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Sample records for oak forest soils

  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. Carbon content of forest floor and mineral soil in Mediterranean Pinus spp. and Oak stands in acid soils in Northern Spain

    Energy Technology Data Exchange (ETDEWEB)

    Herrero, C.; Turrión, M.B.; Pando, V.; Bravo, F.

    2016-07-01

    Aim of the study: The aim of the study was to determine the baseline carbon stock in forest floor and mineral soils in pine and oak stands in acid soils in Northern Spain. Area of study: The study area is situated in northern Spain (42° N, 4° W) on “Paramos y Valles” region of Palencia. aterial and methods: An extensive monitoring composed of 48 plots (31 in pine and 17 in oak stands) was carried out. Litter layers and mineral soil samples, at depths of 0-30 cm and 30-60 cm, were taken in each plot. An intensive monitoring was also performed by sampling 12 of these 48 plots selected taken in account species forest composition and their stand development stage. Microbial biomass C (CMB), C mineralization (CRB), and soil organic C balance at stand level were determined in surface soil samples of intensive monitoring. Main results: No differences in soil C content were detected in the two forest ecosystems up to 60 cm depth (53.0±25.8 Mg C ha-1 in Pinus spp. plantations and 60.3±43.8 Mg C ha-1 in oak stands). However, differences in total C (CT), CMB and CRB were found in the upper 10 cm of the soils depending on the stand development stage in each species forest composition (Pinus nigra, Pinus pinaster, Pinus sylvestris and Quercus pyrenaica). Plots with high development stage exhibited significant lower metabolic quotient (qCO2), so, meant more efficient utilization of C by the microbial community. The C content in the forest floor was higher in pine stands (13.7±0.9 Mg C ha-1) than in oak stands (5.4±0.7 Mg C ha-1). A greater turnover time was found in pine ecosystems vs. oak stands. In contrast, forest floor H layer was nonexistent in oak stands. Research highlights: Results about litterfall, forest floor and mineral soil dynamics in this paper can be used strategically to reach environmental goals in new afforestation programs and sustainable forest management approaches. (Author)

  3. 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.

  4. A greenhouse study of northern red oak seedling growth on two forest soils at different stages of acidification

    International Nuclear Information System (INIS)

    Sharpe, W.E.; Swistock, B.R.; Dewalle, D.R.

    1993-01-01

    The objective of this study was to determine whether or not Ca and P in soils from two forested sites at two different stages of acidification were limiting growth of red oak seedlings. The A and E horizons of a Berks soils from Watershed 4 at the Fernow Experimental Forest (cation exchange buffer range) and a Hazelton-Dekalb soil from Pea Vine Hill in Southwestern Pennsylvania (A1 buffer range) were placed in pots and utilized as the growth medium for northern red oak seedlings in a greenhouse environment. Soil water NO 3 -N, Ca, Mg and K concentrations were significantly higher on the Berks soil. Soil exchangeable P and soil solution TP (total phosphorus) were significantly higher on the Hazelton-Dekalb soil. Both soils were amended with bone meal (CaPO 4 ) to determine the effects of Ca and P addition on the growth and nutrient uptake of the seedlings. Height growth of the control red oak seedlings was significantly greater on the Berks soil after 45 d, but amendment of Hazelton-Dekalb soils with bone meal eliminated this difference. Bone meal addition to the Hazelton-Dekalb soil resulted in significantly greater height growth of red oak seedlings when compared to red oak seedings grown on unamended Hazelton-Dekalb soil, but did not have a similar effect for red oak seedlings grown on Berks soil. Bone meal addition to Hazelton-Dekalb soil resulted in greater concentrations of Ca and Mg in red oak leaves. Unfertilized Berks red oak seedling leaves had significantly higher concentrations of Ca and K than their Hazelton-Dekalb counterparts. Al-Ca molar ratios were significantly lower on the Berks soil. Red oak height growth was increased significantly by Ca addition to the Hazelton-Dekalb soil. 24 refs., 2 figs., 8 tabs

  5. The efforts for cork oak forest management and their effects on soil conservation

    Energy Technology Data Exchange (ETDEWEB)

    Laouina, A.; Aderghal, M.; Al Karkouri, J.; Antari, M.; Chaker, M.; Laghazi, Y.; Machmachi, I.; Machouri, N.; Nafaa, R.; Naimi, K.; Nouira, A.; Sfa, M.

    2010-07-01

    The Shoul oak grove is a forested ecosystem inherited from a Holocene phase of ecological optimum; its evolution, through the double geologic and human temporality, and in relation with several processes of degradation, led to the progressive loss of its environmental equilibrium and further to the reduction of its economic contributions. The fragility of these forests is the consequence of the convergence of two main factors, i) the intrinsic fragility of the forested environment based on an unstable balance between the tree, the leached soils and their moisture content ; ii) the anthropological action on the forest environment and its degradation with the change of its floristic composition. During the colonization the new context was at the origin of the new social and economic relation between the forest and the surrounding populations. The current use of this oak grove is in a classic scheme of the reports society / forest in Morocco. The population is especially of pastoral main activity in the bordering communes. But the oak groves of Mamora-Sehoul are integrated into the area of influence of several cities, what exposes the forest to the risks of uncontrolled urbanization. These oak groves are thus in the centre of interest of several stake holders with opposite behaviour and a new paradigm of relation rural/urban. Through a double approach, environmental and socio-economic, this paper will try to bring elements of answer by analyzing the interactions between a forest which reached an alarming threshold of degradation and a society affected by important changes in its modes of intervention and exploitation. (Author) 28 refs.

  6. Comparison of vegetation patterns and soil nutrient relations in an oak-pine forest and a mixed deciduous forest on Long Island, New York

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, S.C.; Curtis, P.S.

    1980-11-01

    An analysis of soil nutrient relations in two forest communities on Long Island, NY, yielded a correlation between the fertility of the top-soil and vegetational composition. The oak-pine forest soils at Brookhaven National Laboratory contain lower average concentrations of NH/sub 3/, Ca, K, and organic matter than the mixed deciduous forest soils in the Stony Brook area. The pH of the topsoil is also more acidic at Brookhaven. The observed differences between localities are greater than within-locality differences between the two soil series tested (Plymouth and Riverhead), which are common to both localities. Nutrient concentrations in the subsoil are not consistently correlated with either locality or soil series, although organic matter and NH/sub 3/ show significantly higher concentrations at Stony Brook. Supporting data on density and basal area of trees and coverage of shrubs and herbs also reveals significant variation between the two forest communities. An ordination of the vegetation data shows higher similarity within than between localities, while no obvious pattern of within-locality variation due to soil series treatments is apparent. These data support the hypothesis that fertility gradients may influence forest community composition and structure. This hypothesis is discussed with reference to vegetation-soil interactions and other factors, such as frequency of burning, which may direct the future development of the Brookhaven oak-pine forest.

  7. Effects of thinning intensities on soil infiltration and water storage capacity in a Chinese pine-oak mixed forest.

    Science.gov (United States)

    Chen, Lili; Yuan, Zhiyou; Shao, Hongbo; Wang, Dexiang; Mu, Xingmin

    2014-01-01

    Thinning is a crucial practice in the forest ecosystem management. The soil infiltration rate and water storage capacity of pine-oak mixed forest under three different thinning intensity treatments (15%, 30%, and 60%) were studied in Qinling Mountains of China. The thinning operations had a significant influence on soil infiltration rate and water storage capacity. The soil infiltration rate and water storage capacity in different thinning treatments followed the order of control (nonthinning): soil infiltration rate and water storage capacity of pine-oak mixed forest in Qinling Mountains. The soil initial infiltration rate, stable infiltration rate, and average infiltration rate in thinning 30% treatment were significantly increased by 21.1%, 104.6%, and 60.9%, compared with the control. The soil maximal water storage capacity and noncapillary water storage capacity in thinning 30% treatment were significantly improved by 20.1% and 34.3% in contrast to the control. The soil infiltration rate and water storage capacity were significantly higher in the surface layer (0~20 cm) than in the deep layers (20~40 cm and 40~60 cm). We found that the soil property was closely related to soil infiltration rate and water storage capacity.

  8. Decomposition of oak leaf litter and millipede faecal pellets in soil under temperate mixed oak forest

    Science.gov (United States)

    Tajovský, Karel; Šimek, Miloslav; Háněl, Ladislav; Šantrůčková, Hana; Frouz, Jan

    2015-04-01

    The millipedes Glomeris hexasticha (Diplopoda, Glomerida) were maintained under laboratory conditions and fed on oak leaf litter collected from a mixed oak forest (Abieto-Quercetum) in South Bohemia, Czech Republic. Every fourth day litter was changed and produced faecal pellets were separated and afterwards analysed. Content of organic carbon and C:N ratio lowered in faecal pellets as compared with consumed litter. Changes in content of chemical elements (P, K, Ca, Mg, Na) were recognised as those characteristic for the first stage of degradation of plant material. Samples of faecal pellets and oak leaf litter were then exposed in mesh bags between the F and H layers of forest soil for up to one year, subsequently harvested and analysed. A higher rate of decomposition of exposed litter than that of faecal pellets was found during the first two weeks. After 1-year exposure, the weight of litter was reduced to 51%, while that of pellets to 58% only, although the observed activity of present biotic components (algae, protozoans, nematodes; CO2 production, nitrogenase activity) in faecal pellets was higher as compared with litter. Different micro-morphological changes were observed in exposed litter and in pellets although these materials originated from the same initial sources. Comparing to intact leaf litter, another structural and functional processes occurred in pellets due to the fragmentation of plant material by millipedes. Both laboratory and field experiments showed that the millipede faecal pellets are not only a focal point of biodegradation activity in upper soil layers, but also confirmed that millipede feces undergo a slower decomposition than original leaf litter.

  9. Effects of Thinning Intensities on Soil Infiltration and Water Storage Capacity in a Chinese Pine-Oak Mixed Forest

    OpenAIRE

    Chen, Lili; Yuan, Zhiyou; Shao, Hongbo; Wang, Dexiang; Mu, Xingmin

    2014-01-01

    Thinning is a crucial practice in the forest ecosystem management. The soil infiltration rate and water storage capacity of pine-oak mixed forest under three different thinning intensity treatments (15%, 30%, and 60%) were studied in Qinling Mountains of China. The thinning operations had a significant influence on soil infiltration rate and water storage capacity. The soil infiltration rate and water storage capacity in different thinning treatments followed the order of control (nonthinning):

  10. The role of selected soil fauna as predators of Apethymus abdominalis Lep. (Hymenoptera: Tenthredinidae) in oak forests in the District Caiuti, Romania

    Science.gov (United States)

    C. Ciornei; N. Popa; L. Ciuca; C. Rang

    2003-01-01

    The present study was initiated in 2001 in the oak forests from Trotus valley (Forest District Caiucti - Bacau, Romania) which were heavily infested by oak sawflies Apethymus abdominalis Lep. (Hymenoptera: Tenthredinidae), in order to understand better the role of soil-inhabitating predators in population regulation of this pest.

  11. Mass loss and nutrient concentrations of buried wood as a function of organic matter removal, soil compaction, and vegetation control in a regenerating oak-pine forest

    Science.gov (United States)

    Felix Ponder; John M. Kabrick; Mary Beth Adams; Deborah S. Page-Dumroese; Marty F. Jurgensen

    2017-01-01

    Mass loss and nutrient concentrations of northern red oak (Quercus rubra) and white oak (Q. alba) wood stakes were measured 30 months after their burial in the upper 10 cm of soil in a regenerating forest after harvesting and soil disturbance. Disturbance treatments were two levels of organic matter (OM) removal (only...

  12. LandscapeDNDC used to model nitrous oxide emissions from soils under an oak forest in southern England

    Science.gov (United States)

    Cade, Shirley; Clemitshaw, Kevin; Lowry, David; Yamulki, Sirwan; Casella, Eric; Molina, Saul; Haas, Edwin; Kiese, Ralf

    2013-04-01

    Nitrous oxide (N2O) is an important greenhouse gas, having a global warming potential of approximately 300 times that of carbon dioxide (CO2), and plays a significant role in depleting stratospheric ozone. Its principal source is microbial activity in soils and waters. Measured values of N2O emissions from soils show high temporal dynamics and a large range as a result of inter-related physico-chemical factors affecting the microbial processes, thus making predictions difficult. Emissions often occur in pulses following re-wetting, frost-thaw or management events such as N-fertilization, which further complicates predictions. Process-based models have been developed to help understand this emission variability and as potential tools for IPCC Tier 3 reporting on national emission inventories. Forests are promoted as sinks for CO2 and can be used as renewable sources of energy or longer term CO2 storage if timber is used in products such as in construction and furniture, provided appropriate replanting takes place. It is important that the effect of any changes in forest management and land use as a result of a desire to reduce CO2 emissions does not increase N2O emissions from forest soils, which are still poorly understood, compared to agricultural soils. LandscapeDNDC (Haas et al 2012) has been developed as a process-oriented model, based on the biogeochemical model, DNDC (Li et al, 1992), in order to simulate biosphere-atmosphere-hydrosphere exchanges at site and regional scales. It can model the carbon and nitrogen turnover and associated greenhouse gas (GHG) emissions of forest, agricultural and grassland ecosystems, and allows modelling of impacts of regional land use change over time. This study uses data (including forest growth, GHG emissions and soil moisture) from an oak forest, known as the Straits Enclosure, at Alice Holt in Hampshire, where extensive measurements have been made by Forest Research since 1995. It involves validation of the site scale

  13. Fire effects on Gambel oak in southwestern ponderosa pine-oak forests

    Science.gov (United States)

    Scott R. Abella; Peter Z. Fulé

    2008-01-01

    Gambel oak (Quercus gambelii) is ecologically and aesthetically valuable in southwestern ponderosa pine (Pinus ponderosa) forests. Fire effects on Gambel oak are important because fire may be used in pine-oak forests to manage oak directly or to accomplish other management objectives. We used published literature to: (1) ascertain...

  14. 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

  15. 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

  16. 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

  17. 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...

  18. Relationships between soil properties and community structure of soil macroinvertebrates in oak-history forests along an acidic deposition gradient

    Energy Technology Data Exchange (ETDEWEB)

    Kuperman, R.G. [Argonne National Lab., IL (United States). Environmental Assessment Div.

    1996-02-01

    Soil macroinvertebrate communities were studied in ecologically analogous oak-hickory forests across a three-state atmospheric pollution gradient in Illinois, Indiana, and Ohio. The goal was to investigate changes in the community structure of soil fauna in study sites receiving different amounts of acidic deposition for several decades and the possible relationships between these changes and physico-chemical properties of soil. The study revealed significant differences in the numbers of soil animals among the three study sites. The sharply differentiated pattern of soil macroinvertebrate fauna seems closely linked to soil chemistry. Significant correlations of the abundance of soil macroinvertebrates with soil parameters suggest that their populations could have been affected by acidic deposition in the region. Abundance of total soil macroinvertebrates decreased with the increased cumulative loading of acidic deposition. Among the groups most sensitive to deposition were: earthworms gastropods, dipteran larvae, termites, and predatory beetles. The results of the study support the hypothesis that chronic long-term acidic deposition could aversely affect the soil decomposer community which could cause lower organic matter turnover rates leading to an increase in soil organic matter content in high deposition sites.

  19. Habitat Fragmentation can Modulate Drought Effects on the Plant-soil-microbial System in Mediterranean Holm Oak (Quercus ilex) Forests.

    Science.gov (United States)

    Flores-Rentería, Dulce; Curiel Yuste, Jorge; Rincón, Ana; Brearley, Francis Q; García-Gil, Juan Carlos; Valladares, Fernando

    2015-05-01

    Ecological transformations derived from habitat fragmentation have led to increased threats to above-ground biodiversity. However, the impacts of forest fragmentation on soils and their microbial communities are not well understood. We examined the effects of contrasting fragment sizes on the structure and functioning of soil microbial communities from holm oak forest patches in two bioclimatically different regions of Spain. We used a microcosm approach to simulate the annual summer drought cycle and first autumn rainfall (rewetting), evaluating the functional response of a plant-soil-microbial system. Forest fragment size had a significant effect on physicochemical characteristics and microbial functioning of soils, although the diversity and structure of microbial communities were not affected. The response of our plant-soil-microbial systems to drought was strongly modulated by the bioclimatic conditions and the fragment size from where the soils were obtained. Decreasing fragment size modulated the effects of drought by improving local environmental conditions with higher water and nutrient availability. However, this modulation was stronger for plant-soil-microbial systems built with soils from the northern region (colder and wetter) than for those built with soils from the southern region (warmer and drier) suggesting that the responsiveness of the soil-plant-microbial system to habitat fragmentation was strongly dependent on both the physicochemical characteristics of soils and the historical adaptation of soil microbial communities to specific bioclimatic conditions. This interaction challenges our understanding of future global change scenarios in Mediterranean ecosystems involving drier conditions and increased frequency of forest fragmentation.

  20. Intensity of 137Cs accumulation by macromycetes of oak-hornbeam forests

    International Nuclear Information System (INIS)

    Orlov, A.A.; Kurbet, T.V.

    2005-01-01

    The intensity of 137 Cs accumulation by fruit bodies of macromycetes of 25 species were studied under conditions of fresh oak forests in oak-hornbeam forests of Podolsk Hills (Ukraine). It was found the intraspecific differences of average values of 137 Cs specific activity in mushrooms fruit bodies on the same forest plots were about 35 times and average values of transfer factor - about 45 times; the ranked row of mushroom species was build up according their average values. It was shown, the row →forest litter saprotrophes→humus sapritrophes→xylotrophes-sapritrophes - is formed according to intensity of 137 Cs accumulation in fruit bodies ecological-trophic groups of macromycete. Permissible levels for density of 137 Cs soil contamination to preserve edible mushrooms were calculated; and it was drawn a conclusion to the effect that studied species of mushrooms can be presented without any limits. (author)

  1. Changes in Soil Carbon and Moisture over the Six Year after Thinning of a Natural Oak Forest

    Science.gov (United States)

    Kim, S.; Han, S. H.; Li, G.; Chang, H.; Kim, H. J.; Son, Y.

    2017-12-01

    The objective of this study was to assess the effects of thinning on soil carbon (C) in a natural oak forest in central Korea. The study forest received three different thinning treatments consisting of un-thinned control (UTC) and two thinning intensities (15% and 30% basal area reductions) in March in 2010. Precipitation near the study forest maintained the normal level from 2010 to 2013 (average 1,400 mm year-1), but abnormally decreased from 2014 to 2016 (average 800 mm year-1). To measure total soil C stock and soil moisture conditions, soils were collected from 0-10, 10-20, and 20-30 cm depths in June, 2010, 2013, and 2016, respectively. Soil microbial biomass C and C-cycling enzymes (β-glucosidase, cellobiohydrolase, β-xylosidase, phenol oxidase, and peroxidase) at 0-10 cm depth were determined in June, 2016. Total soil C stock at 0-30 cm depth increased throughout the study period, whereas soil moisture decreased at all depths from 2013 to 2016. Both thinning treatments had higher total soil C stock at 0-30 cm depth and moisture at 10-20 and 20-30 cm depths than the UTC in 2013 and 2016, whereas the treatments showed no effects in 2010. Microbial biomass C at 0-10 cm depth in 2016 also increased because of the thinning treatments, which was positively correlated to total soil C stock. However, any effects of thinning on C-cycling enzymes were not significant. Our results indicate that thinning could contribute to relieving the impacts of decreasing precipitation by enhancing the storage of soil moisture. Furthermore, the change in total soil C stock under thinning might result from the stimulation of microbial potential for retaining organic C as a form of biomass. This study was supported by the Ministry of Environment (2014001810002) and the National Institute of Forest Science of Korea (FM0101-2009-01).

  2. Contrasting responses to drought of forest floor CO2 efflux in a loblolly pine plantation and a nearby Oak-Hickory forest

    Science.gov (United States)

    S. Palmroth; Chris A. Maier; Heather R. McCarthy; A. C. Oishi; H. S. Kim; Kurt H. Johnsen; Gabrial G. Katul; Ram Oren

    2005-01-01

    Forest floor C02 efflux (Fff) depends on vegetation type, climate, and soil physical properties. We assessed the effects of biological factors on Fff by comparing a maturing pine plantation (PP) and a nearby mature Oak-Hickory-type hardwood forest (HW). Fff was measured...

  3. Phytosociological studies of the forests with sessile oak and Norway spruce from South-Eastern Transylvania

    Directory of Open Access Journals (Sweden)

    Adrian Indreica

    2011-02-01

    Full Text Available The forests with sessile oak (Quercus petraea and Norway spruce (Picea abies from south-eastern Transylvania represent a peculiar type of phytocenoses, rather unusual for the present-day vegetation of Romania’s territory. Aim of the study is to provide a detailed description of the vegetation and to identify the phytosociological and typological units to which it could belong. Beside this, stand structure and regeneration status of the main tree species are illustrated. The studied area is located around Carpathian intermountain depressions Braşov and Ciuc, where vegetation had a peculiar history and today sessile oak forests on high altitude exists, interfering with spruce forests. The hypothesis of the process naturalness is supported by vegetation history in the area, climate, stand structure and peculiarities of herb layer composition (the mixture of relic of both mountain-boreal origin and south-European origin, like Vaccinium vitis-idaea, Pyrola rotundifolia and respectively Potentilla micrantha, Lathyrus venetus respectively. Sintaxonomically, studied phytocenoses with sessile oak and spruce belong mainly to acidophilus oak forests (Luzulo luzuloidis-Quercetum petraeae, but some of them resemble oak-hornbeam forests (Carici pilosae-Carpinetum, indicating a more recent change in stand structure and suggesting that not the soil, but the climate is the driving force of succession. Regeneration of sessile oak is at least satisfactory, but the expansion of spruce in such stands could seriously restrict the survival of sessile oak. A new typological unit will be appropriate,for a better management of sessile oak forests with spruce admixture.

  4. Phytosociological studies of the forests with sessile oak and Norway spruce from South-Eastern Transylvania

    Directory of Open Access Journals (Sweden)

    Adrian Indreica

    2011-06-01

    Full Text Available The forests with sessile oak (Quercus petraea and Norway spruce (Picea abies from south-eastern Transylvania represent a peculiar type of phytocenoses, rather unusual for the present-day vegetation of Romania’s territory. Aim of the study is to provide a detailed description of the vegetation and to identify the phytosociological and typological units to which it could belong. Beside this, stand structure and regeneration status of the main tree species are illustrated. The studied area is located around Carpathian intermountain depressions Brasov and Ciuc, where vegetation had a peculiar history and today sessile oak forests on high altitude exists, interfering with spruce forests. The hypothesis of the process naturalness is supported by vegetation history in the area, climate, stand structure and peculiarities of herb layer composition (the mixture of relic of both mountain-boreal origin and south-European origin, like Vaccinium vitis-idaea, Pyrola rotundifolia and respectively Potentilla micrantha, Lathyrus venetus respectively. Sintaxonomically, studied phytocenoses with sessile oak and spruce belong mainly to acidophilus oak forests (Luzulo luzuloidis-Quercetum petraeae, but some of them resemble oak-hornbeam forests (Carici pilosae-Carpinetum, indicating a more recent change in stand structure and suggesting that not the soil, but the climate is the driving force of succession. Regeneration of sessile oak is at least satisfactory, but the expansion of spruce in such stands could seriously restrict the survival of sessile oak. A new typological unit will be appropriate, for a better management of sessile oak forests with spruce admixture.

  5. Soil respiration shifts as drought-induced tree substitution advances from Scots pine to Holm oak forest

    Science.gov (United States)

    Barba, Josep; Curiel Yuste, Jorge; Poyatos, Rafael; Janssens, Ivan A.; Lloret, Francisco

    2014-05-01

    There is more and more evidences that the current global warming trend and the increase of frequency and intensity of drought events during the last decades in the Northern hemisphere are currently producing an increment of drought-induced forest die-off events, being the Mediterranean region one of the most affected areas. This drought-induced mortality could lead in a vegetation shift with unpredicted consequences in carbon pools, where soils are the most determinant factor in this carbon balance as they contain over two-thirds of carbon on forest ecosystems. There are several uncertainties related on the interaction between soil, environmental conditions and vegetation shifts that could modify their capability to be net carbon sinks or sources in a warming context. We studied soil respiration and its heterotrophic (RH) and autotrophic (Ra) (split in fine roots [Rr] and mycorrhizal respiration [Rs]) components in a mixed Mediterranean forest where Scots pine (Pinus sylvestris L.) are suffering from drought-induced die-off and replaced by Holm oak (Quercus ilex L.) as the dominant tree species. Soil respiration fluxes and its fractions were measured every two weeks during one year at four stages of the substitution process (non defoliated pines [NDP], defoliated pines [DFP], dead pines [DP] and Holm oak [HO]), using the mesh exclusion method. The aims were (i) to describe soil respiration fluxes in a drought-induced secondary successional process, (ii) to test whether the changes in vegetation affected soil respiration fluxes and (iii) to determine the influence of environmental and abiotic variables on the different soil respiration fractions. Total soil respiration was 10.10±6.17 TC ha-1 y-1, RH represented the 67% of the total, Ra represented the 34% of the total, and Rr and Rs were the 22 and 12%, respectively. Significant differences were found in total soil respiration and RH between NDP and HO, being lower in HO than in NDP (34% in total and 48% in RH). No

  6. [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.

  7. Fire Frequency and Vegetation Composition Influence Soil Nitrogen Cycling and Base Cations in an Oak Savanna Ecosystem

    Science.gov (United States)

    McLauchlan, K. K.; Nelson, D. M.; Perakis, S.; Marcotte, A. L.

    2017-12-01

    Fire frequency is crucial for maintaining savannas in the transition between forests and grasslands. In general, increasing fire frequency has two effects: it increases herbaceous plant cover more than woody plant cover, and it lowers soil organic matter stocks. These effects have been demonstrated at a long-term prescribed fire experiment in an oak savanna ecosystem at Cedar Creek Ecosystem Science Reserve, Minnesota, U.S.A. The fire experiment began in 1964 and oak savannas are burned at various frequencies ranging from every year to not at all. This has led to changes in vegetation ranging from almost 100% grassland to 100% oak forest. Additionally, nitrogen stocks almost doubled in the sites that were not burned, as it accumulated in the trees, leaf litter, and soil. We addressed additional soil changes taking place at this experiment by asking the question: How have fire and oak-grass balance affected soil nutrients, specifically nitrogen and base cations? Surface soils were collected from 12 plots on the oak savanna burn experiment. Soils were collected in increments to 100 cm depth, from under grass-dominated vegetation and from under tree-dominated vegetation. We non-destructively estimated soil base cations by measuring elemental concentrations of dried soil subsamples with a handheld x-ray fluorescence analyzer. We also measured carbon and nitrogen concentrations and isotopic composition of the soil samples. Soils in plots with high fire frequency had higher concentrations of calcium than soils in unburned plots (low fire frequency). Similar trends were seen for soil potassium, magnesium, and phosphorus concentrations. In contrast, soils in plots with high fire frequency had dramatically lowered nitrogen cycling rates and stocks across the oak savanna. The contrast between the responses of different nutrients to changing fire frequency has important implications for the consequences of fire and tree-grass composition on nutrient cycling dynamics.

  8. Estimate of biomass and carbon pools in disturbed and undisturbed oak forests in Tunisia

    Energy Technology Data Exchange (ETDEWEB)

    Zribi, L.; Chaar, H.; Khaldi, A.; Henchi, B.; Mouillot, F.; Gharbi, F.

    2016-07-01

    Aim of the study. To estimate biomass and carbon accumulation in a young and disturbed forest (regenerated after a tornado) and an aged cork oak forest (undisturbed forest) as well as its distribution among the different pools (tree, litter and soil). Area of study. The north west of Tunisia. Material and methods. Carbon stocks were evaluated in the above and belowground cork oak trees, the litter and the 150 cm of the soil. Tree biomass was estimated in both young and aged forests using allometric biomass equations developed for wood stem, cork stem, wood branch, cork branch, leaves, roots and total tree biomass based on combinations of diameter at breast height, total height and crown length as independent variables. Main results. Total tree biomass in forests was 240.58 Mg ha-1 in the young forest and 411.30 Mg ha-1 in the aged forest with a low root/shoot ratio (0.41 for young forest and 0.31 for aged forest). Total stored carbon was 419.46 Mg C ha-1 in the young forest and 658.09 Mg C ha-1 in the aged forest. Carbon stock (Mg C ha-1) was estimated to be113.61(27.08%) and 194.08 (29.49%) in trees, 3.55 (0.85%) and 5.73 (0.87%) in litter and 302.30 (72.07%) and 458.27 (69.64%) in soil in the young and aged forests, respectively. Research highlights. Aged undisturbed forest had the largest tree biomass but a lower potential for accumulation of carbon in the future; in contrast, young disturbed forest had both higher growth and carbon storage potential. (Author)

  9. Status of oak seedlings and saplings in the northern United States: implications for sustainability of oak forests

    Science.gov (United States)

    Chris W. Woodall; Randall S. Morin; Jim R. Steinman; Charles H. Perry

    2008-01-01

    Oak species are a substantial component of forest ecosystems in a 24-state region spanning the northern U.S. During recent decades, it has been documented that the health of oak forests has been experiencing large-scale decline. To further evaluate the sustainability of oak forests in nearly half the states of the U.S., the current status of oak seedlings and saplings...

  10. Fire in upper Midwestern oak forest ecosystems: an oak forest restoration and management handbook

    Science.gov (United States)

    Lee E. Frelich; Peter B. Reich; David W. Peterson

    2015-01-01

    We reviewed the literature to synthesize what is known about the use of fire to maintain and restore oak forests, woodlands, and savannas of the upper Midwestern United States, with emphasis on Minnesota, Wisconsin, and Michigan. Included are (1) known physical and ecological effects of fire on oaks from acorn through seedling, established sapling, and mature stages of...

  11. 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.

  12. 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...

  13. Why sustain oak forests?

    Science.gov (United States)

    David Wm. Smith

    2006-01-01

    A brief overview and some personal thoughts are offered that deal with the implications of our social and political systems on the long-term sustainability of our forest resources. The connection of the most recent climatic events, in a geologic-time context, to the development of present day oak dominated forests of the Eastern United States is discussed. The impacts...

  14. Carbon and nitrogen distribution in oak-hickory forests distributed along a productivity gradient

    Energy Technology Data Exchange (ETDEWEB)

    Reber, R.T.; Kaczmarek, D.J.; Pope, P.E.; Rodkey, K.S. [Purdue Univ., West Lafayette, IN (United States)

    1993-12-31

    Biomass, carbon and nitrogen pools were determined for oak-hickory forests of varying productivity. Little information of this type is available for the central hardwood region. Six oak-hickory dominated forests were chosen to represent a range in potential site productivity as influenced by soil type, amount of recyclable nutrients and available water. Biomass, carbon and nitrogen storage were determined for the following components: above ground standing biomass, fine root biomass, forest floor organic layers and litterfall. As site sequestered at each site was dependent more on the amount of living biomass at each site Litterfall, to some extent, increased with increasing site productivity. As potential site productivity decreased, total fine root biomass increased. The data suggest that as site quality decreased fine root production and turnover may become as important in nutrient cycling as annual litterfall.

  15. Assessing management effects on Oak forests in Austria

    Science.gov (United States)

    Gautam, Sishir; Pietsch, Stephan A.; Hasenauer, Hubert

    2010-05-01

    Historic land use as well as silvicultural management practices have changed the structures and species composition of central European forests. Such changes have effects on the growth of forests and contribute to global warming. As insufficient information on historic forest management is available it is hard to explain the effect of management on forests growth and its possible consequences to the environment. In this situation, the BIOME-BGC model, which integrates the main physical, biological and physiological processes based on current understanding of ecophysiology is an option for assessing the management effects through tracking the cycling of energy, water, carbon and nutrients within a given ecosystems. Such models are increasingly employed to simulate current and future forest dynamics. This study first compares observed standing tree volume, carbon and nitrogen content in soil in the high forests and coppice with standards stands of Oak forests in Austria. Biome BGC is then used to assess the effects of management on forest growth and to explain the differences with measured parameters. Close positive correlations and unbiased results and statistically insignificant differences between predicted and observed volumes indicates the application of the model as a diagnostic tool to assess management effects in oak forests. The observed data in 2006 and 2009 was further compared with the results of respective model runs. Further analysis on simulated data shows that thinning leads to an increase in growth efficiency (GE), nitrogen use efficiency (NUE) and water use efficiency (WUE), and to a decrease in the radiation use efficiency (RUE) in both forests. Among all studied growth parameters, only the difference in the NUE was statistically significant. This indicates that the difference in the yield of forests is mainly governed by the NUE difference in stands due to thinning. The coppice with standards system produces an equal amount of net primary

  16. 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.

  17. The biotransformation of soil biocenosis by micromycetes under introduction of Fagus sylvatica L. to oak-hornbeam forest

    Science.gov (United States)

    Likhanov, Artur; Bilyera, Nataliya; Sedykh, Olena; Melnychuk, Maksym

    2017-04-01

    Keywords: micromycetes, beech, soil enzymes, illuminance, Penicillium canescens. European beech (Fagus sylvatica L.) is a commercially valuable tree species. As the potential distribution area for beech forest is restricted by Europe, planting of artificial stands is adopted in this region. Beech introduction can alter ecosystem considerably, but the mechanism of this transformation is not clear. We aimed to define abiotic and biotic parameters affecting floor development in beech stands introduced to the oak-hornbeam forest ecosystem ca.50 years ago in Eastern Europe (Ukraine). The daylight illuminace level was similar (2.9-6.5 klx) for both stands. However, grass cover in beech stands did not exceed 0.1-0.5 % even on sites with illuminace level 7.5-8.3 klx. It does not comply with the commonly used suggestion that shading is the main factor causes forest floor absence in the beech stands. We indicated predominantly biotic factors influencing forest floor formation. Thus, particular edaphon represented by micromycetes was able to inhibit plants and microorganisms. We isolated Penicillium canescens strains from soil under beech stands. These fungi utilized beech root exudates and phenol compounds of leaf litter, and produced biologically active substances caused cytostatic and mutagenic effects. They also accelerated (in 2-3.2 times) soil β-glucosidase activity, but had no effect on phosphatase. The biomass of fungi varied under cultivation of Penicillium canescens strains on Czapek medium with the addition of aqueous extracts of beech leaf litter. The biomass of micromycetes increased on 10-15 % at plant phenols concentrations up to 1 mg mL-1. On the contrary, increasing the concentration of phenols up to 4 mg mL-1resulted in a biomass decrease to 40%. The relationship between the concentration of plant phenols and rate of fungal biomass formation indicates that there is probably seasonal regulation of micromycetes activity in the forest biocenosis. The highest

  18. Forecasting the future of coast live oak forests in the face of sudden oak death

    Science.gov (United States)

    Letty B. Brown; Barbara Allen-Diaz

    2006-01-01

    Little is known about the potential short- and long-term impacts of sudden oak death (SOD) on forest structure and composition. This study began in 2002 to evaluate the effects of SOD on coast live oak (Quercus agrifolia) - California bay laurel (Umbellularia californica) forests over a gradient of Phytophthora ramorum...

  19. Estimation of soil respiration using automated chamber systems in an oak (Quercus mongolica) forest at the Nam-San site in Seoul, Korea.

    Science.gov (United States)

    Joo, Seung Jin; Park, Soon-Ung; Park, Moon-Soo; Lee, Chang Seok

    2012-02-01

    Soil respiration (R(soil)) is the largest component of ecosystem respiration produced by the autotrophic and heterotrophic respirations. Its variability on multiple time scales strongly depends on environmental variables such as temperature and moisture. To investigate the temporal variations of R(soil) in a cool-temperate oak (Quercus mongolica) forest at the Nam-San site in Seoul, Korea, continuous measurements of R(soil) using the automated chamber systems, air and soil temperatures and soil moisture are made for the period from April 2010 to March 2011. The observed data indicate that the R(soil) shows a remarkable seasonal variation in accordance with temperatures with high in summer and low in winter. The R(soil) is found to be strongly correlated with soil temperature (T(s)) at the 5cm depth throughout the year. However, the high fluctuation of R(soil) is found to be related with soil moisture content (M(s)) during the forest growing season. The estimated annual Q(10) value using the 1.5m-high air temperature is found to be 2.4 that is comparable with other studies in temperate forest ecosystems. The optimal regression equation of R(soil) with the T(s) at 5cm depth and the M(s) at 15cm depth is found to be R(soil)=124.3 exp (0.097T(s))-55.3 (M(s))(2)+2931.9 (M(s))-38516 for T(s)≥0°C and R(soil)=0 for T(s)soil). The annual total soil respiration estimated by the optimal regression equation is found to be 1264gCm(-2) with a maximum of 685gCm(-2) in the summer season and a minimum of 33gCm(-2) in the winter season. The present study can be implemented for the determination of the carbon balance of a cool-temperate Q. mongolica forest with the provision of photosynthesis. Copyright © 2011 Elsevier B.V. All rights reserved.

  20. 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

  1. Wildfire and forest disease interaction lead to greater loss of soil nutrients and carbon.

    Science.gov (United States)

    Cobb, Richard C; Meentemeyer, Ross K; Rizzo, David M

    2016-09-01

    Fire and forest disease have significant ecological impacts, but the interactions of these two disturbances are rarely studied. We measured soil C, N, Ca, P, and pH in forests of the Big Sur region of California impacted by the exotic pathogen Phytophthora ramorum, cause of sudden oak death, and the 2008 Basin wildfire complex. In Big Sur, overstory tree mortality following P. ramorum invasion has been extensive in redwood and mixed evergreen forests, where the pathogen kills true oaks and tanoak (Notholithocarpus densiflorus). Sampling was conducted across a full-factorial combination of disease/no disease and burned/unburned conditions in both forest types. Forest floor organic matter and associated nutrients were greater in unburned redwood compared to unburned mixed evergreen forests. Post-fire element pools were similar between forest types, but lower in burned-invaded compared to burned-uninvaded plots. We found evidence disease-generated fuels led to increased loss of forest floor C, N, Ca, and P. The same effects were associated with lower %C and higher PO4-P in the mineral soil. Fire-disease interactions were linear functions of pre-fire host mortality which was similar between the forest types. Our analysis suggests that these effects increased forest floor C loss by as much as 24.4 and 21.3 % in redwood and mixed evergreen forests, respectively, with similar maximum losses for the other forest floor elements. Accumulation of sudden oak death generated fuels has potential to increase fire-related loss of soil nutrients at the region-scale of this disease and similar patterns are likely in other forests, where fire and disease overlap.

  2. Forest stand dynamics and sudden oak death: Mortality in mixed-evergreen forests dominated by coast live oak

    Science.gov (United States)

    L.B. Brown; B. Allen-Diaz

    2009-01-01

    Sudden oak death (SOD), caused by the recently discovered non-native invasive pathogen, Phytophthora ramorum, has already killed tens of thousands of native coast live oak and tanoak trees in California. Little is known of potential short and long term impacts of this novel plant–pathogen interaction on forest structure and composition. Coast live...

  3. The status of oak and hickory regeneration in forests of Virginia

    Science.gov (United States)

    Anita K. Rose

    2008-01-01

    Evidence suggests that eastern U.S. forests dominated by oak (Quercus spp.) and hickory (Carya spp.) may be shifting to more maple- (Acer spp.) and mixed-species dominated forests. Data from the U.S. Forest Service Forest Inventory and Analysis program were used to describe the status of oak and hickory...

  4. Facilitating Oak and Hickory Regeneration in Mature Central Hardwood Forests

    Directory of Open Access Journals (Sweden)

    Eric J. Holzmueller

    2014-12-01

    Full Text Available Advanced oak and hickory regeneration is often absent in mature oak-hickory forests in the Central Hardwood Region of the United States. Prescribed fire and thinning, alone and combined, are commonly prescribed silvicultural treatments that are recommended to initiate the regeneration process. This study examined the regeneration response in three mature oak stands following four treatments: (1 thin, (2 burn, (3 thinning and burning, or (4 no treatment (control. Ten years after initial treatment, results indicate that oak and hickory seedlings had greater height and diameter in the thinning and burning treatment compared to the control and that this treatment may help facilitate desirable regeneration in mature oak-hickory forests.

  5. Evaluation of fire severity via analysis of photosynthetic pigments: Oak, eucalyptus and cork oak leaves in a Mediterranean forest.

    Science.gov (United States)

    Soler, M; Úbeda, X

    2018-01-15

    Few studies to date have examined the effect of the high temperatures attained during wildfire events on the pigments present in forest foliage. Here, we seek to analyse the main photosynthetic pigments in the leaves of the oak, cork oak and eucalyptus following a wildfire. We also subject leaves of these last two species to a range of contact temperatures (100-500 °C) in the laboratory using a muffle furnace. The samples were left in the muffle for two hours at 100, 150, 200, 250, 300, 350, 400 and 500 °C, in line with other soil study models (Úbeda et al., 2009; Düdaite et al., 2013). At temperatures above 250 °C, chromatography fails to detect any pigments. A minimal increase in temperature degrades chlorophyll, the process being more rapid in eucalyptus than in cork oak, while it increases pheophytin concentrations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  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. Strong resilience of soil respiration components to drought-induced die-off resulting in forest secondary succession.

    Science.gov (United States)

    Barba, Josep; Curiel Yuste, Jorge; Poyatos, Rafael; Janssens, Ivan A; Lloret, Francisco

    2016-09-01

    How forests cope with drought-induced perturbations and how the dependence of soil respiration on environmental and biological drivers is affected in a warming and drying context are becoming key questions. The aims of this study were to determine whether drought-induced die-off and forest succession were reflected in soil respiration and its components and to determine the influence of climate on the soil respiration components. We used the mesh exclusion method to study seasonal variations in soil respiration (R S) and its components: heterotrophic (R H) and autotrophic (R A) [further split into fine root (R R) and mycorrhizal respiration (R M)] in a mixed Mediterranean forest where Scots pine (Pinus sylvestris L.) is undergoing a drought-induced die-off and is being replaced by holm oak (Quercus ilex L.). Drought-induced pine die-off was not reflected in R S nor in its components, which denotes a high functional resilience of the plant and soil system to pine die-off. However, the succession from Scots pine to holm oak resulted in a reduction of R H and thus in an important decrease of total respiration (R S was 36 % lower in holm oaks than in non-defoliated pines). Furthermore, R S and all its components were strongly regulated by soil water content-and-temperature interaction. Since Scots pine die-off and Quercus species colonization seems to be widely occurring at the driest limit of the Scots pine distribution, the functional resilience of the soil system over die-off and the decrease of R S from Scots pine to holm oak could have direct consequences for the C balance of these ecosystems.

  8. Estimation of Throughfall and Stemflow Bacterial Flux in a Subtropical Oak-Cedar Forest

    Science.gov (United States)

    Bittar, Thais B.; Pound, Preston; Whitetree, Ansley; Moore, L. Dean; Van Stan, John T.

    2018-02-01

    Transport pathways of microbes between ecosystem spheres (atmosphere, phyllosphere, and pedosphere) represent major fluxes in nutrient cycles and have the potential to affect microbially mediated biogeochemical processes. Novel data on bacterial fluxes from the phyllosphere to the pedosphere during rainfall via throughfall (rain dripping from/through the canopy) and stemflow (rain funneled down tree stems) are reported. Bacterial concentrations were quantified using flow cytometry and validated with quantitative polymerase chain reaction assays in rainfall samples from an oak-cedar forest in coastal Georgia (southeastern U.S.). Bacteria concentrations (cells mL-1) and storm-normalized fluxes (cells m-2 h-1, cells m-2 mm-1) were greater for cedar versus oak. Total bacterial flux was 1.5 × 1016 cells ha-1 yr-1. These previously unexamined bacterial fluxes are interpreted in the context of major elemental pools and fluxes in forests and could represent inoculum-level sources of bacteria (if alive), and organic matter and inorganic solute inputs (if lysed) to soils.

  9. Impacts of Potential Oak Forest Change on Breeding Birds in Northwestern Arkansas

    Science.gov (United States)

    Douglas A. James

    2004-01-01

    Birds found on existing census routes in the Ozark region of northwestern Arkansas were used to predict avifaunal changes that could occur in the area due to oak-hickory forest degradation caused by red oak borer beetle infestations. The two census routes used passed through high elevation forests where red oaks thrive the best. Analysis showed that 21 bird species...

  10. Pathways for resilience in Mediterranean cork oak land use systems

    NARCIS (Netherlands)

    Acácio, V.C.; Holmgren, M.

    2014-01-01

    Context Loss of woodlands and degradation of vegetation and soil have been described for all Mediterranean-type ecosystems worldwide. In the Western Iberian Peninsula, overexploitation of evergreen cork oak land use systems has led to soil erosion, failures in oak recruitment, and loss of forests.

  11. The Role of Tree Mortality in Vitality Assessment of Sessile Oak Forests

    Directory of Open Access Journals (Sweden)

    Imre Berki

    2016-12-01

    Full Text Available Background and Purpose: The drought-induced vitality loss of sessile oak (Quercus petraea (Matt. Liebl. has been continuously observed in Hungary for more than three decades. The decrease in stand density as a consequence of drought-induced mortality has not been taken into consideration in most of the monitoring methods. Materials and Methods: Forest stands without any forest intervention during the last 30 years were selected. Quadrats were designated for the analysis in 18 sessile oak stands along a climatic transect in which foliage transparency and stand density were measured. Drought stress was defined by the water balance approach. By combining the foliage transparency and the relative stand density, a new cumulative assessment method of stand level vitality was introduced to get a more realistic picture about the effects of long-term drought (lasting for several decades on the sessile oak forests in South-East Europe. Results: The calculated health status (100% - vital; 0% - dead of the sessile oak stands was between 70-90% in the moist South-West Hungary and below 50% close to its xeric limit. The individual tree-based vitality assessment method gave considerably higher values on 17 out of 18 sites. Conclusions: Forest monitoring should also consider stand level-based tree mortality in oak forests while assessing health condition especially close to its xeric limit. The proposed new method provides a more realistic picture about the effects of climate change on sessile oak stands particularly for forest managers interested in changing in the wood stock of forests.

