan Nature Reserve (DNR) in southern China from March 2003 to February 2005. The overall objective of the present study was to analyze the temporal variations of soil respiration and its biophysical dependence in these forests. The relationships between biophysical factors and soil respiration rates were compared in successional forests to test the hypothesis that these forests responded similarly to biophysical factors. The seasonality of soil respiration coincided with the seasonal climate pattern, with high respiration rates in the hot humid season (April-September) and with low rates in the cool dry season (October-March). Soil respiration measured at these forests showed a clear increasing trend with the progressive succession. Annual mean (± SD) soil respiration rate in the DNR forests was (9.0±4.6) Mg CO2-C/hm2 per year, ranging from (6.1±3.2) Mg CO2-C/hm2 per year in early successional forests to (10.7±4.9) Mg CO2-C/hm2 per year in advanced successional forests. Soil respiration was correlated with both soil temperature and moisture. The T/M model, where the two biophysical variables are driving factors, accounted for 74%-82% of soil respiration variation in DNR forests. Temperature sensitivity decreased along progressive succession stages, suggesting that advanced-successional forests have a good ability to adjust to temperature. In contrast, moisture increased with progressive succession processes. This increase is caused, in part, by abundant respirators in advanced-successional forest, where more soil moisture is needed to maintain their activities.

  12. Dependence of soil respiration on soil temperature and soil moisture in successional forests in Southern China

    Science.gov (United States)

    Tang, X.-L.; Zhou, G.-Y.; Liu, S.-G.; Zhang, D.-Q.; Liu, S.-Z.; Li, Ji; Zhou, C.-Y.

    2006-01-01

    The spatial and temporal variations in soil respiration and its relationship with biophysical factors in forests near the Tropic of Cancer remain highly uncertain. To contribute towards an improvement of actual estimates, soil respiration rates, soil temperature, and soil moisture were measured in three successional subtropical forests at the Dinghushan Nature Reserve (DNR) in southern China from March 2003 to February 2005. The overall objective of the present study was to analyze the temporal variations of soil respiration and its biophysical dependence in these forests. The relationships between biophysical factors and soil respiration rates were compared in successional forests to test the hypothesis that these forests responded similarly to biophysical factors. The seasonality of soil respiration coincided with the seasonal climate pattern, with high respiration rates in the hot humid season (April-September) and with low rates in the cool dry season (October-March). Soil respiration measured at these forests showed a clear increasing trend with the progressive succession. Annual mean (±SD) soil respiration rate in the DNR forests was (9.0 ± 4.6) Mg CO2-C/hm2per year, ranging from (6.1 ± 3.2) Mg CO2-C/hm2per year in early successional forests to (10.7 ± 4.9) Mg CO2-C/hm2 per year in advanced successional forests. Soil respiration was correlated with both soil temperature and moisture. The T/M model, where the two biophysical variables are driving factors, accounted for 74%-82% of soil respiration variation in DNR forests. Temperature sensitivity decreased along progressive succession stages, suggesting that advanced-successional forests have a good ability to adjust to temperature. In contrast, moisture increased with progressive succession processes. This increase is caused, in part, by abundant respirators in advanced-successional forest, where more soil moisture is needed to maintain their activities.

  13. Dynamic of radionuclides behaviour in forest soils

    International Nuclear Information System (INIS)

    Ruehm, W.; Steiner, M.; Wirth, E.; Dvornik, A.; Zhuchenko, T.A.; Kliashtorin, A.; Rafferty, B.; Shaw, G.; Kuchma, N.

    1996-01-01

    Within the research project ECP-5, the dynamics of radionuclides in automorphic forest soils within the 30-km-zone of Chernobyl and of hydromorphic forest soils in Belarus have been investigated. In upland forest soils, the lower layers of the organic horizons are characterized by the highest residence times for radiocesium and represent the largest pool for all radionuclides investigated. According to a preliminary estimate, radiocesium is more mobile compared to 125 Sb, which in turn migrates faster than 60 Co, 144 Ce, and 154 Eu. 106 Ru shows the lowest mobility. With regard to radiocesium, hydromorphic soils exhibit migration rates and transfer factors from soil to trees, which by far exceed those in automorphic soils. Based on a two-component quasi-diffusional model the average bias of 137 Cs in mesotrophic swamp soils was predicted. The activity concentrations of U, Pu, and Cs suggest that U and Pu were originally deposited as hot particles and that U is naturally accumulated in organic horizons

  14. Forests, Trees, and Micronutrient-Rich Food Consumption in Indonesia.

    Science.gov (United States)

    Ickowitz, Amy; Rowland, Dominic; Powell, Bronwen; Salim, Mohammad Agus; Sunderland, Terry

    2016-01-01

    Micronutrient deficiency remains a serious problem in Indonesia with approximately 100 million people, or 40% of the population, suffering from one or more micronutrient deficiencies. In rural areas with poor market access, forests and trees may provide an essential source of nutritious food. This is especially important to understand at a time when forests and other tree-based systems in Indonesia are being lost at unprecedented rates. We use food consumption data from the 2003 Indonesia Demographic Health Survey for children between the ages of one and five years and data on vegetation cover from the Indonesian Ministry of Forestry to examine whether there is a relationship between different tree-dominated land classes and consumption of micronutrient-rich foods across the archipelago. We run our models on the aggregate sample which includes over 3000 observations from 25 provinces across Indonesia as well as on sub-samples from different provinces chosen to represent the different land classes. The results show that different tree-dominated land classes were associated with the dietary quality of people living within them in the provinces where they were dominant. Areas of swidden/agroforestry, natural forest, timber and agricultural tree crop plantations were all associated with more frequent consumption of food groups rich in micronutrients in the areas where these were important land classes. The swidden/agroforestry land class was the landscape associated with more frequent consumption of the largest number of micronutrient rich food groups. Further research needs to be done to establish what the mechanisms are that underlie these associations. Swidden cultivation in is often viewed as a backward practice that is an impediment to food security in Indonesia and destructive of the environment. If further research corroborates that swidden farming actually results in better nutrition than the practices that replace it, Indonesian policy makers may need to

  15. Impacts of invasive earthworms on soil mercury cycling: Two mass balance approaches to an earthworm invasion in a northern Minnesota forest

    Science.gov (United States)

    Sona Psarska; Edward A. Nater; Randy Kolka

    2016-01-01

    Invasive earthworms perturb natural forest ecosystems that initially developed without them, mainly by consuming the forest floor (an organic rich surficial soil horizon) and by mixing the upper parts of the soil. The fate of mercury (Hg) formerly contained in the forest floor is largely unknown. We used two mass balance approaches (simple mass balance and geochemical...

  16. Thermal characteristics and bacterial diversity of forest soil in the Haean basin of Korea.

    Science.gov (United States)

    Kim, Heejung; Lee, Jin-Yong; Lee, Kang-Kun

    2014-01-01

    To predict biotic responses to disturbances in forest environments, it is important to examine both the thermophysical properties of forest soils and the diversity of microorganisms that these soils contain. To predict the effects of climate change on forests, in particular, it is essential to understand the interactions between the soil surface, the air, and the biological diversity in the soil. In this study, the temperature and thermal properties of forest soil at three depths at a site in the Haean basin of Korea were measured over a period of four months. Metagenomic analyses were also carried out to ascertain the diversity of microorganisms inhabiting the soil. The thermal diffusivity of the soil at the study site was 5.9 × 10(-8) m(2) · s(-1). The heat flow through the soil resulted from the cooling and heating processes acting on the surface layers of the soils. The heat productivity in the soil varied through time. The phylum Proteobacteria predominated at all three soil depths, with members of Proteobacteria forming a substantial fraction (25.64 to 39.29%). The diversity and richness of microorganisms in the soil were both highest at the deepest depth, 90 cm, where the soil temperature fluctuation was the minimum.

  17. Thermal Characteristics and Bacterial Diversity of Forest Soil in the Haean Basin of Korea

    Directory of Open Access Journals (Sweden)

    Heejung Kim

    2014-01-01

    Full Text Available To predict biotic responses to disturbances in forest environments, it is important to examine both the thermophysical properties of forest soils and the diversity of microorganisms that these soils contain. To predict the effects of climate change on forests, in particular, it is essential to understand the interactions between the soil surface, the air, and the biological diversity in the soil. In this study, the temperature and thermal properties of forest soil at three depths at a site in the Haean basin of Korea were measured over a period of four months. Metagenomic analyses were also carried out to ascertain the diversity of microorganisms inhabiting the soil. The thermal diffusivity of the soil at the study site was 5.9 × 10−8 m2·s−1. The heat flow through the soil resulted from the cooling and heating processes acting on the surface layers of the soils. The heat productivity in the soil varied through time. The phylum Proteobacteria predominated at all three soil depths, with members of Proteobacteria forming a substantial fraction (25.64 to 39.29%. The diversity and richness of microorganisms in the soil were both highest at the deepest depth, 90 cm, where the soil temperature fluctuation was the minimum.

  18. 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.

  19. 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.

  20. The relationship between species richness and aboveground biomass in a primary Pinus kesiya forest of Yunnan, southwestern China.

    Science.gov (United States)

    Li, Shuaifeng; Lang, Xuedong; Liu, Wande; Ou, Guanglong; Xu, Hui; Su, Jianrong

    2018-01-01

    The relationship between biodiversity and biomass is an essential element of the natural ecosystem functioning. Our research aims at assessing the effects of species richness on the aboveground biomass and the ecological driver of this relationship in a primary Pinus kesiya forest. We sampled 112 plots of the primary P. kesiya forests in Yunnan Province. The general linear model and the structural equation model were used to estimate relative effects of multivariate factors among aboveground biomass, species richness and the other explanatory variables, including climate moisture index, soil nutrient regime and stand age. We found a positive linear regression relationship between the species richness and aboveground biomass using ordinary least squares regressions. The species richness and soil nutrient regime had no direct significant effect on aboveground biomass. However, the climate moisture index and stand age had direct effects on aboveground biomass. The climate moisture index could be a better link to mediate the relationship between species richness and aboveground biomass. The species richness affected aboveground biomass which was mediated by the climate moisture index. Stand age had direct and indirect effects on aboveground biomass through the climate moisture index. Our results revealed that climate moisture index had a positive feedback in the relationship between species richness and aboveground biomass, which played an important role in a link between biodiversity maintenance and ecosystem functioning. Meanwhile, climate moisture index not only affected positively on aboveground biomass, but also indirectly through species richness. The information would be helpful in understanding the biodiversity-aboveground biomass relationship of a primary P. kesiya forest and for forest management.

  1. Reduction of soil erosion on forest roads

    Science.gov (United States)

    Edward R. Burroughs; John G. King

    1989-01-01

    Presents the expected reduction in surface erosion from selected treatments applied to forest road traveledways, cutslopes, fillslopes, and ditches. Estimated erosion reduction is expressed as functions of ground cover, slope gradient, and soil properties whenever possible. A procedure is provided to select rock riprap size for protection of the road ditch.

  2. Sewage Effluent Infiltrates Frozen Forest Soil

    Science.gov (United States)

    Alfred Ray Harris

    1976-01-01

    Secondarily treated sewage effluent, applied at the rate of 1 and 2 inches per week, infiltrated a frozen Sparta sand soil forested with jack pine and scrub oak. Maximum frost depth in treated plots averaged 60 cm and in check plots averages 35 cm. Nitrogen was mobile with some accumulation. Phosphorus was absorbed.

  3. Temporal and Spatial Variation of Soil Bacteria Richness, Composition, and Function in a Neotropical Rainforest.

    Science.gov (United States)

    Kivlin, Stephanie N; Hawkes, Christine V

    2016-01-01

    The high diversity of tree species has traditionally been considered an important controller of belowground processes in tropical rainforests. However, soil water availability and resources are also primary regulators of soil bacteria in many ecosystems. Separating the effects of these biotic and abiotic factors in the tropics is challenging because of their high spatial and temporal heterogeneity. To determine the drivers of tropical soil bacteria, we examined tree species effects using experimental tree monocultures and secondary forests at La Selva Biological Station in Costa Rica. A randomized block design captured spatial variation and we sampled at four dates across two years to assess temporal variation. We measured bacteria richness, phylogenetic diversity, community composition, biomass, and functional potential. All bacteria parameters varied significantly across dates. In addition, bacteria richness and phylogenetic diversity were affected by the interaction of vegetation type and date, whereas bacteria community composition was affected by the interaction of vegetation type and block. Shifts in bacteria community richness and composition were unrelated to shifts in enzyme function, suggesting physiological overlap among taxa. Based on the observed temporal and spatial heterogeneity, our understanding of tropical soil bacteria will benefit from additional work to determine the optimal temporal and spatial scales for sampling. Understanding spatial and temporal variation will facilitate prediction of how tropical soil microbes will respond to future environmental change.

  4. Abiotic and Biotic Soil Characteristics in Old Growth Forests and Thinned or Unthinned Mature Stands in Three Regions of Oregon

    Directory of Open Access Journals (Sweden)

    David A. Perry

    2012-09-01

    Full Text Available We compared forest floor depth, soil organic matter, soil moisture, anaerobic mineralizable nitrogen (a measure of microbial biomass, denitrification potential, and soil/litter arthropod communities among old growth, unthinned mature stands, and thinned mature stands at nine sites (each with all three stand types distributed among three regions of Oregon. Mineral soil measurements were restricted to the top 10 cm. Data were analyzed with both multivariate and univariate analyses of variance. Multivariate analyses were conducted with and without soil mesofauna or forest floor mesofauna, as data for those taxa were not collected on some sites. In multivariate analysis with soil mesofauna, the model giving the strongest separation among stand types (P = 0.019 included abundance and richness of soil mesofauna and anaerobic mineralizable nitrogen. The best model with forest floor mesofauna (P = 0.010 included anaerobic mineralizable nitrogen, soil moisture content, and richness of forest floor mesofauna. Old growth had the highest mean values for all variables, and in both models differed significantly from mature stands, while the latter did not differ. Old growth also averaged higher percent soil organic matter, and analysis including that variable was significant but not as strong as without it. Results of the multivariate analyses were mostly supported by univariate analyses, but there were some differences. In univariate analysis, the difference in percent soil organic matter between old growth and thinned mature was due to a single site in which the old growth had exceptionally high soil organic matter; without that site, percent soil organic matter did not differ between old growth and thinned mature, and a multivariate model containing soil organic matter was not statistically significant. In univariate analyses soil mesofauna had to be compared nonparametrically (because of heavy left-tails and differed only in the Siskiyou Mountains, where

  5. Plant species richness regulates soil respiration through changes in productivity.

    NARCIS (Netherlands)

    Tavares Correa Dias, A.; van Ruijven, J.; Berendse, F.

    2010-01-01

    Soil respiration is an important pathway of the C cycle. However, it is still poorly understood how changes in plant community diversity can affect this ecosystem process. Here we used a long-term experiment consisting of a gradient of grassland plant species richness to test for effects of

  6. Plant species richness regulates soil respiration through changes in productivity

    NARCIS (Netherlands)

    Dias, A.A.; Ruijven, van J.; Berendse, F.

    2010-01-01

    Soil respiration is an important pathway of the C cycle. However, it is still poorly understood how changes in plant community diversity can affect this ecosystem process. Here we used a long-term experiment consisting of a gradient of grassland plant species richness to test for effects of

  7. Soil Effects on Forest Structure and Diversity in a Moist and a Dry Tropical Forest

    NARCIS (Netherlands)

    Peña-Claros, M.; Poorter, L.; Alarcon, A.; Blate, G.; Choque, U.; Fredericksen, T.S.; Justiniano, J.; Leaño, C.; Licona, J.C.; Pariona, W.; Putz, F.E.; Quevedo, L.; Toledo, M.

    2012-01-01

    Soil characteristics are important drivers of variation in wet tropical forest structure and diversity, but few studies have evaluated these relationships in drier forest types. Using tree and soil data from 48 and 32 1 ha plots, respectively, in a Bolivian moist and dry forest, we asked how soil

  8. Soil Taxonomy and land evaluation for forest establishment

    Science.gov (United States)

    Haruyoshi Ikawa

    1992-01-01

    Soil Taxonomy, the United States system of soil classification, can be used for land evaluation for selected purposes. One use is forest establishment in the tropics, and the soil family category is especially functional for this purpose. The soil family is a bionomial name with descriptions usually of soil texture, mineralogy, and soil temperature classes. If the...

  9. Changes in faunal and vegetation communities along a soil calcium gradient in northern hardwood forests

    Science.gov (United States)

    Beier, Colin M.; Woods, Anne M.; Hotopp, Kenneth P.; Gibbs, James P.; Mitchell, Myron J.; Dovciak, Martin; Leopold, Donald J.; Lawrence, Gregory B.; Page, Blair D.

    2012-01-01

    Depletion of Ca from forest soils due to acidic deposition has had potentially pervasive effects on forest communities, but these impacts remain largely unknown. Because snails, salamanders, and plants play essential roles in the Ca cycle of northern hardwood forests, we hypothesized that their community diversity, abundance, and structure would vary with differences in biotic Ca availability. To test this hypothesis, we sampled 12 upland hardwood forests representing a soil Ca gradient in the Adirondack Mountains, New York (USA), where chronic deposition has resulted in acidified soils but where areas of well-buffered soils remain Ca rich due to parent materials. Along the gradient of increasing soil [Ca2+], we observed increasing trends in snail community richness and abundance, live biomass of redback salamanders (Plethodon cinereus (Green, 1818)), and canopy tree basal area. Salamander communities were dominated by mountain dusky salamanders (Desmognathus ochrophaeus Cope, 1859) at Ca-poor sites and changed continuously along the Ca gradient to become dominated by redback salamanders at the Ca-rich sites. Several known calciphilic species of snails and plants were found only at the highest-Ca sites. Our results indicated that Ca availability, which is shaped by geology and acidic deposition inputs, influences northern hardwood forest ecosystems at multiple trophic levels, although the underlying mechanisms require further study.

  10. Fate of nitrogenous fertilizers in forest soil

    International Nuclear Information System (INIS)

    Pang, P.C.K.

    1984-01-01

    The fate of the nitrogenous fertilizers through the processes of denitrification, ammonia volatilization, immobilization and uptake by a conifer is determined, with the aid of 15 N-labelled fertizers. The foliage of Douglas-fir was able to absorb gaseous ammonia under optimal conditions. Denitrification and immobilization of fertilizer-N by forest soil were highest with forest floor samples and decreased with depth. Laboratory studies with four-year-old Douglas-fir demostrated that a higher quantity of fertilizer-N was utilized by trees when the nitrogen was supplied as NO 3 - rather than NH 4 + . (M.A.C.) [pt

  11. VARIABILITY OF ARABLE AND FOREST SOILS PROPERTIES ON ERODED SLOPES

    Directory of Open Access Journals (Sweden)

    Paweł Wiśniewski

    2014-10-01

    Full Text Available The basic method of reducing soil and land erosion is a change of land use, for example, from arable to forest. Particularly effective as a protective role – according to the Polish law – soil-protecting forests. The thesis presents differences in the deformation of the basic soil properties on moraine slopes, depending on land use. There has been presented the function and the efficiency of the soil-protecting forests in erosion control. The soil cross section transects and soil analysis displayed that soil-protecting forests are making an essential soil cover protection from degradation, inter alia, limiting the decrease of humus content, reduction of upper soil horizons and soil pedons layer. On the afforested slopes it was stated some clear changes of grain size and chemical properties of soils in relation to adjacent slopes agriculturally used.

  12. Modelling root reinforcement in shallow forest soils

    Science.gov (United States)

    Skaugset, Arne E.

    1997-01-01

    A hypothesis used to explain the relationship between timber harvesting and landslides is that tree roots add mechanical support to soil, thus increasing soil strength. Upon harvest, the tree roots decay which reduces soil strength and increases the risk of management -induced landslides. The technical literature does not adequately support this hypothesis. Soil strength values attributed to root reinforcement that are in the technical literature are such that forested sites can't fail and all high risk, harvested sites must fail. Both unstable forested sites and stable harvested sites exist, in abundance, in the real world thus, the literature does not adequately describe the real world. An analytical model was developed to calculate soil strength increase due to root reinforcement. Conceptually, the model is composed of a reinforcing element with high tensile strength, i.e. a conifer root, embedded in a material with little tensile strength, i.e. a soil. As the soil fails and deforms, the reinforcing element also deforms and stretches. The lateral deformation of the reinforcing element is treated analytically as a laterally loaded pile in a flexible foundation and the axial deformation is treated as an axially loaded pile. The governing differential equations are solved using finite-difference approximation techniques. The root reinforcement model was tested by comparing the final shape of steel and aluminum rods, parachute cord, wooden dowels, and pine roots in direct shear with predicted shapes from the output of the root reinforcement model. The comparisons were generally satisfactory, were best for parachute cord and wooden dowels, and were poorest for steel and aluminum rods. A parameter study was performed on the root reinforcement model which showed reinforced soil strength increased with increasing root diameter and soil depth. Output from the root reinforcement model showed a strain incompatibility between large and small diameter roots. The peak

  13. Local climatic conditions constrain soil yeast diversity patterns in Mediterranean forests, woodlands and scrub biome.

    Science.gov (United States)

    Yurkov, Andrey M; Röhl, Oliver; Pontes, Ana; Carvalho, Cláudia; Maldonado, Cristina; Sampaio, José Paulo

    2016-02-01

    Soil yeasts represent a poorly known fraction of the soil microbiome due to limited ecological surveys. Here, we provide the first comprehensive inventory of cultivable soil yeasts in a Mediterranean ecosystem, which is the leading biodiversity hotspot for vascular plants and vertebrates in Europe. We isolated and identified soil yeasts from forested sites of Serra da Arrábida Natural Park (Portugal), representing the Mediterranean forests, woodlands and scrub biome. Both cultivation experiments and the subsequent species richness estimations suggest the highest species richness values reported to date, resulting in a total of 57 and 80 yeast taxa, respectively. These values far exceed those reported for other forest soils in Europe. Furthermore, we assessed the response of yeast diversity to microclimatic environmental factors in biotopes composed of the same plant species but showing a gradual change from humid broadleaf forests to dry maquis. We observed that forest properties constrained by precipitation level had strong impact on yeast diversity and on community structure and lower precipitation resulted in an increased number of rare species and decreased evenness values. In conclusion, the structure of soil yeast communities mirrors the environmental factors that affect aboveground phytocenoses, aboveground biomass and plant projective cover. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  14. Linkages between forest soils and water quality and quantity

    Science.gov (United States)

    Daniel G. Neary; George G. Ice; C. Rhett Jackson

    2009-01-01

    The most sustainable and best quality fresh water sources in the world originate in forest ecosystems. The biological, chemical, and physical characteristics of forest soils are particularly well suited to delivering high quality water to streams, moderating stream hydrology, and providing diverse aquatic habitat. Forest soils feature litter layers and...

  15. [Species composition and diversity of soil mesofauna in the 'Holy Hills' fragmentary tropical rain forest of Xishuangbanna, China].

    Science.gov (United States)

    Yang, X; Sha, L

    2001-04-01

    The species composition and diversity of soil mesofauna were examined in fragmented dry tropical seasonal rainforest of tow 'Holy Hills' of Dai nationality, compared with the continuous moist tropical seasonal rain forest of Nature Reserve in Xishuangbanna area. 5 sample quadrats were selected along the diagonal of 20 m x 20 m sampling plot, and the samples of litterfall and 0-3 cm soil were collected from each 50 cm x 10 cm sample quadrat. Animals in soil sample were collected by using dry-funnel(Tullgren's), were identified to their groups according to the order. The H' index, D.G index and the pattern of relative abundance of species were used to compare the diversity of soil mesofauna. The results showed that the disturbance of vegetation and soil resulted by tropical rainforest fragmentation was the major factor affecting the diversity of soil mesofauna. Because the fragmented forest was intruded by some pioneer tree species and the "dry and warm" effect operated, this forest had more litterfall on the floor and more humus in the soil than the continuous moist rain forest. The soil condition with more soil organic matter, total N and P, higher pH value and lower soil bulk density became more favorable to the soil mesofauna. Therefore, the species richness, abundance and diversity of soil mesofauna in fragmented forests were higher than those in continuous forest, but the similarity of species composition in fragmented forest to the continuous forest was minimal. Soil mesofauna diversity in fragmented forests did not change with decreasing fragmented area, indicating that there was no species-area effect operation in this forest. The pattern of relative abundance of species in these forest soils was logarithmic series distribution.

  16. Overcoming of Soil Contamination with Pesticides in Forest Nurseries Using the Activity of Microorganisms

    Directory of Open Access Journals (Sweden)

    Irina A. Freiberg

    2010-01-01

    Full Text Available The use of pesticides during cultivation of pine seedlings in forest nurseries resultsin the formation two phenotypes of teratomorph seedlings – conditionally normal andabnormal. Growing forest cultures from teratomorph seedlings leads to their low survivalrate. It is known that pesticides and their metabolic products can remain in soil for manyyears. It is therefore impossible to rely only on natural degradation of pesticides in soil. Apromising way of removing pesticides from soil is their microbiological decomposition.This method is preferable because there is a meliorative organic substance not far from forestnurseries – i.e. forest litter rich in microorganisms. The purpose of these experimentswas to examine the influence of forest litter applied on pesticide decomposition in soil andmorphology of pine seedlings. The rates of forest litter that were most effective in decompositionof pesticides and the activity of microbial communities in litter, depending on foreststand structure, were determined. Estimation of that action was based on the morphologyof seedlings (rate of pine seedlings with normal, conditionally normal and abnormalphenotypes, intensity of CO2 emission from soil and catalase activity, which correlates withthe number of soil microorganisms. The results of these experiments showed the mosteffective activity of forest litter at the application rate of 20 kg/m2. The number of seedlingswith normal phenotype rose from 32% up to 40%. Besides, it was noted that saprophyteswere most effective in pine forest litter, which is characterized by a more acid reaction ofsoil solution, while most others were rich in fungi. The highest number of normal phenotypeseedlings, intensity of CO2 emission and activity of soil catalase were correlated withthe microbiological activity of the applied pine forest litter.

  17. Influence of environmental factors on the spatial distribution and diversity of forest soil in Latvia

    Directory of Open Access Journals (Sweden)

    Raimonds Kasparinskis

    2012-02-01

    Full Text Available This study was carried out to determine the spatial relationships between environmental factors (Quaternary deposits, topographical situation, land cover, forest site types, tree species, soil texture and soil groups, and their prefix qualifiers (according to the international Food and Agricultural Organization soil classification system World Reference Base for Soil Resources [FAO WRB]. The results show that it is possible to establish relationships between the distribution of environmental factors and soil groups by applying the generalized linear models in data statistical analysis, using the R 2.11.1 software for processing data from 113 sampling plots throughout the forest territory of Latvia.A very high diversity of soil groups in a relatively similar geological structure was revealed. For various reasons there is not always close relationship between the soil group, their prefix qualifiers and Quaternary deposits, as well as between forest site types, the dominant tree species and specific soil group and its prefix qualifiers. Close correlation was established between Quaternary deposits, forest site types, dominant tree species and soil groups within nutrient-poor sediments and very rich deposits containing free carbonates. No significant relationship was detected between the CORINE Land Cover 2005 classes, topographical situation and soil group.

  18. Effect of soil compaction and biomass removal on soil CO2 efflux in a Missouri forest

    Science.gov (United States)

    Felix, Jr. Ponder

    2005-01-01

    Forest disturbances associated with harvesting activities can affect soil properties and soil respiration. A soda-lime technique was used to measure soil carbon dioxide (CO2) efflux rates in clearcut plots of a Missouri oak-hickory (Quercus spp. L.-Carya spp. Nutt.) forest 4 years after being treated with two levels of forest...

  19. Species and genera of soil nematodes in forest ecosystems of the Vihorlat Protected Landscape Area, Slovakia

    Czech Academy of Sciences Publication Activity Database

    Háněl, Ladislav; Čerevková, A.

    2010-01-01

    Roč. 47, č. 2 (2010), s. 123-135 ISSN 0440-6605 Grant - others:Slovak Academy of Sciences(SK) 2/7191/27 Institutional research plan: CEZ:AV0Z60660521 Keywords : forest * soil nematodes * species richness Subject RIV: EH - Ecology, Behaviour Impact factor: 0.847, year: 2010

  20. Changes in microbial community characteristics and soil organic matter with nitrogen additions in two tropical forests

    Science.gov (United States)

    Daniela F. Cusack; Whendee L. Silver; Margaret S. Torn; Sarah D. Burton; Mary K. Firestone

    2011-01-01

    Microbial communities and their associated enzyme activities affect the amount and chemical quality of carbon (C) in soils. Increasing nitrogen (N) deposition, particularly in N-rich tropical forests, is likely to change the composition and behavior of microbial communities and feed back on ecosystem structure and function. This study presents a novel assessment of...

  1. Micromorphological characteristics of sandy forest soils recently impacted by wildfires in Russia

    Science.gov (United States)

    Maksimova, Ekaterina; Abakumov, Evgeny

    2017-04-01

    Two fire-affected soils were studied using micromorphological methods. The objective of the paper is to assess and compare fire effects on the micropedological organisation of soils in a forest-steppe zone of central Russia (Volga Basin, Togliatti city). Samples were collected in the green zone of Togliatti city. The results showed that both soils were rich in quartz and feldspar. Mica was highly present in soils affected by surface fires, while calcium carbonates were identified in the soils affected by crown fires. The type of plasma is humus-clay, but the soil assemblage is plasma-silt with a prevalence of silt. Angular and subangular grains are the most dominant soil particulates. No evidence of intensive weathering was detected. There was a decrease in the porosity of soils affected by fires as a consequence of soil pores filled with ash and charcoal.

  2. Soil heat flux measurements in an open forest

    NARCIS (Netherlands)

    vanderMeulen, MJW; Klaassen, W; Kiely, G

    1996-01-01

    The soil surface heat flux in an open oak forest was determined at four locations to account for the heterogeneity of the forest. Soil temperatures and soil water content were measured at several depths and an integration method with three layers was used. The thickness of the bottom layer was

  3. Soil Heat Flux Measurements in an Open Forest

    NARCIS (Netherlands)

    Meulen, M.W.J. van der; Klaassen, W.

    1996-01-01

    The soil surface heat flux in an open oak forest was determined at four locations to account for the heterogeneity of the forest. Soil temperatures and soil water content were measured at several depths and an integration method with three layers was used. The thickness of the bottom layer was

  4. Long-Term Soil Chemistry Changes in Aggrading Forest Ecosystems

    Science.gov (United States)

    Jennifer D. Knoepp; Wayne T. Swank

    1994-01-01

    Assessing potential long-term forest productivity requires identification of the processes regulating chemical changes in forest soils. We resampled the litter layer and upper two mineral soil horizons, A and AB/BA, in two aggrading southern Appalachian watersheds 20 yr after an earlier sampling. Soils from a mixed-hardwood watershed exhibited a small but significant...

  5. Using soil quality indicators for monitoring sustainable forest management

    Science.gov (United States)

    James A. Burger; Garland Gray; D. Andrew Scott

    2010-01-01

    Most private and public forest land owners and managers are compelled to manage their forests sustainably, which means management that is economically viable,environmentally sound, and socially acceptable. To meet this mandate, the USDA Forest Service protects the productivity of our nation’s forest soils by monitoring and evaluating management activities to ensure...

  6. Soil amendments effects on radiocesium translocation in forest soils.

    Science.gov (United States)

    Sugiura, Yuki; Ozawa, Hajime; Umemura, Mitsutoshi; Takenaka, Chisato

    2016-12-01

    We conducted an experiment to investigate the potential of phytoremediation by soil amendments in a forest area. To desorb radiocesium ( 137 Cs) from variable charges in the soil, ammonium sulfate (NH 4 + ) and elemental sulfur (S) (which decrease soil pH) were applied to forest soil collected from contaminated area at a rate of 40 and 80 g/m 2 , respectively. A control condition with no soil treatment was also considered. We defined four groups of aboveground conditions: planted with Quercus serrata, planted with Houttuynia cordata, covered with rice straw as litter, and unplanted/uncovered (control). Cultivation was performed in a greenhouse with a regular water supply for four months. Following elemental sulfur treatment, soil pH values were significantly lower than pH values following ammonium sulfate treatment and no treatment. During cultivation, several plant species germinated from natural seeds. No clear differences in aboveground tissue 137 Cs concentrations in planted Q. serrata and H. cordata were observed among the treatments. However, aboveground tissue 137 Cs concentration values in the germinated plants following elemental sulfur treatment were higher than the values following the ammonium sulfate treatment and no treatment. Although biomass values for Q. serrata, H. cordata, and germinated plants following elemental sulfur treatment tended to be low, the total 137 Cs activities in the aboveground tissue of germinated plants were higher than those following ammonium sulfate treatment and no treatment in rice straw and unplanted conditions. Although no significant differences were observed, 137 Cs concentrations in rice straw following ammonium sulfate and elemental sulfur treatments tended to be higher than those in the control case. The results of this study indicate that elemental sulfur lowers the soil pH for a relatively long period and facilitates 137 Cs translocation to newly emerged and settled plants or litter, but affects plant growth in

  7. Soils characterisation along ecological forest zones in the Eastern Himalayas

    Science.gov (United States)

    Simon, Alois; Dhendup, Kuenzang; Bahadur Rai, Prem; Gratzer, Georg

    2017-04-01

    Elevational gradients are commonly used to characterise vegetation patterns and, to a lesser extent, also to describe soil development. Furthermore, interactions between vegetation cover and soil characteristics are repeatedly observed. Combining information on soil development and easily to distinguish forest zones along elevational gradients, creates an added value for forest management decisions especially in less studied mountain regions. For this purpose, soil profiles along elevational gradients in the temperate conifer forests of Western and Central Bhutan, ranging from 2600-4000m asl were investigated. Thereby, 82 soil profiles were recorded and classified according to the World Reference Base for Soil Resources. Based on 19 representative profiles, genetic horizons were sampled and analysed. We aim to provide fundamental information on forest soil characteristics along these elevational transects. The results are presented with regard to ecological forest zones. The elevational distribution of the reference soil groups showed distinct distribution ranges for most of the soils. Cambisols were the most frequently recorded reference soil group with 58% of the sampled profiles, followed by Podzols in higher elevations, and Stagnosols, at intermediate elevations. Fluvisols occurred only at the lower end of the elevational transects and Phaeozems only at drier site conditions in the cool conifer dry forest zone. The humus layer thickness differs between forest zones and show a shift towards increased organic layer (O-layer) with increasing elevation. The reduced biomass productivity with increasing elevation and subsequently lower litter input compensates for the slow decomposition rates. The increasing O-layer thickness is an indicator of restrained intermixing of organic and mineral components by soil organisms at higher elevation. Overall, the soil types and soil characteristics along the elevational gradient showed a continuous and consistent change, instead

  8. Soil carbon storage estimation in a forested watershed using quantitative soil-landscape modeling

    Science.gov (United States)

    James A. Thompson; Randall K. Kolka

    2005-01-01

    Carbon storage in soils is important to forest ecosystems. Moreover, forest soils may serve as important C sinks for ameliorating excess atmospheric CO2. Spatial estimates of soil organic C (SOC) storage have traditionally relied upon soil survey maps and laboratory characterization data. This approach does not account for inherent variability...

  9. Benchmark values for forest soil carbon stocks in Europe

    DEFF Research Database (Denmark)

    De Vos, Bruno; Cools, Nathalie; Ilvesniemi, Hannu

    2015-01-01

    Soil organic carbon (SOC) stocks in forest floors and in mineral and peat forest soils were estimated at the European scale. The assessment was based on measured C concentration, bulk density, coarse fragments and effective soil depth data originating from 4914 plots in 22 EU countries belonging...... to the UN/ECE ICP Forests 16 × 16 km Level I network. Plots were sampled and analysed according to harmonized methods during the 2nd European Forest Soil Condition Survey. Using continuous carbon density depth functions, we estimated SOC stocks to 30-cm and 1-m depth, and stratified these stocks according...... to 22 WRB Reference Soil Groups (RSGs) and 8 humus forms to provide European scale benchmark values. Average SOC stocks amounted to 22.1 t C ha− 1 in forest floors, 108 t C ha− 1 in mineral soils and 578 t C ha− 1 in peat soils, to 1 m depth. Relative to 1-m stocks, the vertical SOC distribution...

  10. Forest soil carbon is threatened by intensive biomass harvesting.

    Science.gov (United States)

    Achat, David L; Fortin, Mathieu; Landmann, Guy; Ringeval, Bruno; Augusto, Laurent

    2015-11-04

    Forests play a key role in the carbon cycle as they store huge quantities of organic carbon, most of which is stored in soils, with a smaller part being held in vegetation. While the carbon storage capacity of forests is influenced by forestry, the long-term impacts of forest managers' decisions on soil organic carbon (SOC) remain unclear. Using a meta-analysis approach, we showed that conventional biomass harvests preserved the SOC of forests, unlike intensive harvests where logging residues were harvested to produce fuelwood. Conventional harvests caused a decrease in carbon storage in the forest floor, but when the whole soil profile was taken into account, we found that this loss in the forest floor was compensated by an accumulation of SOC in deeper soil layers. Conversely, we found that intensive harvests led to SOC losses in all layers of forest soils. We assessed the potential impact of intensive harvests on the carbon budget, focusing on managed European forests. Estimated carbon losses from forest soils suggested that intensive biomass harvests could constitute an important source of carbon transfer from forests to the atmosphere (142-497 Tg-C), partly neutralizing the role of a carbon sink played by forest soils.

  11. UNDERSTANDING AND APPLICABILITY OF THE FOREST SOIL CONCEPT

    Directory of Open Access Journals (Sweden)

    Ana Paula Moreira Rovedder

    2013-08-01

    Full Text Available http://dx.doi.org/10.5902/1980509810563The forestry sector plays an important role in the socioeconomic and environmental Brazilian context, therefore the improvement of the knowledge about forest soil becomes essential for its sustainable use as a conservation base of natural heritage as resource for economical development. Forest soil can be characterized by pedogenesis occurred under influence of a forestry typology or under a currently natural or cultivated forest coverage. Differentiating forest soils from those occupied with other uses helps the understanding of possible alterations related to vegetal coverage and the developing of better management strategies to soil and forest use. Nevertheless, there is no consensus about this term because the soils present variations according to the forest characteristics, stimulating the discussion concerning its interpretation and applicability. This review aimed to analyze the utilization of forest soil concept, highlighting the differentiation characteristics and the relation with coverage type, natural or cultivated. Aspects related to deposition, quality and management of residues, nutrients cycling, soil compaction and site productivity are emphasized. The forest soil concept is widely used by specific literature and useful to collect specific information and to plan the sustainable use of soil and forest. The improvement of knowledge about these resources provides the creation of a common identity, supporting comparative studies and consolidating the research regarding to this theme.

  12. Acid-base status and changes in Swedish forest soils

    International Nuclear Information System (INIS)

    Karltun, Erik; Stendahl, Johan; Lundin, Lars

    2003-01-01

    In this paper we use data from the Swedish National Survey of Forest Soils and Vegetation (NSFSV) to evaluate the present acid-base status of forest soils to try to answer the following questions. Which role do anthropogenic and biological acidification play for the present acid-base status of the soil profile? What is the present acid-base status of Swedish forest soils and how large areas may be considered as severely acidified? Do the current tendencies in soil acid-base status correspond with the positive development in surface waters?

  13. Sorption of niobium on boreal forest soil

    Energy Technology Data Exchange (ETDEWEB)

    Soederlund, Mervi; Hakanen, Martti; Lehto, Jukka [Helsinki Univ. (Finland). Lab. of Radiochemistry

    2015-07-01

    The sorption of niobium (Nb) was investigated on humus and mineral soil samples taken from various depths of a four-metre deep forest soil pit on Olkiluoto Island, southwestern Finland. Mass distribution coefficients, K{sub d}, were determined in batch sorption tests. The steady state of Nb sorption was observed in the mineral soil samples already after one week of equilibration, and sorption decreased with depth from a very high value of 185000 mL/g at 0.7 m to 54000 mL/g at 3.4 m. The reason behind this decrease is probably the tenfold reduction in the specific surface area of the soil at the same depth range. Distribution coefficients were clearly lower in the humus layer (1000 mL/g). The K{sub d} values determined in pure water at a pH range of 4.7-6.5 were at a high level (above 55000 mL/g), but decreased dramatically above pH 6.5, corresponding to the change in the major Nb species from the neutral Nb(OH){sub 5} to the low-sorbing anionic Nb(OH){sub 6}{sup -} and Nb(OH){sub 7}{sup 2-}. However, the K{sub d} values in the model soil solution were in the slightly alkaline range an order of magnitude higher than in pure water, which is probably caused by the formation of calcium niobate surface precipitate or electrostatic interaction between surface-sorbed calcium and solute Nb. Among nine soil constituent minerals kaolinite performed best in retaining Nb in both pure water and model soil solution at pH 8, whereas potassium feldspar showed the poorest sorption. The K{sub d} value for kaolinite was above 500000 mL/g in both solutions, while the respective potassium feldspar values were in the range of 120-220 mL/g.

  14. Forest soil biology-timber harvesting relationships: a perspective

    Science.gov (United States)

    M. F. Jurgensen; M. J. Larsen; A. E. Harvey

    1979-01-01

    Timber harvesting has a pronounced effect on the soil microflora by wood removal and changing properties. This paper gives a perspective on soil biology-harvesting relationships with emphasis on the northern Rocky Mountain region. Of special significance to forest management operations are the effects of soil micro-organisms on: the availability of soil nutrients,...

  15. Isotope geochemistry of sulfur in forest soils and in new groundwater below forest soils

    International Nuclear Information System (INIS)

    Mayer, B.

    1993-04-01

    The isotope geochemistry of sulphur in aerobic forest soils and new groundwater below forest soils was investigated for the purpose of investigating the transport and transformation behaviour of sulfate in the water-unsaturated zone. The effects of hydrodynamic and biogeochemical processes on the development of seepage water sulfate isotopes between depositions and groundwater were investigated by means of laboratory experiments, profile studies, lysimeter experiments, and field studies in order to determine the sulphur conversion processes. Dissolved sulphur from precipitates, seepage water, creek water and groundwater, as well as sulphur extracted from soil samples, were precipitated in the form of BaSO 4 or AgS 2 , decomposed thermally into SO 2 or CO 2 , and the 34 S/ 32 S and 18 O/ 16 O isotope ratios were determined by mass spectrometry. (orig.) [de

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

    Directory of Open Access Journals (Sweden)

    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.

  17. Modeling soil erosion and transport on forest landscape

    Science.gov (United States)

    Ge Sun; Steven G McNulty

    1998-01-01

    Century-long studies on the impacts of forest management in North America suggest sediment can cause major reduction on stream water quality. Soil erosion patterns in forest watersheds are patchy and heterogeneous. Therefore, patterns of soil erosion are difficult to model and predict. The objective of this study is to develop a user friendly management tool for land...

  18. Acidification and Nitrogen Eutrophication of Austrian Forest Soils

    Directory of Open Access Journals (Sweden)

    Robert Jandl

    2012-01-01

    Full Text Available We evaluated the effect of acidic deposition and nitrogen on Austrian forests soils. Until thirty years ago air pollution had led to soil acidification, and concerns on the future productivity of forests were raised. Elevated rates of nitrogen deposition were believed to cause nitrate leaching and imbalanced forest nutrition. We used data from a soil monitoring network to evaluate the trends and current status of the pH and the C : N ratio of Austrian forest soils. Deposition measurements and nitrogen contents of Norway spruce needles and mosses were used to assess the nitrogen supply. The pH values of soils have increased because of decreasing proton depositions caused by reduction of emissions. The C : N ratio of Austrian forest soils is widening. Despite high nitrogen deposition rates the increase in forest stand density and productivity has increased the nitrogen demand. The Austrian Bioindicator Grid shows that forest ecosystems are still deficient in nitrogen. Soils retain nitrogen efficiently, and nitrate leaching into the groundwater is presently not a large-scale problem. The decline of soil acidity and the deposition of nitrogen together with climate change effects will further increase the productivity of the forests until a limiting factor such as water scarcity becomes effective.

  19. Water repellency of two forest soils after biochar addition

    Science.gov (United States)

    D. S. Page-Dumroese; P. R. Robichaud; R. E. Brown; J. M. Tirocke

    2015-01-01

    Practical application of black carbon (biochar) to improve forest soil may be limited because biochar is hydrophobic. In a laboratory, we tested the water repellency of biochar application (mixed or surface applied) to two forest soils of varying texture (a granitic coarse-textured Inceptisol and an ash cap fine-textured Andisol) at four different application rates (0...

  20. Soil Organic Carbon Responses to Forest Expansion on Mountain Grasslands

    DEFF Research Database (Denmark)

    Guidi, Claudia

    . Changes in labile soil C were assessed by carbohydrate and thermal analyses of soil samples and fractions. Forest expansion on mountain grasslands caused a decrease in SOC stocks within the mineral soil. The SOC accumulation within the organic layers following forest establishment could not fully...... and thermally labile to resistant components decreased from grassland to forest successional stages, and corresponded to decreased SOC protection within stable aggregates. This PhD thesis showed that mineral SOC stocks and physically protected SOC fractions decreased following forest expansion on mountain......Grassland abandonment followed by progressive forest expansion is the dominant land-use change in the European Alps. Contrasting trends in soil organic carbon (SOC) stocks have been reported for mountainous regions following forest expansion on grasslands. Moreover, its effects on SOC properties...

  1. The relation between forest structure and soil burn severity

    Science.gov (United States)

    Theresa B. Jain; Russell T. Graham; David S. Pilliod

    2006-01-01

    A study funded through National Fire Plan evaluates the relation between pre-wildfire forest structure and post-wildfire soil burn severity across three forest types: dry, moist, and cold forests. Over 73 wildfires were sampled in Idaho, Oregon, Montana, Colorado, and Utah, which burned between 2000 and 2003. Because of the study’s breadth, the results are applicable...

  2. Nematodes inhabit soils of forest and clear-cut areas

    Science.gov (United States)

    Alex L. Shigo; George Yelenosky

    1960-01-01

    Nematodes are present in all forest soils, but their effects on forest trees are not known. The known destructive nature of these worms on other woody crops suggests that they may also be involved in causing some of the unexplainable losses in vigor and mortality of forest trees.

  3. Mapping Soil Properties of Africa at 250 m Resolution: Random Forests Significantly Improve Current Predictions.

    Directory of Open Access Journals (Sweden)

    Tomislav Hengl

    Full Text Available 80% of arable land in Africa has low soil fertility and suffers from physical soil problems. Additionally, significant amounts of nutrients are lost every year due to unsustainable soil management practices. This is partially the result of insufficient use of soil management knowledge. To help bridge the soil information gap in Africa, the Africa Soil Information Service (AfSIS project was established in 2008. Over the period 2008-2014, the AfSIS project compiled two point data sets: the Africa Soil Profiles (legacy database and the AfSIS Sentinel Site database. These data sets contain over 28 thousand sampling locations and represent the most comprehensive soil sample data sets of the African continent to date. Utilizing these point data sets in combination with a large number of covariates, we have generated a series of spatial predictions of soil properties relevant to the agricultural management--organic carbon, pH, sand, silt and clay fractions, bulk density, cation-exchange capacity, total nitrogen, exchangeable acidity, Al content and exchangeable bases (Ca, K, Mg, Na. We specifically investigate differences between two predictive approaches: random forests and linear regression. Results of 5-fold cross-validation demonstrate that the random forests algorithm consistently outperforms the linear regression algorithm, with average decreases of 15-75% in Root Mean Squared Error (RMSE across soil properties and depths. Fitting and running random forests models takes an order of magnitude more time and the modelling success is sensitive to artifacts in the input data, but as long as quality-controlled point data are provided, an increase in soil mapping accuracy can be expected. Results also indicate that globally predicted soil classes (USDA Soil Taxonomy, especially Alfisols and Mollisols help improve continental scale soil property mapping, and are among the most important predictors. This indicates a promising potential for transferring

  4. Modelling trends in soil solution concentrations under five forest-soil combinations in the Netherlands

    NARCIS (Netherlands)

    Salm, van der C.; Vries, de W.; Kros, J.

    1996-01-01

    The influence of forest and soil properties on changes in soil solution concentration upon a reduction deposition was examined for five forest-soil combinations with the dynamic RESAM model. Predicted concentrations decreased in the direction Douglas fir - Scotch pine - oak, due to decreased

  5. Granulated wood ash to forest soil - Ecological effects

    International Nuclear Information System (INIS)

    Rosen, K.; Eriksson, H.; Clarholm, M.; Lundkvist, H.; Rudebeck, A.

    1993-01-01

    This report describes research concerning ecological effects of wood ash recycling to forest soils. The main part of the minerals in the wood fuels are retained in the ashes after combustion. By returning the ashes back to the cleared forest areas, the mineral losses can be reduced. Adding ashes and limestone is a method to vitalize acidified forest soils and restore the production capacity. 48 refs, 26 figs, 8 tabs

  6. SOIL QUALITY CHANGES FOLLOWING FOREST CLEARANCE IN BENGKULU, SUMATRA

    Directory of Open Access Journals (Sweden)

    I.P. HANDAYANI

    2004-01-01

    Full Text Available Intense destruction and degradation of tropical forests is recognized as one of the environmental threats and tragedies. These have increased the need to assess the effects of subsequent land-use following forest extraction on soil quality. Therefore, the objective of this study is to evaluate the impacts of land-use type on soil quality properties in Bengkulu Province, Sumatra. Soil samples were collected from adjacent sites including natural secondary forest, bare land, cultivated land and grassland. The results show that land-use following forest clearance lowered saturated hydraulic conductivity (85%, porosity (10.50%, soil water content at field capacity (34%,C organic (27%, N total (26%, inorganic N (37%, soil microbial biomass C (32%, mineralizable C (22%, and particulate organic matter (50%, but slightly increased water soluble organic C. Specific respiration activi ty rates increased about 14% in cultivated soils compared to natural forest soils, indicating greater C turnover per labile C pool in the form of soil microbial biomass, thus decreased biologically active soil organic matter. Forest conversion tends to reduce the C,ffg/Crer for all deforested sites. All of deforested areas relatively have infertile soil, with the worst case found in cultivated field. The C^g/Crd of cultivated field s was about 24% less than that of remnant fo rest (1.07. Grassland apparently mainta ins only slightly higher soil C levels than the bare land. On average, degradation index of so il following forest clearance was 35% with the highest deterioration occurred in the bare land (38%. Fallowing the fields by naturally growth of Imperata cylindrica for about 15 yr in abandoned land after 3-5 years of cultivation did not improve the soil quality. Moreover, forest clearance has an impact on soil quality as resulted in the loss of a physically protected organic matter and reduction in some labile C pools, thus declined biological activity at disturbed

  7. Species richness pattern along altitudinal gradient in Central European beech forests

    Czech Academy of Sciences Publication Activity Database

    Hrivnák, R.; Gömöry, D.; Slezák, M.; Ujházy, K.; Hédl, Radim; Jarčuška, B.; Ujházyová, M.

    2014-01-01

    Roč. 49, č. 3 (2014), s. 425-441 ISSN 1211-9520 Institutional support: RVO:67985939 Keywords : altitude * beech-dominated forest * species richness Subject RIV: EF - Botanics Impact factor: 1.778, year: 2014

  8. Radon levels and transport parameters in Atlantic Forest soils

    International Nuclear Information System (INIS)

    Farias, E.E.G. de; Silva Neto, P.C. da; Souza, E.M. de; De Franca, E.J.; Hazin, C.A.

    2016-01-01

    In natural forest soils, the radon transport processes can be significantly intensified due to the contribution of living organism activities to soil porosity. In this paper, the first results of the radon concentrations were obtained for soil gas from the Atlantic Forest, particularly in the Refugio Ecologico Charles Darwin, Brazil. The estimation of permeability and radon exhalation rate were carried out in this conservation unit. For forested soils, radon concentrations as high as 40 kBq m -3 were found. Based on the radon concentrations and on the permeability parameter, the results indicated considerable radon hazard for human occupation in the neighborhood. (author)

  9. 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.

  10. Bioecology of pear thrips: distribution in forest soils

    Science.gov (United States)

    Margaret Skinner; Bruce L. Parker

    1991-01-01

    The vertical and horizontal distribution of pear thrips in Vermont sugar maple forest soils was investigated. In the fall, about 86% of the thrips were found in the upper 10 cm of soil, though a few were found as deep as 20 cm. No thrips were found in the leaf litter. Soil sampling tools to determine thrips populations within an entire forest were tested and a standard...

  11. Nitrous oxide emission inventory of German forest soils

    Science.gov (United States)

    Schulte-Bisping, Hubert; Brumme, Rainer; Priesack, Eckart

    2003-02-01

    Annual fluxes of N2O trace gas emissions were assessed after stratifying German forest soils into Seasonal Emission Pattern (SEP) and Background Emission Pattern (BEP). Broad-leaved forests with soil pH(KCl) ≤ 3.3 were assigned to have SEP, broad-leaved forests with soil pH(KCl) > 3.3 and all needle-leaved forests to have BEP. BEPs were estimated by a relationship between annual N2O emissions and carbon content of the O-horizon. SEPs were primarily controlled by temperature and moisture and simulated by the model Expert-N after calibration to a 9-year record of N2O measurements. Analysis with different climate and soil properties indicated that the model reacts highly sensitive to changes in soil temperature, soil moisture, and soil texture. A geographic information system (ARC/INFO) was used for a spatial resolution of 1 km × 1 km grid where land cover, dominant soil units, and hygro climate classes were combined. The mean annual N2O emission flux from German forest soils was estimated as 0.32 kg ha-1 yr-1. Broad-leaved forests with SEP had the highest emissions (2.05 kg ha-1 yr-1) followed by mixed forests (0.38 kg ha-1 yr-1), broad-leaved forests (0.37 kg ha-1 yr-1), and needle-leaved forests with BEP (0.17 kg ha-1 yr-1). The annual N2O emission from German forest soils was calculated as 3.26 Gg N2O-N yr-1. Although needle-leaved trees cover about 57% of the entire forest area in Germany, their contribution is low (0.96 Gg N2O-N yr-1). Broad-leaved forests cover about 22% of the forest area but have 55% higher emissions (1.49 Gg N2O-N yr-1) than needle-leaved. Mixed forests cover 21% of the area and contribute 0.81 Gg N2O-N yr-1. Compared to the total N2O emissions in Germany of 170 Gg N yr-1, forest soils contribute only 1.9%. However, there are some uncertainties in this emission inventory, which are intensely discussed.

  12. Species Richness and Phenology of Cerambycid Beetles in Urban Forest Fragments of Northern Delaware

    Science.gov (United States)

    K. Handley; J. Hough-Goldstein; L.M. Hanks; J.G. Millar; V. D' amico

    2015-01-01

    Cerambycid beetles are abundant and diverse in forests, but much about their host relationships and adult behavior remains unknown. Generic blends of synthetic pheromones were used as lures in traps, to assess the species richness, and phenology of cerambycids in forest fragments in northern Delaware. More than 15,000 cerambycid beetles of 69 species were trapped over...

  13. Terrain and vegetation structural influences on local avian species richness in two mixed-conifer forests

    Science.gov (United States)

    Jody C. Vogeler; Andrew T. Hudak; Lee A. Vierling; Jeffrey Evans; Patricia Green; Kerri T. Vierling

    2014-01-01

    Using remotely-sensed metrics to identify regions containing high animal diversity and/or specific animal species or guilds can help prioritize forest management and conservation objectives across actively managed landscapes. We predicted avian species richness in two mixed conifer forests, Moscow Mountain and Slate Creek, containing different management contexts and...

  14. Bird species richness and abundance in different forest types at ...

    African Journals Online (AJOL)

    The avifauna of differently disturbed forest types of Kakamega Afrotropical forest were compared from December 2004 to May 2005. A total of 11 220 individual birds comprising of 129 bird species were recorded. Significant differences in abundance of birds among Psidium guajava, Bischoffia javanica, mixed indigenous, ...

  15. The effects of forest destruction on the abundance, species richness ...

    African Journals Online (AJOL)

    SARAH

    2013-04-25

    Apr 25, 2013 ... compounds found in plants, animals, or microorganisms. ... fragmented and degraded With the exception of sacred forest ... best-known insects that are involved in pollinating flowers. ... The influence of landscape patterns on butterfly ..... history were recorded in the tropical rain forest areas but due to ...

  16. Local versus landscape-scale effects of anthropogenic land-use on forest species richness

    Science.gov (United States)

    Buffa, G.; Del Vecchio, S.; Fantinato, E.; Milano, V.

    2018-01-01

    The study investigated the effects of human-induced landscape patterns on species richness in forests. For 80 plots of fixed size, we measured human disturbance (categorized as urban/industrial and agricultural land areas), at 'local' and 'landscape' scale (500 m and 2500 m radius from each plot, respectively), the distance from the forest edge, and the size and shape of the woody patch. By using GLM, we analyzed the effects of disturbance and patch-based measures on both total species richness and the richness of a group of specialist species (i.e. the 'ancient forest species'), representing more specific forest features. Patterns of local species richness were sensitive to the structure and composition of the surrounding landscape. Among the landscape components taken into account, urban/industrial land areas turned out as the most threatening factor for both total species richness and the richness of the ancient forest species. However, the best models evidenced a different intensity of the response to the same disturbance category as well as a different pool of significant variables for the two groups of species. The use of groups of species, such as the ancient forest species pool, that are functionally related and have similar ecological requirements, may represent an effective solution for monitoring forest dynamics under the effects of external factors. The approach of relating local assessment of species richness, and in particular of the ancient forest species pool, to land-use patterns may play an important role for the science-policy interface by supporting and strengthening conservation and regional planning decision making.

  17. Sources of nitrous oxide emitted from European forest soils

    DEFF Research Database (Denmark)

    Ambus, P.; Zechmeister-Boltenstern, S.; Butterbach-Bahl, K.

    2006-01-01

    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...

  18. Radionuclide fractionation in a forest soil profile

    International Nuclear Information System (INIS)

    Rigol, A.; Vidal, M.; Rauret, G.

    1996-01-01

    Two alternative approaches, a sequential extraction scheme and the calculation of the variation of the distribution coefficient of radiocaesium in different K-Ca N H 4 scenarios, were used to study the behaviour and fractionation of this radionuclide in a forest soil profile. The first approach was applied to samples originating from an experiment in which the original L(litter) layer was replaced by an L layer contaminated with a radioactive aerosol, allowing a downward migration of radiocaesium. The samples belonged to different stages after the contamination. The second approach was applied to samples contaminated with soluble radiocaesium. The results indicate that the mineral matter seems to govern the behaviour of radiocaesium in case of direct condensed deposition or when radiocaesium is released from structural components of the organic matter phase. (author). 16 refs., 2 figs., 1 tab

  19. [Ants’ higher taxa as surrogates of species richness in a chronosequence of fallows, old-grown forests and agroforestry systems in the Eastern Amazon, Brazil].