  12. Mammals of the Oak forest

    International Nuclear Information System (INIS)

    Otalora Ardila, Aida

    2003-01-01

    The high rate of deforestation over the Andean forests has generated a large proportion of fragmented landscapes in the country. The distribution of oak groves in the country was determined based on ecosystem maps. Charala and Encino oak groves patches are the largest ones found at the east Andes and like others, due to the unfair use of these resources, have suffered a fragmentation process. Fifty-five species of mammals included in 10 orders and 14 families were found in these forests. Chiroptera and Rodentia were the most representative groups. Anthropic processes had produced a 68.1% loss of the habitat and constitute the main threat for these forests. The sizes of the patches were evaluated for three mammal species categories. The patches' area are not favorable for large-size species, intermediately to favorable to medium-size species and are favorable for small-size species. It is suggested that patches' area effect over mammal species could relate to the decrease of species richness and of each fragment area. There are good connections between patches (only five isolated), allowing the presence of a greater species diversity. There is also a bleak plateau zone between connected patches increasing their connectivity and offering different habitats and resources for some mammal species

  13. Community organization of tree species along soil gradients in a north-eastern USA forest

    NARCIS (Netherlands)

    Bigalow, S.W.; Canham, C.D.

    2002-01-01

    1 A study was carried out in oak-northern hardwood forest in NW Connecticut USA involving measurements of growth, light and soil environment of saplings of six canopy trees that are strongly associated with particular soil types as adults. The objectives were to determine patterns of growth response

  14. 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...

  15. Seed production differences of the Andean oak Quercus Humboldtii Bonpl. in two Andean forests of the Colombian Eastern Cordillera

    International Nuclear Information System (INIS)

    Gonzalez Melo, Andres; Parrado Rosselli Angela

    2010-01-01

    Knowledge of mechanisms of tree species reproduction under natural situations including fruit and seed production patterns is very important for forest management strategies. Considering the influence of abiotic factors such as soil characteristics, humidity and rainfall on fruiting phenology, we studied fruit production patterns of the Andean oak (Quercus humboldtii: Fagaceae) in two forest sites of the Colombian Eastern Cordillera (Cachalu and Patios Altos), under contrasting environmental conditions. At both sites, we monitored monthly fruit production of 15 trees in Cachalu and 11 in Patios Altos using fruit/seed traps placed under the tree crowns. In each site soil cores were extracted below the litter layer 20 cm depth, and soil characteristics and nutrients were analyzed. In general, trees in Cachalu produced more fruits than in Patios Altos, as well as mean fruit mass (wet and dry weight) was significantly higher in Cachalu. At both sites, oak fruiting peaked from April to May, when the highest rainfall occurs. We found positive correlations between fruit production and rainfall one month prior. High phosphorus (P) and potassium (K) were the main variables for explaining the high production. In contrast, high aluminum (Al) contents explained the low production found in Patios Altos. We discuss the importance of including fruit production for oak management strategies, such as restoration and reforestation programs.

  16. Geoecohydrological mechanisms couple soil and leaf water dynamics and facilitate species coexistence in shallow soils of a tropical semiarid mixed forest.

    Science.gov (United States)

    Rodríguez-Robles, Ulises; Arredondo, J Tulio; Huber-Sannwald, Elisabeth; Vargas, Rodrigo

    2015-07-01

    Trees growing on shallow rocky soils must have exceptional adaptations when underlying weathered bedrock has no deep fractures for water storage. Under semiarid conditions, hydrology of shallow soils is expected to decouple from plant hydrology, as soils dry out as a result of rapid evaporation and competition for water increases between coexisting tree species. Gas exchange and plant-water relations were monitored for 15 months for Pinus cembroides and Quercus potosina tree species in a tropical semiarid forest growing on c. 20-cm-deep soils over impermeable volcanic bedrock. Soil and leaf water potential maintained a relatively constant offset throughout the year in spite of high intra-annual fluctuations reaching up to 5 MPa. Thus, hydrology of shallow soils did not decouple from hydrology of trees even in the driest period. A combination of redistribution mechanisms of water stored in weathered bedrock and hypodermic flow accessible to oak provided the source of water supply to shallow soils, where most of the actively growing roots occurred. This study demonstrates a unique geoecohydrological mechanism that maintains a tightly coupled hydrology between shallow rocky soils and trees, as well as species coexistence in this mixed forest, where oak facilitates water access to pine. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  17. Sapflow-Based Stand Transpiration in a Semiarid Natural Oak Forest on China’s Loess Plateau

    Directory of Open Access Journals (Sweden)

    Mei-Jie Yan

    2016-10-01

    Full Text Available The semi-arid region of China’s Loess Plateau is characterized by fragile ecosystems and a shortage of water resources. The major natural forest type in this region is the secondary forest with the flora dominated by the Liaodong oak (Quercus liaotungensis Koidz.. To understand its transpiration water use in relation to environmental factors, we applied Granier-type thermal dissipation probes to monitor stem sap flows of 21 sample trees, representing different classes of diameter at breast height in a permanent plot. The stem- and stand-scale transpiration values during the 2008–2010 growing seasons were estimated using measurements of sap flux densities and corresponding sapwood areas. The dominant factors affecting stand-scale transpiration varied with time scales. Daily stand transpiration correlated with daily solar radiation and daytime average vapor pressure deficit. Seasonal and interannual changes in stand transpiration were closely related to leaf area index (LAI values. No obvious relationship was observed between monthly stand transpiration and soil moisture or precipitation during the period, probably as a result of both the hysteretic effect of precipitation on transpiration, and changes in LAI throughout the growing season. Stand transpiration during the three growing seasons ranged from 75 to 106 mm, representing low to normal values for the semi-arid forest. The proportion of transpiration by oak trees in the stand was stable ranging from 60% to 66% and corresponded to their basal area proportion of approximately 59%. The results suggest that the natural forest consisting mainly of oak trees is in a formal stage of forest development that maintains a normal magnitude of annual water consumption.

  18. Phenophases alter the soil respiration-temperature relationship in an oak-dominated forest

    Science.gov (United States)

    Jared L. DeForest; Askoo Noormets; Steve G. McNulty; Ge Sun; Gwen Teeney; Jiquan Chen

    2006-01-01

    Soil respiration (SR) represents a major component of forest ecosystem respiration and is influenced seasonally by environmental factors such as temperature, soil moisture, root respiration, and litter fall. Changes in these environmental factors correspond with shifts in plant phenology. In this study, we examined the relationship between canopy phenophases @re-growth...

  19. Carbon and Nitrogen dynamics in forest soils depending on light conditions and tree species

    Science.gov (United States)

    Veselinovic, Bojana; Hager, Herbert

    2013-04-01

    Climate change mitigation actions under the Kyoto Protocol apply among other decreases of CO2-emissions and/or increases of carbon (C) stocks. As soils represent the second biggest C-reservoir on Earth, an exact estimation of the stocks and reliable knowledge on C-dynamics in forest soils is of high importance. Anyhow, here, the accurate GHG-accounting, emission reductions and increase in C stocks is hampered due to lack of reliable data and solid statistical methods for the factors which influence C-sequestration in and its release from these systems. In spite of good progress in the scientific research, these factors are numerous and diverse in their interactions. This work focuses on influence of the economically relevant tree species - Picea abies, Fagus sylvatica and Quercus spp. - and light conditions on forest floor and mineral soil C and N dynamics in forest soils. Spruce monocultures have been widely used management practices in central European forests during the past century. Such stands are in lower altitudes and on heavy and water logged soils unstable and prone to disturbances, especially to windthrows. We hypothesize that windthrow areas loose C & N and that the establishment of the previous nutrient stocks is, if at all, only possible to be reached over the longer periods of time. We research also how the increased OM depletion affects the change of C & N stocks in forest floor vs. mineral soil. Conversion of such secondary spruce monocultures to site adequate beech and oak forests may enable higher stocks allocated predominantly as stable organic carbon and as plant available nitrogen. For this purpose sites at 300-700 m altitude with planosols were chosen in the region of the Northern Alpine Foothills. A false chronosequence approach was used in order to evaluate the impacts of the tree species and change in light conditions on dynamic of C & N in the forest floor and mineral soil, over the period 0-100 (for oak 120 y.) years. The C- and N

  20. 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.

  1. Seasonal soil VOC exchange rates in a Mediterranean holm oak forest and their responses to drought conditions

    Science.gov (United States)

    Asensio, Dolores; Peñuelas, Josep; Ogaya, Romà; Llusià, Joan

    Available information on soil volatile organic compound (VOC) exchange, emissions and uptake, is very scarce. We here describe the amounts and seasonality of soil VOC exchange during a year in a natural Mediterranean holm oak forest growing in Southern Catalonia. We investigated changes in soil VOC dynamics in drought conditions by decreasing the soil moisture to 30% of ambient conditions by artificially excluding rainfall and water runoff, and predicted the response of VOC exchange to the drought forecasted in the Mediterranean region for the next decades by GCM and ecophysiological models. The annual average of the total (detected) soil VOC and total monoterpene exchange rates were 3.2±3.2 and -0.4±0.3 μg m -2 h -1, respectively, in control plots. These values represent 0.003% of the total C emitted by soil at the study site as CO 2 whereas the annual mean of soil monoterpene exchange represents 0.0004% of total C. Total soil VOC exchange rates in control plots showed seasonal variations following changes in soil moisture and phenology. Maximum values were found in spring (17±8 μg m -2 h -1). Although there was no significant global effect of drought treatment on the total soil VOC exchange rates, annual average of total VOC exchange rates in drought plots resulted in an uptake rate (-0.5±1.8 μg m -2 h -1) instead of positive net emission rates. Larger soil VOC and monoterpene exchanges were measured in drought plots than in control plots in summer, which might be mostly attributable to autotrophic (roots) metabolism. The results show that the diversity and magnitude of monoterpene and VOC soil emissions are low compared with plant emissions, that they are driven by soil moisture, that they represent a very small part of the soil-released carbon and that they may be strongly reduced or even reversed into net uptakes by the predicted decreases of soil water availability in the next decades. In all cases, it seems that VOC fluxes in soil might have greater

  2. Regeneration of native California oaks in the forest zone [Abstract

    Science.gov (United States)

    P.M. McDonald

    1999-01-01

    The two native California oaks in the forest zone of California are California black oak (Quercus kelloggii Newb.) and tanoak (Lithocarpus densiflorus [Hook. and Arn.] Rehd.). Both are ancient species with many adaptations to withstand California's Mediterranean climate, but some weaknesses as well. Both sprout vigorously...

  3. Seasonal Pattern of Decomposition and N, P, and C Dynamics in Leaf litter in a Mongolian Oak Forest and a Korean Pine Plantation

    Directory of Open Access Journals (Sweden)

    Jaeeun Sohng

    2014-10-01

    Full Text Available Distinct seasons and diverse tree species characterize temperate deciduous forests in NE Asia, but large areas of deciduous forests have been converted to conifer plantations. This study was conducted to understand the effects of seasons and tree species on leaf litter decomposition in a temperate forest. Using the litterbag method, the decomposition rate and nitrogen, phosphorous, and carbon dynamics of Mongolian oak (Quercus mongolica, Korean pine (Pinus koraiensis, and their mixed leaf litter were compared for 24 months in a Mongolian oak stand, an adjacent Korean pine plantation, and a Mongolian oak—Korean pine mixed stand. The decomposition rates of all the leaf litter types followed a pattern of distinct seasonal changes: most leaf litter decomposition occurred during the summer. Tree species was less influential on the leaf litter decomposition. The decomposition rates among different leaf litter types within the same stand were not significantly different, indicating no mixed litter effect. The immobilization of leaf litter N and P lasted for 14 months. Mongolian oak leaf litter and Korean pine leaf litter showed different N and P contents and dynamics during the decomposition, and soil P2O5 was highest in the Korean pine plantation, suggesting effects of plantation on soil nutrient budget.

  4. Development, succession, and stand dynamics of upland oak forests in the Wisconsin Driftless Area: Implications for oak regeneration and management

    Science.gov (United States)

    Megan L. Buchanan; Kurt F. Kipfmueller; Anthony W. D' Amato

    2017-01-01

    Throughout the deciduous forests of the eastern United States, oak (Quercus) regeneration has declined in stands historically dominated by oak species. In the Wisconsin Driftless Area, the level of decline in oak regeneration is variable and influenced by stand structural development, historical disturbance regime, abiotic site characteristics, and...

  5. Dendrochronological analysis of white oak growth patterns across a topographic moisture gradient in southern Ohio

    Science.gov (United States)

    Alexander K. Anning; Darrin L. Rubino; Elaine K. Sutherland; Brian C. McCarthy

    2013-01-01

    Moisture availability is a key factor that influences white oak (Quercus alba L.) growth and wood production. In unglaciated eastern North America, available soil moisture varies greatly along topographic and edaphic gradients. This study was aimed at determining the effects of soil moisture variability and macroclimate on white oak growth in mixed-oak forests of...

  6. Carbon and nitrogen accumulation in forest floor and surface soil under different geographic origins of Maritime pine (Pinus pinaster Aiton.) plantations

    Energy Technology Data Exchange (ETDEWEB)

    Ozdemir, E.; Oral, H. V.; Akburak, S.; Makineci, E.; Yilmaz, E.

    2013-09-01

    Aim of study: To determine if plantations consisting of different geographic origins of the Maritime pine (Pinus pinaster Aiton.) could have altered C and N stocks in the forest floor and surface soils. Area of study: Forest floor and mineral soil C and N stocks were measured in four adjacent plantations of different geographic origins of Maritime pine (Gironde, Toulon, Corsica and Spain) and adjacent primary native Sessile oak (Quercus petraea L.) at Burunsuz region in Belgrad Forest where is located in the Istanbul province in the Marmara geographical region between 41° 09’-41° 12’ N latitude and 28° 54’-29° 00’ E longitude in Turkey. Material and methods: Plots were compared as common garden experiments without replications. 15 surface soil (0-10 cm) and 15 forest floor samples were taken from each Maritime pine origins and adjacent native Sessile oak forest. C and N contents were determined on LECO Truspec 2000 CN analyzer. The statistical significance of the results was evaluated by one-way Analysis of Variance (ANOVA). Research highlights: Forest floor carbon mass, nitrogen concentration and nitrogen mass of forest floor showed a significant difference among origins. Soil carbon mass and nitrogen mass did not significantly differ among investigated plots. (Author)

  7. Modeling the Effects of Harvest Alternatives on Mitigating Oak Decline in a Central Hardwood Forest Landscape.

    Directory of Open Access Journals (Sweden)

    Wen J Wang

    Full Text Available Oak decline is a process induced by complex interactions of predisposing factors, inciting factors, and contributing factors operating at tree, stand, and landscape scales. It has greatly altered species composition and stand structure in affected areas. Thinning, clearcutting, and group selection are widely adopted harvest alternatives for reducing forest vulnerability to oak decline by removing susceptible species and declining trees. However, the long-term, landscape-scale effects of these different harvest alternatives are not well studied because of the limited availability of experimental data. In this study, we applied a forest landscape model in combination with field studies to evaluate the effects of the three harvest alternatives on mitigating oak decline in a Central Hardwood Forest landscape. Results showed that the potential oak decline in high risk sites decreased strongly in the next five decades irrespective of harvest alternatives. This is because oak decline is a natural process and forest succession (e.g., high tree mortality resulting from intense competition would eventually lead to the decrease in oak decline in this area. However, forest harvesting did play a role in mitigating oak decline and the effectiveness varied among the three harvest alternatives. The group selection and clearcutting alternatives were most effective in mitigating oak decline in the short and medium terms, respectively. The long-term effects of the three harvest alternatives on mitigating oak decline became less discernible as the role of succession increased. The thinning alternative had the highest biomass retention over time, followed by the group selection and clearcutting alternatives. The group selection alternative that balanced treatment effects and retaining biomass was the most viable alternative for managing oak decline. Insights from this study may be useful in developing effective and informed forest harvesting plans for managing oak

  8. Occurrence of Phytophthora plurivora and other Phytophthora species in oak forests of southern Poland and their association with site conditions and the health status of trees.

    Science.gov (United States)

    Jankowiak, R; Stępniewska, H; Bilański, P; Kolařík, M

    2014-11-01

    Phytophthora plurivora and other Phytophthora species are known to be serious pathogens of forest trees. Little is known, however, about the presence of P. plurivora in Polish oak forests and their role in oak decline. The aims of this study were to identify P. plurivora in healthy and declining Quercus robur stands in southern Poland and to demonstrate the relationship between different site factors and the occurrence of P. plurivora. In addition, the virulence of P. plurivora and other Phytophthora species was evaluated through inoculations using 2-year-old oak seedlings. Rhizosphere soil was investigated from 39 oak stands representing different healthy tree statuses. The morphology and DNA sequences of the internal transcribed spacer regions (ITS) of the ribosomal DNA and the mitochondrial cox1 gene were used for identifications. P. plurivora, an oak fine root pathogen, was isolated from rhizosphere soil samples in 6 out of 39 stands. Additionally, Phytophthora cambivora, Phytophthora polonica and Phytophthora rosacearum-like were also obtained from several stands. The results showed a significant association between the presence of P. plurivora and the health status of oak trees. Similar relationships were also observed for all identified Phytophthora species. In addition, there was evidence for a connection between the presence of all identified Phytophthora species and some site conditions. Phytophthora spp. occurred more frequently in declining stands and in silt loam and sandy loam soils with pH ≥ 3.66. P. plurivora and P. cambivora were the only species capable of killing whole plants, producing extensive necrosis on seedling stems.

  9. Change in Soil and Forest Floor Carbon after Shelterwood Harvests in a New England Oak-Hardwood Forest, USA

    Directory of Open Access Journals (Sweden)

    Kayanna L. Warren

    2014-01-01

    Full Text Available There has been effort worldwide to quantify how much carbon forests contain in order to designate appropriate offset credits to forest carbon climate mitigation. Carbon pools on or immediately below the soil surface are understood to be very active in response to environmental change but are not well understood. Our study focused on the effects of shelterwood regeneration harvests in New England on the carbon stored in litter, woody debris, and surface soil carbon. Results demonstrate significant difference in surface (0–10 cm soil carbon between control (nonharvested and harvested sites, with higher carbon percentage on control sites. Results showed a significant difference in coarse woody debris with higher amounts of carbon per area on harvested sites. No significant difference in litter mass was recorded between harvested and control sites. When coarse woody debris and litter are included with soil carbon, total carbon did not have a significant decline over 20 years following shelterwood treatment to the forest to secure regeneration, but there was considerable variability among sites. When taking all surface soil carbon measurements together, our results suggest that for accounting purposes the measurement of below-ground carbon after shelterwood harvests is not necessary for the southern New England region.

  10. Social participation and oak forest conservation: Paipa and Duitama study case

    International Nuclear Information System (INIS)

    Escobar Torres, Vivian Constanza; Palacio Tamayo, Dolly Cristina

    2010-01-01

    Social dynamics within social participation is a crucial issue for the accomplishment of forest conservation. In order to contribute to this field, a study of 31 institutional and community organized actors' cooperative practices, within forest conservation processes in Paipa and Duitama, located at the oak forests conservation corridor Guantiva, La Rusia, Iguaque in Colombia, was made, applying Social Network Analysis (SNA). Particularly, this article inquiry is about models of participation of these actors within the period of 2004-2008, looking at their projects and actions as management practices of forest conservation. The research questions were how social participation is included and understood in the conservation of these oak forests, observing cooperative practices amongst this set of actors, at local level. The results are related with the structural patterns of co-participation established amongst these actors within each other's projects and actions and the impact of those in the aim of forest conservation at local level, regarding power relations and its impact on forest conservation.

  11. Water infiltration and hydraulic conductivity in a natural Mediterranean oak forest: impacts of hydrology-oriented silviculture on soil hydraulic properties

    Science.gov (United States)

    Di Prima, Simone; Bagarello, Vincenzo; Bautista, Inmaculada; Cerdà, Artemi; Cullotta, Sebastiano; del Campo, Antonio; González-Sanchis, María; Iovino, Massimo; Maetzke, Federico

    2016-04-01

    microcontroller platform, Arduino. The very limited cost of the system could represent a step towards a cheaper and more widespread application of accurate and automated infiltration rate measurement. However, automatic data collection increases measurement speed, permits measurement at short time intervals, improves measurement precision, allows for more efficient data handling and analysis, and reduces the amount of effort involved and the potential for errors that may occur when manual procedures are applied (Di Prima et al., 2016). The main objective of this study was to determine soil hydraulic properties by using the combination of the automated infiltrometer and the BEST algorithm in a natural Mediterranean oak forest. The forest is located in a typical Mediterranean area, within the public forest La Hunde, Valencia (NE Spain). Two contiguous plots established in previous studies conducted by González-Sanchis et al. (2015) were selected, one of them was thinned reducing the forest density from 861 to 414 tree per ha. Control plot was not thinned. These authors studied the water cycle during the period 2012-2013. In particular, they characterized and compared the plots in term of throughfall, stemflow, soil moisture and transpiration, concluding that the AFM results in an increasing water availability, and at the same time in a substantial maintenance of overland and surface flow, precluding therefore enhancement of erosion rate. In this paper, the focus was put on the impacts of thinning on soil hydraulic properties, such as infiltration capacity, hydraulic conductivity and soil water retention, determined by simplified and low-cost methods in connection with a hydrology-oriented silviculture. Acknowledgements This study is a part of research projects: "Indagini sperimentali per la simulazione dei processi di formazione del deflusso superficiale nei suoli boscati, Progetto FIRB 2012 - MIMOSE", and "CGL2011-28776-C02-02, HYDROSIL" References Alagna, V., Bagarello, V., Di

  12. Ectomycorrhizal fungal diversity and community structure associated with cork oak in different landscapes.

    Science.gov (United States)

    Reis, Francisca; Valdiviesso, Teresa; Varela, Carolina; Tavares, Rui M; Baptista, Paula; Lino-Neto, Teresa

    2018-05-01

    Cork oak (Quercus suber L.) forests play an important ecological and economic role. Ectomycorrhizal fungi (ECMF) are key components for the sustainability and functioning of these ecosystems. The community structure and composition of ECMF associated with Q. suber in different landscapes of distinct Mediterranean bioclimate regions have not previously been compared. In this work, soil samples from cork oak forests residing in different bioclimates (arid, semi-arid, sub-humid, and humid) were collected and surveyed for ectomycorrhizal (ECM) root tips. A global analysis performed on 3565 ECM root tips revealed that the ECMF community is highly enriched in Russula, Tomentella, and Cenoccocum, which correspond to the ECMF genera that mainly contribute to community differences. The ECMF communities from the rainiest and the driest cork oak forests were distinct, with soils from the rainiest climates being more heterogeneous than those from the driest climates. The analyses of several abiotic factors on the ECMF communities revealed that bioclimate, precipitation, soil texture, and forest management strongly influenced ECMF structure. Shifts in ECMF with different hyphal exploration types were also detected among forests, with precipitation, forest system, and soil texture being the main drivers controlling their composition. Understanding the effects of environmental factors on the structuring of ECM communities could be the first step for promoting the sustainability of this threatened ecosystem.

  13. Different harvest intensity and soil CO2 efflux in sessile oak coppice forests

    Czech Academy of Sciences Publication Activity Database

    Dařenová, Eva; Majtaz, C.; Pavelka, Marian

    2016-01-01

    Roč. 9, feb (2016), s. 546-552 ISSN 1971-7458 R&D Projects: GA MŠk(CZ) LO1415; GA MŠk(CZ) EE2.3.20.0267 Institutional support: RVO:67179843 Keywords : Low Forest * Soil Moisture * Soil Respiration * Temperature Dependence Subject RIV: GK - Forestry Impact factor: 1.623, year: 2016

  14. The Effects of Lime, Fertilizer, and Herbicide on Forest Soil Solution Chemistry and Northern Red Oak Radial Growth Following Shelterwood Harvest

    Science.gov (United States)

    Angela M Happel; William E. Sharpe

    2004-01-01

    Soil acidity, nutrient deficient soils, lack of light penetration, herbivory, and understory competition are the major obstacles encountered in regenerating and sustaining northern red oak. Changes in soils that may occur during soil acidifi- cation include: reduced soil pH, increased availability of aluminum (Al) and manganese (Mn), loss of base cations due to...

  15. Carbon and nitrogen accumulation in forest floor and surface soil under different geographic origins of Maritime pine (Pinus pinaster Aiton. plantations

    Directory of Open Access Journals (Sweden)

    E. Ozdemir

    2013-07-01

    Full Text Available Aim of study : To determine if plantations consisting of different geographic origins of the Maritime pine (Pinus pinaster Aiton. could have altered C and N stocks in the forest floor and surface soils.Area of study : Forest floor and mineral soil C and N stocks were measured in four adjacent plantations of different geographic origins of Maritime pine (Gironde, Toulon, Corsica and Spain and adjacent primary native Sessile oak (Quercus petraea L. at Burunsuz region in Belgrad Forest where is located in the Istanbul province in the Marmara geographical region between 41°09' -41°12' N latitude and 28°54' - 29°00' E longitude in Turkey.Material and Methods : Plots were compared as common garden experiments without replications. 15 surface soil (0-10 cm and 15 forest floor samples were taken from each Maritime pine origins and adjacent native Sessile oak forest. C and N contents were determined on LECO Truspec 2000 CN analyzer. The statistical significance of the results was evaluated by one-way Analysis of Variance (ANOVA.Research highlights : Forest floor carbon mass, nitrogen concentration and nitrogen mass of forest floor showed a significant difference among origins. Soil carbon mass and nitrogen mass did not significantly differ among investigated plots.Keywords: carbon sequestration; C/N ratio; decomposition; exotic; tree provenance.

  16. Responses of oaks and tanoaks to the sudden oak death pathogen after 8 y of monitoring in two coastal California forests

    Science.gov (United States)

    Brice A. McPherson; Sylvia R. Mori; David L. Wood; Maggi Kelly; Andrew J. Storer; Pavel Svihra; Richard B. Standiford

    2010-01-01

    Sudden oak death, caused by Phytophthora ramorum, is widely established in mesic forests of coastal central and northern California. In 2000, we placed 18 plots in two Marin County sites to monitor disease progression in coast live oaks (Quercus agrifolia), California black oaks (Q. kelloggii), and tanoaks (Lithocarpus densiflorus), the species that are most...

  17. Stemflow variation in Mexico's northeastern forest communities: Its contribution to soil moisture content and aquifer recharge

    Science.gov (United States)

    Návar, José

    2011-09-01

    SummaryStemflow hydro-ecological importance was measured in trees and assessed in Mexico's northeast forest stands by answering three basic questions: (a) what are the intra and inter-specific stemflow variations; (b) is the stemflow coefficient constant from tree level to stand scales? and (c) what is the stemflow area and wetted soil volume in individual trees and the stemflow volume discharged at the stand scale in two plant communities of northeastern Mexico? Gross rainfall and stemflow flux measurements were conducted on 78 trees of semi-arid, sub-tropical (31 Diospyros texana; 14 Acacia rigidula; four Bumelia celastrina; five Condalia hookeri; three Cordia bioissieri; three Pithecellobium pallens) and temperate forest communities (six Pinus pseudostrobus Lindl. and 12 Quercus spp.). Stemflow was extrapolated from individual trees to the stand scale using 98 inventory plots (1600 m 2 ha -1 each) placed in oak-pine forests and 37 quadrats (5 m × 5 m each) distributed across the Tamaulipan thornscrub forest range. Stemflow infiltration flux and infiltration area measurements assessed the wetted soil volume. Daily measurements were conducted from May of 1997 to November of 1998. Results showed that stemflow coefficients varied between plant communities since they averaged (confidence intervals, α = 0.05) 2.49% (0.57), 0.30% (0.09), and 0.77% (0.27) of the bulk precipitation for Tamaulipan thornscrub, pine, and oak forests, respectively. Intra-specific stemflow variations could not be identified in Tamaulipan although in temperate tree species. Basal diameter explained intra-specific stemflow variation in both plant communities. Stemflow increased threefold since it accounted for by 6.38% and 2.19% of the total bulk rainfall for Tamaulipan thornscrub quadrats and temperate oak-pine inventory plots, respectively. Small shrubs growing underneath large trees, in combination with the presence of small-diameter trees that recorded the largest stemflow coefficients

  18. Sustaining oak forests in eastern North America: regeneration and recruitment, the pillars of sustainability

    Science.gov (United States)

    Daniel C. Dey

    2014-01-01

    Oak cover types comprise half of the forestlands in the eastern United States. There is a great desire to sustain these highly valued forests. Unfortunately, reports of the successional replacement of oak are all too common, as they are throughout the world. Sustaining the oak resource requires the ability to both regenerate and recruit oak into the overstory as...

  19. Establishing Mixtures of Redcedar In Poor Oak-Hickory Forests

    Science.gov (United States)

    Leon S. Minckler

    1966-01-01

    Oak-history forests on the poorest sites in the Upper Mississippi Valley have both low productivity and little esthetic appeal. A mixture of the native evergreen redcedar would add bearty and increase wildlife values.

  20. Capturing forest dependency in the central Himalayan region: Variations between Oak (Quercus spp.) and Pine (Pinus spp.) dominated forest landscapes.

    Science.gov (United States)

    Chakraborty, Anusheema; Joshi, Pawan Kumar; Sachdeva, Kamna

    2018-05-01

    Our study explores the nexus between forests and local communities through participatory assessments and household surveys in the central Himalayan region. Forest dependency was compared among villages surrounded by oak-dominated forests (n = 8) and pine-dominated forests (n = 9). Both quantitative and qualitative analyses indicate variations in the degree of dependency based on proximity to nearest forest type. Households near oak-dominated forests were more dependent on forests (83.8%) compared to households near pine-dominated forests (69.1%). Forest dependency is mainly subsistence-oriented for meeting basic household requirements. Livestock population, cultivated land per household, and non-usage of alternative fuels are the major explanatory drivers of forest dependency. Our findings can help decision and policy makers to establish nested governance mechanisms encouraging prioritized site-specific conservation options among forest-adjacent households. Additionally, income diversification with respect to alternate livelihood sources, institutional reforms, and infrastructure facilities can reduce forest dependency, thereby, allowing sustainable forest management.

  1. Monitoring oak-hickory forest change during an unprecedented red oak borer outbreak in the Ozark Mountains: 1990 to 2006

    Science.gov (United States)

    Jones, Joshua S.; Tullis, Jason A.; Haavik, Laurel J.; Guldin, James M.; Stephen, Fred M.

    2014-01-01

    Upland oak-hickory forests in Arkansas, Missouri, and Oklahoma experienced oak decline in the late 1990s and early 2000s during an unprecedented outbreak of a native beetle, the red oak borer (ROB), Enaphalodes rufulus (Haldeman). Although remote sensing supports frequent monitoring of continuously changing forests, comparable in situ observations are critical for developing an understanding of past and potential ROB damage in the Ozark Mountains. We categorized forest change using a normalized difference water index (NDWI) applied to multitemporal Landsat TM and ETM+ imagery (1990, 2001, and 2006). Levels of decline or growth were categorized using simple statistical thresholds of change in the NDWI over time. Corresponding decline and growth areas were then observed in situ where tree diameter, age, crown condition, and species composition were measured within variable radius plots. Using a machine learning decision tree classifier, remote sensing-derived decline and growth was characterized in terms of in situ observation. Plots with tree quadratic mean diameter at breast height ≥21.5 cm were categorized remotely as in severe decline. Landsat TM/ETM+-based NDWI derivatives reveal forest decline and regrowth in post-ROB outbreak surveys. Historical and future Landsat-based canopy change detection should be incorporated with existing landscape-based prediction of ROB hazard.

  2. The most significant fungi: Agents of wood decay in oak forests of Serbia

    Directory of Open Access Journals (Sweden)

    Milijašević Tanja

    2007-01-01

    Full Text Available The most widely distributed oak species in Serbia are Q. petrea (sessile oak, Q. cerris (Turkey oak and Q. frainetto (Hungarian oak and Quercus robur (common oak, and lignicolous fungi are the major agents of wood decay in natural and coppice oak forests. In this research, 33 species of fungi were identified. Eleven species were described, among which the most significant are: Armillaria mellea, Fomes fomentarius, Hypoxylon deustum Laetiporus sulphureus, Lenzites quercina and Phellinus robustus. This paper presents the morphological characteristics of the most significant identified fungi, their distribution, host plants and significance.

  3. How Biotic Differentiation of Human Impacted Nutrient Poor Deciduous Forests Can Affect the Preservation Status of Mountain Forest Vegetation

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    Tomasz Durak

    2016-10-01

    Full Text Available A significant loss of biodiversity resulting from human activity has caused biotic homogenisation to become the dominant process shaping forest communities. In this paper, we present a rare case of biotic differentiation in European temperate deciduous forest herb layer vegetation. The process is occurring in nutrient poor oak-hornbeam forests in mountain areas (Polish Eastern Carpathians, Central Europe where non-timber use was converted into conventional forest management practice. This change contributed to increases in the nitrogen content and pH reaction of the soil that, contrary to predominant beliefs on the negative impact of habitat eutrophication on diversity, did not result in a decrease in the latter. We discuss possible reasons for this phenomenon that indicate the important role of tree stand composition (an increasing admixture of beech worsening the trophic properties of the soil. The second issue considered involves the effect of the changes in herb species composition of oak-hornbeam forest on its distinctiveness from the beech forest predominating in the Polish Eastern Carpathians. Unfortunately, despite the increase in the species compositional dissimilarity of oak-hornbeam forest, a reduction in their distinctiveness in relation to the herb species composition of beech forest was found. Such a phenomenon is an effect of the major fragmentation of oak-hornbeam forests, a spread of beech forest-type species, and forest management that gives preference to beech trees. Consequently, it can be expected that changes occurring in oak-hornbeam forest vegetation will contribute to a decrease in the forest vegetation variability at the regional scale.

  4. Predicting oak density with ecological, physical, and soil indicators

    Science.gov (United States)

    Callie Jo Schweitzer; Adrian A. Lesak; Yong Wang

    2006-01-01

    We predicted density of oak species in the mid-Cumberland Plateau region of northeastern Alabama on the basis of basal area of tree associations based on light tolerances, physical site characteristics, and soil type. Tree basal area was determined for four species groups: oaks (Quercus spp.), hickories (Carya spp.), yellow-poplar...

  5. Lignin properties in topsoils of a beech/oak forest after 8 years of manipulated litter fall: relevance of altered input and oxidation of lignin

    NARCIS (Netherlands)

    Klotzbücher, T.; Strohmeier, S.; Kaiser, K.; Bowden, R.D.; Lajtha, K.; Ohm, H.; Kalbitz, K.

    2013-01-01

    Background and aims We studied the response of lignin oxidation in soils of a beech/oak forest to changes in litter fall. Additionally we considered possible factors in lignin oxidation, including altered (i) input of fresh organic matter and (ii) fungi-to-bacteria ratios. Methods The field-based

  6. Urbanization effects on soil nitrogen transformations and microbial biomass in the subtropics

    Science.gov (United States)

    Heather A. Enloe; B. Graeme Lockaby; Wayne C. Zipperer; Greg L. Somers

    2015-01-01

    As urbanization can involve multiple alterations to the soil environment, it is uncertain how urbanization effects soil nitrogen cycling. We established 22–0.04 ha plots in six different land cover types—rural slash pine (Pinus elliottii) plantations (n=3), rural natural pine forests (n=3), rural natural oak forests (n=4), urban pine forests (n=3), urban oak forests (n...

  7. Stand Structure, Productivity and Carbon Sequestration Potential of Oak Dominated Forests in Kumaun Himalaya

    OpenAIRE

    Bijendra Lal; L.S. Lodhiyal

    2016-01-01

    Present study deals with stand structure, biomass, productivity and carbon sequestration in oak dominated forests mixed with other broad leaved tree species. The sites of studied forests were located in Nainital region between 29058’ N lat. and 79028’ E long at 1500-2150 m elevation. Tree density of forests ranged from 980-1100 ind.ha-1. Of this, oak trees shared 69-97%. The basal area of trees was 31.81 to 63.93 m2 ha-1. R. arboreum and Q. floribunda shared maximum basal area 16.45 and 16.32...

  8. Monitoring endophyte populations in pine plantations and native oak forests in Northern Spain

    Energy Technology Data Exchange (ETDEWEB)

    Martinez-Alvarez, P.; Martin-Garcia, J.; Rodriguez-Ceinos, S.; Diez, J. J.

    2012-07-01

    The replacement of native forest with plantations of other species may have important impacts on ecosystems. Some of these impacts have been widely studied, but very little is known about the effects on fungal communities and specifically endo phytic fungi. In this study, endophyte assemblages in pine plantations (Pinus sylvestris, P. nigra and P. pinaster) and native oak forests (Quercus pyrenaica) in the north of the province of Palencia (Spain) were analyzed. For this purpose, samples of needles/leaves and twigs were collected from three trees in each of three plots sampled per host species. The samples were later processed in the laboratory to identify all of the endo phytic species present. In addition, an exhaustive survey was carried out of the twelve sites to collect data on the environmental, crown condition, dendrometric and soil variables that may affect the distribution of the fungi. The endophyte assemblages isolated from P. sylvestris and P. nigra were closely related to each other, but were different from those isolated from P. pinaster. The endophytes isolated from Q. pyrenaica were less closely related to those from the other hosts, and therefore preservation of oak stands is important to prevent the loss of fungal diversity. Finally, the distribution of the endophyte communities was related to some of the environmental variables considered. (Author) 42 refs.

  9. Managing redwood ecosystems using Sudden Oak Death as a silvicultural tool

    Science.gov (United States)

    Frederick D. Euphrat

    2015-01-01

    In response to the wave of sudden oak death (SOD), caused by Phytophthora ramorum, sweeping the redwood forest ecosystems of California's North Coast, the role of foresters and other ecosystem managers is being tested. On Bear Flat Tree Farm, near Healdsburg, California, Forest, Soil & Water, Inc. (FSW) has conducted a multi-year,...

  10. Seed Bank Variation under Contrasting Site Quality Conditions in Mixed Oak Forests of Southeastern Ohio, USA

    International Nuclear Information System (INIS)

    Small, Ch.J.; McCarthy, B.C.

    2010-01-01

    Seed bank composition was sampled in 192-2.5 m 2 quadrats, established in six regenerating clearcut (∼7 years) and six second-growth ((∼125 years) mixed-oak forest stands in southeastern Ohio. Seed bank and aboveground composition diverged markedly (Sorensen's coefficient <10%), emphasizing the importance of fast-growing, early-successional germinants to early ecosystem recovery. Seed richness was significantly (ρ<.01) higher in clearcut stands, suggesting declining richness with stand age. Richness estimations 28%-60% higher than observed values demonstrated high seed bank heterogeneity, emphasizing the need for intensive sampling to assess temperate forest seed bank variation. Site quality (topographic aspect) strongly influenced seed bank composition, with greater importance of early-successional trees, thicket-forming shrubs, and nonnative species on mesic sites. Thus, forest seed banks are likely to play an important, site-dependent role in shaping competitive environments for commercially important timber species after harvesting and soil disturbance and have the potential for marked influence on post harvest forest development.

  11. Effects of dust on forest tree health in Zagros oak forests.

    Science.gov (United States)

    Moradi, A; Taheri Abkenar, K; Afshar Mohammadian, M; Shabanian, N

    2017-10-10

    Dust is one of the most devastating factors for the environment threatening all animal and plant species. In many regions, the ecological and economic impact of microdust on scarce species is critical. In the western region of Iran, the Zagros forests have been exposed to dust storms for many years. In this study, the effect of dust on oak trees, the most important trees of Zagros forests, is investigated. For this purpose, 3-year-old seedlings of three species of oak trees under natural conditions were exposed to dust during spring and summer months. Seedlings were divided into two groups; one group was assigned as dust treatment and the other as control that the control group washed regularly to remove dust. Anatomical characteristics of leaves and dust deposits on leaves during the study period were examined by scanning electron microscope (SEM). The rate of photosynthesis and gas exchange in control and treated plants was examined by IRGA, LCI. SEM images showed that stomata structure, trichome density, and epicuticular waxes of leaves are different in all three species. This difference in micromorphology of species influences the effects of dust deposited on the leaves. A comparison of leaf species images in control and dust treatment showed that in dust treatment the percentage of stomata blocked by dust in three species (per unit area) of Quercus infectoria, Q. libni, and Q. brantii were 61/6, 48/4, and 38/1%, respectively. The results of leaf gas exchange investigation indicated that stomatal occlusion by dust had a negative impact on the examined parameters of three oak species (P ≤ 0.01). Thus, gas exchange and photosynthetic rates of the treated species were significantly reduced. The results of both parts of the study showed the vulnerability of the three species to dust as Q. infectoria > Q. libni > Q. brantii. Therefore, based on these findings, dust can disrupt the physiological activities of the studied species and the continuation of the

  12. Use of forest species associated to oak forests (Quercus humboldtii Bonpl.) for energetic purposes, in three villages of the Encino municipality in Santander

    International Nuclear Information System (INIS)

    Diaz Silva, Monica Rocio de las Mercedes

    2010-01-01

    We surveyed the firewood consumption for energetic purposes from the oak forest of the Patios Altos and Canada villages in Encino-Santander. Tools used to collect data were: structured surveys, open interviews and participant observation to those families dependent upon forest resources. Twenty-one species for domestic use were recorded, from which seven were related to the oak for est. The most preferred and used tree species was the Oak (Quercus humboldtii Bonpl) followed by the Laurel (Morella pubescens (Humb. and Bonpl. ex Willd.) Wilbur). Results show that 98% of the population uses only firewood and firewood alternated with gas, which suggests the importance of firewood to the community. Firewood consumption per person is 3.6 + - 1.35 kg per day, while annual consumption of the whole group (54 families) is the 354.78 kg per year. This usage corresponds to native tree species (78.2%), native shrubs 12.4%) and exotics (9.3%). Firewood usage represents savings to local inhabitants, corresponding to 33% of their monthly earnings, approximate Oak forest, Colombia, wood demand, native forest species, firewood, domestic use of wood.

  13. An Old-Growth Definition for Dry and Dry-Mesic Oak-Pine Forests.

    Science.gov (United States)

    David L. White; F. Thomas. Lloyd

    1998-01-01

    Dry and dry-mesic oak-pine forests are widely distributed from New Jersey to Texas, but representative old-growth stands are rare. Historical accounts of composition, along with information from existing old-growth stands, were used to characterize this type. Shortleaf pine and white oak were the most widely distributed trees across all old-growth stands. Shortleaf was...

  14. Development of a robust chromatographic method for the detection of chlorophenols in cork oak forest soils.

    Science.gov (United States)

    McLellan, Iain; Hursthouse, Andrew; Morrison, Calum; Varela, Adélia; Pereira, Cristina Silva

    2014-02-01

    A major concern for the cork and wine industry is 'cork taint' which is associated with chloroanisoles, the microbial degradation metabolites of chlorophenols. The use of chlorophenolic compounds as pesticides within cork forests was prohibited in 1993 in the European Union (EU) following the introduction of industry guidance. However, cork produced outside the EU is still thought to be affected and simple, robust methods for chlorophenol analysis are required for wider environmental assessment by industry and local environmental regulators. Soil samples were collected from three common-use forests in Tunisia and from one privately owned forest in Sardinia, providing examples of varied management practice and degree of human intervention. These provided challenge samples for the optimisation of a HPLC-UV detection method. It produced recoveries consistently >75% against a soil CRM (ERM-CC008) for pentachlorophenol. The optimised method, with ultraviolet (diode array) detection is able to separate and quantify 16 different chlorophenols at field concentrations greater than the limits of detection ranging from 6.5 to 191.3 μg/kg (dry weight). Application to a range of field samples demonstrated the absence of widespread contamination in forest soils at sites sampled in Sardinia and Tunisia.

  15. 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.

  16. The rhizosphere microbiome of burned holm-oak: potential role of the genus Arthrobacter in the recovery of burned soils.

    Science.gov (United States)

    Fernández-González, Antonio J; Martínez-Hidalgo, Pilar; Cobo-Díaz, José F; Villadas, Pablo J; Martínez-Molina, Eustoquio; Toro, Nicolás; Tringe, Susannah G; Fernández-López, Manuel

    2017-07-20

    After a forest wildfire, the microbial communities have a transient alteration in their composition. The role of the soil microbial community in the recovery of an ecosystem following such an event remains poorly understood. Thus, it is necessary to understand the plant-microbe interactions that occur in burned soils. By high-throughput sequencing, we identified the main bacterial taxa of burnt holm-oak rhizosphere, then we obtained an isolate collection of the most abundant genus and its growth promoting activities were characterised. 16S rRNA amplicon sequencing showed that the genus Arthrobacter comprised more than 21% of the total community. 55 Arthrobacter strains were isolated and characterized using RAPDs and sequencing of the almost complete 16S rRNA gene. Our results indicate that isolated Arthrobacter strains present a very high genetic diversity, and they could play an important ecological role in interaction with the host plant by enhancing aerial growth. Most of the selected strains exhibited a great ability to degrade organic polymers in vitro as well as possibly presenting a direct mechanism for plant growth promotion. All the above data suggests that Arthrobacter can be considered as an excellent PGP rhizobacterium that may play an important role in the recovery of burned holm-oak forests.

  17. Proportion of root-derived acid phosphomonoesterase in total soil acid phosphomonoesterase in different forests

    Directory of Open Access Journals (Sweden)

    Ladislav Holík

    2011-01-01

    Full Text Available Enzyme acid phosphomonoesterase (APM plays an important role in phosphorus mineralization in different type of terrestrial ecosystems. This enzyme is of great agronomic significance because it hydrolyses organic phosphorus to different forms of inorganic phosphorus which are assimilable by plants. APM may also indicate changes in the quantity and quality of phosphorylated substrates in soil and is a good indicator of its biological state as well as presence of pollutants. APM may be produced by plant roots and soil microorganisms and both of these sources may play different role in phosphorus mineralization in different ecosystems. The aim of this work was determine acid phosphomonoesterase (APM activity location in soil of different forest ecosystems. The APM activity location determination was performed on the basis of root-derived and soil-derived APM and expression of proportion of those root-derived in total soil APM up to 13 cm depth. The results of this preliminary study showed that root-derived APM formed 21–34 % of total soil APM in pine and oak forest.

  18. Responses of northern red oak seedlings to lime and deer exclosure fencing in Pennsylvania

    Science.gov (United States)

    Robert P. Long; Patrick H. Brose; Stephen B. Horsley

    2012-01-01

    In Pennsylvania, two hypotheses compete to explain the chronic oak (Quercus spp.) regeneration problem: excessive deer browsing and soil cation depletion. We tested these hypotheses by evaluating the effect of forest liming and deer exclosure fencing on northern red oak (Quercus rubra L.) seedling growth and nutrition in five...

  19. Seed Bank Variation under Contrasting Site Quality Conditions in Mixed Oak Forests of Southeastern Ohio, USA

    Directory of Open Access Journals (Sweden)

    Christine J. Small

    2010-01-01

    Full Text Available Seed bank composition was sampled in 192–2.5 m2 quadrats, established in six regenerating clearcut (∼7 years and six second-growth (∼125 years mixed-oak forest stands in southeastern Ohio. Seed bank and aboveground composition diverged markedly (Sørensen's coefficient <10%, emphasizing the importance of fast-growing, early-successional germinants to early ecosystem recovery. Seed richness was significantly (P<.01 higher in clearcut stands, suggesting declining richness with stand age. Richness estimations 28%–60% higher than observed values demonstrated high seed bank heterogeneity, emphasizing the need for intensive sampling to assess temperate forest seed bank variation. Site quality (topographic aspect strongly influenced seed bank composition, with greater importance of early-successional trees, thicket-forming shrubs, and nonnative species on mesic sites. Thus, forest seed banks are likely to play an important, site-dependent role in shaping competitive environments for commercially important timber species after harvesting and soil disturbance and have the potential for marked influence on postharvest forest development.

  20. Climate change impact on a mixed lowland oak stand in Serbia

    Directory of Open Access Journals (Sweden)

    Dejan Stojanović

    2015-12-01

    Full Text Available Climatic changes and bad environmental conditions may lead to forests vitality loss and even mortality. This is the reason why increased sanitary felling operations were performed in mixed oak forests in northern Serbia in 2013 in order to solve the severe dieback which affected some Pedunculate oak (Quercus robur L. and Turkey oak (Quercus cerris L. stands, after the very dry years 2011 and 2012.Dendrochronological techniques were applied to both these oak species collected in a stand, to examine the impact of temperature, precipitation and ground water level on forest growth and investigate the potential causes of the dieback.Differences in tree-ring patterns between surviving and dead trees were not significant according to t-value (from 5.68 to 14.20 and Gleichläufigkeit coefficient (from 76% to 82%, this meaning no distinctive responses of the two ecologically different oak species. As for radial increment, pedunculate and Turkey oak trees showed a similar response to environmental variables in this mixed stand. The Simple Pearson’s correlation analysis, which was conducted, showed that among three basic environmental variables (the mean monthly air temperature, the monthly sum of precipitation and the mean monthly water level, proxy of ground water level, the water level of Danube river in May and the temperature in April were statistically related to the growth of the four tree groups: (i pedunculate oak vital, (ii pedunculate oak dead, (iii Turkey oak vital and (iv Turkey oak dead trees, for the period 1961-2010 (p<0.05, n=60. Similar phenomena had already been observed in the Sava River basin for the growth of pure pedunculate oak forests. The long-term decline of the Danube River water level may be related to climate variations and to the changes of water management, river bed, as well as land-use. Together with the increase of temperature, this decline of the water level, and its potential unavailability in the soil, represents a

  1. Goldspotted oak borer in California: Invasion history, biology, impact, management, and implications for Mediterranean forests worldwide

    Science.gov (United States)

    Tom Coleman; Steven Seybold

    2016-01-01

    In 2008, the goldspotted oak borer, Agrilus auroguttatus Schaeffer (Coleoptera: Buprestidae), was fi rst linked to elevated levels of oak mortality in southern California (CA), but it appears to have impacted oak woodlands and mixed conifer forests across all land ownerships in this region for nearly two decades. This unexpectedly damaging...

  2. Optimization Forest Thinning Measures for Carbon Budget in a Mixed Pine-Oak Stand of the Qingling Mountains, China: A Case Study

    Directory of Open Access Journals (Sweden)

    Lin Hou

    2016-11-01

    Full Text Available Forest thinning is a silviculture treatment for sustainable forest management. It may promote growth of the remaining individuals by decreasing stand density, reducing competition, and increasing light and nutrient availability to increase carbon sequestration in the forest ecosystem. However, the action also increases carbon loss simultaneously by reducing carbon and other nutrient inputs as well as exacerbating soil CO2 efflux. To achieve a maximum forest carbon budget, the central composite design with two independent variables (thinning intensity and thinning residual removal rate was explored in a natural pine-oak mixed stand in the Qinling Mountains, China. The net primary productivity of living trees was estimated and soil CO2 efflux was stimulated by the Yasso07 model. Based on two years observation, the preliminary results indicated the following. Evidently chemical compounds of the litter of the tree species affected soil CO2 efflux stimulation. The thinning residual removal rate had a larger effect than thinning intensity on the net ecosystem productivity. When the selective thinning intensity and residual removal rate was 12.59% and 66.62% concurrently, the net ecosystem productivity reached its maximum 53.93 t·ha−1·year−1. The lower thinning intensity and higher thinning residual removal rated benefited the net ecosystem productivity.

  3. Lighting intensity of the soilsurface and restocking of oak groves

    Science.gov (United States)

    Slepykh, Victor; Zubko, Anna; Povolotckaia, Nina

    2016-04-01

    Oak groves of Caucasian Mineral Vody region (CMVR) possess a high ecological and balneological potential which defines the significance of their preservation and reproduction [1]. The role assessment of lighting intensity on renewal of oak groves was carried out on four trial squares (ts) in natural sixty-seven years old forest stand with prevalence of English oak (Quercus robur L.) with unimodal sity (type of the habitat - C1). The illumination was measured at the grass level by the universal measuring instrument of meteoparameters ATT-9508 with an illumination sensor of ATA-1591. The assessment of reforestation was carried out according to the established standards [2]. In the winter of 2005 there was conducted a selecting cutting cabin of the forest stand according to a local method on ts2 with intensity 30%, on ts4 - 50% after which the illumination on the soil surface in relation to illumination of an open place in the summer of 2005 increased from 4.9% to 33.9% on ts2, and from 5.9% to 24.4% on ts4. But by 2014 the illumination decreased till 3.0% on ts2, till 5.4% on ts4 because of an intensive soil grassing down. The control was carried out by ts1 and ts3 on which from 2005 to 2014 the illumination of the soil surface decreased from 4 to 2% as a result of the development of all storeys. As a result due to an intensive soil grassing-down, the total quantity of young oak trees decreased from 2005 to 2014 from 25.6 thousand pcs/ha to 5.9 thousand pcs/ha on ts2; on from 17.3 thousand pcs/ha to 4.0 thousand pcs/ha on ts4. At the same time the total quantity of young oak trees on control squares increased respectively for 1.4% (from 18.8 thousand pcs/ha to 19.1 thousand pcs/ha) on ts1, for 38.7% (from 25.2 thousand pcs/ha to 41.1 thousand pcs/ha). The experiment showed that small young oak trees perishes in the first years of their life from a lack of light and competition from grasland vegetation without providing successful reforestation. Conclusion. So it is

  4. Prescribed burning effects on soil enzyme activity in a southern Ohio hardwood forest: A landscape-scale analysis

    Science.gov (United States)

    Ralph E. J. Boerner; Kelly L. M. Decker; Elaine K. Sutherland

    2000-01-01

    We assessed the effect of a single, dormant season prescribed fire on soil enzyme activity in oak-hickory (Quercus-Carya) forests in southern Ohio, USA. Four enzymes specific for different C sources were chosen for monitoring: acid phosphatase, beta-glucosidase, chitinase and phenol oxidase. Postfire acid phosphatase activity was generally reduced by burning and...

  5. Earthworms as indicators for different forest management types and human disturbance in Ilam oak forest, Iran

    Directory of Open Access Journals (Sweden)

    Heydari Mehdi

    2014-09-01

    Full Text Available There has been observed widespread destruction of natural ecosystems around the world due to population growth, land use change and clear cutting which have affected soil properties. Different management strategies have been so far implemented to reduce this crisis in various regions of the world, such as e.g. short-term and long-term conservation management in the Zagros region. However, any management approach should be evaluated with appropriate measures to determine how managed areas respond. The main objective of the present study was to evaluate the potential of earthworms as an indicator for different forest management strategies and human disturbances in Zagros oak (Quercus persica Jaub. and Spach forest. The sites selected included undisturbed one as the control (Un, the sites under five-year conservation management (FCM and twenty-year conservation management (TCM as well as the disturbed site (D. The results of principal component analysis (PCA showed that different regions separated into the components: PC1 and PC2. Un and TCM sites gathered together and represented higher values of the factors such as pH, Kavailable, OC, clay content, Pavailable, CEC, overstory tree canopy, Ntot, biomass and abundance of earthworms. The positive direction of the first axis reflected a gradient of EC, BD and Ptot. According to the logistic model, NH4-N and EC played the most important role in earthworm presence and absence in Zagros forest ecosystem. Earthworm abundance and biomass could be a good indicator to evaluate different forest management strategies in the study area.

  6. Mortality and community changes drive sudden oak death impacts on litterfall and soil nitrogen cycling.

    Science.gov (United States)

    Cobb, Richard C; Eviner, Valerie T; Rizzo, David M

    2013-10-01

    Few studies have quantified pathogen impacts to ecosystem processes, despite the fact that pathogens cause or contribute to regional-scale tree mortality. We measured litterfall mass, litterfall chemistry, and soil nitrogen (N) cycling associated with multiple hosts along a gradient of mortality caused by Phytophthora ramorum, the cause of sudden oak death. In redwood forests, the epidemiological and ecological characteristics of the major overstory species determine disease patterns and the magnitude and nature of ecosystem change. Bay laurel (Umbellularia californica) has high litterfall N (0.992%), greater soil extractable NO3 -N, and transmits infection without suffering mortality. Tanoak (Notholithocarpus densiflorus) has moderate litterfall N (0.723%) and transmits infection while suffering extensive mortality that leads to higher extractable soil NO3 -N. Redwood (Sequoia sempervirens) has relatively low litterfall N (0.519%), does not suffer mortality or transmit the pathogen, but dominates forest biomass. The strongest impact of pathogen-caused mortality was the potential shift in species composition, which will alter litterfall chemistry, patterns and dynamics of litterfall mass, and increase soil NO3 -N availability. Patterns of P. ramorum spread and consequent mortality are closely associated with bay laurel abundances, suggesting this species will drive both disease emergence and subsequent ecosystem function. © 2013 The Authors. New Phytologist © 2013 New Phytologist Trust.

  7. The symbiotic relationship between dominant canopy trees and soil microbes affects the nitrogen source utilization of co-existing understory trees

    Science.gov (United States)

    Iwaoka, C.; Hyodo, F.; Taniguchi, T.; Shi, W.; Du, S.; Yamanaka, N.; Tateno, R.

    2017-12-01

    The symbiotic relationship between dominant canopy trees and soil microbes such as mycorrhiza or nitrogen (N) fixer are important determinants of soil N dynamics of a forest. However, it is not known how and to what extent the symbiotic relationship of dominant canopy trees with soil microbes affect the N source of co-existing trees in forest. We measured the δ15N of surface soils (0-10 cm), leaves, and roots of the dominant canopy trees and common understory trees in an arbuscular mycorrhizal N-fixing black locust (Robinia pseudoacacia) plantation and an ectomycorrhizal oak (Quercus liaotungensis) natural forest in a China dryland. We also analyzed the soil dissolved N content in soil extracts and absorbed by ion exchange resin, and soil ammonia-oxidizer abundance using real-time PCR. The δ15N of soil and leaves were higher in the black locust forest than in the oak forest, although the δ15N of fine roots was similar in the two forests, in co-existing understory trees as well as dominant canopy trees. Accordingly, the δ15N of leaves was similar to or higher than that of fine roots in the black locust forest, whereas it was consistently lower than that of fine roots in the oak forest. In the black locust forest, the soil dissolved organic N and ammonium N contents were less abundant but the nitrate N contents in soils and absorbed by the ion exchange resin and ammonia-oxidizer abundance were greater, due to N fixation or less uptake of organic N from arbuscular mycorrhiza. In contrast, the soil dissolved organic N and ammonium N contents were more abundant in the oak forest, whereas the N content featured very low nitrate, due to ectomycorrhizal ability to access organic N. These results suggest that the main N source is nitrate N in the black locust forest, but dissolved organic N or ammonium N in the oak forest. N fixation or high N loss due to high N availability would cause high δ15N in soil and leaves in black locust forest. On the other hand, low soil N

  8. Nitrogen retention in contrasting temperate forests exposed to high nitrogen deposition

    Science.gov (United States)

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

    2011-12-01

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

  9. Species-specific Mechanisms Contributing to the Mesophication of Upland Oak Stands in the Absence of Fire

    Science.gov (United States)

    Babl, E. K.; Alexander, H. D.; Siegert, C. M.; Willis, J. L.; Berry, A. I.

    2017-12-01

    Upland oak forests of the eastern United States are shifting dominance towards shade-tolerant, fire-intolerant species. This shift is hypothesized to be driven by anthropogenic fire suppression and lead to mesophication, a positive feedback loop where shade-tolerant, fire-sensitive species (i.e. mesophytes) create a cool, moist understory, reducing forest flammability and promoting their own proliferation at the expense of pyrophytic, shade-intolerant species such as oaks. There have been few empirical studies identifying mechanisms of mesophication, and these studies have yet to extensively explore potential mesophytes other than red maple (Acer rubrum). To address this issue, we sampled four hypothesized mesophytes (A. rubrum, A. saccharum, Carya glabra, and Fagus grandifolia) and two upland oak species (Quercus alba and Q. montana) across a gradient of sizes (20-60 cm DBH) in western Kentucky. We quantified canopy, bark, and leaf litter traits among upland oaks and mesophytes that may lead to differences in forest flammability. Preliminary results show that mesophytes had thinner and smoother bark than upland oaks and an increased canopy volume (normalized to stem volume), traits known to influence water movement through the canopy and understory microclimate. Maple leaf litter also decomposed faster, which could decrease fuel loads; after 6 months, red and sugar maple leaf litter lost 37% of original mass compared to 32%, 22%, and 14% mass loss in hickory, oak, and American beech litter, respectively. Furthermore, volumetric soil moisture of the soil organic layer beneath the canopies of mesophytes was 62% moister two days following a rainfall event compared to oaks. These differences in soil organic layer water retention after rainfall could lead to fuel discontinuity. These findings suggest that mesophytes may alter future forest flammability through their bark, canopy, and leaf litter traits which may modify fuel moisture, loads, and continuity and that a

  10. Risk analysis and guidelines for harvest activities in wisconsin oak timberlands to minimize oak wilt threat

    Science.gov (United States)

    Jennifer Juzwik; Jane Cummings-Carlson; Kyoko Scanlon

    2010-01-01

    Oaks (Quercus spp.) are an important species group in the forests of Wisconsin. The State’s timberland typed as oak-hickory forest was estimated at 2.9 million acres in 1996. Growing stock volume for red oak was estimated at 2.4 billion cubic feet, whereas select white oak volume was estimated to be 927 million cubic feet. Oak wilt, the oak disease...

  11. The history of widespread decrease in oak dominance exemplified in a grassland--forest landscape

    Science.gov (United States)

    Brice B. Hanberry; Daniel C. Dey; Hong S. He

    2014-01-01

    Regionally-distinctive open oak forest ecosystems have been replaced either by intensive agriculture and grazing fields or by denser forests throughout eastern North America and Europe. To quantify changes in tree communities and density in the Missouri Plains, a grassland-forest landscape, we used historical surveys from1815 to 1864 and current surveys from 2004 to...

  12. Soil erosion and deposition before and after fire in oak savannas

    Science.gov (United States)

    Peter F. Ffolliott; Gerald J. Gottfried; Hui Chen; Aaron T. Kauffman; Cody L. Stropki; Daniel G. Neary

    2013-01-01

    Effects of low severity prescribed burning treatments and a wildfire on soil erosion and deposition in the oak savannas in the Southwestern Borderlands are reported. Measurements in the spring and fall, respectively, characterize soil movements following winter rains and high-intensity summer rainstorms. Annual values are also presented. Relationships between soil...

  13. Field test of foliar-spray herbicides to control mountain laurel in mature mixed-oak forests in western Maryland

    Science.gov (United States)

    Gary W. Miller; Patrick H. Brose; Jeffrey D. Kochenderfer; James N. Kochenderfer; Kurt W. Gottschalk; John R. Denning

    2016-01-01

    Successful oak (Quercus spp.) regeneration requires the presence of competitive sources of oak reproduction before parent oaks are harvested. Mountain laurel (Kalmia latifolia) in the understory of many Appalachian forests prevents new oak seedlings from receiving adequate sunlight to survive and grow into competitive size classes. This study examined the efficacy of...

  14. Regeneration of upper-elevation red oak in the White Mountains of New Hampshire

    Science.gov (United States)

    William B. Leak; Mariko. Yamasaki

    2013-01-01

    Northern red oak occurs in limited amounts with a mixture of softwoods on the shallow soils at upper elevations in northern New England. These stands are important for wildlife habitat and forest diversity as well as a modest amount of timber harvesting. Little experience or research is available on how to regenerate upper-elevation oak. However, an examination of a 35...

  15. [Impact of cork oak management on the ectomycorrhizal fungal diversity associated with Quercus suber in the Mâamora forest (Morocco)].

    Science.gov (United States)

    Maghnia, Fatima Z; Sanguin, Hervé; Abbas, Younes; Verdinelli, Marcello; Kerdouh, Benaissa; El Ghachtouli, Naima; Lancellotti, Enrico; Bakkali Yakhlef, Salah Eddine; Duponnois, Robin

    2017-05-01

    The cork oak forest is an ecosystem playing a major role in Moroccan socio-economy and biodiversity conservation. However, this ecosystem is negatively impacted by extensive human- and climate-driven pressures, causing a strong decrease in its distribution and a worsening of the desertification processes. This study aims at characterising the impact of cork oak forest management on a major actor of its functioning, the ectomycorrhizal (EcM) fungal community associated with Quercus suber, and the determination of EcM bio-indicators. The EcM fungal community has been monitored during spring and winter seasons in two sites of the Moroccan Mâamora forest, corresponding to a forest site either impacted by human activities or protected. A significant impact of cork oak forest management on the EcM fungal community has been revealed, with major differences during the summer season. The results confirmed the potential ecological significance of several EcM fungi (e.g., Cenococcum) in the sustainability of the cork oak forest functioning, but also the significant association of certain EcM fungi (Pachyphloeus, Russula, Tomentella) with a perturbation or a season, and consequently to the cork oak forest status or to climatic conditions, respectively. The development of study at the Mediterranean scale may improve the robustness of ecological models to predict the impact of global changes on this emblematic ecosystem of Mediterranean basin. Copyright © 2017 Académie des sciences. Published by Elsevier Masson SAS. All rights reserved.

  16. Coarse woody debris facilitates oak recruitment in Bialowieza Primeval Forest, Poland

    NARCIS (Netherlands)

    Smit, Christian; Kuijper, Dries P. J.; Prentice, David; Wassen, Martin J.; Cromsigt, Joris P. G. M.

    2012-01-01

    While oaks contribute to the ecology and economy of temperate lowland forests, recruitment into larger size classes is generally scarce. Ungulate herbivory is a limiting factor for tree recruitment, thus natural structures protecting against ungulates may be important for recruitment success. We

  17. Changes in the species composition and structure of the herb layer of a thermophilous oak forest subject to clear cutting

    Directory of Open Access Journals (Sweden)

    Hieronim Andrzejewski

    2014-01-01

    Full Text Available Changes in the herb layer of a thermophilous oak forest (Potentillo albae-Quercetum, subject to clear cutting and artificial reforestation with Scotch pine monoculture, were analysed by a comparative method. It was found that cutting of a tree stand and underbrush did not destroy phytocoenose totally. Floristically-rich clearance communities resembled in their composition and structure the ground layer of an natural form of an oak forest. The regress of the herb layer took place several years later in a young pine stand. Then, a compact tree canopy highly restricted light inflow to the bottom of a forest. Later, thinning of a forest stand enabled the herb layer to regenerate. Nevertheless, even 60 years after clear cutting it significantly differed from the herb layer of a natural oak forest.

  18. Short-Term Effects of Understory and Overstory Management on Breeding Birds in Arkansas Oak-Hickory Forests

    Science.gov (United States)

    Paul G. Rodewald; Kimberly G. Smith

    1998-01-01

    Relatively little is known about the effects of uneven-aged forest management practices on eastern forest birds, despite the fact that such methods are now commonly practiced. In 1993-94, we studied the short-term effects of uneven-aged forest management on bird communities in oak-hickory forests of north-western Arkansas. We estimated bird abundance in mature forests...

  19. Stability of diameter distributions in a managed uneven-aged oak forest in the Ozark Highlands

    Science.gov (United States)

    Zhiming Wang; Paul S. Johnson; H. E. Garrett; Stephen R. Shifley

    1997-01-01

    We studied a privately owned 156,000-acre oak-dominated forest in the Ozark Highlands of southern Missouri. The forest has been managed by the single-tree selection method since 1952. Using 40 years of continuous forest inventory records, we analyzed the stability of the shape of tree diameter distributions at the forest-wide scale. Results show that for trees ...

  20. Effect of long-term understory prescribed burning on standing and down dead woody material in dry upland oak forests

    Science.gov (United States)

    Polo, John A.; Hallgren, S.W.; Leslie,, David M.

    2013-01-01

    Dead woody material, long ignored or viewed as a nuisance for forest management, has gained appreciation for its many roles in the forest including wildlife habitat, nutrient storage and cycling, energy for trophic webs, protection of soil, fuel for fire and carbon storage. The growing interest in managing dead woody material has created strong demand for greater understanding of factors controlling amounts and turnover. Prescribed burning, an important management tool, may have strong effects of dead woody material given fire’s capacity to create and consume dead woody material. We determined effects of long-term understory prescribed burning on standing and down woody material in upland oak forests in south-central North America. We hypothesized that as frequency of fire increased in these stands the amount of deadwood would decrease and the fine woody material would decrease more rapidly than coarse woody material. The study was conducted in forests dominated by post oak (Quercus stellata) and blackjack oak (Quercus marilandica) in wildlife management areas where understory prescribed burning had been practiced for over 20 years and the range of burn frequencies was 0 (unburned) fires per decade (FPD) to 4.6 FPD. The amount of deadwood was low compared with more productive forests in southeastern North America. The biomass (24.7 Mg ha-1) and carbon stocks (11.7 Mg ha-1) were distributed among standing dead (22%), coarse woody debris (CWD, dia. > 7.5 cm., 12%), fine woody debris (FWD, dia. prescribed burning influenced the amount and size distribution of standing and down dead woody material. There were two explanations for the lack of a detectable effect. First, a high incidence of severe weather including ice storms and strong winds that produce large amounts of deadwood intermittently in an irregular pattern across the landscape may preclude detecting a strong effect of understory prescribed burning. Second, fire suppression during the first one-half of the

  1. Effects of tornado damage, prescribed fire, and salvage logging on natural oak (Quercus spp.) regeneration in a xeric southern USA Coastal Plain oak/pine forest

    Science.gov (United States)

    Jeffery B. Cannon; J. Stephen Brewer

    2013-01-01

    Due in large part to fire exclusion, many oak-dominated (Quercus spp.) forests, woodlands, and savannas throughout eastern North America are being replaced by less diverse forest ecosystems. In the interior coastal plain of the southern United States, these forests are dominated in the mid- and understory by mesophytic species such as Acer...

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

    Science.gov (United States)

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

    2009-04-01

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

  3. Influence of Soil Type and Drainage on Growth of Swamp Chestnut Oak (Quercus Michauxii Nutt.) Seedlings

    Science.gov (United States)

    Donald D. Hook

    1969-01-01

    Swamp chestnut oak (Quercus michauxii Nutt.) seedlings were grown for 2 years in five soil types in drained and undrained pots. First-year height growth was related to soil type and pot drainage, but second-year height growth was related only to soil type. Results suggest that swamp chestnut oak is site-sensitive. But slow growth, a maximum of 2...

  4. The dynamic response of housing values to a forest invasive disease: evidence from a sudden oak death infestation

    Science.gov (United States)

    Kent Kovacs; Thomas P Holmes; Jeffrey E Englin; Janice Alexander

    2011-01-01

    “Sudden Oak Death” (Phytophthora ramorum) is a non-indigenous forest pathogen which causes substantial mortality of coast live oak (Quercus agrifolia) and several other oak tree species on the Pacific Coast of the United States. We estimated the time path of residential property values subject to oak mortality using a dataset that spans more than two decades—including...

  5. Comparison of Ant Community Diversity and Functional Group Composition Associated to Land Use Change in a Seasonally Dry Oak Forest.

    Science.gov (United States)

    Cuautle, M; Vergara, C H; Badano, E I

    2016-04-01

    Ants have been used to assess land use conversion, because they reflect environmental change, and their response to these changes have been useful in the identification of bioindicators. We evaluated ant diversity and composition associated to different land use change in a temperate forest (above 2000 m asl) in Mexico. The study was carried out in "Flor del Bosque" Park a vegetation mosaic of native Oak Forests and introduced Eucalyptus and grasslands. Species richness, dominance and diversity rarefaction curves, based on ant morphospecies and functional groups, were constructed and compared among the three vegetation types, for the rainy and the dry seasons of 2008-2009. Jaccard and Sorensen incidence-based indices were calculated to obtain similarity values among all the habitats. The Oak Forest was a rich dominant community, both in species and functional groups; the Eucalyptus plantation was diverse with low dominance. The most seasonality habitat was the grassland, with low species and high functional group diversity during the dry seasons, but the reverse pattern during the wet season. The Oak Forest was more similar to the Eucalyptus plantation than to the grassland, particularly during the dry season. Oak Forests are dominated by Cold Climate Specialists, specifically Prenolepis imparis (Say). The Eucalyptus and the grassland are characterized by generalized Myrmicinae, as Pheidole spp. and Monomorium ebenium (Forel). The conservation of the native Oak Forest is primordial for the maintenance of Cold Climate Specialist ant communities. The microclimatic conditions in this forest, probably, prevented the invasion by opportunistic species.

  6. Soil properties linked to Phytophthora cinnamomi presence and oak decline in Iberian dehesas

    Science.gov (United States)

    Moreno, G.; Vivas, M.; Pérez, A.; Cubera, E.; Madeira, M.; Solla, A.

    2009-04-01

    Dehesas cover about 3,100,000 ha in the Iberian Peninsula, and support an outstanding diversity of wildlife and flora endemisms. These open woodlands provide Spain and Portugal inhabitants with a high-quality food, derived from animal production, sustain rural population, and act as retardants of soil erosion and desertification, which are considered primary environmental concerns in the Mediterranean basin. Dehesas are considered examples of sustainable use, though in the last few decades intensive land use, imposed by a concomitant change in the technological and socio-economic conditions, and common agricultural policies threat their conservation. Soil compaction and erosion, oak regeneration failure, dieback of old-ageing stands, and loose of biodiversity are some of the most common threats. At the same time, a severe decline of Quercus ilex (Holm oak) has been reported since the 1990s in the southern Iberian Peninsula, and more recently in France, Italy, and Morocco. In the Iberian Peninsula, the decline has been mostly observed in dehesas, where a combination of factors, possibly acting in synergy, have been put forward to explain the disease. Severe drought episodes, flooding, and rapid fluctuations in soil water content have been reported as predisposing factors favoring tree invasion by bark borer insects and/or pathogenic fungi. It is mostly ignored to what extent decline is a natural or a man-induced process, and if it is associated to either basic, management-related soil properties, or both. To bring insight to this problem, extensive and integrative comparisons of some soil properties related to hydromorphism were initiated, comprising pairs of adjacent non-symptomatic and symptomatic Q. ilex trees. In 2008, 48 dehesa stands from western Spain (Cáceres), half of them located along stream banks and the other half located in slopes, were intensively studied. In each stand, soil and root samples were taken under 3 non-symptomatic (healthy) and 3

  7. Changes in Gambel oak densities in southwestern ponderosa pine forests since Euro-American settlement

    Science.gov (United States)

    Scott R. Abella; Peter Z. Fulé

    2008-01-01

    Densities of small-diameter ponderosa pine (Pinus ponderosa) trees have increased in southwestern ponderosa pine forests during a period of fire exclusion since Euro-American settlement in the late 1800s. However, less well known are potential changes in Gambel oak (Quercus gambelii) densities during this period in these forests....

  8. Habitat use by bats in two Indiana forests prior to silvicultural treatments for oak regeneration

    Science.gov (United States)

    Jeremy J. Sheets; Joseph E. Duchamp; Megan K. Caylor; Laura D' Acunto; John O. Whitaker; Virgil Jr. Brack; Dale W. Sparks

    2013-01-01

    As part of a study examining the effects of silvicultural treatments for oak regeneration on habitat use by bats, we surveyed forest stands prior to the implementation of treatments in two state forests in Indiana. Interior forest sites corresponding to areas designated for silvicultural treatments were surveyed for 2 nights each during the summers of 2007 and 2008....

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

    Science.gov (United States)

    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...

  10. Soil organic phosphorus in soils under different land use systems in northeast Germany

    Science.gov (United States)

    Slazak, Anna; Freese, Dirk; Hüttl, Reinhard F.

    2010-05-01

    Phosphorus (P) is commonly known as a major plant nutrient, which can act as a limiting factor for plant growth in many ecosystems, including different land use systems. Organic P (Po), transformations in soil are important in determining the overall biological availability of P and additionally Po depletion is caused by land cultivation. It is expected that changes of land use modifies the distribution of soil P among the various P-pools (Ptotal, Plabile, Po), where the Plabile forms are considered to be readily available to plants and Po plays an important role with P nutrition supply for plants. The aim of the study was to measure the different soil P pools under different land use systems. The study was carried out in northeast of Brandenburg in Germany. Different land use systems were studied: i) different in age pine-oak mixed forest stands, ii) silvopastoral land, iii) arable lands. Samples were taken from two mineral soil layers: 0-10 and 10-20 cm. Recently, a variety of analytical methods are available to determine specific Po compounds in soils. The different P forms in the soil were obtained by a sequential P fractionation by using acid and alkaline extractants, which mean that single samples were subjected to increasingly stronger extractants, consequently separating the soil P into fractions based on P solubility. The soil Ptotal for the forest stands ranged from 100 to 183 mg kg -1 whereas Po from 77 to 148 mg kg -1. The Po and Plabile in both soil layers increased significantly with increase of age-old oak trees. The most available-P fraction was Plabile predominate in the oldest pine-oak forest stand, accounting for 29% of soil Ptotal. For the silvopasture and arable study sites the Ptotal content was comparable. However, the highest value of Ptotal was measured in the 30 years old silvopastoral system with 685 mg kg-1 and 728 mg kg-1 at 0-10 cm and 10-20 cm depth, respectively than in arable lands. The results have shown that the 30 years old

  11. Comparison of Tillandsia usneoides (Spanish moss) water and leachate dynamics between urban and pristine barrier island maritime oak forests

    Science.gov (United States)

    Van Stan, J. T.; Stubbins, A.; Reichard, J. S.; Wright, K.; Jenkins, R. B.

    2013-12-01

    Epiphyte coverage on forest canopies can drastically alter the volume and chemical composition of rainwater reaching soils. Along subtropical and tropical coastlines Tillandisa usneoides L. (Spanish moss), in particular, can envelop urban and natural tree crowns. Several cities actively manage their 'moss' covered forest to enhance aesthetics in the most active tourist areas (e.g., Savannah GA, St. Augustine FL, Charleston SC). Since T. usneoides survives through atmospheric water and solute exchange from specialized trichomes (scales), we hypothesized that T. usneoides water storage dynamics and leachate chemistry may be altered by exposure to this active urban atmosphere. 30 samples of T. usneoides from managed forests around the tourist center of Savannah, Georgia, USA were collected to compare with 30 samples from the pristine maritime live oak (Quercus virginiana Mill.) forests of a nearby undeveloped barrier island (St. Catherines Island, Georgia, USA). Maximum water storage capacities were determined via submersion (for all 60 samples) along with dissolved ion (DI) and organic matter (DOM) concentrations (for 15 samples each) after simulated throughfall generation using milliQ ultrapurified water. Further, DOM quality was evaluated (for 15 samples each) using absorbance and fluorescence spectroscopy (EEMS). Results show significant alterations to water storage dynamics, DI, DOM, and DOM quality metrics under urban atmospheric conditions, suggesting modified C and water cycling in urban forest canopies that may, in turn, influence intrasystem nutrient cycles in urban catchment soils or streams via runoff.

  12. Soil types and forest canopy structures in southern Missouri: A first look with AIS data

    Science.gov (United States)

    Green, G. M.; Arvidson, R. E.

    1986-01-01

    Spectral reflectance properties of deciduous oak-hickory forests covering the eastern half of the Rolla Quadrangle were examined using Thematic Mapper (TM) data acquired in August and December, 1982 and Airborne Imaging Spectrometer (AIS) data acquired in August, 1985. For the TM data distinctly high relative reflectance values (greater than 0.3) in the near infrared (Band 4, 0.73 to 0.94 micrometers) correspond to regions characterized by xeric (dry) forests that overlie soils with low water retention capacities. These soils are derived primarily from rhyolites. More mesic forests characterized by lower TM band 4 relative reflectances are associated with soils of higher retention capacities derived predominately from non-cherty carbonates. The major factors affecting canopy reflectance appear to be the leaf area index (LAI) and leaf optical properties. The Suits canopy reflectance model predicts the relative reflectance values for the xeric canopies. The mesic canopy reflectance is less well matched and incorporation of canopy shadowing caused by the irregular nature of the mesic canopy may be necessary. Preliminary examination of high spectral resolution AIS data acquired in August of 1985 reveals no more information than found in the broad band TM data.

  13. Soil carbon accumulation and nitrogen retention traits of four tree species grown in common gardens

    DEFF Research Database (Denmark)

    Gurmesa, Geshere Abdisa; Schmidt, Inger Kappel; Gundersen, Per

    2013-01-01

    explored. Effects of four tree species on soil C and N stocks and soil water nitrate concentration below the root zone were evaluated in a common garden design replicated at eight sites in Denmark. The tree species were beech (Fagus sylvatica L.), oak (Quercus robur L.), larch (Larix leptolepis Kaempf......), and Norway spruce (Picea abies (L) Karst.). After four decades, there were significant differences in forest floor C stocks among all four species, and C stocks increased consistently in the order oak Forest floor N stocks only...... differed significantly between conifers and broadleaves. The observed differences in forest floor C and N stocks were attributed to differences in litter turnover rates among the tree species. Mineral soil C stocks were significantly higher in stands of Norway spruce than in stands of oak and beech while...

  14. 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.

  15. Foliage response of young central European oaks to air warming, drought and soil type.

    Science.gov (United States)

    Günthardt-Goerg, M S; Kuster, T M; Arend, M; Vollenweider, P

    2013-01-01

    Three Central European oak species, with four provenances each, were experimentally tested in 16 large model ecosystem chambers for their response to passive air warming (AW, ambient +1-2 °C), drought (D, -43 to -60% irrigation) and their combination (AWD) for 3 years on two forest soil types of pH 4 or 7. Throughout the entire experiment, the influence of the different ambient and experimental climates on the oak trees was strong. The morphological traits of the Quercus species were affected in opposing ways in AW and D treatments, with a neutral effect in the AWD treatment. Biochemical parameters and LMA showed low relative plasticity compared to the morphological and growth parameters. The high plasticity in physiologically important parameters of the three species, such as number of intercalary veins or leaf size, indicated good drought acclimation properties. The soil type influenced leaf chlorophyll concentration, C/N and area more than drought, whereas foliage mass was more dependent on drought than on soil type. Through comparison of visible symptom development with the water deficits, a drought tolerance threshold of -1.3 MPa was determined. Although Q. pubescens had xeromorphic leaf characteristics (small leaf size, lower leaf water content, high LMA, pilosity, more chlorophyll, higher C/N) and less response to the treatments than Q. petraea and Q. robur, it suffered more leaf drought injury and shedding of leaves than Q. petraea. However, if foliage mass were used as the criterion for sustainable performance under a future climate, Q. robur would be the most appropriate species. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  16. A multi-century analysis of disturbance dynamics in pine-oak forests of the Missouri Ozark Highlands

    Science.gov (United States)

    Chad King; Rose-Marie. Muzika

    2013-01-01

    Using dendrochronology and growth release approaches, we analyzed the disturbance history of shortleaf pine (Pinus echinata Mich.) white oak (Quercus alba L.) forests in the Missouri Ozark Highlands. The objectives of this study were to (1) identify growth release events using living and remnant shortleaf pine and white oak, (2)...

  17. [Biogeochemical cycles in natural forest and conifer plantations in the high mountains of Colombia].

    Science.gov (United States)

    León, Juan Diego; González, María Isabel; Gallardo, Juan Fernando

    2011-12-01

    Plant litter production and decomposition are two important processes in forest ecosystems, since they provide the main organic matter input to soil and regulate nutrient cycling. With the aim to study these processes, litterfall, standing litter and nutrient return were studied for three years in an oak forest (Quercus humboldtii), pine (Pinus patula) and cypress (Cupressus lusitanica) plantations, located in highlands of the Central Cordillera of Colombia. Evaluation methods included: fine litter collection at fortnightly intervals using litter traps; the litter layer samples at the end of each sampling year and chemical analyses of both litterfall and standing litter. Fine litter fall observed was similar in oak forest (7.5 Mg ha/y) and in pine (7.8 Mg ha/y), but very low in cypress (3.5 Mg ha/y). Litter standing was 1.76, 1.73 and 1.3 Mg ha/y in oak, pine and cypress, respectively. The mean residence time of the standing litter was of 3.3 years for cypress, 2.1 years for pine and 1.8 years for oak forests. In contrast, the total amount of retained elements (N, P, S, Ca, Mg, K, Cu, Fe, Mn and Zn) in the standing litter was higher in pine (115 kg/ha), followed by oak (78 kg/ha) and cypress (24 kg/ha). Oak forests showed the lowest mean residence time of nutrients and the highest nutrients return to the soil as a consequence of a faster decomposition. Thus, a higher nutrient supply to soils from oaks than from tree plantations, seems to be an ecological advantage for recovering and maintaining the main ecosystem functioning features, which needs to be taken into account in restoration programs in this highly degraded Andean mountains.

  18. Sludge application and monitoring program on the Oak Ridge Reservation, 1986--1993

    Energy Technology Data Exchange (ETDEWEB)

    Gunderson, C.A.; Larsen, I.L.; Boston, H.L.; Bradburn, D.M. [Oak Ridge National Lab., TN (United States); Van Miegroet, H. [Utah State Univ., Logan, UT (United States). Dept. of Forest Resources; Morris, J.L. [Jaycor, Inc., Oak Ridge, TN (United States); Walzer, A.E. [Lockheed Martin Energy Systems, Oak Ridge, TN (United States). Central Environmental Compliance; Adler, T.C. [Bechtel National, Inc., Oak Ridge, TN (United States); Huq, M. [Oak Ridge Associated Universities, TN (United States)

    1995-09-01

    Municipal sewage sludge has been applied to forests and pastures on the Oak Ridge Reservation since 1983 as a method of both disposal and beneficial reuse. Application was carried out under Tennessee permits issued to the city of Oak Ridge for land disposal of sewage sludge. In conjunction with these applications, information has been collected concerning sludge quantity and characteristics, soil parameters, soil water constituents, groundwater quality, surface runoff water quality, and various chemical constituents in vegetation on application sites. This information provides (1) a record of sludge application on the DOE reservations and (2) documentation of changes in soil parameters following sludge application. The information also provides a basis for evaluating the implications of the land application of municipal sewage sludge for soil and water quality and for evaluating the fate of sludge constituents when sludge is either sprayed or injected on pasture sites or surface applied in forested sites. This report covers in detail sludge applications conducted from 1986 through 1993, with some data from the period between 1983 and 1986. Anaerobically digested liquid sludge (2% to 4% solids) from the city of Oak Ridge had a relatively high nitrogen content (8% dry weight) and average to low concentrations of potentially problematic metals, compared with typical municipal sludges. Few potentially hazardous organic chemicals were detected in the sludge, and when found, these were at very low concentrations. Oak Ridge sludge is somewhat unique in that it contains radionuclides ({sup 137}Cs, {sup 60}Co, {sup 131}I, uranium isotopes, {sup 90}Sr, and occasionally {sup 99}Tc) at concentrations much higher than typical municipal sludges. Land application of sewage sludge can dilute or destroy problematic sludge constituents while improving soil fertility. Correct management has made these sludge applications a model of environmentally responsible waste management.

  19. Fire behavioral changes as a result of sudden oak death in coastal California forests

    Science.gov (United States)

    Y. Vlachovic; C. Lee; H. Scanlon; J.M. Varner; R. Glebocki; B.D. Graham; D.M. Rizzo

    2013-01-01

    Field observations and anecdotal evidence suggest that sudden oak death (SOD), a disease caused by the pathogen Phytophthora ramorum, may alter fuel loading in affected forests. Though it is reasonable to assume that a disease resulting in leaf blight, dead branches, and tree mortality would increase forest fuels, little work has been done to...

  20. Pedunculate oak forests (Quercus robur L. survey in the Ticino Regional Park (Italy by remote sensing

    Directory of Open Access Journals (Sweden)

    Rossini M

    2007-01-01

    Full Text Available Pedunculate oak forests (Quercus robur L. in the Ticino Regional Park (Italy show sensible damage conditions due to different environmental stresses: insect attacks, summer drought and air pollution. Knowing whether oaks are healthy or stressed can provide useful information in order to conserve the forest ecosystems and avoid the lost of valuable natural resources. Environmental stresses can affect tree biochemical and structural variables, such as the concentration, composition and efficiency in light harvesting of foliar pigments, and the Leaf Area Index (LAI. Interest in the use of these variables for forest condition assessment has recently increased because they can be indirectly estimated from remote observations at leaf and canopy level. In particular, in this research we found that total chlorophyll (Chl concentration, a biochemical variable related to crown discoloration rate, was the most suitable variable for the detection of pedunculate oak decline in the Ticino Park. A regression analysis between Chl concentration and optical indices computed from hyperspectral MIVIS data was performed in order to estimate Chl concentration from remote observations. The good correlation between field measurements of Chl concentration and MIVIS optical indices allowed the development of a model to map Chl concentration across the Ticino Park forested area. Promising results demonstrated that remotely sensed data can provide an accurate estimation of Chl concentration and indicated the potential of this technique for forest condition monitoring.

  1. Water use and carbon exchange of red oak- and eastern hemlock-dominated forests in the northeastern USA : implications for ecosystem-level effects of hemlock woolly adelgid

    International Nuclear Information System (INIS)

    Hadley, J.L.; Kuzeja, P.S.; Singh, S.

    2008-01-01

    This study used the eddy flux method to measure water use and carbon exchange of a red oak forest and an eastern hemlock-dominated forest located in north-central Massachusetts over a period of 2 years. The study demonstrated that water use by the red oak reached approximately 4 mm per day -1 . A maximum rate of 2 mm per day -1 was used by the eastern hemlock forest. Carbon (C) uptake rates were higher in the red oak forest than in the eastern hemlock forest. Measurements of sap flux suggested that transpiration of red oak and black birches in the eastern hemlock forest were approximately twice as high as transpiration rates observed for eastern hemlock. However, annual C storage of eastern hemlock was almost equal to C storage rates of the red oak forest, due to net C uptake by the hemlock during an unusually warm fall and spring. The study showed that C storage by eastern hemlock forests will increase as a result of climatic warming. Although forest water use will decrease as a result of eastern hemlock due to insect disturbances, the replacement of eastern hemlock by deciduous species such as red oak will increase water use during the summer-time in areas where hemlock is a predominant species. 24 refs., 5 tabs., 11 figs

  2. Twentieth-century shifts in forest structure in California: Denser forests, smaller trees, and increased dominance of oaks.

    Science.gov (United States)

    McIntyre, Patrick J; Thorne, James H; Dolanc, Christopher R; Flint, Alan L; Flint, Lorraine E; Kelly, Maggi; Ackerly, David D

    2015-02-03

    We document changes in forest structure between historical (1930s) and contemporary (2000s) surveys of California vegetation through comparisons of tree abundance and size across the state and within several ecoregions. Across California, tree density in forested regions increased by 30% between the two time periods, whereas forest biomass in the same regions declined, as indicated by a 19% reduction in basal area. These changes reflect a demographic shift in forest structure: larger trees (>61 cm diameter at breast height) have declined, whereas smaller trees (Forest composition in California in the last century has also shifted toward increased dominance by oaks relative to pines, a pattern consistent with warming and increased water stress, and also with paleohistoric shifts in vegetation in California over the last 150,000 y.

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

    Directory of Open Access Journals (Sweden)

    K. Pilegaard

    2006-01-01

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

  4. Decomposition and N cycling changes in redwood forests caused by sudden oak death

    Science.gov (United States)

    Richard C. Cobb; David M. Rizzo

    2012-01-01

    Phytophthora ramorum is an emergent pathogen in redwood forests which causes the disease sudden oak death. Although the disease does not kill coast redwood (Sequoia sempervirens), extensive and rapid mortality of tanoak (Notholithocarpus densiflorus) has removed this...

  5. Seasonal and Daily Dynamics of the CO2 Emission from Soils of Pinus koraiensis Forests in the South of the Sikhote-Alin Range

    Science.gov (United States)

    Ivanov, A. V.; Braun, M.; Tataurov, V. A.

    2018-03-01

    The presented study shows the results of measuring soil respiration in typical burozems (Dystric Cambisols) under mixed Korean pine-broadleaved forests in the southern part of the Primorskii (Far East) region of Russia growing under conditions of monsoon climate. The measurements were performed in 2014-2016 by the chamber method with the use of a portable infrared gas analyzer. Relative and total values of the CO2 efflux from the soil surface on four model plots were determined. The intensity of summer emission varied from 2.25 to 10.97 μmol/(m2 s), and the total CO2 efflux from the soils of four plots varied from 18.84 to 25.56 mol/m2. It is shown that a larger part of seasonal variability in the soil respiration is controlled by the soil temperature ( R 2 = 0.5-0.7); the soil water content also has a significant influence on the CO2 emission determining about 10% of its temporal variability. The daily dynamics of soil respiration under the old-age (200 yrs) forest have a significant relationship with the soil temperature ( R 2 = 0.51). The pyrogenic transformation of Pinus koraiensis forests into low-value oak forests is accompanied by an increase in the CO2 efflux from the soil.