    Science.gov (United States)

    Muñoz Gutiérrez, Jhonatan Andrés; Roussea, Guillaume Xavier; Andrade-Silva, Joudellys; Delabie, Jacques Hubert Charles

    2017-03-01

    Deforestation in Amazon forests is one of the main causes for biodiversity loss worldwide. Ants are key into the ecosystem because act like engineers; hence, the loss of ants’ biodiversity may be a guide to measure the loss of essential functions into the ecosystems. The aim of this study was to evaluate soil ant’s richness and to estimate whether higher taxa levels (Subfamily and Genus) can be used as surrogates of species richness in different vegetation types (fallows, old-growth forests and agroforestry systems) in Eastern Amazon. The samples were taken in 65 areas in the Maranhão and Pará States in the period 2011-2014. The sampling scheme followed the procedure of Tropical Soil Biology and Fertility (TSBF). Initially, the vegetation types were characterized according to their age and estimated species richness. Linear and exponential functions were applied to evaluate if higher taxa can be used as surrogates and correlated with the Pearson coefficient. In total, 180 species distributed in 60 genera were identified. The results showed that ant species richness was higher in intermediate fallows (88) and old secondary forest (76), and was lower in agroforestry systems (38) and mature riparian forest (35). The genus level was the best surrogate to estimate the ant’s species richness across the different vegetation types, and explained 72-97 % (P agroforestry systems may contribute in the conservation of Eastern Amazon ant community.

  20. Management impacts on forest floor and soil organic carbon in northern temperate forests of the US

    Science.gov (United States)

    Coeli M. Hoover

    2011-01-01

    The role of forests in the global carbon cycle has been the subject of a great deal of research recently, but the impact of management practices on forest soil dynamics at the stand level has received less attention. This study used six forest management experimental sites in five northern states of the US to investigate the effects of silvicultural treatments (light...

  1. Carbon stocks in tree biomass and soils of German forests

    Directory of Open Access Journals (Sweden)

    Wellbrock Nicole

    2017-06-01

    Full Text Available Close to one third of Germany is forested. Forests are able to store significant quantities of carbon (C in the biomass and in the soil. Coordinated by the Thünen Institute, the German National Forest Inventory (NFI and the National Forest Soil Inventory (NFSI have generated data to estimate the carbon storage capacity of forests. The second NFI started in 2002 and had been repeated in 2012. The reporting time for the NFSI was 1990 to 2006. Living forest biomass, deadwood, litter and soils up to a depth of 90 cm have stored 2500 t of carbon within the reporting time. Over all 224 t C ha-1 in aboveground and belowground biomass, deadwood and soil are stored in forests. Specifically, 46% stored in above-ground and below-ground biomass, 1% in dead wood and 53% in the organic layer together with soil up to 90 cm. Carbon stocks in mineral soils up to 30 cm mineral soil increase about 0.4 t C ha-1 yr-1 stocks between the inventories while the carbon pool in the organic layers declined slightly. In the living biomass carbon stocks increased about 1.0 t C ha-1 yr-1. In Germany, approximately 58 mill. tonnes of CO2 were sequestered in 2012 (NIR 2017.

  2. Agrogenic degradation of soils in Krasnoyarsk forest-steppe

    Science.gov (United States)

    Shpedt, A. A.; Trubnikov, Yu. N.; Zharinova, N. Yu.

    2017-10-01

    Agrogenic degradation of soils in Krasnoyarsk forest-steppe was investigated. Paleocryogenic microtopography of microlows and microhighs in this area predetermined the formation of paragenetic soil series and variegated soil cover. Specific paleogeographic conditions, thin humus horizons and soil profiles, and long-term agricultural use of the land resulted in the formation of soils unstable to degradation processes and subjected to active wind and water erosion. Intensive mechanical soil disturbances during tillage and long-term incorporation of the underlying Late Pleistocene (Sartan) calcareous silty and clay loams into the upper soil horizons during tillage adversely affected the soil properties. We determined the contents of total and labile humus and easily decomposable organic matter and evaluated the degree of soil exhaustion. It was concluded that in the case of ignorance of the norms of land use and soil conservation practices, intense soil degradation would continue leading to complete destruction of the soil cover within large areas.

  3. Richness and Abundance of Ichneumonidae in a Fragmented Tropical Rain Forest.

    Science.gov (United States)

    Ruiz-Guerra, B; Hanson, P; Guevara, R; Dirzo, R

    2013-10-01

    Because of the magnitude of land use currently occurring in tropical regions, the local loss of animal species due to habitat fragmentation has been widely studied, particularly in the case of vertebrates. Many invertebrate groups and the ichneumonid wasps in particular, however, have been poorly studied in this context, despite the fact that they are one of the most species-rich groups and play an important role as regulators of other insect populations. Here, we recorded the taxonomic composition of ichneumonid parasitoids and assessed their species richness, abundance, similarity, and dominance in the Los Tuxtlas tropical rain forest, Mexico. We compared two forest types: a continuous forest (640 ha) and a forest fragment (19 ha). We sampled ichneumonids using four malaise traps in both forest types during the dry (September-October) and rainy (March-April) seasons. A total of 104 individuals of Ichneumonidae belonging to 11 subfamilies, 18 genera, and 42 species were collected in the continuous forest and 11 subfamilies, 15 genera, and 24 species were collected in the forest fragment. Species richness, abundance, and diversity of ichneumonids were greater in the continuous forest than in the forest fragment. We did not detect differences between seasons. Species rank/abundance curves showed that the ichneumonid community between the forest types was different. Species similarity between forest types was low. The most dominant species in continuous forest was Neotheronia sp., whereas in the forest fragment, it was Orthocentrus sp. Changes in the ichneumonid wasp community may compromise important tropical ecosystem processes.

  4. Nitrogen Deposition Effects on Soil Carbon Dynamics in Temperate Forests

    DEFF Research Database (Denmark)

    Ginzburg Ozeri, Shimon

    Soils contain the largest fraction of terrestrial carbon (C). Understanding the factors regulating the decomposition and storage of soil organic matter (SOM) is essential for predictions of the C sink strength of the terrestrial environment in the light of global change. Elevated long-term nitrog...... implications for modelling the carbon sink-strength of temperate forests under global change.......Soils contain the largest fraction of terrestrial carbon (C). Understanding the factors regulating the decomposition and storage of soil organic matter (SOM) is essential for predictions of the C sink strength of the terrestrial environment in the light of global change. Elevated long-term nitrogen...... (N) deposition into forest ecosystems has been increasing globally and was hypothesized to raise soil organic C (SOC) stocks by increasing forest productivity and by reducing SOM decomposition. Yet, these effects of N deposition on forest SOC stocks are uncertain and largely based on observations...

  5. Structure, richness and composition of arboreal plants in a cloud thinning forest of Tolima (Colombia)

    International Nuclear Information System (INIS)

    Campo Kurmen, Juan Manuel

    2010-01-01

    Structure, richness, and floristic composition of the woody elements of the selective logging forest of the Vereda Dantas, (Ibague, Tolima, Colombia), where studied in a 0.1 ha plot sampled for all individuals ≥2.5 cm dbh. the forest is characterized by scarcity of lianas and hemiepiphytic, absence of typical families of the Colombian cloud forests between 2000 and 2500 m (Araceae, Ericaceae, Myrtaceae, Meliaceae and Aquifoliaceae), and richness increment of the Sabiaceae and Euphorbiaceae. Compared to others cloud forest from the Colombian Andes and the Neotropic, it has, fewer individuals (237 individuals ≥2.5 cm dbh per 0.1 ha) and more large trees (39.7% of individuals ≥10 cm dbh per 0.1 ha). The forest has a lower woody species richness (75 species ≥2.5 cm dbh per 0.1 ha). Apparently, the effects of selective timber extraction on structure, richness, and floristic composition are decrease floristic richness and density of individuals, decrease of lianas density and richness, and more individuals of secondary species, likes: Hedyosmum goudotianum Slms-Laubach var. goudatianum, Miconia resima Naud, and Palicourea calophlebia Standl.

  6. A comparison of soil-moisture loss from forested and clearcut areas in West Virginia

    Science.gov (United States)

    Charles A. Troendle

    1970-01-01

    Soil-moisture losses from forested and clearcut areas were compared on the Fernow Experimental Forest. As expected, hardwood forest soils lost most moisture while revegetated clearcuttings, clearcuttings, and barren areas lost less, in that order. Soil-moisture losses from forested soils also correlated well with evapotranspiration and streamflow.

  7. 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.

  8. Sample sizes to control error estimates in determining soil bulk density in California forest soils

    Science.gov (United States)

    Youzhi Han; Jianwei Zhang; Kim G. Mattson; Weidong Zhang; Thomas A. Weber

    2016-01-01

    Characterizing forest soil properties with high variability is challenging, sometimes requiring large numbers of soil samples. Soil bulk density is a standard variable needed along with element concentrations to calculate nutrient pools. This study aimed to determine the optimal sample size, the number of observation (n), for predicting the soil bulk density with a...

  9. Forest Soil Productivity on the Southern Long-Term Soil Productivity Sites at Age 5

    Science.gov (United States)

    D. Andrew Scott; Allan E. Tiarks; Felipe G. Sanchez; Michael Elliott-Smith; Rick Stagg

    2004-01-01

    Forest management operations have the potential to reduce soil productivity through organic matter and nutrient removal and soil compaction. We measured pine volume, bulk density, and soil and foliar nitrogen and phosphorus at age 5 on the 13 southern Long-Term Soil Productivity study sites. The treatments were organic matter removal [bole only (BO), whole tree (WT),...

  10. Revegetation of coal mine soil with forest litter

    Energy Technology Data Exchange (ETDEWEB)

    Day, A.D.; Ludeke, K.L.; Thames, J.L.

    1986-11-01

    Forest litter, a good source of organic matter and seeds, was applied on undisturbed soil and on coal mine (spoils) in experiments conducted on the Black Mesa Coal Mine near Kayenta, Arizona over a 2-year period (1977-1978). Germination, seedling establishment, plant height and ground cover were evaluated for two seeding treatments (forest litter and no forest litter) and two soil moisture treatments (natural rainfall and natural rainfall plus irrigation). The forest litter was obtained at random from the Coconino National Forest, broadcast over the surface of the soil materials and incorporated into the surface 5 cm of each soil material. Germination, seedling establishment, plant height and ground cover on undisturbed soil and coal mine soil were higher when forest litter was applied than when it was not applied and when natural rainfall was supplemented with sprinkler irrigation than when rainfall was not supplemented with irrigation. Applications of forest litter and supplemental irrigation may ensure successful establishment of vegetation on areas disturbed by open-pit coal mining.

  11. Coastal Plain Soil Fertility Degradation And Natural Forest Ecosystem Regeneration

    Science.gov (United States)

    Casagrande, J. C.; Sato, C. A.; Reis-Duarte, R. M.; Soares, M. R.; Galvão Bueno, M. S.

    2009-04-01

    The sand coastal plain vegetation (Restinga Forest) has been described as an ecosystem associated with the Atlantic Forest, constituted of mosaics, which occur in areas of great ecological diversity, particularly the features of the soil which mostly influence the forest, therefore assigned as edaphic community. The Restinga forest is one of the most fragile, showing low resilience to human damage This work was carried out in several points (14) of Restinga Forest (six low - trees from 3 to 10 m high - and eight high forest - trees from 10 to 15 m high) in the litoral coast of the state of São Paulo. Each sample was made of 15 subsamples of each area collected in each depth (one in 0 - 5, 5 - 10, 10 - 15, 15 - 20, and another in 0 - 20, 20 - 40, 40 and 60 cm). Soil characteristics analyzed were pH, P, Na, K, Ca, Mg, S, H + Al, Al, B, Cu, Fe, Mn, Zn contents and base saturation, cation exchange capacity and aluminum saturation. The vegetation physiognomies of Restinga forest (low and high) were associated with soil results and with the history of human occupation. The soils are sandy (2 to 4% of clay), resulting in a low capacity of nutrient retention. Soil fertility analysis to low and high Restinga forest were similar and showed very low contents of phosphorous, calcium and magnesium in all areas investigated. The base saturation was low due to low amounts of Na, K, Ca and Mg. Base saturation presents low level in all cases, less than 10, indicating low nutritional reserve in the soil. The aluminum saturation values varied from 58 to 69%. The level of calcium and magnesium were low in the subsurface soil layer mainly, associate with high aluminum saturation, representing an limiting factor for the root system development in depth. If soil fertility parameters do not show any significant difference between low and high Restinga physiognomy, what make distinction is the recuperation time. In the areas of high Forest can be note a too long time of recuperation

  12. Soil mineralogy and microbes determine forest life history strategy and carbon cycling in humid tropical forests

    Science.gov (United States)

    Soong, J.; Verbruggen, E.; Peñuelas, J.; Janssens, I. A.; Grau, O.

    2017-12-01

    Tropical forests account for over one third of global terrestrial gross primary productivity and cycle more C than any other ecosystem on Earth. However, we still lack a mechanistic understanding of how such high productivity is maintained on the old, highly weathered and phosphorus depleted soils in the tropics. We hypothesized that heterogeneity in soil texture, mineralogy and microbial community composition may be the major drivers of differences in soil C storage and P limitation across tropical forests. We sampled 12 forest sites across a 200 km transect in the humid neo-tropics of French Guiana that varied in soil texture, precipitation and mineralogy. We found that soil texture was a major driver of soil carbon stocks and forest life history strategy, where sandy forests have lower soil C stocks, slower turnover and decomposition and a more closed nutrient cycle while clayey forests have higher soil C stocks, faster turnover and a more leaky nutrient cycle (using natural abundance stable isotope evidence). We found that although the presence of Al and Fe oxides in the clayey soils occludes soil organic matter and P, a greater abundance of arbuscular mycorrhizal fungi help forests to access occluded P in clayey soils fueling higher turnover and faster decomposition rates. Evidence from a laboratory incubation of tropical soils with nutrient additions further demonstrates the de-coupling of microbial P demands from C:N limitations providing further evidence for the need to examine microbial stoichiometry to explain C cycling in the P-limited tropics. We argue that microbial community composition and physiological demands, constrained within the limitations of soil mineralogical reactivity, largely controls nutrient and C cycling in tropical forest soils. Together our observational field study and laboratory incubation provide a unique dataset to shed light on the mineralogical and microbial controls on C and nutrient cycling in tropical soils. By integrating

  13. The Arbuscular Mycorrhizal Fungus Funneliformis mosseae Alters Bacterial Communities in Subtropical Forest Soils during Litter Decomposition

    Directory of Open Access Journals (Sweden)

    Heng Gui

    2017-06-01

    Full Text Available Bacterial communities and arbuscular mycorrhizal fungi (AMF co-occur in the soil, however, the interaction between these two groups during litter decomposition remains largely unexplored. In order to investigate the effect of AMF on soil bacterial communities, we designed dual compartment microcosms, where AMF (Funneliformis mosseae was allowed access (AM to, or excluded (NM from, a compartment containing forest soil and litterbags. Soil samples from this compartment were analyzed at 0, 90, 120, 150, and 180 days. For each sample, Illumina sequencing was used to assess any changes in the soil bacterial communities. We found that most of the obtained operational taxonomic units (OTUs from both treatments belonged to the phylum of Proteobacteria, Acidobacteria, and Actinobacteria. The community composition of bacteria at phylum and class levels was slightly influenced by both time and AMF. In addition, time and AMF significantly affected bacterial genera (e.g., Candidatus Solibacter, Dyella, Phenylobacterium involved in litter decomposition. Opposite to the bacterial community composition, we found that overall soil bacterial OTU richness and diversity are relatively stable and were not significantly influenced by either time or AMF inoculation. OTU richness at phylum and class levels also showed consistent results with overall bacterial OTU richness. Our study provides new insight into the influence of AMF on soil bacterial communities at the genus level.

  14. Modeling dynamics of {sup 137}Cs in forest surface environments: Application to a contaminated forest site near Fukushima and assessment of potential impacts of soil organic matter interactions

    Energy Technology Data Exchange (ETDEWEB)

    Ota, Masakazu, E-mail: ohta.masakazu@jaea.go.jp; Nagai, Haruyasu; Koarashi, Jun

    2016-05-01

    A process-based model for {sup 137}Cs transfer in forest surface environments was developed to assess the dynamic behavior of Fukushima-derived {sup 137}Cs in a Japanese forest. The model simulation successfully reproduced the observed data from 3 year migration of {sup 137}Cs in the organic and mineral soil layers at a contaminated forest near Fukushima. The migration of {sup 137}Cs from the organic layer to the mineral soil was explained by the direct deposition pattern on the forest floor and the turnover of litter materials in the organic layer under certain ecological conditions. Long-term predictions indicated that more than 90% of the deposited {sup 137}Cs would remain within the top 5 cm of the soil for up to 30 years after the accident, suggesting that the forest acts as an effective long-term reservoir of {sup 137}Cs with limited transfer via the groundwater pathway. The model was also used to explore the potential impacts of soil organic matter (SOM) interactions on the mobility and bioavailability of {sup 137}Cs in the soil–plant system. The simulation results for hypothetical organic soils with modified parameters of {sup 137}Cs turnover revealed that the SOM-induced reduction of {sup 137}Cs adsorption elevates the fraction of dissolved {sup 137}Cs in the soil solution, thereby increasing the soil-to-plant transfer of {sup 137}Cs without substantially altering the fractional distribution of {sup 137}Cs in the soil. Slower fixation of {sup 137}Cs on the flayed edge site of clay minerals and enhanced mobilization of the clay-fixed {sup 137}Cs in organic-rich soils also appeared to elevate the soil-to-plant transfer of {sup 137}Cs by increasing the fraction of the soil-adsorbed (exchangeable) {sup 137}Cs. A substantial proportion (approximate 30%–60%) of {sup 137}Cs in these organic-rich soils was transferred to layers deeper than 5 cm decades later. These results suggested that SOM influences the behavior of {sup 137}Cs in forests over a prolonged

  15. Acidification of forest soil in Russia: From 1893 to present

    Science.gov (United States)

    Lapenis, A.G.; Lawrence, G.B.; Andreev, A.A.; Bobrov, A.A.; Torn, M.S.; Harden, J.W.

    2004-01-01

    It is commonly believed that fine-textured soils developed on carbonate parent material are well buffered from possible acidification. There are no data, however, that document resistance of such soils to acidic deposition exposure on a timescale longer than 30-40 years. In this paper, we report on directly testing the long-term buffering capacity of nineteenth century forest soils developed on calcareous silt loam. In a chemical analysis comparing archived soils with modern soils collected from the same locations ???100 years later, we found varying degrees of forest-soil acidification in the taiga and forest steppe regions. Land-use history, increases in precipitation, and acidic deposition were contributing factors in acidification. The acidification of forest soil was documented through decreases in soil pH and changes in concentrations of exchangeable calcium and aluminum, which corresponded with changes in communities of soil microfauna. Although acidification was found at all three analyzed locations, the trends in soil chemistry were most pronounced where the highest loading of acidic deposition had taken place. Copyright 2004 by the American Geophysical Union.

  16. [Effects of forest regeneration patterns on the quantity and chemical structure of soil solution dissolved organic matter in a subtropical forest.

    Science.gov (United States)

    Yuan, Xiao Chun; Lin, Wei Sheng; Pu, Xiao Ting; Yang, Zhi Rong; Zheng, Wei; Chen, Yue Min; Yang, Yu Sheng

    2016-06-01

    Using the negative pressure sampling method, the concentrations and spectral characte-ristics of dissolved organic matter (DOM) of soil solution were studied at 0-15, 15-30, 30-60 cm layers in Castanopsis carlesii forest (BF), human-assisted naturally regenerated C. carlesii forest (RF), C. carlesii plantation (CP) in evergreen broad-leaved forests in Sanming City, Fujian Pro-vince. The results showed that the overall trend of dissolved organic carbon (DOC) concentrations in soil solution was RF>CP>BF, and the concentration of dissolved organic nitrogen (DON) was highest in C. carlesii plantation. The concentrations of DOC and DON in surface soil (0-15 cm) were all significantly higher than in the subsurface (30-60 cm). The aromatic index (AI) was in the order of RF>CP>BF, and as a whole, the highest AI was observed in the surface soil. Higher fluorescence intensity and a short wave absorption peak (320 nm) were observed in C. carlesii plantation, suggesting the surface soil of C. carlesii plantation was rich in decomposed substance content, while the degree of humification was lower. A medium wave absorption peak (380 nm) was observed in human-assisted naturally regenerated C. carlesii forest, indicating the degree of humification was higher which would contribute to the storage of soil fertility. In addition, DOM characte-ristics in 30-60 cm soil solution were almost unaffected by forest regeneration patterns.

  17. Soil fluxes of methane, nitrous oxide, and nitric oxide from aggrading forests in coastal Oregon

    Science.gov (United States)

    Erickson, Heather E.; Perakis, Steven S.

    2014-01-01

    Soil exchanges of greenhouse and other gases are poorly known for Pacific Northwest forests where gradients in nutrient availability and soil moisture may contribute to large variations in fluxes. Here we report fluxes of methane (CH4), nitrous oxide (N2O), and nitric oxide (NO) over multiple seasons from three naturally N-rich, aggrading forests of coastal Oregon, USA. Mean methane uptake rates (3.2 mg CH4 m−2 d−1) were high compared with forests globally, negatively related to water-filled pore space (WFPS), but unrelated to N availability or temperature. Emissions of NO (6.0 μg NO–N m−2 h−1) exceeded N2O (1.4 μg N2O–N m−2 h−1), except when WFPS surpassed 55%. Spatial variation in NO fluxes correlated positively with soil nitrate concentrations (which generally exceeded ammonium concentrations, indicating the overall high N status for the sites) and negatively with soil pH, and at one site increased with basal area of N2-fixing red alder. Combined NO and N2O emissions were greatest from the site with highest annual net N mineralization and lowest needle litterfall C/N. Our findings of high CH4 uptake and NO/N2O ratios generally >1 most likely reflect the high porosity of the andic soils underlying the widespread regenerating forests in this seasonally wet region.

  18. Digging a Little Deeper: Microbial Communities, Molecular Composition and Soil Organic Matter Turnover along Tropical Forest Soil Depth Profiles

    Science.gov (United States)

    Pett-Ridge, J.; McFarlane, K. J.; Heckman, K. A.; Reed, S.; Green, E. A.; Nico, P. S.; Tfaily, M. M.; Wood, T. E.; Plante, A. F.

    2016-12-01

    Tropical forest soils store more carbon (C) than any other terrestrial ecosystem and exchange vast amounts of CO2, water, and energy with the atmosphere. Much of this C is leached and stored in deep soil layers where we know little about its fate or the microbial communities that drive deep soil biogeochemistry. Organic matter (OM) in tropical soils appears to be associated with mineral particles, suggesting deep soils may provide greater C stabilization. However, few studies have evaluated sub-surface soils in tropical ecosystems, including estimates of the turnover times of deep soil C, the sensitivity of this C to global environmental change, and the microorganisms involved. We quantified bulk C pools, microbial communities, molecular composition of soil organic matter, and soil radiocarbon turnover times from surface soils to 1.5m depths in multiple soil pits across the Luquillo Experimental Forest, Puerto Rico. Soil C, nitrogen, and root and microbial biomass all declined exponentially with depth; total C concentrations dropped from 5.5% at the surface to communities in surface soils (Acidobacteria and Proteobacteria) versus those below the active rooting zone (Verrucomicrobia and Thaumarchaea). High resolution mass spectrometry (FTICR-MS) analyses suggest a shift in the composition of OM with depth (especially in the water soluble fraction), an increase in oxidation, and decreasing H/C with depth (indicating higher aromaticity). Additionally, surface samples were rich in lignin-like compounds of plant origin that were absent with depth. Soil OM 14C and mean turnover times were variable across replicate horizons, ranging from 3-1500 years at the surface, to 5000-40,000 years at depth. In comparison to temperate deciduous forests, these 14C values reflect far older soil C. Particulate organic matter (free light fraction), with a relatively modern 14C was found in low but measureable concentration in even the deepest soil horizons. Our results indicate these

  19. Physicochemical Properties of the Soils of Wassaniya Forest ...

    African Journals Online (AJOL)

    1 Department of Forestry and Fisheries, Kebbi State University of Science and Technology, Aliero. 2 Department ... Forest Reserve in Tangaza Local Government Area of Sokoto State, Nigeria. ... Increase in organic carbon content of the soil is.

  20. Avian species richness in relation to intensive forest management practices in early seral tree plantations.

    Science.gov (United States)

    Jones, Jay E; Kroll, Andrew J; Giovanini, Jack; Duke, Steven D; Ellis, Tana M; Betts, Matthew G

    2012-01-01

    Managers of landscapes dedicated to forest commodity production require information about how practices influence biological diversity. Individual species and communities may be threatened if management practices truncate or simplify forest age classes that are essential for reproduction and survival. For instance, the degradation and loss of complex diverse forest in young age classes have been associated with declines in forest-associated Neotropical migrant bird populations in the Pacific Northwest, USA. These declines may be exacerbated by intensive forest management practices that reduce hardwood and broadleaf shrub cover in order to promote growth of economically valuable tree species in plantations. We used a Bayesian hierarchical model to evaluate relationships between avian species richness and vegetation variables that reflect stand management intensity (primarily via herbicide application) on 212 tree plantations in the Coast Range, Oregon, USA. Specifically, we estimated the influence of broadleaf hardwood vegetation cover, which is reduced through herbicide applications, on bird species richness and individual species occupancy. Our model accounted for imperfect detection. We used average predictive comparisons to quantify the degree of association between vegetation variables and species richness. Both conifer and hardwood cover were positively associated with total species richness, suggesting that these components of forest stand composition may be important predictors of alpha diversity. Estimates of species richness were 35-80% lower when imperfect detection was ignored (depending on covariate values), a result that has critical implications for previous efforts that have examined relationships between forest composition and species richness. Our results revealed that individual and community responses were positively associated with both conifer and hardwood cover. In our system, patterns of bird community assembly appear to be associated with

  1. 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...

  2. Paradise lost: alien plant invaders compromising productive, rich state forests

    Science.gov (United States)

    Nancy J. Loewenstein; James H. Miller; Erwin Chamblis

    2008-01-01

    Kudzu and Chinese privet along Alabama roadways are a familiar sight and Japanese honeysuckle is so commonplace it has practically become a part of Southern culture. But are these and other invasive plants really having a negative impact on forests? Just how bad is the invasive plant problem? What are the most effective ways to combat invasive plants?

  3. Urbanization in China drives soil acidification of Pinus massoniana forests

    Science.gov (United States)

    Huang, Juan; Zhang, Wei; Mo, Jiangming; Wang, Shizhong; Liu, Juxiu; Chen, Hao

    2015-09-01

    Soil acidification instead of alkalization has become a new environmental issue caused by urbanization. However, it remains unclear the characters and main contributors of this acidification. We investigated the effects of an urbanization gradient on soil acidity of Pinus massoniana forests in Pearl River Delta, South China. The soil pH of pine forests at 20-cm depth had significantly positive linear correlations with the distance from the urban core of Guangzhou. Soil pH reduced by 0.44 unit at the 0-10 cm layer in urbanized areas compared to that in non-urbanized areas. Nitrogen deposition, mean annual temperature and mean annual precipitation were key factors influencing soil acidification based on a principal component analysis. Nitrogen deposition showed significant linear relationships with soil pH at the 0-10 cm (for ammonium N (-N), P greatly contributed to a significant soil acidification occurred in the urbanized environment.

  4. Woody plant richness and NDVI response to drought events in Catalonian (northeastern Spain) forests.

    Science.gov (United States)

    Lloret, F; Lobo, A; Estevan, H; Maisongrande, P; Vayreda, J; Terradas, J

    2007-09-01

    The role of species diversity on ecosystem resistance in the face of strong environmental fluctuations has been addressed from both theoretical and experimental viewpoints to reveal a variety of positive and negative relationships. Here we explore empirically the relationship between the richness of forest woody species and canopy resistance to extreme drought episodes. We compare richness data from an extensive forest inventory to a temporal series of satellite imagery that estimated drought impact on forest canopy as NDVI (normalized difference vegetation index) anomalies of the dry summer in 2003 in relation to records of previous years. We considered five different types of forests that are representative of the main climatic and altitudinal gradients of the region, ranging from lowland Mediterranean to mountain boreal-temperate climates. The observed relationship differed among forest types and interacted with the climate, summarised by the Thorntwaite index. In Mediterranean Pinus halepensis forests, NDVI decreased during the drought. This decrease was stronger in forests with lower richness. In Mediterranean evergreen forests of Quercus ilex, drought did not result in an overall NDVI loss, but lower NDVI values were observed in drier localities with lower richness, and in more moist localities with higher number of species. In mountain Pinus sylvestris forests NDVI decreased, mostly due to the drought impact on drier localities, while no relation to species richness was observed. In moist Fagus sylvatica forests, NDVI only decreased in plots with high richness. No effect of drought was observed in the high mountain Pinus uncinata forests. Our results show that a shift on the diversity-stability relationship appears across the regional, climatic gradient. A positive relationship appears in drier localities, supporting a null model where the probability of finding a species able to cope with drier conditions increases with the number of species. However, in

  5. Does species richness affect fine root biomass and production in young forest plantations?

    DEFF Research Database (Denmark)

    Domisch, Timo; Finér, Leena; Dawud, Seid Muhie

    2015-01-01

    Tree species diversity has been reported to increase forest ecosystem above-ground biomass and productivity, but little is known about below-ground biomass and production in diverse mixed forests compared to single-species forests. For testing whether species richness increases below-ground biomass...... and production and thus complementarity between forest tree species in young stands, we determined fine root biomass and production of trees and ground vegetation in two experimental plantations representing gradients in tree species richness. Additionally, we measured tree fine root length and determined...... be that these stands were still young, and canopy closure had not always taken place, i.e. a situation where above- or below-ground competition did not yet exist. Another reason could be that the rooting traits of the tree species did not differ sufficiently to support niche differentiation. Our results suggested...

  6. The microbiology of forest soils: a literature review

    Energy Technology Data Exchange (ETDEWEB)

    Hendrickson, O; Robinson, J B

    1982-01-01

    This report discusses the activities of two major groups of forest soil microorganisms, the bacteria and the fungi. Special attention is paid to their participation in the decay of major forest litter substrates, including leaves, branches and roots. The influence of bacteria and fungi in symbiotic associations with woody plant roots upon the cycles of carbon and nitrogen is described. The impacts of certain forest mamagement alternatives are assessed in terms of the creation of elimination of suitable environments for the activity of soil microorganisms. A bibliography is included. 507 refs., 1 tab.

  7. Contributions of Ectomycorrhizal Fungal Mats to Forest Soil Carbon Cycles

    Science.gov (United States)

    Kluber, L. A.; Phillips, C. L.; Myrold, D. D.; Bond, B. J.

    2008-12-01

    Ectomycorrhizal (EM) fungi are a prominent and ubiquitous feature of forest soils, forming symbioses with most tree species, yet little is known about the magnitude of their impact on forest carbon cycles. A subset of EM fungi form dense, perennial aggregations of hyphae, which have elevated respiration rates compared with neighboring non-mat soils. These mats are a foci of EM activity and thereby a natural laboratory for examining how EM fungi impact forest soils. In order to constrain the contributions of EM fungi to forest soil respiration, we quantified the proportion of respiration derived from EM mat soils in an old-growth Douglas-fir stand in western Oregon. One dominant genus of mat-forming fungi, Piloderma, covered 56% of the soil surface area. Piloderma mats were monitored for respiration rates over 15 months and found to have on average 10% higher respiration than non-mat soil. At the stand level, this amounts to roughly 6% of soil respiration due to the presence of Piloderma mats. We calculate that these mats may constitute 27% of autotrophic respiration, based on respiration rates from trenched plots in a neighboring forest stand. Furthermore, enzyme activity and microbial community profiles in mat and non-mat soil provide evidence that specialized communities utilizing chitin contribute to this increased efflux. With 60% higher chitinase activity in mats, the breakdown of chitin is likely an important carbon flux while providing carbon and nitrogen to the microbial communities associated with mats. Quantitative PCR showed similar populations of fungi and bacteria in mat and non-mat soils; however, community analysis revealed distinct fungal and bacterial communities in the two soil types. The higher respiration associated with EM mats does not appear to be due only to a proliferation of EM fungi, but to a shift in overall community composition to organisms that efficiently utilize the unique resources available within the mat, including plant and

  8. Richness of Ancient Forest Plant Species Indicates Suitable Habitats for Macrofungi

    Czech Academy of Sciences Publication Activity Database

    Hofmeister, J.; Hošek, J.; Brabec, Marek; Dvořák, D.; Beran, M.; Deckerová, H.; Burel, J.; Kříž, M.; Borovička, Jan; Běťák, J.; Vašutová, Martina

    2014-01-01

    Roč. 23, č. 8 (2014), s. 2015-2031 ISSN 0960-3115 Grant - others:GA MŽP(CZ) SP/2D1/146/08 Institutional support: RVO:67985807 ; RVO:67985831 ; RVO:67179843 Keywords : diversity * forest continuity * forest management * Herb-layer plant species * red-listed species * species richness * surrogacy Subject RIV: BB - Applied Statistics, Operational Research; EH - Ecology, Behaviour (GLU-S); EH - Ecology, Behaviour (UEK-B) Impact factor: 2.365, year: 2014

  9. Does tree species richness attenuate the effect of experimental irrigation and drought on decomposition rate in young plantation forests?

    Science.gov (United States)

    Masudur Rahman, Md; Verheyen, Kris; Castagneyrol, Bastien; Jactel, Hervé; Carnol, Monique

    2017-04-01

    Expected changes in precipitation in Europe due to climate change are likely to affect soil organic matter (OM) transformation. In forests, increasing tree species diversity might modulate the effect of changed precipitation. We evaluated the effect of tree species richness on the decomposition and stabilization rate in combination with reduced precipitation (FORBIO, Belgium) and irrigation treatment (ORPHEE, southern France) in young (6-8 yr.) experimental plantations. The species richness were one to four in FORBIO and one to five in ORPHEE. Twenty four rainout shelters of 3 m × 3 m were built around oak and beech trees in FORBIO plantation to impose a reduced precipitation treatment, whereas four of the eight blocks (175 m×100 m) in ORPHEE plantation was subjected to irrigation treatment. These treatments resulted in about 4% less soil moisture in FORBIO and about 7% higher soil moisture in ORPHEE compared to control. Commercially available green and rooibos tea bags were buried in the soil at 5-7 cm depth to measure two decomposition indices, known as 'tea bag index' (TBI). These TBI are (i) decomposition rate (k) and (ii) stabilization rate (S). The results showed no species richness effect on TBI indices in both reduced precipitation and irrigation treatment. In FORBIO, reduced precipitation resulted in decreased k and increased S compared to control around the beech trees only. In ORPHEE, both k and S were higher in the irrigation treatment compared to control. Overall, TBI indices were higher in FORBIO than ORPHEE and this might be explained by the sandy soils and poor nutrient content at the ORPHEE site. These results suggest that OM decomposition rate may be slower in drier condition and OM stabilization rate may be slower or faster in drier condition, depending on the site quality. The absence of tree species effects on OM transformation indicates that tree species richness would not be able to modulate the effects of changed precipitation patterns in

  10. Moss-nitrogen input to boreal forest soils

    DEFF Research Database (Denmark)

    Rousk, Kathrin; Jones, Davey; DeLuca, Thomas

    2014-01-01

    Cyanobacteria living epiphytically on mosses in pristine, unpolluted areas fix substantial amounts of atmospheric nitrogen (N) and therefore represent a primary source of N in N-limited boreal forests. However, the fate of this N is unclear, in particular, how the fixed N2 enters the soil and bec...... and that transfer of N to the soil is not facilitated by fungal hyphae....

  11. The forest ecosystem of southeast Alaska: 5. Soil mass movement.

    Science.gov (United States)

    Douglas N. Swanston

    1974-01-01

    Research in southeast Alaska has identified soil mass movement as the dominant erosion process, with debris avalanches and debris flows the most frequent events on characteristically steep, forested slopes. Periodically high soil water levels and steep slopes are controlling factors. Bedrock structure and the rooting characteristics of trees and other vegetation exert...

  12. Soil Quality Index Determination Models for Restinga Forest

    Science.gov (United States)

    Bonilha, R. M.; Casagrande, J. C.; Soares, R. M.

    2012-04-01

    The Restinga Forest is a set of plant communities in mosaic, determined by the characteristics of their substrates as a result of depositional processes and ages. In this complex mosaic are the physiognomies of restinga forests of high-stage regeneration (high restinga) and middle stage of regeneration (low restinga), each with its plant characteristics that differentiate them. Located on the coastal plains of the Brazilian coast, suffering internal influences both the continental slopes, as well as from the sea. Its soils come from the Quaternary and are subject to constant deposition of sediments. The climate in the coastal type is tropical (Köppen). This work was conducted in four locations: (1) Anchieta Island, Ubatuba, (2) Juréia-Itatins Ecological Station, Iguape, (3) Vila das Pedrinhas, Comprida Island; and (4) Cardoso Island, Cananeia. The soil samples were collect at a depths of 0 to 5, 0-10, 0-20, 20-40 and 40 to 60cm for the chemical and physical analysis. Were studied the additive and pondering additive models to evaluate soil quality. It was concluded: a) the comparative additive model produces quantitative results and the pondering additive model quantitative results; b) as the pondering additive model, the values of Soil Quality Index (SQI) for soils under forest of restinga are low and realistic, demonstrating the small plant biomass production potential of these soils, as well as their low resilience; c) the values of SQI similar to areas with and without restinga forest give quantitative demonstration of the restinga be considered as soil phase; d) restinga forest, probably, is maintained solely by the cycling of nutrients in a closed nutrient cycling; e) for the determination of IQS for soils under restinga vegetation the use of routine chemical analysis is adequate. Keywords: Model, restinga forest, Soil Quality Index (SQI).

  13. Little effects on soil organic matter chemistry of density fractions after seven years of forest soil warming.

    Science.gov (United States)

    Schnecker, Jörg; Borken, Werner; Schindlbacher, Andreas; Wanek, Wolfgang

    2016-12-01

    Rising temperatures enhance microbial decomposition of soil organic matter (SOM) and thereby increase the soil CO 2 efflux. Elevated decomposition rates might differently affect distinct SOM pools, depending on their stability and accessibility. Soil fractions derived from density fractionation have been suggested to represent SOM pools with different turnover times and stability against microbial decomposition. To investigate the effect of soil warming on functionally different soil organic matter pools, we here investigated the chemical and isotopic composition of bulk soil and three density fractions (free particulate organic matter, fPOM; occluded particulate organic matter, oPOM; and mineral associated organic matter, MaOM) of a C-rich soil from a long-term warming experiment in a spruce forest in the Austrian Alps. At the time of sampling, the soil in this experiment had been warmed during the snow-free period for seven consecutive years. During that time no thermal adaptation of the microbial community could be identified and CO 2 release from the soil continued to be elevated by the warming treatment. Our results, which included organic carbon content, total nitrogen content, δ 13 C, Δ 14 C, δ 15 N and the chemical composition, identified by pyrolysis-GC/MS, showed no significant differences in bulk soil between warming treatment and control. Surprisingly, the differences in the three density fractions were mostly small and the direction of warming induced change was variable with fraction and soil depth. Warming led to reduced N content in topsoil oPOM and subsoil fPOM and to reduced relative abundance of N-bearing compounds in subsoil MaOM. Further, warming increased the δ 13 C of MaOM at both sampling depths, reduced the relative abundance of carbohydrates while it increased the relative abundance of lignins in subsoil oPOM. As the size of the functionally different SOM pools did not significantly change, we assume that the few and small

  14. Do plant species influence soil CO2 and N2O fluxes in a diverse tropical forest?

    Science.gov (United States)

    J.L.M. van Haren; R.C. de Oliveira; N. Restrepo-Coupe; L. Hutyra; P. B. de Camargo; Michael Keller; S.R. Saleska

    2010-01-01

    [1] To test whether plant species influence greenhouse gas production in diverse ecosystems, we measured wet season soil CO2 and N2O fluxes close to 300 large (>35 cm in diameter at breast height (DBH)) trees of 15 species at three clay‐rich forest sites in central Amazonia. We found that soil CO2 fluxes were 38% higher near large trees than at control sites >10...

  15. Contributions of water supply from the weathered bedrock zone to forest soil quality

    Science.gov (United States)

    James H. Witty; Robert C. Graham; Kenneth R. Hubbert; James A. Doolittle; Jonathan A. Wald

    2003-01-01

    One measure of forest soil quality is the ability of the soil to support tree growth. In mediterranean-type ecosystems, such as most of California's forests, there is virtually no rainfall during the summer growing season, so trees must rely on water stored within the substrate. Water is the primary limitation to productivity in these forests. Many forest soils in...

  16. Soil solution and extractable soil nitrogen response to climate change in two boreal forest ecosystems

    NARCIS (Netherlands)

    Verburg, P.H.

    2005-01-01

    Several studies show that increases in soil temperature result in higher N mineralization rates in soils. It is, however, unclear if additional N is taken up by the vegetation or accumulates in the soil. To address this question two small, forested catchments in southern Norway were experimentally

  17. Methods of soil resampling to monitor changes in the chemical concentrations of forest soils

    Science.gov (United States)

    Gregory B. Lawrence; Ivan J. Fernandez; Paul W. Hazlett; Scott W. Bailey; Donald S. Ross; Thomas R. Villars; Angelica Quintana; Rock Ouimet; Michael R. McHale; Chris E. Johnson; Russell D. Briggs; Robert A. Colter; Jason Siemion; Olivia L. Bartlett; Olga Vargas; Michael R. Antidormi; Mary M. Koppers

    2016-01-01

    Recent soils research has shown that important chemical soil characteristics can change in less than a decade, often the result of broad environmental changes. Repeated sampling to monitor these changes in forest soils is a relatively new practice that is not well documented in the literature and has only recently been broadly embraced by the scientific community. The...

  18. [Mammals of Zoque Forest, Mexico: richness, use and conservation].

    Science.gov (United States)

    Lira-Torres, Iván; Galindo-Leal, Carlos; Briones-Salas, Miguel

    2012-06-01

    Zoque Forest is one of the richest and threatened regions in Southeastern Mexico, and for which few studies on mammal biology and use are available. Here we analyzed the conservation status of mammalian species according to Mexican and international laws, with an updated checklist of mammals in this forest, and some information on their use by some rural communities. Basic information was obtained from national and international collections and publications. A total of 42 fieldtrips, that followed conventional techniques, were conducted from 2003 through 2010, and some questionnaires to local hunters were applied. The mammalian fauna found in the area was composed of 149 species belonging to 99 genera and 30 families; these results support that the Zoque Forest is the richest in the number of mammalian species in Mexico. A total of 35 species were considered at risk by the Mexican National Law NOM-059-SEMARNAT-2010, and 21 species were found to be registered in the IUCN Red List or in CITES. Of the 40 species included in any of the lists, only the Baird's tapir, jaguar and white-lipped peccary were included in all three lists and 14 species were shared by the two of them. The main uses of mammals in order of importance are: 1) bushmeat, 2) pets, 3) skins, and 4) traditional medicine. Subsistence hunting and trade are unofficially allowed for farmers in this area. As for now, the region has healthy populations of a large number of mammals even though they have been used by local residents. However, since a considerable number of these species are listed under some criterion of threat, local authorities are called for more control.

  19. Soil-plant transfer factors in forest ecosystems

    International Nuclear Information System (INIS)

    Strebl, F.; Gerzabek, M.H.

    1995-04-01

    Within scope of an extended study about 137 Cs behaviour in forest ecosystems several parameters were found to influence soil-plant transfer factors. TF-values of different plant species cover a range of two magnitudes. This is partly due to variations in rooting depth of plants and specific physiological adaptations of nutrient supply. Perrenial plants like trees (Picea abies) and dwarf shrubs (Vaccinium myrtillus) showed a distinct age - dependency of 137 Cs - transfer factors. In young plant parts caesium concentration is higher than in old, more signified twigs. A correlation analysis of physico-chemical soil parameters and TF-values to forest vegetation showed, that soil organic matter, especially the degree of humification and the ratio between extractable fulvic to humic acids are important influencing factors of 137 Cs transfer from forest soils to plants. (author)

  20. Soil microbial community successional patterns during forest ecosystem restoration.

    Science.gov (United States)

    Banning, Natasha C; Gleeson, Deirdre B; Grigg, Andrew H; Grant, Carl D; Andersen, Gary L; Brodie, Eoin L; Murphy, D V

    2011-09-01

    Soil microbial community characterization is increasingly being used to determine the responses of soils to stress and disturbances and to assess ecosystem sustainability. However, there is little experimental evidence to indicate that predictable patterns in microbial community structure or composition occur during secondary succession or ecosystem restoration. This study utilized a chronosequence of developing jarrah (Eucalyptus marginata) forest ecosystems, rehabilitated after bauxite mining (up to 18 years old), to examine changes in soil bacterial and fungal community structures (by automated ribosomal intergenic spacer analysis [ARISA]) and changes in specific soil bacterial phyla by 16S rRNA gene microarray analysis. This study demonstrated that mining in these ecosystems significantly altered soil bacterial and fungal community structures. The hypothesis that the soil microbial community structures would become more similar to those of the surrounding nonmined forest with rehabilitation age was broadly supported by shifts in the bacterial but not the fungal community. Microarray analysis enabled the identification of clear successional trends in the bacterial community at the phylum level and supported the finding of an increase in similarity to nonmined forest soil with rehabilitation age. Changes in soil microbial community structure were significantly related to the size of the microbial biomass as well as numerous edaphic variables (including pH and C, N, and P nutrient concentrations). These findings suggest that soil bacterial community dynamics follow a pattern in developing ecosystems that may be predictable and can be conceptualized as providing an integrated assessment of numerous edaphic variables.

  1. Forest-to-pasture conversion increases the diversity of the phylum Verrucomicrobia in Amazon rainforest soils.

    Science.gov (United States)

    Ranjan, Kshitij; Paula, Fabiana S; Mueller, Rebecca C; Jesus, Ederson da C; Cenciani, Karina; Bohannan, Brendan J M; Nüsslein, Klaus; Rodrigues, Jorge L M

    2015-01-01

    The Amazon rainforest is well known for its rich plant and animal diversity, but its bacterial diversity is virtually unexplored. Due to ongoing and widespread deforestation followed by conversion to agriculture, there is an urgent need to quantify the soil biological diversity within this tropical ecosystem. Given the abundance of the phylum Verrucomicrobia in soils, we targeted this group to examine its response to forest-to-pasture conversion. Both taxonomic and phylogenetic diversities were higher for pasture in comparison to primary and secondary forests. The community composition of Verrucomicrobia in pasture soils was significantly different from those of forests, with a 11.6% increase in the number of sequences belonging to subphylum 3 and a proportional decrease in sequences belonging to the class Spartobacteria. Based on 99% operational taxonomic unit identity, 40% of the sequences have not been detected in previous studies, underscoring the limited knowledge regarding the diversity of microorganisms in tropical ecosystems. The abundance of Verrucomicrobia, measured with quantitative PCR, was strongly correlated with soil C content (r = 0.80, P = 0.0016), indicating their importance in metabolizing plant-derived carbon compounds in soils.

  2. Basidiomycete fungal communities in Australian sclerophyll forest soil are altered by repeated prescribed burning.

    Science.gov (United States)

    Anderson, Ian C; Bastias, Brigitte A; Genney, David R; Parkin, Pamela I; Cairney, John W G

    2007-04-01

    Soil basidiomycetes play key roles in forest nutrient and carbon cycling processes, yet the diversity and structure of below ground basidiomycete communities remain poorly understood. Prescribed burning is a commonly used forest management practice and there is evidence that single fire events can have an impact on soil fungal communities but little is known about the effects of repeated prescribed burning. We have used internal transcribed spacer (ITS) terminal restriction fragment length polymorphism (T-RFLP) analysis to investigate the impacts of repeated prescribed burning every two or four years over a period of 30 years on soil basidiomycete communities in an Australian wet sclerophyll forest. Detrended correspondence analysis of ITS T-RFLP profiles separated basidiomycete communities in unburned control plots from those in burned plots, with those burned every two years being the most different from controls. Burning had no effect on basidiomycete species richness, thus these differences appear to be due to changes in community structure. Basidiomycete communities in the unburned control plots were vertically stratified in the upper 20 cm of soil, but no evidence was found for stratification in the burned plots, suggesting that repeated prescribed burning results in more uniform basidiomycete communities. Overall, the results demonstrate that repeated prescribed burning alters soil basidiomycete communities, with the effect being greater with more frequent burning.

  3. Thermal Characteristics and Bacterial Diversity of Forest Soil in the Haean Basin of Korea

    OpenAIRE

    Kim, Heejung; Lee, Jin-Yong; Lee, Kang-Kun

    2014-01-01

    To predict biotic responses to disturbances in forest environments, it is important to examine both the thermophysical properties of forest soils and the diversity of microorganisms that these soils contain. To predict the effects of climate change on forests, in particular, it is essential to understand the interactions between the soil surface, the air, and the biological diversity in the soil. In this study, the temperature and thermal properties of forest soil at three depths at a site in...

  4. Soil organic matter regulates molybdenum storage and mobility in forests

    Science.gov (United States)

    Marks, Jade A; Perakis, Steven; King, Elizabeth K.; Pett-Ridge, Julie

    2015-01-01

    The trace element molybdenum (Mo) is essential to a suite of nitrogen (N) cycling processes in ecosystems, but there is limited information on its distribution within soils and relationship to plant and bedrock pools. We examined soil, bedrock, and plant Mo variation across 24 forests spanning wide soil pH gradients on both basaltic and sedimentary lithologies in the Oregon Coast Range. We found that the oxidizable organic fraction of surface mineral soil accounted for an average of 33 %of bulk soil Mo across all sites, followed by 1.4 % associated with reducible Fe, Al, and Mn-oxides, and 1.4 % in exchangeable ion form. Exchangeable Mo was greatest at low pH, and its positive correlation with soil carbon (C) suggests organic matter as the source of readily exchangeable Mo. Molybdenum accumulation integrated over soil profiles to 1 m depth (τMoNb) increased with soil C, indicating that soil organic matter regulates long-term Mo retention and loss from soil. Foliar Mo concentrations displayed no relationship with bulk soil Mo, and were not correlated with organic horizon Mo or soil extractable Mo, suggesting active plant regulation of Mo uptake and/or poor fidelity of extractable pools to bioavailability. We estimate from precipitation sampling that atmospheric deposition supplies, on average, over 10 times more Mo annually than does litterfall to soil. In contrast, bedrock lithology had negligible effects on foliar and soil Mo concentrations and on Mo distribution among soil fractions. We conclude that atmospheric inputs may be a significant source of Mo to forest ecosystems, and that strong Mo retention by soil organic matter limits ecosystem Mo loss via dissolution and leaching pathways.

  5. Managed forest landscape structure and avian species richness in the southeastern US

    Science.gov (United States)

    Craig Loehle; T. Bently Wigley; Scott Rutzmoser; John A. Gerwin; Patrick D. Keyser; Richard A. Lancia; Christopher J. Reynolds; Ronald E. Thill; Robert Weih; Don White; Petra Bohall Wood

    2005-01-01

    Forest structural features at the stand scale (e.g., snags, stem density, species composition) and habitat attributes at larger spatial scales (e.g., landscape pattern, road density) can influence biological diversity and have been proposed as indicators in sustainable forestry programs. This study investigated relationships between such factors and total richness of...

  6. Using synthetic polymers to reduce soil erosion after forest fires in Mediterranean soils

    Science.gov (United States)

    Lado, Marcos; Ben-Hur, Meni; Inbar, Assaf

    2010-05-01

    Forest fires are a major environmental problem in the Mediterranean region because they result in a loss of vegetation cover, changes in biodiversity, increases in greenhouse gasses emission and a potential increase of runoff and soil erosion. The large increases in runoff and sediment yields after high severity fires have been attributed to several factors, among them: increase in soil water repellency; soil sealing by detached particles and by ash particles, and the loss of a surface cover. The presence of a surface cover increases infiltration, and decreases runoff and erosion by several mechanisms which include: rainfall interception, plant evapotranspiration, preservation of soil structure by increasing soil organic matter, and increasing surface roughness. The loss of vegetation cover as a result of fire leaves the surface of the soil exposed to the direct impact of the raindrops, and therefore the sensitivity of the soil to runoff generation and soil loss increases. In this work, we propose a new method to protect soils against post-fire erosion based on the application of synthetic polymers to the soil. Laboratory rainfall simulations and field runoff plots were used to analyze the suitability of the application of synthetic polymers to reduce soil erosion and stabilize soil structure in Mediterranean soils. The combination of these two processes will potentially favor a faster recovery of the vegetation structure. This method has been successfully applied in arable land, however it has not been tested in burnt forests. The outcome of this study may provide important managerial tools for forest management following fires.

  7. Long term effects of ash recycling on soil and water chemistry in forests

    International Nuclear Information System (INIS)

    Westling, Olle; Kronnaes, Veronika

    2006-02-01

    IVL Swedish Environmental Research Institute has studied the long-term need of compensatory fertilisation (e.g. wood ash recycling) after whole tree harvest in coniferous forests in Sweden. The study is based on dynamic model calculations with scenarios including reduced atmospheric deposition of air pollutants and different intensity of forest management. The possibilities to counteract acidification in soil and water with application of stabilised wood ash are discussed. The reduction in deposition of acidifying air pollutants in Sweden up to 2010 is expected to contribute to a significant recovery from acidification in soil- and runoff water in forests. The recovery of the forest soil (e.g. base saturation ) will, however, be slow according to the model calculations, especially if compensatory fertilisation is not carried out in managed areas. The model calculations indicate that the harvest of stemwood will have limited impact on the future acidity of soil and run off water from well drained forest soils. This conclusion is based on a comparison with a scenario where no harvest is assumed. More important for recovery from acidification is further reduction of acidifying air pollutants, even after 2010. Harvest of stemwood in combination with extraction of harvest residues has the potential to cause significant and long term acidification of soils in the future, especially in areas with high forest production and slow weathering rate. The results of the study indicate a need of compensatory fertilisation in these areas if whole tree harvest is applied, especially if the deposition of air pollutants have been high in the past. Field studies have shown that acidification effects of whole tree harvest can be counteracted by wood ash recycling to forest soils, due to the high content of calcium- and magnesium-rich minerals in the ashes. However, the dose should be adjusted to the need of increasing the acid neutralising capacity in the soil and runoff and the actual

  8. Consistency of effects of tropical-forest disturbance on species composition and richness relative to use of indicator taxa.

    Science.gov (United States)

    Stork, N E; Srivastava, D S; Eggleton, P; Hodda, M; Lawson, G; Leakey, R R B; Watt, A D

    2017-08-01

    Lawton et al. (1998) found, in a highly cited study, that the species richness of 8 taxa each responds differently to anthropogenic disturbance in Cameroon forests. Recent developments in conservation science suggest that net number of species is an insensitive measure of change and that understanding which species are affected by disturbance is more important. It is also recognized that all disturbance types are not equal in their effect on species and that grouping species according to function rather than taxonomy is more informative of responses of biodiversity to change. In a reanalysis of most of the original Cameroon data set (canopy and ground ants, termites, canopy beetles, nematodes, and butterflies), we focused on changes in species and functional composition rather than richness and used a more inclusive measure of forest disturbance based on 4 component drivers of change: years since disturbance, tree cover, soil compaction, and degree of tree removal. Effects of disturbance on compositional change were largely concordant between taxa. Contrary to Lawton et al.'s findings, species richness for most groups did not decline with disturbance level, providing support for the view that trends in species richness at local scales do not reflect the resilience of ecosystems to disturbance. Disturbance affected species composition more strongly than species richness for butterflies, canopy beetles, and litter ants. For these groups, disturbance caused species replacements rather than just species loss. Only termites showed effects of disturbance on species richness but not composition, indicating species loss without replacement. Although disturbance generally caused changes in composition, the strength of this relationship depended on the disturbance driver. Butterflies, litter ants, and nematodes were correlated with amount of tree cover, canopy beetles were most strongly correlated with time since disturbance, and termites were most strongly correlated with

  9. Impacts of experimentally applied mountain biking and hiking on vegetation and soil of a deciduous forest.

    Science.gov (United States)

    Thurston, E; Reader, R J

    2001-03-01

    Many recent trail degradation problems have been attributed to mountain biking because of its alleged capacity to do more damage than other activities, particularly hiking. This study compared the effects of experimentally applied mountain biking and hiking on the understory vegetation and soil of a deciduous forest. Five different intensities of biking and hiking (i.e., 0, 25, 75, 200 and 500 passes) were applied to 4-m-long x 1-m-wide lanes in Boyne Valley Provincial Park, Ontario, Canada. Measurements of plant stem density, species richness, and soil exposure were made before treatment, two weeks after treatment, and again one year after treatment. Biking and hiking generally had similar effects on vegetation and soil. Two weeks after treatment, stem density and species richness were reduced by up to 100% of pretreatment values. In addition, the amount of soil exposed increased by up to 54%. One year later, these treatment effects were no longer detectable. These results indicate that at a similar intensity of activity, the short-term impacts of mountain biking and hiking may not differ greatly in the undisturbed area of a deciduous forest habitat. The immediate impacts of both activities can be severe but rapid recovery should be expected when the activities are not allowed to continue. Implications of these results for trail recreation are discussed.

  10. Measurement and characteristics of microbial biomass in forest soils

    International Nuclear Information System (INIS)

    Vance, E.D.

    1986-01-01

    The soil microbial biomass is the primary agent responsible for the breakdown and mineralization of soil organic matter and plays a major role in regulating nutrient availability to plants. In this study, methods for measuring biomass in soil were compared and tested in forest soils ranging in pH from 3.2 to 7.2. A good relationship between biomass C measured using the chloroform fumigation-incubation method and soil ATP or microbial biomass C by direct microscopy was found in soils at or above pH 4.2. The fumigation-incubation method consistently underestimated biomass C in soils below pH 4.2, however. Hypotheses for the breakdown of the fumigation-incubation method in strongly acid soils were tested by using an alterative fumigant, measuring the proportion of added 14 C labelled fungi and bacteria decomposed in fumigated soils (k/sub C/), and by studying the effect of large, non-fumigated soil inocula on the flush of respiration following fumigation. These studies indicated that the failure of the method in strongly acid soils was due to inhibited decomposition of non-microbial soil organic matter by the microbial recolonizing population following fumigation. A modified method for measuring biomass C by fumigation-incubation in acid soils is proposed

  11. Old-growth forests can accumulate carbon in soils

    Science.gov (United States)

    Zhou, G.; Liu, S.; Li, Z.; Zhang, Dongxiao; Tang, X.; Zhou, C.; Yan, J.; Mo, J.

    2006-01-01

    Old-growth forests have traditionally been considered negligible as carbon sinks because carbon uptake has been thought to be balanced by respiration. We show that the top 20-centimeter soil layer in preserved old-growth forests in southern China accumulated atmospheric carbon at an unexpectedly high average rate of 0.61 megagrams of carbon hectare-1 year-1 from 1979 to 2003. This study suggests that the carbon cycle processes in the belowground system of these forests are changing in response to the changing environment. The result directly challenges the prevailing belief in ecosystem ecology regarding carbon budget in old-growth forests and supports the establishment of a new, nonequilibrium conceptual framework to study soil carbon dynamics.