  6. Forest composition modifies litter dynamics and decomposition in regenerating tropical dry forest.

    Science.gov (United States)

    Schilling, Erik M; Waring, Bonnie G; Schilling, Jonathan S; Powers, Jennifer S

    2016-09-01

    We investigated how forest composition, litter quality, and rainfall interact to affect leaf litter decomposition across three successional tropical dry forests in Costa Rica. We monitored litter stocks and bulk litter turnover in 18 plots that exhibit substantial variation in soil characteristics, tree community structure, fungal communities (including forests dominated by ecto- or arbuscular mycorrhizal host trees), and forest age. Simultaneously, we decomposed three standard litter substrates over a 6-month period spanning an unusually intense drought. Decay rates of standard substrates depended on the interaction between litter identity and forest type. Decomposition rates were correlated with tree and soil fungal community composition as well as soil fertility, but these relationships differed among litter types. In low fertility soils dominated by ectomycorrhizal oak trees, bulk litter turnover rates were low, regardless of soil moisture. By contrast, in higher fertility soils that supported mostly arbuscular mycorrhizal trees, bulk litter decay rates were strongly dependent on seasonal water availability. Both measures of decomposition increased with forest age, as did the frequency of termite-mediated wood decay. Taken together, our results demonstrate that soils and forest age exert strong control over decomposition dynamics in these tropical dry forests, either directly through effects on microclimate and nutrients, or indirectly by affecting tree and microbial community composition and traits, such as litter quality.

  7. The macrofungal diversity and community of Atlantic oak (Quercus petraea and Q. robur forests in Ireland

    Directory of Open Access Journals (Sweden)

    Harrington, Thomas J.

    2012-06-01

    Full Text Available The oak species Quercus petraea and Q. Robur are dominant canopy tree species of native deciduous forests in Ireland and coastal regions of Western Europe. These forests are typically plant species-rich, and can also have a rich fungal flora. This survey examined macrofungi found in five native oak sites across Ireland over three years. Overall, 94 macrofungal species belonging to 39 genera were discovered with Mycena, Lactarius, Russula and Cortinarius the most species-rich genera. The species accumulation curve did not show signs of levelling off, indicating that more sampling would reveal more new species. Species richness estimation using the Chao2 estimator indicated that up to 135 species may be present across all of our plots, with individual plots receiving estimates from 19 to 61 species per plot. Sampled-based rarefaction analysis showed no significant differences in macrofungal species richness between our plots. The five most common species were Laccaria amethystina, L. laccata, Stereum hirsutum, Armillaria mellea and Cortinarius flexipes. Comparisons of the results with results from oak forests in similar regions found that the communities in Great Britain were most similar to those found in Ireland. There were some key oak forest distinguishing fungal species from the family Boletaceae lacking from Irish oak forests. It is hypothesised that the historic deforestation of Ireland, caused a reduction of suitable habitats for Irish oak associated macrofungi, leading to the unspecific mycota found in the oak forests of this study. The threats to Atlantic oak forests in Ireland are briefly discussed.Las especies de Quercus petraea y Q. Robur se encuentran en bosques de Irlanda y regiones de influencia atlántica de Europa Occidental. Estos bosques, típicamente ricos en especies de plantas, presentan una abundante micobiota. Este estudio examina la diversidad de macromicetes en cinco bosques naturales de roble en Irlanda durante un

  8. Long-term trends of changes in pine and oak foliar nitrogen metabolism in response to chronic nitrogen amendments at Harvard Forest, MA.

    Science.gov (United States)

    Minocha, Rakesh; Turlapati, Swathi A; Long, Stephanie; McDowell, William H; Minocha, Subhash C

    2015-08-01

    We evaluated the long-term (1995-2008) trends in foliar and sapwood metabolism, soil solution chemistry and tree mortality rates in response to chronic nitrogen (N) additions to pine and hardwood stands at the Harvard Forest Long Term Ecological Research (LTER) site. Common stress-related metabolites like polyamines (PAs), free amino acids (AAs) and inorganic elements were analyzed for control, low N (LN, 50 kg NH4NO3 ha(-1) year(-1)) and high N (HN, 150 kg NH4NO3 ha(-1) year(-1)) treatments. In the pine stands, partitioning of excess N into foliar PAs and AAs increased with both N treatments until 2002. By 2005, several of these effects on N metabolites disappeared for HN, and by 2008 they were mostly observed for LN plot. A significant decline in foliar Ca and P was observed mostly with HN for a few years until 2005. However, sapwood data actually showed an increase in Ca, Mg and Mn and no change in PAs in the HN plot for 2008, while AAs data revealed trends that were generally similar to foliage for 2008. Concomitant with these changes, mortality data revealed a large number of dead trees in HN pine plots by 2002; the mortality rate started to decline by 2005. Oak trees in the hardwood plot did not exhibit any major changes in PAs, AAs, nutrients and mortality rate with LN treatment, indicating that oak trees were able to tolerate the yearly doses of 50 kg NH4NO3 ha(-1) year(-1). However, HN trees suffered from physiological and nutritional stress along with increased mortality in 2008. In this case also, foliar data were supported by the sapwood data. Overall, both low and high N applications resulted in greater physiological stress to the pine trees than the oaks. In general, the time course of changes in metabolic data are in agreement with the published reports on changes in soil chemistry and microbial community structure, rates of soil carbon sequestration and production of woody biomass for this chronic N study. This correspondence of selected metabolites

  9. Technical note: Application of geophysical tools for tree root studies in forest ecosystems in complex soils

    Directory of Open Access Journals (Sweden)

    U. Rodríguez-Robles

    2017-11-01

    Full Text Available While semiarid forests frequently colonize rocky substrates, knowledge is scarce on how roots garner resources in these extreme habitats. The Sierra San Miguelito Volcanic Complex in central Mexico exhibits shallow soils and impermeable rhyolitic-rock outcrops, which impede water movement and root placement beyond the soil matrix. However, rock fractures, exfoliated rocks and soil pockets potentially permit downward water percolation and root growth. With ground-penetrating radar (GPR and electrical resistivity tomography (ERT, two geophysical methods advocated by Jayawickreme et al. (2014 to advance root ecology, we advanced in the method development studying root and water distribution in shallow rocky soils and rock fractures in a semiarid forest. We calibrated geophysical images with in situ root measurements, and then extrapolated root distribution over larger areas. Using GPR shielded antennas, we identified both fine and coarse pine and oak roots from 0.6 to 7.5 cm diameter at different depths into either soil or rock fractures. We also detected, trees anchoring their trunks using coarse roots underneath rock outcroppings. With ERT, we tracked monthly changes in humidity at the soil–bedrock interface, which clearly explained spatial root distribution of both tree species. Geophysical methods have enormous potential in elucidating root ecology. More interdisciplinary research could advance our understanding in belowground ecological niche functions and their role in forest ecohydrology and productivity.

  10. Influence of temperature and organic matter content on soil respiration in a deciduous oak forest

    Directory of Open Access Journals (Sweden)

    Zsolt Kotroczó

    2014-12-01

    Full Text Available The increasing temperature enhances soil respiration differently depend on different conditions (soil moisture, soil organic matter, the activity of soil microbes. It is an essential factor to predicting the effect of climate change on soil respiration. In a temperate deciduous forest (North-Hungary we added or removal aboveground and belowground litter to determine total soil respiration. We investigated the relationship between total soil CO2 efflux, soil moisture and soil temperature. Soil CO2 efflux was measured at each plot using chamber based soil respiration measurements. We determined the temperature sensitivity of soil respiration. The effect of doubled litter was less than the effect of removal. We found that temperature was more influential in the control of soil respiration than soil moisture in litter removal treatments, particularly in the wetter root exclusion treatments (NR and NI (R2: 0.49-0.61. Soil moisture (R2: 0.18-0.24 and temperature (R2: 0.18-0.20 influenced soil respiration similarly in treatments, where soil was drier (Control, Double Litter, Double Wood. A significantly greater increase in temperature induced higher soil respiration were significantly higher (2-2.5-fold in root exclusion treatments, where soil was wetter throughout the year, than in control and litter addition treatments. The highest bacterial and fungal count was at the DL treatment but the differences is not significant compared to the Control. The bacterial number at the No Litter, No Root, No Input treatment was significantly lower at the Control. Similar phenomenon can be observed at the fungal too, but the differences are not significant. The results of soil respiration suggest that the soil aridity can reduce soil respiration increases with the temperature increase. Soil bacterial and fungal count results show the higher organic matter content and soil surface cover litter favors the activity.

  11. Why is seed production so variable among individuals? A ten-year study with oaks reveals the importance of soil environment.

    Science.gov (United States)

    Pérez-Ramos, Ignacio M; Aponte, Cristina; García, Luis V; Padilla-Díaz, Carmen M; Marañón, Teodoro

    2014-01-01

    Mast-seeding species exhibit not only a large inter-annual variability in seed production but also considerable variability among individuals within the same year. However, very little is known about the causes and consequences for population dynamics of this potentially large between-individual variability. Here, we quantified seed production over ten consecutive years in two Mediterranean oak species - the deciduous Quercus canariensis and the evergreen Q. suber - that coexist in forests of southern Spain. First, we calibrated likelihood models to identify which abiotic and biotic variables best explain the magnitude (hereafter seed productivity) and temporal variation of seed production at the individual level (hereafter CVi), and infer whether reproductive effort results from the available soil resources for the plant or is primarily determined by selectively favoured strategies. Second, we explored the contribution of between-individual variability in seed production as a potential mechanism of satiation for predispersal seed predators. We found that Q. canariensis trees inhabiting moister and more fertile soils were more productive than those growing in more resource-limited sites. Regarding temporal variation, individuals of the two studied oak species inhabiting these resource-rich environments also exhibited larger values of CVi. Interestingly, we detected a satiating effect on granivorous insects at the tree level in Q. suber, which was evident in those years where between-individual variability in acorn production was higher. These findings suggest that individual seed production (both in terms of seed productivity and inter-annual variability) is strongly dependent on soil resource heterogeneity (at least for one of the two studied oak species) with potential repercussions for recruitment and population dynamics. However, other external factors (such as soil heterogeneity in pathogen abundance) or certain inherent characteristics of the tree might be

  12. Binding, distribution, and plant uptake of mercury in a soil from Oak Ridge, Tennessee, USA.

    Science.gov (United States)

    Han, Fengxiang X; Su, Yi; Monts, David L; Waggoner, Charles A; Plodinec, M John

    2006-09-15

    A large amount of mercury has been discharged on the U.S. Department of Energy's Oak Ridge Site (Tennessee) as a part of the U.S. nuclear weapon program during the 1950s through the early 1960s. Increases in mercury concentration in fish and in lower East Fork Poplar Creek of Oak Ridge have been recently reported. This is an experimental study mimicking the initial stage of transformation and redistribution of mercury in soils, which are comparable to those of the Oak Ridge site. The objectives of this study were to investigate potential transformation, distribution, and plant uptake of mercury compounds in soils. Results show that the H(2)O(2)-oxidizable mercury fraction (organically bound mercury) was the major solid-phase fraction in soils freshly contaminated with soluble mercury compounds, while cinnabar fraction was the major solid phase fraction in soils contaminated with HgS. Langmuir relationships were found between mercury concentrations in plant shoots and in soil solid-phase components. Mercury in HgS-contaminated soils was to some extent phytoavailable to plants. Mercury transformation occurred from more labile fractions into more stable fractions, resulting in strong binding of mercury and decreasing its phytoavailability in soils. In addition, high mercury losses from soils contaminated with soluble mercury compounds were observed during a growing season through volatilization, accounting for 20-62% of the total initial mercury in soils.

  13. Comparative distribution of plutonium in contaminated ecosystems at Oak Ridge, Tennessee, and Los Alamos, New Mexico

    International Nuclear Information System (INIS)

    Dahlman, R.C.; Garten, C.T. Jr.; Hakonson, T.E.

    1980-01-01

    The distribution of plutonium was compared in portions of forest ecosystems at Oak Ridge, TN, and Los Alamos, NM, which were contaminated by liquid effluents. Inventories of plutonium in soil at the two sites were generally similar, but a larger fraction of the plutonium was associated with biota at Los Alamos than at Oak Ridge. Most (99.7 to 99.9%) of the plutonium was present in the soil, and very little (0.1 to 0.3%) was in biotic components. Comparative differences in distributions within the two ecosystems appeared to be related to individual contamination histories and greater physical transport of plutonium in soil to biotic surfaces at Los Alamos

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

    Directory of Open Access Journals (Sweden)

    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.

  15. Reallocation and nutrient use efficiency in Antioquia central forests

    International Nuclear Information System (INIS)

    Leon Pelaez, Juan; Gonzalez Hernandez, Maria; Gallardo Lancho, Juan

    2009-01-01

    We have studied nutrient related variables such as reallocation, nutrient use efficiency (NUE) and fine litter fall for three years in an oak forest Quercus humboldtii Bonpl. and also in some other forest plantations like pine, Pinus patula, and cypress, Cupressus lusitanica, in Antioquia, Colombia. Leaf litter quantities returned to the soil followed a falling sequence: oak (5313.3 kg ha-1 year-1) > pine (4866.5 kg ha-1 year-1) > cypress (2460.3 kg ha-1 year-1). The coniferous species showed the highest NUE for the majority of elements that were examined, except for P, which reached its absolute maximum in the oak forest -where a clear reallocation of this nutrient was also recorded-, probably because of its reduced availability in these volcanic ash-derived soils. Nutrient reallocation allows the conservation of the nutrients by reducing its loss from leaching and litter-fall, thereby closing the nutrient cycle in this native forest. In fact, P gains from net deposition were found there -this includes foliar leaching and atmospheric deposition-, which indicates that the species absorbs the P contained in rainfall from the leaves before it reaches the forest ground. N slow-efficiency use was probably due to its low availability in soil, given its low mineralization rates in these montane forests. K showed the highest reallocation values. Such figures are influenced by its clearly mobile character, according to the highest net deposition levels also verified for this element. With the exception of Mg, there was no clear relationship between the reallocation process and NUE.

  16. 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.

  17. 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.

  18. Project plan for the Background Soil Characterization Project on the Oak Ridge Reservation, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1992-08-01

    The Background Soil characterization Project (BSCP) will provide background concentration levels of selected metals, organic compounds, and radionuclides in soils from uncontaminated on-site areas at the Oak Ridge Reservation (ORR), and off-site in the western part of Roane County and the eastern part of Anderson County. The BSCP will establish a database, recommend how to use the data for contaminated site assessment, and provide estimates of the potential human health and environmental risks associated with the background level concentrations of potentially hazardous constituents

  19. Project plan for the Background Soil Characterization Project on the Oak Ridge Reservation, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    1992-08-01

    The Background Soil characterization Project (BSCP) will provide background concentration levels of selected metals, organic compounds, and radionuclides in soils from uncontaminated on-site areas at the Oak Ridge Reservation (ORR), and off-site in the western part of Roane County and the eastern part of Anderson County. The BSCP will establish a database, recommend how to use the data for contaminated site assessment, and provide estimates of the potential human health and environmental risks associated with the background level concentrations of potentially hazardous constituents.

  20. Oak mortality associated with crown dieback and oak borer attack in the Ozark Highlands

    Science.gov (United States)

    Zhaofei Fan; John M. Kabrick; Martin A. Spetich; Stephen R. Shifley; Randy G. Jensen

    2008-01-01

    Oak decline and related mortality have periodically plagued upland oak–hickory forests, particularly oak species in the red oak group, across the Ozark Highlands of Missouri, Arkansas and Oklahoma since the late 1970s. Advanced tree age and periodic drought, as well as Armillaria root fungi and oak borer attack are believed to contribute to oak decline and mortality....

  1. 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...

  2. Comparison of growth response to thinning in oak forests managed as coppice with standards and high forest

    Science.gov (United States)

    Gautam, S.; Hasenauer, H.; Pietsch, S. A.

    2009-04-01

    The BIOME-BGC model integrates the main physical, biological and physiological processes based on current understanding of ecophysiology to assess forest ecosystem dynamics. This study evaluates the application of the model to assess the thinning effects on coppiced oak forests in Austria. We analyze the growth response, i.e. growth efficiency (GE), nitrogen use efficiency (NUE), water use efficiency (WUE) and radiation use efficiency (RUE) of oak forests to thinning. The results of coppice with standards and high forests simulations are analysed for differences in simulated growth response after thinning. The forest field data of the year 2006 and the respective model runs are used to evaluate model application. Strong positive relationship (r2 = 0.90) with unbiased results and statistically insignificant differences between predicted and observed volume allows the use of the model as a diagnostic tool to assess management effects. Results indicate that the coppice with standards exhibits a significantly higher yield by 2.97% (i.e. 10 cubic meters per hectare in one rotation), a higher harvest (49.9%) but a lower growing stock (19.69%) than the high forests. The higher growing stock and the lower extraction in the high forests confirm that the high forest sequestrates significantly more carbon than the coppice with standards. Results show that thinning leads to an increase in the GE, the NUE and the WUE, and to a decrease in the RUE. Although the coppice with standards forest ecosystem exhibits higher values in all studied growth parameters, only the difference in the NUE was statistically significant. This verifies that the difference in the yield between the coppice with standards and the high forests is mainly governed by the NUE difference in stands after thinning. The coppice with standards system produces an equal amount of net primary production while consuming significantly less nitrogen (16%) compared to the high forest system. In the coppice with

  3. Approaches to restoration of oak forests on farmed lowlands of the Mississippi River and its tributaries

    Science.gov (United States)

    Emile S. Gardiner; Daniel C. Dey; John A. Stanturf; Brian Roy. Lockhart

    2010-01-01

    The lowlands associated with the Mississippi River and its tributaries historically supported extensive broadleaf forests that were particularly rich in oak (Quercus spp.) species. Beginning in the 1700s, deforestation for agriculture substantially reduced the extent of the original forest, and fragmented the remainder into small parcels. More...

  4. Soil Management Plan for the Oak Ridge Y-12 National Security Complex Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    None

    2005-03-02

    This Soil Management Plan applies to all activities conducted under the auspices of the National Nuclear Security Administration (NNSA) Oak Ridge Y-12 National Security Complex (Y-12) that involve soil disturbance and potential management of waste soil. The plan was prepared under the direction of the Y-12 Environmental Compliance Department of the Environment, Safety, and Health Division. Soil disturbances related to maintenance activities, utility and building construction projects, or demolition projects fall within the purview of the plan. This Soil Management Plan represents an integrated, visually oriented, planning and information resource tool for decision making involving excavation or disturbance of soil at Y-12. This Soil Management Plan addresses three primary elements. (1) Regulatory and programmatic requirements for management of soil based on the location of a soil disturbance project and/or the regulatory classification of any contaminants that may be present (Chap. 2). Five general regulatory or programmatic classifications of soil are recognized to be potentially present at Y-12; soil may fall under one or more these classifications: (a) Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA) pursuant to the Oak Ridge Reservation (ORR) Federal Facilities Agreement; (b) Resource Conservation and Recovery Act (RCRA); (c) RCRA 3004(u) solid waste managements units pursuant to the RCRA Hazardous and Solid Waste Amendments Act of 1984 permit for the ORR; (d) Toxic Substances and Control Act-regulated soil containing polychlorinated biphenyls; and (e) Radiologically contaminated soil regulated under the Atomic Energy Act review process. (2) Information for project planners on current and future planned remedial actions (RAs), as prescribed by CERCLA decision documents (including the scope of the actions and remedial goals), land use controls implemented to support or maintain RAs, RCRA post-closure regulatory requirements for

  5. Restoring oak forest, woodlands and savannahs using modern silvicultural analogs to historic cultural fire regimes

    Science.gov (United States)

    Daniel C. Dey; Richard P. Guyette; Callie J. Schweitzer; Michael C. Stambaugh; John M. Kabrick

    2015-01-01

    Variability in historic fire regimes in eastern North America resulted in an array of oak savannahs, woodlands and forests that were dominant vegetation types throughout the region. In the past century, once abundant savannahs and woodlands have become scarce due to conversion to agriculture, or development of forest structure in the absence of fire. In addition, the...

  6. 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

  7. 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

  8. Ground truth assessments of forests affected by oak decline and red oak borer in the interior highlands of Arkansas, Oklahoma, and Missouri: preliminary results from overstory analysis

    Science.gov (United States)

    James M. Guldin; Edward A. Poole; Eric Heitzman; John M. Kabrick; Rose-Marie Muzika

    2006-01-01

    Forests of the Interior Highlands of Arkansas, Oklahoma, and Missouri are being affected by oak decline and an unprecedented outbreak of a native beetle called the red oak borer. On average, Interior Highlands stands contained 236 trees per acre, of which 32 trees per acre (13.4 percent) were dead or dying. Stands averaged 97 square feet per acre of basal area, of...

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

    Science.gov (United States)

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

    2014-12-01

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

  10. CpDNA haplotype variation reveals strong human influence on oak stands of the Veluwe forest in the Netherlands

    NARCIS (Netherlands)

    Buiteveld, J.; Koelewijn, H.P.

    2006-01-01

    We examined chloroplast DNA (cpDNA) variation in 78 oak stands of an important forest complex (the Veluwe) in The Netherlands. Based on historical maps and information oak stands were classified as planted or autochthonous. A genetic study by means of cpDNA haplotype characterisation was carried out

  11. Innovation and dedication underpin management of sudden oak death (Phytophthora ramorum) in California and Oregon forests

    Science.gov (United States)

    Susan J. Frankel

    2017-01-01

    This special issue of Forest Phytophthoras serves as part of the proceedings from the Sixth Sudden Oak Death Science Symposium held June 21 -23, 2016 at Fort Mason Center in San Francisco, CA, USA. The symposium marked almost 16 years to the day that David Rizzo (UC Davis) and Matteo Garbelotto (UC Berkeley) identified the cause of sudden oak death to be a previously...

  12. Origin, development, and impact of mountain laurel thickets on the mixed-oak forests of the central Appalachian Mountains, USA

    Science.gov (United States)

    Patrick H. Brose

    2016-01-01

    Throughout forests of the northern hemisphere, some species of ericaceous shrubs can form persistent understories that interfere with forest regeneration processes. In the Appalachian Mountains of eastern North America, mountain laurel (Kalmia latifolia) may interfere in the regeneration of mixed-oak (Quercus spp.) forests. To...

  13. Forest canopy structural controls over throughfall affect soil microbial community structure in an epiphyte-laden maritime oak stand

    Science.gov (United States)

    Van Stan, J. T., II; Rosier, C. L.; Schrom, J. O.; Wu, T.; Reichard, J. S.; Kan, J.

    2014-12-01

    Identifying spatiotemporal influences on soil microbial community (SMC) structure is critical to understanding of patterns in nutrient cycling and related ecological services. Since forest canopy structure alters the spatiotemporal patterning of precipitation water and solute supplies to soils (via the "throughfall" mechanism), is it possible changes in SMC structure variability could arise from modifications in canopy elements? Our study investigates this question by monitoring throughfall water and dissolved ion supply to soils beneath a continuum of canopy structure: from a large gap (0% cover) to heavy Tillandsia usneoides L. (Spanish moss) canopy (>90% cover). Throughfall water supply diminished with increasing canopy cover, yet increased washoff/leaching of Na+, Cl-, PO43-, and SO42- from the canopy to the soils (p < 0.01). Presence of T. usneoides diminished throughfall NO3-, but enhanced NH4+, concentrations supplied to subcanopy soils. The mineral soil horizon (0-10 cm) from canopy gaps, bare canopy, and T. usneoides-laden canopy significantly differed (p < 0.05) in soil chemistry parameters (pH, Ca2+, Mg2+, CEC). PCR-DGGE banding patterns beneath similar canopy covers (experiencing similar throughfall dynamics) also produced high similarities per ANalyses Of SIMilarity (ANO-SIM), and clustered together when analyzed by Nonmetric Multidimensional Scaling (NMDS). Correlation analysis of DGGE banding patterns, throughfall dynamics, and soil chemistry yielded significant correlations (p < 0.05) between fungal communities and soil chemical properties significantly differing between canopy cover types (pH: r2 = 0.50; H+ %-base saturation: r2 = 0.48; Ca2+ %-base saturation: r2 = 0.43). Bacterial community structure correlated with throughfall NO3-, NH4+, and Ca2+ concentrations (r2 = 0.37, p = 0.16). These results suggest that modifications of forest canopy structures are capable of affecting mineral-soil horizon SMC structure via the throughfall mechanism when

  14. Comparative analysis of some bioecological characteristics of Hungarian oak and Turkey oak

    Directory of Open Access Journals (Sweden)

    Vukin Marina

    2013-01-01

    Full Text Available This paper gives an in-depth study of some bioecological characteristics of the Hungarian and Turkey oak, autochthonous oak species and edificators of climatogenic communities of central Serbia. Today, these forest complexes are mostly of coppice origin and as such, they require implementation of reclamation operations. In order to determine biological dominance, select the optimal reclamation operations and finally improve the state of these forests, we studied the environmental conditions, stand state, development and position of individual trees in a mixed coppice stand of Hungarian and Turkey oak in a suburban zone of the city of Belgrade.

  15. Projected changes in the future distribution and production of sessile oak forests near the xeric limit

    Science.gov (United States)

    Gulyás, Krisztina; Berki, Imre; Veperdi, Gábor

    2017-04-01

    As a result of regional climate change, most European countries are experiencing an increase in mean annual temperature and CO2 concentration and a decrease in mean annual precipitation. In low-elevation areas in Southeast Europe, where precipitation is a limiting factor, the projected climate change threatens the health, production, and potential distribution of forest ecosystems. The intensive summer droughts and commonly occurring extreme weather events create negative influences that cause health declines, changes in yield potential, and tree mortality. Due to the observed damages, attention has been focused on these problems. The impacts of climatic extremes cause difficulties in forest management; these difficulties occur more frequently in Hungary, which is a region that is the most sensitive to climatic extremes. Regional climate model simulations project that the frequency of extremely high temperatures and long-term dry periods will increase; both of these factors have negative effects on future tree species distribution and production. Thus, the aim of our study is to utilize the sessile oak (Quercus petraea) as a climate indicator tree species to investigate potential future distribution and estimate changes in growth trends. For future spatial distribution, we used the Fuzzy membership distribution model in a new Decision Support System (DSS) which was developed for the Hungarian forestry and agricultural sectors. Through study techniques we can employ DSS, which contains various environmental layers (topography, vegetation, past and projected future climate, soils, and hydrology), to create probability distribution maps. The results, based on 12 regional climate model simulations (www.ensembles-eu.org), show that the area of sessile oak forests is shrinking continuously and will continue to do so to the end of the 21st century. For future production estimations, we analysed intensive long-term growth monitoring network plots that were established in

  16. The response of epiphytes to anthropogenic disturbance of pine-oak forests in the highlands of Chiapas, Mexico

    NARCIS (Netherlands)

    Wolf, J.H.D.

    2005-01-01

    Epiphytes contribute up to over 30% of the vascular plant diversity of old-growth tropical rain forests, but little is known about their occurrence in exploited forests that are structurally altered. Here, I estimate epiphyte species richness and biomass on 35 oak host trees, equally divided over

  17. Does fire affect amphibians and reptiles in eastern U.S. oak forests?

    Science.gov (United States)

    Rochelle B. Renken

    2006-01-01

    Current information about the effect of fire on amphibians and reptiles in oak forests of the Eastern and Central United States is reviewed. Current data suggest that fire results in little direct mortality of amphibians and reptiles. Fire has no effect on overall amphibian abundance, diversity, and number of species in comparisons of burned and unburned plots, though...

  18. The macrofungal diversity and community of Atlantic oak (Quercus petraea and Q. robur) forests in Ireland

    OpenAIRE

    Harrington, Thomas J.; O’Hanlon, Richard

    2012-01-01

    The oak species Quercus petraea and Q. Robur are dominant canopy tree species of native deciduous forests in Ireland and coastal regions of Western Europe. These forests are typically plant species-rich, and can also have a rich fungal flora. This survey examined macrofungi found in five native oak sites across Ireland over three years. Overall, 94 macrofungal species belonging to 39 genera were discovered with Mycena, Lactarius, Russula and Cortinarius the most species-rich genera. The speci...

  19. 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.

  20. How does vegetation structure influence woodpeckers and secondary cavity nesting birds in African cork oak forest?

    Science.gov (United States)

    Segura, Amalia

    2017-08-01

    The Great Spotted Woodpecker provides important information about the status of a forest in terms of structure and age. As a primary cavity creator, it provides small-medium size cavities for passerines. However, despite its interest as an ecosystem engineer, studies of this species in Africa are scarce. Here, spatially explicit predictive models were used to investigate how forest structural variables are related to both the Great Spotted Woodpecker and secondary cavity nesting birds in Maamora cork oak forest (northwest Morocco). A positive association between Great Spotted Woodpecker and both dead-tree density and large mature trees (>60 cm dbh) was found. This study area, Maamora, has an old-growth forest structure incorporating a broad range of size and condition of live and dead trees, favouring Great Spotted Woodpecker by providing high availability of foraging and excavating sites. Secondary cavity nesting birds, represented by Great Tit, African Blue Tit, and Hoopoe, were predicted by Great Spotted Woodpecker detections. The findings suggest that the conservation of the Maamora cork oak forest could be key to maintaining these hole-nesting birds. However, this forest is threatened by forestry practises and livestock overgrazing and the challenge is therefore to find sustainable management strategies that ensure conservation while allowing its exploitation.

  1. The supply and demand situation for oak timber

    Science.gov (United States)

    Kenneth L. Quigley

    1971-01-01

    Twenty oak species in the eastern United States account for one-third of the hardwood sawtimber volume and almost 10 percent of both hardwood and softwood growing-stock volume. The oak-hickory and oak-pine forest types occupy about 38 percent of the forest land in the eastern United States. Oak timber volume is increasing. Annual growth exceeds annual removals by about...

  2. Resource use and efficiency, and stomatal responses to environmental drivers of oak and pine species in an Atlantic Coastal Plain forest

    Directory of Open Access Journals (Sweden)

    Heidi J Renninger

    2015-05-01

    Full Text Available Pine-oak ecosystems are globally distributed even though differences in anatomy and leaf habit between many co-occurring oaks and pines suggest different strategies for resource use, efficiency and stomatal behavior. The New Jersey Pinelands contain sandy soils with low water- and nutrient-holding capacity providing an opportunity to examine trade-offs in resource uptake and efficiency. Therefore, we compared resource use in terms of transpiration rates and leaf nitrogen content and resource-use efficiency including water-use efficiency (WUE via gas exchange and leaf carbon isotopes and photosynthetic nitrogen-use efficiency (PNUE between oaks (Quercus alba, Q. prinus, Q. velutina and pines (Pinus rigida, P. echinata. We also determined environmental drivers (vapor pressure deficit (VPD, soil moisture, solar radiation of canopy stomatal conductance (GS estimated via sap flow and stomatal sensitivity to light and soil moisture. Net assimilation rates were similar between genera, but oak leaves used about 10% more water and pine foliage contained about 20% more N per unit leaf area. Therefore, oaks exhibited greater PNUE while pines had higher WUE based on gas exchange, although WUE from carbon isotopes was not significantly different. For the environmental drivers of GS, oaks had about 10% lower stomatal sensitivity to VPD normalized by reference stomatal conductance compared with pines. Pines exhibited a significant positive relationship between shallow soil moisture and GS, but only GS in Q. velutina was positively related to soil moisture. In contrast, stomatal sensitivity to VPD was significantly related to solar radiation in all oak species but only pines at one site. Therefore, oaks rely more heavily on groundwater resources but have lower WUE, while pines have larger leaf areas and nitrogen acquisition but lower PNUE demonstrating a trade-off between using water and nitrogen efficiently in a resource-limited ecosystem.

  3. Resource use and efficiency, and stomatal responses to environmental drivers of oak and pine species in an Atlantic Coastal Plain forest.

    Science.gov (United States)

    Renninger, Heidi J; Carlo, Nicholas J; Clark, Kenneth L; Schäfer, Karina V R

    2015-01-01

    Pine-oak ecosystems are globally distributed even though differences in anatomy and leaf habit between many co-occurring oaks and pines suggest different strategies for resource use, efficiency and stomatal behavior. The New Jersey Pinelands contain sandy soils with low water- and nutrient-holding capacity providing an opportunity to examine trade-offs in resource uptake and efficiency. Therefore, we compared resource use in terms of transpiration rates and leaf nitrogen content and resource-use efficiency including water-use efficiency (WUE) via gas exchange and leaf carbon isotopes and photosynthetic nitrogen-use efficiency (PNUE) between oaks (Quercus alba, Q. prinus, Q. velutina) and pines (Pinus rigida, P. echinata). We also determined environmental drivers [vapor pressure deficit (VPD), soil moisture, solar radiation] of canopy stomatal conductance (GS) estimated via sap flow and stomatal sensitivity to light and soil moisture. Net assimilation rates were similar between genera, but oak leaves used about 10% more water and pine foliage contained about 20% more N per unit leaf area. Therefore, oaks exhibited greater PNUE while pines had higher WUE based on gas exchange, although WUE from carbon isotopes was not significantly different. For the environmental drivers of GS, oaks had about 10% lower stomatal sensitivity to VPD normalized by reference stomatal conductance compared with pines. Pines exhibited a significant positive relationship between shallow soil moisture and GS, but only GS in Q. velutina was positively related to soil moisture. In contrast, stomatal sensitivity to VPD was significantly related to solar radiation in all oak species but only pines at one site. Therefore, oaks rely more heavily on groundwater resources but have lower WUE, while pines have larger leaf areas and nitrogen acquisition but lower PNUE demonstrating a trade-off between using water and nitrogen efficiently in a resource-limited ecosystem.

  4. 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

  5. Oak Forest Responses to Episodic-Seasonal-Drought, Chronic Multi-year Precipitation Change and Acute Drought Manipulations in a Region With Deep Soils and High Precipitation

    Science.gov (United States)

    Hanson, Paul J.; Wullschleger, Stan D.; Todd, Donald E.; Auge, Robert M.; Froberg, Mats; Johnson, Dale W.

    2010-05-01

    Implications of episodic-seasonal drought (extremely dry late summers), chronic multi-year precipitation manipulations (±33 percent over 12 years) and acute drought (-100 percent over 3 years) were evaluated for the response of vegetation and biogeochemical cycles for an upland-oak forest. The Quercus-Acer forest is located in eastern Tennessee on deep acidic soils with mean annual temperatures of 14.2 °C and abundant precipitation (1352 mm y-1). The multi-year observations and chronic manipulations were conducted from 1993 through 2005 using understory throughfall collection troughs and redistribution gutters and pipes. Acute manipulations of dominant canopy trees (Quercus prinus; Liriodendron tulipifera) were conducted from 2003 through 2005 using full understory tents. Regional and severe late-summer droughts were produced reduced stand water use and photosynthetic carbon gain as expected. Likewise, seedlings and saplings exhibited reduced survival and cumulative growth reductions. Conversely, multi-year chronic increases or decreases in precipitation and associated soil water deficits did not reduce large tree basal area growth for the tree species present. The resilience of canopy trees to chronic-change was the result of a disconnect between carbon allocation to tree growth (an early-season phenomenon) and late-season drought occurrence. Acute precipitation exclusion from the largest canopy trees also produced limited physiological responses and minimal cumulative growth reductions. Lateral root water sources were removed through trenching and could not explain the lack of response to extreme soil drying. Therefore, deep rooting the primary mechanism for large-tree resilience to severe drought. Extensive trench-based assessments of rooting depth suggested that ‘deep' water supplies were being obtained from limited numbers of deep fine roots. Observations of carbon stocks in organic horizons demonstrated accumulation with precipitation reductions and

  6. 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.

  7. Comparison of seasonal variations of ozone exposure and fluxes in a Mediterranean Holm oak forest between the exceptionally dry 2003 and the following year

    International Nuclear Information System (INIS)

    Gerosa, Giacomo; Finco, Angelo; Mereu, Simone; Vitale, Marcello; Manes, Fausto; Denti, Antonio Ballarin

    2009-01-01

    Ozone and energy fluxes have been measured using the eddy covariance technique, from June to December 2004 in Castelporziano near Rome (Italy), and compared to similar measurements made in the previous year. The studied ecosystem consisted in a typical Mediterranean Holm oak forest. Stomatal fluxes have been calculated using the resistance analogy and by inverting the Penmann-Monteith equation. Results showed that the average stomatal contribution accounts for 42.6% of the total fluxes. Non-stomatal deposition proved to be enhanced by increasing leaf wetness and air humidity during the autumnal months. From a comparison of the two years, it can be inferred that water supply is the most important limiting factor for ozone uptake and that prolonged droughts alter significantly the stomatal conductance, even 2 months after the soil water content is replenished. Ozone exposure, expressed as AOT40, behaves similarly to the cumulated stomatal flux in dry conditions whereas a different behaviour for the two indices appears in wet autumnal conditions. A difference also occurs between the two years. - Ozone fluxes to a Holm oak coastal forest show inter-annual variations depending on meteorological conditions and water availability.

  8. 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.

  9. Macromycetes of oak-lime-hornbeam woods in the Niepołomice Forest near Kraków (S Poland - monitoring studies

    Directory of Open Access Journals (Sweden)

    Władysława Wojewoda

    2014-08-01

    Full Text Available In the years 1994-1996 studies on macromycetes of the Niepołomice Forest near Kraków were made in four plots designated in deciduous forests (Tilio-Carpinetum stachyetosum with a population of Carpinus betulus, Quercus robur and Tilia cordata (the size of each plot was 1000 m2. The observations were made through an international project "Mycological monitoring in European oak forests". As many as 274 species were recorded, including 234 saprobic, 33 mycorrhizal, and 7 parasitic fungi. Moreover, 15 species of fungi are connected with oak, 24 species of fungi are threatened, and 16 species are new to Poland.

  10. A dendrochronological analysis of a disturbance-succession model for oak-pine forests of the Appalachian Mountains, USA

    Science.gov (United States)

    Patrick H. Brose; Thomas A. Waldrop

    2010-01-01

    Disturbance-succession models describe the relationship between the disturbance regime and the dominant tree species of a forest type. Such models are useful tools in ecosystem management and restoration, provided they are accurate. We tested a disturbance-succession model for the oak-pine (Quercus spp. - Pinus spp.) forests of the...

  11. Final report on the Background Soil Characterization Project at the Oak Ridge Reservation, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1993-10-01

    The Background Soil Characterization Project (BSCP) will provide background concentration levels of selected metals organic compounds, and radionuclides in soils from uncontaminated on-site areas at the Oak Ridge Reservation (ORR), and off-site in the western part of Roane County and the eastern part of Anderson County. The BSCP will establish a database, recommend how to use the data for contaminated site assessment, and provide estimates of the potential human health and environmental risks associated with the background level concentrations of potentially hazardous constituents. This volume contains the data from the Background Soil Characterization Project. When available, the following validation qualifiers are used in the appendixes. When validation qualifiers are not available, the corresponding contract laboratory data qualifiers appearing on the next page are used

  12. Soil sampling and analysis plan for the Bear Creek Valley Floodplain at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-03-01

    This Sampling and Analysis Plan (SAP) for the Bear Creek Valley (BCV) Floodplain presents the approach and rationale for characterizing potentially contaminated soils and sediments of the Bear Creek floodplain and the impact of any contaminants on the floodplain ecosystem. In addition to this SAP, the Remedial Investigation Work Plan for Bear Creek (Y02-S600) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee (ES/ER-19&D2) presents background information pertaining to this floodplain investigation.

  13. Soil sampling and analysis plan for the Bear Creek Valley Floodplain at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1995-03-01

    This Sampling and Analysis Plan (SAP) for the Bear Creek Valley (BCV) Floodplain presents the approach and rationale for characterizing potentially contaminated soils and sediments of the Bear Creek floodplain and the impact of any contaminants on the floodplain ecosystem. In addition to this SAP, the Remedial Investigation Work Plan for Bear Creek (Y02-S600) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee (ES/ER-19 ampersand D2) presents background information pertaining to this floodplain investigation

  14. 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...

  15. Influences of recovery from wildfire and thinning on soil respiration of a Mediterranean mixed forest.

    Science.gov (United States)

    López-Serrano, F R; Rubio, E; Dadi, T; Moya, D; Andrés-Abellán, M; García-Morote, F A; Miettinen, H; Martínez-García, E

    2016-12-15

    The ecosystem recovery after wildfire and thinning practices are both key processes that have great potential to influence fluxes and storage of carbon within Mediterranean semiarid ecosystems. In this study, started 7years after a wildfire, soil respiration (SR) patterns measured from 2008 to 2010 were compared between an unmanaged-undisturbed mature forest stand (UB site) and a naturally regenerated post-wildfire stand (B site) in a Mediterranean mixed forest in Spain. The disturbed stand included a control zone (unthinned forest, BUT site) and a thinned zone (BT site). Our results indicated that SR was lower at naturally regenerated after fire sites (BUT and BT) than at unburnt one. Soil under the canopy layer of pine and oak trees exhibited higher SR rates than bare or herbaceous layer soils, regardless of the site. The effect of thinning was only manifest, with a significant increase of SR, during the 1st year after thinning practices. SR showed a clear soil temperature-dependent seasonal pattern, which was strongly modulated by soil water content (SWC), especially in summer. Site-specific polynomial regression models were defined to describe SR responses, being mainly controlled by both soil temperature (Ts) and SWC at UB site, or Ts at burnt sites. The sensitivity of SR rate to Ts variations (Q 10 ) ranged between 0.20 and 6.89, with mean annual values varying between 0.92 and 1.35. Q 10 values were higher at BT than at UB-BUT sites. The results revealed a significant, non-linear dependence, of Q 10 on both Ts and SWC at UB site, and on Ts at both burnt sites. This study contributes to (i) improve the understanding of how natural recovery and management practices affect soil respiration in a Mediterranean forest during their early stages after fire disturbance and (ii) highlight the importance of Q 10 values <1 which emphasizes drought stress effect on SR temperature sensitivity. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Sympatric parallel diversification of major oak clades in the Americas and the origins of Mexican species diversity.

    Science.gov (United States)

    Hipp, Andrew L; Manos, Paul S; González-Rodríguez, Antonio; Hahn, Marlene; Kaproth, Matthew; McVay, John D; Avalos, Susana Valencia; Cavender-Bares, Jeannine

    2018-01-01

    Oaks (Quercus, Fagaceae) are the dominant tree genus of North America in species number and biomass, and Mexico is a global center of oak diversity. Understanding the origins of oak diversity is key to understanding biodiversity of northern temperate forests. A phylogenetic study of biogeography, niche evolution and diversification patterns in Quercus was performed using 300 samples, 146 species. Next-generation sequencing data were generated using the restriction-site associated DNA (RAD-seq) method. A time-calibrated maximum likelihood phylogeny was inferred and analyzed with bioclimatic, soils, and leaf habit data to reconstruct the biogeographic and evolutionary history of the American oaks. Our highly resolved phylogeny demonstrates sympatric parallel diversification in climatic niche, leaf habit, and diversification rates. The two major American oak clades arose in what is now the boreal zone and radiated, in parallel, from eastern North America into Mexico and Central America. Oaks adapted rapidly to niche transitions. The Mexican oaks are particularly numerous, not because Mexico is a center of origin, but because of high rates of lineage diversification associated with high rates of evolution along moisture gradients and between the evergreen and deciduous leaf habits. Sympatric parallel diversification in the oaks has shaped the diversity of North American forests. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.

  17. Forest meteorology research within the Oak Ridge site, eastern deciduous forest biome, USIBP

    International Nuclear Information System (INIS)

    Hutchison, B.A.; Matt, D.R.

    1977-01-01

    The data presented here indicate that the diurnal trends in forest microclimate are dominated by the diurnal trend in incident solar radiation amounts and the diurnal changes in solar elevations. Absolute values of these microclimatic variables, on the other hand, reflect strongly, the synoptic climatic conditions present and, to a lesser degree, the interactions among synoptic climatic parameters, forest structure, forest physiology, and soil moisture conditions. The seasonal changes in forest microclimate are the result of changes in incident radiation amounts, earth-sun geometry, and phenological change in forest structure along with seasonal changes in synoptic climatic parameters. The temporal and spatial variations of solar radiation within and above a deciduous forest composed predominately of tulip poplar (biriodendron tulipifera) were documented and on attempt was made to relate the variations to forest structure

  18. Long-term effects of climate change on carbon storage and tree species composition in a dry deciduous forest.

    Science.gov (United States)

    Fekete, István; Lajtha, Kate; Kotroczó, Zsolt; Várbíró, Gábor; Varga, Csaba; Tóth, János Attila; Demeter, Ibolya; Veperdi, Gábor; Berki, Imre

    2017-08-01

    Forest vegetation and soils have been suggested as potentially important sinks for carbon (C) with appropriate management and thus are implicated as effective tools in stabilizing climate even with increasing anthropogenic release of CO 2 . Drought, however, which is often predicted to increase in models of future climate change, may limit net primary productio (NPP) of dry forest types, with unknown effects on soil C storage. We studied C dynamics of a deciduous temperate forest of Hungary that has been subject to significant decreases in precipitation and increases in temperature in recent decades. We resampled plots that were established in 1972 and repeated the full C inventory by analyzing more than 4 decades of data on the number of living trees, biomass of trees and shrubs, and soil C content. Our analyses show that the decline in number and biomass of oaks started around the end of the 1970s with a 71% reduction in the number of sessile oak stems by 2014. Projected growth in this forest, based on the yield table's data for Hungary, was 4.6 kg C/m 2 . Although new species emerged, this new growth and small increases in oak biomass resulted in only 1.9 kg C/m 2 increase over 41 years. The death of oaks increased inputs of coarse woody debris to the surface of the soil, much of which is still identifiable, and caused an increase of 15.5%, or 2.6 kg C/m 2 , in the top 1 m of soil. Stability of this fresh organic matter input to surface soil is unknown, but is likely to be low based on the results of a colocated woody litter decomposition study. The effects of a warmer and drier climate on the C balance of forests in this region will be felt for decades to come as woody litter inputs decay, and forest growth remains impeded. © 2017 John Wiley & Sons Ltd.