  12. Predicting spatial variations of tree species richness in tropical forests from high-resolution remote sensing.

    Science.gov (United States)

    Fricker, Geoffrey A; Wolf, Jeffrey A; Saatchi, Sassan S; Gillespie, Thomas W

    2015-10-01

    There is an increasing interest in identifying theories, empirical data sets, and remote-sensing metrics that can quantify tropical forest alpha diversity at a landscape scale. Quantifying patterns of tree species richness in the field is time consuming, especially in regions with over 100 tree species/ha. We examine species richness in a 50-ha plot in Barro Colorado Island in Panama and test if biophysical measurements of canopy reflectance from high-resolution satellite imagery and detailed vertical forest structure and topography from light detection and ranging (lidar) are associated with species richness across four tree size classes (>1, 1-10, >10, and >20 cm dbh) and three spatial scales (1, 0.25, and 0.04 ha). We use the 2010 tree inventory, including 204,757 individuals belonging to 301 species of freestanding woody plants or 166 ± 1.5 species/ha (mean ± SE), to compare with remote-sensing data. All remote-sensing metrics became less correlated with species richness as spatial resolution decreased from 1.0 ha to 0.04 ha and tree size increased from 1 cm to 20 cm dbh. When all stems with dbh > 1 cm in 1-ha plots were compared to remote-sensing metrics, standard deviation in canopy reflectance explained 13% of the variance in species richness. The standard deviations of canopy height and the topographic wetness index (TWI) derived from lidar were the best metrics to explain the spatial variance in species richness (15% and 24%, respectively). Using multiple regression models, we made predictions of species richness across Barro Colorado Island (BCI) at the 1-ha spatial scale for different tree size classes. We predicted variation in tree species richness among all plants (adjusted r² = 0.35) and trees with dbh > 10 cm (adjusted r² = 0.25). However, the best model results were for understory trees and shrubs (dbh 1-10 cm) (adjusted r² = 0.52) that comprise the majority of species richness in tropical forests. Our results indicate that high

  13. Soil Respiration of Three Mangrove Forests on Sanibel Island, Florida

    Science.gov (United States)

    Cartwright, F.; Bovard, B. D.

    2011-12-01

    Carbon cycling studies conducted in mangrove forests have typically focused on aboveground processes. Our understanding of carbon storage in these systems is therefore limited by the lack information on belowground processes such as fine root production and soil respiration. To our knowledge there exist no studies investigating temporal patterns in and environmental controls on soil respiration in multiple types of mangrove ecosystems concurrently. This study is part of a larger study on carbon storage in three mangrove forests on Sanibel Island, Florida. Here we report on eight months of soil respiration data within these forests that will ultimately be incorporated into an annual carbon budget for each habitat type. Soil respiration was monitored in the following three mangrove habitat types: a fringe mangrove forest dominated by Rhizophora mangle, a basin mangrove forest dominated by Avicennia germinans, and a higher elevation forest comprised of a mix of Avicennia germinans and Laguncularia racemosa, and non-woody salt marsh species. Beginning in June of 2010, we measured soil emissions of carbon dioxide at 5 random locations within three-100 m2 plots within each habitat type. Sampling was performed at monthly intervals and conducted over the course of three days. For each day, one plot from each habitat type was measured. In addition to soil respiration, soil temperature, salinity and gravimetric moisture content were also measured. Our data indicate the Black mangrove forest, dominated by Avicennia germinans, experiences the highest rates of soil respiration with a mean rate of 4.61 ± 0.60 μmol CO2 m-2 s-1. The mixed mangrove and salt marsh habitat has the lowest soil carbon emission rates with a mean of 2.78 ± 0.40 μmol CO2 m-2 s-1. Soil carbon effluxes appear to peak in the early part of the wet season around May to June and are lower and relatively constant the remainder of the year. Our data also suggest there are important but brief periods where

  14. Effects of forest conversion on soil microbial communities depend on soil layer on the eastern Tibetan Plateau of China.

    Directory of Open Access Journals (Sweden)

    Ruoyang He

    Full Text Available Forest land-use changes have long been suggested to profoundly affect soil microbial communities. However, how forest type conversion influences soil microbial properties remains unclear in Tibetan boreal forests. The aim of this study was to explore variations of soil microbial profiles in the surface organic layer and subsurface mineral soil among three contrasting forests (natural coniferous forest, NF; secondary birch forest, SF and spruce plantation, PT. Soil microbial biomass, activity and community structure of the two layers were investigated by chloroform fumigation, substrate respiration and phospholipid fatty acid analysis (PLFA, respectively. In the organic layer, both NF and SF exhibited higher soil nutrient levels (carbon, nitrogen and phosphorus, microbial biomass carbon and nitrogen, microbial respiration, PLFA contents as compared to PT. However, the measured parameters in the mineral soils often did not differ following forest type conversion. Irrespective of forest types, the microbial indexes generally were greater in the organic layer than in the mineral soil. PLFAs biomarkers were significantly correlated with soil substrate pools. Taken together, forest land-use change remarkably altered microbial community in the organic layer but often did not affect them in the mineral soil. The microbial responses to forest land-use change depend on soil layer, with organic horizons being more sensitive to forest conversion.

  15. Relative importance of current and past landscape structure and local habitat conditions for plant species richness in dry grassland-like forest openings.

    Science.gov (United States)

    Husáková, Iveta; Münzbergová, Zuzana

    2014-01-01

    In fragmented landscapes, plant species richness may depend not only on local habitat conditions but also on landscape structure. In addition, both present and past landscape structure may be important for species richness. There are, however, only a few studies that have investigated the relative importance of all of these factors. The aim of this study was to examine the effect of current and past landscape structures and habitat conditions on species richness at dry grassland-like forest openings in a forested landscape and to assess their relative importance for species richness. We analyzed information on past and present landscape structures using aerial photographs from 1938, 1973, 1988, 2000 and 2007. We calculated the area of each locality and its isolation in the present and in the past and the continuity of localities in GIS. At each locality, we recorded all vascular plant species (296 species in 110 forest openings) and information on abiotic conditions of the localities. We found that the current species richness of the forest openings was significantly determined by local habitat conditions as well as by landscape structure in the present and in the past. The highest species richness was observed on larger and more heterogeneous localities with rocks and shallow soils, which were already large and well connected to other localities in 1938. The changes in the landscape structure in the past can thus have strong effects on current species richness. Future studies attempting to understand determinants of species diversity in fragmented landscapes should also include data on past landscape structure, as it may in fact be more important than the present structure.

  16. Vertical zonation of soil fungal community structure in a Korean pine forest on Changbai Mountain, China.

    Science.gov (United States)

    Ping, Yuan; Han, Dongxue; Wang, Ning; Hu, Yanbo; Mu, Liqiang; Feng, Fujuan

    2017-01-01

    Changbai Mountain, with intact montane vertical vegetation belts, is located at a sensitive area of global climate change and a central distribution area of Korean pine forest. Broad-leaved Korean pine mixed forest (Pinus koraiensis as an edificator) is the most representative zonal climax vegetation in the humid region of northeastern China; their vertical zonation is the most intact and representative on Changbai Mountain. In this study, we analyzed the composition and diversity of soil fungal communities in the Korean pine forest on Changbai Mountain at elevations ranging from 699 to 1177 m using Illumina High-throughput sequencing. We obtained a total 186,663 optimized sequences, with an average length of 268.81 bp. We found soil fungal diversity index was decreased with increasing elevation from 699 to 937 m and began to rise after reaching 1044 m; the richness and evenness indices were decreased with an increase in elevation. Soil fungal compositions at the phylum, class and genus levels varied significantly at different elevations, but with the same dominant fungi. Beta-diversity analysis indicated that the similarity of fungal communities decreased with an increased vertical distance between the sample plots, showing a distance-decay relationship. Variation partition analysis showed that geographic distance (mainly elevation gradient) only explained 20.53 % of the total variation of fungal community structure, while soil physicochemical factors explained 69.78 %.

  17. Soil compaction during harvest operations in five tropical soils with different textures under eucalyptus forests

    Directory of Open Access Journals (Sweden)

    Paula Cristina Caruana Martins

    Full Text Available ABSTRACT Traffic of farm machinery during harvest and logging operations has been identified as the main source of soil structure degradation in forestry activity. Soil susceptibility to compaction and the amount of compaction caused by each forest harvest operation differs according to a number of factors (such as soil strength, soil texture, kind of equipment, traffic intensity, among many others, what requires the adequate assessment of soil compaction under different traffic conditions. The objectives of this study were to determine the susceptibility to compaction of five soil classes with different textures under eucalyptus forests based on their load bearing capacity models; and to determine, from these models and the precompression stresses obtained after harvest operations, the effect of traffic intensity with different equipment in the occurrence of soil compaction. Undisturbed soil samples were collected before and after harvest operations, being then subjected to uniaxial compression tests to determine their precompression stress. The coarse-textured soils were less resistant and endured greater soil compaction. In the clayey LVd2, traffic intensity below four Forwarder passes limited compaction to a third of the samples, whereas in the sandy loam PVd all samples from the 0-3 cm layer were compacted regardless of traffic intensity. The Feller Buncher and the Clambunk presented a high potential to cause soil compaction even with only one or two passes. The use of soil load bearing capacity models and precompression stress determined after harvest and logging operations allowed insight into the soil compaction process in forestry soils.

  18. [Effect of pine plantations on soil arthropods in a high Andean forest].

    Science.gov (United States)

    León-Gamboa, Alba Lucía; Ramos, Carolina; García, Mary Ruth

    2010-09-01

    One of the most common problems in the Colombian mountains has been the replacement of native vegetation by pine plantations. Soil arthropods are a fundamental component of forest ecosystem, since they participate in the organic matter fragmentation, previous to decomposition. This role is more valuable in high altitude environments, where low temperatures limit the dynamics of biological processes, where the effects of pine plantations on soil arthropods are still not well-known. In a remnant of high-andean forest (Neusa - Colombia) and a pine plantation of about 50 years-old, it was evaluated the composition, richness and abundance of arthropods at surface (S), organic horizon (O) and mineral horizon (A) of soil, to establish the differences associated to the soil use transformation. It was used "Pitfall" sampling to register the movement of the epigeous fauna, and extraction by funnel Berlese for determining the fauna density from O and A horizons. The Shannon and Simpson indexes estimated the diversity at different places and horizons, and the trophic structure of the community was evaluated. Overall, there were collected 38 306 individuals from forest and 17 386 individuals from pine plantation, mainly distributed in Collembola (42.4%), Acari (27%), Diptera (17.6%) and Coleoptera (4.6%). The most important differences were given in the surface, where the mobilization in forest (86 individuals/day) almost triplicates the one in pine plantation (33 individuals/day). The differences in composition were given in Collembola, Araneae, Hemiptera, Homoptera and Hymenoptera. The dynamics of richness and abundance along the year had significant high values in the native forest than in the pine plantation. The general trophic structure was dominated by saprophagous (75%), followed by predators (14%) and phytophagous (9%), but in two layers of the pine plantation soil (S and O) this structural pattern was not given. Based on the results, it was concluded that pine

  19. Sources of nitrous oxide emitted from European forest soils

    Directory of Open Access Journals (Sweden)

    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

  20. [Soil quality assessment of forest stand in different plantation esosystems].

    Science.gov (United States)

    Huang, Yu; Wang, Silong; Feng, Zongwei; Gao, Hong; Wang, Qingkui; Hu, Yalin; Yan, Shaokui

    2004-12-01

    After a clear-cutting of the first generation Cunninghamia lanceolata plantation in 1982, three plantation ecosystems, pure Michelia macclurei stand (PMS), pure Chinese-fir stand (PCS) and their mixed stand, were established in spring 1983, and their effects on soil characteristics were evaluated by measuring some soil physical, chemical, microbiological and biochemical parameters. After 20 years' plantation, all test indices showed differences among different forest management models. Both PMS and MCM had a favorable effect on soil fertility maintenance. Soil quality assessment showed that some soil functions, e.g., water availability, nutrient availability, root suitability and soil quality index were all in a moderate level under the mixed and pure PMS stands, whereas in a relatively lower level under successive PCS stand. The results also showed that there existed close correlations between soil total organic C (TOC), cation exchange capacity (CEC), microbial biomass-C (Cmic) and other soil physical, chemical and biological indices. Therefore, TOC, CEC and Cmic could be used as the indicators in assessing soil quality in this study area. In addition, there were also positive correlations between soil microbial biomass-C and TOC, soil microbial biomass-N and total N, and soil microbial biomass-P and total P in the present study.

  1. Land use, forest density, soil mapping, erosion, drainage, salinity limitations

    Science.gov (United States)

    Yassoglou, N. J. (Principal Investigator)

    1973-01-01

    The author has identified the following significant results. The results of analyses show that it is possible to obtain information of practical significance as follows: (1) A quick and accurate estimate of the proper use of the valuable land can be made on the basis of temporal and spectral characteristics of the land features. (2) A rather accurate delineation of the major forest formations in the test areas was achieved on the basis of spatial and spectral characteristics of the studied areas. The forest stands were separated into two density classes; dense forest, and broken forest. On the basis of ERTS-1 data and the existing ground truth information a rather accurate mapping of the major vegetational forms of the mountain ranges can be made. (3) Major soil formations are mapable from ERTS-1 data: recent alluvial soils; soil on quarternary deposits; severely eroded soil and lithosol; and wet soils. (4) An estimation of cost benefits cannot be made accurately at this stage of the investigation. However, a rough estimate of the ratio of the cost for obtaining the same amount information from ERTS-1 data and from conventional operations would be approximately 1:6 to 1:10, in favor of the ERTS-1.

  2. Sand and clay mineralogy of sal forest soils of the Doon Siwalik ...

    Indian Academy of Sciences (India)

    3Forest Soil & Land Reclamation Division, Forest Research Institute, Dehradun 248 006, India. ∗ e-mail: ... understanding the distribution of forest types and ... Material and methods. 2.1 Study area .... Finally, for the qualitative and quan-.

  3. Aggregate Stability in Soil with Humic and Histic Horizons in a Toposequence under Araucaria Forest

    Directory of Open Access Journals (Sweden)

    Daniel Hanke

    Full Text Available ABSTRACT Aggregate stability is one of the most important factors in soil conservation and maintenance of soil environmental functions. The objective of this study was to investigate the aggregate stability mechanisms related to chemical composition of organic matter in soil profiles with humic and histic horizons in a toposequence under Araucaria moist forest in southern Brazil. The soils sampled were classified as Humic Hapludox (highest position, Fluvaquentic Humaquepts (lowest slope position, and Typic Haplosaprists (floodplain. The C and N contents were determined in bulk soil samples. The chemical composition of soil organic matter was evaluated by infrared spectroscopy. Aggregate stability was determined by applying increasing levels of ultrasound energy. Carbon content increased from the top of the slope to the alluvial plain. Higher ultrasonic energy values for clay dispersion were observed in the C-rich soils in the lower landscape positions, indicating that organic compounds play an important role in the structural stabilization of these profiles. Both aliphatic and carbohydrate-like structures were pertinent to aggregate stability. In the Oxisol, organo-mineral interaction between carbohydrates and the clay mineral surface was the most important mechanism affecting aggregation. In soils with a higher C content (Humaquepts and Haplosaprists, stabilization is predominantly conferred by the aliphatic groups, which is probably due to the structural protection offered by these hydrophobic organic groups.

  4. Assessment of soil acidification effects on forest growth in Sweden

    International Nuclear Information System (INIS)

    Sverdrup, H.; Warfvinge, P.; Nihlgaard, B.

    1994-01-01

    The results of mapping critical loads, areas where they have been exceeded and steady state (Ca+Mg+K)/Al ratios of soils in Sweden, has been used to assess the order of magnitude of the ecological and economic risks involved with acid deposition for Swedish forests. The results of the calculations indicate that 81% of the Swedish forested area received acid deposition in excess of the critical load at present. Under continued deposition at 1990 level, forest die-back is predicted to occur on approximately 1% of the forested area, and significant growth rate reductions are predicted for 80% of the Swedish forested area. For Sweden, growth losses in the order of 17.5 million m -3 yr -1 are predicted, equivalent to approximately 19% of current growth. Comparable losses can be predicted for other Nordic countries. The soil acidification situation is predicted to deteriorate significantly during the next 5-15 years, unless rapid emission reductions can be achieved. A minimum deposition reduction over Sweden of 95% on sulphur deposition and 30% on the N deposition in relation to 1990 level is required in order to protect 95% of the Swedish forest ecosystems from adverse effects of acidification. A minimum reduction of 60% on sulphur deposition and 30% on the N deposition is required to keep forest harvest at planned levels. 148 refs., 9 figs., 9 tabs

  5. Forested landscapes promote richness and abundance of native bees (Hymenoptera: Apoidea: Anthophila) in Wisconsin apple orchards.

    Science.gov (United States)

    Watson, J C; Wolf, A T; Ascher, J S

    2011-06-01

    Wild bees provide vital pollination services for many native and agricultural plant species, yet the landscape conditions needed to support wild bee populations are not well understood or appreciated. We assessed the influence of landscape composition on bee abundance and species richness in apple (Malus spp.) orchards of northeastern Wisconsin during the spring flowering period. A diverse community of bee species occurs in these apple orchards, dominated by wild bees in the families Andrenidae and Halictidae and the honey bee, Apis mellifera L. Proportion of forest area in the surrounding landscape was a significant positive predictor of wild bee abundance in orchards, with strongest effects at a GIS (Geographic Information Systems) buffer distance of 1,000 m or greater. Forest area also was positively associated with species richness, showing strongest effects at a buffer distance of 2,000 m. Nonagricultural developed land (homes, lawns, etcetera) was significantly negatively associated with species richness at buffer distances >750 m and wild bee abundance in bowl traps at all distances. Other landscape variables statistically associated with species richness or abundance of wild bees included proportion area of pasture (positive) and proportion area of roads (negative). Forest area was not associated with honey bee abundance at any buffer distance. These results provide clear evidence that the landscape surrounding apple orchards, especially the proportion of forest area, affects richness and abundance of wild bees during the spring flowering period and should be a part of sustainable land management strategies in agro-ecosystems of northeastern Wisconsin and other apple growing regions.

  6. Emission and soil distribution of fumigants in forest tree nurseries

    Science.gov (United States)

    Dong Wang; Jennifer Juzwik; Stephen Fraedrich

    2005-01-01

    Production of tree seedlings in the majority of forest nurseries in the USA has relied on soil fumigation with methyl bromide (MeBr) to control soil-borne plant pathogens, weeds, parasitic nematodes and insects. Since the announcement of the scheduled MeBr phase-out, a number of nurseries throughout the United States have participated in research programs on MeBr...

  7. Charcoal Increases Microbial Activity in Eastern Sierra Nevada Forest Soils

    Directory of Open Access Journals (Sweden)

    Zachary W. Carter

    2018-02-01

    Full Text Available Fire is an important component of forests in the western United States. Not only are forests subjected to wildfires, but fire is also an important management tool to reduce fuels loads. Charcoal, a product of fire, can have major impacts on carbon (C and nitrogen (N cycling in forest soils, but it is unclear how these effects vary by dominant vegetation. In this study, soils collected from Jeffrey pine (JP or lodgepole pine (LP dominated areas and amended with charcoal derived from JP or LP were incubated to assess the importance of charcoal on microbial respiration and potential nitrification. In addition, polyphenol sorption was measured in unamended and charcoal-amended soils. In general, microbial respiration was highest at the 1% and 2.5% charcoal additions, but charcoal amendment had limited effects on potential nitrification rates throughout the incubation. Microbial respiration rates decreased but potential nitrification rates increased over time across most treatments. Increased microbial respiration may have been caused by priming of native organic matter rather than the decomposition of charcoal itself. Charcoal had a larger stimulatory effect on microbial respiration in LP soils than JP soils. Charcoal type had little effect on microbial processes, but polyphenol sorption was higher on LP-derived than JP-derived charcoal at higher amendment levels despite surface area being similar for both charcoal types. The results from our study suggest that the presence of charcoal can increase microbial activity in soils, but the exact mechanisms are still unclear.

  8. Soil changes in forest ecosystems: evidence for and probable causes

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, D W [Nevada Univ., Reno, NV (United States). Desert Research Inst. Nevada Univ., Reno, NV (US). Dept. of Range, Wildlife and Forestry; Cresser, M S [Aberdeen Univ. (GB). Dept. of Soil Science; Nilsson, S I [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Ecology and Environmental Research; Turner, John [New South Wales Forestry Commission, Sydney (AU). Wood Technology and Forest Research Div.; Ulrich, Bernhard [Goettingen Univ. (Germany). Inst. fuer Bodenkunde und Waldernaehrung; Binkley, Dan [Colorado State Univ., Fort Collins, CO (United States). Dept. of Forest and Wood Sciences; Cole, D W [Washington Univ., Seattle, WA (United States). Coll. of Forest Resources

    1990-01-01

    A review of the literature on forest soil change in North America, Central Europe, Sweden, U.K., and Australia reveals that changes are occurring in both polluted and unpolluted sites at a greater rate than previously suspected. Acid deposition has played a major role in recent acidification in some areas of Europe and, to a more limited extent, in Sweden and eastern North America. However, rapid rates of soil acidification are occurring in western North America and Australia due to internal processes such as tree uptake and nitrification associated with excessive nitrogen fixation. The presence of extremely acid soils is not necessarily an indicator of significant acidic deposition, as evidenced by their presence in unpolluted, even pristine forests of the north-western U.S.A. and Alaska. Numerous studies in Sweden, Australia, and North America show the important effects of tree uptake and harvesting upon soil acidification in managed forests. Furthermore, arguments can be presented that harvesting takes a greater toll upon the pools of potentially limiting cations than leaching. The rate at which soils are changing in some instances calls for re-evaluation of the budget analyses used to predict soil change. Specifically, inter-horizon changes due to uptake and recycling by vegetation, the interactions of such changes with naturally-and anthropogenically-produced acids, and the effects of aluminium uptake and recycling need further evaluation and study. (Author).

  9. The variations of aluminium species in mountainous forest soils and its implications to soil acidification.

    Science.gov (United States)

    Bradová, Monika; Tejnecký, Václav; Borůvka, Luboš; Němeček, Karel; Ash, Christopher; Šebek, Ondřej; Svoboda, Miroslav; Zenáhlíková, Jitka; Drábek, Ondřej

    2015-11-01

    Aluminium (Al) speciation is a characteristic that can be used as a tool for describing the soil acidification process. The question that was answered is how tree species (beech vs spruce) and type of soil horizon affect Al speciation. Our hypotesis is that spruce and beech forest vegetation are able to modify the chemical characteristics of organic horizon, hence the content of Al species. Moreover, these characteristics are seasonally dependent. To answer these questions, a detailed chromatographic speciation of Al in forest soils under contrasting tree species was performed. The Jizera Mountains area (Czech Republic) was chosen as a representative mountainous soil ecosystem. A basic forestry survey was performed on the investigated area. Soil and precipitation samples (throughfall, stemflow) were collected under both beech and spruce stands at monthly intervals from April to November during the years 2008-2011. Total aluminium content and Al speciation, pH, and dissolved organic carbon were determined in aqueous soil extracts and in precipitation samples. We found that the most important factors affecting the chemistry of soils, hence content of the Al species, are soil horizons and vegetation cover. pH strongly affects the amount of Al species under both forests. Fermentation (F) and humified (H) organic horizons contain a higher content of water extractable Al and Al(3+) compared to organo-mineral (A) and mineral horizons (B). With increasing soil profile depth, the amount of water extractable Al, Al(3+) and moisture decreases. The prevailing water-extractable species of Al in all studied soils and profiles under both spruce and beech forests were organically bound monovalent Al species. Distinct seasonal variations in organic and mineral soil horizons were found under both spruce and beech forests. Maximum concentrations of water-extractable Al and Al(3+) were determined in the summer, and the lowest in spring.

  10. Sand and clay mineralogy of sal forest soils of the Doon Siwalik ...

    Indian Academy of Sciences (India)

    3Forest Soil & Land Reclamation Division, Forest Research Institute, Dehradun 248 006, India. .... also helps in characterizing the soil mineralogical make-up in relation to the growth and develop- ment of the species essential for sustainable forest management. ...... and Weed S B (Madison: Soil Science Society of America).

  11. Associations between soil variables and vegetation structure and composition of Caribbean dry forests

    Science.gov (United States)

    Elvia M. Melendez-Ackerman; Julissa Rojas-Sandoval; Danny S. Fernandez; Grizelle Gonzalez; Hana Lopez; Jose Sustache; Mariely Morales; Miguel Garcia-Bermudez; Susan Aragon

    2016-01-01

    Soil–vegetation associations have been understudied in tropical dry forests when compared to the amount of extant research on this issue in tropical wet forests. Recent studies assert that vegetation in tropical dry forests is highly heterogeneous and that soil variability may be a contributing factor. In this study, we evaluated the relationship between soil variables...

  12. Soil carbon sequestration and changes in fungal and bacterial biomass following incorporation of forest residues

    Science.gov (United States)

    Matt D. Busse; Felipe G. Sanchez; Alice W. Ratcliff; John R. Butnor; Emily A. Carter; Robert F. Powers

    2009-01-01

    Sequestering carbon (C) in forest soils can benefit site fertility and help offset greenhouse gas emissions. However, identifying soil conditions and forest management practices which best promote C accumulation remains a challenging task. We tested whether soil incorporation of masticated woody residues alters short-term C storage at forested sites in western and...

  13. 137Cs in the fungal compartment of Swedish forest soils

    International Nuclear Information System (INIS)

    Vinichuk, Mykhaylo M.; Johanson, Karl J.; Taylor, Andy F.S.

    2004-01-01

    The 137 Cs activities in soil profiles and in the mycelia of four ectomycorrhizal fungi were studied in a Swedish forest in an attempt to understand the mechanisms governing the transfer and retention of 137 Cs in forest soil. The biomass of four species of fungi was determined and estimated to be 16 g m -2 in a peat soil and 47-189 g m -2 in non-peat soil to the depth of 10 cm. The vertical distribution was rather homogeneous for two species (Tylospora spp. and Piloderma fallax) and very superficial for Hydnellum peckii. Most of the 137 Cs activity in mycelium of non-peat soils was found in the upper 5 cm. Transfer factors were quite high even for those species producing resupinate sporocarps. In the peat soil only approximately 0.3% of the total 137 Cs inventory in soil was found in the fungal mycelium. The corresponding values for non-peat soil were 1.3, 1.8 and 1.9%

  14. Sewage sludge fertiliser use: implications for soil and plant copper evolution in forest and agronomic soils.

    Science.gov (United States)

    Ferreiro-Domínguez, Nuria; Rigueiro-Rodríguez, Antonio; Mosquera-Losada, M Rosa

    2012-05-01

    Fertilisation with sewage sludge may lead to crop toxicity and environmental degradation. This study aims to evaluate the effects of two types of soils (forest and agronomic), two types of vegetation (unsown (coming from soil seed bank) and sown), and two types of fertilisation (sludge fertilisation and mineral fertilisation, with a no fertiliser control) in afforested and treeless swards and in sown and unsown forestlands on the total and available Cu concentration in soil, the leaching of this element and the Cu levels in plant. The experimental design was completely randomised with nine treatments and three replicates. Fertilisation with sewage sludge increased the concentration of Cu in soil and plant, but the soil values never exceeded the maximum set by Spanish regulations. Sewage sludge inputs increased both the total and Mehlich 3 Cu concentrations in agronomic soils and the Cu levels in plant developed in agronomic and forest soils, with this effect pronounced in the unsown swards of forest soils. Therefore, the use of high quality sewage sludge as fertiliser may improve the global productivity of forest, agronomic and silvopastoral systems without creating environmental hazards. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Soil carbon and soil physical properties response to incorporating mulched forest slash

    Science.gov (United States)

    Felipe G. Sanchez; Emily A. Carter; John. F. Klepac

    2000-01-01

    A study was installed in the Lower Coastal Plain near Washington, NC, to test the hypothesis that incorporating organic matter in the form of comminuted forest slash would increase soil carbon and nutrient pools, and alter soil physical properties to favor pine growth. Two sites were selected, an organic and a mineral site, to compare the treatment effects on...

  16. Preliminary assessment of soil erosion impact during forest restoration process

    Science.gov (United States)

    Lai, Yen-Jen; Chang, Cheng-Sheng; Tsao, Tsung-Ming; Wey, Tsong-Huei; Chiang, Po-Neng; Wang, Ya-Nan

    2014-05-01

    Taiwan has a fragile geology and steep terrain. The 921 earthquake, Typhoon Toraji, Typhoon Morakot, and the exploitation and use of the woodland by local residents have severely damaged the landscape and posed more severe challenges to the montane ecosystem. A land conservation project has been implemented by the Experimental Forest of National Taiwan University which reclaimed approximately 1,500 hectares of leased woodland from 2008 to 2010, primarily used to grow bamboo, tea trees, betel nut, fruit, and vegetable and about 1,298 hectares have been reforested. The process of forest restoration involves clear cutting, soil preparation and a six-year weeding and tending period which may affect the amount of soil erosion dramatically. This study tried to assess the impact of forest restoration from the perspective of soil erosion through leased-land recovery periods and would like to benefit the practical implementation of reforestation in the future. A new plantation reforested in the early 2013 and a nearby 29-year-old mature forest were chosen as experimental and comparison sites. A self-designed weir was set up in a small watershed of each site for the runoff and sediment yield observation. According to the observed results from May to August 2013, a raining season in Taiwan, the runoff and erosion would not as high as we expected, because the in-situ soil texture of both sites is sandy loam to sandy with high percentage of coarse fragment which increased the infiltration. There were around 200 kg to 250 kg of wet sand/soil yielded in mature forest during the hit of Typhoon Soulik while the rest of the time only suspended material be yielded at both sites. To further investigate the influence of the six-year weeding and tending period, long term observations are needed for a more completed assessment of soil erosion impact.

  17. Litter type control on soil C and N stabilization dynamics in a temperate forest.

    Science.gov (United States)

    Hatton, Pierre-Joseph; Castanha, Cristina; Torn, Margaret S; Bird, Jeffrey A

    2015-03-01

    While plant litters are the main source of soil organic matter (SOM) in forests, the controllers and pathways to stable SOM formation remain unclear. Here, we address how litter type ((13) C/(15) N-labeled needles vs. fine roots) and placement-depth (O vs. A horizon) affect in situ C and N dynamics in a temperate forest soil after 5 years. Litter type rather than placement-depth controlled soil C and N retention after 5 years in situ, with belowground fine root inputs greatly enhancing soil C (x1.4) and N (x1.2) retention compared with aboveground needles. While the proportions of added needle and fine root-derived C and N recovered into stable SOM fractions were similar, they followed different transformation pathways into stable SOM fractions: fine root transfer was slower than for needles, but proportionally more of the remaining needle-derived C and N was transferred into stable SOM fractions. The stoichiometry of litter-derived C vs. N within individual SOM fractions revealed the presence at least two pools of different turnover times (per SOM fraction) and emphasized the role of N-rich compounds for long-term persistence. Finally, a regression approach suggested that models may underestimate soil C retention from litter with fast decomposition rates. © 2014 John Wiley & Sons Ltd.

  18. Pattern and dynamics of the ground vegetation in south Swedish Carpinus betulus forests. Importance of soil chemistry and management

    Energy Technology Data Exchange (ETDEWEB)

    Brunet, J. [Swedish Univ. of Agricultural Sciences, Dept. of Conservation Biology, Uppsala (Sweden); Falkengren-Grerup, U.; Tyler, G. [Plant Ecology, Dept. of Ecology, Lund (Sweden)

    1997-10-01

    The vegetation and environmental conditions of south Swedish horn-beam Carpinus betulus forests are described with data from 35 permanent sample plots. The main floristic gradient of the ground vegetation is closely related to acid-base properties of the top soil: Base saturation, pH and organic matter content. Other floristic differences are related to tree canopy cover and the distance of the sample plots to the Baltic coast. Species richness of herbaceous plants typical of forests increases with soil pH. The number of other herbaceous species, occurring in both forests and open habitats, and of woody species is not related to pH. Comparisons of vegetation data from 1983 and 1993 show relatively small compositional differences of the herbaceous forest flora. The number of other herbaceous species increased considerably in those plots where canopy trees had been cut after 1983. The number of new species in managed plots increases with soil pH. Species losses and gains of the herbaceous forest flora between 1983 and 1993 are generally lower as compared with other herbaceous species and woody species. However, the ground cover of herbaceous forest species, especially of Oxalis acetosella and Lamium galeobdolon, was considerably lower in 1993 as compared to 1983 in both unmanaged and managed plots. Possible explanations for this decrease are current soil acidification and drought during the growing season. (au) 32 refs.

  19. A Comparative Study of the Soil Fauna in forests and cultivated land on sandy soils in Suriname

    NARCIS (Netherlands)

    Drift, van der J.

    1963-01-01

    1. In the coastal area of Suriname the soil and surface fauna were studied in various types of agricultural land, and compared with the fauna in the adjacent forests. 2. In primeval forest the soil macroarthropods are less numerous than in secondary forest (Formicidae excluded). They range generally

  20. Relative nitrogen mineralization and nitrification potentials in relation to soil chemistry in oak forest soils along a historical deposition gradient

    Science.gov (United States)

    Ralph E. J. Boerner; Elaine Kennedy Sutherland

    1996-01-01

    This study quantified soil nutrient status and N mineralization/nitrification potentials in soils of oak-dominated, unmanaged forest stands in seven USDA Forest Service experimental forests (EF) ranging along a historical and current acidic deposition gradient from southern Illinois to central West Virginia.

  1. Forest soil mineral weathering rates: use of multiple approaches

    Science.gov (United States)

    Randy K. Kolka; D.F. Grigal; E.A. Nater

    1996-01-01

    Knowledge of rates of release of base cations from mineral dissolution (weathering) is essential to understand ecosystem elemental cycling. Although much studied, rates remain enigmatic. We compared the results of four methods to determine cation (Ca + Mg + K) release rates at five forested soils/sites in the northcentral U.S.A. Our premise was that multiple...

  2. Saturated hydraulic conductivity values of some forest soils of ...

    African Journals Online (AJOL)

    A simple falling-head method is presented for the laboratory determination of saturated hydraulic conductivity of some forest soils of Ghana. Using the procedure, it was found that saturated hydraulic conductivity was positively and negatively correlated with sand content and clay content, respectively, both at P = 0.05 level.

  3. Nitrate concentrations in soil solutions below Danish forests

    DEFF Research Database (Denmark)

    Callesen, Ingeborg; Raulund-Rasmussen, Karsten; Gundersen, Per

    1999-01-01

    leaching in relation to land-use, a national monitoring programme has established sampling routines in a 7x7 km grid including 111 points in forests. During winters of 1986-1993, soil samples were obtained from a depth of 0-25, 25-50, 50-75 and 75-100 cm. Nitrate concentrations in soil solutions were...... species. A few sites deviated radically from the general pattern of low concentrations. The elevated concentrations recorded there were probably caused by high levels of N deposition due to emission from local sources or temporal disruptions of the N cycle. The nitrate concentration in the soil solution...

  4. Resobio. Management of forest residues: preserving soils and biodiversity

    International Nuclear Information System (INIS)

    Rantien, Caroline; Charasse, Laurent; Wlerick, Lise; Landmann, Guy; Nivet, Cecile; Jallais, Anais; Augusto, Laurent; Bigot, Maryse; Thivolle Cazat, Alain; Bouget, Christophe; Brethes, Alain; Boulanger, Vincent; Richter, Claudine; Cornu, Sophie; Rakotoarison, Hanitra; Ulrich, Erwin; Deleuze, Christine; Michaud, Daniel; Cacot, Emmanuel; Pousse, Noemie; Ranger, Jacques; Saint-Andre, Laurent; Zeller, Bernd; Achat, David; Cabral, Anne-Sophie; Akroume, Emila; Aubert, Michael; Bailly, Alain; Fraysse, Jean-Yves; Fraud, Benoit; Gardette, Yves-Marie; Gibaud, Gwenaelle; Helou, Tammouz-Enaut; Pitocchi, Sophie; Vivancos, Caroline

    2014-03-01

    The Resobio project (management of forest slash: preservation of soils and biodiversity) aimed at updating knowledge available at the international level (with a focus on temperate areas) on the potential consequences of forest slash sampling on fertility and on biodiversity, and at identifying orientations for recommendations for a revision of the ADEME guide of 2006 on wise collecting of forest slash. The first part of this report is a synthesis report which gives an overview of results about twenty issues dealing with the nature of wood used for energy production and the role of slash, about the consequences of this type of collecting for soil fertility and species productivity, and about impacts on biodiversity. Based on these elements, recommendations are made for slash management and for additional follow-up and research. The second part contains five scientific and technical reports which more deeply analyse the issue of fertility, and technical documents on slash management (guides) published in various countries

  5. Carbon mineralisation in litter and soil organic matter in forests with different nitrogen status

    Energy Technology Data Exchange (ETDEWEB)

    Karlsson, Patrik

    2000-07-01

    The objective of this thesis was to investigate the effect of both organic and inorganic nitrogen (N) on carbon (C) mineralisation of litter and soil organic matter, in order to increase the understanding of factors affecting decomposition and, ultimately, soil C sequestration. Fresh recently fallen needle litter with three contrasting total N concentrations were sampled, along with litter, humus and mineral soil layers from coniferous and deciduous forest sites in Europe. The sampled substrates were incubated in the laboratory at constant temperature (15 deg C) and near-optimal moisture. The fresh needles further received additions of ammonium and nitrate. Initial C mineralisation rates were higher in fresh N-rich needles than in fresh N-poor needles. However, after a 559-day incubation at 15 deg C cumulative C mineralisation was lower in the fresh N-rich needles than in the fresh N-poor needles. Negative effects of high N on C mineralisation were also found in litter and humus layers in the European forests and at sites with N-fertilisation trials, where low C mineralisation rates were associated with high total N concentrations. During early stages of decomposition, addition of ammonium and nitrate to fresh needles did not increase cumulative C mineralisation, suggesting that the decomposing organisms were not limited by low N supply even in the low-N needles. The initially higher C mineralisation in N-rich compared with N-poor needles is suggested to be a consequence of higher C quality in the N-rich substrates. In later stages of decomposition, the question why N seemed to have a negative effect on decomposition could not be satisfactorily answered, although there were indications that recalcitrant N-containing compounds were formed in fresh needles with high N concentration. This thesis presents some probable explanations of the negative effect on decomposition of high N.

  6. The impact of nitrogen deposition on carbon sequestration in European forests and forest soils

    DEFF Research Database (Denmark)

    de Vries, Wim; Reinds, Gert Jan; Gundersen, Per

    2006-01-01

    for CO2 emissions because of harvest and forest fires, was assumed 33% of the overall C pool changes by growth. C sequestration in the soil were based on calculated nitrogen (N) retention (N deposition minus net N uptake minus N leaching) rates in soils, multiplied by the C/N ratio of the forest soils......An estimate of net carbon (C) pool changes and long-term C sequestration in trees and soils was made at more than 100 intensively monitored forest plots (level II plots) and scaled up to Europe based on data for more than 6000 forested plots in a systematic 16 km x 16 km grid (level I plots). C...... pool changes in trees at the level II plots were based on repeated forest growth surveys At the level I plots, an estimate of the mean annual C pool changes was derived from stand age and available site quality characteristics. C sequestration, being equal to the long-term C pool changes accounting...

  7. 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

  8. 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.

  9. Short-term effects of forest disturbances on soil nematode communities in European mountain spruce forests.

    Science.gov (United States)

    Čerevková, A; Renčo, M; Cagáň, L

    2013-09-01

    The nematode communities in spruce forests were compared with the short-term effects of forest damage, caused by windstorm, wildfire and management practices of forest soils. Soil samples were collected in June and October from 2006 to 2008 in four different sites: (1) forest unaffected by the wind (REF); (2) storm-felled forest with salvaged timber (EXT); (3) modified forest affected by timber salvage (wood removal) and forest fire (FIR); and (4) storm-felled forest where timber had been left unsalvaged (NEX). Nematode analysis showed that the dominant species in all four investigated sites were Acrobeloides nanus and Eudorylaimus silvaticus. An increase of A. nanus (35% of the total nematode abundance) in the first year in the FIR site led to the highest total abundance of nematodes compared with other sites, where nematode abundance reached the same level in the third year. In the FIR site bacterial feeders appeared to be the most representative trophic group, although in the second and third year, after disturbance, the abundance of this trophic group gradually decreased. In the NEX site, the number of nematode species, population densities and Maturity Index were similar to that recorded for the FIR site. In EXT and NEX sites, the other dominant species was the plant parasitic nematode Paratylenchus microdorus. Analyses of nematodes extracted from different forest soil samples showed that the highest number of species and diversity index for species (H'spp) were in the REF site. Differences between the nematode fauna in REF and other localities were clearly depicted by cluster analysis. The greatest Structure Index and Enrichment Index values were also in REF. In the EXT site, the number of nematode species, their abundance, H'spp and Maturity Index were not significantly different from those recorded in the reference site.

  10. Soil spore bank communities of ectomycorrhizal fungi in endangered Chinese Douglas-fir forests.

    Science.gov (United States)

    Wen, Zhugui; Shi, Liang; Tang, Yangze; Hong, Lizhou; Xue, Jiawang; Xing, Jincheng; Chen, Yahua; Nara, Kazuhide

    2018-01-01

    Chinese Douglas-fir (Pseudotsuga sinensis) is an endangered Pinaceae species found in several isolated regions of China. Although soil spore banks of ectomycorrhizal (ECM) fungi can play an important role in seedling establishment after disturbance, such as in the well-known North American relative (Pseudotsuga menziesii), we have no information about soil spore bank communities in relict forests of Chinese Douglas-fir. We conducted bioassays of 73 soil samples collected from three Chinese Douglas-fir forests, using North American Douglas-fir as bait seedlings, and identified 19 species of ECM fungi. The observed spore bank communities were significantly different from those found in ECM fungi on the roots of resident trees at the same sites (p = 0.02). The levels of potassium (K), nitrogen (N), organic matter, and the pH of soil were the dominant factors shaping spore bank community structure. A new Rhizopogon species was the most dominant species in the spore banks. Specifically, at a site on Sanqing Mountain, 22 of the 57 surviving bioassay seedlings (representing 21 of the 23 soil samples) were colonized by this species. ECM fungal richness significantly affected the growth of bioassay seedlings (R 2  = 0.20, p = 0.007). Growth was significantly improved in seedlings colonized by Rhizopogon or Meliniomyces species compared with uncolonized seedlings. Considering its specificity to Chinese Douglas-fir, predominance in the soil spore banks, and positive effect on host growth, this new Rhizopogon species could play critical roles in seedling establishment and forest regeneration of endangered Chinese Douglas-fir.

  11. Wild felid species richness affected by a corridor in the Lacandona forest, Mexico

    Directory of Open Access Journals (Sweden)

    Gil–Fernández, M.

    2017-02-01

    Full Text Available Wild felids are one of the most vulnerable species due to habitat loss caused by fragmentation of ecosystems. We analyzed the effect of a structural corridor, defined as a strip of vegetation connecting two habitat patches, on the richness and habitat occupancy of felids on three sites in Marqués de Comillas, Chiapas, one with two isolated forest patches, the second with a structural corridor, and the third inside the Montes Azules Biosphere Reserve. We found only two species (L. pardalis and H. yagouaroundi in the isolated forest patches, five species in the structural corridor, and four species inside the Reserve. The corridor did not significantly affect occupancy, but due to the low detection rates, further investigation is needed to rule out differences. Our results highlight the need to manage habitat connectivity in the remaining forests in order to preserve the felid community of Marqués de Comillas, Chiapas, México.

  12. Forest structure, diversity and soil properties in a dry tropical forest in Rajasthan, Western India

    OpenAIRE

    J. I. Nirmal Kumar,; Kanti Patel,; Rohit Bhoi Kumar

    2011-01-01

    Structure, species composition, and soil properties of a dry tropical forest in Rajasthan Western India, were examined by establishment of 25 plots. The forest was characterized by a relatively low canopy and a large number of small-diameter trees. Mean canopy height for this forest was 10 m and stands contained an average of 995 stems ha-1 (≥ 3.0 cm DBH); 52% of those stems were smaller than 10 cm DBH. The total basal area was 46.35 m2ha-1, of which Tectona grandis L. contributed 48%. The fo...

  13. Changes in diversity, biomass and abundance of soil macrofauna, Parrotio-Carpinetum forest at organic and semi-organic horizons

    Directory of Open Access Journals (Sweden)

    Masomeh Izadi

    2016-07-01

    Full Text Available Present study evaluates diversity, abundance and biomass of soil macrofauna in organic and semi-organic horizons in Parrotia persica-Carpinus betulus forest in Shast kola area. Totally 70 sample points were randomly selected from organic and semi-organic horizons then sampling was done by a rectangle 100 cm2 area. Soil macrofauna were separated from soil samples by hand sorting and using Berlese funnel then dried at 60°C for 72h and weighted in 0.001 gr. With using taxonomic classification key, thirteen macrofauna orders were identified. Most of abundance of soil macrofauna in both soil horizons were allocated to Millipedes order. Changes in diversity, abundance and biomass of macrofauna in both soil horizons were calculated. The results showed Shannon diversity index, Simpson evenness and Margalef richness indices in semi-organic horizon were more than organic horizon. Abundance and biomass of macrofauna in semi-organic horizon were more than organic horizon.

  14. Experimental soil warming effects on C, N, and major element cycling in a low elevation spruce-fir forest soil

    Science.gov (United States)

    Lindsey E. Rustad; Ivan J. Fernandez; Stephanie Arnold

    1996-01-01

    The effect of global warming on north temperate and boreal forest soils has been the subject of much recent debate. These soils serve as major reservoirs for C, N, and other nutrients necessary for forest growth and productivity. Given the uncertainties in estimates of organic matter turnover rates and storage, it is unclear whether these soils will serve as short or...

  15. Assessing soil quality: practicable standards for sustainable forest productivity in the United States

    Science.gov (United States)

    Robert F. Powers; Allan E. Tiarks; James R. Boyle

    1998-01-01

    Productive soils form the foundation for productive forests. But unfortunately, the significance of soil seems lost to modem society. Most of us are too far removed from the natural factors of production to appreciate the multiple roles of soil. Nor is its worth recognized well by many forest managers who too often see soil only in its capacity for logging roads and...

  16. Soil organic matter status in forest soils - possible indicators for climate change induced site shifts

    Science.gov (United States)

    Koch, Nadine; Thiele-Bruhn, Sören

    2010-05-01

    The quantity and quality of soil organic matter (SOM) and SOM pools and thus the soil properties related to carbon sequestration and water retention are not constant but exhibit considerable variation through changing climate. In total changes in soil fertility and an increase in plant stress are expected. This is relevant for northwest Europe as well and may have economic and social impacts since functions of forests for wood production, groundwater recharge, soil protection and recreation might be affected. The study is done by comparative investigation of selected sites at four watersheds that represent typical forest stands in the region of Luxembourg and South West Germany. The aim is to identify SOM storage and stability in forest soils and its dependence on site properties and interaction with tree stand conditions. According to state of the art fractionation schemes functional C pools in forest soils and their stabilization mechanisms are investigated. In particular, distribution patterns are determined depending on location, tree stand and climatic conditions. Aim is to identify characteristics of SOM stability through fractionation of SOM according to density, particle size and chemical extractability and their subsequent analytical characterization. So far, reasons about the origin, composition and stabilization mechanisms underlying the different SOM pools are not fully understood. Presented are different patterns of distribution of SOM in relation to land use and site conditions, as well as similarities and differences between the different forest soils and results in addition to passive OM pool, which is mainly responsible for long-term stabilization of carbon in soils. These are aligned with selected general' soil properties such as pH, CEC and texture.

  17. Observing and modeling links between soil moisture, microbes and CH4 fluxes from forest soils

    Science.gov (United States)

    Christiansen, Jesper; Levy-Booth, David; Barker, Jason; Prescott, Cindy; Grayston, Sue

    2017-04-01

    Soil moisture is a key driver of methane (CH4) fluxes in forest soils, both of the net uptake of atmospheric CH4 and emission from the soil. Climate and land use change will alter spatial patterns of soil moisture as well as temporal variability impacting the net CH4 exchange. The impact on the resultant net CH4 exchange however is linked to the underlying spatial and temporal distribution of the soil microbial communities involved in CH4 cycling as well as the response of the soil microbial community to environmental changes. Significant progress has been made to target specific CH4 consuming and producing soil organisms, which is invaluable in order to understand the microbial regulation of the CH4 cycle in forest soils. However, it is not clear as to which extent soil moisture shapes the structure, function and abundance of CH4 specific microorganisms and how this is linked to observed net CH4 exchange under contrasting soil moisture regimes. Here we report on the results from a research project aiming to understand how the CH4 net exchange is shaped by the interactive effects soil moisture and the spatial distribution CH4 consuming (methanotrophs) and producing (methanogens). We studied the growing season variations of in situ CH4 fluxes, microbial gene abundances of methanotrophs and methanogens, soil hydrology, and nutrient availability in three typical forest types across a soil moisture gradient in a temperate rainforest on the Canadian Pacific coast. Furthermore, we conducted laboratory experiments to determine whether the net CH4 exchange from hydrologically contrasting forest soils responded differently to changes in soil moisture. Lastly, we modelled the microbial mediation of net CH4 exchange along the soil moisture gradient using structural equation modeling. Our study shows that it is possible to link spatial patterns of in situ net exchange of CH4 to microbial abundance of CH4 consuming and producing organisms. We also show that the microbial

  18. A model for predicting embankment slope failures in clay-rich soils; A Louisiana example

    Science.gov (United States)

    Burns, S. F.

    2015-12-01

    A model for predicting embankment slope failures in clay-rich soils; A Louisiana example It is well known that smectite-rich soils significantly reduce the stability of slopes. The question is how much smectite in the soil causes slope failures. A study of over 100 sites in north and south Louisiana, USA, compared slopes that failed during a major El Nino winter (heavy rainfall) in 1982-1983 to similar slopes that did not fail. Soils in the slopes were tested for per cent clay, liquid limits, plasticity indices and semi-quantitative clay mineralogy. Slopes with the High Risk for failure (85-90% chance of failure in 8-15 years after construction) contained soils with a liquid limit > 54%, a plasticity index over 29%, and clay contents > 47%. Slopes with an Intermediate Risk (55-50% chance of failure in 8-15 years) contained soils with a liquid limit between 36-54%, plasticity index between 16-19%, and clay content between 32-47%. Slopes with a Low Risk chance of failure (soils with a liquid limit plasticity index soil characteristics before construction. If the soils fall into the Low Risk classification, construct the embankment normally. If the soils fall into the High Risk classification, one will need to use lime stabilization or heat treatments to prevent failures. Soils in the Intermediate Risk class will have to be evaluated on a case by case basis.

  19. Effects of Litter and Nutrient Additions on Soil Carbon Cycling in a Tropical Forest

    Science.gov (United States)

    Cusack, D. F.; Halterman, S.; Turner, B. L.; Tanner, E.; Wright, S. J.

    2014-12-01

    significantly smaller rapidly cycling C pools (1.8 ± 0.4 %, p < 0.05). These results demonstrate that changes in tropical forest NPP have high potential to alter the storage and cycling of C in C-rich soils, and that secondary fertilization effects are likely.

  20. Citizen Science for Urban Forest Management? Predicting the Data Density and Richness of Urban Forest Volunteered Geographic Information

    Directory of Open Access Journals (Sweden)

    Alec Foster

    2017-09-01

    Full Text Available Volunteered geographic information (VGI has been heralded as a promising new data source for urban planning and policymaking. However, there are also concerns surrounding uneven levels of participation and spatial coverage, despite the promotion of VGI as a means to increase access to geographic knowledge production. To begin addressing these concerns, this research examines the spatial distribution and data richness of urban forest VGI in Philadelphia, Pennsylvania and San Francisco, California. Using ordinary least squares (OLS, general linear models (GLM, and spatial autoregressive models, our findings reveal that sociodemographic and environmental indicators are strong predictors of both densities of attributed trees and data richness. Although recent digital urban tree inventory applications present significant opportunities for collaborative data gathering, innovative research, and improved policymaking, asymmetries in the quantity and quality of the data may undermine their effectiveness. If these incomplete and uneven datasets are used in policymaking, environmental justice issues may arise.

  1. The vulnerability of organic matter in Swiss forest soils

    Science.gov (United States)

    González Domínguez, Beatriz; Niklaus, Pascal A.; Studer, Mirjam S.; Hagedorn, Frank; Wacker, Lukas; Haghipour, Negar; Zimmermann, Stephan; Walthert, Lorenz; Abiven, Samuel; McIntyre, Cameron

    2017-04-01

    Soils contain more carbon than atmosphere and terrestrial vegetation combined [1], and thus are key players in the carbon cycle. With climate change, the soil organic carbon (SOC) pool is vulnerable to loss through increased CO2 emissions, which in turn can amplify changes with this carbon feedback [2]. The objective of this study is to investigate the variation of indicators of SOC vulnerability (e.g. SOC mineralisation, turnover time, bulk soil and mineralised 14C signatures) and to evaluate climate, soil and terrain variables as primary drivers. To choose the study locations we used a statistics-based approach to select a balanced combination of 54 forest sites with de-correlated drivers of SOC vulnerability (i.e. proxies for soil temperature and moisture, pH, % clay, slope gradient and orientation). Sites were selected from the forest soil database of the Swiss Federal Institute for Forest, Snow and Landscape Research (WSL), which in May 2014, contained data from 1,050 soil profiles spread across Switzerland. We re-sampled soils at the 54 locations during summer 2014. With these samples we run a standardized laboratory soil incubation (i.e. 25°C; soils moisture -20kPa; sieved to ≤ 2 mm; 40 g equivalent dry mass; adjusted to 0.8 g cm-3 bulk density) and measured SOC mineralisation on days 4, 13, 30, 63, 121 and 181 by trapping the CO2 evolved from soils in sodium hydroxide traps [3]. Additionally, we measured the 14C signature of the carbon trapped during last stage of the incubation, and compare it to the 14C signature of the bulk soil. Based on the cumulative SOC mineralised, we found that despite the well-studied relationship between climate and SOC dynamics [4], temperature did not emerge as a predictor of SOC vulnerability. In parallel, moisture only had a minor role, with soils from drier sites being the most vulnerable. This indicates a possible limitation of heterotrophic activity due to water shortage. On the other hand, soil pH raised as the driver

  2. Forest harvesting effects on soil temperature, moisture, and respiration in a bottomland hardwood forest

    International Nuclear Information System (INIS)

    Londo, A.J.; Messina, M.G.; Schoenholtz, S.H.

    1999-01-01

    The effect of forest disturbance on C cycling has become an issue, given concerns about escalating atmospheric C content. The authors examined the effects of harvest intensity on in situ and laboratory mineral soil respiration in an East Texas bottomland hardwood forest between 6 and 22 mo after harvesting. Treatments included a clearcut, a partial cut wherein approximately 58% of the basal area was removed, and an unharvested control. The soda-lime absorption technique was used for in situ respiration (CO 2 efflux) and the wet alkali method (NaOH) was used for laboratory mineral soil respiration. Soil temperature and moisture content were also measured. Harvesting significantly increased in situ respiration during most sampling periods. This effect was attributed to an increase in live root and microflora activity associated with postharvesting revegetation. In situ respiration increased exponentially (Q 10 relationship) as treatment soil temperatures increased, but followed a parabolic-type pattern through the range of soil moisture measured (mean range 10.4--31.5%). Mean rates of laboratory mineral soil respiration measured during the study were unaffected by cutting treatment for most sampling sessions. Overall, the mean rate of CO 2 efflux in the clearcuts was significantly higher than that in the partial cuts, which in turn was significantly higher than that in the controls. Mass balance estimates indicate that these treatment differences will have little or no long-term effect on C sequestration of these managed forests

  3. Soil C and N storage and microbial biomass in US southern pine forests: Influence of forest management

    Science.gov (United States)

    J.A. Foote; T.W. Boutton; D.A. Scott

    2015-01-01

    Land management practices have strong potential to modify the biogeochemistry of forest soils, with implications for the long-term sustainability and productivity of forestlands. The Long-Term Soil Productivity (LTSP) program, a network of 62 sites across the USA and Canada, was initiated to address concerns over possible losses of soil productivity due to soil...

  4. Soil Stabilization with Lime for the Construction of Forest Roads

    Directory of Open Access Journals (Sweden)

    Reginaldo Sérgio Pereira

    2018-02-01

    Full Text Available ABSTRACT The mechanical performance of soil stabilization using lime to improve forest roads was assessed. This study was conducted with lateritic soil (LVAd30 using lime content of 2% in the municipality of Niquelândia, Goiás state, Brazil. Geotechnical tests of soil characterization, compaction, and mechanical strength were performed applying different compaction efforts and curing periods. The results showed that lime content significantly changed the mechanical performance of natural soil, increasing its mechanical strength and load-carrying capacity. Compaction effort and curing time provided different responses in the unconfined compressive strength (UCS and California Bearing Ratio (CBR tests. The best UCS value (786.59 kPa for the soil-lime mixture was achieved with modified compaction effort and curing time of 28 days. In the CBR test, soil-lime mixtures compacted at intermediate and modified efforts and cured for 28 days were considered for application as subbase material of flexible road pavements, being a promising alternative for use in layers of forest roads.

  5. Natural and artificial radionuclides in forest and bog soils: tracers for migration processes and soil development

    International Nuclear Information System (INIS)

    Schleich, N.; Degering, D.; Unterricker, S.

    2000-01-01

    Radionuclide distributions in undisturbed forest and bog soils, mostly situated in Saxony, Germany (Erzgebirge), were studied. Low concentrations of naturally-occurring U and Th decay series nuclides, including 210 Pb, and artificial radioisotopes ( 125 Sb, 134 Cs, 137 Cs, 241 Am) were determined using low-level γ-spectrometry. In addition, the activities of 238 Pu and 239,240 Pu were determined by radiochemical separation and α-spectrometry. 14 C and excess 210 Pb dating methods were used to date the sampled bog profiles. The different radionuclides show characteristic depth distributions in the forest and bog soil horizons, which were sub-sampled as thin slices. 125 Sb, 241 Am, 238 Pu and 239,240 Pu are strongly fixed in soil organic matter. In spruce forest soils, the influence of soil horizons with distinct properties dominates the vertical time-dependent distribution. In ombrotrophic bogs, the peak positions correlated with the year of maximum input of each nuclide. The Sb, Am and Pu ''time markers'' and the 14 C and 210 Pb dating results correspond very well. Although Cs seems to be relatively mobile in organic as well as mineral forest soil horizons, it is enriched in the organic material. In ombrotrophic bogs, Cs is very mobile in the peat deposit. In Sphagnum peat, Cs is translocated continuously towards the growing apices of the Sphagnum mosses, where it is accumulated. (orig.)

  6. Bryophyte-dominated biological soil crusts mitigate soil erosion in an early successional Chinese subtropical forest

    Directory of Open Access Journals (Sweden)

    S. Seitz

    2017-12-01

    Full Text Available This study investigated the development of biological soil crusts (biocrusts in an early successional subtropical forest plantation and their impact on soil erosion. Within a biodiversity and ecosystem functioning experiment in southeast China (biodiversity and ecosystem functioning (BEF China, the effect of these biocrusts on sediment delivery and runoff was assessed within micro-scale runoff plots under natural rainfall, and biocrust cover was surveyed over a 5-year period. Results showed that biocrusts occurred widely in the experimental forest ecosystem and developed from initial light cyanobacteria- and algae-dominated crusts to later-stage bryophyte-dominated crusts within only 3 years. Biocrust cover was still increasing after 6 years of tree growth. Within later-stage crusts, 25 bryophyte species were determined. Surrounding vegetation cover and terrain attributes significantly influenced the development of biocrusts. Besides high crown cover and leaf area index, the development of biocrusts was favoured by low slope gradients, slope orientations towards the incident sunlight and the altitude of the research plots. Measurements showed that bryophyte-dominated biocrusts strongly decreased soil erosion, being more effective than abiotic soil surface cover. Hence, their significant role in mitigating sediment delivery and runoff generation in mesic forest environments and their ability to quickly colonise soil surfaces after disturbance are of particular interest for soil erosion control in early-stage forest plantations.

  7. Bryophyte-dominated biological soil crusts mitigate soil erosion in an early successional Chinese subtropical forest

    Science.gov (United States)

    Seitz, Steffen; Nebel, Martin; Goebes, Philipp; Käppeler, Kathrin; Schmidt, Karsten; Shi, Xuezheng; Song, Zhengshan; Webber, Carla L.; Weber, Bettina; Scholten, Thomas

    2017-12-01

    This study investigated the development of biological soil crusts (biocrusts) in an early successional subtropical forest plantation and their impact on soil erosion. Within a biodiversity and ecosystem functioning experiment in southeast China (biodiversity and ecosystem functioning (BEF) China), the effect of these biocrusts on sediment delivery and runoff was assessed within micro-scale runoff plots under natural rainfall, and biocrust cover was surveyed over a 5-year period. Results showed that biocrusts occurred widely in the experimental forest ecosystem and developed from initial light cyanobacteria- and algae-dominated crusts to later-stage bryophyte-dominated crusts within only 3 years. Biocrust cover was still increasing after 6 years of tree growth. Within later-stage crusts, 25 bryophyte species were determined. Surrounding vegetation cover and terrain attributes significantly influenced the development of biocrusts. Besides high crown cover and leaf area index, the development of biocrusts was favoured by low slope gradients, slope orientations towards the incident sunlight and the altitude of the research plots. Measurements showed that bryophyte-dominated biocrusts strongly decreased soil erosion, being more effective than abiotic soil surface cover. Hence, their significant role in mitigating sediment delivery and runoff generation in mesic forest environments and their ability to quickly colonise soil surfaces after disturbance are of particular interest for soil erosion control in early-stage forest plantations.

  8. Characterization of soil fauna under the influence of mercury atmospheric deposition in Atlantic Forest, Rio de Janeiro, Brazil.

    Science.gov (United States)

    Buch, Andressa Cristhy; Correia, Maria Elizabeth Fernandes; Teixeira, Daniel Cabral; Silva-Filho, Emmanoel Vieira

    2015-06-01

    The increasing levels of mercury (Hg) found in the atmosphere arising from anthropogenic sources, have been the object of great concern in the past two decades in industrialized countries. Brazil is the seventh country with the highest rate of mercury in the atmosphere. The major input of Hg to ecosystems is through atmospheric deposition (wet and dry), being transported in the atmosphere over large distances. The forest biomes are of strong importance in the atmosphere/soil cycling of elemental Hg through foliar uptake and subsequent transference to the soil through litter, playing an important role as sink of this element. Soil microarthropods are keys to understanding the soil ecosystem, and for such purpose were characterized by the soil fauna of two Units of Forest Conservation of the state of the Rio de Janeiro, inwhich one of the areas suffer quite interference from petrochemicals and industrial anthropogenic activities and other area almost exempts of these perturbations. The results showed that soil and litter of the Atlantic Forest in Brazil tend to stock high mercury concentrations, which could affect the abundance and richness of soil fauna, endangering its biodiversity and thereby the functioning of ecosystems. Copyright © 2015. Published by Elsevier B.V.

  9. Species richness and structure of an anuran community in an Atlantic Forest site in southern Brazil

    Directory of Open Access Journals (Sweden)

    Adriele Karlokoski Cunha

    2010-06-01

    Full Text Available The species richness and spatial distribution of an anuran community were studied over 12 months in an Atlantic Forest area in São José dos Pinhais Municipality, Paraná State, southern Brazil. During field surveys, we registered 32 species from ten families: Brachycephalidae (2, Bufonidae (2, Centrolenidae (1, Cycloramphidae (1, Hemiphractidae (1, Hylidae (18, Hylodidae (1, Leiuperidae (2, Leptodactylidae (3, and Microhylidae (1. Sixteen species were registered in open areas, while seventeen species were found on forest borders and twenty species in forest areas. In relation to the microhabitat utilization, species were registered according to stratum of vocalization: 1 on the ground (eight; 2 in the water (two; 3 in the lower stratum (eleven; 4 in the intermediate stratum (five; 5 in the upper stratum (four. Five species were abundant (15.6%, while twelve were common (37.5%, and fifteen were considered rare (46.9%. The biological aspects of the majority of the species described in this work as related to forest areas are not well known. This fact reinforces the importance of Atlantic Forest conservation.

  10. Biochemical parameters and bacterial species richness in soils contaminated by sludge-borne metals and remediated with inorganic soil amendments

    International Nuclear Information System (INIS)

    Mench, Michel; Renella, Giancarlo; Gelsomino, Antonio; Landi, Loretta; Nannipieri, Paolo

    2006-01-01

    The effectiveness of two amendments for the in situ remediation of a Cd- and Ni-contaminated soil in the Louis Fargue long-term field experiment was assessed. In April 1995, one replicate plot (S1) was amended with 5% w/w of beringite (B), a coal fly ash (treatment S1 + B), and a second plot with 1% w/w zerovalent-Fe iron grit (SS) (treatment S1+SS), with the aim of increasing metal sorption and attenuating metal impacts. Long-term responses of daily respiration rates, microbial biomass, bacterial species richness and the activities of key soil enzymes (acid and alkaline phosphatase, arylsulfatase, β-glucosidase, urease and protease activities) were studied in relation to soil metal extractability. Seven years after initial amendments, the labile fractions of Cd and Ni in both the S1 + B and S1 + SS soils were reduced to various extents depending on the metal and fractions considered. The soil microbial biomass and respiration rate were not affected by metal contamination and amendments in the S1 + B and S1 + SS soils, whereas the activity of different soil enzymes was restored. The SS treatment was more effective in reducing labile pools of Cd and Ni and led to a greater recovery of soil enzyme activities than the B treatment. Bacterial species richness in the S1 soil did not alter with either treatment. It was concluded that monitoring of the composition and activity of the soil microbial community is important in evaluating the effectiveness of soil remediation practices. - Amendments (coal fly ash, zerovalent-Fe iron grit), reduced labile fractions of Cd and Ni in contaminated soils and restored the activity of key soil hydrolases

  11. Carbon Cycling in Wetland Forest Soils

    Science.gov (United States)

    Carl C. Trettin; Martin F. Jurgensen

    2003-01-01

    Wetlands comprise a small proportion (i.e., 2 to 3%) of earth's terrestrial surface, yet they contain a significant proportion of the terrestrial carbon (C) pool. Soils comprise the largest terrestrial C pool (ca. 1550 Pg C in upper 100 cm; Eswaran et al., 1993; Batjes, 1996), and wetlands contain the single largest component, with estimates ranging between 18...

  12. Magnetic study of weakly contaminated forest soils

    Czech Academy of Sciences Publication Activity Database

    Kapička, Aleš; Jordanova, Neli; Petrovský, Eduard; Podrázský, V.

    2003-01-01

    Roč. 148, 1/4 (2003), s. 31-44 ISSN 0049-6979 R&D Projects: GA AV ČR IAA3012905 Institutional research plan: CEZ:AV0Z3012916 Keywords : anthropogenic ferrimagnetics * environmental magnetism * soil pollution Subject RIV: DE - Earth Magnetism, Geodesy, Geography Impact factor: 0.883, year: 2003

  13. Value of Old Forest Attributes Related to Cryptogam Species Richness in Temperate Forests: A Quantitative Assessment

    Czech Academy of Sciences Publication Activity Database

    Hofmeister, J.; Hošek, J.; Brabec, Marek; Dvořák, D.; Beran, M.; Deckerová, H.; Burel, J.; Kříž, M.; Borovička, Jan; Běťák, J.; Vašutová, M.; Malíček, J.; Palice, Zdeněk; Syrovátková, L.; Steinová, J.; Černajová, I.; Holá, E.; Novozámská, E.; Čížek, L.; Iarema, V.; Baltaziuk, K.; Svoboda, T.

    2015-01-01

    Roč. 57, October (2015), s. 497-504 ISSN 1470-160X Grant - others:GA MŽP(CZ) SP/2D1/146/08 Institutional support: RVO:67985807 ; RVO:67985831 ; RVO:67985939 Keywords : Bryophytes * Dead wood * Forest structure * Lichens * Macrofungi * Size-dependent coefficient model Subject RIV: BB - Applied Statistics, Operational Research; EF - Botanics (BU-J); EF - Botanics (GLU-S) Impact factor: 3.190, year: 2015

  14. Tropical forest soil microbial communities couple iron and carbon biogeochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Dubinsky, E.A.; Silver, W.L.; Firestone, M.K.

    2009-10-15

    We report that iron-reducing bacteria are primary mediators of anaerobic carbon oxidation in upland tropical soils spanning a rainfall gradient (3500 - 5000 mm yr-1) in northeast Puerto Rico. The abundant rainfall and high net primary productivity of these tropical forests provide optimal soil habitat for iron-reducing and iron-oxidizing bacteria. Spatially and temporally dynamic redox conditions make iron-transforming microbial communities central to the belowground carbon cycle in these wet tropical forests. The exceedingly high abundance of iron-reducing bacteria (up to 1.2 x 10{sup 9} cells per gram soil) indicated that they possess extensive metabolic capacity to catalyze the reduction of iron minerals. In soils from the higher rainfall sites, measured rates of ferric iron reduction could account for up to 44 % of organic carbon oxidation. Iron reducers appeared to compete with methanogens when labile carbon availability was limited. We found large numbers of bacteria that oxidize reduced iron at sites with high rates of iron reduction and large numbers of iron-reducers. the coexistence of large populations of ironreducing and iron-oxidizing bacteria is evidence for rapid iron cycling between its reduced and oxidized states, and suggests that mutualistic interactions among these bacteria ultimately fuel organic carbon oxidation and inhibit CH4 production in these upland tropical forests.

  15. Methods of soil resampling to monitor changes in the chemical concentrations of forest soils

    Science.gov (United States)

    Lawrence, Gregory B.; Fernandez, Ivan J.; Hazlett, Paul W.; Bailey, Scott W.; Ross, Donald S.; Villars, Thomas R.; Quintana, Angelica; Ouimet, Rock; McHale, Michael; Johnson, Chris E.; Briggs, Russell D.; Colter, Robert A.; Siemion, Jason; Bartlett, Olivia L.; Vargas, Olga; Antidormi, Michael; Koppers, Mary Margaret

    2016-01-01

    Recent soils research has shown that important chemical soil characteristics can change in less than a decade, often the result of broad environmental changes. Repeated sampling to monitor these changes in forest soils is a relatively new practice that is not well documented in the literature and has only recently been broadly embraced by the scientific community. The objective of this protocol is therefore to synthesize the latest information on methods of soil resampling in a format that can be used to design and implement a soil monitoring program. Successful monitoring of forest soils requires that a study unit be defined within an area of forested land that can be characterized with replicate sampling locations. A resampling interval of 5 years is recommended, but if monitoring is done to evaluate a specific environmental driver, the rate of change expected in that driver should be taken into consideration. Here, we show that the sampling of the profile can be done by horizon where boundaries can be clearly identified and horizons are sufficiently thick to remove soil without contamination from horizons above or below. Otherwise, sampling can be done by depth interval. Archiving of sample for future reanalysis is a key step in avoiding analytical bias and providing the opportunity for additional analyses as new questions arise.

  16. Methods of Soil Resampling to Monitor Changes in the Chemical Concentrations of Forest Soils.

    Science.gov (United States)

    Lawrence, Gregory B; Fernandez, Ivan J; Hazlett, Paul W; Bailey, Scott W; Ross, Donald S; Villars, Thomas R; Quintana, Angelica; Ouimet, Rock; McHale, Michael R; Johnson, Chris E; Briggs, Russell D; Colter, Robert A; Siemion, Jason; Bartlett, Olivia L; Vargas, Olga; Antidormi, Michael R; Koppers, Mary M

    2016-11-25

    Recent soils research has shown that important chemical soil characteristics can change in less than a decade, often the result of broad environmental changes. Repeated sampling to monitor these changes in forest soils is a relatively new practice that is not well documented in the literature and has only recently been broadly embraced by the scientific community. The objective of this protocol is therefore to synthesize the latest information on methods of soil resampling in a format that can be used to design and implement a soil monitoring program. Successful monitoring of forest soils requires that a study unit be defined within an area of forested land that can be characterized with replicate sampling locations. A resampling interval of 5 years is recommended, but if monitoring is done to evaluate a specific environmental driver, the rate of change expected in that driver should be taken into consideration. Here, we show that the sampling of the profile can be done by horizon where boundaries can be clearly identified and horizons are sufficiently thick to remove soil without contamination from horizons above or below. Otherwise, sampling can be done by depth interval. Archiving of sample for future reanalysis is a key step in avoiding analytical bias and providing the opportunity for additional analyses as new questions arise.

  17. Natural and artificial radioactivity in soils of forests

    International Nuclear Information System (INIS)

    Alvarado, E.; Segovia, N.; Gaso P, M.I.; Pena, P.; Morton, O.; Armienta, M.A.

    2001-01-01

    Levels of 222 Rn, 40 K, 235 U, 226 Ra and 137 Cs were studied in soils of a forest zone located at 3000 m altitude in the central portion of Mexico. the radon concentrations in different soil horizons were determined with solid state nuclear track detectors and the concentrations of 40 K, 235 U, 226 Ra and 137 Cs in soil samples were measured with a gamma spectrometer at low level coupled to a High purity Ge detector. The results indicate differences of a magnitude order in the radon concentrations inside the studied area. The levels of 40 K, 235 U, 226 Ra and 137 Cs are discussed as function of the perturbation grade of the soil and atmospheric pollution. (Author)

  18. Using advanced surface complexation models for modelling soil chemistry under forests: Solling forest, Germany

    International Nuclear Information System (INIS)

    Bonten, Luc T.C.; Groenenberg, Jan E.; Meesenburg, Henning; Vries, Wim de

    2011-01-01

    Various dynamic soil chemistry models have been developed to gain insight into impacts of atmospheric deposition of sulphur, nitrogen and other elements on soil and soil solution chemistry. Sorption parameters for anions and cations are generally calibrated for each site, which hampers extrapolation in space and time. On the other hand, recently developed surface complexation models (SCMs) have been successful in predicting ion sorption for static systems using generic parameter sets. This study reports the inclusion of an assemblage of these SCMs in the dynamic soil chemistry model SMARTml and applies this model to a spruce forest site in Solling Germany. Parameters for SCMs were taken from generic datasets and not calibrated. Nevertheless, modelling results for major elements matched observations well. Further, trace metals were included in the model, also using the existing framework of SCMs. The model predicted sorption for most trace elements well. - Highlights: → Surface complexation models can be well applied in field studies. → Soil chemistry under a forest site is adequately modelled using generic parameters. → The model is easily extended with extra elements within the existing framework. → Surface complexation models can show the linkages between major soil chemistry and trace element behaviour. - Surface complexation models with generic parameters make calibration of sorption superfluous in dynamic modelling of deposition impacts on soil chemistry under nature areas.

  19. Using advanced surface complexation models for modelling soil chemistry under forests: Solling forest, Germany

    Energy Technology Data Exchange (ETDEWEB)

    Bonten, Luc T.C., E-mail: luc.bonten@wur.nl [Alterra-Wageningen UR, Soil Science Centre, P.O. Box 47, 6700 AA Wageningen (Netherlands); Groenenberg, Jan E. [Alterra-Wageningen UR, Soil Science Centre, P.O. Box 47, 6700 AA Wageningen (Netherlands); Meesenburg, Henning [Northwest German Forest Research Station, Abt. Umweltkontrolle, Sachgebiet Intensives Umweltmonitoring, Goettingen (Germany); Vries, Wim de [Alterra-Wageningen UR, Soil Science Centre, P.O. Box 47, 6700 AA Wageningen (Netherlands)

    2011-10-15

    Various dynamic soil chemistry models have been developed to gain insight into impacts of atmospheric deposition of sulphur, nitrogen and other elements on soil and soil solution chemistry. Sorption parameters for anions and cations are generally calibrated for each site, which hampers extrapolation in space and time. On the other hand, recently developed surface complexation models (SCMs) have been successful in predicting ion sorption for static systems using generic parameter sets. This study reports the inclusion of an assemblage of these SCMs in the dynamic soil chemistry model SMARTml and applies this model to a spruce forest site in Solling Germany. Parameters for SCMs were taken from generic datasets and not calibrated. Nevertheless, modelling results for major elements matched observations well. Further, trace metals were included in the model, also using the existing framework of SCMs. The model predicted sorption for most trace elements well. - Highlights: > Surface complexation models can be well applied in field studies. > Soil chemistry under a forest site is adequately modelled using generic parameters. > The model is easily extended with extra elements within the existing framework. > Surface complexation models can show the linkages between major soil chemistry and trace element behaviour. - Surface complexation models with generic parameters make calibration of sorption superfluous in dynamic modelling of deposition impacts on soil chemistry under nature areas.

  20. Climate Warming Can Increase Soil Carbon Fluxes Without Decreasing Soil Carbon Stocks in Boreal Forests

    Science.gov (United States)

    Ziegler, S. E.; Benner, R. H.; Billings, S. A.; Edwards, K. A.; Philben, M. J.; Zhu, X.; Laganiere, J.

    2016-12-01

    Ecosystem C fluxes respond positively to climate warming, however, the net impact of changing C fluxes on soil organic carbon (SOC) stocks over decadal scales remains unclear. Manipulative studies and global-scale observations have informed much of the existing knowledge of SOC responses to climate, providing insights on relatively short (e.g. days to years) and long (centuries to millennia) time scales, respectively. Natural climate gradient studies capture integrated ecosystem responses to climate on decadal time scales. Here we report the soil C reservoirs, fluxes into and out of those reservoirs, and the chemical composition of inputs and soil organic matter pools along a mesic boreal forest climate transect. The sites studied consist of similar forest composition, successional stage, and soil moisture but differ by 5.2°C mean annual temperature. Carbon fluxes through these boreal forest soils were greatest in the lowest latitude regions and indicate that enhanced C inputs can offset soil C losses with warming in these forests. Respiration rates increased by 55% and the flux of dissolved organic carbon from the organic to mineral soil horizons tripled across this climate gradient. The 2-fold increase in litterfall inputs to these soils coincided with a significant increase in the organic horizon C stock with warming, however, no significant difference in the surface mineral soil C stocks was observed. The younger mean age of the mineral soil C ( 70 versus 330 YBP) provided further evidence for the greater turnover of SOC in the warmer climate soils. In spite of these differences in mean radiocarbon age, mineral SOC exhibited chemical characteristics of highly decomposed material across all regions. In contrast with depth trends in soil OM diagenetic indices, diagenetic shifts with latitude were limited to increases in C:N and alkyl to O-alkyl ratios in the overlying organic horizons in the warmer relative to the colder regions. These data indicate that the

  1. Beneath the veil: Plant growth form influences the strength of species richness-productivity relationships in forests

    Science.gov (United States)

    Oberle, B.; Grace, J.B.; Chase, J.M.

    2009-01-01

    Aim: Species richness has been observed to increase with productivity at large spatial scales, though the strength of this relationship varies among functional groups. In forests, canopy trees shade understorey plants, and for this reason we hypothesize that species richness of canopy trees will depend on macroclimate, while species richness of shorter growth forms will additionally be affected by shading from the canopy. In this study we test for differences in species richness-productivity relationships (SRPRs) among growth forms (canopy trees, shrubs, herbaceous species) in small forest plots. Location: We analysed 231 plots ranging from 34.0?? to 48.3?? N latitude and from 75.0?? to 124.2?? W longitude in the United States. Methods: We analysed data collected by the USDA Forest Inventory and Analysis program for plant species richness partitioned into different growth forms, in small plots. We used actual evapotranspiration as a macroclimatic estimate of regional productivity and calculated the area of light-blocking tissue in the immediate area surrounding plots for an estimate of the intensity of local shading. We estimated and compared SRPRs for different partitions of the species richness dataset using generalized linear models and we incorporated the possible indirect effects of shading using a structural equation model. Results: Canopy tree species richness increased strongly with regional productivity, while local shading primarily explained the variation in herbaceous plant richness. Shrub species richness was related to both regional productivity and local shading. Main conclusions: The relationship between total forest plant species richness and productivity at large scales belies strong effects of local interactions. Counter to the pattern for overall richness, we found that understorey herbaceous plant species richness does not respond to regional productivity gradients, and instead is strongly influenced by canopy density, while shrub species

  2. The partitioning of mercury in the solids components of forest soils and flooded forest soils in a hydroelectric reservoir, Quebec

    International Nuclear Information System (INIS)

    Dmytriw, R.P.

    1993-11-01

    Upon inundation, the soils in a hydroelection reservoir are subjected to several years of physical, biological and chemical changes as the transition from a terrestrial to an aquatic ecosystem is achieved. Changes in Eh, pH and microbial activity are believed to alter the metal binding capacity of solid substrates (organic matter, reactive Fe and Mn oxides, and clay minerals) within the soil profile, leading to remobilization of mercury associated with these phases. Four cores were collected along a transect from an unflooded forest soil to a pre-impoundment lake bottom sediment in the La-Grande-2 reservoir and watershed. The samples were sequentially extracted to determine the distribution of mercury between three operationally defined solid compartments: organic carbon, reactive Fe and Mn oxides/hydroxides, and the solid clay residue. Results indicate that up to 80% of the mercury in the O-horizon in forest soils and flooded forest soils, and up to 85% of the mercury in the lake sediments is bound to NaOH extractable organic carbon fractions. In the B-horizon podzol where organic content is low, 40-60% of the total mercury was found to be associated with reactive Fe minerals. In contrast, the flooded soil contains very little reactive Fe at any depth and the associated mercury concentrations are low. It is proposed that, upon inundation, oxide minerals are reduced and Hg released to the pore waters where it is immediately bound to an available substrate. Analyses of the residues suggests that there is an enrichment of mercury in the residual fraction immediately above the B-horizon of a flooded soil while the sulfide mineralization appears to play a role in sequestering mercury in lake sediments. 14 refs., 22 figs., 3 tabs

  3. Litter input controls on soil carbon in a temperate deciduous forest

    DEFF Research Database (Denmark)

    Bowden, Richard D.; Deem, Lauren; Plante, Alain F.

    2014-01-01

    Above- and belowground litter inputs in a temperate deciduous forest were altered for 20 yr to determine the importance of leaves and roots on soil C and soil organic matter (SOM) quantity and quality. Carbon and SOM quantity and quality were measured in the O horizon and mineral soil to 50 cm...... soil C, but decreases in litter inputs resulted in rapid soil C declines. Root litter may ultimately provide more stable sources of soil C. Management activities or environmental alterations that decrease litter inputs in mature forests can lower soil C content; however, increases in forest...

  4. Trophic conditions of forest soils of the Pieniny National Park, southern Poland

    Directory of Open Access Journals (Sweden)

    Wanic Tomasz

    2017-12-01

    Full Text Available The primary objective of this study was to characterise the edaphic conditions of forest areas in the Pieniny National Park (PNP, and to describe the dependencies between properties of forest soils and types of forest plant communities. The “Soil Trophic Index” (SIGg for mountainous areas was applied. The evaluation of the trophism for 74 forest monitoring employed the soil trophic index for mountainous areas SIGg or SIGgo. Plant communities in the forest monitoring areas were classified according to the Braun-Blanquet’s phytosociological method. Soils of PNP present in the forest monitoring areas were mostly classified as eutrophic brown soils (72.9%, rendzinas (10.8%, brown rendzinas (5.41%, and rubble initial soils (5.41%. Pararendzinas, dystrophic brown soils, and gley soils were less common (total below 5.5%. In the forest monitoring areas of PNP, eutrophic soils predominate over mesotrophic soils. High SIGg index of the soils is caused by high values of acidity and nitrogen content. The Carpathian beech forest Dentario glandulosae-Fagetum and thermophilic beech forest Carici albae-Fagetum associations are characterised by high naturalness and compatibility of theoretical habitats. The soils of the Carpathian fir forest Dentario glandulosae-Fagetum abietetosum subcommunity is characterised by a higher share of silt and clay particles and lower acidity as compared to the Carpathian beech forest Dentario glandulosae-Fagetum typicum subcommunity. The soils of the forest monitoring areas in PNP stand out in terms of their fertility against forest soils in other mountainous areas in Poland.

  5. Maximum temperature accounts for annual soil CO2 efflux in temperate forests of Northern China

    Science.gov (United States)

    Zhou, Zhiyong; Xu, Meili; Kang, Fengfeng; Jianxin Sun, Osbert

    2015-01-01

    It will help understand the representation legality of soil temperature to explore the correlations of soil respiration with variant properties of soil temperature. Soil temperature at 10 cm depth was hourly logged through twelve months. Basing on the measured soil temperature, soil respiration at different temporal scales were calculated using empirical functions for temperate forests. On monthly scale, soil respiration significantly correlated with maximum, minimum, mean and accumulated effective soil temperatures. Annual soil respiration varied from 409 g C m−2 in coniferous forest to 570 g C m−2 in mixed forest and to 692 g C m−2 in broadleaved forest, and was markedly explained by mean soil temperatures of the warmest day, July and summer, separately. These three soil temperatures reflected the maximum values on diurnal, monthly and annual scales. In accordance with their higher temperatures, summer soil respiration accounted for 51% of annual soil respiration across forest types, and broadleaved forest also had higher soil organic carbon content (SOC) and soil microbial biomass carbon content (SMBC), but a lower contribution of SMBC to SOC. This added proof to the findings that maximum soil temperature may accelerate the transformation of SOC to CO2-C via stimulating activities of soil microorganisms. PMID:26179467

  6. Hypholoma lateritium isolated from coarse woody debris, the forest floor, and mineral soil in a deciduous forest in New Hampshire

    Science.gov (United States)

    Therese A. Thompson; R. Greg Thorn; Kevin T. Smith

    2012-01-01

    Fungi in the Agaricomycetes (Basidiomycota) are the primary decomposers in temperate forests of dead wood on and in the forest soil. Through the use of isolation techniques selective for saprotrophic Agaricomycetes, a variety of wood decay fungi were isolated from a northern hardwood stand in the Bartlett Experimental Forest, New Hampshire, USA. In particular,

  7. Natural radionuclides in soils from Sao Paulo State cerrado forest

    International Nuclear Information System (INIS)

    Miranda, Marcia V.F.E.S.; Farias, Emerson E.G. de; Cantinha, Rebeca S.; Franca, Elvis J. de

    2015-01-01

    Considering the long life history, forests should be preferentially evaluated for the monitoring of radionuclides, mainly artificial radioisotopes. However, little is known about nuclides from Uranium and Thorium series, as well as, K-40, in soils from the Sao Paulo State forests. Soils are the main reservoir of natural radionuclides for vegetation, thereby deserving attention. Taking into account the advantages of High-Resolution Gamma-ray Spectrometry (HRGS), diverse radionuclides can be quantified simultaneously. In this work natural radionuclides in soils from the Estacao Ecologica de Assis were evaluated by HRGS. Samples of 0-10 cm depth were collected under crown projection of most abundant tree species of long-term plots installed within the Estacao Ecologica de Assis, Sao Paulo State, Brazil. After drying and milling until 0.5 mm particle size, test portions of 30 g were transferred to polypropylene vials, sealed with silicone and kept under controlled conditions until 30 days to achieve secular equilibrium. A group of gamma-ray spectrometers was used to analyze about 27 samples by 80,000 seconds. Activity concentrations of Pb-214, Ac-228 and K-40 and their respective expanded analytical uncertainties at the 95% confidence level were calculated by Genie software from Canberra. Abnormal values were not detected for radionuclides in soils samples, however K-40 activity concentrations changed considerably due to the mineral cycling, in which K and, consequently K-40, is mainly stocked in vegetation in spite of soils. (author)

  8. Natural radionuclides in soils from Sao Paulo State cerrado forest

    Energy Technology Data Exchange (ETDEWEB)

    Miranda, Marcia V.F.E.S.; Farias, Emerson E.G. de; Cantinha, Rebeca S.; Franca, Elvis J. de, E-mail: mvaleria@cnen.gov.br, E-mail: emersonemiliano@yahoo.com.br, E-mail: rebecanuclear@gmail.com, E-mail: ejfranca@cnen.gov.br [Centro Regional de Ciencias Nucleares do Nordeste (CRCN-NE/CNEN-PE), Recife, PE (Brazil)

    2015-07-01

    Considering the long life history, forests should be preferentially evaluated for the monitoring of radionuclides, mainly artificial radioisotopes. However, little is known about nuclides from Uranium and Thorium series, as well as, K-40, in soils from the Sao Paulo State forests. Soils are the main reservoir of natural radionuclides for vegetation, thereby deserving attention. Taking into account the advantages of High-Resolution Gamma-ray Spectrometry (HRGS), diverse radionuclides can be quantified simultaneously. In this work natural radionuclides in soils from the Estacao Ecologica de Assis were evaluated by HRGS. Samples of 0-10 cm depth were collected under crown projection of most abundant tree species of long-term plots installed within the Estacao Ecologica de Assis, Sao Paulo State, Brazil. After drying and milling until 0.5 mm particle size, test portions of 30 g were transferred to polypropylene vials, sealed with silicone and kept under controlled conditions until 30 days to achieve secular equilibrium. A group of gamma-ray spectrometers was used to analyze about 27 samples by 80,000 seconds. Activity concentrations of Pb-214, Ac-228 and K-40 and their respective expanded analytical uncertainties at the 95% confidence level were calculated by Genie software from Canberra. Abnormal values were not detected for radionuclides in soils samples, however K-40 activity concentrations changed considerably due to the mineral cycling, in which K and, consequently K-40, is mainly stocked in vegetation in spite of soils. (author)

  9. Radiocarbon dating of magnetic and non magnetic soil fractions as a method to estimate the heterotrophic component of soil respiration in a primary forest of Ghana.

    Science.gov (United States)

    Chiti, T.; Certini, G.; Marzaioli, F.; Valentini, R.

    2012-04-01

    We estimated the heterotrophic component (Rh) of soil respiration in a primary forest of Ghana by radiocarbon dating, a method we already successfully applied in temperate and Mediterranean forests. In this case, given the advanced stage of alteration of tropical soils, which are thus rich in oxides, we implemented the method on soil fractions obtained by High Gradient Magnetic Separation (HGMS), hence based on different degrees of magnetic susceptibility. In particular, we separated an organic pool associated with magnetic minerals (e.g iron oxides) from an organic pool engaged with non-magnetic minerals. This non destructive method of fractionation, often applied to the finest fraction of soil (clay), is here attempted on the bulk fine earth (sieved at 2 mm and further at 0.5 mm ,so as to have two size fractions: 2 to 0.5 mm and aggregates. Surprisingly, the non magnetic fraction is not influenced at all by the bomb C (negative delta 14) already at a depth of 5-15 cm and, even, at 15-30 cm all the four fractions have pre-bomb C, which means relatively high radiocarbon age. The finest fractions are the main contributors to the Rh flux, particularly the magnetic fraction (analysis of the bulk soil alone, and only by means of a SOC fractionation the Rh flux can be estimated quite accurately. This alternative approach for estimating the Rh component of CO2 from soils of tropical areas is currently being applied in 10 tropical forest sites in western and central Africa in the context of the ERC Africa GHG project, and together with measurements of the C inputs annually entering the soil will allow determining the sink-source capacity of primary forest soils.

  10. Concentrations and flux measurements of volatile organic compounds (VOC) in boreal forest soil

    Science.gov (United States)

    Mäki, Mari; Aaltonen, Hermanni; Heinonsalo, Jussi; Hellén, Heidi; Pumpanen, Jukka; Bäck, Jaana

    2017-04-01

    Volatile organic compounds (VOC) impact soil processes as VOCs transmit signals between roots and rhizosphere (Ditengou et al., 2015), VOCs can regulate microbial activity (Asensio et al., 2012), and VOCs can also promote root growth (Hung et al., 2012). Belowground concentrations of VOCs have not been measured in situ and for this reason, knowledge of how different soil organisms such as roots, rhizosphere and decomposers contribute to VOC production is limited. The aim of this study was to determine and quantify VOC fluxes and concentrations of different horizons from boreal forest soil. The VOC concentrations and fluxes were measured from Scots pine (Pinus sylvestris) forest soil at the SMEAR II station in southern Finland from 21th of April to 2nd of December in 2016. VOC fluxes were measured using dynamic (flow-through) chambers from five soil collars placed on five different locations. VOC concentrations were also measured in each location from four different soil horizons with the measurement depth 1-107 cm. VOCs were collected from underground gas collectors into the Tenax-Carbopack-B adsorbent tubes using portable pumps ( 100 ml min-1). The VOC concentrations and fluxes of isoprene, 11 monoterpenes, 13 sesquiterpenes and different oxygenated VOCs were measured. Sample tubes were analyzed using thermal desorption-gas chromatograph-mass spectrometry (TD-GC-MS). Soil temperature and soil water content were continuously monitored for each soil horizon. Our preliminary results show that the primary source of VOCs is organic soil layer and the contribution of mineral soil to the VOC formation is minor. VOC fluxes and concentrations were dominated by monoterpenes such as α-pinene, camphene, β-pinene, and Δ3-carene. Monoterpene concentration is almost 10-fold in organic soil compared to the deeper soil layers. However, the highest VOC fluxes on the soil surface were measured in October, whereas the monoterpene concentrations in organic soil were highest in July

  11. Nature and Properties of Some Forest Soils in the Mhite Mountains of New Hampshire

    Science.gov (United States)

    M.C. Hoyle; M.C. Hoyle

    1973-01-01

    Forested, podzol soils in the White Mountains of New Hampshire have developed in granitic, glacial material. They are coarse textured, acidic, and infertile. As a result of the latter condition, these soils can sustain a forest, but that forest is not healthy and vigorous.

  12. Retention of available P in acid soils of tropical and subtropical evergreen broad-leaved forests

    Institute of Scientific and Technical Information of China (English)

    CHEN Jianhui; ZOU Xiaoming; YANG Xiaodong

    2007-01-01

    Precipitation of mineral phosphate is often recognized as a factor of limiting the availability of P in acidic soils of tropical and subtropical forests.For this paper,we studied the extractable P pools and their transformation rates in soils of a tropical evergreen forest at Xishuangbanna and a subtropical montane wet forest at the Ailao Mountains in order to understand the biogeochemical processes regulating P availability in acidic soils.The two forests differ in forest humus layer;it is deep in the Ailao forest while little is present in the Xishuangbanna forest.The extractable P pools by resin and sodium-bicarbonate decreased when soil organic carbon content was reduced.The lowest levels of extractable P pools occurred in the surface (0-10 era) mineral soils of the Xishuangbanna forest.However,microbial P in the mineral soil of the Xishuangbauna forest was twice that in the Ailao forest.Potential rates of microbial P immobilization were greater than those of organic P mineralization in mineral soils for both forests.We suggest that microbial P immobilization plays an essential role in avoiding mineral P precipitation and retaining available P of plant in tropical acidic soils,whereas both floor mass accumulation and microbial P immobilization function benefit retaining plant available P in subtropical montane wet forests.

  13. Nitrogen fertilization decreases forest soil fungal and bacterial biomass in three long-term experiments

    Science.gov (United States)

    Matthew D. Wallenstein; Steven McNulty; Ivan J. Fernandez; Johnny Boggs; William H. Schlesinger

    2006-01-01

    We examined the effects of N fertilization on forest soil fungal and bacterial biomass at three long-term experiments in New England (Harvard Forest, MA; Mt. Ascutney, VT; Bear Brook, ME). At Harvard Forest, chronic N fertilization has decreased organic soil microbial biomass C (MBC) by an average of 54% and substrate induced respiration (SIR) was decreased by an...

  14. Moss and soil contributions to the annual net carbon flux of a maturing boreal forest

    Science.gov (United States)

    Harden, J.W.; O'Neill, K. P.; Trumbore, S.E.; Veldhuis, H.; Stocks, B.J.

    1997-01-01

    We used input and decomposition data from 14C studies of soils to determine rates of vertical accumulation of moss combined with carbon storage inventories on a sequence of burns to model how carbon accumulates in soils and moss after a stand-killing fire. We used soil drainage - moss associations and soil drainage maps of the old black spruce (OBS) site at the BOREAS northern study area (NSA) to areally weight the contributions of each moderately well drained, feathermoss areas; poorly drained sphagnum - feathermoss areas; and very poorly drained brown moss areas to the carbon storage and flux at the OBS NSA site. On this very old (117 years) complex of black spruce, sphagnum bog veneer, and fen systems we conclude that these systems are likely sequestering 0.01-0.03 kg C m-2 yr-' at OBS-NSA today. Soil drainage in boreal forests near Thompson, Manitoba, controls carbon storage and flux by controlling moss input and decomposition rates and by controlling through fire the amount and quality of carbon left after burning. On poorly drained soils rich in sphagnum moss, net accumulation and long-term storage of carbon is higher than on better drained soils colonized by feathermosses. The carbon flux of these contrasting ecosystems is best characterized by soil drainage class and stand age, where stands recently burned are net sources of CO2, and maturing stands become increasingly stronger sinks of atmospheric CO2. This approach to measuring carbon storage and flux presents a method of scaling to larger areas using soil drainage, moss cover, and stand age information.

  15. Iron Redox Dynamics in Humid Tropical Forest Soils: Carbon Stabilization vs. Degradation?

    Science.gov (United States)

    Hall, S. J.; Silver, W. L.; Hammel, K.

    2015-12-01

    Most terrestrial soils exhibit a patchwork of oxygen (O2) availability that varies over spatial scales of microsites to catenas to landscapes, and over temporal scales of minutes to seasons. Oxygen fluctuations often drive microbial iron (Fe) reduction and abiotic/biotic Fe oxidation at the microsite scale, contributing to anaerobic carbon (C) mineralization and changes in soil physical and chemical characteristics, especially the dissolution and precipitation of short-range ordered Fe phases thought to stabilize C. Thus, O2 fluctuations and Fe redox cycling may have multiple nuanced and opposing impacts on different soil C pools, illustrated by recent findings from Fe-rich Oxisols and Ultisols in the Luquillo Experimental Forest, Puerto Rico. Spatial patterns in surface soil C stocks at the landscape scale correlated strongly (R2 = 0.98) with concentrations of reduced Fe (Fe(II)), reflecting constitutive differences in reducing conditions within and among sites that promote C accumulation in mineral soil horizons. Similarly, turnover times of a decadal-cycling pool of mineral-associated organic matter increased with Fe(II) across a catena, possibly reflecting the role of anaerobic microsites in long-term C stabilization. However, two different indices of short-range order Fe showed highly significant opposing relationships (positive and negative) with spatial variation in soil C concentrations, possibly reflecting a dual role of Fe in driving C stabilization via co-precipitation, and C solubilization and loss following dissimilatory Fe reduction. Consistent with the field data, laboratory incubations demonstrated that redox fluctuations can increase the contribution of biochemically recalcitrant C (lignin) to soil respiration, whereas addition of short-range order Fe dramatically suppressed lignin mineralization but had no impact on bulk soil respiration. Thus, understanding spatial and temporal patterns of Fe redox cycling may provide insight into explaining the

  16. Plant species richness sustains higher trophic levels of soil nematode communities after consecutive environmental perturbations.

    Science.gov (United States)

    Cesarz, Simone; Ciobanu, Marcel; Wright, Alexandra J; Ebeling, Anne; Vogel, Anja; Weisser, Wolfgang W; Eisenhauer, Nico

    2017-07-01

    The magnitude and frequency of extreme weather events are predicted to increase in the future due to ongoing climate change. In particular, floods and droughts resulting from climate change are thought to alter the ecosystem functions and stability. However, knowledge of the effects of these weather events on soil fauna is scarce, although they are key towards functioning of terrestrial ecosystems. Plant species richness has been shown to affect the stability of ecosystem functions and food webs. Here, we used the occurrence of a natural flood in a biodiversity grassland experiment that was followed by a simulated summer drought experiment, to investigate the interactive effects of plant species richness, a natural flood, and a subsequent summer drought on nematode communities. Three and five months after the natural flooding, effects of flooding severity were still detectable in the belowground system. We found that flooding severity decreased soil nematode food-web structure (loss of K-strategists) and the abundance of plant feeding nematodes. However, high plant species richness maintained higher diversity and abundance of higher trophic levels compared to monocultures throughout the flood. The subsequent summer drought seemed to be of lower importance but reversed negative flooding effects in some cases. This probably occurred because the studied grassland system is well adapted to drought, or because drought conditions alleviated the negative impact of long-term soil waterlogging. Using soil nematodes as indicator taxa, this study suggests that high plant species richness can maintain soil food web complexity after consecutive environmental perturbations.

  17. [Soil hydrolase characteristics in late soil-thawing period in subalpine/alpine forests of west Sichuan].

    Science.gov (United States)

    Tan, Bo; Wu, Fu-Zhong; Yang, Wan-Qin; Yu, Sheng; Yang, Yu-Lian; Wang, Ao

    2011-05-01

    Late soil-thawing period is a critical stage connecting winter and growth season. The significant temperature fluctuation at this stage might have strong effects on soil ecological processes. In order to understand the soil biochemical processes at this stage in the subalpine/alpine forests of west Sichuan, soil samples were collected from the representative forests including primary fir forest, fir and birch mixed forest, and secondary fir forest in March 5-April 25, 2009, with the activities of soil invertase, urease, and phosphatase (neutral, acid and alkaline phosphatases) measured. In soil frozen period, the activities of the three enzymes in test forests still kept relatively higher. With the increase of soil temperature, the activities of hydrolases at the early stage of soil-thawing decreased rapidly after a sharp increase, except for neutral phosphatease. Thereafter, there was an increase in the activities of urease and phosphatase. Relative to soil mineral layer, soil organic layer had higher hydrolase activity in late soil-thawing period, and showed more obvious responses to the variation of soil temperature.

  18. Transformation of arsenic-rich copper smelter flue dust in contrasting soils: A 2-year field experiment.

    Science.gov (United States)

    Jarošíková, Alice; Ettler, Vojtěch; Mihaljevič, Martin; Penížek, Vít; Matoušek, Tomáš; Culka, Adam; Drahota, Petr

    2018-06-01

    Dust emissions from copper smelters processing arsenic-bearing ores represent a risk to soil environments due to the high levels of As and other inorganic contaminants. Using an in situ experiment in four different forest and grassland soils (pH 3.2-8.0) we studied the transformation of As-rich (>50 wt% As) copper smelter dust over 24 months. Double polyamide bags with 1 g of flue dust were buried at different depths in soil pits and in 6-month intervals; then those bags, surrounding soil columns, and soil pore waters were collected and analysed. Dust dissolution was relatively fast during the first 6 months (5-34%), and mass losses attained 52% after 24 months. The key driving forces affecting dust dissolution were not only pH, but also the water percolation/retention in individual soils. Primary arsenolite (As 2 O 3 ) dissolution was responsible for high As release from the dust (to 72%) and substantial increase of As in the soil (to a 56 × increase; to 1500 mg kg -1 ). Despite high arsenolite solubility, this phase persisted in the dust after 2 years of exposure. Mineralogical investigation indicated that mimetite [Pb 5 (AsO 4 ) 3 (Cl,OH)], unidentified complex Ca-Pb-Fe-Zn arsenates, and Fe oxyhydroxides partly controlled the mobility of As and other metal(loid)s. Compared to As, other less abundant contaminants (Bi, Cu, Pb, Sb, Zn) were released into the soil to a lesser extent (8-40% of total). The relatively high mobility of As in the soil can be seen from decreases of bulk As concentrations after spring snowmelt, high water-extractable fractions with up to ∼50% of As(III) in extracts, and high As concentrations in soil pore waters. Results indicate that efficient controls of emissions from copper smelters and flue dust disposal sites are needed to prevent extensive contamination of nearby soils by persistent As. Copyright © 2018 Elsevier Ltd. All rights reserved.

  19. Non-Linear Nitrogen Cycling and Ecosystem Calcium Depletion Along a Temperate Forest Soil Nitrogen Gradient

    Science.gov (United States)

    Sinkhorn, E. R.; Perakis, S. S.; Compton, J. E.; Cromack, K.; Bullen, T. D.

    2007-12-01

    Understanding how N availability influences base cation stores is critical for assessing long-term ecosystem sustainability. Indices of nitrogen (N) availability and the distribution of nutrients in plant biomass, soil, and soil water were examined across ten Douglas-fir (Pseudotsuga menziesii) stands spanning a three-fold soil N gradient (0-10 cm: 0.21 - 0.69% N, 0-100 cm: 9.2 - 28.8 Mg N ha-1) in the Oregon Coast Range. This gradient is largely the consequence of historical inputs from N2-fixing red alder stands that can add 100-200 kg N ha-1 yr-1 to the ecosystem for decades. Annual net N mineralization and litterfall N return displayed non-linear relationships with soil N, increasing initially, and then decreasing as N-richness increased. In contrast, nitrate leaching from deep soils increased linearly across the soil N gradient and ranged from 0.074 to 30 kg N ha-1 yr-1. Soil exchangeable Ca, Mg, and K pools to 1 m depth were negatively related to nitrate losses across sites. Ca was the only base cation exhibiting concentration decreases in both plant and soil pools across the soil N gradient, and a greater proportion of total available ecosystem Ca was sequestered in aboveground plant biomass at high N, low Ca sites. Our work supports a hierarchical model of coupled N-Ca cycles across gradients of soil N enrichment, with microbial production of mobile nitrate anions leading to depletion of readily available Ca at the ecosystem scale, and plant sequestration promoting Ca conservation as Ca supply diminishes. The preferential storage of Ca in aboveground biomass at high N and low Ca sites, while critical for sustaining plant productivity, may also predispose forests to Ca depletion in areas managed for intensive biomass removal. Long-term N enrichment of temperate forest soils appears capable of sustaining an open N cycle and key symptoms of N-saturation for multiple decades after the cessation of elevated N inputs.

  20. Radiocesium distribution in aggregate-size fractions of cropland and forest soils affected by the Fukushima nuclear accident.

    Science.gov (United States)

    Koarashi, Jun; Nishimura, Syusaku; Atarashi-Andoh, Mariko; Matsunaga, Takeshi; Sato, Tsutomu; Nagao, Seiya

    2018-08-01

    The Fukushima Daiichi nuclear power plant accident caused serious radiocesium ( 137 Cs) contamination in soils in a range of terrestrial ecosystems. It is well documented that the interaction of 137 Cs with soil constituents, particularly clay minerals, in surface soil layers exerts strong control on the behavior of this radionuclide in the environment; however, there is little understanding of how soil aggregation-the binding of soil particles together into aggregates-can affect the mobility and bioavailability of 137 Cs in soils. To explore this, soil samples were collected at seven sites under different land-use conditions in Fukushima and were separated into four aggregate-size fractions: clay-sized (fractions were then analyzed for 137 Cs content and extractability and mineral composition. In forest soils, aggregate formation was significant, and 69%-83% of 137 Cs was associated with macroaggregates and sand-sized aggregates. In contrast, there was less aggregation in agricultural field soils, and approximately 80% of 137 Cs was in the clay- and silt-sized fractions. Across all sites, the 137 Cs extractability was higher in the sand-sized aggregate fractions than in the clay-sized fractions. Mineralogical analysis showed that, in most soils, clay minerals (vermiculite and kaolinite) were present even in the larger-sized aggregate fractions. These results demonstrate that larger-sized aggregates are a significant reservoir of potentially mobile and bioavailable 137 Cs in organic-rich (forest and orchard) soils. Our study suggests that soil aggregation reduces the mobility of particle-associated 137 Cs through erosion and resuspension and also enhances the bioavailability of 137 Cs in soils. Copyright © 2018 Elsevier Ltd. All rights reserved.

  1. Soil quality standards and guidelines for forest sustainability in northwestern North America

    Science.gov (United States)

    Deborah Page-Dumroese; Martin Jurgensen; William Elliot; Thomas Rice; John Nesser; Thomas Collins; Robert. Meurisse

    2000-01-01

    Soil quality standards and guidelines of the USDA Forest Service were some of the first in the world to be developed to evaluate changes in forest soil productivity and sustainability after harvesting and site preparation. International and national development of criteria and indicators for maintenance of soil productivity make it imperative to have adequate threshold...

  2. Soil respiration response to prescribed burning and thinning in mixed-conifer and hardwood forests

    Science.gov (United States)

    Amy Concilio; Siyan Ma; Qinglin Li; James LeMoine; Jiquan Chen; Malcolm North; Daryl Moorhead; Randy Jensen

    2005-01-01

    The effects of management on soil carbon efflux in different ecosystems are still largely unknown yet crucial to both our understanding and management of global carbon flux. To compare the effects of common forest management practices on soil carbon cycling, we measured soil respiration rate (SRR) in a mixed-conifer and hardwood forest that had undergone various...

  3. Seasonal variation in soil and plant water potentials in a Bolivian tropical moist and dry forest

    NARCIS (Netherlands)

    Markesteijn, L.; Iraipi, J.; Bongers, F.; Poorter, L.

    2010-01-01

    We determined seasonal variation in soil matric potentials (¿soil) along a topographical gradient and with soil depth in a Bolivian tropical dry (1160 mm y-1 rain) and moist forest (1580 mm y-1). In each forest we analysed the effect of drought on predawn leaf water potentials (¿pd) and drought

  4. Evidence that soil aluminum enforces site fidelity of southern New England forest trees

    Science.gov (United States)

    S. W. Bigelow; C. D. Canham

    2010-01-01

    Tree species composition of hardwood forests of the northeastern United States corresponds with soil chemistry, and differential performance along soil calcium (Ca) gradients has been proposed as a mechanism for enforcing this fidelity of species to site. We conducted studies in a southern New England forest to test if surface-soil Ca is more important than other...

  5. Nitrogen dynamics in oak forest soils along a historical deposition gradient

    Science.gov (United States)

    Ralph E. J. Boerner; Elaine Kennedy Sutherland

    1995-01-01

    This study quantified soil nutrient status and N mineralization/nitrification potentials in soils of oakdominated, unmanaged forest stands in seven experimental forests ranging along a historical and current acidic deposition gradient from southern Illinois to central West Virginia, U.S.A. Among these seven sites (that spanned 8.5º of longitude) soil pH and Ca...

  6. Differential controls on soil carbon density and mineralization among contrasting forest types in a temperate forest ecosystem

    Science.gov (United States)

    You, Ye-Ming; Wang, Juan; Sun, Xiao-Lu; Tang, Zuo-Xin; Zhou, Zhi-Yong; Sun, Osbert Jianxin

    2016-01-01

    Understanding the controls on soil carbon dynamics is crucial for modeling responses of ecosystem carbon balance to global change, yet few studies provide explicit knowledge on the direct and indirect effects of forest stands on soil carbon via microbial processes. We investigated tree species, soil, and site factors in relation to soil carbon density and mineralization in a temperate forest of central China. We found that soil microbial biomass and community structure, extracellular enzyme activities, and most of the site factors studied varied significantly across contrasting forest types, and that the associations between activities of soil extracellular enzymes and microbial community structure appeared to be weak and inconsistent across forest types, implicating complex mechanisms in the microbial regulation of soil carbon metabolism in relation to tree species. Overall, variations in soil carbon density and mineralization are predominantly accounted for by shared effects of tree species, soil, microclimate, and microbial traits rather than the individual effects of the four categories of factors. Our findings point to differential controls on soil carbon density and mineralization among contrasting forest types and highlight the challenge to incorporate microbial processes for constraining soil carbon dynamics in global carbon cycle models. PMID:26925871

  7. A Canadian upland forest soil profile and carbon stocks database.

    Science.gov (United States)

    Shaw, Cindy; Hilger, Arlene; Filiatrault, Michelle; Kurz, Werner

    2018-04-01

    "A Canadian upland forest soil profile and carbon stocks database" was compiled in phases over a period of 10 years to address various questions related to modeling upland forest soil carbon in a national forest carbon accounting model. For 3,253 pedons, the SITES table contains estimates for soil organic carbon stocks (Mg/ha) in organic horizons and mineral horizons to a 100-cm depth, soil taxonomy, leading tree species, mean annual temperature, annual precipitation, province or territory, terrestrial ecozone, and latitude and longitude, with an assessment of the quality of information about location. The PROFILES table contains profile data (16,167 records by horizon) used to estimate the carbon stocks that appear in the SITES table, plus additional soil chemical and physical data, where provided by the data source. The exceptions to this are estimates for soil carbon stocks based on Canadian National Forest Inventory data (NFI [2006] in REFERENCES table), where data were collected by depth increment rather than horizon and, therefore, total soil carbon stocks were calculated separately before being entered into the SITES table. Data in the PROFILES table include the carbon stock estimate for each horizon (corrected for coarse fragment content), and the data used to calculate the carbon stock estimate, such as horizon thickness, bulk density, and percent organic carbon. The PROFILES table also contains data, when reported by the source, for percent carbonate carbon, pH, percent total nitrogen, particle size distribution (percent sand, silt, clay), texture class, exchangeable cations, cation and total exchange capacity, and percent Fe and Al. An additional table provides references (REFERENCES table) for the source data. Earlier versions of the database were used to develop national soil carbon modeling categories based on differences in carbon stocks linked to soil taxonomy and to examine the potential of using soil taxonomy and leading tree species to improve

  8. Validating visual disturbance types and classes used for forest soil monitoring protocols

    Science.gov (United States)

    D. S. Page-Dumroese; A. M. Abbott; M. P. Curran; M. F. Jurgensen

    2012-01-01

    We describe several methods for validating visual soil disturbance classes used during forest soil monitoring after specific management operations. Site-specific vegetative, soil, and hydrologic responses to soil disturbance are needed to identify sensitive and resilient soil properties and processes; therefore, validation of ecosystem responses can provide information...

  9. Species richness in soil bacterial communities: a proposed approach to overcome sample size bias.

    Science.gov (United States)

    Youssef, Noha H; Elshahed, Mostafa S

    2008-09-01

    Estimates of species richness based on 16S rRNA gene clone libraries are increasingly utilized to gauge the level of bacterial diversity within various ecosystems. However, previous studies have indicated that regardless of the utilized approach, species richness estimates obtained are dependent on the size of the analyzed clone libraries. We here propose an approach to overcome sample size bias in species richness estimates in complex microbial communities. Parametric (Maximum likelihood-based and rarefaction curve-based) and non-parametric approaches were used to estimate species richness in a library of 13,001 near full-length 16S rRNA clones derived from soil, as well as in multiple subsets of the original library. Species richness estimates obtained increased with the increase in library size. To obtain a sample size-unbiased estimate of species richness, we calculated the theoretical clone library sizes required to encounter the estimated species richness at various clone library sizes, used curve fitting to determine the theoretical clone library size required to encounter the "true" species richness, and subsequently determined the corresponding sample size-unbiased species richness value. Using this approach, sample size-unbiased estimates of 17,230, 15,571, and 33,912 were obtained for the ML-based, rarefaction curve-based, and ACE-1 estimators, respectively, compared to bias-uncorrected values of 15,009, 11,913, and 20,909.

  10. Evolution of soil, ecosystem, and critical zone research at the USDA FS Calhoun Experimental Forest

    Science.gov (United States)

    Daniel deB. Richter; Allan R. Bacon; Sharon A. Billings; Dan Binkley; Marilyn Buford; Mac Callaham; Amy E. Curry; Ryan L. Fimmen; A. Stuart Grandy; Paul R. Heine; Michael Hofmockel; Jason A. Jackson; Elisabeth LeMaster; Jianwei Li; Daniel Markewitz; Megan L. Mobley; Mary W. Morrison; Michael S. Strickland; Thomas Waldrop; Carol G. Wells

    2015-01-01

    The US Department of Agriculture (USDA) Forest Service Calhoun Experimental Forest was organized in 1947 on the southern Piedmont to engage in research that today is called restoration ecology, to improve soils, forests, and watersheds in a region that had been severely degraded by nearly 150 years farming. Today, this 2,050-ha research forest is managed by the Sumter...

  11. Gaseous mercury fluxes from forest soils in response to forest harvesting intensity: A field manipulation experiment

    International Nuclear Information System (INIS)

    Mazur, M.; Mitchell, C.P.J.; Eckley, C.S.; Eggert, S.L.; Kolka, R.K.; Sebestyen, S.D.; Swain, E.B.

    2014-01-01

    Forest harvesting leads to changes in soil moisture, temperature and incident solar radiation, all strong environmental drivers of soil–air mercury (Hg) fluxes. Whether different forest harvesting practices significantly alter Hg fluxes from forest soils is unknown. We conducted a field-scale experiment in a northern Minnesota deciduous forest wherein gaseous Hg emissions from the forest floor were monitored after two forest harvesting prescriptions, a traditional clear-cut and a clearcut followed by biomass harvest, and compared to an un-harvested reference plot. Gaseous Hg emissions were measured in quadruplicate at four different times between March and November 2012 using Teflon dynamic flux chambers. We also applied enriched Hg isotope tracers and separately monitored their emission in triplicate at the same times as ambient measurements. Clearcut followed by biomass harvesting increased ambient Hg emissions the most. While significant intra-site spatial variability was observed, Hg emissions from the biomass harvested plot (180 ± 170 ng m −2 d −1 ) were significantly greater than both the traditional clearcut plot (− 40 ± 60 ng m −2 d −1 ) and the un-harvested reference plot (− 180 ± 115 ng m −2 d −1 ) during July. This difference was likely a result of enhanced Hg 2+ photoreduction due to canopy removal and less shading from downed woody debris in the biomass harvested plot. Gaseous Hg emissions from more recently deposited Hg, as presumably representative of isotope tracer measurements, were not significantly influenced by harvesting. Most of the Hg tracer applied to the forest floor became sequestered within the ground vegetation and debris, leaf litter, and soil. We observed a dramatic lessening of tracer Hg emissions to near detection levels within 6 months. As post-clearcutting residues are increasingly used as a fuel or fiber resource, our observations suggest that gaseous Hg emissions from forest soils will increase, although it

  12. [Effects of climate change on forest soil organic carbon storage: a review].

    Science.gov (United States)

    Zhou, Xiao-yu; Zhang, Cheng-yi; Guo, Guang-fen

    2010-07-01

    Forest soil organic carbon is an important component of global carbon cycle, and the changes of its accumulation and decomposition directly affect terrestrial ecosystem carbon storage and global carbon balance. Climate change would affect the photosynthesis of forest vegetation and the decomposition and transformation of forest soil organic carbon, and further, affect the storage and dynamics of organic carbon in forest soils. Temperature, precipitation, atmospheric CO2 concentration, and other climatic factors all have important influences on the forest soil organic carbon storage. Understanding the effects of climate change on this storage is helpful to the scientific management of forest carbon sink, and to the feasible options for climate change mitigation. This paper summarized the research progress about the distribution of organic carbon storage in forest soils, and the effects of elevated temperature, precipitation change, and elevated atmospheric CO2 concentration on this storage, with the further research subjects discussed.

  13. Chemical composition of the humus layer, mineral soil and soil solution of 200 forest stands in the Netherlands in 1995

    NARCIS (Netherlands)

    Leeters, E.E.J.M.; Vries, de W.