  19. Sudden Oak Death in redwood forests: vegetation dynamics in the wake of tanoak decline

    Science.gov (United States)

    Benjamin Ramage; Kevin O’Hara

    2010-01-01

    Numerous lines of inquiry have concluded that tanoak (Lithocarpus densiflorus) will continue to experience drastic population declines and may even disappear entirely from redwood (Sequoia sempervirens) forests as a result of the exotic disease sudden oak death (SOD) (Maloney and others 2005, McPherson and others 2005,...

  20. Imprint of oaks on nitrogen availability and δ15N in California grassland-savanna: A case of enhanced N inputs?

    Science.gov (United States)

    Perakis, S.S.; Kellogg, C.H.

    2007-01-01

    Woody vegetation is distributed patchily in many arid and semi-arid ecosystems, where it is often associated with elevated nitrogen (N) pools and availability in islands of fertility. We measured N availability and δ15N in paired blue-oak versus annual grass dominated patches to characterize the causes and consequences of spatial variation in N dynamics of grassland-savanna in Sequoia-Kings Canyon National Park. We found significantly greater surface soil N pools (0–20 cm) in oak patches compared to adjacent grass areas across a 700 m elevation gradient from foothills to the savanna-forest boundary. N accumulation under oaks was associated with a 0.6‰ depletion in soil δ15N relative to grass patches. Results from a simple δ15N mass balance simulation model, constrained by surface soil N and δ15N measured in the field, suggest that the development of islands of N fertility under oaks can be traced primarily to enhanced N inputs. Net N mineralization and percent nitrification in laboratory incubations were consistently higher under oaks across a range of experimental soil moisture regimes, suggesting a scenario whereby greater N inputs to oak patches result in net N accumulation and enhanced N cycling, with a potential for greater nitrate loss as well. N concentrations of three common herbaceous annual plants were nearly 50% greater under oak than in adjacent grass patches, with community composition shifted towards more N-demanding species under oaks. We find that oaks imprint distinct N-rich islands of fertility that foster local feedback between soil N cycling, plant N uptake, and herbaceous community composition. Such patch-scale differences in N inputs and plant–soil interactions increase biogeochemical heterogeneity in grassland-savanna ecosystems and may shape watershed-level responses to chronic N deposition.

  1. 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.

  2. Using aerial photography to estimate wood suitable for charcoal in managed oak forests

    Science.gov (United States)

    Ramírez-Mejía, D.; Gómez-Tagle, A.; Ghilardi, A.

    2018-02-01

    Mexican oak forests (genus Quercus) are frequently used for traditional charcoal production. Appropriate management programs are needed to ensure their long-term use, while conserving the biodiversity and ecosystem services, and associated benefits. A key variable needed to design these programs is the spatial distribution of standing woody biomass. A state-of-the-art methodology using small format aerial photographs was developed to estimate the total aboveground biomass (AGB) and aboveground woody biomass suitable for charcoal making (WSC) in intensively managed oak forests. We used tree crown area (CAap) measurements from very high-resolution (30 cm) orthorectified small format digital aerial photographs as the predictive variable. The CAap accuracy was validated using field measurements of the crown area (CAf). Allometric relationships between: (a) CAap versus AGB, and (b) CAap versus WSC had a high significance level (R 2 > 0.91, p < 0.0001). This approach shows that it is possible to obtain sound biomass estimates as a function of the crown area derived from digital small format aerial photographs.

  3. Restoration of Black Oak (Quercus velutina) Sand Barrens via Three Different Habitat Management Approaches

    Science.gov (United States)

    Kriska, David John

    Disturbance regimes, i.e. frequent fires, historically maintained oak barrens until European settlement patterns, and eventually, Smoky the Bear and the fire suppression campaign of the U.S. Forest Service snuffed out the periodic flames. In the absence of a disturbance regime, ground layer floral composition at many historical oak sand barrens will change predominantly because of a buildup of leaf litter and shading of the soils. Termed mesophication, this process of ecological succession will drive Black Oak Sand Barrens to an alternate steady state. A survey conducted on Singer Lake Bog in Green, Ohio, demonstrated that succession shifted the community to red maple-black cherry woodlands more typical of a dry southern forest. In an attempt to revive disturbance, three restoration techniques were applied at ten degraded northeast Ohio oak barrens to contrast their effectiveness in restoring black oak sand barren flora. The three restoration treatments were select canopy tree reduction favoring 5% to 30% tree canopy cover, forest floor leaf litter removal, and prescribed fire. Vegetation responses to manipulations were monitored prior to and following treatment applications, and were compared against both baseline data from before-treatment surveys and paired control sites adjacent treated areas. Imposing disturbance successfully increased species diversity and abundance above that found across Singer Lake Bog compared to sampling made prior to and adjacent to treated areas. Select canopy tree removal exhibited the largest floral responses from targeted barrens species, i.e. graminoids. A forest floor invertebrate family (Carabidea: Coleoptera) was measured for species richness and abundance pre and post treatment, where a noticeable shift occurred away from woodland obligate ground beetles toward open grassland species. Replicating oak barren structure, prior to replicating disturbance processes, is the first step in the ecological restoration of these systems.

  4. Nutrient cycling and nutrient losses in Andean montane forests from Antioquia, Colombia

    International Nuclear Information System (INIS)

    Londono Alvarez, Adriana; Montoya Gomez, Diana Cristina; Leon Pelaez, Juan Diego; Gonzalez Hernandez, Maria Isabel

    2007-01-01

    Gravitational flow and its chemical composition were measured in montane oak forests (Quercus humboldtii), in pine (Pinus patula) and cypress (Cupressus lusitanica) plantations in Piedras Blancas, Antioquia (Colombia), over two years. Zero tension lysimeters were used at different depth soil levels, the highest gravitational flow value at highest depth (50-80 cm) was obtained in cypress plot (492-7 mm), followed by pine (14,2 mm) and oak forest (2,0 mm). A similar behavior was encountered for nutrient losses, following the same pattern as gravitational flow. thus, for oak, pine and cypress, nutrient losses were respective/y: ca: 0,004, 0,084 and 2,270 kg ha -1 Y 1 ; P 0,008, 0,052 and 1,234 kg ha -1 Y 1 , mg: 0,004, 0,022 and 0,667 kg ha -1 y 1. K losses were 0,08 and 7,092 kg ha -1 Y 1 for oak forest and cypress plantation respectively. Nutrient losses followed the next order for each type of forest: oak: K ≥ P ≥Ca≥Mg, pine: Ca≥Fe≥P>Mg≥Zn≥Mn and cypress: K≥Mn≥Ca≥P≥Fe≥Zn≥Mg

  5. 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.

  6. Heavy metal pollution and forest health in the Ukrainian Carpathians

    International Nuclear Information System (INIS)

    Shparyk, Y.S.; Parpan, V.I.

    2004-01-01

    The Ukrainian Carpathians are characterized by high air pollution caused by emissions from numerous industries. We have been monitoring the state of forests in this region since 1989. The highest levels of tree defoliation (>30%) are found close to industrial emission sources and in the upper mountain forests of the Ivano-Frankivsk and Chernivtsi regions. This is caused by a combination of strong anthropogenic influences (pollution, illegal uses, recreation) as well as poor site and climatic conditions. In the Ivano-Frankivsk region, Cd and Mo accumulate in forest soils; Cr, Mo and Zn soil concentrations are higher than their limit levels; and Pb concentrations exceed toxic levels close to industrial areas (10% of the region territory). Local background levels of heavy metals are greatly exceeded in snow close to industrial regions. Analysis of correlation matrices shows that the chemical elements Ba, Cd, Co, Cr, Cu, Mo, Ni, Pb, V and Zn occur at pollution levels in natural ecosystems in the Ukrainian Carpathians. Maximum concentrations of toxic elements occur in the oak forest zone; the most industrially developed area of the region. Toxic heavy metals in the Ukrainian Carpathians forests enter with precipitation and dustfall, then become fixed in soil and accumulate in leaves, needles of vascular plants and mosses. Concentrations of these metals decrease with altitude: highest in the oak forests, less in beech, and lowest in the spruce forest zones. However, some chemical elements have the highest concentrations in spruce forests; V in needles, As in snow, and Ba and Al in soils. - Local industrial emissions of heavy metal pollution and the condition of Ukrainian Carpathians forests are examined

  7. Long-term variability and environmental control of the carbon cycle in an oak-dominated temperate forest

    Science.gov (United States)

    Jing Xie; Jiquan Chen; Ge Sun; Housen Chu; Asko Noormets; Zutao Ouyang; Ranjeet John; Shiqiang Wan; Wenbin Guan

    2014-01-01

    Our understanding of the long-term carbon (C) cycle of temperate deciduous forests and its sensitivity to climate variability is limited due to the large temporal dynamics of C fluxes. The goal of the study was to quantify the effects of environmental variables on the C balance in a 70-year-old mixed-oak woodland forest over a 7-year period in northwest Ohio, USA. The...

  8. Disking and mid- and understory removal following an above-average acorn crop in three mature oak forests in southern Indiana

    Science.gov (United States)

    Ronald A. Rathfon; Nathanael I. Lichti; Robert K. Swihart

    2008-01-01

    We disked using small-scale equipment in the understory of three mature upland oak (Quercus) forests in southern Indiana immediately following acorn dispersal in an aboveaverage seed crop year as a means of improving oak seedling establishment. Three different mid- and understory removal treatments were also applied to create favorable light...

  9. Influence of oak planting on microelement composition (on example of Mn) of ordinary chernozem

    OpenAIRE

    Y. O. Tagunova

    2011-01-01

    Changes of Mn content in the ordinary chernozem of the forb-fescue-stipa steppeunder the influence of oak afforestation within the Prisamar’ya Dniprovske region were studied. The increase of the Mn content in the soil under the artificial oak plantation was noted. The average gross content of Mn in the root layer of the chernozem improved by forest was 541.2 mg/kg and 139.2 mg/kg in the ordinary chernozem. Average content of potentially available metal (mobile forms) in the root layer is 0.5 ...

  10. [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.

  11. Ozone risk assessment in three oak species as affected by soil water availability.

    Science.gov (United States)

    Hoshika, Yasutomo; Moura, Barbara; Paoletti, Elena

    2018-03-01

    To derive ozone (O 3 ) dose-response relationships for three European oak species (Quercus ilex, Quercus pubescens, and Quercus robur) under a range of soil water availability, an experiment was carried out with 2-year-old potted seedlings exposed to three levels of water availability in the soil and three levels of O 3 pollution for one growing season in an ozone free-air controlled exposure (FACE) facility. Total biomass losses were estimated relative to a hypothetical clean air at the pre-industrial age, i.e., at 10 ppb as daily average (M24). A stomatal conductance model was parameterized with inputs from the three species for calculating the stomatal O 3 flux. Exposure-based (M24, W126, and AOT40) and flux-based (phytotoxic O 3 dose (POD) 0-3 ) dose-response relationships were estimated and critical levels (CL) were calculated for a 5% decline of total biomass. Results show that water availability can significantly affect O 3 risk assessment. In fact, dose-response relationships calculated per individual species at each water availability level resulted in very different CLs and best metrics. In a simplified approach where species were aggregated on the basis of their O 3 sensitivity, the best metric was POD 0.5 , with a CL of 6.8 mmol m -2 for the less O 3 -sensitive species Q. ilex and Q. pubescens and of 3.5 mmol m -2 for the more O 3 -sensitive species Q. robur. The performance of POD 0 , however, was very similar to that of POD 0.5 , and thus a CL of 6.9 mmol m -2 POD 0 and 3.6 mmol m -2 POD 0 for the less and more O 3 -sensitive oak species may be also recommended. These CLs can be applied to oak ecosystems at variable water availability in the soil. We conclude that POD y is able to reconcile the effects of O 3 and soil water availability on species-specific oak productivity.

  12. 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.

  13. Assessing the Cost of an Invasive Forest Pathogen: A Case Study with Oak Wilt

    Science.gov (United States)

    Haight, Robert G.; Homans, Frances R.; Horie, Tetsuya; Mehta, Shefali V.; Smith, David J.; Venette, Robert C.

    2011-03-01

    Economic assessment of damage caused by invasive alien species provides useful information to consider when determining whether management programs should be established, modified, or discontinued. We estimate the baseline economic damage from an invasive alien pathogen, Ceratocystis fagacearum, a fungus that causes oak wilt, which is a significant disease of oaks ( Quercus spp.) in the central United States. We focus on Anoka County, Minnesota, a 1,156 km2 mostly urban county in the Minneapolis-Saint Paul metropolitan region. We develop a landscape-level model of oak wilt spread that accounts for underground and overland pathogen transmission. We predict the economic damage of tree mortality from oak wilt spread in the absence of management during the period 2007-2016. Our metric of economic damage is removal cost, which is one component of the total economic loss from tree mortality. We estimate that Anoka County has 5.92 million oak trees and 885 active oak wilt pockets covering 5.47 km2 in 2007. The likelihood that landowners remove infected oaks varies by land use and ranges from 86% on developed land to 57% on forest land. Over the next decade, depending on the rates of oak wilt pocket establishment and expansion, 76-266 thousand trees will be infected with discounted removal cost of 18-60 million. Although our predictions of removal costs are substantial, they are lower bounds on the total economic loss from tree mortality because we do not estimate economic losses from reduced services and increased hazards. Our predictions suggest that there are significant economic benefits, in terms of damage reduction, from preventing new pocket establishment or slowing the radial growth of existing pockets.

  14. Remnant large 'rescue' trees enhance epiphyte resilience to anthropogenic disturbance of pine-oak forests in the Highlands of Chiapas, Mexico

    NARCIS (Netherlands)

    Wolf, J.H.D.

    2006-01-01

    I studied vascular epiphytes in 16 pine-oak forest fragments within an 400 km2 relatively flat area at c. 2300 m elevation on an extended gradient of anthropogenic disturbance. Epiphyte biomass and species richness on 35 oak host trees in six diameter classes varied between the sites from 0.8 to 243

  15. Forecasting oak decline caused by Phytophthora cinnamomi in Andalusia: Identification of priority areas for intervention

    NARCIS (Netherlands)

    Duque Lazo, Joaquin; Navarro-Cerrillo, Rafael Maria; Van Gils, Hein; Groen, T.A.

    2018-01-01

    Since the mid-20th century, trees in the Andalusian oak dehesa and forests have exhibited stress that often ends in the death of the tree. These events have been associated with Phytophthora cinnamomi, a soil-borne root pathogen, which causes root rot, bark cankers, decay and mortality – known as

  16. The role of forest in runoff generation in a suburban catchment

    Science.gov (United States)

    Ferreira, C. S. S.; Soares, D.; Soares, A. J. D.; Coelho, C. O. A.; Steenhuis, T. S.; Keizer, J. J.; Walsh, R. P. D.

    2012-04-01

    Forests play an important role in the water cycle, particularly through their influence on infiltration and evapotranspiration processes. Removing forest for urban growth will affect the hydrological cycle, but to what degree is not known. To improve the knowledge about the role of forest areas in the catchment surface runoff, a total of nine runoff plots (16m2) was installed in the three predominant woodland types found in the small Ribeira dos Covões catchment (620ha), located in a rapid urbanizing area in central Portugal. The three representative study sites comprised: (i) a dense eucalyptus stand on a sandy-loam soil overlying sandstone; (ii) a open eucalyptus stand dominated by dense shrub vegetation, also on a sandy-loam soil overlying sandstone; (iii) a Mediterranean oak stand on a loamy soil overlying limestone. The three plots at each site were bounded by metal sheets and their outlets were connected to a modified Gerlach through for sediments retention and, subsequently, a tipping-bucket device and a tank for recording and collecting the runoff. The overland flow generated by the plots was monitored for almost one year. In addition, soil moisture content was measured automatically at 0-2, 5-10 and 15-20cm soil depth using 5 sensors per plot. Furthermore, soil water repellency was repeatedly measured on the field, through ethanol percentage method. In the dense eucalyptus forest the soil is hydrophobic during most of the year, just vanished after severe rainfall events. This reflects on low soil moisture content that reached 37% during wet periods. In this area, with an average slope of 20°±5°, the runoff coefficient ranged between 0.0% (for a 3mm rainfall event) and 2.2% (for a 23mm rainfall during hydrophobic conditions). In general, the runoff was higher when the soil was extremely repellent, but it also increased with soil moisture rise when the repellence was absent (reaching 0.6%). In the open eucalyptus forest, hydrophobicity is also presented

  17. Throughfall-mediated alterations to soil microbial community structure in a forest plot of homogenous soil texture, litter, and plant species composition

    Science.gov (United States)

    Van Stan, John; Rosier, Carl; Moore, Leslie; Gay, Trent; Reichard, James; Wu, Tiehang; Kan, Jinjun

    2015-04-01

    Identifying spatiotemporal influences on soil microbial community (SMC) structure is critical to our understanding of patterns in biogeochemical cycling and related ecological services (e.g., plant community structure, water quality, response to environmental change). Since forest canopy structure alters the spatiotemporal patterning of precipitation water and solute supplies to soils (via "throughfall"), is it possible that changes in SMC structure could arise from modifications in canopy elements? Our study investigates this question by monitoring throughfall water and dissolved ion supply to soils beneath a continuum of canopy structure: from large gaps (0% cover), to bare Quercus virginiana Mill. (southern live oak) canopy (~50-70%), to heavy Tillandsia usneoides L. (Spanish moss) canopy (>90% cover). Throughfall water supply diminished with increasing canopy cover, yet increased washoff/leaching of Na+, Cl-, PO43-, and SO42- from the canopy to the soils. Presence of T. usneoides diminished throughfall NO3-, but enhanced NH4+, concentrations supplied to subcanopy soils. The mineral soil horizon (0-10 cm) sampled in triplicate from locations receiving throughfall water and solutes from canopy gaps, bare canopy, and T. usneoides-laden canopy significantly differed in soil chemistry parameters (pH, Ca2+, Mg2+, CEC). Polymerase Chain Reaction-Denaturant Gradient Gel Electrophoresis (PCR-DGGE) banding patterns beneath similar canopy covers (experiencing similar throughfall dynamics) also produced high similarities per ANalyses Of SIMilarity (ANO-SIM), and clustered together when analyzed by Nonmetric Multidimensional Scaling (NMDS). These results suggest that modifications of forest canopy structures are capable of affecting mineral-soil horizon SMC structure via throughfall when canopies' biomass distribution is highly heterogeneous. As SMC structure, in many instances, relates to functional diversity, we suggest that future research seek to identify functional

  18. 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)

  19. Traditional silvopastoral management and its effects on forest stand structure in northern Zagros, Iran

    DEFF Research Database (Denmark)

    Valipour, Ahmad; Plieninger, Tobias; Shakeri, Zahed

    2014-01-01

    and to investigate the effects of these practices on forest stand structure. To understand how the traditional forest management system works, empirical survey methods, in particular face to face interviews and participation in traditional practices have been employed. In general, local livelihoods depend on three......Oak forests of Iran are managed for soil conservation, water quality and other non-market ecosystem services. Nationalization policies in 1963 implied shifts from private ownership and informal traditional management to public ownership and state forest management. In spite of the nationalization......, informal practices and conventional ownership have been continued which has caused considerable conflicts between local people and the state forest administration. The aim of the study was to systematically gather the components of traditional silvopastoral management in these oak forests...

  20. Nitrogen Effects on Organic Dynamics and Soil Communities in Forest and Agricultural Systems

    Science.gov (United States)

    Grandy, S.; Neff, J.; Sinsabaugh, B.; Wickings, K.

    2008-12-01

    Human activities have doubled the global flux of biologically available N to terrestrial ecosystems but the effects of N on soil organic matter dynamics and soil communities remain difficult to predict. We examined soil organic matter chemistry and enzyme kinetics in three soil fractions (>250, 63-250, and pyrolysis-gas chromatography/mass spectroscopy, we found striking, ecosystem-specific effects of N deposition on carbohydrate abundance. Furfural, the dominant pyrolysis product of polysaccharides, was significantly decreased by simulated N deposition in the sugar maple/basswood system (15.87 versus 4.99%) but increased by N in the black oak/white oak system (8.83 versus 24.01%). There were ca. 3-fold increases in the ratio of total lignin derivatives to total polysaccharides in the >250 μm fraction of the sugar maple/basswood system but there were no changes in other size classes or in the black oak/white oak system. We also measured significant increases in the ratio of lignin derivatives to N-bearing compounds in the 63-250 and >250 μm fractions in both ecosystems but not in the corn-based cropping system. Our results demonstrate that changes in soil organic matter chemistry resulting from atmospheric N deposition or fertilization are directly linked to variation in enzyme responses to increased N availability across ecosystems and soil size fractions.

  1. Impacts of Phytophthora ramorum on oaks and tanoaks in Marin County, California forests since 2000

    Science.gov (United States)

    Brice A. McPherson; David L. Wood; Maggi Kelly; Sylvia R. Mori; Pavel Svihra; Andrew J. Storer; Richard B. Standiford

    2010-01-01

    The forests of Marin County were among the first in coastal California to be affected by the Phytophthora ramorum epidemic. Although initially observed in 1994 in tanoaks (Lithocarpus densiflorus) and 1995 in coast live oaks (Quercus agrifolia), it is evident from studies of disease progression that the...

  2. Canopy structural alterations to nitrogen functions of the soil microbial community in a Quercus virginiana forest

    Science.gov (United States)

    Moore, L. D.; Van Stan, J. T., II; Rosier, C. L.; Gay, T. E.; Wu, T.

    2014-12-01

    Forest canopy structure controls the timing, amount and chemical character of precipitation supply to soils through interception and drainage along crown surfaces. Yet, few studies have examined forest canopy structural connections to soil microbial communities (SMCs), and none have measured how this affects SMC N functions. The maritime Quercus virginiana Mill. (southern live oak) forests of St Catherine's Island, GA, USA provide an ideal opportunity to examine canopy structural alterations to SMCs and their functioning, as their throughfall varies substantially across space due to dense Tillandsia usneoides L. (spanish moss) mats bestrewn throughout. To examine the impact of throughfall variability on SMC N functions, we examined points along the canopy coverage continuum: large canopy gaps (0%), bare canopy (50-60%), and canopy of heavy T. usneoides coverage (>=85%). Five sites beneath each of the canopy cover types were monitored for throughfall water/ions and soil leachates chemistry for one storm each month over the growing period (7 months, Mar-2014 to Sep-2014) to compare with soil chemistry and SMC communities sampled every two months throughout that same period (Mar, May, Jul, Sep). DGGE and QPCR analysis of the N functioning genes (NFGs) to characterize the ammonia oxidizing bacterial (AOB-amoA), archaea (AOA-amoA), and ammonification (chiA) communities were used to determine the nitrification and decomposition potential of these microbial communities. PRS™-probes (Western Ag Innovations Inc., Saskatoon, Canada) were then used to determine the availability of NO3-N and NH4+N in the soils over a 6-week period to evaluate whether the differing NFG abundance and community structures resulted in altered N cycling.

  3. 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

  4. Photo guide for estimating risk to hardwood trees during prescribed burning operations in eastern oak forests

    Science.gov (United States)

    Patrick H. Brose

    2009-01-01

    A field guide of 40 photographs of common hardwood trees of eastern oak forests and fuel loadings surrounding their bases. The guide contains instructions on how to rapidly assess a tree's likelihood to be damaged or killed by prescribed burning.

  5. 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.

  6. 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...

  7. Woodland salamander responses to a shelterwood harvest-prescribed burn silvicultural treatment within Appalachian mixed-oak forests

    Science.gov (United States)

    Ford, W. Mark; Mahoney, Kathleen R.; Russell, Kevin R.; Rodrigue, Jane L.; Riddle, Jason D.; Schuler, Thomas M.; Adams, Mary Beth

    2015-01-01

    Forest management practices that mimic natural canopy disturbances, including prescribed fire and timber harvests, may reduce competition and facilitate establishment of favorable vegetative species within various ecosystems. Fire suppression in the central Appalachian region for almost a century has contributed to a transition from oak-dominated to more mesophytic, fire-intolerant forest communities. Prescribed fire coupled with timber removal is currently implemented to aid in oak regeneration and establishment but responses of woodland salamanders to this complex silvicultural system is poorly documented. The purpose of our research was to determine how woodland salamanders respond to shelterwood harvests following successive burns in a central Appalachian mixed-oak forest. Woodland salamanders were surveyed using coverboard arrays in May, July, and August–September 2011 and 2012. Surveys were conducted within fenced shelterwood-burn (prescribed fires, shelterwood harvest, and fencing to prevent white-tailed deer [Odocoileus virginianus] herbivory), shelterwood-burn (prescribed fires and shelterwood harvest), and control plots. Relative abundance was modeled in relation to habitat variables measured within treatments for mountain dusky salamanders (Desmognathus ochrophaeus), slimy salamanders (Plethodon glutinosus), and eastern red-backed salamanders (Plethodon cinereus). Mountain dusky salamander relative abundance was positively associated with canopy cover and there were significantly more individuals within controls than either shelterwood-burn or fenced shelterwood-burn treatments. Conversely, habitat variables associated with slimy salamanders and eastern red-backed salamanders did not differ among treatments. Salamander age-class structure within controls did not differ from shelterwood-burn or fenced shelterwood-burn treatments for any species. Overall, the woodland salamander assemblage remained relatively intact throughout the shelterwoodburn

  8. Fire frequency effects on fuel loadings in pine-oak forests of the Madrean Province

    Science.gov (United States)

    Francisco J. Escobedo; Peter F. Ffolliott; Gerald J. Gottfried; Florentino Garza

    2001-01-01

    Loadings of downed woody fuels in pine-oak forests of the Madrean Province are heavier on sites in southeastern Arizona with low fire frequencies and lower on sites in northeastern Sonora, Mexico, with high fire frequencies. Low fire frequencies in southeastern Arizona are attributed largely to past land uses and the fire suppression policies of land management...

  9. Determinants of total and available phosphorus in forested Alfisols and Ultisols of the Ozark Highlands, USA

    Science.gov (United States)

    Gurbir Singh; Keith W. Goyne; John M. Kabrick

    2015-01-01

    Phosphorus is an important nutrient limiting forest growth in many parts of world, and soil P forms and concentrations may be associated with a host of soil and environmental attributes in a complex soil landscape. The objective of this study was to identify key environmental and soil properties influencing total and available soil P concentrations in a mixed oak (

  10. Managing an oak decline crisis in Oakville, Ontario: lessons learned

    Science.gov (United States)

    Peter A. Williams; John W. McNeil; Kurt W. Gottschalk; Robert A. Haack

    2013-01-01

    The town of Oakville, Ontario, is located along the north shore of Lake Ontario between Toronto and Hamilton. In the fall of 2002, significant oak (Quercus spp.) mortality was observed at Oakville's Iroquois Shoreline Woods Park, an environmentally significant forest remnant noted for its oak-dominated forests. Investigations suggested that oak...

  11. 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

  12. 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

  13. Long-term persistence and fire resilience of oak shrubfields in dry conifer forests of northern New Mexico

    Science.gov (United States)

    Guiterman, Christopher H.; Margolis, Ellis; Allen, Craig D.; Falk, Donald A.; Swetnam, Thomas W.

    2017-01-01

    Extensive high-severity fires are creating large shrubfields in many dry conifer forests of the interior western USA, raising concerns about forest-to-shrub conversion. This study evaluates the role of disturbance in shrubfield formation, maintenance and succession in the Jemez Mountains, New Mexico. We compared the environmental conditions of extant Gambel oak (Quercus gambelii) shrubfields with adjoining dry conifer forests and used dendroecological methods to determine the multi-century fire history and successional dynamics of five of the largest shrubfields (76–340 ha). Across the study area, 349 shrubfields (5–368 ha) occur in similar topographic and climate settings as dry conifer forests. This suggests disturbance, rather than other biophysical factors, may explain their origins and persistence. Gambel oak ages and tree-ring fire scars in our sampled shrubfields indicate they historically (1664–1899) burned concurrently with adjoining conifer forests and have persisted for over 115 years in the absence of fire. Aerial imagery from 1935 confirmed almost no change in sampled shrubfield patch sizes or boundaries over the twentieth century. The largest shrubfield we identified is less than 4% the size of the largest conifer-depleted and substantially shrub-dominated area recently formed in the Jemez following extensive high-severity wildfires, indicating considerable departure from historical patterns and processes. Projected hotter droughts and increasingly large high-severity fires could trigger more forest-to-shrub transitions and maintain existing shrubfields, inhibiting conifer forest recovery. Restoration of surface fire regimes and associated historical forest structures likely could reduce the rate and patch size of dry conifer forests being converted to shrubfields.

  14. 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...

  15. 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...

  16. Changes in understory species occurrence of a secondary broadleaved forest after mass mortality of oak trees under deer foraging pressure

    Directory of Open Access Journals (Sweden)

    Hiroki Itô

    2016-12-01

    Full Text Available The epidemic of mass mortality of oak trees by Japanese oak wilt has affected secondary deciduous broadleaved forests that have been used as coppices in Japan. The dieback of oak trees formed gaps in the crown that would be expected to enhance the regeneration of shade-intolerant pioneer species. However, foraging by sika deer Cervus nippon has also affected forest vegetation, and the compound effects of both on forest regeneration should be considered when they simultaneously occur. A field study was conducted in Kyôto City, Japan to investigate how these compound effects affected the vegetation of the understory layer of these forests. The presence/absence of seedlings and saplings was observed for 200 quadrats sized 5 m ×5 m for each species in 1992, before the mass mortality and deer encroachment, and in 2014 after these effects. A hierarchical Bayesian model was constructed to explain the occurrence, survival, and colonization of each species with their responses to the gaps that were created, expanded, or affected by the mass mortality of Quercus serrata trees. The species that occurred most frequently in 1992, Eurya japonica, Quercus glauca, and Cleyera japonica, also had the highest survival probabilities. Deer-unpalatable species such as Symplocos prunifolia and Triadica sebifera had higher colonization rates in the gaps, while the deer-palatable species Aucuba japonica had the smallest survival probability. The gaps thus promoted the colonization of deer-unpalatable plant species such as Symplocos prunifolia and Triadica sebifera. In the future, such deer-unpalatable species may dominate gaps that were created, expanded, or affected by the mass mortality of oak trees.

  17. Soil properties in fire-consumed log burnout openings in a Missouri oak savanna

    Science.gov (United States)

    Charles C. Rhoades; A. J. Meier; A. J. Rebertus

    2004-01-01

    Downed logs are known to increase species diversity in many forest ecosystems by increasing resource and structural complexity and by altering fire behavior in fire-prone ecosystems. In a frequently burned oak savanna in central Missouri, combustion of downed logs formed patches that have remained free of herbaceous vegetation for more than 3 years. To assess the...

  18. Soil organic carbon sequestration as affected by afforestation: the Darab Kola forest (north of Iran) case study.

    Science.gov (United States)

    Kooch, Yahya; Hosseini, Seyed Mohsen; Zaccone, Claudio; Jalilvand, Hamid; Hojjati, Seyed Mohammad

    2012-09-01

    Following the ratification of the Kyoto Protocol, afforestation of formerly arable lands and/or degraded areas has been acknowledged as a land-use change contributing to the mitigation of increasing atmospheric CO(2) concentration in the atmosphere. In the present work, we study the soil organic carbon sequestration (SOCS) in 21 year old stands of maple (Acer velutinum Bioss.), oak (Quercus castaneifolia C.A. Mey.), and red pine (Pinus brutia Ten.) in the Darab Kola region, north of Iran. Soil samples were collected at four different depths (0-10, 10-20, 20-30, and 30-40 cm), and characterized with respect to bulk density, water content, electrical conductivity, pH, texture, lime content, total organic C, total N, and earthworm density and biomass. Data showed that afforested stands significantly affected soil characteristics, also raising SOCS phenomena, with values of 163.3, 120.6, and 102.1 Mg C ha(-1) for red pine, oak and maple stands, respectively, vs. 83.0 Mg C ha(-1) for the control region. Even if the dynamics of organic matter (OM) in soil is very complex and affected by several pedo-climatic factors, a stepwise regression method indicates that SOCS values in the studied area could be predicted using the following parameters, i.e., sand, clay, lime, and total N contents, and C/N ratio. In particular, although the chemical and physical stabilization capacity of organic C by soil is believed to be mainly governed by clay content, regression analysis showed a positive correlation between SOCS and sand (R = 0.86(**)), whereas a negative correlation with clay (R = -0.77(**)) was observed, thus suggesting that most of this organic C occurs as particulate OM instead of mineral-associated OM. Although the proposed models do not take into account possible changes due to natural and anthropogenic processes, they represent a simple way that could be used to evaluate and/or monitor the potential of each forest plantation in immobilizing organic C in soil (thus

  19. 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

  20. The historical significance of oak

    Science.gov (United States)

    J. V. Thirgood

    1971-01-01

    A brief history of the importance of oak in Europe, contrasting the methods used in France and Britain to propagate the species and manage the forests for continued productivity. The significance of oak as a strategic resource during the sailing-ship era is stressed, and mention is made of the early development of oak management in North America. The international...

  1. 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

  2. A contribution to the sessile oak site and beech site defining in central Serbia

    Directory of Open Access Journals (Sweden)

    Krstić Milun

    2009-01-01

    Full Text Available The study was carried out in sessile oak forests and beech forests in the region central Serbia. The stands are classified as pure stands with the percentage of other species up to 10% per tree number, mixed forests of sessile oak with other species, and mixed forests of beech with other species, whose percentage does not exceed 50%. Altogether 257 stands were monitored - 202 beech stands and 55 sessile oak stands. By the applied method of defining the local heat potential (Lujić, 1960, modified by Ratknić et al. (2001 and Krstić (2004, 2008, which represents possibility of soil heating without vegetation, were determined. In this way, a scale of 162 possible combinations of local heat potential was obtained, which explains more precisely the dependence of beech stands and sessile oak stands on the topographic conditions. By applying the weighted values of the thermal co-ordinates of aspect and slope (E for each altitudinal belt of 100 m, it was concluded that pure stands have the widest ecological range. Pure beech stands occur at the sites with 34 combinations of thermal co-ordinates E.V=4.6 to 8.12. Pure sessile oak stands occur at the sites with 12 combinations of thermal co-ordinates E.V=5.10 to 8.11. The percentage of mixed beech stands with other broadleaf species is the highest at the sites with the co-ordinate V=10-11 (at the altitudes between 700 and 900 m is about 60 %. Mixed stands of sessile oak and beech are located on the terrains with combinations of thermal co-ordinates E.V=7.9 to 8.12. By using the local heat potential of a region, it can be identified which sites, i.e. which combinations of exposure, slope and altitude belong to the particular tree species. Consequently, a more reliable selection of tree species can be done for the bio-reclamation of barrens and other deforested terrains.

  3. Oak regeneration potential increased by shelterwood treatments

    Science.gov (United States)

    Richard C. Schlesinger; Ivan L. Sander; Kenneth R. Davidson

    1993-01-01

    In much of the Central Hardwood Forest Region, oak species are not regenerating well, even though large oak trees are common within the existing forests. The shelterwood method has been suggested as a potential tool for establishing and developing advanced regeneration where it is lacking. The 10-yr results from a study of several variants of the shelterwood method...

  4. Annual report on the Background Soil Characterization Project on the Oak Ridge Reservation, Oak Ridge, Tennessee: Results of Phase 1 investigation

    International Nuclear Information System (INIS)

    Watkins, D.R.; Goddard, P.L.; Hatmaker, T.L.; Hook, L.A.; Jackson, B.L.; Kimbrough, C.W.; Lee, S.Y.; Lietzke, D.A.; McGin, C.W.; Nourse, B.D.; Schmoyer, R.L.; Shaw, R.A.; Stinnette, S.E.; Switek, J.; Wright, J.C.; Ammons, J.T.; Branson, J.L.; Burgoa, B.B.

    1993-05-01

    Many constituents of potential concern for human health occur naturally at low concentrations in undisturbed soils. The Background soil Characterization Project (BSCP) was undertaken to provide background concentration data on potential contaminants in natural soils on the Oak Ridge Reservation (ORR). The objectives of the BSCP are to provide baseline data for contaminated site assessment and estimates of potential human health risk associated with background concentrations of hazardous and other constituents in native soils. This report presents, evaluates, and documents data and results obtained in Phase I of the project. It is intended to be a stand-alone document for application and use in structuring and conducting remedial investigation and remedial action projects in the Environmental Restoration (ER) Program

  5. Annual report on the Background Soil Characterization Project on the Oak Ridge Reservation, Oak Ridge, Tennessee: Results of Phase 1 investigation

    Energy Technology Data Exchange (ETDEWEB)

    Watkins, D.R.; Goddard, P.L.; Hatmaker, T.L.; Hook, L.A.; Jackson, B.L.; Kimbrough, C.W.; Lee, S.Y.; Lietzke, D.A.; McGin, C.W.; Nourse, B.D.; Schmoyer, R.L.; Shaw, R.A.; Stinnette, S.E.; Switek, J.; Wright, J.C. [Oak Ridge National Lab., TN (United States); Ammons, J.T.; Branson, J.L.; Burgoa, B.B. [Tennessee Univ., Knoxville, TN (United States). Dept. of Plant and Soil Science; Lietzke, D.A. [Lietzke (David A.), Rutledge, TN (United States)

    1993-05-01

    Many constituents of potential concern for human health occur naturally at low concentrations in undisturbed soils. The Background soil Characterization Project (BSCP) was undertaken to provide background concentration data on potential contaminants in natural soils on the Oak Ridge Reservation (ORR). The objectives of the BSCP are to provide baseline data for contaminated site assessment and estimates of potential human health risk associated with background concentrations of hazardous and other constituents in native soils. This report presents, evaluates, and documents data and results obtained in Phase I of the project. It is intended to be a stand-alone document for application and use in structuring and conducting remedial investigation and remedial action projects in the Environmental Restoration (ER) Program.

  6. Accumulation of 137Cs and 90Sr in wood and bark of various types of oak and black alder plantings

    International Nuclear Information System (INIS)

    Perevolotskij, A.N.; Bulavik, I.M.; Perevolotskaya, T.V.; Paskrobko, L.A.; Andrush, S.N.

    2008-01-01

    Results of the evaluation of the influence of types of habitat edaphic conditions on 137Cs and 90Sr transition coefficients and their accumulation by wood and bark of English oak (Quercus robur L.) and black alder (Alnus glutinosa (L.) Gaertn) were presented. There was observed the particular influence of edaphic conditions on 137Cs and 90Sr accumulation by wood and bark of English oak. Lowering of 137Cs transition coefficients for the studied elements of phytomass was noted in the conditions of soil fertility increasing. Influence of soil moistening on 137Cs transition into wood and bark of oak trees was stated only in wood-sorrel and glague types of forests. Differences in accumulation of 90Sr by wood and bark of English oak in the studied range of edaphotopes were not proved. There was not found any differences in accumulation of both radionuclides by black alder trees in the typical for them edaphic conditions

  7. Factors affecting spatial variation of annual apparent Q₁₀ of soil respiration in two warm temperate forests.

    Directory of Open Access Journals (Sweden)

    Junwei Luan

    Full Text Available A range of factors has been identified that affect the temperature sensitivity (Q₁₀ values of the soil-to-atmosphere CO₂ flux. However, the factors influencing the spatial distribution of Q₁₀ values within warm temperate forests are poorly understood. In this study, we examined the spatial variation of Q₁₀ values and its controlling factors in both a naturally regenerated oak forest (OF and a pine plantation (PP. Q₁₀ values were determined based on monthly soil respiration (R(S measurements at 35 subplots for each stand from Oct. 2008 to Oct. 2009. Large spatial variation of Q₁₀ values was found in both OF and PP, with their respective ranges from 1.7 to 5.12 and from 2.3 to 6.21. In PP, fine root biomass (FR (R = 0.50, P = 0.002, non-capillary porosity (NCP (R = 0.37, P = 0.03, and the coefficients of variation of soil temperature at 5 cm depth (CV of T₅ (R = -0.43, P = 0.01 well explained the spatial variance of Q₁₀. In OF, carbon pool lability reflected by light fractionation method (LLFOC well explained the spatial variance of Q₁₀ (R = -0.35, P = 0.04. Regardless of forest type, LLFOC and FR correlation with the Q₁₀ values were significant and marginally significant, respectively; suggesting a positive relationship between substrate availability and apparent Q₁₀ values. Parameters related to gas diffusion, such as average soil water content (SWC and NCP, negatively or positively explained the spatial variance of Q₁₀ values. Additionally, we observed significantly higher apparent Q₁₀ values in PP compared to OF, which might be partly attributed to the difference in soil moisture condition and diffusion ability, rather than different substrate availabilities between forests. Our results suggested that both soil chemical and physical characters contributed to the observed large Q₁₀ value variation.

  8. Consumption and reaccumulation of forest fuels in oak shelterwood stands managed with prescribed fire

    Science.gov (United States)

    Patrick H. Brose

    2016-01-01

    In the shelterwood-burn technique, a moderate- to high-intensity growing-season prescribed fire is essential to achieve desired oak regeneration goals. These levels of fire intensity are dependent on the increased fuel loadings created by the preceding first removal cut. However, the loadings of forest fuels and their fluctuation during implementation of the...

  9. 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

  10. 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.

  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. An evaluation of seven methods for controlling mountain laurel thickets in the mixed-oak forests of the central Appalachian Mountains, USA

    Science.gov (United States)

    Patrick H. Brose

    2017-01-01

    In the Appalachian Mountains of eastern North America, mountain laurel (Kalmia latifolia) thickets in mixed-oak (Quercus spp.) stands can lead to hazardous fuel situations, forest regeneration problems, and possible forest health concerns. Therefore, land managers need techniques to control mountain laurel thickets and limit...

  13. 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?

  14. 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.

  15. A compartment model of plutonium dynamics in a deciduous forest ecosystem

    International Nuclear Information System (INIS)

    Garten, C.T. Jr.; Gardner, R.H.; Dahlman, R.C.

    1978-01-01

    A linear compartment donor-controlled model was designed to describe and simulate the behaviour of plutonium ( 239 , 240 Pu) in a contaminated deciduous forest ecosystem at Oak Ridge, Tennessee. At steady states predicted by the model, less than 0.25% of the Pu in the ecosystem resides in forest biota. Soil is the major repository of Pu in the forest, and reciprocal exchanges of Pu between soil and litter or soil and tree roots were dominant transfers affecting the ecosystem distribution of Pu. Variation in predicted steady state amounts of Pu in the forest, given variability in the model parameters, indicated that ones ability to develop reliable models of Pu transport in ecosystems will improve with greater precision in data from natural environments and a better understanding of sources of variation in Pu data. (author)

  16. Radionuclides in a deciduous forest surrounding a shallow-land-burial site in the eastern United States

    International Nuclear Information System (INIS)

    Rickard, W.H.; Kirby, L.J.; McShane, M.C.

    1981-06-01

    The objective of this study was to determine if radioactive materials buried in trenches at the Maxey Flats burial ground in eastern Kentucky have migrated into the surrounding oak-hickory forest. Forest floor litter, minearl soil, and tree leaves were sampled and the radionuclide content measured

  17. 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.

  18. 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.

  19. 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

  20. Modeling the effects of harvest alternatives on mitigating oak decline in a Central Hardwood Forest landscape

    Science.gov (United States)

    Wen J. Wang; Hong S. He; Martin A. Spetich; Stephen R. Shifley; Frank R. III Thompson; Jacob S. Fraser

    2013-01-01

    Oak decline is a process induced by complex interactions of predisposing factors, inciting factors, and contributing factors operating at tree, stand, and landscape scales. It has greatly altered species composition and stand structure in affected areas. Thinning, clearcutting, and group selection are widely adopted harvest alternatives for reducing forest...

  1. 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)

  2. Soil sampling and analysis plan for the Bear Creek Valley floodplain at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-11-01

    This Sampling and Analysis Plan (SAP) for the Bear Creek Valley (BCV) Floodplain presents the approach and rationale for characterizing potentially contaminated soils and sediments of the Bear Creek floodplain and the impact of any contaminants on the floodplain ecosystem. It is an addendum to a previously issued document, the Remedial Investigation Work Plan for Bear Creek (Y02-S600) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee (ES/ER-19&D2), which presents background information pertaining to this floodplain investigation. The strategy presented in the SAP is to divide the investigation into three component parts: a large-scale characterization of the floodplain; a fine-scale characterization of the floodplain beginning with a known contaminated location; and a stream sediment characterization. During the large-scale and the fine-scale characterizations, soil and biota samples (i.e., small mammals, earthworms, and vegetation) will be collected in order to characterize the nature and extent of floodplain soil contamination and the impact of this contamination on floodplain biota. The fine-scale characterization will begin with an investigation of a site corresponding to the location noted in the Remedial Investigation Work Plan (ES/ER-19&D2) as an area where uranium and PCBs are concentrated in discrete strata. During this fine-scale characterization, a 1 m deep soil profile excavation will be dug into the creek berm, and individual soil strata in the excavation will be screened for alpha radiation, PCBs, and VOCs. After the laboratory analysis results are received, biota samples will be collected in the vicinity of those locations.

  3. 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).

  4. 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.

  5. Model of plutonium dynamics in a deciduous forest ecosystem

    International Nuclear Information System (INIS)

    Garten, C.T. Jr.; Gardner, R.H.; Dahlman, R.C.

    1980-01-01

    A linear compartment model with donor-controlled flows between compartments was designed to describe and simulate the behavior of plutonium ( 239 240 Pu) in a contaminated forest ecosystem at Oak Ridge, TN. At steady states predicted by the model, less than 0.25% of the plutonium in the ecosystem resides in biota. Soil is the major repository of plutonium in the forest, and exchanges of plutonium between soil and litter or soil and tree roots were dominant transfers affecting the ecosystem distribution of plutonium. Variation in predicted steady-state amounts of plutonium in the forest, given variability in the model parameters, indicates that our ability to develop models of plutonium transport in ecosystems should improve with greater precision in data from natural environments and a better understanding of sources of variation in plutonium data

  6. 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.