    2001-01-01

    A nationwide assessment of the chemical composition of the soil solid phase and the soil solution in the humus layer and two mineral layers (0-10 cm and 10-30 cm) was made for 200 forest stands in the year 1995. The stands were part of the national forest inventory on vitality, included seven tree

  14. The influence of site factors on nitrogen mineralization in forest soils ...

    African Journals Online (AJOL)

    The influence of site factors on nitrogen mineralization in forest soils of the ... on N mineralization, as well as the effect of N mineralization on forest productivity. ... of the natural log of mean annual temperature, geological substrate and total N ...

  15. Carbon input increases microbial nitrogen demand, but not microbial nitrogen mining in boreal forest soils

    Science.gov (United States)

    Wild, Birgit; Alaei, Saeed; Bengtson, Per; Bodé, Samuel; Boeckx, Pascal; Schnecker, Jörg; Mayerhofer, Werner; Rütting, Tobias

    2016-04-01

    Plant primary production at mid and high latitudes is often limited by low soil N availability. It has been hypothesized that plants can indirectly increase soil N availability via root exudation, i.e., via the release of easily degradable organic compounds such as sugars into the soil. These compounds can stimulate microbial activity and extracellular enzyme synthesis, and thus promote soil organic matter (SOM) decomposition ("priming effect"). Even more, increased C availability in the rhizosphere might specifically stimulate the synthesis of enzymes targeting N-rich polymers such as proteins that store most of the soil N, but are too large for immediate uptake ("N mining"). This effect might be particularly important in boreal forests, where plants often maintain high primary production in spite of low soil N availability. We here tested the hypothesis that increased C availability promotes protein depolymerization, and thus soil N availability. In a laboratory incubation experiment, we added 13C-labeled glucose to a range of soil samples derived from boreal forests across Sweden, and monitored the release of CO2 by C mineralization, distinguishing between CO2 from the added glucose and from the native, unlabeled soil organic C (SOC). Using a set of 15N pool dilution assays, we further measured gross rates of protein depolymerization (the breakdown of proteins into amino acids) and N mineralization (the microbial release of excess N as ammonium). Comparing unamended control samples, we found a high variability in C and N mineralization rates, even when normalized by SOC content. Both C and N mineralization were significantly correlated to SOM C/N ratios, with high C mineralization at high C/N and high N mineralization at low C/N, suggesting that microorganisms adjusted C and N mineralization rates to the C/N ratio of their substrate and released C or N that was in excess. The addition of glucose significantly stimulated the mineralization of native SOC in soils

  16. Can Airborne Laser Scanning (ALS and Forest Estimates Derived from Satellite Images Be Used to Predict Abundance and Species Richness of Birds and Beetles in Boreal Forest?

    Directory of Open Access Journals (Sweden)

    Eva Lindberg

    2015-04-01

    Full Text Available In managed landscapes, conservation planning requires effective methods to identify high-biodiversity areas. The objective of this study was to evaluate the potential of airborne laser scanning (ALS and forest estimates derived from satellite images extracted at two spatial scales for predicting the stand-scale abundance and species richness of birds and beetles in a managed boreal forest landscape. Multiple regression models based on forest data from a 50-m radius (i.e., corresponding to a homogenous forest stand had better explanatory power than those based on a 200-m radius (i.e., including also parts of adjacent stands. Bird abundance and species richness were best explained by the ALS variables “maximum vegetation height” and “vegetation cover between 0.5 and 3 m” (both positive. Flying beetle abundance and species richness, as well as epigaeic (i.e., ground-living beetle richness were best explained by a model including the ALS variable “maximum vegetation height” (positive and the satellite-derived variable “proportion of pine” (negative. Epigaeic beetle abundance was best explained by “maximum vegetation height” at 50 m (positive and “stem volume” at 200 m (positive. Our results show that forest estimates derived from satellite images and ALS data provide complementary information for explaining forest biodiversity patterns. We conclude that these types of remote sensing data may provide an efficient tool for conservation planning in managed boreal landscapes.

  17. Unravelling the importance of forest age stand and forest structure driving microbiological soil properties, enzymatic activities and soil nutrients content in Mediterranean Spanish black pine(Pinus nigra Ar. ssp. salzmannii) Forest.

    Science.gov (United States)

    Lucas-Borja, M E; Hedo, J; Cerdá, A; Candel-Pérez, D; Viñegla, B

    2016-08-15

    This study aimed to investigate the effects that stand age and forest structure have on microbiological soil properties, enzymatic activities and nutrient content. Thirty forest compartments were randomly selected at the Palancares y Agregados managed forest area (Spain), supporting forest stands of five ages; from 100 to 80years old to compartments with trees that were 19-1years old. Forest area ranging from 80 to 120years old and without forest intervention was selected as the control. We measured different soil enzymatic activities, soil respiration and nutrient content (P, K, Na, Mg, Cr, Mn, Fe, Co, Ni, Cu, Zn, Pb and Ca) in the top cm of 10 mineral soils in each compartment. Results showed that the lowest forest stand age and the forest structure created by management presented lower values of organic matter, soil moisture, water holding capacity and litterfall and higher values of C/N ratio in comparison with the highest forest stand age and the related forest structure, which generated differences in soil respiration and soil enzyme activities. The forest structure created by no forest management (control plot) presented the highest enzymatic activities, soil respiration, NH4(+) and NO3(-). Results did not show a clear trend in nutrient content comparing all the experimental areas. Finally, the multivariate PCA analysis clearly clustered three differentiated groups: Control plot; from 100 to 40years old and from 39 to 1year old. Our results suggest that the control plot has better soil quality and that extreme forest stand ages (100-80 and 19-1years old) and the associated forest structure generates differences in soil parameters but not in soil nutrient content. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Soil does not explain monodominance in a Central African tropical forest.

    Directory of Open Access Journals (Sweden)

    Kelvin S-H Peh

    2011-02-01

    Full Text Available Soil characteristics have been hypothesised as one of the possible mechanisms leading to monodominance of Gilbertiodendron dewerei in some areas of Central Africa where higher-diversity forest would be expected. However, the differences in soil characteristics between the G. dewevrei-dominated forest and its adjacent mixed forest are still poorly understood. Here we present the soil characteristics of the G. dewevrei forest and quantify whether soil physical and chemical properties in this monodominant forest are significantly different from the adjacent mixed forest.We sampled top soil (0-5, 5-10, 10-20, 20-30 cm and subsoil (150-200 cm using an augur in 6 × 1 ha areas of intact central Africa forest in SE Cameroon, three independent patches of G. dewevrei-dominated forest and three adjacent areas (450-800 m apart, all chosen to be topographically homogeneous. Analysis--subjected to Bonferroni correction procedure--revealed no significant differences between the monodominant and mixed forests in terms of soil texture, median particle size, bulk density, pH, carbon (C content, nitrogen (N content, C:N ratio, C:total NaOH-extractable P ratio and concentrations of labile phosphorous (P, inorganic NaOH-extractable P, total NaOH-extractable P, aluminium, barium, calcium, copper, iron, magnesium, manganese, molybdenum, nickel, potassium, selenium, silicon, sodium and zinc. Prior to Bonferroni correction procedure, there was a significant lower level of silicon concentration found in the monodominant than mixed forest deep soil; and a significant lower level of nickel concentration in the monodominant than mixed forest top soil. Nevertheless, these were likely to be the results of multiple tests of significance.Our results do not provide clear evidence of soil mediation for the location of monodominant forests in relation to adjacent mixed forests. It is also likely that G. dewevrei does not influence soil chemistry in the monodominant forests.

  19. Soil does not explain monodominance in a Central African tropical forest.

    Science.gov (United States)

    Peh, Kelvin S-H; Sonké, Bonaventure; Lloyd, Jon; Quesada, Carlos A; Lewis, Simon L

    2011-02-10

    Soil characteristics have been hypothesised as one of the possible mechanisms leading to monodominance of Gilbertiodendron dewerei in some areas of Central Africa where higher-diversity forest would be expected. However, the differences in soil characteristics between the G. dewevrei-dominated forest and its adjacent mixed forest are still poorly understood. Here we present the soil characteristics of the G. dewevrei forest and quantify whether soil physical and chemical properties in this monodominant forest are significantly different from the adjacent mixed forest. We sampled top soil (0-5, 5-10, 10-20, 20-30 cm) and subsoil (150-200 cm) using an augur in 6 × 1 ha areas of intact central Africa forest in SE Cameroon, three independent patches of G. dewevrei-dominated forest and three adjacent areas (450-800 m apart), all chosen to be topographically homogeneous. Analysis--subjected to Bonferroni correction procedure--revealed no significant differences between the monodominant and mixed forests in terms of soil texture, median particle size, bulk density, pH, carbon (C) content, nitrogen (N) content, C:N ratio, C:total NaOH-extractable P ratio and concentrations of labile phosphorous (P), inorganic NaOH-extractable P, total NaOH-extractable P, aluminium, barium, calcium, copper, iron, magnesium, manganese, molybdenum, nickel, potassium, selenium, silicon, sodium and zinc. Prior to Bonferroni correction procedure, there was a significant lower level of silicon concentration found in the monodominant than mixed forest deep soil; and a significant lower level of nickel concentration in the monodominant than mixed forest top soil. Nevertheless, these were likely to be the results of multiple tests of significance. Our results do not provide clear evidence of soil mediation for the location of monodominant forests in relation to adjacent mixed forests. It is also likely that G. dewevrei does not influence soil chemistry in the monodominant forests.

  20. [Soil meso- and micro-fauna community structures in different urban forest types in Shanghai, China.

    Science.gov (United States)

    Jin, Shi Ke; Wang, Juan Juan; Zhu, Sha; Zhang, Qi; Li, Xiang; Zheng, Wen Jing; You, Wen Hui

    2016-07-01

    Soil meso- and micro-fauna of four urban forest types in Shanghai were investigated in four months which include April 2014, July 2014, October 2014 and January 2015. A total of 2190 soil fauna individuals which belong to 6 phyla, 15 classes and 22 groups were collected. The dominant groups were Nematoda and Arcari, accounting for 56.0% and 21.8% of the total in terms of individual numbers respectively. The common groups were Enchytraeidae, Rotatoria, Collembola and Hymenoptera and they accounted for 18.7% of the total in terms of individual numbers. There was a significant difference (PMetasequoia glyptostroboides forest, the smallest in Cinnamomum camphora forest. The largest groupe number was found in near-nature forest, the smallest was found in M. glyptostroboides forest. There was obvious seasonal dynamics in each urban forest type and green space which had larger density in autumn and larger groupe number in summer and autumn. In soil profiles, the degree of surface accumulation of soil meso- and micro-fauna in C. camphora forest was higher than in other forests and the vertical distribution of soil meso- and micro-fauna in near-nature forest was relatively homogeneous in four layers. Density-group index was ranked as: near-nature forest (6.953)> C. camphora forest (6.351)> Platanus forest (6.313)>M. glyptostroboides forest (5.910). The community diversity of soil fauna in each vegetation type could be displayed preferably by this index. It could be inferred through redundancy analysis (RDA) that the soil bulk density, organic matter and total nitrogen were the main environmental factors influencing soil meso- and micro-fauna community structure in urban forest. The positive correlations occurred between the individual number of Arcari, Enchytraeidae and soil organic matter and total nitrogen, as well as between the individual number of Diptera larvae, Rotatoria and soil water content.

  1. Nutrient additions to a tropical rain forest drive substantial soil carbon dioxide losses to the atmosphere

    OpenAIRE

    Cleveland, Cory C.; Townsend, Alan R.

    2006-01-01

    Terrestrial biosphere–atmosphere carbon dioxide (CO2) exchange is dominated by tropical forests, where photosynthetic carbon (C) uptake is thought to be phosphorus (P)-limited. In P-poor tropical forests, P may also limit organic matter decomposition and soil C losses. We conducted a field-fertilization experiment to show that P fertilization stimulates soil respiration in a lowland tropical rain forest in Costa Rica. In the early wet season, when soluble organic matter inputs to soil are hig...

  2. Advances of study on atmospheric methane oxidation (consumption) in forest soil

    Institute of Scientific and Technical Information of China (English)

    WANG Chen-rui; SHI Yi; YANG Xiao-ming; WU Jie; YUE Jin

    2003-01-01

    Next to CO2, methane (CH4) is the second important contributor to global warming in the atmosphere and global atmospheric CH4 budget depends on both CH4 sources and sinks. Unsaturated soil is known as a unique sink for atmospheric CH4 in terrestrial ecosystem. Many comparison studies proved that forest soil had the biggest capacity of oxidizing atmospheric CH4 in various unsaturated soils. However, up to now, there is not an overall review in the aspect of atmospheric CH4 oxidation (consumption) in forest soil. This paper analyzed advances of studies on the mechanism of atmospheric CH4 oxidation, and related natural factors (Soil physical and chemical characters, temperature and moisture, ambient main greenhouse gases concentrations, tree species, and forest fire) and anthropogenic factors (forest clear-cutting and thinning, fertilization, exogenous aluminum salts and atmospheric deposition, adding biocides, and switch of forest land use) in forest soils. It was believed that CH4 consumption rate by forest soil was limited by diffusion and sensitive to changes in water status and temperature of soil. CH4 oxidation was also particularly sensitive to soil C/N, Ambient CO2, CH4 and N2O concentrations, tree species and forest fire. In most cases, anthropogenic disturbances will decrease atmospheric CH4 oxidation, thus resulting in the elevating of atmospheric CH4. Finally, the author pointed out that our knowledge of atmospheric CH4 oxidation (consumption) in forest soil was insufficient. In order to evaluate the contribution of forest soils to atmospheric CH4 oxidation and the role of forest played in the process of global environmental change, and to forecast the trends of global warming exactly, more researchers need to studies further on CH4 oxidation in various forest soils of different areas.

  3. Improvement of CBR and compaction characteristics of bauxite rich dispersive soils available in pakistan: a case study of khushab soil

    International Nuclear Information System (INIS)

    Batool, S.

    2016-01-01

    Dispersion of dispersive soil occurs when it comes in contact with water and clay particles deflocculate and disperse away from each other. Thus dispersive soils undergo erosion under low seepage velocity leading to instability problems of slopes and earth retaining structures. The amount of dispersion depends upon the mineralogy and geochemistry of clayey soil as well as the dissolved salts of the pore fluid. The dispersivity of the soil mainly depends on the amount of exchangeable sodium present in its formation. Under saturated conditions, the attractive forces are less than the repulsive forces and this will help the particles to disperse and go into colloidal suspension. The use of chemical stabilizers such as lime and cement to bind the clay particles and reduce the dispersivity of soil and to improve the compaction and CBR characteristics of bauxite rich dispersive soil present in Khushab district have been studied in this research. Soil behavior was studied after addition of 2%, 4%, 6% and 8% Lime and Cement, at optimum level of 6% for Lime and Cement; it has been observed that the CBR and compaction characteristics of Khushab soil have been improved. (author)

  4. Ecological impacts of tropical forest fragmentation: how consistent are patterns in species richness and nestedness?

    Science.gov (United States)

    Hill, Jane K; Gray, Michael A; Khen, Chey Vun; Benedick, Suzan; Tawatao, Noel; Hamer, Keith C

    2011-11-27

    Large areas of tropical forest now exist as remnants scattered across agricultural landscapes, and so understanding the impacts of forest fragmentation is important for biodiversity conservation. We examined species richness and nestedness among tropical forest remnants in birds (meta-analysis of published studies) and insects (field data for fruit-feeding Lepidoptera (butterflies and moths) and ants). Species-area relationships were evident in all four taxa, and avian and insect assemblages in remnants typically were nested subsets of those in larger areas. Avian carnivores and nectarivores and predatory ants were more nested than other guilds, implying that the sequential loss of species was more predictable in these groups, and that fragmentation alters the trophic organization of communities. For butterflies, the ordering of fragments to achieve maximum nestedness was by fragment area, suggesting that differences among fragments were driven mainly by extinction. In contrast for moths, maximum nestedness was achieved by ordering species by wing length; species with longer wings (implying better dispersal) were more likely to occur at all sites, including low diversity sites, suggesting that differences among fragments were driven more strongly by colonization. Although all four taxa exhibited high levels of nestedness, patterns of species turnover were also idiosyncratic, and thus even species-poor sites contributed to landscape-scale biodiversity, particularly for insects.

  5. Testing Dragonflies as Species Richness Indicators in a Fragmented Subtropical Atlantic Forest Environment.

    Science.gov (United States)

    Renner, S; Sahlén, G; Périco, E

    2016-06-01

    We surveyed 15 bodies of water among remnants of the Atlantic Forest biome in southern Brazil for adult dragonflies and damselflies to test whether an empirical selection method for diversity indicators could be applied in a subtropical ecosystem, where limited ecological knowledge on species level is available. We found a regional species pool of 34 species distributed in a nested subset pattern with a mean of 11.2 species per locality. There was a pronounced difference in species composition between spring, summer, and autumn, but no differences in species numbers between seasons. Two species, Homeoura chelifera (Selys) and Ischnura capreolus (Hagen), were the strongest candidates for regional diversity indicators, being found only at species-rich localities in our surveyed area and likewise in an undisturbed national forest reserve, serving as a reference site for the Atlantic Forest. Using our selection method, we found it possible to obtain a tentative list of diversity indicators without having detailed ecological information of each species, providing a reference site is available for comparison. The method thus allows for indicator species to be selected in blanco from taxonomic groups that are little known. We hence argue that Odonata can already be incorporated in ongoing assessment programs in the Neotropics, which would also increase the ecological knowledge of the group and allow extrapolation to other taxa.

  6. Relative abundance and species richness of cerambycid beetles in partial cut and uncut bottomland hardwood forests

    Science.gov (United States)

    Newell, P.; King, S.

    2009-01-01

    Partial cutting techniques are increasingly advocated and used to create habitat for priority wildlife. However, partial cutting may or may not benefit species dependent on deadwood; harvesting can supplement coarse woody debris in the form of logging slash, but standing dead trees may be targeted for removal. We sampled cerambycid beetles during the spring and summer of 2006 and 2007 with canopy malaise traps in 1- and 2-year-old partial cut and uncut bottomland hardwood forests of Louisiana. We captured a total of 4195 cerambycid beetles representing 65 species. Relative abundance was higher in recent partial cuts than in uncut controls and with more dead trees in a plot. Total species richness and species composition were not different between treatments. The results suggest partial cuts with logging slash left on site increase the abundance of cerambycid beetles in the first few years after partial cutting and that both partial cuts and uncut forest should be included in the bottomland hardwood forest landscape.

  7. [Microelement contents of litter, soil fauna and soil in Pinus koraiensis and broad-leaved mixed forest].

    Science.gov (United States)

    Yin, Xiu-qin; Li, Jin-xia; Dong, Wei-hua

    2007-02-01

    The analysis on the Mn, Zn and Cu contents of litter, soil fauna and soil in Pinus korazenszis and broad-leaved mixed forest in Liangshui Natural Reserve of Xiaoxing' an Mountains showed that the test microelement contents in the litter, soil fauna and soil all followed the sequence of Mn > Zn > Cu, but varied with these environmental components, being in the sequence of soil > litter > soil fauna for Mn, soil fauna > litter and soil for Zn, and soil fauna > soil > litter for Cu. The change range of test microelement contents in litter was larger in broad-leaved forest than in coniferous forest. Different soil fauna differed in their microelement-enrichment capability, e. g. , earthworm, centipede, diplopod had the highest content of Mn, Zn and Cu, respectively. The contents of test microelements in soil fauna had significant correlations with their environmental background values, litter decomposition rate, food habit of soil fauna, and its absorbing selectivity and enrichment to microelements. The microelements contained in 5-20 cm soil layer were more than those in 0-5 cm soil layer, and their dynamics differed in various soil layers.

  8. Influence of drainage status on soil and water chemistry, litter decomposition and soil respiration in central Amazonian forests on sandy soils

    NARCIS (Netherlands)

    Berton Zanchi, F.; Waterloo, M.J.; Dolman, A.J.; Groenendijk, M.; Kruijt, B.

    2011-01-01

    Central Amazonian rainforest landscape supports a mosaic of tall terra firme rainforest and ecotone campinarana, riparian and campina forests, reflecting topography-induced variations in soil, nutrient and drainage conditions. Spatial and temporal variations in litter decomposition, soil and

  9. Soil Respiration Declines Following Beetle - Induced Forest Mortality in a Lodgepole Pine Forest

    Science.gov (United States)

    Borkhuu, B.; Peckham, S. D.; Norton, U.; Ewers, B. E.; Pendall, E.

    2014-12-01

    Lodgepole pine (Pinus contorta var. latifolia) forests in northern Colorado and southeast Wyoming have been undergoing a major mortality event owing to mountain pine beetle (Dendroctonus ponderosae) infestation since 2007. We studied biotic and abiotic drivers of growing season soil respiration in four mature stands experiencing different levels of mortality between 2008 and 2012 in the Medicine Bow Mountains, southeastern Wyoming, USA. For five years, beetle infestation significantly altered forest structure. Stand mortality was 30% and more than 80% in stands with the lowest and highest mortality, respectively. Understory vegetation cover increased by 50% for five years following beetle infestation. Needlefall was increased by more than 50% during first two years of beetle infestation compared to the pre-disturbance period. We did not observe an immediate increase in soil respiration following beetle infestation as suggested by some researchers. Soil respiration rates in midsummer ranged from 1.4 ± 0.1 μmol m-2 s-1 in stands with highest mortality to 3.1 ± 0.2 μmol m-2s-1 in uninfested stand. Live tree basal area was the dominant factor controlling soil respiration, explaining more than 60% of the interannual and spatial variations in response to the disturbance. In addition, soil respiration was significantly correlated with fine root biomass, which explained 55% of variations, providing strong evidence that autotrophic respiration dominated the forest soil respiration flux. Furthermore, the seasonality of soil respiration was controlled mainly by mean monthly precipitation and mid-day photosynthetically active radiation. Each factor predicted from 30% to 50% of seasonal soil respiration variability with the highest correlation coefficients in stand with the lowest mortality. Our results clearly indicate that the reduction of photosynthesis in trees over the infestation period significantly reduced soil respiration. The remaining activity in dead stands may

  10. Changes in plant species richness induce functional shifts in soil nematode communities in experimental grassland.

    Directory of Open Access Journals (Sweden)

    Nico Eisenhauer

    Full Text Available Changes in plant diversity may induce distinct changes in soil food web structure and accompanying soil feedbacks to plants. However, knowledge of the long-term consequences of plant community simplification for soil animal food webs and functioning is scarce. Nematodes, the most abundant and diverse soil Metazoa, represent the complexity of soil food webs as they comprise all major trophic groups and allow calculation of a number of functional indices.We studied the functional composition of nematode communities three and five years after establishment of a grassland plant diversity experiment (Jena Experiment. In response to plant community simplification common nematode species disappeared and pronounced functional shifts in community structure occurred. The relevance of the fungal energy channel was higher in spring 2007 than in autumn 2005, particularly in species-rich plant assemblages. This resulted in a significant positive relationship between plant species richness and the ratio of fungal-to-bacterial feeders. Moreover, the density of predators increased significantly with plant diversity after five years, pointing to increased soil food web complexity in species-rich plant assemblages. Remarkably, in complex plant communities the nematode community shifted in favour of microbivores and predators, thereby reducing the relative abundance of plant feeders after five years.The results suggest that species-poor plant assemblages may suffer from nematode communities detrimental to plants, whereas species-rich plant assemblages support a higher proportion of microbivorous nematodes stimulating nutrient cycling and hence plant performance; i.e. effects of nematodes on plants may switch from negative to positive. Overall, food web complexity is likely to decrease in response to plant community simplification and results of this study suggest that this results mainly from the loss of common species which likely alter plant-nematode interactions.

  11. Aspen increase soil moisture, nutrients, organic matter and respiration in Rocky Mountain forest communities.

    Science.gov (United States)

    Buck, Joshua R; St Clair, Samuel B

    2012-01-01

    Development and change in forest communities are strongly influenced by plant-soil interactions. The primary objective of this paper was to identify how forest soil characteristics vary along gradients of forest community composition in aspen-conifer forests to better understand the relationship between forest vegetation characteristics and soil processes. The study was conducted on the Fishlake National Forest, Utah, USA. Soil measurements were collected in adjacent forest stands that were characterized as aspen dominated, mixed, conifer dominated or open meadow, which includes the range of vegetation conditions that exist in seral aspen forests. Soil chemistry, moisture content, respiration, and temperature were measured. There was a consistent trend in which aspen stands demonstrated higher mean soil nutrient concentrations than mixed and conifer dominated stands and meadows. Specifically, total N, NO(3) and NH(4) were nearly two-fold higher in soil underneath aspen dominated stands. Soil moisture was significantly higher in aspen stands and meadows in early summer but converged to similar levels as those found in mixed and conifer dominated stands in late summer. Soil respiration was significantly higher in aspen stands than conifer stands or meadows throughout the summer. These results suggest that changes in disturbance regimes or climate scenarios that favor conifer expansion or loss of aspen will decrease soil resource availability, which is likely to have important feedbacks on plant community development.

  12. Spatial and vertical distribution of mercury in upland forest soils across the northeastern United States

    International Nuclear Information System (INIS)

    Richardson, Justin B.; Friedland, Andrew J.; Engerbretson, Teresa R.; Kaste, James M.; Jackson, Brian P.

    2013-01-01

    Assessing current Hg pools in forest soils of the northeastern U.S. is important for monitoring changes in Hg cycling. The forest floor, upper and lower mineral horizons were sampled at 17 long-term upland forest sites across the northeastern U.S. in 2011. Forest floor Hg concentration was similar across the study region (274 ± 13 μg kg −1 ) while Hg amount at northern sites (39 ± 6 g ha −1 ) was significantly greater than at western sites (11 ± 4 g ha −1 ). Forest floor Hg was correlated with soil organic matter, soil pH, latitude and mean annual precipitation and these variables explained approximately 70% of the variability when multiple regressed. Mercury concentration and amount in the lower mineral soil was correlated with Fe, soil organic matter and latitude, corresponding with Bs horizons of Spodosols (Podzols). Our analysis shows the importance of regional and soil properties on Hg accumulation in forest soils. -- Highlights: •Mercury in the forest floor and mineral soil was quantified at 17 sites. •Concentrations and amounts were regressed with regional factors and soil properties. •Forest floor Hg was most explained by soil organic matter, pH, and precipitation. •Mineral soil Hg was explained by latitude, Fe concentration, and soil organic matter. •Mineral soil Hg was greatest in Bs horizons of Spodosols due to podzolization. -- Forest floor Hg was correlated with soil organic matter, pH, latitude, and mean annual precipitation. Mineral soil Hg was greatest in Bs horizons of Spodosols

  13. CHANGES IN SOIL MACROFAUNA IN AGROECOSYSTEMS DERIVED FROM LOW DECIDUOUS TROPICAL FOREST ON LEPTOSOLS FROM KARSTIC ZONES

    Directory of Open Access Journals (Sweden)

    Francisco Bautista

    2009-02-01

    Full Text Available In Yucatan Mexico the method of slash and burn is used for the establishment of pastures. Pastures are developed for 15 to 20 years, no more because weed control is too expensive. The impact of these practices on soil macrofauna had not been evaluated. Because of its wide distribution, diverse habits and high sensitivity to disturbance, soil macrofauna is considered a valuable indicator of soil health, allowing monitoring of soil sustainability. We studied soil macrofauna communities in low deciduous tropical forest and four livestock agroecosystems with increasing management-derived disturbance including a silvopastoral system, Taiwan grass (Cynodon nlemfuensis and Star grass (Pennisetum purpureum pastures in order to describe community structure across systems, and evaluate disturbance sensitivity of taxonomical groups to detect taxa with potential use as biological indicators of soil health or degradation. Pitfall traps were used at each of the systems to sample soil macrofauna. We estimate their taxonomical abundance, biomass, richness (order, morphospecies, diversity, dominance and response to disturbance on agroecosystems and the forest. We found 133 macrofauna morphospecies of 15 taxa. Groups with more individuals were: Hymenoptera (64.97%, Coleoptera (22.68%, and Orthoptera (3.91%.  Agroecosystem of two-year old Taiwan-grass pasture (TP2 had the highest macrofauna abundances, biomass and richness, low diversity, and a non-homogeneous distribution of individuals among species; in contrast, silvopastoral system (SP, had low abundance and biomass, the lowest specific richness, high diversity and a homogeneous distribution of individuals among species. The discriminant analysis revealed that the agroecosystems and the forest serve to predict the macrofauna communities, since they have particular or typical soil macrofauna. The cases (sampled points with a correct assignation by agroecosystems were: Forest (70%, Sivopastoral system (70

  14. Soil Organic Matter Stabilization via Mineral Interactions in Forest Soils with Varying Saturation Frequency

    Science.gov (United States)

    Possinger, A. R.; Inagaki, T.; Bailey, S. W.; Kogel-Knabner, I.; Lehmann, J.

    2017-12-01

    Soil carbon (C) interaction with minerals and metals through surface adsorption and co-precipitation processes is important for soil organic C (SOC) stabilization. Co-precipitation (i.e., the incorporation of C as an "impurity" in metal precipitates as they form) may increase the potential quantity of mineral-associated C per unit mineral surface compared to surface adsorption: a potentially important and as yet unaccounted for mechanism of C stabilization in soil. However, chemical, physical, and biological characterization of co-precipitated SOM as such in natural soils is limited, and the relative persistence of co-precipitated C is unknown, particularly under dynamic environmental conditions. To better understand the relationships between SOM stabilization via organometallic co-precipitation and environmental variables, this study compares mineral-SOM characteristics across a forest soil (Spodosol) hydrological gradient with expected differences in co-precipitation of SOM with iron (Fe) and aluminum (Al) due to variable saturation frequency. Soils were collected from a steep, well-drained forest soil transect with low, medium, and high frequency of water table intrusion into surface soils (Hubbard Brook Experimental Forest, Woodstock, NH). Lower saturation frequency soils generally had higher C content, C/Fe, C/Al, and other indicators of co-precipitation interactions resulting from SOM complexation, transport, and precipitation, an important process of Spodosol formation. Preliminary Fe X-ray Absorption Spectroscopic (XAS) characterization of SOM and metal chemistry in low frequency profiles suggest co-precipitation of SOM in the fine fraction (soils showed greater SOC mineralization per unit soil C for low saturation frequency (i.e., higher co-precipitation) soils; however, increased mineralization may be attributed to non-mineral associated fractions of SOM. Further work to identify the component of SOM contributing to rapid mineralization using 13C

  15. LBA-ECO ND-11 Soil Properties of Forested Headwater Catchments, Mato Grosso, Brazil

    Data.gov (United States)

    National Aeronautics and Space Administration — The results of the analysis of soil chemical parameters, texture, and color are reported for 185 georeferenced soil profile sample points over four forested...

  16. Spatial variability of microbial richness and diversity and relationships with soil organic carbon, texture and structure across an agricultural field

    DEFF Research Database (Denmark)

    Naveed, Muhammad; Herath, Lasantha; Møldrup, Per

    2016-01-01

    Highlights •Bacterial richness and Shannon diversity showed strong spatial autocorrelations. •Fungal richness and Shannon diversity did not show any clear spatial autocorrelations. •Ratio of clay to organic carbon was found a best predictor of bacterial richness and diversities. •Soil water...

  17. Transforming Pinus pinaster forest to recreation site: preliminary effects on LAI, some forest floor, and soil properties.

    Science.gov (United States)

    Öztürk, Melih; Bolat, İlyas

    2014-04-01

    This study investigates the effects of forest transformation into recreation site. A fragment of a Pinus pinaster plantation forest was transferred to a recreation site in the city of Bartın located close to the Black Sea coast of northwestern Turkey. During the transformation, some of the trees were selectively removed from the forest to generate more open spaces for the recreationists. As a result, Leaf Area Index (LAI) decreased by 0.20 (about 11%). Additionally, roads and pathways were introduced into the site together with some recreational equipment sealing parts of the soil surface. Consequently, forest environment was altered with a semi-natural landscape within the recreation site. The purpose of this study is to assess the effects of forest transformation into recreation site particularly in terms of the LAI parameter, forest floor, and soil properties. Preliminary monitoring results indicate that forest floor biomass is reduced by 26% in the recreation site compared to the control site. Soil temperature is increased by 15% in the recreation site where selective removal of trees expanded the gaps allowing more light transmission. On the other hand, the soil bulk density which is an indicator of soil compaction is unexpectedly slightly lower in the recreation site. Organic carbon (C(org)) and total nitrogen (N(total)) together with the other physical and chemical parameter values indicate that forest floor and soil have not been exposed to much disturbance. However, subsequent removal of trees that would threaten the vegetation, forest floor, and soil should not be allowed. The activities of the recreationists are to be concentrated on the paved spaces rather than soil surfaces. Furthermore, long-term monitoring and management is necessary for both the observation and conservation of the site.

  18. Soil Quality of Restinga Forest: Organic Matter and Aluminum Saturation

    Science.gov (United States)

    Rodrigues Almeida Filho, Jasse; Casagrande, José Carlos; Martins Bonilha, Rodolfo; Soares, Marcio Roberto; Silva, Luiz Gabriel; Colato, Alexandre

    2013-04-01

    The restinga vegetation (sand coastal plain vegetation) consists of a mosaic of plant communities, which are defined by the characteristics of the substrates, resulting from the type and age of the depositional processes. This mosaic complex of vegetation types comprises restinga forest in advanced (high restinga) and medium regeneration stages (low restinga), each with particular differentiating vegetation characteristics. Of all ecosystems of the Atlantic Forest, restinga is the most fragile and susceptible to anthropic disturbances. The purpose of this study was evaluating the organic matter and aluminum saturation effects on soil quality index (SQI). Two locations were studied: State Park of the Serra do Mar, Picinguaba, in the city of Ubatuba (23°20' e 23°22' S / 44°48' e 44°52' W), and State Park of Cardoso Island in the city of Cananéia (25°03'05" e 25°18'18" S / 47°53'48" e 48° 05'42" W). The soil samples were collect at a depth of 0-10 cm, where concentrate 70% of vegetation root system. Was studied an additive model to evaluate soil quality index. The shallow root system development occurs due to low calcium levels, whose disability limits their development, but also can reflect on delay, restriction or even in the failure of the development vegetation. The organic matter is kept in the soil restinga ecosystem by high acidity, which reduces the decomposition of soil organic matter, which is very poor in nutrients. The base saturation, less than 10, was low due to low amounts of Na, K, Ca and Mg, indicating low nutritional reserve into the soil, due to very high rainfall and sandy texture, resulting in high saturation values for aluminum. Considering the critical threshold to 3% organic matter and for aluminum saturation to 40%, the IQS ranged from 0.95 to 0.1 as increased aluminum saturation and decreased the soil organic matter, indicating the main limitation to the growth of plants in this type of soil, when deforested.

  19. Clay minerals, metallic oxides and oxy-hydroxides and soil organic carbon distribution within soil aggregates in temperate forest soils

    Science.gov (United States)

    Gartzia-Bengoetxea, Nahia; Fernández-Ugalde, Oihane; Virto, Iñigo; Arias-González, Ander

    2017-04-01

    Soil mineralogy is of primary importance for key environmental services provided by soils like carbon sequestration. However, current knowledge on the effects of clay mineralogy on soil organic carbon (SOC) stabilization is based on limited and conflicting data. In this study, we investigated the relationship between clay minerals, metallic oxides and oxy-hydroxides and SOC distribution within soil aggregates in mature Pinus radiata D.Don forest plantations. Nine forest stands located in the same geographical area of the Basque Country (North of Spain) were selected. These stands were planted on different parent material (3 on each of the following: sandstone, basalt and trachyte). There were no significant differences in climate and forest management among them. Moreover, soils under these plantations presented similar content of clay particles. We determined bulk SOC storage, clay mineralogy, the content of Fe-Si-Al-oxides and oxyhydroxides and the distribution of organic C in different soil aggregate sizes at different soil depths (0-5 cm and 5-20 cm). The relationship between SOC and abiotic factors was investigated using a factor analysis (PCA) followed by stepwise regression analysis. Soils developed on sandstone showed significantly lower concentration of SOC (29 g C kg-1) than soils developed on basalts (97 g C kg-1) and trachytes (119 g C kg-1). The soils on sandstone presented a mixed clay mineralogy dominated by illite, with lesser amounts of hydroxivermiculite, hydrobiotite and kaolinite, and a total absence of interstratified chlorite/vermiculite. In contrast, the major crystalline clay mineral identified in the soils developed on volcanic rocks was interstratified chlorite/vermiculite. Nevertheless, no major differences were observed between basaltic and trachytic soils in the clay mineralogy. The selective extraction of Fe showed that the oxalate extractable iron was significantly lower in soils on sandstone (3.7%) than on basalts (11.2%) and

  20. Comparison of the Chemical Properties of Forest Soil from the Silesian Beskid, Poland

    Directory of Open Access Journals (Sweden)

    Maria Zołotajkin

    2014-01-01

    Full Text Available There is spruce forests degradation observed in the Silesian Beskid. The aim of the work was the assessment of parameters diversifying organic layers of soils in two forest areas: degraded and healthy spruce forests of Silesian Beskid. 23 soil samples were collected from two fields—14 soil samples from a degraded forest and 9 soil samples from a forest, where pandemic dying of spruce is not observed. Implementation of hierarchical clustering to experimental data analysis allowed drawing a conclusion that the two forest areas vary significantly in terms of content of aluminium extracted with solutions of barium chloride (Alexch, sodium diphosphate (Alpyr, and pHKCl and in the amount of humus in soil.

  1. Tree species richness, diversity, and regeneration status in different oak (Quercus spp. dominated forests of Garhwal Himalaya, India

    Directory of Open Access Journals (Sweden)

    Sushma Singh

    2016-09-01

    Full Text Available Himalayan forests are dominated by different species of oaks (Quercus spp. at different altitudes. These oaks are intimately linked with hill agriculture as they protect soil fertility, watershed, and local biodiversity. They also play an important role in maintaining ecosystem stability. This work was carried out to study the diversity and regeneration status of some oak forests in Garhwal Himalaya, India. A total of 18 tree species belonging to 16 genera and 12 families were reported from the study area. Species richness varied for trees (4–7, saplings (3–10, and seedlings (2–6. Seedling and sapling densities (Ind/ha varied between 1,376 Ind/ha and 9,600 Ind/ha and 167 Ind/ha and 1,296 Ind/ha, respectively. Species diversity varied from 1.27 to 1.86 (trees, from 0.93 to 3.18 (saplings, and from 0.68 to 2.26 (seedlings. Total basal area (m2/ha of trees and saplings was 2.2–87.07 m2/ha and 0.20–2.24 m2/ha, respectively, whereas that of seedlings varied from 299 cm2/ha to 8,177 cm2/ha. Maximum tree species (20–80% had “good” regeneration. Quercus floribunda, the dominant tree species in the study area, showed “poor” regeneration, which is a matter of concern, and therefore, proper management and conservation strategies need to be developed for maintenance and sustainability of this oak species along with other tree species that show poor or no regeneration.

  2. Influences of forest usage on the remainder mass and soil

    Directory of Open Access Journals (Sweden)

    Alexey Rosabal Quintana

    2017-12-01

    Full Text Available The work was carried out in the handling area "Los Números" belonging to the mountainous ecosystem of the Silvicole Unit Guisa, with the objective of determining the damages to the soil and the remainder mass to the forest usage to give execution to this objective the transcept method was used where punctual observations for every 20 meters were made,, parcels rose and a striped florístic was elaborated from that of a total of 3 302 trees, they were downed 339 which caused the death of 1 313, causing that 7.7% of the usage area was impacted by hints or clearings.

  3. Effects of annual and interannual environmental variability on soil fungi associated with an old-growth, temperate hardwood forest.

    Science.gov (United States)

    Burke, David J

    2015-06-01

    Seasonal and interannual variability in temperature, precipitation and chemical resources may regulate fungal community structure in forests but the effect of such variability is still poorly understood. In this study, I examined changes in fungal communities over two years and how these changes were correlated to natural variation in soil conditions. Soil cores were collected every month for three years from permanent plots established in an old-growth hardwood forest, and molecular methods were used to detect fungal species. Species richness and diversity were not consistent between years with richness and diversity significantly affected by season in one year but significantly affected by depth in the other year. These differences were associated with variation in late winter snow cover. Fungal communities significantly varied by plot location, season and depth and differences were consistent between years but fungal species within the community were not consistent in their seasonality or in their preference for certain soil depths. Some fungal species, however, were found to be consistently correlated with soil chemistry across sampled years. These results suggest that fungal community changes reflect the behavior of the individual species within the community pool and how those species respond to local resource availability. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. Contribution of fine tree roots to the silicon cycle in a temperate forest ecosystem developed on three soil types

    Science.gov (United States)

    Turpault, Marie-Pierre; Calvaruso, Christophe; Kirchen, Gil; Redon, Paul-Olivier; Cochet, Carine

    2018-04-01

    .5-2.0 times higher in the Si-rich DC compared to the Si-poor RL. In terms of the DSi budget, DSi production was large in the three plots in the forest floor (9.9 to 12.7 kg ha-1 yr-1), as well as in the superficial soil layer (5.3 to 14.5 kg ha-1 yr-1), and decreased with soil depth. An immobilization of DSi was even observed at 90 cm depth in plot DC (-1.7 kg ha-1 yr-1). The amount of Si leached from the soil profile was relatively low compared to the annual uptake by trees (13 % in plot DC to 29 % in plot RL). The monthly measurements demonstrated that the seasonal dynamics of the DSi budget were mainly linked to biological activity. Notably, the peak of dissolved Si production in the superficial soil layer occurred during winter and probably resulted from fine-root decomposition. Our study reveals that biological processes, particularly those involving fine roots, play a predominant role in the Si cycle in temperate forest ecosystems, while the geochemical processes appear to be limited.

  5. Natural 15N abundance of soil N pools and N2O reflect the nitrogen dynamics of forest soils

    DEFF Research Database (Denmark)

    Pörtl, K.; Zechmeister-Boltenstern, S.; Wanek, W.

    2007-01-01

    Natural N-15 abundance measurements of ecosystem nitrogen (N) pools and N-15 pool dilution assays of gross N transformation rates were applied to investigate the potential of delta N-15 signatures of soil N pools to reflect the dynamics in the forest soil N cycle. Intact soil cores were collected...

  6. Determining soil hydrologic characteristics on a remote forest watershed by continuous monitoring of soil water pressures, rainfall and runoff.

    Science.gov (United States)

    L.R. Ahuja; S. A. El-Swaify

    1979-01-01

    Continuous monitoring of soil-water pressures, rainfall and runoff under natural conditions was tested as a technique for determining soil hydrologic characteristics of a remote forest watershed plot. A completely battery-powered (and thus portable) pressure transducer–scanner–recorder system was assembled for monitoring of soil-water pressures in...

  7. Effects of Soil Texture on Belowground Carbon and Nutrient Storage in a Lowland Amazonian Forest Ecosystem.

    Science.gov (United States)

    Whendee L. Silver; Jason Neff; Megan McGroddy; Ed Veldkamp; Michael Keller; Raimundo Cosme

    2000-01-01

    Soil texture plays a key role in belowground C storage in forest ecosystems and strongly influences nutrient availability and retention, particularly in highly weathered soils. We used field data and the Century ecosystem model to explore the role of soil texture in belowground C storage, nutrient pool sizes, and N fluxes in highly weathered soils in an Amazonian...

  8. Calcium weathering in forested soils and the effedt of different tree species

    NARCIS (Netherlands)

    Dijkstra, F.A.; Breemen, van N.; Jongmans, A.G.; Davies, G.R.; Likens, G.E.

    2003-01-01

    Soil weathering can be an important mechanism to neutralize acidity in forest soils. Tree species may differ in their effect on or response to soil weathering. We used soil mineral data and the natural strontium isotope ratio Sr-87/Sr-86 as a tracer to identify the effect of tree species on the Ca

  9. Tree species, spatial heterogeneity, and seasonality drive soil fungal abundance, richness, and composition in Neotropical rainforests.

    Science.gov (United States)

    Kivlin, Stephanie N; Hawkes, Christine V

    2016-12-01

    Tropical ecosystems remain poorly understood and this is particularly true for belowground soil fungi. Soil fungi may respond to plant identity when, for example, plants differentially allocate resources belowground. However, spatial and temporal heterogeneity in factors such as plant inputs, moisture, or nutrients can also affect fungal communities and obscure our ability to detect plant effects in single time point studies or within diverse forests. To address this, we sampled replicated monocultures of four tree species and secondary forest controls sampled in the drier and wetter seasons over 2 years. Fungal community composition was primarily related to vegetation type and spatial heterogeneity in the effects of vegetation type, with increasing divergence partly reflecting greater differences in soil pH and soil moisture. Across wetter versus drier dates, fungi were 7% less diverse, but up to four-fold more abundant. The combined effects of tree species and seasonality suggest that predicted losses of tropical tree diversity and intensification of drought have the potential to cascade belowground to affect both diversity and abundance of tropical soil fungi. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  10. Changes in soil moisture drive soil methane uptake along a fire regeneration chronosequence in a eucalypt forest landscape.

    Science.gov (United States)

    Fest, Benedikt; Wardlaw, Tim; Livesley, Stephen J; Duff, Thomas J; Arndt, Stefan K

    2015-11-01

    Disturbance associated with severe wildfires (WF) and WF simulating harvest operations can potentially alter soil methane (CH4 ) oxidation in well-aerated forest soils due to the effect on soil properties linked to diffusivity, methanotrophic activity or changes in methanotrophic bacterial community structure. However, changes in soil CH4 flux related to such disturbances are still rarely studied even though WF frequency is predicted to increase as a consequence of global climate change. We measured in-situ soil-atmosphere CH4 exchange along a wet sclerophyll eucalypt forest regeneration chronosequence in Tasmania, Australia, where the time since the last severe fire or harvesting disturbance ranged from 9 to >200 years. On all sampling occasions, mean CH4 uptake increased from most recently disturbed sites (9 year) to sites at stand 'maturity' (44 and 76 years). In stands >76 years since disturbance, we observed a decrease in soil CH4 uptake. A similar age dependency of potential CH4 oxidation for three soil layers (0.0-0.05, 0.05-0.10, 0.10-0.15 m) could be observed on incubated soils under controlled laboratory conditions. The differences in soil CH4 uptake between forest stands of different age were predominantly driven by differences in soil moisture status, which affected the diffusion of atmospheric CH4 into the soil. The observed soil moisture pattern was likely driven by changes in interception or evapotranspiration with forest age, which have been well described for similar eucalypt forest systems in south-eastern Australia. Our results imply that there is a large amount of variability in CH4 uptake at a landscape scale that can be attributed to stand age and soil moisture differences. An increase in severe WF frequency in response to climate change could potentially increase overall forest soil CH4 sinks. © 2015 John Wiley & Sons Ltd.

  11. Microbial physiology and soil CO2 efflux after 9 years of soil warming in a temperate forest - no indications for thermal adaptations.

    Science.gov (United States)

    Schindlbacher, Andreas; Schnecker, Jörg; Takriti, Mounir; Borken, Werner; Wanek, Wolfgang

    2015-11-01

    Thermal adaptations of soil microorganisms could mitigate or facilitate global warming effects on soil organic matter (SOM) decomposition and soil CO2 efflux. We incubated soil from warmed and control subplots of a forest soil warming experiment to assess whether 9 years of soil warming affected the rates and the temperature sensitivity of the soil CO2 efflux, extracellular enzyme activities, microbial efficiency, and gross N mineralization. Mineral soil (0-10 cm depth) was incubated at temperatures ranging from 3 to 23 °C. No adaptations to long-term warming were observed regarding the heterotrophic soil CO2 efflux (R10 warmed: 2.31 ± 0.15 μmol m(-2)  s(-1) , control: 2.34 ± 0.29 μmol m(-2)  s(-1) ; Q10 warmed: 2.45 ± 0.06, control: 2.45 ± 0.04). Potential enzyme activities increased with incubation temperature, but the temperature sensitivity of the enzymes did not differ between the warmed and the control soils. The ratio of C : N acquiring enzyme activities was significantly higher in the warmed soil. Microbial biomass-specific respiration rates increased with incubation temperature, but the rates and the temperature sensitivity (Q10 warmed: 2.54 ± 0.23, control 2.75 ± 0.17) did not differ between warmed and control soils. Microbial substrate use efficiency (SUE) declined with increasing incubation temperature in both, warmed and control, soils. SUE and its temperature sensitivity (Q10 warmed: 0.84 ± 0.03, control: 0.88 ± 0.01) did not differ between warmed and control soils either. Gross N mineralization was invariant to incubation temperature and was not affected by long-term soil warming. Our results indicate that thermal adaptations of the microbial decomposer community are unlikely to occur in C-rich calcareous temperate forest soils. © 2015 The Authors. Global Change Biology published by John Wiley & Sons Ltd.

  12. Factors of influencing dissolved organic carbon stabilization in two cambic forest soils with contrasting soil-forming processes

    Science.gov (United States)

    Kawasaki, M.; Ohte, N.; Asano, Y.; Uchida, T.; Kabeya, N.; Kim, S.

    2004-05-01

    Stabilization of Dissolved Organic Carbon (DOC) in forest soil is a major process of soil organic carbon formation. However, the factors influencing DOC stabilization are poorly understood. To clarify the factors that affect the stabilization of DOC in forest soil mantle, we measured DOC concentrations and soil properties which were DOC adsorption efficiency at two adjacent cambic forest soils with contrasting forest management histories in Tanakami Mountains, central Japan. Matsuzawa was devastated about 1,200 years ago by excessive timber use and remained denuded for a long period. Hillside restoration and reforestation work have been carried out over the last 100 years and soil loss has been reduced. Fudoji is covered with undisturbed forest (mixed stands of cypress and oaks) with developed forest soils (more than 2,600 years old). There was no apparent seasonal variation in DOC concentration in the soil solution in either catchment. In addition, there were no significant relationships between the DOC concentration, soil temperature, and new water ratio. These results indicate that temporal variation in biological activity and rainfall-runoff process have little effect on temporal variation in DOC. The vertical variation in the DOC adsorption efficiency and DOC concentration differed between Matsuzawa and Fudoji, and the highest DOC removal rate occurred at the lowest DOC adsorption efficiency in the 0 to 10-cm soil layer at Fudoji. These results suggest that DOC removal rate is independent of DOC adsorption efficiency. Below 60 cm soil depth, DOC fluxes were constant and dissolved organic Al concentrations were little or zero in either catchment. These results suggest that abiotic precipitation of DOC is a major mechanism for stabilization of DOC. Therefore, DOC content which is able to form metal complexes may be the most important factor of influencing DOC stabilization in cambic forest soil.

  13. The Redox Dynamics of Iron in a Seasonally Waterlogged Forest Soil (Chaux Forest, Eastern France) Traced with Rare Earth Element Distribution Patterns

    Science.gov (United States)

    Steinmann, M.; Floch, A. L.; Lucot, E.; Badot, P. M.

    2014-12-01

    The oxyhydroxides of iron are common soil minerals and known to control the availability of various major and trace elements essential for biogeochemical processes. We present a study from acidic natural forest soils, where reducing redox conditions due to seasonal waterlogging lead to the dissolution of Fe-oxyhydroxides, and to the release of Fe to soil water. In order to study in detail the mechanism of redox cycling of Fe, we used Rare Earth Element (REE) distribution patterns, because an earlier study has shown that they are a suitable tool to identify trace metal sources during soil reduction in wetland soils (Davranche et al., 2011). The REE patterns of soil leachates obtained with the modified 3-step BCR extraction scheme of Rauret et al., (1999) were compared with those of natural soil water. The adsorbed fractions (F1 leach), the reducible fraction of the deepest soil horizon H4 (F2 leach, 50-120 cm), and the oxidizable fractions of horizons H2 to H4 (F3 leachs, 24-120 cm) yielded REE patterns almost identical to soil water (see figure), showing that the REE and trace metal content of soil water was mainly derived from the F1 pool, and from the F2 and F3 pools of the clay mineral-rich deep soil horizons. In contrast, the F2 leach mobilized mainly Fe-oxyhydroxides associated with organic matter of the surface soil and yielded REE patterns significantly different from those of soil water. These results suggest that the trace metal content of soil water in hydromorphic soils is primarily controlled by the clay fraction of the deeper soil horizons and not by organic matter and related Fe-oxyhydroxides of the surface soil. Additional analyses are in progress in order to verify whether the REE and trace metals of the deeper soil horizons were directly derived from clay minerals or from associated Fe-oxyhydroxide coatings. Refs cited: Davranche et al. (2011), Chem. Geol. 284; Rauret et al. (1999), J. Environ. Monit. 1.

  14. [Diversity of soil nematode communities in the subalpine and alpine forests of western Sichuan, China.

    Science.gov (United States)

    Chen, Ya; Yang, Wan Qin; Wu, Fu Zhong; Yang, Fan; Lan, Li Ying; Liu, Yu Wei; Guo, Cai Hong; Tan, Bo

    2017-10-01

    In order to understand the diversity of soil nematodes in the subalpine/alpine forests of the eastern Qinghai-Tibet Plateau, soil nematodes in the primary forest, mixed forest and secondary forest of Abies faxoniana were extracted by elutriation and sugar-centrifugation method in July 2015, and the composition and structure characteristics of soil nematode communities were studied in the three forests at different altitudes. A total of 37950 soil nematodes were collected, which belonged to 20 families and 27 genera, and the mean density was 4217 ind·100 g -1 dry soil. Filenchus was the dominant genus in the primary forest, and Filenchus and Pararotylenchus in the mixed forest and secondary forest, respectively. The individual number of each dominant genus was significantly affected by forest type. All nematode individuals were classified into the four trophic groups of bacterivores, fungivores, plant-parasites and omnivore-predators. The fungivores were dominant in the primary and secondary forest and the bacterivores in the mixed forest. The number of soil nematode c-p (colonizer-persister) groups of c-p 1, c-p 2, c-p 3 and c-p 4 accounted for 6.1%, 51.1%, 30.0% and 12.7% of the total nematode abundance, respectively. The maturity index (MI), the total maturity index (∑MI) and the plant parasitic index (PPI) of soil nematodes decreased gradually with the increase of altitude. The nematode channel ratio in the mixed forest was higher than 0.5, but that in the primary forest and secondary forest was below 0.5. The forest type significantly affected the soil nematode maturity index and channel ratio, but the forest type, soil layer and their interaction had no significant effect on the diversity index. There were obvious diffe-rences in the composition, nutrient structure and energy flow channel of soil nematodes in the subalpine/alpine forests of western Sichuan, providing an important reference for understanding the function of soil nematodes in soil processes

  15. Abundance and stratification of soil macroarthropods in a Caatinga Forest in Northeast Brazil

    Directory of Open Access Journals (Sweden)

    VFP Araújo

    Full Text Available In arid and semiarid environments, seasonality usually exerts a strong influence on the composition and dynamics of the soil community. The soil macroarthropods were studied in a Caatinga forest located in the Reserva Particular do Patrimônio Natural (RPPN Fazenda Almas, São José dos Cordeiros, Paraíba, Brazil. Samples were collected during the dry and rainy seasons following the method proposed by the Tropical Soil Biology and Fertility Program (TSBF, with minor modifications. At each station, 15 soil blocks (20 × 20 × 30 cm: 12 L were extracted and divided into three layers: A (0-10 cm, B (10-20 cm, and C (20-30 cm. In the rainy and dry seasons 1,306 ± 543(se and 458 ± 212 ind.m-2 macroarthropods were found, respectively, with 35 and 18 respective taxa recorded. The abundance of individuals and taxa were significantly higher in the rainy season. Isoptera (57.8% was the most abundant taxon, followed by Hymenoptera: Formicidae (17.2%, Coleoptera larvae (7.3%, and Araneae (3.5%. In the rainy season, abundance in layer A (576 ± 138 ind.m-2 was significantly higher than that of layer C (117 ± 64 ind.m-2, but was not different from layer B (613 ± 480 ind.m-2. There was also no difference between the layer B and C abundances. In the dry season, abundance in layer B (232 ± 120 ind.m-2 was not significantly different compared to layer A (182 ± 129 ind.m-2, but was significantly higher than abundance in layer C (44 ± 35 ind.m-2. During the rainy season, layer A (34 taxa was significantly richer in taxa than layers B (19 taxa and C (11 taxa. On the other hand, during the dry season the richness of layers A (12 taxa and B (12 taxa was equal, but significantly higher than that of layer C (6 taxa. Richness of taxa and abundance were positively correlated with soil organic matter and negatively correlated with soil temperature. The community of soil macroarthropods in the area of Caatinga studied has taxonomic and functional structures that are

  16. Abundance and stratification of soil macroarthropods in a Caatinga Forest in Northeast Brazil.

    Science.gov (United States)

    Araújo, V F P; Bandeira, A G; Vasconcellos, A

    2010-10-01

    In arid and semiarid environments, seasonality usually exerts a strong influence on the composition and dynamics of the soil community. The soil macroarthropods were studied in a Caatinga forest located in the Reserva Particular do Patrimônio Natural (RPPN) Fazenda Almas, São José dos Cordeiros, Paraíba, Brazil. Samples were collected during the dry and rainy seasons following the method proposed by the Tropical Soil Biology and Fertility Program (TSBF), with minor modifications. At each station, 15 soil blocks (20 × 20 × 30 cm: 12 L) were extracted and divided into three layers: A (0-10 cm), B (10-20 cm), and C (20-30 cm). In the rainy and dry seasons 1,306 ± 543(se) and 458 ± 212 ind.m-2 macroarthropods were found, respectively, with 35 and 18 respective taxa recorded. The abundance of individuals and taxa were significantly higher in the rainy season. Isoptera (57.8%) was the most abundant taxon, followed by Hymenoptera: Formicidae (17.2%), Coleoptera larvae (7.3%), and Araneae (3.5%). In the rainy season, abundance in layer A (576 ± 138 ind.m-2) was significantly higher than that of layer C (117 ± 64 ind.m-2), but was not different from layer B (613 ± 480 ind.m-2). There was also no difference between the layer B and C abundances. In the dry season, abundance in layer B (232 ± 120 ind.m-2) was not significantly different compared to layer A (182 ± 129 ind.m-2), but was significantly higher than abundance in layer C (44 ± 35 ind.m-2). During the rainy season, layer A (34 taxa) was significantly richer in taxa than layers B (19 taxa) and C (11 taxa). On the other hand, during the dry season the richness of layers A (12 taxa) and B (12 taxa) was equal, but significantly higher than that of layer C (6 taxa). Richness of taxa and abundance were positively correlated with soil organic matter and negatively correlated with soil temperature. The community of soil macroarthropods in the area of Caatinga studied has taxonomic and functional structures that

  17. Controls of Soil Spatial Variability in a Dry Tropical Forest.

    Directory of Open Access Journals (Sweden)

    Sandeep Pulla

    Full Text Available We examined the roles of lithology, topography, vegetation and fire in generating local-scale (<1 km2 soil spatial variability in a seasonally dry tropical forest (SDTF in southern India. For this, we mapped soil (available nutrients, Al, total C, pH, moisture and texture in the top 10 cm, rock outcrops, topography, all native woody plants ≥1 cm diameter at breast height (DBH, and spatial variation in fire frequency (times burnt during the 17 years preceding soil sampling in a permanent 50-ha plot. Unlike classic catenas, lower elevation soils had lesser moisture, plant-available Ca, Cu, Mn, Mg, Zn, B, clay and total C. The distribution of plant-available Ca, Cu, Mn and Mg appeared to largely be determined by the whole-rock chemical composition differences between amphibolites and hornblende-biotite gneisses. Amphibolites were associated with summit positions, while gneisses dominated lower elevations, an observation that concurs with other studies in the region which suggest that hillslope-scale topography has been shaped by differential weathering of lithologies. Neither NO3(--N nor NH4(+-N was explained by the basal area of trees belonging to Fabaceae, a family associated with N-fixing species, and no long-term effects of fire on soil parameters were detected. Local-scale lithological variation is an important first-order control over soil variability at the hillslope scale in this SDTF, by both direct influence on nutrient stocks and indirect influence via control of local relief.

  18. Soil erosion after forest fires in the Valencia region

    Science.gov (United States)

    González-Pelayo, Óscar; Keizer, Jan Jacob; Cerdà, Artemi

    2014-05-01

    Soil erosion after forest fire is triggered by the lack of vegetation cover and the degradation of the physical, biological and chemical properties (Martí et al., 2012; Fernández et al., 2012; Guénon, 2013). Valencia region belongs to the west Mediterranean basin ("Csa", Köppen climate classification), with drought summer periods that enhance forest fire risk. The characteristics of the climate, lithology and land use history makes this region more vulnerable to soil erosion. In this area, fire recurrence is being increased since late 50s (Pausas, 2004) and post-fire erosion studies became more popular from 80's until nowadays (Cerdá and Mataix-Solera, 2009). Research in Valencia region has contributed significantly to a better understanding of the effect of spatial and temporal scale on runoff and sediment yield measurements. The main achievements concerns: a) direct measurement of erosion rates under a wide range of methodologies (natural vs simulated rainfall, open vs closed plots); from micro- to meso-plot and catchment scale in single (Rubio et al., 1994; Cerdà et al., 1995; Cerdà 1998a; 1998b; Llovet et al., 1998; Cerdà, 2001; Calvo-Cases et al., 2003; Andreu et al., 2001; Mayor et al., 2007; Cerdà and Doerr, 2008) and multiples fires (Campo et al., 2006; González-Pelayo et al., 2010a). Changes in soil properties (Sanroque et al., 1985; Rubio et al., 1997; Boix-Fayós, 1997; Gimeno-Garcia et al., 2000; Guerrero et al., 2001; Mataix-Solera et al., 2004; González-Pelayo et al., 2006; Arcenegui et al., 2008; Campo et al., 2008; Bodí et al., 2012), in post-fire vegetation patterns (Gimeno-García et al., 2007) and, studies on mitigation strategies (Bautista et al., 1996; Abad et al., 2000). b) Progress to understanding post-fire erosion mechanism and sediment movement (Boix-Fayós et al., 2005) by definition of thresholds for sediment losses; fire severity, slope angle, bedrock, rain characteristics, vegetation pattern and ecosystem resilience (Mayor

  19. Response of soil respiration to acid rain in forests of different maturity in southern China.

    Directory of Open Access Journals (Sweden)

    Guohua Liang

    Full Text Available The response of soil respiration to acid rain in forests, especially in forests of different maturity, is poorly understood in southern China despite the fact that acid rain has become a serious environmental threat in this region in recent years. Here, we investigated this issue in three subtropical forests of different maturity [i.e. a young pine forest (PF, a transitional mixed conifer and broadleaf forest (MF and an old-growth broadleaved forest (BF] in southern China. Soil respiration was measured over two years under four simulated acid rain (SAR treatments (CK, the local lake water, pH 4.5; T1, water pH 4.0; T2, water pH 3.5; and T3, water pH 3.0. Results indicated that SAR did not significantly affect soil respiration in the PF, whereas it significantly reduced soil respiration in the MF and the BF. The depressed effects on both forests occurred mostly in the warm-wet seasons and were correlated with a decrease in soil microbial activity and in fine root biomass caused by soil acidification under SAR. The sensitivity of the response of soil respiration to SAR showed an increasing trend with the progressive maturity of the three forests, which may result from their differences in acid buffering ability in soil and in litter layer. These results indicated that the depressed effect of acid rain on soil respiration in southern China may be more pronounced in the future in light of the projected change in forest maturity. However, due to the nature of this field study with chronosequence design and the related pseudoreplication for forest types, this inference should be read with caution. Further studies are needed to draw rigorous conclusions regarding the response differences among forests of different maturity using replicated forest types.

  20. Response of soil respiration to acid rain in forests of different maturity in southern China.

    Science.gov (United States)

    Liang, Guohua; Liu, Xingzhao; Chen, Xiaomei; Qiu, Qingyan; Zhang, Deqiang; Chu, Guowei; Liu, Juxiu; Liu, Shizhong; Zhou, Guoyi

    2013-01-01

    The response of soil respiration to acid rain in forests, especially in forests of different maturity, is poorly understood in southern China despite the fact that acid rain has become a serious environmental threat in this region in recent years. Here, we investigated this issue in three subtropical forests of different maturity [i.e. a young pine forest (PF), a transitional mixed conifer and broadleaf forest (MF) and an old-growth broadleaved forest (BF)] in southern China. Soil respiration was measured over two years under four simulated acid rain (SAR) treatments (CK, the local lake water, pH 4.5; T1, water pH 4.0; T2, water pH 3.5; and T3, water pH 3.0). Results indicated that SAR did not significantly affect soil respiration in the PF, whereas it significantly reduced soil respiration in the MF and the BF. The depressed effects on both forests occurred mostly in the warm-wet seasons and were correlated with a decrease in soil microbial activity and in fine root biomass caused by soil acidification under SAR. The sensitivity of the response of soil respiration to SAR showed an increasing trend with the progressive maturity of the three forests, which may result from their differences in acid buffering ability in soil and in litter layer. These results indicated that the depressed effect of acid rain on soil respiration in southern China may be more pronounced in the future in light of the projected change in forest maturity. However, due to the nature of this field study with chronosequence design and the related pseudoreplication for forest types, this inference should be read with caution. Further studies are needed to draw rigorous conclusions regarding the response differences among forests of different maturity using replicated forest types.

  1. Dominant Tree Species and Soil Type Affect the Fungal Community Structure in a Boreal Peatland Forest.

    Science.gov (United States)

    Sun, Hui; Terhonen, Eeva; Kovalchuk, Andriy; Tuovila, Hanna; Chen, Hongxin; Oghenekaro, Abbot O; Heinonsalo, Jussi; Kohler, Annegret; Kasanen, Risto; Vasander, Harri; Asiegbu, Fred O

    2016-05-01

    Boreal peatlands play a crucial role in global carbon cycling, acting as an important carbon reservoir. However, little information is available on how peatland microbial communities are influenced by natural variability or human-induced disturbances. In this study, we have investigated the fungal diversity and community structure of both the organic soil layer and buried wood in boreal forest soils using high-throughput sequencing of the internal transcribed spacer (ITS) region. We have also compared the fungal communities during the primary colonization of wood with those of the surrounding soils. A permutational multivariate analysis of variance (PERMANOVA) confirmed that the community composition significantly differed between soil types (P< 0.001) and tree species (P< 0.001). The distance-based linear models analysis showed that environmental variables were significantly correlated with community structure (P< 0.04). The availability of soil nutrients (Ca [P= 0.002], Fe [P= 0.003], and P [P= 0.003]) within the site was an important factor in the fungal community composition. The species richness in wood was significantly lower than in the corresponding soil (P< 0.004). The results of the molecular identification were supplemented by fruiting body surveys. Seven of the genera of Agaricomycotina identified in our surveys were among the top 20 genera observed in pyrosequencing data. Our study is the first, to our knowledge, fungal high-throughput next-generation sequencing study performed on peatlands; it further provides a baseline for the investigation of the dynamics of the fungal community in the boreal peatlands. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

  2. Occurrence of culturable soil fungi in a tropical moist deciduous forest Similipal Biosphere Reserve, Odisha, India.

    Science.gov (United States)

    Jena, Santanu K; Tayung, Kumanand; Rath, Chandi C; Parida, Debraj

    2015-03-01

    Similipal Biosphere Reserve (SBR) is a tropical moist deciduous forest dominated by the species Shorea robusta . To the best of our knowledge their rich biodiversity has not been explored in term of its microbial wealth. In the present investigation, soil samples were collected from ten selected sites inside SBR and studied for their physicochemical parameters and culturable soil fungal diversity. The soil samples were found to be acidic in nature with a pH ranging from of 5.1-6.0. Highest percentage of organic carbon and moisture content were observed in the samples collected from the sites, Chahala-1 and Chahala-2. The plate count revealed that fungal population ranged from 3.6 × 10 (4) -2.1 × 10 (5) and 5.1 × 10 (4) -4.7 × 10 (5) cfu/gm of soil in summer and winter seasons respectively. The soil fungus, Aspergillus niger was found to be the most dominant species and Species Important Values Index (SIVI) was 43.4 and 28.6 in summer and winter seasons respectively. Among the sites studied, highest fungal diversity indices were observed during summer in the sites, Natto-2 and Natto-1. The Shannon-Wiener and Simpson indices in these two sites were found to be 3.12 and 3.022 and 0.9425 and 0.9373 respectively. However, the highest Fisher's alpha was observed during winter in the sites Joranda, Natto-2, Chahala-1 and Natto-1 and the values were 3.780, 3.683, 3.575 and 3.418 respectively. Our investigation revealed that, fungal population was dependent on moisture and organic carbon (%) of the soil but its diversity was found to be regulated by sporulating species like Aspergillus and Penicillium.

  3. Occurrence of culturable soil fungi in a tropical moist deciduous forest Similipal Biosphere Reserve, Odisha, India

    Science.gov (United States)

    Jena, Santanu K.; Tayung, Kumanand; Rath, Chandi C.; Parida, Debraj

    2015-01-01

    Similipal Biosphere Reserve (SBR) is a tropical moist deciduous forest dominated by the species Shorea robusta . To the best of our knowledge their rich biodiversity has not been explored in term of its microbial wealth. In the present investigation, soil samples were collected from ten selected sites inside SBR and studied for their physicochemical parameters and culturable soil fungal diversity. The soil samples were found to be acidic in nature with a pH ranging from of 5.1–6.0. Highest percentage of organic carbon and moisture content were observed in the samples collected from the sites, Chahala-1 and Chahala-2. The plate count revealed that fungal population ranged from 3.6 × 10 4 –2.1 × 10 5 and 5.1 × 10 4 –4.7 × 10 5 cfu/gm of soil in summer and winter seasons respectively. The soil fungus, Aspergillus niger was found to be the most dominant species and Species Important Values Index (SIVI) was 43.4 and 28.6 in summer and winter seasons respectively. Among the sites studied, highest fungal diversity indices were observed during summer in the sites, Natto-2 and Natto-1. The Shannon-Wiener and Simpson indices in these two sites were found to be 3.12 and 3.022 and 0.9425 and 0.9373 respectively. However, the highest Fisher’s alpha was observed during winter in the sites Joranda, Natto-2, Chahala-1 and Natto-1 and the values were 3.780, 3.683, 3.575 and 3.418 respectively. Our investigation revealed that, fungal population was dependent on moisture and organic carbon (%) of the soil but its diversity was found to be regulated by sporulating species like Aspergillus and Penicillium . PMID:26221092

  4. Occurrence of culturable soil fungi in a tropical moist deciduous forest Similipal Biosphere Reserve, Odisha, India

    Directory of Open Access Journals (Sweden)

    Santanu K. Jena

    2015-03-01

    Full Text Available Similipal Biosphere Reserve (SBR is a tropical moist deciduous forest dominated by the species Shorea robusta. To the best of our knowledge their rich biodiversity has not been explored in term of its microbial wealth. In the present investigation, soil samples were collected from ten selected sites inside SBR and studied for their physicochemical parameters and culturable soil fungal diversity. The soil samples were found to be acidic in nature with a pH ranging from of 5.1–6.0. Highest percentage of organic carbon and moisture content were observed in the samples collected from the sites, Chahala-1 and Chahala-2. The plate count revealed that fungal population ranged from 3.6 × 104–2.1 × 105 and 5.1 × 104–4.7 × 105 cfu/gm of soil in summer and winter seasons respectively. The soil fungus, Aspergillus niger was found to be the most dominant species and Species Important Values Index (SIVI was 43.4 and 28.6 in summer and winter seasons respectively. Among the sites studied, highest fungal diversity indices were observed during summer in the sites, Natto-2 and Natto-1. The Shannon-Wiener and Simpson indices in these two sites were found to be 3.12 and 3.022 and 0.9425 and 0.9373 respectively. However, the highest Fisher’s alpha was observed during winter in the sites Joranda, Natto-2, Chahala-1 and Natto-1 and the values were 3.780, 3.683, 3.575 and 3.418 respectively. Our investigation revealed that, fungal population was dependent on moisture and organic carbon (% of the soil but its diversity was found to be regulated by sporulating species like Aspergillus and Penicillium.

  5. Dragonfly (insecta: odonata) diversity in two use of soils in a tropical dry forest

    International Nuclear Information System (INIS)

    Altamiranda S, Mariano

    2009-01-01

    Dragonfly diversity was estimated in the Agricultural Center Cotove (Santafe de Antioquia-Colombia). Active capture using an entomological net was used. Each transect was located perpendicular to the water body, for a length of approximately 200 m and a lateral extension of 8 m. Twenty Odonata species were registered, from 5 families and 15 genus. Libellulidae showed the biggest abundance and richness, with 65 specimens that represent 53.7% of the total abundance, and 12 species that represent 60% of the registered community. The diversity was high in the forest in reference at crop; however, the low abundances register highlight the need for greater sampling effort in cultivating, for a better estimate of ? diversity; the diversity was of 12 species and the complementary index was of 0.6, it indicates that the Odonata's fauna is characteristic and distinctive for each use of soil.

  6. Particle growth in an isoprene-rich forest: Influences of urban, wildfire, and biogenic air masses

    Science.gov (United States)

    Gunsch, Matthew J.; Schmidt, Stephanie A.; Gardner, Daniel J.; Bondy, Amy L.; May, Nathaniel W.; Bertman, Steven B.; Pratt, Kerri A.; Ault, Andrew P.

    2018-04-01

    Growth of freshly nucleated particles is an important source of cloud condensation nuclei (CCN) and has been studied within a variety of environments around the world. However, there remains uncertainty regarding the sources of the precursor gases leading to particle growth, particularly in isoprene-rich forests. In this study, particle growth events were observed from the 14 total events (31% of days) during summer measurements (June 24 - August 2, 2014) at the Program for Research on Oxidants PHotochemistry, Emissions, and Transport (PROPHET) tower within the forested University of Michigan Biological Station located in northern Michigan. Growth events were observed within long-range transported air masses from urban areas, air masses impacted by wildfires, as well as stagnant, forested/regional air masses. Growth events observed during urban-influenced air masses were prevalent, with presumably high oxidant levels, and began midday during periods of high solar radiation. This suggests that increased oxidation of biogenic volatile organic compounds (BVOCs) likely contributed to the highest observed particle growth in this study (8 ± 2 nm h-1). Growth events during wildfire-influenced air masses were observed primarily at night and had slower growth rates (3 ± 1 nm h-1). These events were likely influenced by increased SO2, O3, and NO2 transported within the smoke plumes, suggesting a role of NO3 oxidation in the production of semi-volatile compounds. Forested/regional air mass growth events likely occurred due to the oxidation of regionally emitted BVOCs, including isoprene, monoterpenes, and sesquiterpenes, which facilitated multiday growth events also with slower rates (3 ± 2 nm h-1). Intense sulfur, carbon, and oxygen signals in individual particles down to 20 nm, analyzed by transmission electron microscopy with energy dispersive X-ray spectroscopy (TEM-EDX), suggest that H2SO4 and secondary organic aerosol contributed to particle growth. Overall, aerosol

  7. LBA-ECO TG-07 Soil Trace Gas Flux and Root Mortality, Tapajos National Forest

    Science.gov (United States)

    R.K. Varner; M.M. Keller

    2009-01-01

    This data set reports the results of an experiment that tested the short-term effects of root mortality on the soil-atmosphere fluxes of nitrous oxide, nitric oxide, methane, and carbon dioxide in a tropical evergreen forest. Weekly trace gas fluxes are provided for treatment and control plots on sand and clay tropical forest soils in two comma separated ASCII files....

  8. Soil properties and aspen development five years after compaction and forest floor removal

    Science.gov (United States)

    Douglas M. Stone; John D. Elioff

    1998-01-01

    Forest management activities that decrease soil porosity and remove organic matter have been associated with declines in site productivity. In the northern Lake States region, research is in progress in the aspen (Populus tremuloides Michx. and P. grandidentata Michx.) forest type to determine effects of soil compaction and organic...

  9. Comparing soil organic carbon dynamics in plantation and secondary forest in wet tropics in Puerto Rico

    Science.gov (United States)

    LI YIQING; MING XU; ZOU XIAOMING; PEIJUN SHI§; YAOQI ZHANG

    2005-01-01

    We compared the soil carbon dynamics between a pine plantation and a secondary forest, both of which originated from the same farmland abandoned in 1976 with the same cropping history and soil conditions, in the wet tropics in Puerto Rico from July 1996 to June 1997. We found that the secondary forest accumulated the heavy-fraction organic carbon (HF-OC) measured by...

  10. Temporal and spatial variation of nitrogen transformations in a coniferous forest soils.

    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

  11. Soil-mediated filtering organizes tree assemblages in regenerating tropical forests

    NARCIS (Netherlands)

    Pinho, Bruno Ximenes; Melo, de Felipe Pimentel Lopes; Arroyo-Rodríguez, Víctor; Pierce, Simon; Lohbeck, Madelon; Tabarelli, Marcelo

    2018-01-01

    Secondary forests are increasingly dominant in human-modified tropical landscapes, but the drivers of forest recovery remain poorly understood. Soil conditions influence plant community composition, and are expected to change over a gradient of succession. However, the role of soil conditions as

  12. A conceptual framework: redifining forests soil's critical acid loads under a changing climate

    Science.gov (United States)

    Steven G. McNulty; Johnny L. Boggs

    2010-01-01

    Federal agencies of several nations have or are currently developing guidelines for critical forest soil acid loads. These guidelines are used to establish regulations designed to maintain atmospheric acid inputs below levels shown to damage forests and streams. Traditionally, when the critical soil acid load exceeds the amount of acid that the ecosystem can absorb, it...

  13. Methodology for estimating soil carbon for the forest carbon budget model of the United States, 2001

    Science.gov (United States)

    L. S. Heath; R. A. Birdsey; D. W. Williams

    2002-01-01

    The largest carbon (C) pool in United States forests is the soil C pool. We present methodology and soil C pool estimates used in the FORCARB model, which estimates and projects forest carbon budgets for the United States. The methodology balances knowledge, uncertainties, and ease of use. The estimates are calculated using the USDA Natural Resources Conservation...

  14. Sustained effects of atmospheric [CO2] and nitrogen availability on forest soil CO2 efflux

    Science.gov (United States)

    A. Christopher Oishi; Sari Palmroth; Kurt H. Johnsen; Heather R. McCarthy; Ram. Oren

    2014-01-01

    Soil CO2 efflux (Fsoil) is the largest source of carbon from forests and reflects primary productivity as well as how carbon is allocated within forest ecosystems. Through early stages of stand development, both elevated [CO2] and availability of soil nitrogen (N; sum of mineralization, deposition, and fixation) have been shown to increase gross primary productivity,...

  15. Visually Determined Soil Disturbance Classes Used as Indices of Forest Harvesting Disturbance

    Science.gov (United States)

    W. Michael Aust; James A. Burger; Emily A. Carter; David P. Preston; Steven C. Patterson

    1998-01-01

    Visual estimates of soil and site disturbances are used by foresters, soil scientists, logging supervisors. and machinery operators to minimize harvest disturbances to forest sites, to evaluate compliance with forestry Best Management Practices (BMPs), and to determine the need for ameliorative practices such as tnechanical site preparation. Although estimates are...

  16. Species richness and relative abundance of birds in natural and anthropogenic fragments of Brazilian Atlantic forest

    Directory of Open Access Journals (Sweden)

    Luiz dos Anjos

    2004-06-01

    Full Text Available Bird communities were studied in two types of fragmented habitat of Atlantic forest in the State of Paraná, southern Brazil; one consisted of forest fragments that were created as a result of human activities (forest remnants, the other consisted of a set of naturally occurring forest fragments (forest patches. Using quantitative data obtained by the point counts method in 3 forest patches and 3 forest remnants during one year, species richness and relative abundance were compared in those habitats, considering species groups according to their general feeding habits. Insectivores, omnivores, and frugivores presented similar general tendencies in both habitats (decrease of species number with decreasing size and increasing isolation of forest fragment. However, these tendencies were different, when considering the relative abundance data: the trunk insectivores presented the highest value in the smallest patch while the lowest relative abundance was in the smallest remnant. In the naturally fragmented landscape, time permitted that the loss of some species of trunk insectivores be compensated for the increase in abundance of other species. In contrast, the remnants essentially represented newly formed islands that are not yet at equilibrium and where future species losses would make them similar to the patches.Comunidades de aves foram estudadas em duas regiões fragmentadas de floresta Atlântica no Estado do Paraná, sul do Brasil; uma região é constituída de fragmentos florestais que foram criados como resultado de atividades humanas (remanescentes florestais e a outra de um conjunto de fragmentos florestais naturais (manchas de floresta. Usando dados quantitativos (o método de contagens pontuais previamente obtidos em 3 manchas de floresta e em 3 remanescentes florestais durante um ano, a riqueza e a abundância relativa de aves foram comparadas naqueles habitats considerando as espécies pelos seus hábitos alimentares. Inset

  17. The detection of thermophilous forest hotspots in Poland using geostatistical interpolation of plant richness

    Directory of Open Access Journals (Sweden)

    Marcin Kiedrzyński

    2014-07-01

    Full Text Available Attempts to study biodiversity hotspots on a regional scale should combine compositional and functionalist criteria. The detection of hotspots in this study uses one ecologically similar group of high conservation value species as hotspot indicators, as well as focal habitat indicators, to detect the distribution of suitable environmental conditions. The method is assessed with reference to thermophilous forests in Poland – key habitats for many rare and relict species. Twenty-six high conservation priority species were used as hotspot indicators, and ten plant taxa characteristic of the Quercetalia pubescenti-petraeae phytosociological order were used as focal habitat indicators. Species distribution data was based on a 10 × 10 km grid. The number of species per grid square was interpolated by the ordinary kriging geostatistical method. Our analysis largely determined the distribution of areas with concentration of thermophilous forest flora, but also regional disjunctions and geographical barriers. Indicator species richness can be interpreted as a reflection of the actual state of habitat conditions. It can also be used to determine the location of potential species refugia and possible past and future migration routes.

  18. Factors for Microbial Carbon Sources in Organic and Mineral Soils from Eastern United States Deciduous Forests

    Energy Technology Data Exchange (ETDEWEB)

    Stitt, Caroline R. [Mills College, Oakland, CA (United States)

    2013-09-16

    Forest soils represent a large portion of global terrestrial carbon; however, which soil carbon sources are used by soil microbes and respired as carbon dioxide (CO2) is not well known. This study will focus on characterizing microbial carbon sources from organic and mineral soils from four eastern United States deciduous forests using a unique radiocarbon (14C) tracer. Results from the dark incubation of organic and mineral soils are heavily influenced by site characteristics when incubated at optimal microbial activity temperature. Sites with considerable differences in temperature, texture, and location differ in carbon source attribution, indicating that site characteristics play a role in soil respiration.

  19. Comparison of Organic Matter Dynamics in Soil between Japanese Cedar (Cryptomeria japonica) Forest and Adjacent Japanese Red Pine (Pinus densiflora) Forest Established on Flatland

    OpenAIRE

    Terumasa, Takahashi; Akiko, Minami; Yoshito, Asano; Tatsuaki, Kobayashi; Faculty of Horticulture, Chiba Universit; Faculty of Horticulture, Chiba University:(Present)Hashikami town office; Faculty of Horticulture, Chiba University; Faculty of Horticulture, Chiba University

    1999-01-01

    In order to clarify the effects of tree species on organic matter dynamics in soil, we investigated the amount of forest floor material, leaf litter decomposition rate, soil chemical characteristics, soil respiration rate and cellulose decomposition rate in a Japanese cedar forest (cedar plot) and an adjacent Japanese red pine forest (pine plot) established on a flatland. The amount of forest floor material in the cedar plot was 34.5 Mg ha^ which was greater than that in the pine plot. Becaus...

  20. Influence of Uranium on Bacterial Communities: A Comparison of Natural Uranium-Rich Soils with Controls

    Science.gov (United States)

    Mondani, Laure; Benzerara, Karim; Carrière, Marie; Christen, Richard; Mamindy-Pajany, Yannick; Février, Laureline; Marmier, Nicolas; Achouak, Wafa; Nardoux, Pascal; Berthomieu, Catherine; Chapon, Virginie

    2011-01-01

    This study investigated the influence of uranium on the indigenous bacterial community structure in natural soils with high uranium content. Radioactive soil samples exhibiting 0.26% - 25.5% U in mass were analyzed and compared with nearby control soils containing trace uranium. EXAFS and XRD analyses of soils revealed the presence of U(VI) and uranium-phosphate mineral phases, identified as sabugalite and meta-autunite. A comparative analysis of bacterial community fingerprints using denaturing gradient gel electrophoresis (DGGE) revealed the presence of a complex population in both control and uranium-rich samples. However, bacterial communities inhabiting uraniferous soils exhibited specific fingerprints that were remarkably stable over time, in contrast to populations from nearby control samples. Representatives of Acidobacteria, Proteobacteria, and seven others phyla were detected in DGGE bands specific to uraniferous samples. In particular, sequences related to iron-reducing bacteria such as Geobacter and Geothrix were identified concomitantly with iron-oxidizing species such as Gallionella and Sideroxydans. All together, our results demonstrate that uranium exerts a permanent high pressure on soil bacterial communities and suggest the existence of a uranium redox cycle mediated by bacteria in the soil. PMID:21998695

  1. Radionuclide transport along a boreal hill slope - elevated soil water concentrations in riparian forest soils

    Energy Technology Data Exchange (ETDEWEB)

    Lidman, Fredrik; Boily, Aasa; Laudon, Hjalmar [Dept. of Forest Ecology and Management, Swedish University of Agricultural Sciences, 901 83 Umeaa (Sweden); Koehler, Stephan J. [Dept. of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, P.O. 7050, 750 07 Uppsala (Sweden)

    2014-07-01

    The transport of radionuclides from forest ecosystems and out into surface waters is a crucial process for understanding the long-term fate of radionuclides in the boreal landscape. Boreal forests are typically dominated by podzol soils, but the streams draining the forests are often lined by highly organic, often peat-like soils, which the radionuclides must pass through in order to reach the stream. This so-called riparian zone therefore represents a fundamentally different biogeochemical environment than ordinary forest soils, e.g. by exhibiting significantly lower pH and higher concentrations of organic colloids, which significantly can affect the mobility of many radionuclides. Since the riparian zone is the last terrestrial environment that the groundwater is in contact with before it enters the stream, previous research has demonstrated its profound impact on the stream water chemistry. Hence, the riparian soils should also be important for the transport and accumulation of radionuclides. Therefore, soil water was sampled using suction lysimeters installed at different depths along a 22 m long forested hill slope transect in northern Sweden, following the flow pathway of the groundwater from the uphill podzol to the riparian zone near the stream channel. The analyses included a wide range of hydrochemical parameters and many radiologically important elements, e.g. U, Th, Ni, C, Sr, Cs, REEs and Cl. The sampling was repeated ten times throughout a year in order to also capture the temporal variability of the soil water chemistry. The water chemistry of the investigated transect displayed a remarkable change as the groundwater approached the stream channel. Strongly increased concentrations of many elements were observed in the riparian soils. For instance, the concentrations of Th were more than 100 times higher than in the riparian zone than in the uphill forest, suggesting that the riparian zone may be a hotspot for radionuclide accumulation. The reason

  2. Deforestation projections for carbon-rich peat swamp forests of Central Kalimantan, Indonesia.

    Science.gov (United States)

    Fuller, Douglas O; Hardiono, Martin; Meijaard, Erik

    2011-09-01

    We evaluated three spatially explicit land use and cover change (LUCC) models to project deforestation from 2005-2020 in the carbon-rich peat swamp forests (PSF) of Central Kalimantan, Indonesia. Such models are increasingly used to evaluate the impact of deforestation on carbon fluxes between the biosphere and the atmosphere. We considered both business-as-usual (BAU) and a forest protection scenario to evaluate each model's accuracy, sensitivity, and total projected deforestation and landscape-level fragmentation patterns. The three models, Dinamica EGO (DE), GEOMOD and the Land Change Modeler (LCM), projected similar total deforestation amounts by 2020 with a mean of 1.01 million ha (Mha) and standard deviation of 0.17 Mha. The inclusion of a 0.54 Mha strict protected area in the LCM simulations reduced projected loss to 0.77 Mha over 15 years. Calibrated parameterizations of the models using nearly identical input drivers produced very different landscape properties, as measured by the number of forest patches, mean patch area, contagion, and Euclidean nearest neighbor determined using Fragstats software. The average BAU outputs of the models suggests that Central Kalimantan may lose slightly less than half (45.1%) of its 2005 PSF by 2020 if measures are not taken to reduce deforestation there. The relatively small reduction of 0.24 Mha in deforestation found in the 0.54 Mha protection scenario suggests that these models can identify potential leakage effects in which deforestation is forced to occur elsewhere in response to a policy intervention.

  3. Effects of exotic plantation forests on soil edaphon and organic matter fractions.

    Science.gov (United States)

    Xu, Gang; Liu, Yao; Long, Zhijian; Hu, Shanglian; Zhang, Yuanbin; Jiang, Hao

    2018-06-01

    There is uncertainty and limited knowledge regarding soil microbial properties and organic matter fractions of natural secondary forest accompanying chemical environmental changes of replacement by pure alien plantation forests in a hilly area of southwest of Sichuan province China. The aim of this study was to evaluate the impact of natural secondary forest (NSF) to pure Cryptomeria fortunei forest (CFF) and Cunninghamia lanceolata forest (CLF) on soil organic fractions and microbial communities. The results showed that the soil total phospholipid fatty acids (PLFAs), total bacteria and fungi, microbial carbon pool, organic recalcitrant carbon (C) and (N) fractions, soil microbial quotient and labile and recalcitrant C use efficiencies in each pure plantation were significantly decreased, but their microbial N pool, labile C and N pools, soil carbon dioxide efflux, soil respiratory quotient and recalcitrant N use efficiency were increased. An RDA analysis revealed that soil total PLFAs, total bacteria and fungi and total Gram-positive and Gram-negative bacteria were significantly associated with exchangeable Al 3+ , exchangeable acid, Al 3+ , available P and Mg 2+ and pH, which resulted into microbial functional changes of soil labile and recalcitrant substrate use efficiencies. Modified microbial C- and N-use efficiency due to forest conversion ultimately meets those of rapidly growing trees in plantation forests. Enlarged soil labile fractions and soil respiratory quotients in plantation forests would be a potential positive effect for C source in the future forest management. Altogether, pure plantation practices could provoke regulatory networks and functions of soil microbes and enzyme activities, consequently leading to differentiated utilization of soil organic matter fractions accompanying the change in environmental factors. Copyright © 2018 Elsevier B.V. All rights reserved.

  4. The effect of fire intensity on soil respiration in Siberia boreal forest

    Science.gov (United States)

    S. Baker; A. V. Bogorodskaya

    2010-01-01

    Russian boreal forests have an annual wildfire activity averaging 10 to 20 million ha, which has increased in recent years. This wildfire activity, in response to changing climate has the potential to significantly affect the carbon storage capacity of Siberian forests. A better understanding of the effect of fire on soil respiration rates in the boreal forest of...

  5. A network of experimental forests and ranges: Providing soil solutions for a changing world

    Science.gov (United States)

    Mary Beth. Adams

    2010-01-01

    The network of experimental forests and ranges of the USDA Forest Service represents significant opportunities to provide soil solutions to critical issues of a changing world. This network of 81 experimental forests and ranges encompasses broad geographic, biological, climatic and physical scales, and includes long-term data sets, and long-term experimental...

  6. Impact of biomass harvesting on forest soil productivity in the northern Rocky Mountains

    Science.gov (United States)

    Woongsoon Jang; Christopher R. Keyes; Deborah Page-Dumroese

    2015-01-01

    Biomass harvesting extracts an increased amount of organic matter from forest ecosystems over conventional harvesting. Since organic matter plays a critical role in forest productivity, concerns of potential negative long-term impacts of biomass harvesting on forest productivity (i.e., changing nutrient/water cycling, aggravating soil properties, and compaction) have...

  7. Carbon and nitrogen in forest floor and mineral soil under six common European tree species

    DEFF Research Database (Denmark)

    Vesterdal, Lars; Schmidt, Inger K.; Callesen, Ingeborg

    2007-01-01

    The knowledge of tree species effects on soil C and N pools is scarce, particularly for European deciduous tree species. We studied forest floor and mineral soil carbon and nitrogen under six common European tree species in a common garden design replicated at six sites in Denmark. Three decades...... on forest floor C and N content was primarily attributed to large differences in turnover rates as indicated by fractional annual loss of forest floor C and N. The C/N ratio of foliar litterfall was a good indicator of forest floor C and N contents, fractional annual loss of forest floor C and N...

  8. Illuminating pathways of forest nutrient provision: relative release from soil mineral and organic pools

    Science.gov (United States)

    Hauser, E.; Billings, S. A.

    2017-12-01

    Depletion of geogenic nutrients during soil weathering can prompt vegetation to rely on other sources, such as organic matter (OM) decay, to meet growth requirements. Weathered soils also tend to permit deep rooting, a phenomenon sometimes attributed to vegetation foraging for geogenic nutrients. This study examines the extent to which OM recycling provides nutrients to vegetation growing in soils with diverse weathering states. We thus address the fundamental problem of how forest vegetation obtains sufficient nutrition to support productivity despite wide variation in soils' nutrient contents. We hypothesized that vegetation growing on highly weathered soils relies on nutrients released from OM decay to a greater extent than vegetation growing on less weathered, more nutrient-rich substrates. For four mineralogically diverse Critical Zone Observatories (CZO) and Critical Zone Exploratory Network sites, we calculated weathering indices and approximated vegetation nutrient demand and nutrient release from OM decay. We also measured nutrient release rates from OM decay at each site. We then assessed the relationship between degree of soil weathering and the estimated fraction of nutrient demand satisfied by OM derived nutrients. Results are consistent with our hypothesis. The chemical index of alteration (CIA), a weathering index that increases in value with mineral depletion, varies predictably from 90 at the highly weathered Calhoun CZO to 60 at the Catalina CZO, where soils are more recently developed. Estimates of rates of K release from OM decay increase with CIA values. The highest release rate is 2.4 gK m-2 y-1 at Calhoun, accounting for 30% of annual vegetation K uptake; at Catalina, less than 0.5 gm-2 y-1 K is released, meeting 14% of vegetation demand. CIA also co-varies with rooting depth across sites: the deepest roots at the Calhoun sites are growing in soils with the highest CIA values, while the deepest roots at Catalina sites are growing in soils

  9. How Rice (Oryza sativa L.) Responds to Elevated As under Different Si-Rich Soil Amendments.

    Science.gov (United States)

    Teasley, William A; Limmer, Matthew A; Seyfferth, Angelia L

    2017-09-19

    Several strategies exist to mitigate As impacts on rice and each has its set of trade-offs with respect to yield, inorganic As content in grain, and CH 4 emissions. The addition of Si to paddy soil can decrease As uptake by rice but how rice will respond to elevated As when soil is amended with Si-rich materials is unresolved. Here, we evaluated yield impacts and grain As content and speciation in rice exposed to elevated As in response to different Si-rich soil amendments including rice husk, rice husk ash, and CaSiO 3 in a pot study. We found that As-induced yield losses were alleviated by Husk amendment, partially alleviated by Ash amendment, and not affected by CaSiO 3 amendment. Furthermore, Husk was the only tested Si-amendment to significantly decrease grain As concentrations. Husk amendment was likely effective at decreasing grain As and improving yield because it provided more plant-available Si, particularly during the reproductive and ripening phases. Both Husk and Ash provided K, which also played a role in yield improvement. This study demonstrates that while Si-rich amendments can affect rice uptake of As, the kinetics of Si dissolution and nutrient availability can also affect As uptake and toxicity in rice.

  10. The impact of clearcutting in boreal forests of Russia on soils: A review

    Science.gov (United States)

    Dymov, A. A.

    2017-07-01

    Data on the impact of tree logging in boreal forests of Russia on soils are systematized. Patterns of soil disturbances and transformation of microclimatic parameters within clearcutting areas are discussed. Changes in the conditions of pedogenesis in secondary forests are analyzed. It is suggested that the changes in forest soils upon reforestation of clearcutting areas might be considered as specific post-logging soil successions. Data characterizing changes in the thickness of litter horizons and in the intensity of elementary pedogenic processes, acidity, and the content of exchangeable bases in soils of clearcutting areas in the course of their natural reforestation are considered. The examples of human-disturbed (turbated) soil horizons and newly formed anthropogenic soils on clearcutting areas are described. It is suggested that the soils on mechanically disturbed parts of clearcutting areas can be separated as a specific group of detritus turbozems.

  11. Do agricultural terraces and forest fires recurrence in Mediterranean afforested micro-catchments alter soil quality and soil nutrient content?

    Science.gov (United States)

    E Lucas-Borja, Manuel; Calsamiglia, Aleix; Fortesa, Josep; García-Comendador, Julián; Gago, Jorge; Estrany, Joan

    2017-04-01

    Bioclimatic characteristics and intense human pressure promote Mediterranean ecosystems to be fire-prone. Afforestation processes resulting from the progressive land abandonment during the last decades led to greater biomass availability increasing the risk of large forest fires. Likewise, the abandonment and lack of maintenance in the terraced lands constitute a risk of land degradation in terms of soil quantity and quality. Despite the effects of fire and the abandonment of terraced lands on soil loss and physico-chemical properties are identified, it is not clearly understood how wildfires and abandonment of terraces affect soil quality and nutrients content. Microbiological soil parameters and soil enzymes activities are biomarkers of the soil microbial communitýs functional ability, which potentially enables them as indicators of change, disturbance or stress within the soil community. The objective of this study was to investigate the effects of terracing (abandoned and non-abandoned) on the soil enzyme activities, microbiological soil parameters and soil nutrients dynamics in three Mediterranean afforested micro-catchments (i.e., fire recurrence in the last 20 years; i.e., unburned areas, burned once and burned twice. The combination of the presence of terraces and the recurrence of forest fire, thirty-six plots of 25 m2 were sampled along the these three micro-catchments collecting four replicas at the corners of each plot. The results elucidated how non-terraced and unburned plots presented the highest values of soil respiration rate and extracellular soil enzymes. Differences between experimental plots with different forest fire recurrence or comparing terraced and unburned plots with burned plots were weaker in relation to biochemical and microbiological parameters. Soil nutrient content showed an opposite trend with higher values in terraced plots, although differences were weaker. We conclude that terraced landscapes present poorer soil quality

  12. DRAINMOD-FOREST: Integrated Modeling of Hydrology, Soil Carbon and Nitrogen Dynamics, and Plant Growth for Drained Forests.

    Science.gov (United States)

    Tian, Shiying; Youssef, Mohamed A; Skaggs, R Wayne; Amatya, Devendra M; Chescheir, G M

    2012-01-01

    We present a hybrid and stand-level forest ecosystem model, DRAINMOD-FOREST, for simulating the hydrology, carbon (C) and nitrogen (N) dynamics, and tree growth for drained forest lands under common silvicultural practices. The model was developed by linking DRAINMOD, the hydrological model, and DRAINMOD-N II, the soil C and N dynamics model, to a forest growth model, which was adapted mainly from the 3-PG model. The forest growth model estimates net primary production, C allocation, and litterfall using physiology-based methods regulated by air temperature, water deficit, stand age, and soil N conditions. The performance of the newly developed DRAINMOD-FOREST model was evaluated using a long-term (21-yr) data set collected from an artificially drained loblolly pine ( L.) plantation in eastern North Carolina, USA. Results indicated that the DRAINMOD-FOREST accurately predicted annual, monthly, and daily drainage, as indicated by Nash-Sutcliffe coefficients of 0.93, 0.87, and 0.75, respectively. The model also predicted annual net primary productivity and dynamics of leaf area index reasonably well. Predicted temporal changes in the organic matter pool on the forest floor and in forest soil were reasonable compared to published literature. Both predicted annual and monthly nitrate export were in good agreement with field measurements, as indicated by Nash-Sutcliffe coefficients above 0.89 and 0.79 for annual and monthly predictions, respectively. This application of DRAINMOD-FOREST demonstrated its capability for predicting hydrology and C and N dynamics in drained forests under limited silvicultural practices. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

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

    Directory of Open Access Journals (Sweden)

    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

  14. Vertical and horizontal distribution of radiocesium around trees in forest soil of deciduous forests, Fukushima, Japan

    Energy Technology Data Exchange (ETDEWEB)

    Takada, Mono; Oba, Yurika; Nursal, Wim I.; Yamada, Toshihiro; Okuda, Toshinori [Graduate School of Integrated Arts and Sciences, Hiroshima University, 1-7-1 Kagamiyama, Higashi- Hiroshima 739-8521 (Japan); Shizuma, Kiyoshi [Graduate School of Engineering, Hiroshima University, 1-4-1 Kagamiyama, Higashi-Hiroshima 739-8527 (Japan)

    2014-07-01

    After the 2011 Nuclear Power Plant accident in Japan, large amount of radionuclides were deposited and remains in the forest land of Fukushima region, yet still uncertain how much deposition stays in the forest. This region is mostly covered by the secondary deciduous forest which sporadically includes Japanese fir (Abies firma). As the leaves of all deciduous trees were shed, we hypothesized that the amounts of deposition radionuclides will be exhibit difference between the conifer trees (Japanese fir) and the other deciduous trees. As these trees inhabit on steep slopes, we also hypothesized there are differences in the radionuclides deposition in soils in relation to the position around tree trunk base (upper side, lower side and mid side at the foot of trees), tree species and slope angles. Study site and method: our study was conducted in deciduous forest of Fukushima region in August 2013, two and a half years after the accident. Samples of litter layer and two soil layers (0 - 5, 5 - 10 cm) were collected under Abies firma and eight deciduous tree species. In total 23 trees in eight forest stands were investigated. Under one tree, samples were taken from four pints (upper side, lower side and mid sides at the foot of trees) around a tree trunk within a radius of one meter from the base of tree trunks. Angle of slope at each tree was also checked. The samples were dried (70 deg. C, 48 hr) and radiocesium and potassium-40 was determined by a germanium detector (GEM Series HPGe Coaxial Detector System) (measurement time 300 - 30000 sec). Results and discussion: we found that radiocesium contained in litter layer accounts for more than 80% of total amount (within litter layer to 10 cm depth from the surface), and almost all the radiocesium exists within litter layer up to 5 cm depth. Although it is well known that cesium shows similar movement to potassium in a plant body, soil contained much more amount of potassium-40 than litter layer. We predicted that

  15. Long-term effects of fragmentation and fragment properties on bird species richness in Hawaiian forests

    Science.gov (United States)

    David J. Flaspohler; Christian P. Giardina; Gregory P. Asner; Patrick Hart; Jonathan Price; Cassie Ka’apu Lyons; Xeronimo. Castaneda

    2010-01-01

    Forest fragmentation is a common disturbance affecting biological diversity, yet the impacts of fragmentation on many forest processes remain poorly understood. Forest restoration is likely to be more successful when it proceeds with an understanding of how native and exotic vertebrates utilize forest patches of different size. We used a system of forest fragments...

  16. Biogeography and organic matter removal shape long-term effects of timber harvesting on forest soil microbial communities

    Science.gov (United States)

    Roland C Wilhelm; Erick Cardenas; Kendra R Maas; Hilary Leung; Larisa McNeil; Shannon Berch; William Chapman; Graeme Hope; J M Kranabetter; Stephane Dubé; Matt Busse; Robert Fleming; Paul Hazlett; Kara L Webster; David Morris; D Andrew Scott; William W Mohn

    2017-01-01

    The growing demand for renewable, carbon-neutral materials and energy is leading to intensified forest land-use. The long-term ecological challenges associated with maintaining soil fertility in managed forests are not yet known, in part due to the complexity of soil microbial communities and the heterogeneity of forest soils. This study determined the long-term...

  17. Production and reduction of nitrous oxide in agricultural and forest soils.

    Science.gov (United States)

    Yu, K; Chen, G; Struwe, S; Kjøller, A

    2000-06-01

    A soil-water slurry experiment was conducted to study the potentials of N2O production and reduction in denitrification of agricultural and beech forest soils in Denmark. The effects of nitrate and ammonium additions on denitrification were also investigated. The forest soil showed a higher denitrification potential than the agricultural soil. However, N2O reduction potential of the agricultural soil was higher than the beech forest soil, shown by the ratio of N2O/N2 approximately 0.11 and 3.65 in the agricultural and the beech forest soils, respectively. Both nitrate and ammonium additions stimulated the N2O production in the two soils, but reduced the N2O reduction rates in the agricultural soil slurries. In contrast to the effect on the agricultural soil, nitrate reduced the N2O reduction rate in the beech forest soil, while ammonium showed a stimulating effect on the N2O reduction activity. After one week incubation, all of the N2O produced was reduced to N2 in the agricultural soil when nitrate was still present. Nitrous oxide reduction in the beech forest soil occurred only when nitrate almost disappeared. The different nitrate inhibitory effect on the N2O reduction activity in the two soils was due to the difference in soil pH. Inhibition of nitrate on N2O reduction was significant under acidic condition. Consequently, soil could serve as a sink of atmospheric N2O under the conditions of anaerobic, pH near neutral and low nitrate content.

  18. [The concentration and distribution of 137Cs in soils of forest and agricultural ecosystems of Tula Region].

    Science.gov (United States)

    Lipatov, D N; Shcheglov, A I; Tsvetnova, O B

    2007-01-01

    The paper deals with a comparative study of 137Cs contamination in forest, old arable and cultivated soils of Tula Region. Initial interception of Chernobyl derived 137Cs is higher in forest ecosystems: oak-forest > birch-forest > pine-forest > agricultural ecosystems. Vertical migration of 137Cs in deeper layers of soils was intensive in agricultural ecosystems: cultivated soils > old arable soils > birch-forest soils > oak-forest soils > pine-forest soils. In study have been evaluated spatial variability of 137Cs in soil and asymmetrical distribution, that is a skew to the right. Spatial heterogeneity of 137Cs in agricultural soils is much lower than in forest soils. For cultivated soil are determined the rate of resuspension, which equal to 6.1 x 10(-4) day(-1). For forest soils are described the 137Cs concentration in litter of different ecosystems. The role of main accumulation and barrier of 137Cs retain higher layers of soils (horizon A1(A1E) in forest, horizon Ap in agricultural ecosystems) in long-term forecast after Chernobyl accident.

  19. Soil Organic Carbon assessment on two different forest management

    Science.gov (United States)

    Fernández Minguillón, Alex; Sauras Yera, Teresa; Vallejo Calzada, Ramón

    2017-04-01

    Soil Organic Carbon assessment on two different forest management. A.F. Minguillón1, T. Sauras1, V.R: Vallejo1. 1 Departamento de Biología Evolutiva, Ecología y Ciencias Ambientales, Universidad de Barcelona, Avenida Diagonal 643, 03080 Barcelona, Spain. Soils from arid and semiarid zones are characterized by a low organic matter content from scarce plant biomass and it has been proposed that these soils have a big capacity to carbon sequestration. According to IPCC ARS WG2 (2014) report and WG3 draft, increase carbon storage in terrestrial ecosystems has been identified such a potential tool for mitigation and adaptation to climate change. In ecological restoration context improve carbon sequestration is considered a management option with multiple benefits (win-win-win). Our work aims to analyze how the recently developed restoration techniques contributed to increases in terrestial ecosystem carbon storage. Two restoration techniques carried out in the last years have been evaluated. The study was carried out in 6 localities in Valencian Community (E Spain) and organic horizons of two different restoration techniques were evaluated; slash brush and thinning Aleppo pine stands. For each technique, carbon stock and its physical and chemical stability has been analysed. Preliminary results point out restoration zones acts as carbon sink due to (1) the relevant necromass input produced by slash brush increases C stock on the topsoil ;(2) Thinning increase carbon accumulation in vegetation.

  20. Seasonal dynamics of soil CO2 emission in the boreal forests in Central Siberia

    Science.gov (United States)

    Makhnykina, A. V.; Prokishkin, A. S.; Zyryanov, V.; Verkhovets, S. V.

    2016-12-01

    A large amount of carbon in soil is released to the atmosphere through soil respiration, which is the main pathway of transferring carbon from terrestrial ecosystems (Comstedt et al., 2011). Considering that boreal forests is a large terrestrial sink (Tans et al., 1990) and represent approximately 11 % of the Earth's total land area (Gower et al., 2001), even a small change in soil respiration could significantly intensify - or mitigate - current atmospheric increases of CO2, with potential feedbacks to climate change. The objectives of the present study are: (a) to study the dynamic of CO2emission from the soil surface during summer season (from May to October); (b) to identify the reaction of soil respiration to different amount of precipitation as the main limiting factor in the region. The research was carried out in the pine forests in Central Siberia (60°N, 90°E), Russia. Sample plots were represented by the lichen pine forest, moss pine forest, mixed forest and anthropogenic destroyed area. We used the automated soil CO2 flux system based on the infrared gas analyzer LI-8100 for measuring the soil efflux. Soil temperature was measured with Soil Temperature Probe Type E in three depths 5, 10, 15 cm. Volumetric soil moisture was measured with Theta Probe Model ML2. The presence and type of ground cover substantially affects the value of soil respiration fluxes. The carbon dioxide emission from the soil surface averaged was 5.4 ±2.3 μmol CO2 m-2 s-1. The destroyed area without plant cover demonstrated the lowest soil respiration (0.1-5.6 μmol CO2 m-2 s-1). The lowest soil respiration among forested areas was observed in the feathermoss pine forest. The lichen pine forest soil respiration was characterized by averages values. The maximum soil respiration values and seasonal fluctuations were obtained in the mixed forest (2.3-29.3 μmol CO2 m-2 s-1). The analysis of relation between soil CO2 efflux and amount of precipitation showed that the site without any

  1. Differential responses of soil bacteria, fungi, archaea and protists to plant species richness and plant functional group identity.

    Science.gov (United States)

    Dassen, Sigrid; Cortois, Roeland; Martens, Henk; de Hollander, Mattias; Kowalchuk, George A; van der Putten, Wim H; De Deyn, Gerlinde B

    2017-08-01

    Plants are known to influence belowground microbial community structure along their roots, but the impacts of plant species richness and plant functional group (FG) identity on microbial communities in the bulk soil are still not well understood. Here, we used 454-pyrosequencing to analyse the soil microbial community composition in a long-term biodiversity experiment at Jena, Germany. We examined responses of bacteria, fungi, archaea, and protists to plant species richness (communities varying from 1 to 60 sown species) and plant FG identity (grasses, legumes, small herbs, tall herbs) in bulk soil. We hypothesized that plant species richness and FG identity would alter microbial community composition and have a positive impact on microbial species richness. Plant species richness had a marginal positive effect on the richness of fungi, but we observed no such effect on bacteria, archaea and protists. Plant species richness also did not have a large impact on microbial community composition. Rather, abiotic soil properties partially explained the community composition of bacteria, fungi, arbuscular mycorrhizal fungi (AMF), archaea and protists. Plant FG richness did not impact microbial community composition; however, plant FG identity was more effective. Bacterial richness was highest in legume plots and lowest in small herb plots, and AMF and archaeal community composition in legume plant communities was distinct from that in communities composed of other plant FGs. We conclude that soil microbial community composition in bulk soil is influenced more by changes in plant FG composition and abiotic soil properties, than by changes in plant species richness per se. © 2017 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  2. ARSENIC ADSORPTION AND REDUCTION IN IRON-RICH SOILS NEARBY LANDFILLS IN NORTHWEST FLORIDA

    Directory of Open Access Journals (Sweden)

    Hongqin Xue

    2016-01-01

    Full Text Available In Florida, soils are mainly composed of Myakka, an acid soil characterized by a subsurface accumulation of humus and Al(III and Fe(III oxides. Downgradient of the landfills in Northwest Florida, elevated levels of iron and arsenic observations had been made in the groundwater from monitoring wells, which was attributed to the geomicrobial iron and arsenic reduction. There is thus an immediate research need for a better understanding of the reduction reactions that are responsible for the mobilization of iron and arsenic in the subsurface soil nearby landfills. Owing to the high Fe(III oxide content, As(V adsorption reactions with Fe(III oxide surfaces are particularly important, which may control As(V reduction. This research focused on the investigation of the biogeochemical processes of the subsurface soil nearby landfills of Northwest Florida. Arsenic and iron reduction was studied in batch reactors and quantified based on Monod-type microbial kinetic growth simulations. As(V adsorption in iron-rich Northwest Floridian soils was further investigated to explain the reduction observations. It was demonstrated in this research that solubilization of arsenic in the subsurface soil nearby landfills in Northwest Florida would likely occur under conditions favoring Fe(III dissimilatory reduction.

  3. Feedback of global warming to soil carbon cycling in forest ecosystems

    International Nuclear Information System (INIS)

    Nakane, Kaneyuki

    1993-01-01

    Thus in this study the simulation of soil carbon cycling and dynamics of its storage in several types of mature forests developed from the cool-temperate to the tropics was carried out for quantitatively assessing carbon loss from the soil under several scenarios of global warming, based on the model of soil carbon cycling in forest ecosystems (Nakane et al. 1984, 1987 and Nakane 1992). (J.P.N.)

  4. Landscape Influences on Potential Soil Respiration Rates in a Forested Watershed of Southeastern Kentucky

    Science.gov (United States)

    Amanda C. Abnee; James A. Thompson; Randall K. Kolka; Elisa M. D' Angelo; Mark S. Coyne

    2004-01-01

    Soil respiration measurements conducted in the laboratory have been shown to be related to temperature and moisture, with maximum rates at soil temperatures between 25 and 40°C and soil moisture between -0.01 and -0.10 MPa. A preliminary study using forest soils from eastern Kentucky supported the previous research with soil respiration rates greater at 25°C than at 15...

  5. Preliminary study of prairies forested with Eucalyptus sp. at the northwestern Uruguayan soils

    International Nuclear Information System (INIS)

    Carrasco-Letelier, L.; Eguren, G.; Castineira, C.; Parra, O.; Panario, D.

    2004-01-01

    The forestation of Uruguayan natural prairie soil does not always ensure an increase of soil carbon sink. - The land cover change of Uruguayan Forestal Plan provoked biogeochemical changes on horizon Au 1 of Argiudols; in native prairies which were replaced by monoculture Eucalyptus sp. plantation with 20 year rotations as trees. Five fields forested and six natural prairies were compared. The results not only show a statistical significant soil acidification, diminution of soil organic carbon, increase of aliphaticity degree of humic substances, and increase of affinity and capacity of hydrolytic activity from soil microbial communities for forested sites with Eucalyptus sp. but also, a tendency of podzolization and/or mineralization by this kind of land cover changes, with a net soil organic lost of 16.6 tons ha -1 in the horizon Au 1 of soil under Eucalyptus sp. plantation compared with prairie. Besides, these results point out the necessity of correction of the methodology used by assigned Uruguayan commission to assess the national net emission of greenhouse gases, since the mineralization and/or podzolization process detected in forested soil imply a overestimation of soil organic carbon. The biochemical parameters show a statistical significant correlation between the soil organic carbon status and these parameters which were presented as essential for the correct evaluation of Uruguayan soil carbon sink

  6. Climate response of the soil nitrogen cycle in three forest types of a headwater Mediterranean catchment

    Science.gov (United States)

    Lupon, Anna; Gerber, Stefan; Sabater, Francesc; Bernal, Susana

    2015-05-01

    Future changes in climate may affect soil nitrogen (N) transformations, and consequently, plant nutrition and N losses from terrestrial to stream ecosystems. We investigated the response of soil N cycling to changes in soil moisture, soil temperature, and precipitation across three Mediterranean forest types (evergreen oak, beech, and riparian) by fusing a simple process-based model (which included climate modifiers for key soil N processes) with measurements of soil organic N content, mineralization, nitrification, and concentration of ammonium and nitrate. The model describes sources (atmospheric deposition and net N mineralization) and sinks (plant uptake and hydrological losses) of inorganic N from and to the 0-10 cm soil pool as well as net nitrification. For the three forest types, the model successfully recreated the magnitude and temporal pattern of soil N processes and N concentrations (Nash-Sutcliffe coefficient = 0.49-0.96). Changes in soil water availability drove net N mineralization and net nitrification at the oak and beech forests, while temperature and precipitation were the strongest climatic factors for riparian soil N processes. In most cases, net N mineralization and net nitrification showed a different sensitivity to climatic drivers (temperature, soil moisture, and precipitation). Our model suggests that future climate change may have a minimal effect on the soil N cycle of these forests (warming and negative drying effects on the soil N cycle may counterbalance each other.

  7. Increasing soil temperature in a northern hardwood forest: effects on elemental dynamics and primary productivity

    Science.gov (United States)

    Patrick J. McHale; Myron J. Mitchell; Dudley J. Raynal; Francis P. Bowles

    1996-01-01

    To investigate the effects of elevated soil temperatures on a forest ecosystem, heating cables were buried at a depth of 5 cm within the forest floor of a northern hardwood forest at the Huntington Wildlife Forest (Adirondack Mountains, New York). Temperature was elevated 2.5, 5.0 and 7.5?C above ambient, during May - September in both 1993 and 1994. Various aspects of...

  8. Persistent Soil Seed Banks for Natural Rehabilitation of Dry Tropical Forests in Northern Ethiopia

    OpenAIRE

    Gebrehiwot, K.; Heyn, M.; Reubens, B.; Hermy, M.; Muys, B.

    2007-01-01

    Dry tropical forests are threatened world-wide by conversion to grazing land, secondary forest, savannah or arable land. In Ethiopia, natural dry forest cover has been decreasing at an alarming rate over the last decennia and has reached a critical level. Efforts like the rehabilitation of dry forests to curb this ecological degradation, need a stronger scientific basis than currently available. The aim of the present research was to test the hypothesis whether soil seed banks can contribute ...

  9. Natural radionuclides in soils of a forest fragment of Atlantic Forest under ecological restoration process

    International Nuclear Information System (INIS)

    Ferreira, F.S.; Lira, M.B.; Souza, E.M.; França, E.J.