  7. More an Exception Than the Rule: Fire has Little Effect on the Magnetic Properties of Loessic Soils Along the Prairie - Forest Ecotone in the Midwestern United States

    Science.gov (United States)

    Geiss, C. E.

    2016-12-01

    The analysis of a soil profile in western Iowa suggests that forest fires along the prairie-forest ecotone have little effect on the overall magnetic properties of the soil. The studied soil profile is located at Hitchcock Nature Center near Honey Creek, Iowa (41°25'15"N, -95°51'56"W) and developed in a narrow ravine in the Iowa Loess Hills. The surrounding vegetation consists of hardwoods, while the surrounding ridges are vegetated by oak savanna. The area has been subjected to prescribed fires for almost 20 years and is estimated to have burned approximately every 5 years in pre-European times [Stambaugh et al., 2006]. The profile contains several buried soils interspersed by often rapidly deposited loess. Paleosols consist of strongly developed A-horizons but show only weak magnetic enhancement in terms of magnetic susceptibility or ARM/IRM ratios. In a plot of χARM/χFD vs. χARM/χ, all but one sample plot far from the region that is generally associated with past burning [Oldfield and Crowther, 2007]. As shown earlier for prairie environments, fires in oak savanna do not seem to burn hot enough to cause widespread magnetic mineral transformations. Oldfield, F., and J. Crowther (2007), Establishing fire incidence in temperate soils using magnetic measurements, Paleogeogr. Paleoclim. Paleoecol., 249, 362-369. Stambaugh, M. C., R. P. Guyette, E. R. McMurry, and D. C. Dey (2006), Fire history at the eastern Great Plains margin, Missouri River Loess Hills, Great Plains Research, 16, 149-159.

  8. Hyperdiversity of ectomycorrhizal fungus assemblages on oak seedlings in mixed forests in the southern Appalachian Mountains

    Science.gov (United States)

    John F. Walker; Orson K. Miller; Jonathan L. Horton

    2005-01-01

    Diversity of ectotrophic mycobionts on outplanted seedlings of two oak species (Quercus rubra and Quercus prinus) was estimated at two sites in mature mixed forests in the southern Appalachian Mountains by sequencing nuclear 5.8S rRNA genes and the flanking internal transcribed spacer regions I and II (ITS). The...

  9. Indiana's Forests 2008

    Science.gov (United States)

    Christopher W. Woodall; Mark N. Webb; Barry T. Wilson; Jeff Settle; Ron J. Piva; Charles H. Perry; Dacia M. Meneguzzo; Susan J. Crocker; Brett J. Butler; Mark Hansen; Mark Hatfield; Gary Brand; Charles. Barnett

    2011-01-01

    The second full annual inventory of Indiana's forests reports more than 4.75 million acres of forest land with an average volume of more than 2,000 cubic feet per acre. Forest land is dominated by the white oak/red oak/hickory forest type, which occupies nearly a third of the total forest land area. Seventy-six percent of forest land consists of sawtimber, 16...

  10. Distribution and eco-coenotic patterns of the forest orchid Epipactis pontica in Slovakia

    Directory of Open Access Journals (Sweden)

    Richard Hrivnák

    2014-07-01

    Full Text Available The present study is aimed at characterising the ecological niche of a typical forest orchid (Epipactis pontica in Slovakia. Vegetation-environmental data were collected across mountain ranges and  their foothills in the Western Carpathians in 2011. Numerical classification was performed to delimit the main forest vegetation types and a linear mixed effect model was applied to reveal differences between plots with versus without E. pontica. This endangered species of Slovak flora grows in thermophilous turkey oak forests (Quercion confertae-cerris, mesophilous broad-leaved mixed oak-hornbeam forests (Carpinion betuli, but most stands correspond to the acidic (Luzulo-Fagion sylvaticae and mesotrophic beech forests (Fagion sylvaticae. Principal component analysis supported the floristic separation of plant communities and showed some significant vegetation environmental relationships. E. pontica prefers forests with closed canopy (mean canopy openness: 8.5–15.1% occurring especially on slightly acidic (soil reaction: 4.48–5.65 and nutrient-poor soils (soil conductivity: 43.1–72.6 μS/cm. The proposed Ellenberg indicator values for light (4, temperature (5, continentality (4, moisture (5, soil reaction (6 and nutrients (5 follow species composition pattern of vascular plants in Slovak phytosociological relevés with E. pontica occurrence. They are also in accordance with its habitat conditions and ecological requirements in other parts of its range. The linear mixed effect model did not confirm any environmental peculiarity of plots with the presence of E. pontica at a microscale level and this result was consistent across the studied sites.

  11. Microsatellite Primer Development for Post Oak, Quercus stellata (Fagaceae

    Directory of Open Access Journals (Sweden)

    Warren B. Chatwin

    2014-10-01

    Full Text Available Premise of the study: The American Cross Timbers forest ecosystem runs from southeastern Kansas to Central Texas and is primarily composed of post oak (Quercus stellata. This old-growth forest currently occupies only about 2% of its ancestral range. To facilitate genetic research on this species, we developed microsatellite primers specific to post oak from reduced genomic libraries. Methods and Results: Two Q. stellata individuals, sampled from the northern and southern range of the post oak forest, were subject to genomic reduction and 454 pyrosequencing. Bioinformatic analysis identified putative microsatellites from which 12 polymorphic primer sets were screened on three populations. The number of alleles observed ranged from five to 20 across all populations, while observed and expected heterozygosity values ranged from 0.05 to 0.833 and 0.236 to 0.893, respectively, within individual populations. Conclusions: We report the development of microsatellite markers, specific to post oak, to aid the study of genetic diversity and population structure of extant forest remnants.

  12. Spatial Upscaling of Soil Respiration under a Complex Canopy Structure in an Old‐Growth Deciduous Forest, Central Japan

    Directory of Open Access Journals (Sweden)

    Vilanee Suchewaboripont

    2017-01-01

    Full Text Available The structural complexity, especially canopy and gap structure, of old‐growth forests affects the spatial variation of soil respiration (Rs. Without considering this variation, the upscaling of Rs from field measurements to the forest site will be biased. The present study examined responses of Rs to soil temperature (Ts and water content (W in canopy and gap areas, developed the best fit modelof Rs and used the unique spatial patterns of Rs and crown closure to upscale chamber measurements to the site scale in an old‐growth beech‐oak forest. Rs increased with an increase in Ts in both gap and canopy areas, but the effect of W on Rs was different between the two areas. The generalized linear model (GLM analysis identified that an empirical model of Rs with thecoupling of Ts and W was better than an exponential model of Rs with only Ts. Moreover, because of different responses of Rs to W between canopy and gap areas, it was necessary to estimate Rs in these areas separately. Consequently, combining the spatial patterns of Rs and the crown closure could allow upscaling of Rs from chamber‐based measurements to the whole site in the present study.

  13. The Turkey oak high forests in the Molise region (central Italy. Analysis of past silvicultural system and current management choices.

    Directory of Open Access Journals (Sweden)

    Paolo Cantiani

    2010-12-01

    Full Text Available Normal 0 14 false false false MicrosoftInternetExplorer4 Aim of the work is to provide further knowledge on the silvicultural system applied to Quercus cerris hight forests in the Molise Region (Central Italy. An historical analysis, based on a number of forest management plans applied since 1940 referred to 19 municipalities and on other historical documents, is provided in the paper. Forest management has been traditionally applied in the Molise Region and therefore is at now possible to reconstruct in detail the management of the forests of Molise Region. The historical study has been integrated with the analysis of a chronosequence including four steps of stand development in a Turkey oak stand: the regeneration phase (1-2 yrs - the unthinned young stand (46 yrs - the unthinned adult stand (aged 60 to 100 - the mature stand (126 yrs. Mensurational surveys were carried out at each phase in order to characterize both stand structure and derive information on the silvicultural practices applied in the past, but not documented in the available papers. The stand age was determined by tree coring and count of annual rings. At the beginning of the last century, the silvicultural system to be applied in oak high forests wasn’t strictly defined and a particular kind of selection cutting was carried out. It was named taglio a salto per sezioni i.e. “compartment selection cutting”, partly leading back to a real selection cutting, partly to a shelterwood system. The use of the reported silvicultural system gave rise to irregular forest structures and led to management problems well-described in the management plans at the end of 1940s. Another consequence of the applied practices was the absence or the inadequate natural regeneration establishment. The contemporary unregulated practice of grazing the forest floor contributed to the unsuccessful regeneration and made the situation worse. The presence of an understorey layer made up by sproutings

  14. 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...

  15. 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.

  16. BANCO DE SEMILLAS EN UN BOSQUE DE ROBLE DE LA CORDILLERA CENTRAL COLOMBIANA SOIL SEED BANK IN AN OAK FOREST FROM THE COLOMBIAN CENTRAL CORDILLERA

    Directory of Open Access Journals (Sweden)

    Luz Bibiana Moscoso Marín

    2005-12-01

    they stores species ready to germinate when a perturbation occurs or when environmental conditions change to start the successional process. The main objective of this research was to evaluate the spatial variation of seed banks and its relation with the current vegetation in a highland Andean forest dominated by oak (Quercus humbodtii Bonpl. at 2.290 m.a.s.l. in the watershed of the Piedras Blancas stream, in the department of Antioquia, Colombia. We sampled 57 points in a 6.400 m² plot established in that forest. In each point we collected one sample each of litter and soil. We also established five subplots of 160 m²each for sampling vegetation. Seed banks were assessed by the method of direct germination. We obtained 204 trees belonging to 25 families and 41 genera. The most representative tree species were Alfaroa cf. colombiana, Myrcia popayanensis Rich. and Quercus humboldtii Bonpl. We obtained 428 individuals from soil samples and 113 individuals from litter samples in the germination trial, belonging to 20 morpho species. Species composition of the soil seed bank did not reflect the composition of the forest vegetation, and we found mainly herbaceous and shrub vegetation. Litter had 198 seeds m-2 and soil had 4.330 seeds m-2. There was large spatial variation in the amount of seeds in this forest fragment.

  17. 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

  18. Climate and Landuse Change Impacts on hydrological processes and soil erosion in a dry Mediterranean agro-forested catchment, southern Portugal

    Science.gov (United States)

    Santos, Juliana; Nunes, João Pedro; Sampaio, Elsa; Moreira, Madalena; Lima, Júlio; Jacinto, Rita; Corte-Real, João

    2014-05-01

    Climate change is expected to increase aridity in the Mediterranean rim of Europe, due to decreasing rainfall and increasing temperatures. This could lead to impacts on soil erosion, since the lower rainfall could nevertheless become concentrated in higher intensity events during the wet season, while the more arid conditions could reduce vegetation cover, also due to climate-induced land-use changes. In consequence, there is an interest in understanding how climate change will affect the interaction between the timing of extreme rainfall events, hydrological processes, vegetation growth, soil cover and soil erosion. To study this issue, the SWAT eco-hydrological model was applied to Guadalupe, an agro-forested catchment (446 ha) located close to the city of Évora, with a Mediterranean inland climate. The landcover is a mix of dispersed cork oak forests ("montado"), annual crops, and agroforesty regions where the cork oaks are associated with crops or pasture; this land cover is representative of the dry regions of southern Portugal and Spain. The catchment has been instrumented since 2011 with a hydrometric station (water discharge and suspended sediment concentration data) and a soil moisture measurement station. There is also observed data of actual evapotranspiration, LAI and biomass production (in pasture; from 1999 and 2008) and runoff data and sediment yield measured in six 16m2 plots. Water balance, vegetation growth, soil erosion and sediment yield in SWAT was calibrated with this dataset. This work will present the dataset, modeling process, results for impacts of climate and land-use change scenarios for vegetation growth, soil erosion and sediment export, considering the climate and socio-economic scenarios A1b and B1 (based on SRES storylines). Climate scenarios were created by statistical downscaling from Global Circulation Models (GCMs) for the period 2071-2100 (30 years). The reference period was 1971-2000 (30 years). The SWAT model was used to

  19. 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

  20. New relationships among the sudden oak death pathogen, bark and ambrosia beetles, and fungi colonizing coast live oaks

    Science.gov (United States)

    Nadir Erbilgin; Brice A. McPherson; Pierluigi Bonello; David L. Wood; Andrew J. Nelson

    2008-01-01

    Sudden oak death (SOD) has had devastating effects on several oak species in many California coastal forests. Phytophthora ramorum has been identified as the primary causal agent of sudden oak death. While the pathogen may be capable of killing mature trees, it is likely that in nature opportunistic organisms play significant roles in the decline and...

  1. A meta-analysis of the fire-oak hypothesis: Does prescribed burning promote oak reproduction in eastern North America

    Science.gov (United States)

    Patrick H. Brose; Daniel C. Dey; Ross J. Phillips; Thomas A. Waldrop

    2013-01-01

    The fire-oak hypothesis asserts that the current lack of fire is a reason behind the widespread oak (Quercus spp.) regeneration difficulties of eastern North America, and use of prescribed burning can help solve this problem. We performed a meta-analysis on the data from 32 prescribed fire studies conducted in mixed-oak forests to test whether they...

  2. Soil sampling and analysis plan for the Bear Creek Valley floodplain at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1994-11-01

    This Sampling and Analysis Plan (SAP) for the Bear Creek Valley (BCV) Floodplain presents the approach and rationale for characterizing potentially contaminated soils and sediments of the Bear Creek floodplain and the impact of any contaminants on the floodplain ecosystem. It is an addendum to a previously issued document, the Remedial Investigation Work Plan for Bear Creek (Y02-S600) at the Oak Ridge Y-12 Plant, Oak Ridge, Tennessee (ES/ER-19 ampersand D2), which presents background information pertaining to this floodplain investigation. The strategy presented in the SAP is to divide the investigation into three component parts: a large-scale characterization of the floodplain; a fine-scale characterization of the floodplain beginning with a known contaminated location; and a stream sediment characterization. During the large-scale and the fine-scale characterizations, soil and biota samples (i.e., small mammals, earthworms, and vegetation) will be collected in order to characterize the nature and extent of floodplain soil contamination and the impact of this contamination on floodplain biota. The fine-scale characterization will begin with an investigation of a site corresponding to the location noted in the Remedial Investigation Work Plan (ES/ER-19 ampersand D2) as an area where uranium and PCBs are concentrated in discrete strata. During this fine-scale characterization, a 1 m deep soil profile excavation will be dug into the creek berm, and individual soil strata in the excavation will be screened for alpha radiation, PCBs, and VOCs. After the laboratory analysis results are received, biota samples will be collected in the vicinity of those locations

  3. Modeling the health and productivity of Oak Savannas in central USA

    Science.gov (United States)

    Nightingale, J. M.; Hill, M. J.

    2012-12-01

    Oak species have a long history of domination in eastern North America and their present distribution in various regions exceeds that recorded in the original forests at the time of European settlement. The increase in oak during the late 18th and 19th centuries can be attributed to historical changes in disturbance regimes in the eastern biome. The expansion in oak distribution has occurred on xeric or nutrient-poor sites, which indicates the stress tolerance capabilities of many oak species. The aim of this research is to assess the health and productivity of the fragmented oak savannas that span from Texas north to the Canada border using statewide GAP, climate and MODIS data and the 3PGS (Physiological Principles Predicting Growth using satellite data) ecosystem process model. 3-PGS is a simple big-leaf productivity model that sets upper limits on monthly gross primary productivity (GPP) by determining the amount of photosynthetically active radiation absorbed (APAR) by vegetation and the photosynthetic capacity (LUE) of the canopy. The utilized portion of APAR is calculated by reducing total PAR by an amount determined by the most constraining of a series of environmental modifiers that affect gas exchange through stomata. These include: (a) high daytime atmospheric VPD; (b) soil water availability; and (c) the frequency of sub-freezing temperatures (<-2 °C). Climate data including day length, precipitation, average temperature and vapor pressure deficit are obtained from the Daymet daily gridded surface data from Oak Ridge National Laboratory (ORNL). The fraction of APAR is obtained from the MODIS terra/aqua combined product. Monthly surfaces were derived for the study period 2003-2008 spanning available MODIS and Climate datasets. Soil properties for the entire U.S.A., derived from luster analysis of STATSGO soil parameters, terrain and climate observations were obtained from ORNL. Oak savannas within this region are identified using the statewide Gap

  4. 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...

  5. 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...

  6. Final report on the Background Soil Characterization Project at the Oak Ridge Reservation, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    Hatmaker, T.L.; Hook, L.A.; Jackson, B.L.

    1993-10-01

    The Background Soil Characterization Project (BSCP) will provide background concentration levels of selected metals, organic compounds, and radionuclides in soils from uncontaminated on-site areas at the Oak Ridge Reservation (ORR), and off-site in the western part of Roane County and the eastern part of Anderson County. The BSCP will establish a database, recommend how to use the data for contaminated site assessment, and provide estimates of the potential human health and environmental risks associated with the background level concentrations of potentially hazardous constituents. ORR background soil characterization data will be used for two purposes. The first application will be in differentiating between naturally occurring constituents and site-related contamination. This is a very important step in a risk assessment because if sufficient background data are not available, no constituent known to be a contaminant can be eliminated from the assessment even if the sampled concentration is measured at a minimum level. The second use of the background data will be in calculating baseline risks against which site-specific contamination risks can be compared

  7. 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...

  8. 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

  9. 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

  10. Exploring soil water budget of a pristine oak wood in peri-urban Rome, central Italy

    Directory of Open Access Journals (Sweden)

    Valerio Moretti

    2014-06-01

    Full Text Available 72 544x376 Normal 0 14 false false false IT X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Tabella normale"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0cm 5.4pt 0cm 5.4pt; mso-para-margin:0cm; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif";} Exploring soil water budget of a pristine oak wood in peri-urban Rome, central Italy. The water budget in bounded and fenced areas was assessed by analyzing pedo-climatic conditions and the soil moisture content. Water content in the soil was measured using a Theta Probe Soil Moisture sensor (ML2x by Delta-T-Devices with a direct read-out device that provides soil moisture estimates as percent volume. The correlation between the experimental values obtained by the gravimetricmethod and thevalues directly measured by Theta Probe was found significant. Soil moisture at 100 cm depth indicates soil water as permanently available for plants through the year except during exceptionally dry summer periods. Therefore, oaks experienced no water deficiency with normal rainfall rates, possibly suffering root asphyxia during rainy years. Results are collected in fenced areas, sheltered by the action of the local fauna.

  11. 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...

  12. 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)

  13. 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.

  14. Phytosociological characteristics of forest vegetation NPR Dubnik

    International Nuclear Information System (INIS)

    Hrabovsky, A.; Balkovic, J.; Kollar, J.

    2010-01-01

    National Wildlife (NPR) Dubnik represents a unique fragment of natural forest vegetation in the region of Nitra loess upland. Status of oak and oak-hornbeam forests in this book was last documented in 1965. The aim of the contribution is to assess the current status of forest vegetation in the NPR Dubnik by modern methods of phytosociology in accordance with current thinking on the classification of oak and oak-hornbeam forests.

  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. Assessing the risk caused by ground level ozone to European forest trees: A case study in pine, beech and oak across different climate regions

    International Nuclear Information System (INIS)

    Emberson, Lisa D.; Bueker, Patrick; Ashmore, Mike R.

    2007-01-01

    Two different indices have been proposed for estimation of the risk caused to forest trees across Europe by ground-level ozone, (i) the concentration based AOT40 index (Accumulated Over a Threshold of 40 ppb) and (ii) the recently developed flux based AFstY index (Accumulated stomatal Flux above a flux threshold Y). This paper compares the AOT40 and AFstY indices for three forest trees species at different locations in Europe. The AFstY index is estimated using the DO 3 SE (Deposition of Ozone and Stomatal Exchange) model parameterized for Scots pine (Pinus sylvestris), beech (Fagus sylvatica) and holm oak (Quercus ilex). The results show a large difference in the perceived O 3 risk when using AOT40 and AFstY indices both between species and regions. The AOT40 index shows a strong north-south gradient across Europe, whereas there is little difference between regions in the modelled values of AFstY. There are significant differences in modelled AFstY between species, which are predominantly determined by differences in the timing and length of the growing season, the periods during which soil moisture deficit limits stomatal conductance, and adaptation to soil moisture stress. This emphasizes the importance of defining species-specific flux response variables to obtain a more accurate quantification of O 3 risk. - A new flux-based model provides a revised assessment of risks of ozone impacts to European forests

  17. A δ(15)N assessment of nitrogen deposition for the endangered epiphytic orchid Laelia speciosa from a city and an oak forest in Mexico.

    Science.gov (United States)

    Díaz-Álvarez, Edison A; Reyes-García, Casandra; de la Barrera, Erick

    2016-09-01

    Atmospheric nitrogen deposition poses a major threat to global biodiversity. Tropical epiphytic plants are especially at risk given their reliance on atmospheric sources of nutrients. The leaf, pseudobulb, and root carbon and nitrogen content, C:N ratio, as well as the nitrogen isotopic composition were studied for individuals of Laelia speciosa from a city and from an oak forest in Mexico. The nitrogen content of leaves was similar between the city and the oak forest, reaching 1.3 ± 0.2 % (dry mass). The δ(15)N of leaves, pseudobulbs, and roots reached 5.6 ± 0.2 ‰ in the city, values found in sites exposed to industrial and vehicular activities. The δ(15)N for plant from the oak forest amounted to -3.1 ± 0.3 ‰, which is similar to values measured from sites with low industrial activities. Some orchids such as Laelia speciosa produce a single pseudobulb per year, i.e., a water and nutrient storage organ, so the interannual nitrogen deposition was studied by considering the ten most recent pseudobulbs for plants from either site formed between 2003 and 2012. The C:N ratio of the ten most recent pseudobulbs from the oak forest, as well as that of the pseudobulbs formed before 2010 for plants in the city were indistinguishable from each other, averaging 132.4 ± 6.5, while it was lower for the two most recent pseudobulbs in the city. The δ(15)N values of pseudobulbs from the oak forest averaged ‒4.4 ± 0.1 ‰ for the entire series. The δ(15)N ranged from 0.1 ± 1.6 ‰ for the oldest pseudobulb to 4.7 ± 0.2 ‰ for the pseudobulb formed in the city from 2008 onwards. Isotopic analysis and the C:N ratio for L. speciosa revealed that rates of nitrogen deposition were higher in the city than in the forest. The δ(15)N values of series of pseudobulbs showed that it is possible to track nitrogen deposition over multiple years.

  18. 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

  19. Sludge application and monitoring program on the Oak Ridge Reservation, 1986 through 1993

    Energy Technology Data Exchange (ETDEWEB)

    Gunderson, C.A.; Boston, H.L.; Van Miegroet, H., Morris, J.L.; Larsen, I.L.; Walzer, A.E.; Adler, T.C.; Bradburn, D.M.; Huq, M.

    1995-08-01

    Municipal sewage sludge has been applied to forests and pastures on the DOE (U.S. Department of Energy) Oak Ridge Reservation (ORR) since 1983 as a method of both disposal and beneficial reuse. Application was carried out under State of Tennessee permits issued to the City of Oak Ridge for land disposal of. sewage sludge. In conjunction with these applications, information has been collected concerning sludge quantity and characteristics, soil parameters, soil water constituents, groundwater quality, surface runoff water quality, and various chemical constituents in vegetation on application sites. This information provides (1) a record of sludge application on the DOE ORR, and (2) documentation of changes in soil parameters following sludge application. The information also provides a basis for evaluating the implications of the land application of municipal sewage sludge for soil and water quality and for evaluating the fate of sludge constituents when sludge is either sprayed onto or injected into pasture sites or applied to the surface of forested sites. This report covers in detail sludge applications conducted from 1986 through 1993, with some data from the period between 1983 and 1986. Land application has been recommended by the U.S. Environmental Protection Agency as a desirable alternative for disposal of ORR waste. Municipal sewage sludge is in many ways similar to dilute animal manure fertilizer, but it also contains metals, organic chemicals, human pathogens, and other constituents reflective of inputs into the municipal sewage treatment plant. When applied to land, nutrients in the sludge improve soil fertility, and minerals and organic matter in the sludge improve soil structure. Under optimal conditions, metals are immobilized, and organic chemicals and pathogens are immobilized or destroyed. If the sludge is not managed effectively, however, sludge constituents have the potential to affect human health and the environment.

  20. 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

  1. 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

  2. The Effects of Detritus Input on Soil Organic Matter Content and Carbon Dioxide Emission in a Central European Deciduous Forest

    Directory of Open Access Journals (Sweden)

    FEKETE, István

    2011-01-01

    Full Text Available A major objective of our research was to survey soil biological activity and organic mattercontent reduction in a Central European oak forest during treatments of various detritus inputs within theSíkfkút DIRT (Detritus Input and Removal Treatments Project. Beside the control, three detritusremoval and two detritus duplication treatments were applied. Our examinations have proven that soilorganic matter content declined relatively fast in detritus removal treatments. The reduction wasespecially remarkable in root detritus removal treatments, where – due to the lack of transpiration – soilswere moister during the whole year than in the other treatments. The higher moisture content, despite ofthe reduction of detritus input, produced an intense soil respiration. This can be explained by the fact thatdecomposing organisms have increased the use of soil organic matter. Detritus input reduction had asignificantly greater effect on soil respiration and organic matter content than detritus input duplicationof the same extent. The latter did not cause any significant change compared to the control.

  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. An approximation to the fauna associated with oak forests of Guantiva- La Rusia - Iguaque corridor (Boyaca-Santander, Colombia)

    International Nuclear Information System (INIS)

    Saenz Jimenez, Fausto Alexis

    2010-01-01

    There were 380 species of vertebrates in the Guantiva - La Rusia - Iguaque corridor, distributed in 256 birds, 83 mammals, 31 amphibians and 10 reptiles. Twenty correspond to endangered species (10 amphibians, 8 birds and 2 mammals), 28 to endemic species (21 amphibians, 5 birds and 3 mammals) and 15 to migratory bird species. One hundred and three species were associated with oak forests of the corridor; comprising 62 birds, 18 mammals, 22 amphibians and 1 reptile species. Birds of the families Cracidae, Grallaridae, Phasianidae, Picidae, Psittacidae Trogonidae, mammals of the families Phyllostomidae, Sciuridae, Centrolenidae and amphibians of the family Strabomantidae had the highest number of species associated with oak. The amphibians were most frequently associated with these ecosystems, since 58% of the species of this group have a preference for habitats with oak presence.

  5. Spatio-temporal analysis of oak forests (Quercus humboldtii Bonpl.) change and its relationship with pottery at Aguabuena (Raquira-Boyaca)

    International Nuclear Information System (INIS)

    Moncada Rasmussen, Dora Maria

    2010-01-01

    This research was conducted at Aguabuena, Raquira-Boyaca, and the main objective was to identify the changes in the settlement patterns and oak - forest cover, due to the development of new technologies and destinies for ceramics production. The study was carried out using aerial photographs from 1985 and 1993 processed in ArcGIS v. 9.0, as well as the application of participatory methods and spatial statistics. The spatio-temporal analysis of the forests allowed the measurement of perimeter and area changes and the number of fragments, where the loss of forest cover was 43.43% for the evaluated years. For analytical purposes related to the ceramics production organization, two different types of workshops can be pointed out: Domestic and Family - Industry. In the Domestic workshops spatial aggregation is due to the forest presence, its relative and different antiquity. The family - indus try- workshops are located along roads, for their relatives and population increment. Each ceramic production system represents different forms of relations with nature; the domestic ones are located in the oaks forests, using high quality fuel in the heating ceramics, while the Industrial-Family looks for the roads with the purpose of centralizing the production and favoring the intermediate relations. These two modes of production reflect the human role in the change and creation of new land scapes from the pottery.

  6. Effects of soil pollutants, biogeochemistry and microbiology on the distribution and composition of enchytraeid communities in urban and suburban holm oak stands

    International Nuclear Information System (INIS)

    Rota, Emilia; Caruso, Tancredi; Monaci, Fabrizio; Baldantoni, Daniela; De Nicola, Flavia; Iovieno, Paola; Bargagli, Roberto

    2013-01-01

    Holm oaks form typical urban woodlands in the Mediterranean region. We aimed at characterizing the enchytraeid communities in these environments and searching for possible correlations with soil parameters, including the traffic contamination. Samples of litter and topsoil were collected at different spatial scales and seasons in Naples and Siena cities and in two suburban stands. Only the co-variation between pollution and other soil chemico-physical factors showed significant effects, whereas no direct effect of soil microbiology was detected. Some thermophilous Fridericia and Achaeta tolerate high concentrations of heavy metals and PAHs and their abundance was mainly determined by Ca bioavailability. Central-European mesophilous species increased significantly under more temperate environmental conditions. Different combinations of soil cohesiveness, grain size composition and moisture regime seem to select species of certain body sizes. -- Highlights: •We examined the enchytraeid assemblages of urban holm oak stands in relation to pollution gradients. •Only the co-variation between pollution and other soil chemico-physical factors showed significant effects. •Thermophilous species in Fridericia and Achaeta are mainly affected by Ca bioavailability. -- The co-variation between pollution and other soil chemico-physical factors affects significantly the enchytraeid communities in Mediterranean urban holm oak stands

  7. 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.

  8. 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...

  9. Forest structure of oak plantations after silvicultural treatment to enhance habitat for wildlife

    Science.gov (United States)

    Twedt, Daniel J.; Phillip, Cherrie-Lee P.; Guilfoyle, Michael P.; Wilson, R. Randy; Schweitzer, Callie Jo; Clatterbuck, Wayne K.; Oswalt, Christopher M.

    2016-01-01

    During the past 30 years, thousands of hectares of oak-dominated bottomland hardwood plantations have been planted on agricultural fields in the Mississippi Alluvial Valley. Many of these plantations now have closed canopies and sparse understories. Silvicultural treatments could create a more heterogeneous forest structure, with canopy gaps and increased understory vegetation for wildlife. Lack of volume sufficient for commercial harvest in hardwood plantations has impeded treatments, but demand for woody biomass for energy production may provide a viable means to introduce disturbance beneficial for wildlife. We assessed forest structure in response to prescribed pre-commercial perturbations in hardwood plantations resulting from silvicultural treatments: 1) row thinning by felling every fourth planted row; 2) multiple patch cuts with canopy gaps of gaps appear likely to be filled by regenerating saplings.

  10. Cycling of radiocesium in forest ecosystems

    International Nuclear Information System (INIS)

    Myttenaere, C.; Sombre, L.; Thiry, Y.; Brouwer, S. de; Ronneau, C.

    1993-01-01

    A review is given of results on 137 Cs and potassium behavior in forest ecosystems following an atmospheric contamination after an accidental release. Data are given on the correlation coefficients 137 Cs versus K in the Belgian Ardennes forest in the period December 1988 to March 1990. Experiments were performed in Norwegian spruce and oak stands. Data are also given on 137 Cs distribution in soil layers of Bourakovka and Novo-Shepelichi polygons in the Chernobyl-contaminated area, and on radiocesium contamination of the red pine stand in Bourakovka. A correlation was found in the behavior of both elements in plants. Observations and studies of their behavior in multilayer soils, however, showed some discrepancies. (J.B.) 4 tabs., 2 figs., 20 refs

  11. Thinning to improve growth, bole quality, and forest health in an Inonotus hispidus-infected, red oak-sweetgum stand in the Mississippi Delta: 10-year results

    Science.gov (United States)

    James S. Meadows; Theodor D. Leininger; David Montwé; T. Evan Nebeker

    2013-01-01

    A 55-year-old red oak-sweetgum (Quercus spp.- Liquidambar styraciflua) stand on the Delta National Forest in western Mississippi was subjected to a combination of low thinning and improvement cutting in 1997. Special emphasis was placed on removing all red oaks infected with Inonotus hispidus, a canker decay...

  12. Dynamics of vegetation and soils of oak/saw palmetto scrub after fire: Observations from permanent transects

    Science.gov (United States)

    Schmalzer, Paul A.; Hinkle, G. Ross

    1991-01-01

    Ten permanent 15 m transects previously established in two oak/saw palmetto scrub stands burned in December 1986, while two transects remained unburned. Vegetation in the greater than 0.5 m and the less than 0.5 m layers on these transects was sampled at 6, 12, 18, 24, and 36 months postburn and determined structural features of the vegetation (height, percent bare ground, total cover). The vegetation data were analyzed from each sampling by height layer using detrended correspondence analysis ordination. Vegetation data for the greater than 0.5 m layer for the entire time sequence were combined and analyzed using detrended correspondence analysis ordination. Soils were sampled at 6, 12, 18, and 24 months postburn and analyzed for pH, conductivity, organic matter, exchangeable cations (Ca, Mg, K, Na), NO3-N, NH4-N, Al, available metals (Cu, Fe, Mn, Zn), and PO4-P. Shrub species recovered at different rates postfire with saw palmetto reestablishing cover greater than 0.5 m within one year, but the scrub oaks had not returned to preburn cover greater than 0.5 m in 3 years after the fire. These differences in growth rates resulted in dominance shifts after the fire with saw palmetto increasing relative to the scrub oaks. Overall changes in species richness were minor, although changes occurred in species richness by height layers due to different growth rates. Soils of well drained and poorly drained sites differed markedly. Soil responses to the fire appeared minor. Soil pH increased at 6 and 12 months postfire; calcium increased at 6 months postburn. Nitrate-nitrogen increased at 12 months postburn. Low values of conductivity, PO4-P, Mg, K, Na, and Fe at 12 months postburn may be related to heavy rainfall the preceding month. Seasonal variability in some soil parameters appeared to occur.

  13. Seeding and planting upland oaks

    Science.gov (United States)

    1989-01-01

    Oaks can be planted or seeded in uplands to: (1) afforest old fields, strip-mined areas, or other areas devoid of trees, and (2) supplement natural reproduction within existing forests. Planting is usually more successful than direct seeding. But even under good conditions survival and growth of planted oak has been considerably poorer than with conifers and other...

  14. Behavioral assumptions of conservation policy: conserving oak habitat on family-forest land in the Willamette Valley, Oregon

    Science.gov (United States)

    A. Paige Fischer; John C. Bliss

    2008-01-01

    Designing policies that harness the motivations of landowners is essential for conserving threatened habitats on private lands. Our goal was to understand how to apply ethnographic information about family-forest owners to the design of conservation policy for Oregon white oak (Quercus garryana) in the Willamette Valley, Oregon (U.S.A.). We examined...

  15. Habitat preferences of oak-feeding xylophagous beetles in a temperate woodland: implications for forest history and management

    Czech Academy of Sciences Publication Activity Database

    Vodka, Štěpán; Konvička, Martin; Čížek, Lukáš

    2009-01-01

    Roč. 13, č. 5 (2009), s. 553-562 ISSN 1366-638X R&D Projects: GA AV ČR KJB600960705; GA MŠk LC06073 Institutional research plan: CEZ:AV0Z50070508 Keywords : biodiversity conservation * forest management * oak Subject RIV: EH - Ecology, Behaviour Impact factor: 1.842, year: 2009

  16. 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.

  17. Resource use and efficiency, and stomatal responses to environmental drivers of oak and pine species in an Atlantic Coastal Plain forest

    Science.gov (United States)

    Heidi J. Renninger; Nicholas J. Carlo; Kenneth L. Clark; Karina V.R. Schäfer

    2015-01-01

    Pine-oak ecosystems are globally distributed even though differences in anatomy and leaf habit between many co-occurring oaks and pines suggest different strategies for resource use, efficiency and stomatal behavior. The New Jersey Pinelands contain sandy soils with low water- and nutrient-holding capacity providing an opportunity to examine trade-offs in resource...

  18. 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.

  19. 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...

  20. BOREAS TE-5 Soil Respiration Data

    Science.gov (United States)

    Hall, Forrest G. (Editor); Curd, Shelaine (Editor); Ehleriinger, Jim; Brooks, J. Renee; Flanagan, Larry

    2000-01-01

    The BOREAS TE-5 team collected measurements in the NSA and SSA on gas exchange, gas composition, and tree growth. Soil respiration data were collected from 26-May-94 to 07-Sep-94 in the BOREAS NSA and SSA to compare the soil respiration rates in different forest sites using a LI-COR 6200 soil respiration chamber (model 6299). The data are stored in tabular ASCII files. The data files are available on a CD-ROM (see document number 20010000884), or from the Oak Ridge National Laboratory (ORNL) Distrobuted Activity Archive Center (DAAC).

  1. A Matrix Transition Model for an Uneven-Aged, Oak-Hickory Forest in the Missouri Ozark Highlands

    Science.gov (United States)

    James R. Lootens; David R. Larsen; Edward F. Loewenstein

    1999-01-01

    We present a matrix growth model for an uneven-aged, oak-hickory forest in the Ozark Highlands of Missouri. The model was developed to predict ingrowth, growth of surviving trees, and mortality by diameter class for a five-year period. Tree removal from management activities is accounted for in the model. We evaluated a progression of models from a static, fixed-...

  2. 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.

  3. Winning and losing tree species of reassembly in Minnesota's mixed and broadleaf forests.

    Directory of Open Access Journals (Sweden)

    Brice B Hanberry

    Full Text Available We examined reassembly of winning and losing tree species, species traits including shade and fire tolerance, and associated disturbance filters and forest ecosystem types due to rapid forest change in the Great Lakes region since 1850. We identified winning and losing species by changes in composition, distribution, and site factors between historical and current surveys in Minnesota's mixed and broadleaf forests. In the Laurentian Mixed Forest, shade-intolerant aspen replaced shade-intolerant tamarack as the most dominant tree species. Fire-tolerant white pine and jack pine decreased, whereas shade-tolerant ashes, maples, and white cedar increased. In the Eastern Broadleaf Forest, fire-tolerant white oaks and red oaks decreased, while shade-tolerant ashes, American basswood, and maples increased. Tamarack, pines, and oaks have become restricted to sites with either wetter or sandier and drier soils due to increases in aspen and shade-tolerant, fire-sensitive species on mesic sites. The proportion of shade-tolerant species increased in both regions, but selective harvest reduced the applicability of functional groups alone to specify winners and losers. Harvest and existing forestry practices supported aspen dominance in mixed forests, although without aspen forestry and with fire suppression, mixed forests will transition to a greater composition of shade-tolerant species, converging to forests similar to broadleaf forests. A functional group framework provided a perspective of winning and losing species and traits, selective filters, and forest ecosystems that can be generalized to other regions, regardless of species identity.

  4. Winning and losing tree species of reassembly in Minnesota's mixed and broadleaf forests.

    Science.gov (United States)

    Hanberry, Brice B; Palik, Brian J; He, Hong S

    2013-01-01

    We examined reassembly of winning and losing tree species, species traits including shade and fire tolerance, and associated disturbance filters and forest ecosystem types due to rapid forest change in the Great Lakes region since 1850. We identified winning and losing species by changes in composition, distribution, and site factors between historical and current surveys in Minnesota's mixed and broadleaf forests. In the Laurentian Mixed Forest, shade-intolerant aspen replaced shade-intolerant tamarack as the most dominant tree species. Fire-tolerant white pine and jack pine decreased, whereas shade-tolerant ashes, maples, and white cedar increased. In the Eastern Broadleaf Forest, fire-tolerant white oaks and red oaks decreased, while shade-tolerant ashes, American basswood, and maples increased. Tamarack, pines, and oaks have become restricted to sites with either wetter or sandier and drier soils due to increases in aspen and shade-tolerant, fire-sensitive species on mesic sites. The proportion of shade-tolerant species increased in both regions, but selective harvest reduced the applicability of functional groups alone to specify winners and losers. Harvest and existing forestry practices supported aspen dominance in mixed forests, although without aspen forestry and with fire suppression, mixed forests will transition to a greater composition of shade-tolerant species, converging to forests similar to broadleaf forests. A functional group framework provided a perspective of winning and losing species and traits, selective filters, and forest ecosystems that can be generalized to other regions, regardless of species identity.

  5. Spatial pattern of tree diversity and evenness across forest types in Majella National Park, Italy

    Directory of Open Access Journals (Sweden)

    Mohammad Redowan

    2015-09-01

    Full Text Available Background Estimation of tree diversity at broader scale is important for conservation planning. Tree diversity should be measured and understood in terms of diversity and evenness, two integral components to describe the structure of a biological community. Variation of the tree diversity and evenness with elevation, topographic relief, aspect, terrain shape, slope, soil nutrient, solar radiation etc. are well documented. Methods Present study explores the variation of tree diversity (measured as Shannon diversity and evenness indices of Majella National Park, Italy with five available forest types namely evergreen oak woods, deciduous oak woods, black/aleppo pine stands, hop-hornbeam forest and beech forest, using satellite, environmental and field data. Results Hop-hornbeam forest was found to be most diverse and even while evergreen Oak woods was the lowest diverse and even. Diversity and evenness of forest types were concurrent to each other i.e. forest type which was more diverse was also more even. As a broad pattern, majority portion of the study area belonged to medium diversity and high evenness class. Conclusions Satellite images and other GIS data proved useful tools in monitoring variation of tree diversity and evenness across various forest types. Present study findings may have implications in prioritizing conservation zones of high tree diversity at Majella.

  6. 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...

  7. 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.

  8. 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

  9. Intraspecific variation in host susceptibility and climatic factors mediate epidemics of sudden oak death in western US forests

    Science.gov (United States)

    D. Huberli; K.J. Hayden; M. Calver; M. Garbelotto

    2011-01-01

    Umbellularia californica is one of the key infectious hosts of the exotic Phytophthora ramorum, which causes sudden oak death (SOD) in California and Oregon forests. This study provides a comprehensive analysis of the epidemiologically relevant parameters for SOD in California and southern Oregon, including potential differences between the two...

  10. 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

  11. Soil N chemistry in oak forests along a nitrogen deposition gradient

    DEFF Research Database (Denmark)

    Nilsson, Lars Ola; Wallander, Håkan; Bååth, Erland

    2006-01-01

    values of grass and uppermost soil layers indicate increased nitrification rates in high N deposition sites, but no large downward movements of NO3 in these soils. Only a few sites had NO-3 concentrations exceeding 1 mg N l-¹ in soil solution at 50 cm depth, which showed that N deposition to these acid...

  12. Characterization and inventory of contaminants in WAG 2 floodplain soils of White Oak Creek

    International Nuclear Information System (INIS)

    Ford, C.J.; Nyquist, J.E.; Purucker, S.T.; Burgoa, B.B.; Winterfield, R.F.

    1997-01-01

    A remedial investigation was conducted to determine the extent and type of contamination in the floodplain soils of Waste Area Grouping (WAG) 2, in conjunction with environmental restoration activities at the US Department of Energy (DOE) Oak Ridge Reservation (ORR). WAG 2 is located downstream from the main Oak Ridge National Laboratory (ORNL) plant area. As a result of past, present, and potential future releases of hazardous substances to the environment, the ORR was placed on the National Priorities List in December 1989. Sites on this list must be investigated to determine if remedial actions are possible. This report documents the findings of the remedial investigation of the WAG 2 floodplain soils by (1) presenting the characterization and inventory of contaminants, (2) comparing the walkover survey data to quantitative gamma-emitting radionuclide data, and (3) presenting an assessment of human health risk from exposure to these soils. Contaminant characterization results indicated that the primary contaminants in the WAG 2 floodplain are the gamma-emitting radionuclides 137 Cs and 60 Co, although cobalt activity levels are 1/25th or less than those of cesium. Inorganic contaminants discussed in this report were limited to those contributing significantly to human exposure: antimony, barium, chromium(IV), manganese, mercury, and nickel

  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. A Redescription of Acanthocreagris iranica (Pseudoscorpiones, Neobisiidae Inhabiting Soil Under Oak Trees in Zagros Forest, Western Iran

    Directory of Open Access Journals (Sweden)

    Nassirkhani M.

    2017-04-01

    Full Text Available During study on soil mesofauna in Choqa Sabz Forest and Dalab Protected Area in Ilam Province (western Iran, the following pseudoscorpions belonging to four families were collected and identified: Chthonius (Chthonius shelkovnikovi Redikorzev, 1930, Chthonius (Ephippiochthonius negarinae Nassirkhani and Vafai, 2015, Paramenthus nanus Mahnert, 2007, Cardiolpium asiaticum (Dashdamirov, 1990, and Acanthocreagris iranica Beier, in Mahnert 1976. All of these species are new to the fauna of western Iran. In this survey, the adults of A. iranica collected from Ilam and Lorestan Provinces are redescribed and figured. Additionally, its tritonymph and deutonymph are briefly described.

  15. [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.

  16. 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.

  17. Water Balance Study of a Groundwater-dependent Oak Forest

    Directory of Open Access Journals (Sweden)

    MÓRICZ, Norbert

    2010-01-01

    Full Text Available The objectives of this study were (1 to estimate the water balance components of an oak standby calibrating a Hydrus 1-D model, (2 to determine the groundwater consumption by the water tablefluctuation method and (3 to compare the results of the modelling with a remote-sensing based estimation.Model simulation described the observed soil moisture and groundwater level relatively well, theroot mean square errors varied between 12.0 and 14.9% for the soil moisture measurements and 5.0%for the groundwater level. Groundwater consumption was estimated also by the water table fluctuationmethod, which provided slightly different groundwater consumption rates than estimated by theHydrus model simulation. The simulated evapotranspiration was compared with results of a remotesensingbased estimation using the surface temperature database of MODIS.According to the Hydrus model, the estimated evapotranspiration resulted from transpiration(73%, interception loss (23% and soil surface evaporation (4% in the two-year study period. Theproportion of groundwater consumption was 58% of the total transpiration. During the dry growingseason of 2007 the groundwater consumption was significant with 66% of the total transpiration.Water supply from groundwater was found to be less important in the wet growing season of 2008with 50%. The remote-sensing based estimation of evapotranspiration was about 4% lower than themodel based results of nearby comparable sites.

  18. 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.

  19. 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...

  20. 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.

  1. Winning and Losing Tree Species of Reassembly in Minnesota’s Mixed and Broadleaf Forests

    Science.gov (United States)

    Hanberry, Brice B.; Palik, Brian J.; He, Hong S.