    2017-01-01

    The natural radioactive isotopes come from the radioactive series of the 238 U (Uranium Series), the 235 U (Actinium Series) and the 232 Th (Thorium Series) series, or they can occur in isolation as is the case with the 40 K. Primordial radionuclides such as 40 K, 232 Th, 235 U and 238 U exist since the formation of the earth, being found in appreciable amounts in nature and in some cases may present a mass activity above the acceptable of environmental radiation. The objective of this work was to evaluate the mass activity of 40 K, 226 Ra and 228 Ra in the soils of a fragment of Atlantic Forest under ecological restoration process located in the Municipality of Paulista, PE, Brazil. Soil samples (0 - 15 cm) were collected under the projection of the treetops of the most abundant trees in the region. After drying and comminution, analytical portions of 40 g were transferred to polyethylene petri dishes, sealed and stored for 30 days to ensure secular equilibrium. Radioactivity was quantified by High Resolution Gamma Spectrometry - EGAR. The mean physical activities of 40 K, 226 Ra and 228 Ra were 12, 15 and 20 Bq kg -1 , respectively, for the surface soil of the Parque Natural Municipal Mata do Frio. The values found were lower than those found in mangroves in the state of Pernambuco and those considered normal for soils worldwide

  10. [Early responses of soil fauna in three typical forests of south subtropical China to simulated N deposition addition].

    Science.gov (United States)

    Xu, Guolian; Mo, Jiangming; Zhou, Guoyi

    2005-07-01

    In this paper, simulated N deposition addition (0, 50, 100 and 150 kg x hm(-2) x yr(-1)) by spreading water or NH4NO3 was conducted to study the early responses of soil fauna in three typical native forests (monsoon evergreen broadleaf forest, pine forest, and broadleaf-pine mixed forest) of subtropical China. The results showed that in monsoon evergreen broadleaf forest, N deposition addition had an obviously negative effect on the three indexes for soil fauna, but in pine forest, the positive effect was significant (P soil fauna community could reach the level in mixed forest, even that in monsoon evergreen broadleaf forest at sometime. The responses in mixed forest were not obvious. In monsoon evergreen broadleaf forest, the negative effects were significant (P soil fauna groups. The results obtained might imply the N saturation-response mechanisms of forest ecosystems in subtropical China, and the conclusions from this study were also consisted with some related researches.

  11. Soil and saproxylic species (Coleoptera, Collembola, Araneae in primeval forests from the Northern part of South-Easthern Carpathians

    Directory of Open Access Journals (Sweden)

    Eugen Nițu

    2009-12-01

    Full Text Available In 2006-2007 we carried out faunal investigations in the vernal, estival and autumnal seasons in the scientific reserve "Codrul Secular Giumalău" using quantitative sampling methods. We identified 189 species of Coleoptera, 70 of Collembola and 20 of Araneae. Of these, 11 phytophagous, 18 myceto/xylo-mycetophagous, 9 mixophagous, 18 xylo- and cambio-xylemophagous, 38 saproxylophagous, 125 (55 Coleoptera, 70 Collembola detritivorous (sapro-, copro- and necrophagous, 60 (40 Coleoptera, 20 Aranea predators/parasitoids. Hymenaphorura polonica Pomorski, 1990 (Collembola, and Leiodes rhaeticus Erichson, 1845 (Coleoptera, Leiodidae, are recorded for the first time in the Romanian fauna. The rare species and characteristic species for the old primeval spruce forests are analysed for each studied taxonomic group. The species richness and faunal diversity from the Giumalău primeval spruce forest are compared with those of other very well preserved forests from the Carpathians scientific reserves (Codrul Secular Slătioara, Pietrosul Rodnei. The species abundances were used to compute the similarity indexes between the sampled sectors of forest and to perform Cluster Analysis. We observed that the dead wood in the 2nd-6th phases of decomposition has a great influence not only on the saproxylic species but also on the soil fauna like ground beetles (Carabidae that use the logs as ecologic microrefuges (winter refugees or diurnal refugees. The structure of the soil fauna is influenced by wood extraction from the forest ecosystem or by natural perturbations, this consisting in the appearance of opportunistic species as Orchesella pontica (Collembola and in decreasing of species richness of Carabidae (Coleoptera.

  12. Soil and saproxylic species (Coleoptera, Collembola, Araneae in primeval forests from the northern part of South-Easthern Carpathians

    Directory of Open Access Journals (Sweden)

    Eugen Nitu

    2009-11-01

    Full Text Available In 2006-2007 we carried out faunal investigations in the vernal, estival and autumnal seasons in the scientific reserve "Codrul Secular Giumalãu" using quantitative sampling methods. We identified 189 species of Coleoptera, 70 of Collembola and 20 of Araneae. Of these, 11 phytophagous, 18 myceto/xylo-mycetophagous,9 mixophagous, 18 xylo- and cambio-xylemophagous, 38 saproxylophagous,125 (55 Coleoptera, 70 Collembola detritivorous (sapro-, copro- andnecrophagous, 60 (40 Coleoptera, 20 Aranea predators/parasitoids. Hymenaphorura polonica Pomorski, 1990 (Collembola, and Leiodes rhaeticus Erichson, 1845 (Coleoptera, Leiodidae, are recorded for the first time in the Romanian fauna. The rare species and characteristic species for the old primeval spruce forests are analysed for each studied taxonomic group. The species richness and faunal diversity from the Giumalãu primeval spruce forest are compared with those of other very well preserved forests from the Carpathians scientific reserves (Codrul Secular Slãtioara,Pietrosul Rodnei. The species abundances were used to compute the similarity indexes between the sampled sectors of forest and to perform Cluster Analysis. We observed that the dead wood in the 2nd-6th phases of decomposition has a great influence not only on the saproxylic species but also on the soil fauna like ground beetles(Carabidae that use the logs as ecologic microrefuges (winter refugees or diurnal refugees. The structure of the soil fauna is influenced by wood extraction from the forest ecosystem or by natural perturbations, this consisting in the appearance of opportunistic species as Orchesella pontica (Collembola and in decreasing ofspecies richness of Carabidae (Coleoptera.

  13. Chemical composition of the humus layer, mineral soil and soil solution of 150 forest stands in the Netherlands in 1990

    NARCIS (Netherlands)

    Vries, de W.; Leeters, E.E.J.M.

    2001-01-01

    A nationwide assessment of the chemical composition of the humus layer, mineral topsoil (0-30 cm) and soil solution in both topsoil and subsoil (60-100 cm) was made for 150 forest stands in the year 1990. The stands, which were part of the national forest inventory on vitality, included seven tree

  14. Effect of tree species on carbon stocks in forest floor and mineral soil and implications for soil carbon inventories

    NARCIS (Netherlands)

    Schulp, C.J.E.; Nabuurs, G.J.; Verburg, P.H.; Waal, de R.W.

    2008-01-01

    Forest soil organic carbon (SOC) and forest floor carbon (FFC) stocks are highly variable. The sampling effort required to assess SOC and FFC stocks is therefore large, resulting in limited sampling and poor estimates of the size, spatial distribution, and changes in SOC and FFC stocks in many

  15. Effects of forest road amelioration techniques on soil bulk density, surface runoff, sediment transport, soil moisture and seedling growth

    Science.gov (United States)

    Randy K. Kolka; Mathew F. Smidt

    2004-01-01

    Although numerous methods have been used to retire roads, new technologies have evolved that can potentially ameliorate soil damage, lessen ,the generation of nonpoint source pollution and increase tree productivity on forest roads. In this study we investigated the effects of three forest road amelioration techniques, subsoiling, recontouring and traditional...

  16. Soils

    Science.gov (United States)

    Emily Moghaddas; Ken Hubbert

    2014-01-01

    When managing for resilient forests, each soil’s inherent capacity to resist and recover from changes in soil function should be evaluated relative to the anticipated extent and duration of soil disturbance. Application of several key principles will help ensure healthy, resilient soils: (1) minimize physical disturbance using guidelines tailored to specific soil types...

  17. Levels and patterns of polycyclic aromatic hydrocarbons (PAHs) in soils after forest fires in South Korea.

    Science.gov (United States)

    Kim, Eun Jung; Choi, Sung-Deuk; Chang, Yoon-Seok

    2011-11-01

    To investigate the influence of biomass burning on the levels of polycyclic aromatic hydrocarbons (PAHs) in soils, temporal trends and profiles of 16 US Environmental Protection Agency priority PAHs were studied in soil and ash samples collected 1, 5, and 9 months after forest fires in South Korea. The levels of PAHs in the burnt soils 1 month after the forest fires (mean, 1,200 ng/g dry weight) were comparable with those of contaminated urban soils. However, 5 and 9 months after the forest fires, these levels decreased considerably to those of general forest soils (206 and 302 ng/g, respectively). The burnt soils and ash were characterized by higher levels of light PAHs with two to four rings, reflecting direct emissions from biomass burning. Five and 9 months after the forest fires, the presence of naphthalene decreased considerably, which indicates that light PAHs were rapidly volatilized or degraded from the burnt soils. The temporal trend and pattern of PAHs clearly suggests that soils in the forest-fire region can be contaminated by PAHs directly emitted from biomass burning. However, the fire-affected soils can return to the pre-fire conditions over time through the washout and wind dissipation of the ash with high content of PAHs as well as vaporization or degradation of light PAHs.

  18. Study on the effect of organic fertilizers on soil organic matter and enzyme activities of soil in forest nursery

    Directory of Open Access Journals (Sweden)

    Piaszczyk Wojciech

    2017-09-01

    Full Text Available The aim of the study was to assess the effects of organic fertilization on selected chemical properties of the soil and the activity of dehydrogenase and β-glucosidase in the soil of forest nursery. The main goal was to evaluate the role of organic fertilizers in carbon storage in the forest nursery soil. Sample plots were located in northern Poland in the Polanów Forest District on a forest nursery. Soil samples were collected from horizon 0–20 cm for laboratory analyzes. In soil samples pH, soil texture, and organic carbon, nitrogen, base cation contents, dehydrogenase activity and β-glucosidase activity were determined. The obtained results were used to evaluate the carbon storage. The results confirm the beneficial effect of the applied organic fertilizer on chemical properties of the soils under study and their biological activity. The applied organic fertilizers had an impact on increased accumulation of soil organic matter. In the soils investigated, there was an increase in the activity of such enzymes as dehydrogenases and β-glucosidase.

  19. The ash in forest fire affected soils control the soil losses. Part 2. Current and future research challenges

    Science.gov (United States)

    Pereira, Paulo; Cerdà, Artemi

    2013-04-01

    Ash distribution on soil surface and impacts on soil properties received a great attention in recently (Pereira et al., 2010; Pereira et al., 2013). Ash it is a highly mobile material that can be easily transported wind, especially in severe wildland fires, where organic matter is reduced to dust, due the high temperatures of combustion. In the immediate period after the fire, ash cover rules soil erosion as previous researchers observed (Cerdà, 1998a; 1998b) and have strong influence on soil hydrological properties, such as water retention (Stoof et al. 2011 ) and wettability (Bodi et al., 2011). Ash it is also a valuable source of nutrients important for plant recuperation (Pereira et al., 2011; Pereira et al., 2012), but can act also as a source contamination, since are also rich in heavy metals (Pereira and Ubeda, 2010). Ash has different physical and chemical properties according the temperature of combustion, burned specie and time of exposition (Pereira et al., 2010). Thus this different properties will have different implications on soil properties including erosion that can increase due soil sealing (Onda et al. 2008) or decrease as consequence of raindrop impact reduction (Cerdà and Doerr, 2008). The current knowledge shows that ash has different impacts on soil properties and this depends not only from the type of ash produced, but of the soil properties (Woods and Balfour, 2010). After fire wind and water strong redistribute ash on soil surface, increasing the vulnerability of soil erosion in some areas, and reducing in others. Understand this mobility is fundamental have a better comprehension about the spatial and temporal effects of ash in soil erosion. Have a better knowledge about this mobility is a priority to future research. Other important aspects to have to be assessed in the future are how ash particulates percolate on soil and how ash chemical composition is important to induce soil aggregation and dispersion. How soil micro topography

  20. Spatial Structure of Soil Macrofauna Diversity and Tree Canopy in Riparian Forest of Maroon River

    Directory of Open Access Journals (Sweden)

    Ehsan Sayad

    2017-02-01

    Full Text Available Introduction: Sustainability and maintenance of riparian vegetation or restoring of degraded sites is critical to sustain inherent ecosystem function and values. Description of patterns in species assemblages and diversity is an essential step before generating hypotheses in functional ecology. If we want to have information about ecosystem function, soil biodiversity is best considered by focusing on the groups of soil organisms that play major roles in ecosystem functioning when exploring links with provision of ecosystem services. Information about the spatial pattern of soil biodiversity at the regional scale is limited though required, e.g. for understanding regional scale effects of biodiversity on ecosystem processes. The practical consequences of these findings are useful for sustainable management of soils and in monitoring soil quality. Soil macrofauna play significant, but largely ignored roles in the delivery of ecosystem services by soils at plot and landscape scales. One main reason responsible for the absence of information about biodiversity at regional scale is the lack of adequate methods for sampling and analyzing data at this dimension. An adequate approach for the analysis of spatial patterns is a transect study in which samples are taken in a certain order and with a certain distance between samples. Geostatistics provide descriptive tools such as variogram to characterize the spatial pattern of continuous and categorical soil attributes. This method allows assessment of consistency of spatial patterns as well as the scale at which they are expressed. This study was conducted to analyze spatial patterns of soil macrofauna in relation to tree canopy in the riparian forest landscape of Maroon. Materilas and Methods: The study was carried out in the Maroon riparian forest of the southeasternIran (30o 38/- 30 o 39/ N and 50 o 9/- 50 o 10/ E. The climate of the study area is semi-arid. Average yearly rainfall is about 350.04 mm

  1. Coupling of microbial nitrogen transformations and climate in sclerophyll forest soils from the Mediterranean Region of central Chile.

    Science.gov (United States)

    Pérez, Cecilia A; Armesto, Juan J

    2018-06-01

    The Mediterranean region of central Chile is experiencing extensive "mega-droughts" with detrimental effects for the environment and economy of the region. In the northern hemisphere, nitrogen (N) limitation of Mediterranean ecosystems has been explained by the decoupling between N inputs and plant uptake during the dormant season. In central Chile, soils have often been considered N-rich in comparison to other Mediterranean ecosystems of the world, yet the impacts of expected intensification of seasonal drought remain unknown. In this work, we seek to disentangle patterns of microbial N transformations and their seasonal coupling with climate in the Chilean sclerophyll forest-type. We aim to assess how water limitation affects microbial N transformations, thus addressing the impact of ongoing regional climate trends on soil N status. We studied four stands of the sclerophyll forest-type in Chile. Field measurements in surface soils showed a 67% decline of free-living diazotrophic activity (DA) and 59% decrease of net N mineralization rates during the summer rainless and dormant season, accompanied by a stimulation of in-situ denitrification rates to values 70% higher than in wetter winter. Higher rates of both free-living DA and net N mineralization found during spring, provided evidence for strong coupling of these two processes during the growing season. Overall, the experimental addition of water in the field to litter samples almost doubled DA but had no effect on denitrification rates. We conclude that coupling of microbial mediated soil N transformations during the wetter growing season explains the N enrichment of sclerophyll forest soils. Expected increases in the length and intensity of the dry period, according to climate change models, reflected in the current mega-droughts may drastically reduce biological N fixation and net N mineralization, increasing at the same time denitrification rates, thereby potentially reducing long-term soil N capital

  2. Soils of Mountainous Forests and Their Transformation under the Impact of Fires in Baikal Region

    Science.gov (United States)

    Krasnoshchekov, Yu. N.

    2018-04-01

    Data on postpyrogenic dynamics of soils under mountainous taiga cedar ( Pinus sibirica) and pine ( Pinus sylvestris) forests and subtaiga-forest-steppe pine ( Pinus sylvestris) forests in the Baikal region are analyzed. Ground litter-humus fires predominating in this region transform the upper diagnostic organic soil horizons and lead to the formation of new pyrogenic organic horizons (Opir). Adverse effects of ground fires on the stock, fractional composition, and water-physical properties of forest litters are shown. Some quantitative parameters of the liquid and solid surface runoff in burnt areas related to the slope gradient, fire intensity, and the time passed after the fire are presented. Pyrogenic destruction of forest ecosystems inevitably induces the degradation of mountainous soils, whose restoration after fires takes tens of years. The products of soil erosion from the burnt out areas complicate the current situation with the pollution of coastal waters of Lake Baikal.

  3. Tree species is the major factor explaining C:N ratios in European forest soils

    DEFF Research Database (Denmark)

    Cools, Nathalie; Vesterdal, Lars; De Vos, Bruno

    2014-01-01

    The C:N ratio is considered as an indicator of nitrate leaching in response to high atmospheric nitrogen (N) deposition. However, the C:N ratio is influenced by a multitude of other site-related factors. This study aimed to unravel the factors determining C:N ratios of forest floor, mineral soil...... mineral soil layers it was the humus type. Deposition and climatic variables were of minor importance at the European scale. Further analysis for eight main forest tree species individually, showed that the influence of environmental variables on C:N ratios was tree species dependent. For Aleppo pine...... and peat top soils in more than 4000 plots of the ICP Forests large-scale monitoring network. The first objective was to quantify forest floor, mineral and peat soil C:N ratios across European forests. Secondly we determined the main factors explaining this C:N ratio using a boosted regression tree...

  4. Richness, diversity, and similarity of arthropod prey consumed by a community of Hawaiian forest birds.

    Science.gov (United States)

    Banko, Paul C.; Peck, Robert W.; Brinck, Kevin W.; Leonard, David L.

    2015-01-01

    We evaluated the diet richness, diversity, and similarity of a community of seven endemic and two introduced passerine birds by analyzing the composition of arthropod prey in fecal samples collected during 1994–1998 at Hakalau Forest National Wildlife Refuge, Hawai‘i Island. Most prey fragments were identified to order, but we also distinguished among morpho-species of Lepidoptera based on the shape of larval (caterpillar) mandibles for higher resolution of this important prey type. Diets were compared among feeding specialists, generalists, and “intermediate” species and among introduced and three endangered Hawaiian honeycreeper (Fringillidae) species. Lepidoptera (moths), especially the larval (caterpillar) stage, comprised the greatest proportion of prey in samples of all bird species except for the introduced Japanese white-eye (Zosterops japonicus; JAWE). Araneae (spiders) was the most abundant order in JAWE samples and the second most abundant order for most other species. The two specialist honeycreepers ranked lowest in the richness and diversity of arthropod orders, but only the ‘akiapōlā‘au (Hemignathus munroi, AKIP) was significantly lower than the three generalist or intermediate honeycreeper species. The diversity of arthropod orders was significantly lower for the three endangered honeycreeper species compared to the two introduced species. No significant differences were observed among the five honeycreepers with respect to the arthropod orders they consumed. The use of arthropod orders taken by endangered honeycreepers and introduced species was significantly different in all paired comparisons except for JAWE and ‘ākepa (Loxops coccineus; AKEP). In terms of richness and diversity of caterpillar morpho-species in the diet, only the specialist, AKEP, was significantly lower than all three generalist and intermediate species. Both AKEP and AKIP consumed a significantly different diet of caterpillar morpho-species compared to at least

  5. Spatial and seasonal dynamics of surface soil carbon in the Luquillo Experimental Forest, Puerto Rico.

    Science.gov (United States)

    Hongqing Wang; Joseph D. Cornell; Charles A.S. Hall; David P. Marley

    2002-01-01

    We developed a spatially-explicit version of the CENTURY soil model to characterize the storage and flux of soil organic carbon (SOC, 0–30 cm depth) in the Luquillo Experimental Forest (LEF), Puerto Rico as a function of climate, vegetation, and soils. The model was driven by monthly estimates of average air temperature, precipitation, and potential evapotranspiration...

  6. Effects of tree species on soil properties in a forest of the Northeastern United States

    NARCIS (Netherlands)

    Dijkstra, F.A.

    2001-01-01

    Large differences in soil pH and available Ca in the surface soil exist among tree species growing in a mixed hardwood forest in northwestern Connecticut. The observed association between tree species and specific soil chemical properties within mixed-species stands implies that changes in

  7. Conversion of Forests to Arable Land and its Effect on Soil Physical ...

    African Journals Online (AJOL)

    Prof. Ogunji

    Conversion of Forests to Arable Land and its Effect on Soil ... greater hydraulic conductivity than those under cultivation and this may indicate greater pore ... stability and clay dispersion index were 10% higher and 28% lower in the .... degraded the physical properties, making the soil more prone to soil erosion by water.

  8. The role of organic matter as a source of nitrogen in Douglas-fir forest soils.

    Science.gov (United States)

    Robert F. Tarrant

    1948-01-01

    The organic material supplied the forest soil by deposits of needles, deadwood and roots, and soil insect remains, decomposes to form humus, defined as the plant and animal residues of the soil, fresh surface litter excluded, which are undergoing evident decomposition (2). This decomposition is necessary before the nutrient elements contained in the organic litter can...

  9. Measuring environmental change in forest ecosystems by repeated soil sampling: A North American perspective

    Science.gov (United States)

    Gregory B. Lawrence; Ivan J. Fernandez; Daniel D. Richter; Donald S. Ross; Paul W. Hazlett; Scott W. Bailey; Rock Ouimet; Richard A. F. Warby; Arthur H. Johnson; Henry Lin; James M. Kaste; Andrew G. Lapenis; Timothy J. Sullivan

    2013-01-01

    Environmental change is monitored in North America through repeated measurements of weather, stream and river flow, air and water quality, and most recently, soil properties. Some skepticism remains, however, about whether repeated soil sampling can effectively distinguish between temporal and spatial variability, and efforts to document soil change in forest...

  10. CO2 deficit in temperate forest soils receiving high atmospheric N-deposition.

    Science.gov (United States)

    Fleischer, Siegfried

    2003-02-01

    Evidence is provided for an internal CO2 sink in forest soils, that may have a potential impact on the global CO2-budget. Lowered CO2 fraction in the soil atmosphere, and thus lowered CO2 release to the aboveground atmosphere, is indicated in high N-deposition areas. Also at forest edges, especially of spruce forest, where additional N-deposition has occurred, the soil CO2 is lowered, and the gradient increases into the closed forest. Over the last three decades the capacity of the forest soil to maintain the internal sink process has been limited to a cumulative supply of approximately 1000 and 1500 kg N ha(-1). Beyond this limit the internal soil CO2 sink becomes an additional CO2 source, together with nitrogen leaching. This stage of "nitrogen saturation" is still uncommon in closed forests in southern Scandinavia, however, it occurs in exposed forest edges which receive high atmospheric N-deposition. The soil CO2 gradient, which originally increases from the edge towards the closed forest, becomes reversed.

  11. Effect of Simulated N Deposition on Soil Exchangeable Cations in Three Forest Types of Subtropical China

    Institute of Scientific and Technical Information of China (English)

    LU Xian-Kai; MO Jiang-Ming; P.GUNDERSERN; ZHU Wei-Xing; ZHOU Guo-Yi; LI De-Jun; ZHANG Xu

    2009-01-01

    The effects of simulated nitrogen (N) deposition on soil exchangeable cations were studied in three forest types of subtropical China.Four N treatments with three replications were designed for the monsoon evergreen broadleaf forest (mature forest):control (0 kg N ha-1 year-1),low N (50 kg N ha-1 year-1),medium N (100 kg N ha-1 year-1) and high N (150 kg N ha-1 ycar-1),and only three treatments (i.e.,control,low N,medium N) were established for the pine and mixed forests.Nitrogen had been applied continuously for 26 months before the measurement.The mature forest responded more rapidly and intensively to N additions than the pine and mixed forests,and exhibited some significant negative symptoms,e.g.,soil acidification,Al mobilization and leaching of base cations from soil.The pine and mixed forests responded slowly to N additions and exhibited no significant response of soil cations.Response of soil exchangeable cations to N deposition varied in the forests of subtropical China,depending on soil N status and land-nse history.

  12. Forest Structure Affects Soil Mercury Losses in the Presence and Absence of Wildfire.

    Science.gov (United States)

    Homann, Peter S; Darbyshire, Robyn L; Bormann, Bernard T; Morrissette, Brett A

    2015-11-03

    Soil is an important, dynamic component of regional and global mercury (Hg) cycles. This study evaluated how changes in forest soil Hg masses caused by atmospheric deposition and wildfire are affected by forest structure. Pre and postfire soil Hg measurements were made over two decades on replicate experimental units of three prefire forest structures (mature unthinned, mature thinned, clear-cut) in Douglas-fir dominated forest of southwestern Oregon. In the absence of wildfire, O-horizon Hg decreased by 60% during the 14 years after clearcutting, possibly the result of decreased atmospheric deposition due to the smaller-stature vegetative canopy; in contrast, no change was observed in mature unthinned and thinned forest. Wildfire decreased O-horizon Hg by >88% across all forest structures and decreased mineral-soil (0 to 66 mm depth) Hg by 50% in thinned forest and clear-cut. The wildfire-associated soil Hg loss was positively related to the amount of surface fine wood that burned during the fire, the proportion of area that burned at >700 °C, fire severity as indicated by tree mortality, and soil C loss. Loss of soil Hg due to the 200,000 ha wildfire was more than four times the annual atmospheric Hg emissions from human activities in Oregon.

  13. The effect of increasing salinity and forest mortality on soil nitrogen and phosphorus mineralization in tidal freshwater forested wetlands

    Science.gov (United States)

    Noe, Gregory B.; Krauss, Ken W.; Lockaby, B. Graeme; Conner, William H.; Hupp, Cliff R.

    2013-01-01

    Tidal freshwater wetlands are sensitive to sea level rise and increased salinity, although little information is known about the impact of salinification on nutrient biogeochemistry in tidal freshwater forested wetlands. We quantified soil nitrogen (N) and phosphorus (P) mineralization using seasonal in situ incubations of modified resin cores along spatial gradients of chronic salinification (from continuously freshwater tidal forest to salt impacted tidal forest to oligohaline marsh) and in hummocks and hollows of the continuously freshwater tidal forest along the blackwater Waccamaw River and alluvial Savannah River. Salinification increased rates of net N and P mineralization fluxes and turnover in tidal freshwater forested wetland soils, most likely through tree stress and senescence (for N) and conversion to oligohaline marsh (for P). Stimulation of N and P mineralization by chronic salinification was apparently unrelated to inputs of sulfate (for N and P) or direct effects of increased soil conductivity (for N). In addition, the tidal wetland soils of the alluvial river mineralized more P relative to N than the blackwater river. Finally, hummocks had much greater nitrification fluxes than hollows at the continuously freshwater tidal forested wetland sites. These findings add to knowledge of the responses of tidal freshwater ecosystems to sea level rise and salinification that is necessary to predict the consequences of state changes in coastal ecosystem structure and function due to global change, including potential impacts on estuarine eutrophication.

  14. Soil dehydrogenase activity of natural macro aggregates in a toposequence of forest soil

    Directory of Open Access Journals (Sweden)

    Maira Kussainova

    2013-01-01

    Full Text Available The main objective of this study was to determine changes in soil dehydrogenase activity in natural macro aggregates development along a slope in forest soils. This study was carried out in Kocadag, Samsun, Turkey. Four landscape positions i.e., summit, shoulder backslope and footslope, were selected. For each landseape position, soil macro aggregates were separated into six aggregate size classes using a dry sieving method and then dehydrogenase activity was analyzed. In this research, topography influenced the macroaggregate size and dehydrogenase activity within the aggregates. At all landscape positions, the contents of macro aggregates (especially > 6.3 mm and 2.00–4.75 mm in all soil samples were higher than other macro aggregate contents. In footslope position, the soils had generally the higher dehydrogenase activity than the other positions at all landscape positions. In all positions, except for shoulder, dehydrogenase activity was greater macro aggregates of <1 mm than in the other macro aggregate size.

  15. Responses of soil fungi to logging and oil palm agriculture in Southeast Asian tropical forests.

    Science.gov (United States)

    McGuire, K L; D'Angelo, H; Brearley, F Q; Gedallovich, S M; Babar, N; Yang, N; Gillikin, C M; Gradoville, R; Bateman, C; Turner, B L; Mansor, P; Leff, J W; Fierer, N

    2015-05-01

    Human land use alters soil microbial composition and function in a variety of systems, although few comparable studies have been done in tropical forests and tropical agricultural production areas. Logging and the expansion of oil palm agriculture are two of the most significant drivers of tropical deforestation, and the latter is most prevalent in Southeast Asia. The aim of this study was to compare soil fungal communities from three sites in Malaysia that represent three of the most dominant land-use types in the Southeast Asia tropics: a primary forest, a regenerating forest that had been selectively logged 50 years previously, and a 25-year-old oil palm plantation. Soil cores were collected from three replicate plots at each site, and fungal communities were sequenced using the Illumina platform. Extracellular enzyme assays were assessed as a proxy for soil microbial function. We found that fungal communities were distinct across all sites, although fungal composition in the regenerating forest was more similar to the primary forest than either forest community was to the oil palm site. Ectomycorrhizal fungi, which are important associates of the dominant Dipterocarpaceae tree family in this region, were compositionally distinct across forests, but were nearly absent from oil palm soils. Extracellular enzyme assays indicated that the soil ecosystem in oil palm plantations experienced altered nutrient cycling dynamics, but there were few differences between regenerating and primary forest soils. Together, these results show that logging and the replacement of primary forest with oil palm plantations alter fungal community and function, although forests regenerating from logging had more similarities with primary forests in terms of fungal composition and nutrient cycling potential. Since oil palm agriculture is currently the mostly rapidly expanding equatorial crop and logging is pervasive across tropical ecosystems, these findings may have broad applicability.

  16. Prediction of Soil Erosion Rates in Japan where Heavily Forested Landscape with Unstable Terrain

    Science.gov (United States)

    Nanko, K.; Oguro, M.; Miura, S.; Masaki, T.

    2016-12-01

    Soil is fundamental for plant growth, water conservation, and sustainable forest management. Multidisciplinary interest in the role of the soil in areas such as biodiversity, ecosystem services, land degradation, and water security has been growing (Miura et al., 2015). Forest is usually protective land use from soil erosion because vegetation buffers rainfall power and erosivity. However, some types of forest in Japan show high susceptibility to soil erosion due to little ground cover and steep slopes exceeding thirty degree, especially young Japanese cypress (Chamaecyparis obtusa) plantations (Miura et al., 2002). This is a critical issue for sustainable forest management because C. obtusaplantations account for 10% of the total forest coverage in Japan (Forestry Agency, 2009). Prediction of soil erosion rates on nationwide scale is necessary to make decision for future forest management plan. To predict and map soil erosion rates across Japan, we applied three soil erosion models, RUSLE (Revised Universal Soil Loss Equation, Wischmeier and Smith, 1978), PESERA (Pan-European Soil Erosion Risk Assessment, Kirkby et al., 2003), and RMMF (Revised Morgan-Morgan-Finney, Morgan, 2001). The grid scale is 1-km. RUSLE and PESERA are most widely used erosion models today. RMMF includes interactions between rainfall and vegetation, such as canopy interception and ratio of canopy drainage in throughfall. Evaporated rainwater by canopy interception, generally accounts for 15-20% in annual rainfall, does not contribute soil erosion. Whereas, larger raindrops generated by canopy drainage produced higher splash erosion rates than gross rainfall (Nanko et al., 2008). Therefore, rainfall redistribution process in canopy should be considered to predict soil erosion rates in forested landscape. We compared the results from three erosion models and analyze the importance of environmental factors for the prediction of soil erosion rates. This research was supported by the Environment

  17. Soil carbon storage following road removal and timber harvesting in redwood forests

    Science.gov (United States)

    Seney, Joseph; Madej, Mary Ann

    2015-01-01

    Soil carbon storage plays a key role in the global carbon cycle and is important for sustaining forest productivity. Removal of unpaved forest roads has the potential for increasing carbon storage in soils on forested terrain as treated sites revegetate and soil properties improve on the previously compacted road surfaces. We compared soil organic carbon (SOC) content at several depths on treated roads to SOC in adjacent second-growth forests and old-growth redwood forests in California, determined whether SOC in the upper 50 cm of soil varies with the type of road treatment, and assessed the relative importance of site-scale and landscape-scale variables in predicting SOC accumulation in treated road prisms and second-growth redwood forests. Soils were sampled at 5, 20, and 50 cm depths on roads treated by two methods (decommissioning and full recontouring), and in adjacent second-growth and old-growth forests in north coastal California. Road treatments spanned a period of 32 years, and covered a range of geomorphic and vegetative conditions. SOC decreased with depth at all sites. Treated roads on convex sites exhibited higher SOC than on concave sites, and north aspect sites had higher SOC than south aspect sites. SOC at 5, 20, and 50 cm depths did not differ significantly between decommissioned roads (treated 18–32 years previous) and fully recontoured roads (treated 2–12 years previous). Nevertheless, stepwise multiple regression models project higher SOC developing on fully recontoured roads in the next few decades. The best predictors for SOC on treated roads and in second-growth forest incorporated aspect, vegetation type, soil depth, lithology, distance from the ocean, years since road treatment (for the road model) and years since harvest (for the forest model). The road model explained 48% of the variation in SOC in the upper 50 cm of mineral soils and the forest model, 54%

  18. Forest Soil Bacteria: Diversity, Involvement in Ecosystem Processes, and Response to Global Change.

    Science.gov (United States)

    Lladó, Salvador; López-Mondéjar, Rubén; Baldrian, Petr

    2017-06-01

    The ecology of forest soils is an important field of research due to the role of forests as carbon sinks. Consequently, a significant amount of information has been accumulated concerning their ecology, especially for temperate and boreal forests. Although most studies have focused on fungi, forest soil bacteria also play important roles in this environment. In forest soils, bacteria inhabit multiple habitats with specific properties, including bulk soil, rhizosphere, litter, and deadwood habitats, where their communities are shaped by nutrient availability and biotic interactions. Bacteria contribute to a range of essential soil processes involved in the cycling of carbon, nitrogen, and phosphorus. They take part in the decomposition of dead plant biomass and are highly important for the decomposition of dead fungal mycelia. In rhizospheres of forest trees, bacteria interact with plant roots and mycorrhizal fungi as commensalists or mycorrhiza helpers. Bacteria also mediate multiple critical steps in the nitrogen cycle, including N fixation. Bacterial communities in forest soils respond to the effects of global change, such as climate warming, increased levels of carbon dioxide, or anthropogenic nitrogen deposition. This response, however, often reflects the specificities of each studied forest ecosystem, and it is still impossible to fully incorporate bacteria into predictive models. The understanding of bacterial ecology in forest soils has advanced dramatically in recent years, but it is still incomplete. The exact extent of the contribution of bacteria to forest ecosystem processes will be recognized only in the future, when the activities of all soil community members are studied simultaneously. Copyright © 2017 American Society for Microbiology.

  19. Effects of artificial defoliation of pines on the structure and physiology of the soil fungal community of a mixed pine-spruce forest

    Science.gov (United States)

    Cullings, Ken; Raleigh, Christopher; New, Michael H.; Henson, Joan

    2005-01-01

    Loss of photosynthetic area can affect soil microbial communities by altering the availability of fixed carbon. We used denaturing gradient gel electrophoresis (DGGE) and Biolog filamentous-fungus plates to determine the effects of artificial defoliation of pines in a mixed pine-spruce forest on the composition of the fungal community in a forest soil. As measured by DGGE, two fungal species were affected significantly by the defoliation of pines (P soil fungus increased. The decrease in the amount of Cenococcum organisms may have occurred because of the formation of extensive hyphal networks by species of this genus, which require more of the carbon fixed by their host, or because this fungus is dependent upon quantitative differences in spruce root exudates. The defoliation of pines did not affect the overall composition of the soil fungal community or fungal-species richness (number of species per core). Biolog filamentous-fungus plate assays indicated a significant increase (P soil fungi and the rate at which these substrates were used, which could indicate an increase in fungal-species richness. Thus, either small changes in the soil fungal community give rise to significant increases in physiological capabilities or PCR bias limits the reliability of the DGGE results. These data indicate that combined genetic and physiological assessments of the soil fungal community are needed to accurately assess the effect of disturbance on indigenous microbial systems.

  20. Final Progress Report on Model-Based Diagnosis of Soil Limitations to Forest Productivity

    Energy Technology Data Exchange (ETDEWEB)

    Luxmoore, R.J.

    2004-08-30

    This project was undertaken in support of the forest industry to link modeling of nutrients and productivity with field research to identify methods for enhancing soil quality and forest productivity and for alleviating soil limitations to sustainable forest productivity. The project consisted of a series of related tasks, including (1) simulation of changes in biomass and soil carbon with nitrogen fertilization, (2) development of spreadsheet modeling tools for soil nutrient availability and tree nutrient requirements, (3) additional modeling studies, and (4) evaluation of factors involved in the establishment and productivity of southern pine plantations in seasonally wet soils. This report also describes the two Web sites that were developed from the research to assist forest managers with nutrient management of Douglas-fir and loblolly pine plantations.

  1. Soil Microbial Biomass, Basal Respiration and Enzyme Activity of Main Forest Types in the Qinling Mountains

    Science.gov (United States)

    Cheng, Fei; Peng, Xiaobang; Zhao, Peng; Yuan, Jie; Zhong, Chonggao; Cheng, Yalong; Cui, Cui; Zhang, Shuoxin

    2013-01-01

    Different forest types exert essential impacts on soil physical-chemical characteristics by dominant tree species producing diverse litters and root exudates, thereby further regulating size and activity of soil microbial communities. However, the study accuracy is usually restricted by differences in climate, soil type and forest age. Our objective is to precisely quantify soil microbial biomass, basal respiration and enzyme activity of five natural secondary forest (NSF) types with the same stand age and soil type in a small climate region and to evaluate relationship between soil microbial and physical-chemical characters. We determined soil physical-chemical indices and used the chloroform fumigation-extraction method, alkali absorption method and titration or colorimetry to obtain the microbial data. Our results showed that soil physical-chemical characters remarkably differed among the NSFs. Microbial biomass carbon (Cmic) was the highest in wilson spruce soils, while microbial biomass nitrogen (Nmic) was the highest in sharptooth oak soils. Moreover, the highest basal respiration was found in the spruce soils, but mixed, Chinese pine and spruce stands exhibited a higher soil qCO2. The spruce soils had the highest Cmic/Nmic ratio, the greatest Nmic/TN and Cmic/Corg ratios were found in the oak soils. Additionally, the spruce soils had the maximum invertase activity and the minimum urease and catalase activities, but the maximum urease and catalase activities were found in the mixed stand. The Pearson correlation and principle component analyses revealed that the soils of spruce and oak stands obviously discriminated from other NSFs, whereas the others were similar. This suggested that the forest types affected soil microbial properties significantly due to differences in soil physical-chemical features. PMID:23840671

  2. Shifts in Plant Assemblages Reduce the Richness of Galling Insects Across Edge-Affected Habitats in the Atlantic Forest.

    Science.gov (United States)

    Souza, Danielle G; Santos, Jean C; Oliveira, Marcondes A; Tabarelli, Marcelo

    2016-10-01

    Impacts of habitat loss and fragmentation on specialist herbivores have been rarely addressed. Here we examine the structure of plant and galling insect assemblages in a fragmented landscape of the Atlantic forest to verify a potential impoverishment of these assemblages mediated by edge effects. Saplings and galling insects were recorded once within a 0.1-ha area at habitat level, covering forest interior stands, forest edges, and small fragments. A total of 1,769 saplings from 219 tree species were recorded across all three habitats, with differences in terms of sapling abundance and species richness. Additionally, edge-affected habitats exhibited reduced richness of both host-plant and galling insects at plot and habitat spatial scale. Attack levels also differed among forest types at habitat spatial scale (21.1% of attacked stems in forest interior, 12.4% in small fragments but only 8.5% in forest edges). Plot ordination resulted in three clearly segregated clusters: one formed by forest interior, one by small fragments, and another formed by edge plots. Finally, the indicator species analysis identified seven and one indicator plant species in forest interior and edge-affected habitats, respectively. Consequently, edge effects lead to formation of distinct taxonomic groups and also an impoverished assemblage of plants and galling insects at multiple spatial scales. The results of the present study indicate that fragmentation-related changes in plant assemblages can have a cascade effects on specialist herbivores. Accordingly, hyperfragmented landscapes may not be able to retain an expressive portion of tropical biodiversity. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Biodiversity Differences between Managed and Unmanaged Forests: Meta-Analysis of Species Richness in Europe

    NARCIS (Netherlands)

    Paillet, Y.; Bergès, L.; Hjältén, J.; Ódor, P.; Avon, C.; Bernhardt-Römermann, M.; Bijlsma, R.J.; Bruyn, de L.; Fuhr, M.; Grandin, U.; Kanka, R.; Lundin, L.; Luque, S.; Magura, T.; Matesanz, S.; Mészáros, I.; Sebastià, M.T.; Schmidt, W.; Standovár, T.; Tóthmérész, B.; Uotila, A.; Valladares, F.; Vellak, K.; Virtanen, R.

    2010-01-01

    Past and present pressures on forest resources have led to a drastic decrease in the surface area of unmanaged forests in Europe. Changes in forest structure, composition, and dynamics inevitably lead to changes in the biodiversity of forest-dwelling species. The possible biodiversity gains and

  4. Contrasting the microbiomes from forest rhizosphere and deeper bulk soil from an Amazon rainforest reserve.

    Science.gov (United States)

    Fonseca, Jose Pedro; Hoffmann, Luisa; Cabral, Bianca Catarina Azeredo; Dias, Victor Hugo Giordano; Miranda, Marcio Rodrigues; de Azevedo Martins, Allan Cezar; Boschiero, Clarissa; Bastos, Wanderley Rodrigues; Silva, Rosane

    2018-02-05

    Pristine forest ecosystems provide a unique perspective for the study of plant-associated microbiota since they host a great microbial diversity. Although the Amazon forest is one of the hotspots of biodiversity around the world, few metagenomic studies described its microbial community diversity thus far. Understanding the environmental factors that can cause shifts in microbial profiles is key to improving soil health and biogeochemical cycles. Here we report a taxonomic and functional characterization of the microbiome from the rhizosphere of Brosimum guianense (Snakewood), a native tree, and bulk soil samples from a pristine Brazilian Amazon forest reserve (Cuniã), for the first time by the shotgun approach. We identified several fungi and bacteria taxon significantly enriched in forest rhizosphere compared to bulk soil samples. For archaea, the trend was the opposite, with many archaeal phylum and families being considerably more enriched in bulk soil compared to forest rhizosphere. Several fungal and bacterial decomposers like Postia placenta and Catenulispora acidiphila which help maintain healthy forest ecosystems were found enriched in our samples. Other bacterial species involved in nitrogen (Nitrobacter hamburgensis and Rhodopseudomonas palustris) and carbon cycling (Oligotropha carboxidovorans) were overrepresented in our samples indicating the importance of these metabolic pathways for the Amazon rainforest reserve soil health. Hierarchical clustering based on taxonomic similar microbial profiles grouped the forest rhizosphere samples in a distinct clade separated from bulk soil samples. Principal coordinate analysis of our samples with publicly available metagenomes from the Amazon region showed grouping into specific rhizosphere and bulk soil clusters, further indicating distinct microbial community profiles. In this work, we reported significant shifts in microbial community structure between forest rhizosphere and bulk soil samples from an Amazon

  5. Human impacts on soil carbon dynamics of deep-rooted Amazonian forests

    Science.gov (United States)

    Nepstad, Daniel C.; Stone, Thomas A.; Davidson, Eric A.

    1994-01-01

    Deforestation and logging degrade more forest in eastern and southern Amazonia than in any other region of the world. This forest alteration affects regional hydrology and the global carbon cycle, but our current understanding of these effects is limited by incomplete knowledge of tropical forest ecosystems. It is widely agreed that roots are concentrated near the soil surface in moist tropical forests, but this generalization incorrectly implies that deep roots are unimportant in water and C budgets. Our results indicate that half of the closed-canopy forests of Brazilian Amazonic occur where rainfall is highly seasonal, and these forests rely on deeply penetrating roots to extract soil water. Pasture vegetation extracts less water from deep soil than the forest it replaces, thus increasing rates of drainage and decreasing rates of evapotranspiration. Deep roots are also a source of modern carbon deep in the soil. The soils of the eastern Amazon contain more carbon below 1 m depth than is present in above-ground biomass. As much as 25 percent of this deep soil C could have annual to decadal turnover times and may be lost to the atmosphere following deforestation. We compared the importance of deep roots in a mature, evergreen forest with an adjacent man-made pasture, the most common type of vegetation on deforested land in Amazonia. The study site is near the town of Paragominas, in the Brazilian state of Para, with a seasonal rainfall pattern and deeply-weathered, kaolinitic soils that are typical for large portions of Amazonia. Root distribution, soil water extraction, and soil carbon dynamics were studied using deep auger holes and shafts in each ecosystem, and the phenology and water status of the leaf canopies were measured. We estimated the geographical distribution of deeply-rooting forests using satellite imagery, rainfall data, and field measurements.

  6. Soil changes induced by rubber and tea plantation establishment: comparison with tropical rain forest soil in Xishuangbanna, SW China.

    Science.gov (United States)

    Li, Hongmei; Ma, Youxin; Liu, Wenjie; Liu, Wenjun

    2012-11-01

    Over the past thirty years, Xishuangbanna in Southwestern China has seen dramatic changes in land use where large areas of tropical forest and fallow land have been converted to rubber and tea plantations. In this study we evaluated the effects of land use and slope on soil properties in seven common disturbed and undisturbed land-types. Results indicated that all soils were acidic, with pH values significantly higher in the 3- and 28-year-old rubber plantations. The tropical forests had the lowest bulk densities, especially significantly lower from the top 10 cm of soil, and highest soil organic matter concentrations. Soil moisture content at topsoil was highest in the mature rubber plantation. Soils in the tropical forests and abandoned cultivated land had inorganic N (IN) concentrations approximately equal in NH(4) (+)-N and NO(3) (-)-N. However, soil IN pools were dominated by NH(4) (+)-N in the rubber and tea plantations. This trend suggests that conversion of tropical forest to rubber and tea plantations increases NH(4) (+)-N concentration and decreases NO(3) (-)-N concentration, with the most pronounced effect in plantations that are more frequently fertilized. Soil moisture content, IN, NH(4) (+)-N and NO(3) (-)-N concentrations within all sites were higher in the rainy season than in the dry season. Significant differences in the soil moisture content, and IN, NH(4) (+)-N and NO(3) (-)-N concentration was detected for both land uses and sampling season effects, as well as interactions. Higher concentrations of NH(4) (+)-N were measured at the upper slopes of all sites, but NO(3) (-)-N concentrations were highest at the lower slope in the rubber plantations and lowest at the lower slopes at all other. Thus, the conversion of tropical forests to rubber and tea plantations can have a profound effect on soil NH(4) (+)-N and NO(3) (-)-N concentrations. Options for improved soil management in plantations are discussed.

  7. The technology of layer-specific rotary soil cultivation for forest crops and equipment for its implementation

    Directory of Open Access Journals (Sweden)

    S. N. Orlovskiy

    2017-06-01

    unnecessary, and cleaning, ploughing furrows, planting and further tending seedlings are not needed. Soil layers are not mixed, as within usual tillage. Rich soil layer is not withdrawn, so that germination ability of target seeds increases, and growth of seedlings in enhanced. The entire process takes much less energy compared to traditional technologies. Application of the device increases the quality of forest regeneration and reduces labor input owing to the new technology.

  8. Assessing Bioenergy Harvest Risks: Geospatially Explicit Tools for Maintaining Soil Productivity in Western US Forests

    Directory of Open Access Journals (Sweden)

    Deborah Page-Dumroese

    2011-09-01

    Full Text Available Biomass harvesting for energy production and forest health can impact the soil resource by altering inherent chemical, physical and biological properties. These impacts raise concern about damaging sensitive forest soils, even with the prospect of maintaining vigorous forest growth through biomass harvesting operations. Current forest biomass harvesting research concurs that harvest impacts to the soil resource are region- and site-specific, although generalized knowledge from decades of research can be incorporated into management activities. Based upon the most current forest harvesting research, we compiled information on harvest activities that decrease, maintain or increase soil-site productivity. We then developed a soil chemical and physical property risk assessment within a geographic information system for a timber producing region within the Northern Rocky Mountain ecoregion. Digital soil and geology databases were used to construct geospatially explicit best management practices to maintain or enhance soil-site productivity. The proposed risk assessments could aid in identifying resilient soils for forest land managers considering biomass operations, policy makers contemplating expansion of biomass harvesting and investors deliberating where to locate bioenergy conversion facilities.

  9. Sorption and Transport of Pharmaceutical chemicals in Organic- and Mineral-rich Soils

    Science.gov (United States)

    Vulava, V. M.; Schwindaman, J.; Murphey, V.; Kuzma, S.; Cory, W.

    2011-12-01

    Pharmaceutical, active ingredients in personal care products (PhACs), and their derivative compounds are increasingly ubiquitous in surface waters across the world. Sorption and transport of four relatively common PhACs (naproxen, ibuprofen, cetirizine, and triclosan) in different natural soils was measured. All of these compounds are relatively hydrophobic (log KOW>2) and have acid/base functional groups, including one compound that is zwitterionic (cetirizine.) The main goal of this study was to correlate organic matter (OM) and clay content in natural soils and sediment with sorption and degradation of PhACs and ultimately their potential for transport within the subsurface environment. A- and B-horizon soils were collected from four sub-regions within a pristine managed forested watershed near Charleston, SC, with no apparent sources of anthropogenic contamination. These four soil series had varying OM content (fOC) between 0.4-9%, clay mineral content between 6-20%, and soil pH between 4.5-6. The A-horizon soils had higher fOC and lower clay content than the B-horizon soils. Sorption isotherms measured from batch sorption experimental data indicated a non-linear sorption relationship in all A- and B-horizon soils - stronger sorption was observed at lower PhAC concentrations and lower sorption at higher concentrations. Three PhACs (naproxen, ibuprofen, and triclosan) sorbed more strongly with higher fOC A-horizon soils compared with the B-horizon soils. These results show that soil OM had a significant role in strongly binding these three PhACs, which had the highest KOW values. In contrast, cetirizine, which is predominantly positively charged at pH below 8, strongly sorbed to soils with higher clay mineral content and least strongly to higher fOC soils. All sorption isotherms fitted well to the Freundlich model. For naproxen, ibuprofen, and triclosan, there was a strong and positive linear correlation between the Freundlich adsorption constant, Kf, and f

  10. Forest thinning and soil respiration in a ponderosa pine plantation in the Sierra Nevada.

    Science.gov (United States)

    Tang, Jianwu; Qi, Ye; Xu, Ming; Misson, Laurent; Goldstein, Allen H

    2005-01-01

    Soil respiration is controlled by soil temperature, soil water, fine roots, microbial activity, and soil physical and chemical properties. Forest thinning changes soil temperature, soil water content, and root density and activity, and thus changes soil respiration. We measured soil respiration monthly and soil temperature and volumetric soil water continuously in a young ponderosa pine (Pinus ponderosa Dougl. ex P. Laws. & C. Laws.) plantation in the Sierra Nevada Mountains in California from June 1998 to May 2000 (before a thinning that removed 30% of the biomass), and from May to December 2001 (after thinning). Thinning increased the spatial homogeneity of soil temperature and respiration. We conducted a multivariate analysis with two independent variables of soil temperature and water and a categorical variable representing the thinning event to simulate soil respiration and assess the effect of thinning. Thinning did not change the sensitivity of soil respiration to temperature or to water, but decreased total soil respiration by 13% at a given temperature and water content. This decrease in soil respiration was likely associated with the decrease in root density after thinning. With a model driven by continuous soil temperature and water time series, we estimated that total soil respiration was 948, 949 and 831 g C m(-2) year(-1) in the years 1999, 2000 and 2001, respectively. Although thinning reduced soil respiration at a given temperature and water content, because of natural climate variability and the thinning effect on soil temperature and water, actual cumulative soil respiration showed no clear trend following thinning. We conclude that the effect of forest thinning on soil respiration is the combined result of a decrease in root respiration, an increase in soil organic matter, and changes in soil temperature and water due to both thinning and interannual climate variability.

  11. Magnetic minerals in soils across the forest-prairie ecotone in NW Minnesota

    Science.gov (United States)

    Maxbauer, D.; Feinberg, J. M.; Fox, D. L.; Nater, E. A.

    2016-12-01

    Soil pedogenesis results in a complex assemblage of iron oxide minerals that can be disentangled successfully using sensitive magnetic techniques to better delineate specific soil processes. Here, we evaluate the variability in soil processes within forest, prairie, and transitional soils along an 11 km transect of anthropogenically unaltered soils that span the forest-to-prairie ecotone in NW Minnesota. All soils in this study developed on relatively uniform topography, similar glacial till parent material, under a uniform climate, and presumably over similar time intervals. The forest-to-prairie transition zone in this region is controlled by naturally occurring fires, affording the opportunity to evaluate differences in soil processes related to vegetation (forest versus prairie) and burning (prairie and transitional soils). Results suggest that the pedeogenic fraction of magnetite/maghemite in soils is similar in all specimens and is independent of soil type, vegetation, and any effects of burning. Magnetically enhanced horizons have 45% of remanence held by a low-coercivity pedogenic component (likely magnetite/maghemite) regardless of vegetation cover and soil type. Enhancement ratios for magnetic susceptibility and low-field remanences, often used as indicators of pedogenic magnetic minerals, are more variable but remain statistically equivalent across the transect. These results support the hypothesis that pedogenic magnetic minerals in soils mostly reflect ambient climatic conditions regardless of the variability in soil processes related to vegetation and soil type. The non-pedogenic magnetic mineral assemblage shows clear distinctions between the forest, prairie, and transitional soils in hysteresis properties (remanence and coercivity ratios; Mr/Ms and Bc/Bcr, respectively), suggesting that variable processes in these settings influence the local magnetic mineral assemblage, and that it may be possible to use magnetic minerals in paleosols to constrain

  12. Drivers of methane uptake by montane forest soils in the Peruvian Andes

    Science.gov (United States)

    Jones, Sam; Diem, Torsten; Huaraca Quispe, Lidia; Cahuana, Adan; Meir, Patrick; Teh, Yit

    2016-04-01

    The exchange of methane between the soils of humid tropical forests and the atmosphere is relatively poorly documented. This is particularly true of montane settings where variations between uptake and emission of atmospheric methane have been observed. Whilst most of these ecosystems appear to function as net sinks for atmospheric methane, some act as considerable sources. In regions like the Andes, humid montane forests are extensive and a better understanding of the magnitude and controls on soil-atmosphere methane exchange is required. We report methane fluxes from upper montane cloud forest (2811 - 2962 m asl), lower montane cloud forest (1532 - 1786 m asl), and premontane forest (1070 - 1088 m asl) soils in south-eastern Peru. Between 1000 and 3000 m asl, mean annual air temperature and total annual precipitation decrease from 24 ° C and 5000 mm to 12 ° C and 1700 mm. The study region experiences a pronounced wet season between October and April. Monthly measurements of soil-atmosphere gas exchange, soil moisture, soil temperature, soil oxygen concentration, available ammonium and available nitrate were made from February 2011 in the upper and lower montane cloud forests and July 2011 in the premontane forest to June 2013. These soils acted as sinks for atmospheric methane with mean net fluxes for wet and dry season, respectively, of -2.1 (0.2) and -1.5 (0.1) mg CH4 m-2 d-1 in the upper montane forest; -1.5 (0.2) and -1.4 (0.1) mg CH4 m-2 d-1in the lower montane forest; and -0.3 (0.2) and -0.2 (0.2) mg CH4 m-2 d-1 in the premontane forest. Spatial variations among forest types were related to available nitrate and water-filled pore space suggesting that nitrate inhibition of oxidation or constraints on the diffusional supply of methane to methanotrophic communities may be important controls on methane cycling in these soils. Seasonality in methane exchange, with weaker uptake related to increased water-filled pore space and soil temperature during the wet

  13. Organic carbon stocks and sequestration rates of forest soils in Germany.

    Science.gov (United States)

    Grüneberg, Erik; Ziche, Daniel; Wellbrock, Nicole

    2014-08-01

    The National Forest Soil Inventory (NFSI) provides the Greenhouse Gas Reporting in Germany with a quantitative assessment of organic carbon (C) stocks and changes in forest soils. Carbon stocks of the organic layer and the mineral topsoil (30 cm) were estimated on the basis of ca. 1.800 plots sampled from 1987 to 1992 and resampled from 2006 to 2008 on a nationwide grid of 8 × 8 km. Organic layer C stock estimates were attributed to surveyed forest stands and CORINE land cover data. Mineral soil C stock estimates were linked with the distribution of dominant soil types according to the Soil Map of Germany (1 : 1 000 000) and subsequently related to the forest area. It appears that the C pool of the organic layer was largely depending on tree species and parent material, whereas the C pool of the mineral soil varied among soil groups. We identified the organic layer C pool as stable although C was significantly sequestered under coniferous forest at lowland sites. The mineral soils, however, sequestered 0.41 Mg C ha(-1) yr(-1) . Carbon pool changes were supposed to depend on stand age and forest transformation as well as an enhanced biomass input. Carbon stock changes were clearly attributed to parent material and soil groups as sandy soils sequestered higher amounts of C, whereas clayey and calcareous soils showed small gains and in some cases even losses of soil C. We further showed that the largest part of the overall sample variance was not explained by fine-earth stock variances, rather by the C concentrations variance. The applied uncertainty analyses in this study link the variability of strata with measurement errors. In accordance to other studies for Central Europe, the results showed that the applied method enabled a reliable nationwide quantification of the soil C pool development for a certain period. © 2014 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.

  14. Drift and transmission FT-IR spectroscopy of forest soils: an approach to determine decomposition processes of forest litter

    International Nuclear Information System (INIS)

    Haberhauer, G.; Gerzabek, M.H.

    1999-06-01

    A method is described to characterize organic soil layers using Fourier transformed infrared spectroscopy. The applicability of FT-IR, either dispersive or transmission, to investigate decomposition processes of spruce litter in soil originating from three different forest sites in two climatic regions was studied. Spectral information of transmission and diffuse reflection FT-IR spectra was analyzed and compared. For data evaluation Kubelka Munk (KM) transformation was applied to the DRIFT spectra. Sample preparation for DRIFT is simpler and less time consuming in comparison to transmission FT-IR, which uses KBr pellets. A variety of bands characteristics of molecular structures and functional groups has been identified for these complex samples. Analysis of both transmission FT-IR and DRIFT, showed that the intensity of distinct bands is a measure of the decomposition of forest litter. Interferences due to water adsorption spectra were reduced by DRIFT measurement in comparison to transmission FT-IR spectroscopy. However, data analysis revealed that intensity changes of several bands of DRIFT and transmission FT-IR were significantly correlated with soil horizons. The application of regression models enables identification and differentiation of organic forest soil horizons and allows to determine the decomposition status of soil organic matter in distinct layers. On the basis of the data presented in this study, it may be concluded that FT-IR spectroscopy is a powerful tool for the investigation of decomposition dynamics in forest soils. (author)

  15. Soil Properties in Natural Forest Destruction and Conversion to Agricultural Land,in Gunung Leuser National Park, North Sumatera Province

    Directory of Open Access Journals (Sweden)

    Basuki Wasis

    2012-12-01

    Full Text Available Destruction of the Gunung Leuser National Park area of North Sumatera Province through land clearing and land cover change from natural forest to agricultural land. Less attention to land use and ecosystem carrying capacity of the soil can cause soil degradation and destruction of flora, fauna, and wildlife habitat destruction. Environmental damage will result in a national park wild life will come out of the conservation area and would damage the agricultural community. Soil sampling conducted in purposive sampling in natural forest and agricultural areas.  Observation suggest that damage to the natural forest vegetation has caused the soil is not protected so that erosion has occurred. Destruction of natural forest into agricultural are as has caused damage to soil physical properties, soil chemical properties, and biological soil properties significantly. Forms of soil degradation caused by the destruction of natural forests, which is an increase in soil density (density Limbak by 103%, a decrease of 93% organic C and soil nitrogen decreased by 81%. The main factors causing soil degradation is the reduction of organic matter and soil erosion due to loss of natural forest vegetation.  Criteria for soil degradation in Governance Regulation Number 150/2000 can be used to determine the extent of soil degradation in natural forest ecosystems.Keywords: Gunung Leuser National Park, natural forest, agricultural land, land damage, soil properties

  16. 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

  17. Structure of the tree stratum of three swamp forest communities in southern Brazil under different soil conditions

    Directory of Open Access Journals (Sweden)

    Luciana Carla Mancino

    2015-03-01

    Full Text Available Restinga forests are commonly known to be plant communities rather poor in tree species. This study aimed to describe and explain the association between the floristic-structural similarities and the environmental conditions in three Swamp Restinga Forest communities in southern Brazil. In 13 plots of 100 m2 each, we sampled all individual trees (circumference at breast height >12 cm and height ≥3 m. We collected soil samples in each plot for chemical and textural analyses. Phytosociological parameters were calculated and different structural variables were compared between areas. The density of individuals did not differ between areas; however, the maximum height and abundance of species differed between the site with Histosols and the other two sites with Gleysols. Further, a canonical correspondence analysis based on a matrix of vegetation and that of environmental characteristics explained 31.5% of the total variation. The high floristic and environmental heterogeneity indicate that swamp-forests can shelter many species with low frequency. Most species were generalists that were not exclusive to this type of forest. Overall, our study showed that swamp-forests within the same region can show considerable differences in composition and structure and can include species-rich communities, mostly due to the presence of species with a broader distribution in the Atlantic Rainforest domain on sites with less stressful environmental conditions and without waterlogged conditions.