    2013-01-01

    We examined reassembly of winning and losing tree species, species traits including shade and fire tolerance, and associated disturbance filters and forest ecosystem types due to rapid forest change in the Great Lakes region since 1850. We identified winning and losing species by changes in composition, distribution, and site factors between historical and current surveys in Minnesota’s mixed and broadleaf forests. In the Laurentian Mixed Forest, shade-intolerant aspen replaced shade-intolerant tamarack as the most dominant tree species. Fire-tolerant white pine and jack pine decreased, whereas shade-tolerant ashes, maples, and white cedar increased. In the Eastern Broadleaf Forest, fire-tolerant white oaks and red oaks decreased, while shade-tolerant ashes, American basswood, and maples increased. Tamarack, pines, and oaks have become restricted to sites with either wetter or sandier and drier soils due to increases in aspen and shade-tolerant, fire-sensitive species on mesic sites. The proportion of shade-tolerant species increased in both regions, but selective harvest reduced the applicability of functional groups alone to specify winners and losers. Harvest and existing forestry practices supported aspen dominance in mixed forests, although without aspen forestry and with fire suppression, mixed forests will transition to a greater composition of shade-tolerant species, converging to forests similar to broadleaf forests. A functional group framework provided a perspective of winning and losing species and traits, selective filters, and forest ecosystems that can be generalized to other regions, regardless of species identity. PMID:23613911

  2. Occurrence of an exotic earthworm (Amynthas agrestis) in undisturbed soils of the southern Appalachian Mountains, USA

    Science.gov (United States)

    Mac. A. Callaham; Paul F. Hendrix; Ross J. Phillips

    2003-01-01

    This study documents the occurrence of an aggressive invasive earthworm species in undisturbed forest soils of the southern Appalachian Mountains of northern Georgia, USA. Earthworms were sorted from samples collected in pitfall traps that had been set in mature, mesic oak-hickory forests in remote, high elevation, locations across northern Georgia. Specimens were...

  3. Hydrologic Impacts of Oak Harvesting and Evaluation of the Modified Universal Soil Loss Equation

    Science.gov (United States)

    Charlette R. Epifanio; Michael J. Singer; Xiaohong Huang

    1991-01-01

    Two Sierra foothill watersheds were monitored to learn what effects selective oak removal would have on watershed hydrology and water quality. We also used the data to generate sediment rating curves and evaluate the modified universal soil loss equation (MUSLE). Annual sediment rating curves better accounted for the variability in precipitation events from year to...

  4. Soil Respiration And Respiration Partitioning In An Oak-Savannah With A History Of Fertilization

    Science.gov (United States)

    Morris, K. A.; Nair, R.; Schrumpf, M.; Migliavacca, M.

    2017-12-01

    Soil respiration is a combination of autotrophic and heterotrophic components. These components have different controls and structurally complex ecosystems such as oak-savannahs offer an opportunity to study strongly contrasting conditions (ie., soil from under trees versus open areas) in an environment with similar soil mineralogy and climatic patterns. To measure respiration coming from plant roots, fungal hyphae, and free-living microbes we established stations of soil cores comprised of three selectively permeable meshes under tree canopies and in open grassy areas of a Holm Oak (Quercus ilex) savannah in Extremadura, Spain. Large plots of this ecosystem had previously been fertilized as part of a stoichiometeric imbalance study (in 2015). Stations were installed in Dec. 2016 within four plots; control, N added, P added, and N+P added. Respiration from cores was measured in campaigns at key phenological stages with a portable Li-Cor 8100A unit. Six months after installation > 50% of soil respiration was attributable to free-living microbes. There is a persistent effect of the prior fertilization, resulting in increased soil respiration in open areas regardless of fertilizer type, while respiration from under tree canopies had a varied response. Soil under tree canopies showed distinct sensitivity to stoichiometric imbalance, meaning that addition of N or P alone either did not change respiration or decreased it slightly, while N+P stimulated respiration. We determined that respiration from free-living microbes is a major component of soil respiration even in the most active plant growing season. However, because of the lag between the time of fertilization and the time of measurement, it not possible to say whether treatment responses are due solely to nutrient status of the soil or whether changes in plant biomass and species composition also play a role. Additional work planned at the site will shed light on this uncertainty as well as the contribution of

  5. 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

  6. 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.

  7. 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.

  8. [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.

  9. Microbial properties and litter and soil nutrients after two prescribed fires in developing savannas in an upland Missouri Ozark Forest

    Science.gov (United States)

    Felix, Jr. Ponder; Mahasin Tadros; Edward F. Loewenstein

    2009-01-01

    On some landscapes periodic fire may be necessary to develop and maintain oak-dominated savannas. We studied the effects of two annual prescribed burns to determine their effect on microbial activity and soil and litter nutrients 1 year after the last burn. Surface litter and soil from the upper 0?5 cm soil layer in three developing savannas (oak-hickory, ...

  10. 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.

  11. 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).

  12. 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...

  13. Sudden oak death-caused changes to surface fuel loading and potential fire behavior in Douglas-fir-tanoak forests

    Science.gov (United States)

    Y.S. Valachovic; C.A. Lee; H. Scanlon; J.M. Varner; R. Glebocki; B.D. Graham; D.M. Rizzo

    2011-01-01

    We compared stand structure and fuel loading in northwestern California forests invaded by Phytophthora ramorum, the cause of sudden oak death, to assess whether the continued presence of this pathogen alters surface fuel loading and potential fire behavior in ways that may encumber future firefighting response. To attempt to account for these...

  14. Photo guide for estimating fuel loading and fire behavior in mixed-oak forests of the Mid-Atlantic Region

    Science.gov (United States)

    Patrick H. Brose

    2009-01-01

    A field guide of 45 pairs of photographs depicting ericaceous shrub, leaf litter, and logging slash fuel types of eastern oak forests and observed fire behavior of these fuel types during prescribed burning. The guide contains instructions on how to use the photo guide to choose appropriate fuel models for prescribed fire planning.

  15. 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.

  16. 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.

  17. 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

  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. Effects of acid rain and liming on the enchytraeid fauna in forest soils

    International Nuclear Information System (INIS)

    Graefe, U.

    1989-01-01

    The development of the enchytraeid community has been observed in a Solling beech forest over a period of 11 years. Eight out of 18 formerly established species have disappeared in one decade. The connection to soil chemical changes due to atmospheric deposition is discussed. A comparison of adjoining beech and spruce stands revealed considerably lower species numbers under spruce. The community under beech is developing in the direction of the species community in the spruce stand. Liming affects changes in the dominance structure. Mesophilic species are favoured, acidophilic are repressed. In an oak-beech stand near Hamburg even the recolonization by previously absent species was observed. Liming experiments with 25, 50 and 100 dt CaCO 3 /ha showed decreasing total abundance of enchytraeids proportional to the amount of lime. Species number, diversity and evenness increased with lime treatments up to 50 dt/ha. (orig.)

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

    International Nuclear Information System (INIS)

    Berg, Mitchell T.; Shuman, Larry J.

    1995-01-01

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

  1. Examining fire-induced forest changes using novel remote sensing technique: a case study in a mixed pine-oak forest

    Science.gov (United States)

    Meng, R.; Wu, J.; Zhao, F. R.; Cook, B.; Hanavan, R. P.; Serbin, S.

    2017-12-01

    Fire-induced forest changes has long been a central focus for forest ecology and global carbon cycling studies, and is becoming a pressing issue for global change biologists particularly with the projected increases in the frequency and intensity of fire with a warmer and drier climate. Compared with time-consuming and labor intensive field-based approaches, remote sensing offers a promising way to efficiently assess fire effects and monitor post-fire forest responses across a range of spatial and temporal scales. However, traditional remote sensing studies relying on simple optical spectral indices or coarse resolution imagery still face a number of technical challenges, including confusion or contamination of the signal by understory dynamics and mixed pixels with moderate to coarse resolution data (>= 30 m). As such, traditional remote sensing may not meet the increasing demand for more ecologically-meaningful monitoring and quantitation of fire-induced forest changes. Here we examined the use of novel remote sensing technique (i.e. airborne imaging spectroscopy and LiDAR measurement, very high spatial resolution (VHR) space-borne multi-spectral measurement, and high temporal-spatial resolution UAS-based (Unmanned Aerial System) imagery), in combination with field and phenocam measurements to map forest burn severity across spatial scales, quantify crown-scale post-fire forest recovery rate, and track fire-induced phenology changes in the burned areas. We focused on a mixed pine-oak forest undergoing multiple fire disturbances for the past several years in Long Island, NY as a case study. We demonstrate that (1) forest burn severity mapping from VHR remote sensing measurement can capture crown-scale heterogeneous fire patterns over large-scale; (2) the combination of VHR optical and structural measurements provides an efficient means to remotely sense species-level post-fire forest responses; (3) the UAS-based remote sensing enables monitoring of fire

  2. Modeling the potential role of a forest ecosystem in phytostabilization and phytoextraction of 90Sr at a contaminated watershed

    International Nuclear Information System (INIS)

    Garten, C.T. Jr.

    1999-01-01

    The behavior of 90 Sr at forest sites in the White Oak Creek watershed, near Oak Ridge, Tennessee, was simulated with a simple, site-specific, multicompartment model that linked biomass and element cycling dynamics. The model was used to predict the role of forest cover in mitigating hydrologic losses of 90 Sr from contaminated soils (i.e. phytostabilization) under conditions where contaminant transport is governed mainly by shallow subsurface flow. The model was also used to predict the removal of 90 Sr from soil (i.e. phytoextraction) through the growth and harvest of short rotation woody crops over a period of 30 years. Simulations with the model indicated that (1) forest preservation on the watershed is a form of phytostabilization because forest cover helps to minimize hydrologic losses of 90 Sr and (2) an attempt to significantly reduce amounts of 90 Sr in soil through phytoextraction would be unsuccessful. Over a period of 30 years, and under various management strategies, the model predicted that 90 Sr initially present in soil at a contaminated site was lost through hydrologic transport and <53% was lost by radioactive decay. Phytostabilization may be important in the management of radioactive land when issues like waste minimization and pollution prevention affect the selection of technologies to be used in environmental restoration. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)

  3. Transpiration of montane Pinus sylvestris L. and Quercus pubescens Willd. forest stands measured with sap flow sensors in NE Spain

    Directory of Open Access Journals (Sweden)

    R. Poyatos

    2005-01-01

    Full Text Available Stand transpiration was measured during the 2003 and 2004 growing seasons using heat dissipation sap flow sensors in a Scots pine (Pinus sylvestris L. and a pubescent oak (Quercus pubescens Willd. forests located in a montane area of the Eastern Pyrenees (NE Spain. The first aim of the study was to assess the differences in quantitative estimates of transpiration (Ec and the response to evaporative demand of the two stands. Over the studied period of 2003, characterised by a severe drought episode during the summer, the oak stand (Ec was only 110 mm compared to the 239 mm transpired by the Scots pine stand, although the ratio of transpiration to reference evapotranspiration (Ec/ET0 in the oak stand compares well with the expected values predicted for low leaf area index (LAI oak forests in southern Europe. Scots pine showed a strong reduction in (Ec/ET0 as the drought developed, whereas pubescent oak was less affected by soil moisture deficits in the upper soil. As a second objective, and given the contrasting meteorological conditions between 2003 and 2004 summer periods, the interannual variability of transpiration was studied in the Scots pine plot. Rainfall during the summer months (June-September in 2003 was almost 40% less than in the same interval in 2004. Accordingly, transpiration was also reduced about 25% in 2003. Finally, Scots pine data from 2003 and 2004 was used to calibrate a simple transpiration model using ET0 and soil moisture deficit (SMD as input variables, and implicitly including stomatal responses to high vapour pressure deficits (Dd and soil water status.

  4. Ligninolytic Activity at 0 °C of Fungi on Oak Leaves Under Snow Cover in a Mixed Forest in Japan.

    Science.gov (United States)

    Miyamoto, Toshizumi; Koda, Keiichi; Kawaguchi, Arata; Uraki, Yasumitsu

    2017-08-01

    Despite the importance of litter decomposition under snow cover in boreal forests and tundra, very little is known regarding the characteristics and functions of litter-decomposing fungi adapted to the cold climate. We investigated the decomposition of oak leaves in a heavy snowfall forest region of Japan. The rate of litter weight loss reached 26.5% during the snow cover period for 7 months and accounted for 64.6% of the annual loss (41.1%). Although no statistically significant lignin loss was detected, decolourization portions of oak leaf litter, which was attributable to the activities of ligninolytic fungi, were observed during snow cover period. This suggests that fungi involved in litter decomposition can produce extracellular enzymes to degrade lignin that remain active at 0 °C. Fungi were isolated from oak leaves collected from the forest floor under the snow layer. One hundred and sixty-six strains were isolated and classified into 33 operational taxonomic units (OTUs) based on culture characteristics and nuclear rDNA internal transcribed spacer (ITS) region sequences. To test the ability to degrade lignin, the production of extracellular phenoloxidases by isolates was quantified at 0 °C. Ten OTUs (9 Ascomycota and 1 Basidiomycota) of fungi exhibited mycelial growth and ligninolytic activity. These results suggested that some litter-decomposing fungi that had the potential to degrade lignin at 0 °C significantly contribute to litter decomposition under snow cover.

  5. Fine root dynamics for forests on contrasting soils in the Colombian Amazon

    Directory of Open Access Journals (Sweden)

    E. M. Jiménez

    2009-12-01

    Full Text Available It has been hypothesized that as soil fertility increases, the amount of carbon allocated to below-ground production (fine roots should decrease. To evaluate this hypothesis, we measured the standing crop fine root mass and the production of fine roots (<2 mm by two methods: (1 ingrowth cores and, (2 sequential soil coring, during 2.2 years in two lowland forests growing on different soils types in the Colombian Amazon. Differences of soil resources were defined by the type and physical and chemical properties of soil: a forest on clay loam soil (Endostagnic Plinthosol at the Amacayacu National Natural Park and, the other on white sand (Ortseinc Podzol at the Zafire Biological Station, located in the Forest Reservation of the Calderón River. We found that the standing crop fine root mass and the production was significantly different between soil depths (0–10 and 10–20 cm and also between forests. The loamy sand forest allocated more carbon to fine roots than the clay loam forest with the production in loamy sand forest twice (mean±standard error=2.98±0.36 and 3.33±0.69 Mg C ha−1 yr−1, method 1 and 2, respectively as much as for the more fertile loamy soil forest (1.51±0.14, method 1, and from 1.03±0.31 to 1.36±0.23 Mg C ha−1 yr−1, method 2. Similarly, the average of standing crop fine root mass was higher in the white-sands forest (10.94±0.33 Mg C ha−1 as compared to the forest on the more fertile soil (from 3.04±0.15 to 3.64±0.18 Mg C ha−1. The standing crop fine root mass also showed a temporal pattern related to rainfall, with the production of fine roots decreasing substantially in the dry period of the year 2005. These results suggest that soil resources may play an important role in patterns of carbon allocation to the production of fine roots in these forests as the proportion of carbon allocated to above- and below-ground organs is different

  6. 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

  7. 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%

  8. 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.

  9. Litter Species Composition and Topographic Effects on Fuels and Modeled Fire Behavior in an Oak-Hickory Forest in the Eastern USA.

    Science.gov (United States)

    Dickinson, Matthew B; Hutchinson, Todd F; Dietenberger, Mark; Matt, Frederick; Peters, Matthew P

    2016-01-01

    Mesophytic species (esp. Acer rubrum) are increasingly replacing oaks (Quercus spp.) in fire-suppressed, deciduous oak-hickory forests of the eastern US. A pivotal hypothesis is that fuel beds derived from mesophytic litter are less likely than beds derived from oak litter to carry a fire and, if they do, are more likely to burn at lower intensities. Species effects, however, are confounded by topographic gradients that affect overstory composition and fuel bed decomposition. To examine the separate and combined effects of litter species composition and topography on surface fuel beds, we conducted a common garden experiment in oak-hickory forests of the Ohio Hills. Each common garden included beds composed of mostly oak and mostly maple litter, representative of oak- and maple-dominated stands, respectively, and a mixture of the two. Beds were replenished each fall for four years. Common gardens (N = 16) were established at four topographic positions (ridges, benches on south- and northeast-facing slopes, and stream terraces) at each of four sites. Litter source and topographic position had largely independent effects on fuel beds and modeled fire dynamics after four years of development. Loading (kg m-2) of the upper litter layer (L), the layer that primarily supports flaming spread, was least in more mesic landscape positions and for maple beds, implying greater decomposition rates for those situations. Bulk density in the L layer (kg m-3) was least for oak beds which, along with higher loading, would promote fire spread and fireline intensity. Loading and bulk density of the combined fermentation and humic (FH) layers were least on stream terrace positions but were not related to species. Litter- and FH-layer moistures during a 5-day dry-down period after a rain event were affected by time and topographic effects while litter source effects were not evident. Characteristics of flaming combustion determined with a cone calorimeter pointed to greater fireline

  10. Influence of climate and land use on historical surface fires in pine-oak forests, Sierra Madre Occidental, Mexico

    Science.gov (United States)

    Emily K. Heyerdahl; Ernesto Alvarado

    2003-01-01

    The rugged mountains of the Sierra Madre Occidental, in north-central Mexico, support a mosaic of diverse ecosystems. Of these, the high-elevation, temperate pine-oak forests are ecologically significant for their extensiveness and biodiversity. They cover nearly half the land area in the states of Durango and Chihuahua (42%), and comprise a similar percentage of the...

  11. 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...

  12. 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

  13. 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...

  14. 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.

  15. Winter climate controls soil carbon dynamics during summer in boreal forests

    International Nuclear Information System (INIS)

    Haei, Mahsa; Öquist, Mats G; Ilstedt, Ulrik; Laudon, Hjalmar; Kreyling, Juergen

    2013-01-01

    Boreal forests, characterized by distinct winter seasons, store a large proportion of the global terrestrial carbon (C) pool. We studied summer soil C-dynamics in a boreal forest in northern Sweden using a seven-year experimental manipulation of soil frost. We found that winter soil climate conditions play a major role in controlling the dissolution/mineralization of soil organic-C in the following summer season. Intensified soil frost led to significantly higher concentrations of dissolved organic carbon (DOC). Intensified soil frost also led to higher rates of basal heterotrophic CO 2 production in surface soil samples. However, frost-induced decline in the in situ soil CO 2 concentrations in summer suggests a substantial decline in root and/or plant associated rhizosphere CO 2 production, which overrides the effects of increased heterotrophic CO 2 production. Thus, colder winter soils, as a result of reduced snow cover, can substantially alter C-dynamics in boreal forests by reducing summer soil CO 2 efflux, and increasing DOC losses. (letter)

  16. 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...

  17. [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

  18. 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.

  19. A meta-analysis of soil microbial biomass responses to forest disturbances

    Directory of Open Access Journals (Sweden)

    Sandra Robin Holden

    2013-06-01

    Full Text Available Climate warming is likely to increase the frequency and severity of forest disturbances, with uncertain consequences for soil microbial communities and their contribution to ecosystem C dynamics. To address this uncertainty, we conducted a meta-analysis of 139 published soil microbial responses to forest disturbances. These disturbances included abiotic (fire, harvesting, storm and biotic (insect, pathogen disturbances. We hypothesized that soil microbial biomass would decline following forest disturbances, but that abiotic disturbances would elicit greater reductions in microbial biomass than biotic disturbances. In support of this hypothesis, across all published studies, disturbances reduced soil microbial biomass by an average of 29.4%. However, microbial responses differed between abiotic and biotic disturbances. Microbial responses were significantly negative following fires, harvest, and storms (48.7%, 19.1%, and 41.7% reductions in microbial biomass, respectively. In contrast, changes in soil microbial biomass following insect infestation and pathogen-induced tree mortality were non-significant, although biotic disturbances were poorly represented in the literature. When measured separately, fungal and bacterial responses to disturbances mirrored the response of the microbial community as a whole. Changes in microbial abundance following disturbance were significantly positively correlated with changes in microbial respiration. We propose that the differential effect of abiotic and biotic disturbances on microbial biomass may be attributable to differences in soil disruption and organic C removal from forests among disturbance types. Altogether, these results suggest that abiotic forest disturbances may significantly decrease soil microbial abundance, with corresponding consequences for microbial respiration. Further studies are needed on the effect of biotic disturbances on forest soil microbial communities and soil C dynamics.

  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. Plant and bird diversity in natural forests and in native and exotic plantations in NW Portugal

    Science.gov (United States)

    Proença, Vânia M.; Pereira, Henrique M.; Guilherme, João; Vicente, Luís

    2010-03-01

    Forest ecosystems have been subjected to continuous dynamics between deforestation and forestation. Assessing the effects of these processes on biodiversity could be essential for conservation planning. We analyzed patterns of species richness, diversity and evenness of plants and birds in patches of natural forest of Quercus spp. and in stands of native Pinus pinaster and exotic Eucalyptus globulus in NW Portugal. We analyzed data of forest and non-forest species separately, at the intra-patch, patch and inter-patch scales. Forest plant richness, diversity and evenness were higher in oak forest than in pine and eucalypt plantations. In total, 52 species of forest plants were observed in oak forest, 33 in pine plantation and 28 in eucalypt plantation. Some forest species, such as Euphorbia dulcis, Omphalodes nitida and Eryngium juresianum, were exclusively or mostly observed in oak forest. Forest bird richness and diversity were higher in both oak and pine forests than in eucalypt forest; evenness did not differ among forests. In total, 16 species of forest birds were observed in oak forest, 18 in pine forest and 11 in eucalypt forest. Species such as Certhia brachydactyla, Sitta europaea and Dendrocopos major were common in oak and/or pine patches but were absent from eucalypt stands. Species-area relationships of forest plants and forest birds in oak patches had consistently a higher slope, at both the intra and inter-patch scales, than species-area relationships of forest species in plantations and non-forest species in oak forest. These findings demonstrate the importance of oak forest for the conservation of forest species diversity, pointing the need to conserve large areas of oak forest due to the apparent vulnerability of forest species to area loss. Additionally, diversity patterns in pine forest were intermediate between oak forest and eucalypt forest, suggesting that forest species patterns may be affected by forest naturalness.

  2. 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,...

  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. 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.

  5. Oak conservation and restoration on private forestlands: negotiating a social-ecological landscape.

    Science.gov (United States)

    Knoot, Tricia G; Schulte, Lisa A; Rickenbach, Mark

    2010-01-01

    In the midwestern United States, oak (Quercus spp.) forests are considered critical habitat for conserving biodiversity and are a declining resource. Ecological conditions, such as deer herbivory and competition from more mesic broad-leaved deciduous species, have been linked to poor oak regeneration. In the Midwest, where up to 90% of forestland is privately owned, a greater understanding of social dimensions of oak regeneration success is especially critical to designing effective restoration strategies. We sought to determine factors that serve as direct and indirect constraints to oak restoration and identify policy mechanisms that could improve the likelihood for restoration success. We conducted in-depth qualitative interviews with 32 natural resource professionals working in the Midwest Driftless Area. We found that most professionals anticipate that oak will remain only a component of the future forest. Furthermore, they identified the general unwillingness of landowners to adopt oak restoration practices as a primary driving force of regional forest change. The professionals pointed to interdependent ecological and social factors, occurring at various scales (e.g., economic cost of management, deer herbivory, and exurban residential development) as influencing landowner oak restoration decisions. Professionals emphasized the importance of government cost-share programs and long-term personal relationships to securing landowner acceptance of oak restoration practices. However, given finite societal resources, ecologically- and socially-targeted approaches were viewed as potential ways to optimize regional success.

  6. The epidemiology of sudden oak death in Oregon forests

    Science.gov (United States)

    Ebba K. Peterson

    2011-01-01

    The phytopathogen Phytophthora ramorum (Werres, DeCock & Man in't Veld), causal agent of Sudden Oak Death (SOD) of oaks (Quercus spp.) and tanoaks (Notholithocarpus densiflorus syn. Lithocarpus densiflorus...

  7. Elemental concentrations in foliage of red maple, red oak, and white oak in relation to atmospheric deposition in Pennsylvania

    Science.gov (United States)

    D. D. Davis; J. M. Skelly; B. L. Nash

    1995-01-01

    Foliage was sampled in June and late August-early September in 1988 and 1989 from the outer crowns of codominant red maple (Acer rubrum L.), northern red oak (Quercus rubra L.), and white oak (Q. alba L.) trees in forest stands along an atmospheric deposition gradient in north-central Pennsylvania. Leaf samples...

  8. 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.

  9. 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.

  10. 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.

  11. 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

  12. Soil carbon storage as influenced by tree cover in the Dehesa cork oak silvopasture of central-western Spain.

    Science.gov (United States)

    Howlett, David Scott; Moreno, Gerardo; Mosquera Losada, Maria Rosa; Nair, P K Ramachandran; Nair, Vimala D

    2011-07-01

    The extent of carbon (C) stored in soils depends on a number of factors including soil characteristics, climatic and other environmental conditions, and management practices. Such information, however, is lacking for silvopastoral systems in Spain. This study quantified the amounts of soil C stored at various depths (0-25, 25-50, 50-75, and 75-100 cm) under a Dehesa cork oak (Quercus suber L.) silvopasture at varying distances (2, 5, and 15 m) to trees. Soil C in the whole soil and three soil fractions (silvopastoral systems. The results also demonstrate the use of soil aggregate characteristics as better indicators of soil C sequestration potential and thus a tool for environmental monitoring.

  13. 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.

  14. Management of oak forests

    DEFF Research Database (Denmark)

    Löf, Magnus; Brunet, Jörg; Filyushkina, Anna

    2016-01-01

    timber production, habitats for biodiversity and cultural services, and the study analyses associated trade-offs and synergies. The three regimes were: intensive oak timber production (A), combined management for both timber production and biodiversity (B) and biodiversity conservation without management...... of wood production and cultural services. In contrast, Regime B provided a balanced delivery of timber production, biodiversity conservation and cultural services. We identified several stand-management options which provide comparatively synergistic outcomes in ecosystem services delivery. The use...

  15. Study of the sap-flow and related quantities of oak trees in field experiments

    International Nuclear Information System (INIS)

    Kanalas, P.; Olah, V.; Szoelloesi, E.; Meszaros, I.; Ander, I.; Fenyvesi, A.

    2009-01-01

    Complete text of publication follows. Climatology model calculations for the next decades in the Carpathian Basin predict more frequent occurrence of meteorological extremes and, especially, longer droughts with elevated average temperatures during the growing season. A drift of the transition zone between the wooden steppe and the forest regions is predicted, too, resulting in significant reduction and alteration of the climazonal forest communities in the mountainous regions. The aim of our project is obtaining information on the climatic sensitivity of the tree species in the sessile oak - Austrian oak forest stand of the Sikfoekut Project Long Term Ecological Research (LTER) area (Buekk Mountains, NE Hungary). 'Campaign-like' complex field measurements have been performed in contrasting vegetation seasons of 2007 and 2008. As a function of time, stomatal conductance and intensity of sap-flow and stem diameter of Quercus petraea and Quercus cerris trees were measured simultaneously with photosynthetic photon flux density (PPFD), atmospheric pressure, temperature and relative humidity and vapour pressure deficit (VPD) of air, precipitation and soil moisture. It was found that the two oak species of forest stand exhibit similar daily course of stomatal conductance in rainy periods. However, during drought stomatal conductance of Quercus cerris was higher, and after a transitional decrease around midday it exhibited a second maximum in late afternoon. In dry days after a maximum of stomatal conductance at early morning the stomatal closure of Quercus petraea was permanent which might result in 'carbon starvation' of trees if drought is too long. During rainy periods, sap-flow of both species changed in correlation with VPD. In dry period this correlation weakened especially in case of Quercus petraea but a stronger correlation of sap-flow maximum appeared with the decreasing soil moisture content. Quercus cerris showed smaller stem radial variation, than Quercus

  16. 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.

  17. Carbon Stocks of Fine Woody Debris in Coppice Oak Forests at Different Development Stages

    Directory of Open Access Journals (Sweden)

    Ender Makineci

    2017-06-01

    Full Text Available Dead woody debris is a significant component of the carbon cycle in forest ecosystems. This study was conducted in coppice-originated oak forests to determine carbon stocks of dead woody debris in addition to carbon stocks of different ecosystem compartments from the same area and forests which were formerly elucidated. Weight and carbon stocks of woody debris were determined with recent samplings and compared among development stages (diameter at breast height (DBH, D1.3m, namely small-diameter forests (SDF = 0–8 cm, medium diameter forests (MDF = 8–20 cm, and large-diameter forests (LDF = 20–36 cm. Total woody debris was collected in samplings; as bilateral diameters of all woody debris parts were less than 10 cm, all woody parts were in the “fine woody debris (FWD” class. The carbon concentrations of FWD were about 48% for all stages. Mass (0.78–4.92 Mg·ha−1 and carbon stocks (0.38–2.39 Mg·ha−1 of FWD were significantly (p > 0.05 different among development stages. FWD carbon stocks were observed to have significant correlation with D1.3m, age, basal area, and carbon stocks of aboveground biomass (Spearman rank correlation coefficients; 0.757, 0.735, 0.709, and 0.694, respectively. The most important effects on carbon budgets of fine woody debris were determined to be coppice management and intensive utilization. Also, national forestry management, treatments of traditional former coppice, and conversion to high forest were emphasized as having substantial effects.

  18. 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

  19. Regime shifts and weakened environmental gradients in open oak and pine ecosystems.

    Science.gov (United States)

    Hanberry, Brice B; Dey, Dan C; He, Hong S

    2012-01-01

    Fire suppression allows tree species that are intolerant of fire stress to increase their distribution, potentially resulting in disruption of historical species-environmental relationships. To measure changes between historical General Land Office surveys (1815 to 1850) and current USDA Forest Inventory and Assessment surveys (2004 to 2008), we compared composition, distribution, and site factors of 21 tree species or species groups in the Missouri Ozarks. We used 24 environmental variables and random forests as a classification method to model distributions. Eastern redcedar, elms, maples, and other fire-sensitive species have increased in dominance in oak forests, with concurrent reductions by oak species; specific changes varied by ecological subsection. Ordinations displayed loss of separation between formerly distinctive oak and fire-sensitive tree species groups. Distribution maps showed decreased presence of disturbance-dependent oak and pine species and increased presence of fire-sensitive species that generally expanded from subsections protected from fire along rivers to upland areas, except for eastern redcedar, which expanded into these subsections. Large scale differences in spatial gradients between past and present communities paralleled reduced influence of local topographic gradients in the varied relief of the Missouri Ozarks, as fire-sensitive species have moved to higher, drier, and sunnier sites away from riverine corridors. Due to changes in land use, landscapes in the Missouri Ozarks, eastern United States, and world-wide are changing from open oak and pine-dominated ecosystems to novel oak-mixed species forests, although at fine scales, forests are becoming more diverse in tree species today. Fire suppression weakened the influence by environmental gradients over species dominance, allowing succession from disturbance-dependent oaks to an alternative state of fire-sensitive species. Current and future research and conservation that rely on

  20. 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.

  1. 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

  2. Avian response to fire in pine–oak forests of Great Smoky Mountains National Park following decades of fire suppression

    Science.gov (United States)

    Rose, Eli T.; Simons, Theodore R.

    2016-01-01

    Fire suppression in southern Appalachian pine–oak forests during the past century dramatically altered the bird community. Fire return intervals decreased, resulting in local extirpation or population declines of many bird species adapted to post-fire plant communities. Within Great Smoky Mountains National Park, declines have been strongest for birds inhabiting xeric pine–oak forests that depend on frequent fire. The buildup of fuels after decades of fire suppression led to changes in the 1996 Great Smoky Mountains Fire Management Plan. Although fire return intervals remain well below historic levels, management changes have helped increase the amount of fire within the park over the past 20 years, providing an opportunity to study patterns of fire severity, time since burn, and bird occurrence. We combined avian point counts in burned and unburned areas with remote sensing indices of fire severity to infer temporal changes in bird occurrence for up to 28 years following fire. Using hierarchical linear models that account for the possibility of a species presence at a site when no individuals are detected, we developed occurrence models for 24 species: 13 occurred more frequently in burned areas, 2 occurred less frequently, and 9 showed no significant difference between burned and unburned areas. Within burned areas, the top models for each species included fire severity, time since burn, or both, suggesting that fire influenced patterns of species occurrence for all 24 species. Our findings suggest that no single fire management strategy will suit all species. To capture peak occupancy for the entire bird community within xeric pine–oak forests, at least 3 fire regimes may be necessary; one applying frequent low severity fire, another using infrequent low severity fire, and a third using infrequently applied high severity fire.

  3. Flood tolerance of oak seedlings from bottomland and upland sites

    Science.gov (United States)

    Michael P. Walsh; Jerry Van Sambeek; Mark Coggeshall; David. Gwaze

    2009-01-01

    Artificial regeneration of oak species in floodplains presents numerous challenges because of the seasonal flooding associated with these areas. Utilizing not only flood-tolerant oak species, but also flood tolerant seed sources of the oak species, may serve to enhance seedling survival and growth rates. Despite the importance of these factors to hardwood forest...

  4. 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

  5. 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.

  6. 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.

  7. 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.

  8. Changes in the dynamics of foliar N metabolites in oak saplings by drought and air warming depend on species and soil type.

    Directory of Open Access Journals (Sweden)

    Bin Hu

    Full Text Available Climate change poses direct or indirect influences on physiological mechanisms in plants. In particular, long living plants like trees have to cope with the predicted climate changes (i.e. drought and air warming during their life span. The present study aimed to quantify the consequences of simulated climate change for foliar N metabolites over a drought-rewetting-drought course. Saplings of three Central European oak species (i.e. Quercus robur, Q. petraea, Q. pubescens were tested on two different soil types (i.e. acidic and calcareous. Consecutive drought periods increased foliar amino acid-N and soluble protein-N concentrations at the expense of structural N in all three oak species. In addition, transient effects on foliar metabolite dynamics were observed over the drought-rewetting-drought course. The lowest levels of foliar soluble protein-N, amino acid-N and potassium cation with a minor response to drought and air warming were found in the oak species originating from the driest/warmest habitat (Q. pubescens compared to Q. robur and Q. petraea. Higher foliar osmolyte-N and potassium under drought and air warming were observed in all oak species when grown on calcareous versus acidic soil. These results indicate that species-specific differences in physiological mechanisms to compensate drought and elevated temperature are modified by soil acidity.

  9. Edge effects on N2O, NO and CH4 fluxes in two temperate forests.

    Science.gov (United States)

    Remy, Elyn; Gasche, Rainer; Kiese, Ralf; Wuyts, Karen; Verheyen, Kris; Boeckx, Pascal

    2017-01-01

    Forest ecosystems may act as sinks or sources of nitrogen (N) and carbon (C) compounds, such as the climate relevant trace gases nitrous oxide (N 2 O), nitric oxide (NO) and methane (CH 4 ). Forest edges, which catch more atmospheric deposition, have become important features in European landscapes and elsewhere. Here, we implemented a fully automated measuring system, comprising static and dynamic measuring chambers determining N 2 O, NO and CH 4 fluxes along an edge-to-interior transect in an oak (Q. robur) and a pine (P. nigra) forest in northern Belgium. Each forest was monitored during a 2-week measurement campaign with continuous measurements every 2h. NO emissions were 9-fold higher than N 2 O emissions. The fluxes of NO and CH 4 differed between forest edge and interior, but not for N 2 O. This edge effect was more pronounced in the oak than in the pine forest. In the oak forest, edges emitted less NO (on average 60%) and took up more CH 4 (on average 177%). This suggests that landscape structure can play a role in the atmospheric budgets of these climate relevant trace gases. Soil moisture variation between forest edge and interior was a key variable explaining the magnitude of NO and CH 4 fluxes in our measurement campaign. To better understand the environmental impact of N and C trace gas fluxes from forest edges, additional and long-term measurements in other forest edges are required. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. 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.

  11. 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...

  12. 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

  13. [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.

  14. A top-down approach of surface carbonyl sulfide exchange by a Mediterranean oak forest ecosystem in southern France

    Science.gov (United States)

    Belviso, Sauveur; Reiter, Ilja Marco; Loubet, Benjamin; Gros, Valérie; Lathière, Juliette; Montagne, David; Delmotte, Marc; Ramonet, Michel; Kalogridis, Cerise; Lebegue, Benjamin; Bonnaire, Nicolas; Kazan, Victor; Gauquelin, Thierry; Fernandez, Catherine; Genty, Bernard

    2016-12-01

    The role that soil, foliage, and atmospheric dynamics have on surface carbonyl sulfide (OCS) exchange in a Mediterranean forest ecosystem in southern France (the Oak Observatory at the Observatoire de Haute Provence, O3HP) was investigated in June of 2012 and 2013 with essentially a top-down approach. Atmospheric data suggest that the site is appropriate for estimating gross primary production (GPP) directly from eddy covariance measurements of OCS fluxes, but it is less adequate for scaling net ecosystem exchange (NEE) to GPP from observations of vertical gradients of OCS relative to CO2 during the daytime. Firstly, OCS and carbon dioxide (CO2) diurnal variations and vertical gradients show no net exchange of OCS at night when the carbon fluxes are dominated by ecosystem respiration. This contrasts with other oak woodland ecosystems of a Mediterranean climate, where nocturnal uptake of OCS by soil and/or vegetation has been observed. Since temperature, water, and organic carbon content of soil at the O3HP should favor the uptake of OCS, the lack of nocturnal net uptake would indicate that its gross consumption in soil is compensated for by emission processes that remain to be characterized. Secondly, the uptake of OCS during the photosynthetic period was characterized in two different ways. We measured ozone (O3) deposition velocities and estimated the partitioning of O3 deposition between stomatal and non-stomatal pathways before the start of a joint survey of OCS and O3 surface concentrations. We observed an increasing trend in the relative importance of the stomatal pathway during the morning hours and synchronous steep drops of mixing ratios of OCS (amplitude in the range of 60-100 ppt) and O3 (amplitude in the range of 15-30 ppb) after sunrise and before the break up of the nocturnal boundary layer. The uptake of OCS by plants was also characterized from vertical profiles. However, the time window for calculation of the ecosystem relative uptake (ERU) of OCS

  15. [A comparative study on soil fauna in native secondary evergreen broad-leaved forest and Chinese fir plantation forests in subtropics].

    Science.gov (United States)

    Yan, Shaokui; Wang, Silong; Hu, Yalin; Gao, Hong; Zhang, Xiuyong

    2004-10-01

    In this study, we investigated the response of soil animal communities to the replacement of native secondary forest by Chinese fir plantation forest and successive rotation of Chinese fir in subtropics. Three adjacent forest stands, i.e., native secondary evergreen broad-leaved forest stand (control) and Chinese fir plantation stands of first (20 yr) and second (20 yr) rotations were selected for the comparison of soil fauna. All animals were extracted from the floor litter and 0-15 cm soil layer of the stands in Summer, 2003 by using Tullgren method, wet funnel method and hand-sorting method. Compared to two Chinese fir plantation forests, the native secondary evergreen broad-leaved forest had a higher abundance and a higher taxonomic diversity of animals in soil and litter, but there were no significant differences in the biomass and productivity of soil fauna between all study stands. The abundance or diversity did not differ significantly between the first rotation and second rotation stands, too. The results supported that vegetation cover might be one of the main forces driving the development of soil animal communities, and the effect of successive rotation of Chinese fir on the development of soil fauna was a slow-running process.

  16. Tree canopy types constrain plant distributions in ponderosa pine-Gambel oak forests, northern Arizona

    Science.gov (United States)

    Scott R. Abella

    2009-01-01

    Trees in many forests affect the soils and plants below their canopies. In current high-density southwestern ponderosa pine (Pinus ponderosa) forests, managers have opportunities to enhance multiple ecosystem values by manipulating tree density, distribution, and canopy cover through tree thinning. I performed a study in northern Arizona ponderosa...

  17. 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)

  18. Some natural factors that govern the management of oaks

    Science.gov (United States)

    Sidney Weitzman; G. R., Jr. Trimble

    1957-01-01

    The oaks are the most important species group in the Appalachian hardwood forests. In West Virginia, oaks provide more than half of the lumber produced in the State. In addition, they provide a large portion of the mine timbers and specialty products.

  19. Impacts of thinning of a Mediterranean oak forest on soil properties influencing water infiltration

    NARCIS (Netherlands)

    Prima, Di Simone; Bagarello, Vincenzo; Angulo-Jaramillo, Rafael; Bautista, Inmaculada; Cerda Bolinches, Artemio; Campo, Del Antonio; González-Sanchis, María; Iovino, Massimo; Lassabatere, Laurent; Maetzke, Federico

    2017-01-01

    In Mediterranean ecosystems, special attention needs to be paid to forest-water relationships due to water scarcity. In this context, Adaptive Forest Management (AFM) has the objective to establish how forest resources have to be managed with regards to the efficient use of water, which needs

  20. 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

  1. Erosi Tanah Akibat Operasi Pemanenan Hutan (Soil Erosion Caused by Forest Harvesting Operations

    Directory of Open Access Journals (Sweden)

    Ujang Suwarna

    2011-05-01

    Full Text Available Forest harvesting operation has been known as an activity that should be considered as the main cause of soil erosion. Indonesia, the second largest owner of tropical forest, should have a serious consideration to the operation.  Therefore, the study was conducted in logged over area of a natural production forest.  The objectives of the study was to examine level of soil erosion caused by forest harvesting operations and to analyze a strategy to control level of the erosion based on its influencing factors. The study showed that forest harvesting operations caused soil erosion.  Factors that influenced the high level of the erosion were high level of precipitation, lack on planning of forest harvesting operations, no applying treatment of cross drain and cover crop in the new skidding roads, no culture of carefulness in the operations, and low human resource capacity in applying environmentally friendly forest harvesting techniques. Keywords: soil erosion, forest harvesting, logged over area, skidding road

  2. 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

  3. 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...

  4. Comparative behavior of three long-lived radionuclides in forest ecosystems

    International Nuclear Information System (INIS)

    Auerbach, S.I.

    1986-01-01

    This paper deals with studies in three forest ecosystems in eastern Tennessee, an area of rich temperate deciduous forests, sometimes referred to as mixed mesophytic forests. Two of these forest ecosystems were contaminated as a result of waste disposal operations. The third was experimentally tagged with millicurie quantities of 137 Cs. One of these ecosystems is a floodplain forest that is typical of this region. This forest has been growing on alluvial soils since 1944. Prior to that time the area was a temporary holding pond within White Oak Creek which received radioactive effluents from ORNL. Radiocesium was deposited in the pond sediments as were 90 Sr, 239 Pu, 241 Am, and other radionuclides. The dam which created the pond failed in late 1944, and the area was allowed to revert to natural conditions. The result was the development of a floodplain forest consisting of three different forest communities. The soils are fertile alluvials representative of bottomlands. The overstory tree species are principally ash, sycamore, boxelder, willow, and sweetgum (Fraxinus americana L., Plantanus occidentalis L., Acer negundo L., Salix nigra Marsh, and Liquidambar styraciflua L., respectively)

  5. A significant carbon sink in temperate forests in Beijing: based on 20-year field measurements in three stands.

    Science.gov (United States)

    Zhu, JianXiao; Hu, XueYang; Yao, Hui; Liu, GuoHua; Ji, ChenJun; Fang, JingYun

    2015-11-01

    Numerous efforts have been made to characterize forest carbon (C) cycles and stocks in various ecosystems. However, long-term observation on each component of the forest C cycle is still lacking. We measured C stocks and fluxes in three permanent temperate forest plots (birch, oak and pine forest) during 2011–2014, and calculated the changes of the components of the C cycle related to the measurements during 1992–1994 at Mt. Dongling, Beijing, China. Forest net primary production in birch, oak, and pine plots was 5.32, 4.53, and 6.73 Mg C ha-1 a-1, respectively. Corresponding net ecosystem production was 0.12, 0.43, and 3.53 Mg C ha-1 a-1. The C stocks and fluxes in 2011–2014 were significantly larger than those in 1992–1994 in which the biomass C densities in birch, oak, and pine plots increased from 50.0, 37.7, and 54.0 Mg C ha-1 in 1994 to 101.5, 77.3, and 110.9 Mg C ha-1 in 2014; soil organic C densities increased from 207.0, 239.1, and 231.7 Mg C ha-1 to 214.8, 241.7, and 238.4 Mg C ha-1; and soil heterotrophic respiration increased from 2.78, 3.49, and 1.81 Mg C ha-1 a-1 to 5.20, 4.10, and 3.20 Mg C ha-1 a-1. These results suggest that the mountainous temperate forest ecosystems in Beijing have served as a carbon sink in the last two decades. These observations of C stocks and fluxes provided field-based data for a long-term study of C cycling in temperate forest ecosystems.

  6. 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.

  7. Utilization of the invasive plant Impatiens parviflora DC. by the snail Columella edentula Draparnaud in oak-hornbeam forests

    Directory of Open Access Journals (Sweden)

    Renata Piskorz

    2011-01-01

    Full Text Available This study investigated the extend to which the snail Columella edentula is more strongly associated with the small balsam Impatiens parviflora than with other plants in the herb layer of an oak-hornbeam forest, and to interpret the character of the interaction Impatiens parviflora - Columella edentula. Numbers of C. edentula and rates of colonization were compared on various plant species under natural and laboratory conditions. Seasonal variation in snail abundance on I. parviflora was observed on permanent plots. The leaf injuries caused by C. edentula were localized in respect of the morphological and anatomical structure of leaves. The results show that I. parviflora is one of the plant species of the herb layer that are most abundantly colonized by this snail in oak-hornbeam forest. Snail finds a plant particularly suitable as a place for resting. The most favoured attachment site is on the underside of the leaf, along the midrib, which provides the highest and relatively stable humidity, as well as protection from direct sunlight and predators. I. parviflora is also a food for the snails, but they do not eat these fragments of leaves where calcium carbonate is accumulated.

  8. Sampling and Analysis Plan for White Oak Creek Watershed Remedial Investigation supplemental sampling, Oak Ridge National Laboratory, Oak Ridge, Tennessee

    International Nuclear Information System (INIS)

    1996-05-01

    This Sampling and Analysis (SAP) presents the project requirements for proposed soil sampling to support the White Oak Creek Remedial Investigation/Feasibility Study at Oak Ridge National Laboratory. During the Data Quality Objectives process for the project, it was determined that limited surface soils sampling is need to supplement the historical environmental characterization database. The primary driver for the additional sampling is the need to identify potential human health and ecological risks at various sites that have not yet proceeded through a remedial investigation. These sites include Waste Area Grouping (WAG)3, WAG 4, WAG 7, and WAG 9. WAG 4 efforts are limited to nonradiological characterization since recent seep characterization activities at the WAG have defined the radiological problem there

  9. 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...