  18. Energy-dispersive X-ray fluorescence analysis of organic-rich soils and sediments

    International Nuclear Information System (INIS)

    Parekh, P.P.

    1981-01-01

    A method has been developed for elemental analysis of environmental samples of soils and sediments rich in organic matter by energy-dispersive X-ray fluorescence spectrometry. It consists of three steps (i) determining the apparent concentration of elements by using calibration coefficients based on geochemical standards, (ii) subsequent assay of the total organic matter (TOM) from loss on ignition at 550 deg C, and (iii) evaluating the correct elemental concentration by normalizing for transparency from an empirical relationship. The main feature of the method is the sample analysis prior to ignition, which avoids any loss of trace elements - especially the volatile toxic elements, such as Zn, As, Se, and Pb - during heating. The method was tested on two organic-rich lake sediments (TOM> 30%). Concentrations of five elements (K, Mn, Fe, Zn, and Pb) determined by the present method and by atomic absorption spectrometry agreed within about +-10%. (author)

  19. Nutrient additions to a tropical rain forest drive substantial soil carbon dioxide losses to the atmosphere.

    Science.gov (United States)

    Cleveland, Cory C; Townsend, Alan R

    2006-07-05

    Terrestrial biosphere-atmosphere carbon dioxide (CO(2)) exchange is dominated by tropical forests, where photosynthetic carbon (C) uptake is thought to be phosphorus (P)-limited. In P-poor tropical forests, P may also limit organic matter decomposition and soil C losses. We conducted a field-fertilization experiment to show that P fertilization stimulates soil respiration in a lowland tropical rain forest in Costa Rica. In the early wet season, when soluble organic matter inputs to soil are high, P fertilization drove large increases in soil respiration. Although the P-stimulated increase in soil respiration was largely confined to the dry-to-wet season transition, the seasonal increase was sufficient to drive an 18% annual increase in CO(2) efflux from the P-fertilized plots. Nitrogen (N) fertilization caused similar responses, and the net increases in soil respiration in response to the additions of N and P approached annual soil C fluxes in mid-latitude forests. Human activities are altering natural patterns of tropical soil N and P availability by land conversion and enhanced atmospheric deposition. Although our data suggest that the mechanisms driving the observed respiratory responses to increased N and P may be different, the large CO(2) losses stimulated by N and P fertilization suggest that knowledge of such patterns and their effects on soil CO(2) efflux is critical for understanding the role of tropical forests in a rapidly changing global C cycle.

  20. Tropical forest soil microbes and climate warming: An Andean-Amazon gradient and `SWELTR'

    Science.gov (United States)

    Nottingham, A.; Turner, B. L.; Fierer, N.; Whitaker, J.; Ostle, N. J.; McNamara, N. P.; Bardgett, R.; Silman, M.; Bååth, E.; Salinas, N.; Meir, P.

    2017-12-01

    Climate warming predicted for the tropics in the coming century will result in average temperatures under which no closed canopy forest exists today. There is, therefore, great uncertainty associated with the direction and magnitude of feedbacks between tropical forests and our future climate - especially relating to the response of soil microbes and the third of global soil carbon contained in tropical forests. While warming experiments are yet to be performed in tropical forests, natural temperature gradients are powerful tools to investigate temperature effects on soil microbes. Here we draw on studies from a 3.5 km elevation gradient - and 20oC mean annual temperature gradient - in Peruvian tropical forest, to investigate how temperature affects the structure of microbial communities, microbial metabolism, enzymatic activity and soil organic matter cycling. With decreased elevation, soil microbial diversity increased and community composition shifted, from taxa associated with oligotrophic towards copiotrophic traits. A key role for temperature in shaping these patterns was demonstrated by a soil translocation experiment, where temperature-manipulation altered the relative abundance of specific taxa. Functional implications of these community composition shifts were indicated by changes in enzyme activities, the temperature sensitivity of bacterial and fungal growth rates, and the presence of temperature-adapted iso-enzymes at different elevations. Studies from a Peruvian elevation transect indicated that soil microbial communities are adapted to long-term (differences with elevation) and short-term (translocation responses) temperature changes. These findings indicate the potential for adaptation of soil microbes in tropical soils to future climate warming. However, in order to evaluate the sensitivity of these processes to climate warming in lowland forests, in situ experimentation is required. Finally, we describe SWELTR (Soil Warming Experiment in Lowland

  1. N2O production pathways in the subtropical acid forest soils in China

    International Nuclear Information System (INIS)

    Zhang Jinbo; Cai Zucong; Zhu Tongbin

    2011-01-01

    To date, N 2 O production pathways are poorly understood in the humid subtropical and tropical forest soils. A 15 N-tracing experiment was carried out under controlled laboratory conditions to investigate the processes responsible for N 2 O production in four subtropical acid forest soils (pH 2 O emission in the subtropical acid forest soils, being responsible for 56.1%, 53.5%, 54.4%, and 55.2% of N 2 O production, in the GC, GS, GB, and TC soils, respectively, under aerobic conditions (40%-52%WFPS). The heterotrophic nitrification (recalcitrant organic N oxidation) accounted for 27.3%-41.8% of N 2 O production, while the contribution of autotrophic nitrification was little in the studied subtropical acid forest soils. The ratios of N 2 O-N emission from total nitrification (heterotrophic+autotrophic nitrification) were higher than those in most previous references. The soil with the lowest pH and highest organic-C content (GB) had the highest ratio (1.63%), suggesting that soil pH-organic matter interactions may exist and affect N 2 O product ratios from nitrification. The ratio of N 2 O-N emission from heterotrophic nitrification varied from 0.02% to 25.4% due to soil pH and organic matter. Results are valuable in the accurate modeling of N2O production in the subtropical acid forest soils and global budget. - Highlights: → We studied N 2 O production pathways in subtropical acid forest soil under aerobic conditions. → Denitrification was the main source of N 2 O production in subtropical acid forest soils. → Heterotrophic nitrification accounted for 27.3%-41.8% of N 2 O production. → While, contribution of autotrophic nitrification to N 2 O production was little. → Ratios of N 2 O-N emission from nitrification were higher than those in most previous references.

  2. The accumulation of 137Cs in the biological compartment of forest soils

    International Nuclear Information System (INIS)

    Nikolova, Ivanka; Johanson, Karl J.; Clegg, Stephen

    2000-01-01

    Soil samples were collected in various forest stands, located about 40 km north-west from Uppsala. The various stands were: (1) Clear cut area made in 1987, (2) Normal forest with 50-100 old Norway spruce and Scots pine and with a thick humic layer of about 10 cm; (3) Raised bog with 50-year-old Scots pine and Sphagnum moss layer over peat soil. (4) Rocky area with old Scots pine, growing on a shallow soil, mainly of organic origin. (5) Normal forest with nearly 100-year-old spruce and pine, growing a shallow humic layer over sandy soil. Soil blocks of about 20x20 cm and down to a depth of 10-15 cm were collected on each site. The soil samples were mechanically separated into various fractions: bulk, rhizosphere and soil-root interface. The results showed that 137 Cs was unevenly distributed between the three soil fractions. The highest activity concentrations -- 3-4 times higher than in the other two fractions -- as well as the highest organic content -- usually more than 95% -- were found in the soil-root interface fraction. Of the total 137 Cs activity in the soil, 18% as a mean value was found in the soil-root interface fraction. The results thus show that a substantial fraction of the 137 Cs in the soils in some way associated with the biological part of the soil, probably with the fungal component

  3. Restoration of species-rich grasslands on ex-arable land: Seed addition outweighs soil fertility reduction

    NARCIS (Netherlands)

    Kardol, P.; Van der Wal, A.; Bezemer, T.M.; De Boer, W.; Duyts, H.; Holtkamp, R.; Van der Putten, W.H.

    2008-01-01

    A common practice in biodiversity conservation is restoration of former species-rich grassland on ex-arable land. Major constraints for grassland restoration are high soil fertility and limited dispersal ability of plant species to target sites. Usually, studies focus on soil fertility or on methods

  4. Differential responses of soil bacteria, fungi, archaea and protists to plant species richness and plant functional group identity

    NARCIS (Netherlands)

    Dassen, S.; Cortois, R.; Martens, Henk; De Hollander, M.; Kowalchuk, G.A.; van der Putten, W.H.; De Deyn, G.B.

    2017-01-01

    Plants are known to influence belowground microbial community structure along their roots, but the impacts of plant species richness and plant functional group (FG) identity on microbial communities in the bulk soil are still not well understood. Here, we used 454-pyrosequencing to analyse the soil

  5. Characteristics of CO2 release from forest soil in the mountains near Beijing.

    Science.gov (United States)

    Sun, Xiang Yang; Gao, Cheng Da; Zhang, Lin; Li, Su Yan; Qiao, Yong

    2011-04-01

    CO2 release from forest soil is a key driver of carbon cycling between the soil and atmosphere ecosystem. The rate of CO2 released from soil was measured in three forest stands (in the mountainous region near Beijing, China) by the alkaline absorption method from 2004 to 2006. The rate of CO2 released did not differ among the three stands. The CO2 release rate ranged from - 341 to 1,193 mg m(-2) h(-1), and the mean value over all three forests and sampling times was 286 mg m(-2) h(-1). CO2 release was positively correlated with soil water content and the soil temperature. Diurnally, CO2 release was higher in the day than at night. Seasonally, CO2 release was highest in early autumn and lowest in winter; in winter, negative values of CO2 release suggested that CO2 was absorbed by soil.

  6. Effect of soil carbohydrates on nutrient availability in natural forests and cultivated lands in Sri Lanka

    Science.gov (United States)

    Ratnayake, R. R.; Seneviratne, G.; Kulasooriya, S. A.

    2013-05-01

    Carbohydrates supply carbon sources for microbial activities that contribute to mineral nutrient production in soil. Their role on soil nutrient availability has not yet been properly elucidated. This was studied in forests and cultivated lands in Sri Lanka. Soil organic matter (SOM) fractions affecting carbohydrate availability were also determined. Soil litter contributed to sugars of plant origin (SPO) in croplands. The negative relationship found between clay bound organic matter (CBO) and glucose indicates higher SOM fixation in clay that lower its availability in cultivated lands. In forests, negative relationships between litter and sugars of microbial origin (SMO) showed that litter fuelled microbes to produce sugars. Fucose and glucose increased the availability of Cu, Zn and Mn in forests. Xylose increased Ca availability in cultivated lands. Arabinose, the main carbon source of soil respiration reduced the P availability. This study showed soil carbohydrates and their relationships with mineral nutrients could provide vital information on the availability of limiting nutrients in tropical ecosystems.

  7. Microbial reduction of 99Tc in organic matter-rich soils

    International Nuclear Information System (INIS)

    Abdelouas, A.; Grambow, B.; Fattahi, M.; Andres, Y.; Leclerc-Cessac, E.

    2005-01-01

    For safety assessment purposes, it is necessary to study the mobility of long-lived radionuclides in the geosphere and the biosphere. Within this framework, we studied the behaviour of 99 Tc in biologically active organic matter-rich soils. To simulate the redox conditions in soils, we stimulated the growth of aerobic and facultative denitrifying and anaerobic sulphate-reducing bacteria (SRB). In the presence of either a pure culture of denitrifiers (Pseudomonas aeruginosa) or a consortium of soil denitrifiers, the solubility of TcO 4 - was not affected. The nonsorption of TcO 4 - onto bacteria was confirmed in biosorption experiments with washed cells of P. aeruginosa regardless of the pH. At the end of denitrification with indigenous denitrifiers in soil/water batch experiments, the redox potential (E H ) dropped and this was accompanied by an increase of Fe concentration in solution as a result of reduction of less soluble Fe(III) to Fe(II) from the soil particles. It is suggested that this is due to the growth of a consortium of anaerobic bacteria (e.g., Fe-reducing bacteria). The drop in E H was accompanied by a strong decrease in Tc concentration as a result of Tc(VII) reduction to Tc(IV). Thermodynamic calculations suggested the precipitation of TcO 2 . The stimulation of the growth of indigenous sulphate-reducing bacteria in soil/water systems led to even lower E H with final Tc concentration of 10 -8 M. Experiments with glass columns filled with soil reproduced the results obtained with batch cultures. Sequential chemical extraction of precipitated Tc in soils showed that this radionuclide is strongly immobilised within soil particles under anaerobic conditions. More than 90% of Tc is released together with organic matter (60-66%) and Fe-oxyhydroxides (23-31%). The present work shows that ubiquitous indigenous anaerobic bacteria in soils play a major role in Tc immobilisation. In addition, organic matter plays a key role in the stability of the reduced Tc

  8. Algological and Mycological Characterization of Soils under Pine and Birch Forests in the Pasvik Reserve

    Science.gov (United States)

    Korneikova, M. V.; Redkina, V. V.; Shalygina, R. R.

    2018-02-01

    The structure of algological and mycological complexes in Al-Fe-humus podzols (Albic Podzols) under pine and birch forests of the Pasvik Reserve is characterized. The number of micromycetes is higher in more acid soils of the pine forest, while the species diversity is greater under the birch forest. The genus Penicillium includes the largest number of species. The greatest abundance and occurrence frequency are typical for Penicillium spinulosum, P. glabrum, and Trichoderma viride in pine forest and for Umbelopsis isabellina, Mucor sp., Mortierella alpina, P. glabrum, Aspergillus ustus, Trichoderma viride, and T. koningii in birch forest. Cyanobacteria-algal cenoses of the investigated soils are predominated by green algae. Soils under birch forest are distinguished by a greater diversity of algal groups due to the presence of diatoms and xanthophytes. Species of frequent occurrence are represented by Pseudococcomyxa simplex and Parietochloris alveolaris in soils of the pine forest and by Tetracystis cf. aplanospora, Halochlorella rubescens, Pseudococcomyxa simplex, Fottea stichococcoides, Klebsormidium flaccidum, Hantzschia amphioxys, Microcoleus vaginatus, and Aphanocapsa sp. in soils under birch forest

  9. State of mid-atlantic region forests in 2000

    Science.gov (United States)

    Kenneth W. Stolte; Barbara L. Conkling; Stephanie Fulton; M. Patricia Bradley

    2012-01-01

    Wet and warm climate, mountainous topography, and deep rich soils produced one of the most magnificent and diverse temperate forests in the world. In 1650 the Mid-Atlantic forests covered 95 percent of the region, but were greatly reduced in 1900 by extensive tree harvesting, and conversion to farms and pastures. Settlement of forests also led to severe wildfires, soil...

  10. Effect of N and P addition on soil organic C potential mineralization in forest soils in South China

    Institute of Scientific and Technical Information of China (English)

    OUYANG Xuejun; ZHOU Guoyi; HUANG Zhongliang; ZHOU Cunyu; LI Jiong; SHI Junhui; ZHANG Deqiang

    2008-01-01

    Atmospheric nitrogen deposition is at a high level in some forests of South China. The effects of addition of exogenous N and P on soil organic carbon mineralization were studied to address: (1) if the atmospheric N deposition promotes soil C storage through decreasing mineralization; (2) if the soil available P is a limitation to organic carbon mineralization. Soils (0-10 cm) was sampled from monsoon evergreen broad-leaved forest (MEBF), coniferous and broad-leaved mixed forest (CBMF), and Pinus massoniana forest (PMF) in Dinghushan Biosphere Reserve (located in Gnangdong Province, China). The soils were incubated at 25℃ for 45 weeks, with addition of N (NH4NO3 solution) or P (KH2PO4 solution). CO2-C emission and the inorganic N (NH4+-N and NO3--N) of the soils were determined during the incubation. The results showed that CO2-C emission decreased with the N addition. The addition of P led to a short-term sharp increase in CO2 emission after P application, and the responses of CO2-C evolution to P addition in the later period of incubation related to forest types. Strong P inhibition to CO2 emission occurred in both PMF and CBMF soils in the later incubation. The two-pool kinetic model was fitted well to the data for C turnover in this experiment. The model analysis demonstrated that the addition of N and P changed the distribution of soil organic C between the labile and recalcitrant pool, as well as their mineralization rates. In our experiment, soil pH can not completely explain the negative effect of N addition on CO2-C emission. The changes of soil inorganic N during incubation seemed to support the hypothesis that the polymerization of added nitrogen with soil organic compound by abiotic reactions during incubation made the added nitrogen retard the soil organic carbon mineralization. We conclude that atmospheric N deposition contributes to soil C accretion in the three subtropical forest ecosystems, however, the shortage of soil available P in CBMF and

  11. Microbial community composition and functions are resilient to metal pollution along two forest soil gradients.

    Science.gov (United States)

    Azarbad, Hamed; Niklińska, Maria; Laskowski, Ryszard; van Straalen, Nico M; van Gestel, Cornelis A M; Zhou, Jizhong; He, Zhili; Wen, Chongqing; Röling, Wilfred F M

    2015-01-01

    Despite the global importance of forests, it is virtually unknown how their soil microbial communities adapt at the phylogenetic and functional level to long-term metal pollution. Studying 12 sites located along two distinct gradients of metal pollution in Southern Poland revealed that functional potential and diversity (assessed using GeoChip 4.2) were highly similar across the gradients despite drastically diverging metal contamination levels. Metal pollution level did, however, significantly impact bacterial community structure (as shown by MiSeq Illumina sequencing of 16S rRNA genes), but not bacterial taxon richness and community composition. Metal pollution caused changes in the relative abundance of specific bacterial taxa, including Acidobacteria, Actinobacteria, Bacteroidetes, Chloroflexi, Firmicutes, Planctomycetes and Proteobacteria. Also, a group of metal-resistance genes showed significant correlations with metal concentrations in soil. Our study showed that microbial communities are resilient to metal pollution; despite differences in community structure, no clear impact of metal pollution levels on overall functional diversity was observed. While screens of phylogenetic marker genes, such as 16S rRNA genes, provide only limited insight into resilience mechanisms, analysis of specific functional genes, e.g. involved in metal resistance, appears to be a more promising strategy. © FEMS 2014. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  12. Negative responses of Collembola in a forest soil (Alptal, Switzerland) under experimentally increased N deposition

    International Nuclear Information System (INIS)

    Xu Guoliang; Schleppi, Patrick; Li Maihe; Fu Shenglei

    2009-01-01

    The response of specific groups of organisms, like Collembola to atmospheric nitrogen (N) deposition is still scarcely known. We investigated the Collembola community in a subalpine forest (Alptal, Switzerland) as subjected for 12 years to an experimentally increased N deposition (+25 on top of ambient 12 kg N ha -1 year -1 ). In the 0-5 cm soil layer, there was a tendency of total Collembola densities to be lower in N-treated than in control plots. The density of Isotomiella minor, the most abundant species, was significantly reduced by the N addition. A tendency of lower Collembola group richness was observed in N-treated plots. The Density-Group index (d DG ) showed a significant reduction of community diversity, but the Shannon-Wiener index (H') was not significantly affected by the N addition. The Collembola community can be considered as a bioindicator of N inputs exceeding the biological needs, namely, soil N saturation. - Collembola community, which was significantly affected by a long-term N addition experiment, can be considered as a bioindicator of N saturation.

  13. Negative responses of Collembola in a forest soil (Alptal, Switzerland) under experimentally increased N deposition

    Energy Technology Data Exchange (ETDEWEB)

    Xu Guoliang, E-mail: xugl@scbg.ac.c [Institute of Ecology, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650 (China); Schleppi, Patrick; Li Maihe [Swiss Federal Institute for Forest, Snow and Landscape Research, CH-8903 Birmensdorf (Switzerland); Fu Shenglei, E-mail: sfu@scib.ac.c [Institute of Ecology, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650 (China)

    2009-07-15

    The response of specific groups of organisms, like Collembola to atmospheric nitrogen (N) deposition is still scarcely known. We investigated the Collembola community in a subalpine forest (Alptal, Switzerland) as subjected for 12 years to an experimentally increased N deposition (+25 on top of ambient 12 kg N ha{sup -1} year{sup -1}). In the 0-5 cm soil layer, there was a tendency of total Collembola densities to be lower in N-treated than in control plots. The density of Isotomiella minor, the most abundant species, was significantly reduced by the N addition. A tendency of lower Collembola group richness was observed in N-treated plots. The Density-Group index (d{sub DG}) showed a significant reduction of community diversity, but the Shannon-Wiener index (H') was not significantly affected by the N addition. The Collembola community can be considered as a bioindicator of N inputs exceeding the biological needs, namely, soil N saturation. - Collembola community, which was significantly affected by a long-term N addition experiment, can be considered as a bioindicator of N saturation.

  14. Complementary models of tree species-soil relationships in old-growth temperate forests

    Science.gov (United States)

    Cross, Alison; Perakis, Steven S.

    2011-01-01

    Ecosystem level studies identify plant soil feed backs as important controls on soil nutrient availability,particularly for nitrogen and phosphorus. Although site and species specific studies of tree species soil relationships are relatively common,comparatively fewer studies consider multiple coexisting speciesin old-growth forests across a range of sites that vary underlying soil fertility. We characterized patterns in forest floor and mineral soil nutrients associated with four common tree species across eight undisturbed old-growth forests in Oregon, USA, and used two complementary conceptual models to assess tree species soil relationships. Plant soil feedbacks that could reinforce sitelevel differences in nutrient availability were assessed using the context dependent relationships model, where by relative species based differences in each soil nutrient divergedorconvergedas nutrient status changed across sites. Tree species soil relationships that did not reflect strong feedbacks were evaluated using a site independent relationships model, where by forest floor and surface mineral soil nutrient tools differed consistently by tree species across sites,without variation in deeper mineral soils. We found that theorganically cycled elements carbon, nitrogen, and phosphorus exhibited context-dependent differences among species in both forest floor and mineral soil, and most of ten followed adivergence model,where by species differences were greatest at high-nutrient sites. These patterns are consistent with the oryemphasizing biotic control of these elements through plant soil feedback mechanisms. Site independent species differences were strongest for pool so if the weather able cations calcium, magnesium, potassium,as well as phosphorus, in mineral soils. Site independent species differences in forest floor nutrients we reattributable too nespecies that displayed significant greater forest floor mass accumulation. Our finding confirmed that site-independent and

  15. Mineral Soil Carbon in Managed Hardwood Forests of the Northeastern US

    Science.gov (United States)

    Vario, C.; Friedland, A.; Hornig, C.

    2013-12-01

    New England is characterized by extensive forest cover and large reservoirs of soil carbon (C). In northern hardwood forests, mineral soil C can account for up to 50% of total ecosystem C. There has been an increasing demand for forests to serve both as a C sink and a renewable energy source, and effective management of the ecosystem C balance relies on accurate modeling of each compartment of the ecosystem. However, the dynamics of soil C storage with respect to forest use are variable and poorly understood, particularly in mineral soils. For example, current regional models assume C pools after forest harvesting do not change, while some studies suggest that belowground mineral soil C pools can be affected by disturbances at the soil surface. We quantified mineral soil C pools in previously clear-cut stands in seven research or protected forests across New York, New Hampshire, Massachusetts, and Vermont. The ages of the sites sampled ranged from recently cleared to those with no disturbance history, with 21 forest stands represented in the study. Within each research forest studied, physical parameters such as soil type, forest type, slope and land-use history (aside from forest harvest) did not vary between the stands of different ages. Soil samples were collected to a depth of 60 cm below the mineral-organic boundary using a gas-powered augur and 9.5-cm diameter drill bit. Samples were collected in 10-cm increments in shallow mineral soil and 15-cm increments from 30-60 cm depth. Carbon, nitrogen (N), pH, texture and soil mineralogy were measured across the regional sites. At Bartlett Experimental Forest (BEF) in New Hampshire, mineral soil biogeochemistry in cut and uncut sites was studied at a finer scale. Measurements included soil temperature to 55 cm depth, carbon compound analyses using Py-GCMS and soil microbial messenger RNA extractions from mineral soil. Finally, we simulated C dynamics after harvesting by building a model in Stella, with a particular

  16. Mercury loss from soils following conversion from forest to pasture in Rondonia, Western Amazon, Brazil

    International Nuclear Information System (INIS)

    Almeida, Marcelo D.; Lacerda, Luiz D.; Bastos, Wanderley R.; Herrmann, Joao Carlos

    2005-01-01

    This work reports on the effect of land use change on Hg distribution in Amazon soils. It provides a comparison among Hg concentrations and distribution along soil profiles under different land use categories; primary tropical forest, slashed forest prior to burning, a 1-year silviculture plot planted after 4 years of forest removal and a 5-year-old pasture plot. Mercury concentrations were highest in deeper (60-80 cm) layers in all four plots. Forest soils showed the highest Hg concentrations, ranging from 128 ng g -1 at the soil surface to 150 ng g -1 at 60-80 cm of depth. Lower concentrations were found in pasture soils, ranging from 69 ng g -1 at the topsoil to 135 ng g -1 at 60-80 cm of depth. Slashed and silviculture soils showed intermediate concentrations. Differences among plots of different soil-use categories decreased with soil depth, being non-significant below 60 cm of depth. Mercury burdens were only statistically significantly different between pasture and forest soils at the topsoil, due to the large variability of concentrations. Consequently, estimated Hg losses were only significant between these two land use categories, and only for the surface layers. Estimated Hg loss due to forest conversion to pasture ranged from 8.5 mg m -2 to 18.5 mg m -2 , for the first 20 cm of the soil profile. Mercury loss was comparable to loss rates estimated for other Amazon sites and seems to be directly related to Hg concentrations present in soils. - Deforestation can be responsible for maintaining high Hg levels in the Amazon environment, through a grasshopper effect of Hg remobilization from the affected soils

  17. Landscape heterogeneity, soil climate, and carbon exchange in a boreal black spruce forest.

    Science.gov (United States)

    Dunn, Allison L; Wofsy, Steven C; v H Bright, Alfram

    2009-03-01

    We measured soil climate and the turbulent fluxes of CO2, H2O, heat, and momentum on short towers (2 m) in a 160-yr-old boreal black spruce forest in Manitoba, Canada. Two distinct land cover types were studied: a Sphagnum-dominated wetland, and a feathermoss (Pleurozium and Hylocomium)-dominated upland, both lying within the footprint of a 30-m tower, which has measured whole-forest carbon exchange since 1994. Peak summertime uptake of CO2, was higher in the wetland than for the forest as a whole due to the influence of deciduous shrubs. Soil respiration rates in the wetland were approximately three times larger than in upland soils, and 30% greater than the mean of the whole forest, reflecting decomposition of soil organic matter. Soil respiration rates in the wetland were regulated by soil temperature, which was in turn influenced by water table depth through effects on soil heat capacity and conductivity. Warmer soil temperatures and deeper water tables favored increased heterotrophic respiration. Wetland drainage was limited by frost during the first half of the growing season, leading to high, perched water tables, cool soil temperatures, and much lower respiration rates than observed later in the growing season. Whole-forest evapotranspiration increased as water tables dropped, suggesting that photosynthesis in this forest was rarely subject to water stress. Our data indicate positive feedback between soil temperature, seasonal thawing, heterotrophic respiration, and evapotranspiration. As a result, climate warming could cause covariant changes in soil temperature and water table depths that may stimulate photosynthesis and strongly promote efflux of CO2 from peat soils in boreal wetlands.

  18. Tree species and soil nutrient profiles in old-growth forests of the Oregon Coast Range

    Science.gov (United States)

    Cross, Alison; Perakis, Steven S.

    2011-01-01

    Old-growth forests of the Pacific Northwest provide a unique opportunity to examine tree species – soil relationships in ecosystems that have developed without significant human disturbance. We characterized foliage, forest floor, and mineral soil nutrients associated with four canopy tree species (Douglas-fir (Pseudotsuga menziesii (Mirbel) Franco), western hemlock (Tsuga heterophylla (Raf.) Sarg.), western redcedar (Thuja plicata Donn ex D. Don), and bigleaf maple (Acer macrophyllum Pursh)) in eight old-growth forests of the Oregon Coast Range. The greatest forest floor accumulations of C, N, P, Ca, Mg, and K occurred under Douglas-fir, primarily due to greater forest floor mass. In mineral soil, western hemlock exhibited significantly lower Ca concentration and sum of cations (Ca + Mg + K) than bigleaf maple, with intermediate values for Douglas-fir and western redcedar. Bigleaf maple explained most species-based differences in foliar nutrients, displaying high concentrations of N, P, Ca, Mg, and K. Foliar P and N:P variations largely reflected soil P variation across sites. The four tree species that we examined exhibited a number of individualistic effects on soil nutrient levels that contribute to biogeochemical heterogeneity in these ecosystems. Where fire suppression and long-term succession favor dominance by highly shade-tolerant western hemlock, our results suggest a potential for declines in both soil Ca availability and soil biogeochemical heterogeneity in old-growth forests.

  19. Soil macroinvertebrate communities across a productivity gradient in deciduous forests of eastern North America

    Science.gov (United States)

    Evelyn S. Wenk; Mac A. Callaham; Joseph O' Brien; Paul J. Hanson

    2016-01-01

    Within the temperate, deciduous forests of the eastern US, diverse soil-fauna communities are structured by a combination of environmental gradients and interactions with other biota. The introduction of non-native soil taxa has altered communities and soil processes, and adds another degree of variability to these systems. We sampled soil macroinvertebrate abundance...

  20. Soil respiration patterns and rates at three Taiwanese forest plantations: dependence on elevation, temperature, precipitation, and litterfall

    OpenAIRE

    Huang, Yu-Hsuan; Hung, Chih-Yu; Lin, I-Rhy; Kume, Tomonori; Menyailo, Oleg V.; Cheng, Chih-Hsin

    2017-01-01

    Background Soil respiration contributes to a large quantity of carbon emissions in the forest ecosystem. In this study, the soil respiration rates at three Taiwanese forest plantations (two lowland and one mid-elevation) were investigated. We aimed to determine how soil respiration varies between lowland and mid-elevation forest plantations and identify the relative importance of biotic and abiotic factors affecting soil respiration. Results The results showed that the temporal patterns of so...

  1. Response of coniferous forest ecosystems on mineral soils to nutrient additions: A review of Swedish experiences

    International Nuclear Information System (INIS)

    Nohrstedt, H.Oe.

    2001-01-01

    Nitrogen (N) is the only nutrient that promotes forest growth when given individually. An extra stem growth of 15 m 3 /ha is obtained during a 10 yr period following an application of 150 kg N/ha. Larger growth increases have often been the result of more intensive N fertilization. Lime or wood ash give a minor growth stimulation on sites with a carbon (C) to N ratio below 30 in the humus layer, while the opposite effect prevails on N-poor sites. Nutrients given as soluble fertilizers are readily taken up by trees. Boron deficiency may be induced in northern Sweden after N fertilization or liming. The ground vegetation may be altered by single-shot N fertilization, but long-term effects occur only for intensive regimes. Lime or wood ash may modify the flora if soil pH is significantly altered: the change will be in response to N availability. Fruit-body production of mycorrhizal fungi is disfavoured by chronic N input, but also by lime or ash. However, the mycorrhizal structures on root tips are less affected. Faunistic studies are not common and those present are mostly devoted to soil fauna. A practical N dose of 150 kg N/ha has no clear effect, but higher doses may reduce the abundance in some groups. Hardened wood ash does not significantly affect the soil fauna. Lime favours snails and earthworms, while other groups are often disfavoured. The response of aquatic fauna to terrestrial treatments has hardly been studied. N fertilization generally results in insignificant effects on fish and benthic fauna. Lime and wood ash reduce the acidity of the topsoil, but practical doses (2-3 t/ha) are too low to raise the alkalinity of runoff unless outflow areas are treated. N fertilizer use in forestry and N-free fertilizers lack effects on acidification. N fertilization may, however, be strongly acidifying if nitrification is induced and followed by nitrate leaching. N fertilization often results in increased long-term C retention in trees and soil, but does not promote

  2. Soil properties and understory herbaceous biomass in forests of three species of Quercus in Northeast Portugal

    Directory of Open Access Journals (Sweden)

    Marina Castro

    2014-12-01

    Full Text Available Aim of study: This paper aims to characterize some soil properties within the first 25 cm of the soil profile and the herbaceous biomass in Quercus forests, and the possible relationships between soil properties and understory standing biomass.Area of study: Three monoespecific Quercus forests (Q. suber L., Q. ilex subsp. rotundifolia Lam. and Q. pyrenaica Willd in NE Portugal.Material and methods: During 1999 and 2000 soil properties (pH-KCl, total soil nitrogen (N, soil organic carbon (SOC, C/N ratio, available phosphorus (P, and available potassium (K and herbaceous biomass production of three forest types: Quercus suber L., Quercus ilex subsp. rotundifolia Lam. and Quercus pyrenaica Willd were studied.Main results: The results showed a different pattern of soil fertility (N, SOC, P, K in Quercus forests in NE of Portugal. The C/N ratio and the herbaceous biomass confirmed this pattern. Research highlights: There is a pattern of Quercus sp. distribution that correlates with different soil characteristics by soil characteristics in NE Portugal. Q. pyrenaica ecosystems were found in more favoured areas (mesic conditions; Q. rotundifolia developed in nutrient-poor soils (oligotrophic conditions; and Q. suber were found in intermediate zones.Keywords: fertility; biomass; C/N ratio; cork oak; holm oak; pyrenean oak.

  3. Copper, zinc, and cadmium in various fractions of soil and fungi in a Swedish forest.

    Science.gov (United States)

    Vinichuk, Mykhailo M

    2013-01-01

    Ectomycorrhizal fungi profoundly affect forest ecosystems through mediating nutrient uptake and maintaining forest food webs. The accumulation of metals in each transfer step from bulk soil to fungal sporocarps is not well known. The accumulation of three metals copper (Cu), zinc (Zn) and cadmium (Cd) in bulk soil, rhizosphere, soil-root interface, fungal mycelium and sporocarps of mycorrhizal fungi in a Swedish forest were compared. Concentrations of all three metals increased in the order: bulk soil soil-root interface (or rhizosphere) soil and sporocarps occurred against a concentration gradient. In fungal mycelium, the concentration of all three metals was about three times higher than in bulk soil, and the concentration in sporocarps was about two times higher than in mycelium. In terms of accumulation, fungi (mycelium and sporocarps) preferred Cd to Zn and Cu. Zinc concentration in sporocarps and to a lesser extent in mycelium depended on the concentration in soil, whereas, the uptake of Cu and Cd by both sporocarps and mycelium did not correlate with metal concentration in soil. Heavy metal accumulation within the fungal mycelium biomass in the top forest soil layer (0-5 cm) might account for ca. 5-9% of the total amount of Cu, 5-11% of Zn, and 16-32% of Cd. As the uptake of zinc and copper by fungi may be balanced, this implied similarities in the uptake mechanism.

  4. Bacteria capable of degrading anthracene, phenanthrene, and fluoranthene as revealed by DNA based stable-isotope probing in a forest soil

    Energy Technology Data Exchange (ETDEWEB)

    Song, Mengke [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Jiang, Longfei [College of Life Sciences, Nanjing Agricultural University, Nanjing 210095 (China); Zhang, Dayi [Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ (United Kingdom); Luo, Chunling, E-mail: clluo@gig.ac.cn [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Wang, Yan [Key Laboratory of Industrial Ecology and Environmental Engineering (MOE), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024 (China); Yu, Zhiqiang [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Yin, Hua [College of Environment and Energy, South China University of Technology, Guangzhou 510006 (China); Zhang, Gan [Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China)

    2016-05-05

    Highlights: • Investigate PAHs degraders in forest carbon-rich soils via DNA-SIP. • Rhodanobacter is identified to metabolite anthracene for the first time. • The first fluoranthene degrader belongs to Acidobacteria. • Different functions of PAHs degraders in forest soils from contaminated soils. - Abstract: Information on microorganisms possessing the ability to metabolize different polycyclic aromatic hydrocarbons (PAHs) in complex environments helps in understanding PAHs behavior in natural environment and developing bioremediation strategies. In the present study, stable-isotope probing (SIP) was applied to investigate degraders of PAHs in a forest soil with the addition of individually {sup 13}C-labeled phenanthrene, anthracene, and fluoranthene. Three distinct phylotypes were identified as the active phenanthrene-, anthracene- and fluoranthene-degrading bacteria. The putative phenanthrene degraders were classified as belonging to the genus Sphingomona. For anthracene, bacteria of the genus Rhodanobacter were the putative degraders, and in the microcosm amended with fluoranthene, the putative degraders were identified as belonging to the phylum Acidobacteria. Our results from DNA-SIP are the first to directly link Rhodanobacter- and Acidobacteria-related bacteria with anthracene and fluoranthene degradation, respectively. The results also illustrate the specificity and diversity of three- and four-ring PAHs degraders in forest soil, contributes to our understanding on natural PAHs biodegradation processes, and also proves the feasibility and practicality of DNA-based SIP for linking functions with identity especially uncultured microorganisms in complex microbial biota.

  5. 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)

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

    Science.gov (United States)

    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

  7. Dynamics of soil organic matter in primary and secondary forest succession on sandy soils in The Netherlands: An application of the ROMUL model

    NARCIS (Netherlands)

    Nadporozhskaya, M.A.; Mohren, G.M.J.; Chertov, O.G.; Komarov, A.S.; Mikhailov, A.V.

    2006-01-01

    We applied the simulation model ROMUL of soil organic matter dynamics in order to analyse and predict forest soil organic matter (SOM) changes following stand growth and also to identify gaps of data and modelling problems. SOM build-up was analysed (a) from bare sand to forest soil during a primary

  8. Trends in soil-vegetation dynamics in burned Mediterranean pine forests: the effects of soil properties

    Science.gov (United States)

    Wittenberg, L.; Malkinson, D.

    2009-04-01

    Fire can impact a variety of soil physical and chemical properties. These changes may result, given the fire severity and the local conditions, in decreased infiltration and increased runoff and erosion rates. Most of these changes are caused by complex interactions among eco-geomorphic processes which affect, in turn, the rehabilitation dynamics of the soil and the regeneration of the burnt vegetation. Following wildfire events in two forests growing on different soil types, we investigated runoff, erosion, nutrient export (specifically nitrogen and phosphorous) and vegetation recovery dynamics. The Biriya forest site, burned during the 2006 summer, is composed of two dominant lithological types: soft chalk and marl which are relatively impermeable. The rocks are usually overlain by relatively thick, up of to 80 cm, grayish-white Rendzina soil, which contains large amounts of dissolved carbonate. These carbonates serve as a limiting factor for vegetation growth. The planted forest in Biriya is comprised of monospecific stands of Pinus spp. and Cupressus spp. The Mt. Carmel area, which was last burned in the 2005 spring, represents a system of varied Mediterranean landscapes, differentiated by lithology, soils and vegetation. Lithology is mainly composed of limestone, dolomite, and chalk. The dominant soil is Brown Rendzina whilst in some locations Grey Rendzina and Terra Rossa can be found. The local vegetation is composed mainly of a complex of pine (Pinus halepensis), oak (Quercus calliprinos), Pistacia lentiscus and associations At each site several 3X3 m monitoring plots were established to collect runoff and sediment. In-plot vegetation changes were monitored by a sequence of aerial photographs captured using a 6 m pole-mounted camera. At the terra-rosa sites (Mt. Carmel) mean runoff coefficients were 2.18% during the first year after the fire and 1.6% in the second. Mean erosion rates also decreased, from 42 gr/m2 to 4 gr/m2. The recovering vegetation was

  9. Isotopic evidence for the formation of unusually humus-rich soils in the Baltic region

    Science.gov (United States)

    Leinweber, Peter; Acksel, Andre; Kühn, Peter

    2017-04-01

    Arable mineral soils in the Pleistocene landscape of Northern Germany usually contain about 4 to 8 kg of organic C (Corg) per m2, most of which is visually recognizable concentrated in the tilled topsoil horizon. Some unusually humus-rich (10 to 20 kg Corg m-2), and deeply (> 70 cm) dark-colored soils in coastal regions with mollic properties have been classified as Chernozems. Their location far away from the middle German and Central European Chernozem regions, absence of steppe vegetation and semi-arid climate conditions make classical pedogenetic theories doubtful. However, non-targeted mass spectrometric analyses of soil organic matter (SOM) composition revealed great similarities with typical Chernozems worldwide (Thiele-Bruhn et al., 2014) and made alternative (e.g. waterlogged) pathways of SOM accumulation unlikely. Subsequent detailed multi-method SOM analyses down the soil profiles revealed relative enrichments in cyclic ("black carbon") and heterocyclic organic compounds in the deeper, bioturbated horizons. These were plausibly explained by the input of combustion residues, likely originating from anthropogenic activities because spots of these soils coincided with archeological artifacts of early settlements (Acksel et al., 2016). However, these finding could not completely explain the genesis of Chernozems in the Baltic region. Therefore, we actually explored isotope analyses (12/13C, 13/14C, 14/15N, 32/34S) to find out the origin of these unusual SOM enrichments and the time period in which it occurred. The results will be compiled to a consistent hypothesis on the formation of these soils in the Baltic and other Northern European regions. References Acksel, A., W. Amelung, P. Kühn, E. Gehrt, T. Regier, P. Leinweber. 2016. Soil organic matter characteristics as indicator of Chernozem genesis in the Baltic Sea region. Geoderma Regional 7, 187-200. Thiele-Bruhn, S., Leinweber P., Eckhardt K.-U., Siem H.K., Blume H.-P. 2014. Identifying Chernozem

  10. Soil microbial diversity, site conditions, shelter forest land, saline water drip-irrigation, drift desert.

    Science.gov (United States)

    Jin, Zhengzhong; Lei, Jiaqiang; Li, Shengyu; Xu, Xinwen

    2013-10-01

    Soil microbes in forest land are crucial to soil development in extreme areas. In this study, methods of conventional culture, PLFA and PCR-DGGE were utilized to analyze soil microbial quantity, fatty acids and microbial DNA segments of soils subjected to different site conditions in the Tarim Desert Highway forest land. The main results were as follows: the soil microbial amount, diversity indexes of fatty acid and DNA segment differed significantly among sites with different conditions (F 84%), followed by actinomycetes and then fungi (<0.05%). Vertical differences in the soil microbial diversity were insignificant at 0-35 cm. Correlation analysis indicated that the forest trees grew better as the soil microbial diversity index increased. Therefore, construction of the Tarim Desert Highway shelter-forest promoted soil biological development; however, for enhancing sand control efficiency and promoting sand development, we should consider the effects of site condition in the construction and regeneration of shelter-forest ecological projects. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Effect of altitude and season on microbial activity, abundance and community structure in Alpine forest soils

    Czech Academy of Sciences Publication Activity Database

    Siles, J. A.; Cajthaml, Tomáš; Minerbi, S.; Margesin, R.

    2016-01-01

    Roč. 92, č. 3 (2016), fiw008 ISSN 0168-6496 Institutional support: RVO:61388971 Keywords : Alpine soil s * forest * altitude Subject RIV: EE - Microbiology, Virology Impact factor: 3.720, year: 2016

  12. Two electrophoreses in different pH buffers to purify forest soil DNA ...

    African Journals Online (AJOL)

    USER

    2010-04-19

    Apr 19, 2010 ... forest soil DNA contaminated with humic substances. Weiguo Hou1,2, Bin Lian1* ... weight, and may be soluble or insoluble in water. Similar ..... changes of turnover ecosystems traced by stable carbon isotopes. Chinese J.

  13. Forest soil erosion prediction as influenced by wildfire and roads

    Science.gov (United States)

    Cao, L.; Brooks, E. S.; Elliot, W.

    2017-12-01

    Following a wildfire, the risk of erosion is greatly increased. Forest road networks may change the underlying topography and alter natural flow paths. Flow accumulation and energy can be redistributed by roads and alter soil erosion processes. A LiDAR (Light Detection and Ranging) DEM makes it possible to quantify road topography, and estimate how roads influence surface runoff and sediment transport in a fire-disturbed watershed. With GIS technology and a soil erosion model, this study was carried out to evaluate the effect of roads on erosion and sediment yield following the Emerald Fire southwest of Lake Tahoe. The GeoWEPP model was used to estimate onsite erosion and offsite sediment delivery from each hillslope polygon and channel segment before and after fire disturbance in part of the burned area. The GeoWEPP flow path method was used to estimate the post-fire erosion rate of each GIS pixel. A 2-m resolution LiDAR DEM was used as the terrain layer. The Emerald Fire greatly increased onsite soil loss and sediment yields within the fire boundary. Following the fire, 78.71% of the burned area had predicted sediment yields greater than 4 Mg/ha/yr, compared to the preburn condition when 65.3% of the study area was estimated to generate a sediment yield less than 0.25 Mg/ha/yr. Roads had a remarkable influence on the flow path simulation and sub-catchments delineation, affecting sediment transport process spatially. Road segments acted as barriers that intercepted overland runoff and reduced downslope flow energy accumulation, therefore reducing onsite soil loss downslope of the road. Roads also changed the boundary of sub-catchment and defined new hydrological units. Road segments can transport sediment from one sub-catchment to another. This in turn leads to the redistribution of sediment and alters sediment yield for some sub-catchments. Culverts and road drain systems are of vital importance in rerouting runoff and sediment. Conservation structures can be

  14. Soil trace gas fluxes along orthogonal precipitation and soil fertility gradients in tropical lowland forests of Panama

    Directory of Open Access Journals (Sweden)

    A. L. Matson

    2017-07-01

    Full Text Available Tropical lowland forest soils are significant sources and sinks of trace gases. In order to model soil trace gas flux for future climate scenarios, it is necessary to be able to predict changes in soil trace gas fluxes along natural gradients of soil fertility and climatic characteristics. We quantified trace gas fluxes in lowland forest soils at five locations in Panama, which encompassed orthogonal precipitation and soil fertility gradients. Soil trace gas fluxes were measured monthly for 1 (NO or 2 (CO2, CH4, N2O years (2010–2012 using vented dynamic (for NO only or static chambers with permanent bases. Across the five sites, annual fluxes ranged from 8.0 to 10.2 Mg CO2-C, −2.0 to −0.3 kg CH4-C, 0.4 to 1.3 kg N2O-N and −0.82 to −0.03 kg NO-N ha−1 yr−1. Soil CO2 emissions did not differ across sites, but they did exhibit clear seasonal differences and a parabolic pattern with soil moisture across sites. All sites were CH4 sinks; within-site fluxes were largely controlled by soil moisture, whereas fluxes across sites were positively correlated with an integrated index of soil fertility. Soil N2O fluxes were low throughout the measurement years, but the highest emissions occurred at a mid-precipitation site with high soil N availability. Net negative NO fluxes at the soil surface occurred at all sites, with the most negative fluxes at the low-precipitation site closest to Panama City; this was likely due to high ambient NO concentrations from anthropogenic sources. Our study highlights the importance of both short-term (climatic and long-term (soil and site characteristics factors in predicting soil trace gas fluxes.

  15. Anoxic conditions drive phosphorus limitation in humid tropical forest soil microorganisms

    Science.gov (United States)

    Gross, A.; Pett-Ridge, J.; Weber, P. K.; Blazewicz, S.; Silver, W. L.

    2017-12-01

    The elemental stoichiometry of carbon (C), nitrogen (N) and phosphorus (P) of soil microorganisms (C:N:P ratios) regulates transfers of energy and nutrients to higher trophic levels. In humid tropical forests that grow on P-depleted soils, the ability of microbes to concentrate P from their surroundings likely plays a critical role in P-retention and ultimately in forest productivity. Models predict that climate change will cause dramatic changes in rainfall patterns in the humid tropics and field studies have shown these changes can affect the redox state of tropical forest soils, influencing soil respiration and biogeochemical cycling. However, the responses of soil microorganisms to changing environmental conditions are not well known. Here, we incubated humid tropical soils under oxic or anoxic conditions with substrates differing in both C:P stoichiometry and lability, to assess how soil microorganisms respond to different redox regimes. We found that under oxic conditions, microbial C:P ratios were similar to the global optimal ratio (55:1), indicating most microbial cells can adapt to persistent aerated conditions in these soils. However, under anoxic conditions, the ability of soil microbes to acquire soil P declined and their C:P ratios shifted away from the optimal ratio. NanoSIMS elemental imaging of single cells extracted from soil revealed that under anoxic conditions, C:P ratios were above the microbial optimal value in 83% of the cells, in comparison to 41% under oxic conditions. These data suggest microbial growth efficiency switched from being energy limited under oxic conditions to P-limited under anoxic conditions, indicating that, microbial growth in low P humid tropical forests soils may be most constrained by P-limitation when conditions are oxygen-limited. We suggest that differential microbial responses to soil redox states could have important implications for productivity of humid tropical forests under future climate scenarios.

  16. Recovery of Soil Microbial Community Structure in a Wildfire Impacted Forest Soil

    Science.gov (United States)

    Tate, Robert, III; Mikita, Robyn

    2010-05-01

    Wildfires are common disturbances that will increase in frequency and intensity as a result of conditions associated with the changing climate. In turn, forest fires exacerbate climate conditions by increasing carbon and atmospheric aerosols, and changing the surface albedo. Fires have significant economic, environmental, and ecological repercussions; however, we have a limited understanding on the effect of severe wildfires on the composition, diversity, and function of belowground microorganisms. The objective of this research was to examine the shift of the forest soil microbial community as a result of a severe wildfire in the New Jersey Pinelands. Over the span of two years following the fire, soil samples from the organic and mineral layers of the severely burned sites were collected six times. Samples were also collected twice from an unburned control site. It was hypothesized that soil microbial communities from severely burned samples collected shortly after the fire would be significantly different from (1) the unburned samples that serve as controls and (2) the severely burned samples collected more than a year after the fire. Microbial community composition was analyzed by principal component analysis and multivariate analysis of variance of molecular fingerprint data from denaturing gradient gel electrophoresis of bacterial and archaeal-specific amplicons. Bacterial community composition was significantly different among all the organic and mineral layer samples collected 2, 5, 13, and 17 months following the fire. This indicated a shift in the bacterial communities with time following the fire. Common phylotypes from the burned organic layer samples collected 2 months after the fire related closely to members of the phyla Cyanobacteria and Acidobacteria, whereas those from later samples (5, 13, and 17 months following the fire) were closely related to members of the genus Mycobacteria. Canonical correlation analysis was used to determine connections

  17. An examination of the spatial variability of CO2 in the profile of managed forest soils

    International Nuclear Information System (INIS)

    Black, M.; Kellman, L.; Beltrami, H.

    2005-01-01

    Soil carbon dioxide (CO 2 ) profiles are typically used in soil-gas exchange studies. Although surface flux measuring methods may be more efficient for deriving surface soil CO 2 exchange budgets, they do not provide enough information about the generation of gas through depth. This poses a challenge in quantifying the CO 2 generated from different zones and soil carbon pools through time. The combination of subsurface concentration profiles and estimates of soil diffusivity reveal where CO 2 is being generated in the soil. This combined approach offers greater awareness into processes controlling CO 2 production in soils through depth, and clarifies how soil CO 2 exchange processes in these ecosystems can be changed by management regimes and climate change. Although information about spatial variability in subsurface concentrations within forested soils is limited, it is assumed to be high because of the high spatial variability in soil CO 2 flux estimates and the large variation in vegetation distribution and topography within sites. In this study, the soil CO 2 profile was monitored during the fall of 2004 at depths of 0, 5, 20 and 35 cm at 10 microsites of a clear-cut and an 80 year old intact mixed forest in Atlantic Canada. Microsites were about 10 meters apart and represented a range of microtopographical conditions that typically encompass extremes in soil CO 2 profile patterns. Preliminary results reveal predictable patterns in concentration profiles through depth, and increasing CO 2 concentration with depth, consistent with a large soil source of CO 2 . The significant variability in the soil carbon profile between microsites in the clear-cut and intact forest sites will be investigated to determine if distinct microsite patterns can be identified. The feasibility of using this method for providing process-based versus soil C exchange budgeting information at forested sites will also be examined

  18. 12 years of irrigation in a drought stressed pine forest speeds up carbon cycling and alters the soil biome but has negligible effects on soil organic matter storage

    Science.gov (United States)

    Hagedorn, Frank; Hartmann, Martin; Brunner, Ivano; Rigling, Andreas; Herzog, Claude; Schaub, Marcus; Frey, Beat

    2017-04-01

    Inneralpine valleys are experiencing repeated summer droughts, which have caused a die-back of pine forests since the 1990s. Drought limits the metabolic activity and hence C cycling in the plant and soil system. The net effects of drought on soil organic matter (SOM) storage is, however, ambiguous as drought affects both C inputs and outputs. Moreover, in the long-term, water limitation is also altering above- and belowground diversity due to species-dependent resistance and adaptation to drought. In our study, we explored how ten years of irrigation of a water-limited pine forest in the central European Alps altered above- and belowground diversity and C cycling in the plant and soil systems. The decadal long irrigation during summer time strongly increased ecosystem productivity with litter fall and fine root biomass being increased by +50 and +40%, respectively. At the same time, soil CO2 efflux was stimulated by 60%, indicating that the removal of water limitation enhanced both the inputs and outputs of C into soils. The accelerated C cycling was also mirrored by compositional shifts in the soil microbiome. 454-pyrosequencing of ribosomal marker genes indicated that irrigation promoted bacteria and fungi with more copiotrophic life style strategies, that are typical for nutrient-rich conditions associated with a higher decomposition. Determination of SOM pools revealed a C loss in the organic layer under irrigation (-900 gC m-2) but a C gain in the mineral soil (+970 gC m-2), resulting in a negligible net effect. The likely mechanisms for the altered vertical SOM distribution might be (1) an accelerated mineralization of litter in conjunction with higher C inputs from the rhizosphere and/or (2) an increased incorporation of litter in the mineral soil as suggested by a litter bag experiment showing a stimulated activity of the macrofauna with a 5-fold increase of the earthworm density. In summary, our long-term irrigation experiment revealed that the removal of

  19. Methane production potential and microbial community structure for different forest soils

    Science.gov (United States)

    Matsumoto, Y.; Ueyama, M.; Kominami, Y.; Endo, R.; Tokumoto, H.; Hirano, T.; Takagi, K.; Takahashi, Y.; Iwata, H.; Harazono, Y.

    2017-12-01

    Forest soils are often considered as a methane (CH4) sink, but anaerobic microsites potentially decrease the sink at the ecosystem scale. In this study, we measured biological CH4 production potential of soils at various ecosystems, including upland forests, a lowland forest, and a bog, and analyzed microbial community structure using 16S ribosomal RNA (rRNA) genes. Three different types of soil samples (upland, bank of the stream, and center of the stream) were collected from Yamashiro forest meteorology research site (YMS) at Kyoto, Japan, on 11 May 2017. The soils were incubated at dark and anaerobic conditions under three different temperatures (37°C, 25°C, and 10°C) from 9 June 2017. The upland soils emitted CH4 with largest yields among the three soils at 37°C and 25°C, although no CH4 emission was observed at 10°C. For all temperature ranges, the emission started to increase with a 14- to 20-days lag after the start of the incubation. The lag indicates a slow transition to anaerobic conditions; as dissolved oxygen in water decreased, the number and/or activity of anaerobic bacteria like methanogens increased. The soils at the bank and center of the stream emitted CH4 with smaller yields than the upland soils in the three temperature ranges. The microbial community analyses indicate that methanogenic archaea presented at the three soils including the aerobic upland soil, but compositions of methanogenic archaea were different among the soils. In upland soils, hydrogenotrophic methanogens, such as Methanobacterium and Methanothermobacter, consisted almost all of the total methanogen detected. In the bank and center of the stream, soils contained approximately 10-25% of acetoclastic methanogens, such as Methanosarcina and Methanosaeta, among the total methanogen detected. Methanotrophs, a genus of Methanobacteriaceae, was appeared in the all types of soils. We will present results from same incubation and 16S rRNA analyses for other ecosystems, including

  20. A climate sensitive model of carbon transfer through atmosphere, vegetation and soil in managed forest ecosystems

    Science.gov (United States)

    Loustau, D.; Moreaux, V.; Bosc, A.; Trichet, P.; Kumari, J.; Rabemanantsoa, T.; Balesdent, J.; Jolivet, C.; Medlyn, B. E.; Cavaignac, S.; Nguyen-The, N.

    2012-12-01

    For predicting the future of the forest carbon cycle in forest ecosystems, it is necessary to account for both the climate and management impacts. Climate effects are significant not only at a short time scale but also at the temporal horizon of a forest life cycle e.g. through shift in atmospheric CO2 concentration, temperature and precipitation regimes induced by the enhanced greenhouse effect. Intensification of forest management concerns an increasing fraction of temperate and tropical forests and untouched forests represents only one third of the present forest area. Predicting tools are therefore needed to project climate and management impacts over the forest life cycle and understand the consequence of management on the forest ecosystem carbon cycle. This communication summarizes the structure, main components and properties of a carbon transfer model that describes the processes controlling the carbon cycle of managed forest ecosystems. The model, GO+, links three main components, (i) a module describing the vegetation-atmosphere mass and energy exchanges in 3D, (ii) a plant growth module and a (iii) soil carbon dynamics module in a consistent carbon scheme of transfer from atmosphere back into the atmosphere. It was calibrated and evaluated using observed data collected on coniferous and broadleaved forest stands. The model predicts the soil, water and energy balance of entire rotations of managed stands from the plantation to the final cut and according to a range of management alternatives. It accounts for the main soil and vegetation management operations such as soil preparation, understorey removal, thinnings and clearcutting. Including the available knowledge on the climatic sensitivity of biophysical and biogeochemical processes involved in atmospheric exchanges and carbon cycle of forest ecosystems, GO+ can produce long-term backward or forward simulations of forest carbon and water cycles under a range of climate and management scenarios. This