  10. Distributional record of oak gall wasp (Hymenoptera: Cynipidae ...

    African Journals Online (AJOL)

    In this survey, oak gall wasp species were collected from the oak forests of Pardanan, Mirabad, Nalas, Sardasht, Hamran and Dar-ghabr in West-Azerbaijan province. The galls occurring on 50 cm sampled branches from four cardinal directions on each tree were counted multiple times throughout the season. Species ...

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

    Directory of Open Access Journals (Sweden)

    Antônio Ocimar Manzi

    2011-04-01

    Full Text Available 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 groundwater chemistry and soil CO2 respiration were studied in forests on sandy soils, whereas drought sensitivity of poorly-drained valley soils was investigated in an artificial drainage experiment. Slightly changes in litter decomposition or water chemistry were observed as a consequence of artificial drainage. Riparian plots did experience higher litter decomposition rates than campina forest. In response to a permanent lowering of the groundwater level from 0.1 m to 0.3 m depth in the drainage plot, topsoil carbon and nitrogen contents decreased substantially. Soil CO2 respiration decreased from 3.7±0.6 µmol m-2 s-1 before drainage to 2.5±0.2 and 0.8±0.1 µmol m-2 s-1 eight and 11 months after drainage, respectively. Soil respiration in the control plot remained constant at 3.7±0.6 µmol m-2 s-1. The above suggests that more frequent droughts may affect topsoil carbon and nitrogen content and soil respiration rates in the riparian ecosystem, and may induce a transition to less diverse campinarana or short-statured campina forest that covers areas with strongly-leached sandy soil.

  12. Litter Species Composition and Topographic Effects on Fuels and Modeled Fire Behavior in an Oak-Hickory Forest in the Eastern USA.

    Directory of Open Access Journals (Sweden)

    Matthew B Dickinson

    Full Text Available Mesophytic species (esp. Acer rubrum are increasingly replacing oaks (Quercus spp. in fire-suppressed, deciduous oak-hickory forests of the eastern US. A pivotal hypothesis is that fuel beds derived from mesophytic litter are less likely than beds derived from oak litter to carry a fire and, if they do, are more likely to burn at lower intensities. Species effects, however, are confounded by topographic gradients that affect overstory composition and fuel bed decomposition. To examine the separate and combined effects of litter species composition and topography on surface fuel beds, we conducted a common garden experiment in oak-hickory forests of the Ohio Hills. Each common garden included beds composed of mostly oak and mostly maple litter, representative of oak- and maple-dominated stands, respectively, and a mixture of the two. Beds were replenished each fall for four years. Common gardens (N = 16 were established at four topographic positions (ridges, benches on south- and northeast-facing slopes, and stream terraces at each of four sites. Litter source and topographic position had largely independent effects on fuel beds and modeled fire dynamics after four years of development. Loading (kg m-2 of the upper litter layer (L, the layer that primarily supports flaming spread, was least in more mesic landscape positions and for maple beds, implying greater decomposition rates for those situations. Bulk density in the L layer (kg m-3 was least for oak beds which, along with higher loading, would promote fire spread and fireline intensity. Loading and bulk density of the combined fermentation and humic (FH layers were least on stream terrace positions but were not related to species. Litter- and FH-layer moistures during a 5-day dry-down period after a rain event were affected by time and topographic effects while litter source effects were not evident. Characteristics of flaming combustion determined with a cone calorimeter pointed to greater

  13. The weight of the past: land-use legacies and recolonization of pine plantations by oak trees.

    Science.gov (United States)

    Navarro-González, Irene; Pérez-Luque, Antonio J; Bonet, Francisco J; Zamora, Regino

    2013-09-01

    Most of the world's plantations were established on previously disturbed sites with an intensive land-use history. Our general hypothesis was that native forest regeneration within forest plantations depends largely on in situ biological legacies as a source of propagules. To test this hypothesis, we analyzed native oak regeneration in 168 pine plantation plots in southern Spain in relation to land use in 1956, oak patch proximity, and pine tree density. Historical land-use patterns were determined from aerial photography from 1956, and these were compared with inventory data from 2004-2005 and additional orthophoto images. Our results indicate that oak forest regeneration in pine plantations depends largely on land-use legacies, although nearby, well-conserved areas can provide propagules for colonization from outside the plantation, and pine tree density also affected oak recruit density. More intense land uses in the past meant fewer biological legacies and, therefore, lower likelihood of regenerating native forest. That is, oak recruit density was lower when land use in 1956 was croplands (0.004 +/- 0.002 recruits/m2 [mean +/- SE]) or pasture (0.081 +/- 0.054 recruits/m2) instead of shrubland (0.098 +/- 0.031 recruits/m2) or oak formations (0.314 +/- 0.080 recruits/m2). Our study shows that land use in the past was more important than propagule source distance or pine tree density in explaining levels of native forest regeneration in plantations. Thus, strategies for restoring native oak forests in pine plantations may benefit from considering land-use legacies as well as distance to propagule sources and pine density.

  14. 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.

  15. 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.

  16. 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

  17. Micro-Food Web Structure Shapes Rhizosphere Microbial Communities and Growth in Oak

    Directory of Open Access Journals (Sweden)

    Hazel R. Maboreke

    2018-03-01

    Full Text Available The multitrophic interactions in the rhizosphere impose significant impacts on microbial community structure and function, affecting nutrient mineralisation and consequently plant performance. However, particularly for long-lived plants such as forest trees, the mechanisms by which trophic structure of the micro-food web governs rhizosphere microorganisms are still poorly understood. This study addresses the role of nematodes, as a major component of the soil micro-food web, in influencing the microbial abundance and community structure as well as tree growth. In a greenhouse experiment with Pedunculate Oak seedlings were grown in soil, where the nematode trophic structure was manipulated by altering the proportion of functional groups (i.e., bacterial, fungal, and plant feeders in a full factorial design. The influence on the rhizosphere microbial community, the ectomycorrhizal symbiont Piloderma croceum, and oak growth, was assessed. Soil phospholipid fatty acids were employed to determine changes in the microbial communities. Increased density of singular nematode functional groups showed minor impact by increasing the biomass of single microbial groups (e.g., plant feeders that of Gram-negative bacteria, except fungal feeders, which resulted in a decline of all microorganisms in the soil. In contrast, inoculation of two or three nematode groups promoted microbial biomass and altered the community structure in favour of bacteria, thereby counteracting negative impact of single groups. These findings highlight that the collective action of trophic groups in the soil micro-food web can result in microbial community changes promoting the fitness of the tree, thereby alleviating the negative effects of individual functional groups.

  18. Transfer of radio-cesium from forest soil to woodchips using fungal activities

    Science.gov (United States)

    Kaneko, Nobuhiro; Huang, Yao; Tanaka, Yoichiro; Fujiwara, Yoshihiro; Sasaki, Michiko; Toda, Hiroto; Takahashi, Terumasa; Kobayashi, Tatsuaki; Harada, Naoki; Nonaka, Masahiro

    2014-05-01

    Raido-cesium released to terrestrial ecosystems by nuclear accidents is know to accumulate forest soil and organic layer on the soil. Forests in Japan are not exceptions. Practically it is impossible to decontaminate large area of forests. However, there is a strong demand from local people, who has been using secondary forests (Satoyama) around croplands in hilly areas, to decontaminate radio-cesium, because those people used to collect wild mushrooms and edible plants, and there are active cultures of mushrooms using logs and sawdusts. These natural resource uses consist substantial part of their economical activities, Therefore it is needed to decontaminate some selected part of forests in Japan to local economy. Clear cutting and scraping surface soil and organic matter are common methods of decontamination. However the efficiency of decontamination is up to 30% reduction of aerial radiation, and the cost to preserve contaminated debris is not affordable. In this study we used wood chips as a growth media for saprotrophic fungi which are known to accumulate redio-cesium. There are many studies indicated that mushrooms accumulated redio-cesium from forest soil and organic layer. It is not practical to collect mushrooms to decontaminate redio-cesium, because biomass of mushrooms are not enough to collect total contaminants. Mushrooms are only minor part of saprotrophic fungi. Fungal biomass in forest soil is about 1% of dead organic matter on forest floor. Our previous study to observe Cs accumulation to decomposing leaf litter indicated 18% absorption of total soil radio-Cs to litter during one year field incubation (Kaneko et al., 2013), and Cs concentration was proportional to fungal biomass on litter. This result indicated that fungi transferred radio-cesium around newly supplied leaf litter free of contamination. Therefore effective decontamination will be possible if we can provide large amount of growth media for saprotrophic fungi, and the media can be

  19. Growth and mycorrhizal community structure of Pinus sylvestris seedlings following the addition of forest litter.

    Science.gov (United States)

    Aucina, Algis; Rudawska, Maria; Leski, Tomasz; Skridaila, Audrius; Riepsas, Edvardas; Iwanski, Michal

    2007-08-01

    We report the effects of pine and oak litter on species composition and diversity of mycorrhizal fungi colonizing 2-year-old Pinus sylvestris L. seedlings grown in a bare-root nursery in Lithuania. A layer of pine or oak litter was placed on the surface of the nursery bed soil to mimic natural litter cover. Oak litter amendment appeared to be most favorable for seedling survival, with a 73% survival rate, in contrast to the untreated mineral bed soil (44%). The concentrations of total N, P, K, Ca, and Mg were higher in oak growth medium than in pine growth medium. Relative to the control (pH 6.1), the pH was lower in pine growth medium (5.8) and higher in oak growth medium (6.3). There were also twofold and threefold increases in the C content of growth medium with the addition of pine and oak litter, respectively. Among seven mycorrhizal morphotypes, eight different mycorrhizal taxa were identified: Suillus luteus, Suillus variegatus, Wilcoxina mikolae, a Tuber sp., a Tomentella sp., Cenococcum geophilum, Amphinema byssoides, and one unidentified ectomycorrhizal symbiont. Forest litter addition affected the relative abundance of mycorrhizal symbionts more than their overall representation. This was more pronounced for pine litter than for oak litter, with 40% and 25% increases in the abundance of suilloid mycorrhizae, respectively. Our findings provide preliminary evidence that changes in the supply of organic matter through litter manipulation may have far-reaching effects on the chemistry of soil, thus influencing the growth and survival of Scots pine seedlings and their mycorrhizal communities.

  20. Growth and Mycorrhizal Community Structure of Pinus sylvestris Seedlings following the Addition of Forest Litter▿

    Science.gov (United States)

    Aučina, Algis; Rudawska, Maria; Leski, Tomasz; Skridaila, Audrius; Riepšas, Edvardas; Iwanski, Michal

    2007-01-01

    We report the effects of pine and oak litter on species composition and diversity of mycorrhizal fungi colonizing 2-year-old Pinus sylvestris L. seedlings grown in a bare-root nursery in Lithuania. A layer of pine or oak litter was placed on the surface of the nursery bed soil to mimic natural litter cover. Oak litter amendment appeared to be most favorable for seedling survival, with a 73% survival rate, in contrast to the untreated mineral bed soil (44%). The concentrations of total N, P, K, Ca, and Mg were higher in oak growth medium than in pine growth medium. Relative to the control (pH 6.1), the pH was lower in pine growth medium (5.8) and higher in oak growth medium (6.3). There were also twofold and threefold increases in the C content of growth medium with the addition of pine and oak litter, respectively. Among seven mycorrhizal morphotypes, eight different mycorrhizal taxa were identified: Suillus luteus, Suillus variegatus, Wilcoxina mikolae, a Tuber sp., a Tomentella sp., Cenococcum geophilum, Amphinema byssoides, and one unidentified ectomycorrhizal symbiont. Forest litter addition affected the relative abundance of mycorrhizal symbionts more than their overall representation. This was more pronounced for pine litter than for oak litter, with 40% and 25% increases in the abundance of suilloid mycorrhizae, respectively. Our findings provide preliminary evidence that changes in the supply of organic matter through litter manipulation may have far-reaching effects on the chemistry of soil, thus influencing the growth and survival of Scots pine seedlings and their mycorrhizal communities. PMID:17575001

  1. Vegetation series, curve numbers and soil water availabilities. Application to forest restoration in dry lands; Series de vegetacion, numeros de curva y disponibilidades hidricas. Aplicacion a la restauracion forestal en zonas secas

    Energy Technology Data Exchange (ETDEWEB)

    Mongil, J.; Martin, L.; Navarro, J.; Martinez de Azagra, A.

    2012-11-01

    Vegetation series related with plants succession in the ecosystems are associated to hydrologic properties of the land such as runoff curve numbers, runoff thresholds and soil water availability. The most evolved vegetation stages in a successional series usually present better soil and hydrologic conditions. In this way curve numbers decrease meanwhile runoff thresholds increase, and therefore water availability grows in the ecosystem. These postulates are analyzed in this paper using field data (7 sampling points) and a hydrologic model (MODIPE). One vegetation series (specifically: Guadarramico-Iberica (supra-meso) holm oak siliceous series) and its successional stages have been chosen to find out its associated curve numbers and ecosystem water availability using MODIPE model. The objective is to apply these items to hydrologic planning and forest restoration in dry lands, where water floods and water scarcity control urban and ecosystem development and restoration measures. (Author) 37 refs.

  2. Does Forest Continuity Enhance the Resilience of Trees to Environmental Change?

    Directory of Open Access Journals (Sweden)

    Goddert von Oheimb

    Full Text Available There is ample evidence that continuously existing forests and afforestations on previously agricultural land differ with regard to ecosystem functions and services such as carbon sequestration, nutrient cycling and biodiversity. However, no studies have so far been conducted on possible long-term (>100 years impacts on tree growth caused by differences in the ecological continuity of forest stands. In the present study we analysed the variation in tree-ring width of sessile oak (Quercus petraea (Matt. Liebl. trees (mean age 115-136 years due to different land-use histories (continuously existing forests, afforestations both on arable land and on heathland. We also analysed the relation of growth patterns to soil nutrient stores and to climatic parameters (temperature, precipitation. Tree rings formed between 1896 and 2005 were widest in trees afforested on arable land. This can be attributed to higher nitrogen and phosphorous availability and indicates that former fertilisation may continue to affect the nutritional status of forest soils for more than one century after those activities have ceased. Moreover, these trees responded more strongly to environmental changes - as shown by a higher mean sensitivity of the tree-ring widths - than trees of continuously existing forests. However, the impact of climatic parameters on the variability in tree-ring width was generally small, but trees on former arable land showed the highest susceptibility to annually changing climatic conditions. We assume that incompletely developed humus horizons as well as differences in the edaphon are responsible for the more sensitive response of oak trees of recent forests (former arable land and former heathland to variation in environmental conditions. We conclude that forests characterised by a long ecological continuity may be better adapted to global change than recent forest ecosystems.

  3. 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.

  4. Short-term response of small mammals following oak regeneration silviculture treatments.

    Science.gov (United States)

    Amy L. Raybuck; Christopher E. Moorman; Christopher S. DePerno; Kevin Gross; Dean M. Simon; Gordon S. Warburton

    2012-01-01

    Upland, mixed-oak forests in the eastern United States have experienced widespread oak regeneration failure, largely due to cessation of anthropogenic disturbance. Silvicultural practices used to promote advance oak regeneration may affect ground-dwelling mammals. From May to August 2008 (pre-treatment), 2010 (first year post-treatment), and 2011 (second year post-...

  5. 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

  6. 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.

  7. Epiphytic lichen diversity in central European oak forests: Assessment of the effects of natural environmental factors and human influences

    International Nuclear Information System (INIS)

    Svoboda, David; Peksa, Ondrej; Vesela, Jana

    2010-01-01

    We investigated lichen diversity in temperate oak forests using standardized protocols. Forty-eight sites were sampled in the Czech Republic, Slovakia and Hungary. The effects of natural environmental predictors and human influences on lichen diversity (lichen diversity value, species richness) were analysed by means of correlation tests. We found that lichen diversity responded differently to environmental predictors between two regions with different human impact. In the industrial region, air pollution was the strongest factor. In the agricultural to highly forested regions, lichen diversity was strongly influenced by forest age and forest fragmentation. We found that several natural factors can in some cases obscure the effect of human influences. Thus, factors of naturality gradient must be considered (both statistically and interpretively) when studying human impact on lichen diversity. - We detected the different responses of lichens to ecological predictors in polluted and unpolluted areas.

  8. The tree-species-specific effect of forest bathing on perceived anxiety alleviation of young-adults in urban forests

    Directory of Open Access Journals (Sweden)

    Haoming Guan

    2017-12-01

    Full Text Available Forest bathing, i.e. spending time in a forest to walk, view and breathe in a forest, can alleviate the mental depression of visitors, but the tree-species-specific effect of this function by the urban forest is unknown. In this study, sixty-nine university students (aged 19-22, male ratio: 38% were recruited as participants to visit urban forests dominated by birch (Betula platyphylla Suk., maple (Acer triflorum Komarov and oak (Quercus mongolica Fisch. ex Ledeb trees in a park at the center of Changchun City, Northeast China. In the maple forest only the anxiety from study interest was decreased, while the anxiety from employment pressure was alleviated to the most extent in the birch forest. Participants perceived more anxiety from lesson declined in the oak forest than in the birch forest. Body parameters of weight and age were correlated with the anti-anxiety scores. In the oak forest, female participants can perceive more anxiety alleviation than male participants. For university students, forest bathing in our study can promote their study interest. Forest bathing can be more effective to alleviate the anxiety of young adults with greater weight. The birch forest was recommended to be visited by students to alleviate the pressure of employment worry, and the oak forest was recommended to be visited by girls.

  9. 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

  10. Magnetic Soils Profiles in the Volga-Kama Forest-Steppe Region

    Directory of Open Access Journals (Sweden)

    L.A. Fattakhova

    2016-09-01

    Full Text Available The magnetic properties of virgin forest-steppe soils developed on the originally vertically uniform unconsolidated parent material have been investigated. The profile samples of virgin dark-grey forest light-clayey soil derived from a siltstone of the Kazan layer of the Upper Permian and virgin leached medium-thick fertile light-clayey chernozem derived from a Quaternary heavy deluvial loam have been considered. Both soils are characterized by the accumulative type of magnetic susceptibility and F-factor values distribution patterns with depth. In the humus part of the soil profile, magnetics are present pre-dominantly in the < 2.5 µm fraction. The coercivity spectra allowed to determine the contribution of dia-/paramagnetic and ferromagnetic components to magnetic susceptibility. It has been found that magnetic susceptibility enhancement in the organogenic horizons of virgin forest-steppe soils occurs due to the contribution of ferromagnetic components. The results indicate a strong positive linear correlation between the magnetic susceptibility and oxalate-extractable Fe, as well as between the magnetic susceptibility and Schwertmann’s criterion values. Using the method of thermomagnetic analysis of the < 2.5 µm fraction, it has been found that the magnetic susceptibility enhancement in the profiles of forest-steppe soils took place due to the formation of maghemite-magnetite associations. The predominantly ferromagnetic fraction consists of small single-domain grains.

  11. 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.

  12. 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.

  13. Status and conservation of old-growth forests and endemic birds in the pine-oak zone of the Sierra Madre Occidental, Mexico

    NARCIS (Netherlands)

    Lammertink, J.M.; Rojas-Tomé, J.A.; Casillas-Orona, F.M.; Otto, R.L.

    1996-01-01

    The pine-oak forests of the Sierra Madre Occidental, a mountain range in NW Mexico, have recently been recognized as an area of high endemism and biodiversity. Selective logging threatens three bird species endemic to this habitat, who depend on standing dead trees (snags). This report is based on

  14. Ability of LANDSAT-8 Oli Derived Texture Metrics in Estimating Aboveground Carbon Stocks of Coppice Oak Forests

    Science.gov (United States)

    Safari, A.; Sohrabi, H.

    2016-06-01

    The role of forests as a reservoir for carbon has prompted the need for timely and reliable estimation of aboveground carbon stocks. Since measurement of aboveground carbon stocks of forests is a destructive, costly and time-consuming activity, aerial and satellite remote sensing techniques have gained many attentions in this field. Despite the fact that using aerial data for predicting aboveground carbon stocks has been proved as a highly accurate method, there are challenges related to high acquisition costs, small area coverage, and limited availability of these data. These challenges are more critical for non-commercial forests located in low-income countries. Landsat program provides repetitive acquisition of high-resolution multispectral data, which are freely available. The aim of this study was to assess the potential of multispectral Landsat 8 Operational Land Imager (OLI) derived texture metrics in quantifying aboveground carbon stocks of coppice Oak forests in Zagros Mountains, Iran. We used four different window sizes (3×3, 5×5, 7×7, and 9×9), and four different offsets ([0,1], [1,1], [1,0], and [1,-1]) to derive nine texture metrics (angular second moment, contrast, correlation, dissimilar, entropy, homogeneity, inverse difference, mean, and variance) from four bands (blue, green, red, and infrared). Totally, 124 sample plots in two different forests were measured and carbon was calculated using species-specific allometric models. Stepwise regression analysis was applied to estimate biomass from derived metrics. Results showed that, in general, larger size of window for deriving texture metrics resulted models with better fitting parameters. In addition, the correlation of the spectral bands for deriving texture metrics in regression models was ranked as b4>b3>b2>b5. The best offset was [1,-1]. Amongst the different metrics, mean and entropy were entered in most of the regression models. Overall, different models based on derived texture metrics

  15. Light and soil humidity influencing oak seedling growth and physiology in mixed hardwood gaps

    Directory of Open Access Journals (Sweden)

    Raddi S

    2009-06-01

    Full Text Available In “S. Rossore, Migliarino, Massaciuccoli” Natural Park (Pisa, I six-month-old pedunculate oak seedlings (Quercus robur L. were transplanted within natural gaps of a mixed oak forest. Micro-environmental variability for radiation and water soil content were measured for 145 seedlings during the year. Irradiation relative to the open field (IR ranged from 5% to 57%. Seven classes of IR each with 20 seedlings were selected. Leaf mass per area was strongly influenced by IR. In the first 3 years survival was high (95, 76 and 75%, respectively and seedling reached 14±6 cm, 27±13 cm and 39±19 (sd cm of height. Even if IR and soil water content (SWC were negatively associated, indicating a lower SWC at the centre of the gaps, height and its relative growth rate increased with IR (explored range: 8-40% with a significant interaction with SWC in the 1st year, indicating the positive effect of soil moisture. In the 3rd year dimensional traits were higher in L+W+ (high light and humidity followed by L-W+ (low light and high humidity, L+W- and finally by L-W-. Summer drought typical of the Mediterranean climate was evaluated by chlorophyll fluorescence of PSII on apical leaves of seedlings and mature trees at the beginning (21 June and in mid-summer (20 July. While in June physiological traits did not differ between low and high IR, in mid-summer (at the peak of water-stress seedlings of the two highest light classes showed chronic photoinhibition (Fv/Fm<0.75 and an increase in thermal dissipation (D by constitutive term (Dc=1-Fv/Fm and by regulated mechanisms of dissipation through xanthophyll-cycle term (Dx. Moreover, in July seedling leaf physiology largely differed with IR: leaves acclimated to high IR have higher photosynthetic potentialities, as shown by electron transport rate (ETR and quantum yield (P at saturating light maintained by an increase of the fraction of open reaction centres (qP, counterbalancing the efficiency decrease of the

  16. 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.

  17. 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),...

  18. Alterations to throughfall water and solute flux by Tillandsias usneoides L. (Spanish moss) cover in a maritime live oak forest

    Science.gov (United States)

    Gay, T. E.; Van Stan, J. T., II; Reichard, J. S.; Moore, L. D.; Lewis, E. S.

    2014-12-01

    Alterations to forest canopy structures can have a direct effect on hydrological and biogeochemical cycles in forest ecosystems. Epiphytes act as additional canopy biomass intercepting water, effecting pathways under different micrometeorological conditions and alternating nutrient uptake/releases. Most studies on epiphyte cover have focused on non-vascular epiphytes (e.g., lichen and bryophyte mosses), leaving vascular epiphytes like Tillandsia usneoides L. (Spanish moss) relatively understudied. To fill this gap, we characterized alterations to throughfall water and dissolved ion enrichment/flux to soils by T. usneoides in a Quercus Virginiana Mill. (southern live oak) stand on St. Catherine's Island. Specifically, we compare throughfall generated from heavy T. usneoides coverage, bare canopy, and a continuum of T. usneoides cover percentages (~400 water & 210 chemistry observations over ~40 storms for each canopy cover category). Findings show T.usneoides acts as a significant water storage agent, significantly reducing throughfall. However, under certain meteorological conditions T. usneoides can become saturated and act as a funneling "hotspot." Tillandsia usneoides coverage enriched throughfall with primarily dry deposited ions (Na+,Cl-, SO42-, Li+), leached greater Mg2+, Ca2+, reduced NO3- and increased NH4+ concentrations. Dry deposited ion enrichment is likely a result of the moss' greater surface roughness. It has been shown that epiphytes prefer to leach Mg2+ and Ca2+. Increased NH4+ suggests that the saturated T. usneoides mat likely hosts microbial decomposition of leaf, branch, and bark biomass ensnared in the plant itself. K-means cluster analysis on the storms revealed 4 storm types of the differing meteorological conditions (windy/calm, dry/wet [high/low VPD], high/low intensity, intermittent/consistent), and these throughfall dynamics varied between these storm types. Discussion of future research questions regarding how these throughfall

  19. 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.)

  20. Dynamics of forest populations in the mountain resort region of the North Caucasus

    Science.gov (United States)

    Chalaya, Elena; Efimenko, Natalia; Slepykh, Olga; Slepykh, Viktor; Povolotskaya, Nina

    2017-04-01

    field maple. Succession of the oak replacement in natural stand of the vegetative origin can be explained with the soil fatigue under the oak forest inhibiting its own regrowth [2]. However, you can observe the same succession of the oak replacement by other native species in the artificial planting of the oak on the virgin meadow lands. Therefore, the exogenous factors proceeding against the background of global warming during the number of decades are the reason of the succession. The nature of this process demands further studying. References 1.Kazankin A.P. Ecological role of the mountain woods of the Caucasus. Novosibirsk: Siberian Branch of the Russian Academy of Science publishing house, 2013. - 366 p. 2. Slepykh, V.V. Successions and bioclimate of oak groves in the resort region Caucasian MineralnyeVody / V.V.Slepykh, N.P.Povolotskaya// Resort medicine, № 3, 2015. - P. 18-27.

  1. Effects of a low severity prescribed fire on water-soluble elements in ash from a cork oak (Quercus suber) forest located in the northeast of the Iberian Peninsula

    Science.gov (United States)

    Pereira, P.; beda, X.; Martin, D.; Mataix-Solera, J.; Guerrero, C.

    2011-01-01

    Wildfire is the major disturbance in Mediterranean forests. Prescribed fire can be an alternative to reduce the amount of fuel and hence decrease the wildfire risk. However the effects of prescribed fire must be studied, especially on ash properties, because ash is an important nutrient source for ecosystem recovery. The aim of this study is to determine the effects of a low severity prescribed fire on water-soluble elements in ash including pH, electrical conductivity (EC), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), aluminum (Al), manganese (Mn), iron (Fe), zinc (Zn), silica (SiO2) and total sulphur (TS). A prescribed fire was conducted in a cork oak (Quercus suber) (Q.S) forest located in the northeast part of the Iberian Peninsula. Samples were collected from a flat plot of 40??70m mainly composed of Q.S and Quercus robur (Q.R) trees. In order to understand the effects of the prescribed fire on the soluble elements in ash, we conducted our data analysis on three data groups: all samples, only Q.S samples and only Q.R samples. All three sample groups exhibited a significant increase in pH, EC (p<0.001), water-soluble Ca, Mg, Na, SiO2 and TS and a decrease in water-soluble Mn, Fe and Zn. Differences were identified between oak species for water-soluble K, Al and Fe. In Q.S samples we registered a significant increase in the first two elements p<0.001 and p<0.01, respectively, and a non-significant impact in the third, at p<0.05. In Q.R data we identified a non-significant impact on water-soluble K and Al and a significant decrease in water-soluble Fe (p<0.05). These differences are probably due to vegetation characteristics and burn severity. The fire induced a higher variability in the ash soluble elements, especially in Q.S samples, that at some points burned with higher severity. The increase of pH, EC, Ca, Mg, Na and K will improve soil fertility, mainly in the study area where soils are acidic. The application of this low severity prescribed

  2. 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

  3. Divergent Responses of Forest Soil Microbial Communities under Elevated CO2 in Different Depths of Upper Soil Layers.

    Science.gov (United States)

    Yu, Hao; He, Zhili; Wang, Aijie; Xie, Jianping; Wu, Liyou; Van Nostrand, Joy D; Jin, Decai; Shao, Zhimin; Schadt, Christopher W; Zhou, Jizhong; Deng, Ye

    2018-01-01

    Numerous studies have shown that the continuous increase of atmosphere CO 2 concentrations may have profound effects on the forest ecosystem and its functions. However, little is known about the response of belowground soil microbial communities under elevated atmospheric CO 2 (eCO 2 ) at different soil depth profiles in forest ecosystems. Here, we examined soil microbial communities at two soil depths (0 to 5 cm and 5 to 15 cm) after a 10-year eCO 2 exposure using a high-throughput functional gene microarray (GeoChip). The results showed that eCO 2 significantly shifted the compositions, including phylogenetic and functional gene structures, of soil microbial communities at both soil depths. Key functional genes, including those involved in carbon degradation and fixation, methane metabolism, denitrification, ammonification, and nitrogen fixation, were stimulated under eCO 2 at both soil depths, although the stimulation effect of eCO 2 on these functional markers was greater at the soil depth of 0 to 5 cm than of 5 to 15 cm. Moreover, a canonical correspondence analysis suggested that NO 3 -N, total nitrogen (TN), total carbon (TC), and leaf litter were significantly correlated with the composition of the whole microbial community. This study revealed a positive feedback of eCO 2 in forest soil microbial communities, which may provide new insight for a further understanding of forest ecosystem responses to global CO 2 increases. IMPORTANCE The concentration of atmospheric carbon dioxide (CO 2 ) has continuously been increasing since the industrial revolution. Understanding the response of soil microbial communities to elevated atmospheric CO 2 (eCO 2 ) is important for predicting the contribution of the forest ecosystem to global atmospheric change. This study analyzed the effect of eCO 2 on microbial communities at two soil depths (0 to 5 cm and 5 to 15 cm) in a forest ecosystem. Our findings suggest that the compositional and functional structures of microbial

  4. 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

  5. Fire and the production of Astraeus odoratus (Basidiomycetes sporocarps in deciduous dipterocarp-oak forests of northern Thailand

    Directory of Open Access Journals (Sweden)

    Keegan H. Kennedy

    2012-12-01

    Full Text Available The genus Astraeus (Diplocystidiaceae forms ectomycorrhizal associations with many tree species and is a common gasteromycete in tropical and temperate ecosystems worldwide. In Thailand, Astraeus is most prevalent in deciduous dipterocarp-oak forest (DOF in the north and north-east and its ecology is uniquely associated with fire. Rural villagers often burn the seasonally dry DOF ground vegetation causing significant environmental disturbance to promote the growth of Astraeus sporocraps—a local culinary delicacy and important source of household income. The purpose of this work is to investigate whether the practice of burning DOF stimulates the production of Astraeus sporocarps in DOF. Burned and unburned Astraeus habitat was surveyed over two years at two sites in Chiang Mai province and one site in Mae Hong Son province. Changes in soil fungi after a fire as well as vascular vegetation growing with Astraeus were studied. All sporocarps collected were identified as Astraeus odoratus. Astraeus sporocarps were found in both burned and unburned areas in 2010. In 2011, an unusually wet year, no sporocarps were found in burned or unburned areas. The top 2 cm of soil experienced high temperatures which killed fungi, but lower depths were well insulated from the heat. A wide range of vascular flora grew in Astraeus habitat, the most common tree species being Dipterocarpus tuberculatus var. tuberculatus and Dipterocarpus obtusifolius var. obtusifolius. This study shows that Astraeus can produce sporocarps without fire and future work can focus on more environmentally benign methods of harvesting this popular mushroom.

  6. 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.

  7. 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.

  8. 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

  9. Effects of a low severity prescribed fire on water-soluble elements in ash from a cork oak (Quercus suber) forest located in the northeast of the Iberian Peninsula.

    Science.gov (United States)

    Pereira, Paulo; Ubeda, Xavier; Martin, Deborah; Mataix-Solera, Jorge; Guerrero, César

    2011-02-01

    Wildfire is the major disturbance in Mediterranean forests. Prescribed fire can be an alternative to reduce the amount of fuel and hence decrease the wildfire risk. However the effects of prescribed fire must be studied, especially on ash properties, because ash is an important nutrient source for ecosystem recovery. The aim of this study is to determine the effects of a low severity prescribed fire on water-soluble elements in ash including pH, electrical conductivity (EC), calcium (Ca), magnesium (Mg), sodium (Na), potassium (K), aluminum (Al), manganese (Mn), iron (Fe), zinc (Zn), silica (SiO(2)) and total sulphur (TS). A prescribed fire was conducted in a cork oak (Quercus suber) (Q.S) forest located in the northeast part of the Iberian Peninsula. Samples were collected from a flat plot of 40×70m mainly composed of Q.S and Quercus robur (Q.R) trees. In order to understand the effects of the prescribed fire on the soluble elements in ash, we conducted our data analysis on three data groups: all samples, only Q.S samples and only Q.R samples. All three sample groups exhibited a significant increase in pH, EC (pfire induced a higher variability in the ash soluble elements, especially in Q.S samples, that at some points burned with higher severity. The increase of pH, EC, Ca, Mg, Na and K will improve soil fertility, mainly in the study area where soils are acidic. The application of this low severity prescribed fire will improve soil nutrient status without causing soil degradation and thus is considered to be a good management strategy. Copyright © 2010 Elsevier Inc. All rights reserved.

  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. 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

  12. Regime shifts and weakened environmental gradients in open oak and pine ecosystems.

    Directory of Open Access Journals (Sweden)

    Brice B Hanberry

    Full Text Available Fire suppression allows tree species that are intolerant of fire stress to increase their distribution, potentially resulting in disruption of historical species-environmental relationships. To measure changes between historical General Land Office surveys (1815 to 1850 and current USDA Forest Inventory and Assessment surveys (2004 to 2008, we compared composition, distribution, and site factors of 21 tree species or species groups in the Missouri Ozarks. We used 24 environmental variables and random forests as a classification method to model distributions. Eastern redcedar, elms, maples, and other fire-sensitive species have increased in dominance in oak forests, with concurrent reductions by oak species; specific changes varied by ecological subsection. Ordinations displayed loss of separation between formerly distinctive oak and fire-sensitive tree species groups. Distribution maps showed decreased presence of disturbance-dependent oak and pine species and increased presence of fire-sensitive species that generally expanded from subsections protected from fire along rivers to upland areas, except for eastern redcedar, which expanded into these subsections. Large scale differences in spatial gradients between past and present communities paralleled reduced influence of local topographic gradients in the varied relief of the Missouri Ozarks, as fire-sensitive species have moved to higher, drier, and sunnier sites away from riverine corridors. Due to changes in land use, landscapes in the Missouri Ozarks, eastern United States, and world-wide are changing from open oak and pine-dominated ecosystems to novel oak-mixed species forests, although at fine scales, forests are becoming more diverse in tree species today. Fire suppression weakened the influence by environmental gradients over species dominance, allowing succession from disturbance-dependent oaks to an alternative state of fire-sensitive species. Current and future research and

  13. 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.)

  14. 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...

  15. Properties of Hungarian oak(quercus conferta Kit. wood from the Hilandar Monastery forest

    Directory of Open Access Journals (Sweden)

    Popović Zdravko

    2007-01-01

    Full Text Available This paper presents the study results of the basic physical and strength properties of Hungarian oak (Quercus conferta Kit. wood from the Kakovo Monastery forests of Hilandar Monastery in Greece. Wood properties were analyzed in detail, as an indispensable proof of wood quality and its use for joinery, interiors and wooden floors. The basic physical properties of wood (moisture content at the time of tree felling, density and volume porosity and the basic strength properties (compressive strength, bending strength and module of elasticity were researched. The results are presented in Tables and in Diagrams with statistical parameters and compared to the literature data. The correlation of the study properties of wood was also analyzed.

  16. Status and conservation of old-growth forests and endemic birds in the pine-oak zone of the Sierra Madre occidental Mexico

    OpenAIRE

    Lammertink, J.M.; Rojas-Tome, J.A.; Casillas-Orona, F.M.; Otto, R.L.

    1996-01-01

    The pine-oak forests of the Sierra Madre Occidental, a mountain range in NW Mexico, have recently been recognized as an area of high endemism and biodiversity. Selective logging threatens three bird species endemic to this habitat, who depend on standing dead trees (snags). This report is based on an 11 month field survey that aimed to locate oldgrowth remnants and to assess the status of the endemic birds. Old-growth is defined here as a forest that has never been logged mechanically. Old-gr...

  17. 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

  18. Floristic diversity of posavina's floodplain forests in serbia and their wider geographical context

    International Nuclear Information System (INIS)

    Jurisic, B.; Puvaca, N.

    2014-01-01

    In order to detect floristic divergence of analysed stands we applied TWINSPAN classification and ordinary Correspondence Analysis. Both analyses have shown an almost identical result of floristic composition, where 114 studied samples were grouped into seven association groups at the third twinspan classification level. These seven groups, successively from the most humid to most dry, comprising two large groups of plant associations, completely corresponding to two alliances: Forest of Pedunculate Oak and Alder and Forest of Pedunculate Oak and Hornbeam. SIMPER procedure have shown tahat within the first 20.51% of cumulative contribution, the floristic divegence among the studied forest stands includes 13 taxa: Carpinus betulus., Fraxinus angustifolia, Quercus cerris, Amorpha fruticosa, Convallaria majalis, Crataegus oxyacantha, Quercus robur, Lysimachia nummularia, Tamus communis, Galium aparine, Rubus caesius, Ulmus carpinifolia and Ajuga reptans. ANOSIM analysis were used to determine the degree of floristic discontinuity. It was largest between forest of Pedunculate Oak, Hornbeam and Turkey Oak and forest of Pedunculate Oak and Ash (statistics R = 0.8824 (p<0.001)). The lowest floristic dissimilarity was between the forest of Pedunculate Oak, Hornbeam and Turkey Oak and forest of Pedunculate Oak, Hornbeam and Turkey Oak with Lindens, where R = 0.2009 (p<0.01). Posavina floodplain forests in Serbia generally show good agreement with analogous communities in neighbouring countries in the Balkan peninsula and Central Europe. (author)

  19. 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.

  20. Stand restoration burning in oak-pine forests in the southern Applachians: effects on aboveground biomass and carbon and nitrogen cycling

    Science.gov (United States)

    Robert M. Hubbard; James M. Vose; Barton D. Clinton; Katherine J. Elliott; Jennifer D. Knoepp

    2004-01-01

    Understory prescribed burning is being suggested as a viable management tool for restoring degraded oak–pine forest communities in the southern Appalachians yet information is lacking on how this will affect ecosystem processes. Our objectives in this study were to evaluate the watershed scale effects of understory burning on total aboveground biomass, and the carbon...

  1. Sudden oak death: disease trends in Marin county plots after one year

    Science.gov (United States)

    Brice A. McPherson; David L. Wood; Andrew J. Storer; Nina Maggi Kelly; Richard B. Standiford

    2002-01-01

    Sudden oak death has emerged as a major threat to the oak forests of California. In oaks and tanoak, this disease complex consists of a previously unreported fungus-like pathogen, Phytophthora ramorum, insects (bark and ambrosia beetles), and a secondary fungus, Hypoxylon thouarsianum. Species monitored in this study were coast...

  2. Spatio-Temporal Trends of Oak Decline and Mortality under Periodic Regional Drought in the Ozark Highlands of Arkansas and Missouri

    Science.gov (United States)

    Zhaofei Fan; Xiuli Fan; Michael K. Crosby; W. Keith Moser; Hong He; Martin A. Spetich; Stephen R. Shifley

    2012-01-01

    At the forest landscape/region level, based on annual Forest Inventory and Analysis plot data from 1999 to 2010, oak decline and mortality trends for major oak species (groups) were examined in the Ozark Highlands of Arkansas and Missouri. Oak decline has elevated cumulative mortality of red oak species to between 11 and 15 percent in terms of relative density and...

  3. 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

  4. 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.

  5. Contribution of Soil Fauna to Foliar Litter-Mass Loss in Winter in an Ecotone between Dry Valley and Montane Forest in the Upper Reaches of the Minjiang River.

    Science.gov (United States)

    Peng, Yan; Yang, Wanqin; Li, Jun; Wang, Bin; Zhang, Chuan; Yue, Kai; Wu, Fuzhong

    2015-01-01

    Litter decomposition during winter can provide essential nutrients for plant growth in the subsequent growing season, which plays important role in preventing the expansion of dry areas and maintaining the stability of ecotone ecosystems. However, limited information is currently available on the contributions of soil fauna to litter decomposition during winter in such ecosystems. Therefore, a field experiment that included litterbags with two different mesh sizes (0.04 mm and 3 mm) was conducted to investigate the contribution of soil fauna to the loss of foliar litter mass in winter from November 2013 to April 2014 along the upper reaches of the Minjiang River. Two litter types of the dominant species were selected in each ecosystem: cypress (Cupressus chengiana) and oak (Quercus baronii) in ecotone; cypress (Cupressus chengiana) and clovershrub (Campylotropis macrocarpa) in dry valley; and fir (Abies faxoniana) and birch (Betula albosinensis) in montane forest. Over one winter incubation, foliar litter lost 6.0%-16.1%, 11.4%-26.0%, and 6.4%-8.5% of initial mass in the ecotone, dry valley and montane forest, respectively. Soil fauna showed obvious contributions to the loss of foliar litter mass in all of the ecosystems. The highest contribution (48.5%-56.8%) was observed in the ecotone, and the lowest contribution (0.4%-25.8%) was observed in the montane forest. Compared with other winter periods, thawing period exhibited higher soil fauna contributions to litter mass loss in ecotone and dry valley, but both thawing period and freezing period displayed higher soil fauna contributions in montane forest. Statistical analysis demonstrated that the contribution of soil fauna was significantly correlated with temperature and soil moisture during the winter-long incubation. These results suggest that temperature might be the primary control factor in foliar litter decomposition, but more active soil fauna in the ecotone could contribute more in litter decomposition and

  6. Contribution of Soil Fauna to Foliar Litter-Mass Loss in Winter in an Ecotone between Dry Valley and Montane Forest in the Upper Reaches of the Minjiang River.

    Directory of Open Access Journals (Sweden)

    Yan Peng

    Full Text Available Litter decomposition during winter can provide essential nutrients for plant growth in the subsequent growing season, which plays important role in preventing the expansion of dry areas and maintaining the stability of ecotone ecosystems. However, limited information is currently available on the contributions of soil fauna to litter decomposition during winter in such ecosystems. Therefore, a field experiment that included litterbags with two different mesh sizes (0.04 mm and 3 mm was conducted to investigate the contribution of soil fauna to the loss of foliar litter mass in winter from November 2013 to April 2014 along the upper reaches of the Minjiang River. Two litter types of the dominant species were selected in each ecosystem: cypress (Cupressus chengiana and oak (Quercus baronii in ecotone; cypress (Cupressus chengiana and clovershrub (Campylotropis macrocarpa in dry valley; and fir (Abies faxoniana and birch (Betula albosinensis in montane forest. Over one winter incubation, foliar litter lost 6.0%-16.1%, 11.4%-26.0%, and 6.4%-8.5% of initial mass in the ecotone, dry valley and montane forest, respectively. Soil fauna showed obvious contributions to the loss of foliar litter mass in all of the ecosystems. The highest contribution (48.5%-56.8% was observed in the ecotone, and the lowest contribution (0.4%-25.8% was observed in the montane forest. Compared with other winter periods, thawing period exhibited higher soil fauna contributions to litter mass loss in ecotone and dry valley, but both thawing period and freezing period displayed higher soil fauna contributions in montane forest. Statistical analysis demonstrated that the contribution of soil fauna was significantly correlated with temperature and soil moisture during the winter-long incubation. These results suggest that temperature might be the primary control factor in foliar litter decomposition, but more active soil fauna in the ecotone could contribute more in litter

  7. Regional and geomorphic influence on the productivity, composition, and structure of oak ecosystems in the western central hardwoods region

    Science.gov (United States)

    Amber M. Steele; John M. Kabrick; Randall J. Miles

    2013-01-01

    The steeply dissected glaciated landscapes of the Chariton River Hills Ecological Subsection (CRHES) in northern Missouri have extensive, but largely unmanaged, oak forests that are relatively unstudied. There is increasing interest in these forests for oak ecosystem restoration, ecological site description, and production of oak timber for biofuels. Our objectives...

  8. 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

  9. 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

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

    Directory of Open Access Journals (Sweden)

    C. Bastianelli

    2017-07-01

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

  11. 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....

  12. DO3SE modelling of soil moisture to determine ozone flux to forest trees

    Directory of Open Access Journals (Sweden)

    M. Schaub

    2012-06-01

    Full Text Available The DO3SE (Deposition of O3 for Stomatal Exchange model is an established tool for estimating ozone (O3 deposition, stomatal flux and impacts to a variety of vegetation types across Europe. It has been embedded within the EMEP (European Monitoring and Evaluation Programme photochemical model to provide a policy tool capable of relating the flux-based risk of vegetation damage to O3 precursor emission scenarios for use in policy formulation. A key limitation of regional flux-based risk assessments has been the assumption that soil water deficits are not limiting O3 flux due to the unavailability of evaluated methods for modelling soil water deficits and their influence on stomatal conductance (gsto, and subsequent O3 flux. This paper describes the development and evaluation of a method to estimate soil moisture status and its influence on gsto for a variety of forest tree species. This DO3SE soil moisture module uses the Penman-Monteith energy balance method to drive water cycling through the soil-plant-atmosphere system and empirical data describing gsto relationships with pre-dawn leaf water status to estimate the biological control of transpiration. We trial four different methods to estimate this biological control of the transpiration stream, which vary from simple methods that relate soil water content or potential directly to gsto, to more complex methods that incorporate hydraulic resistance and plant capacitance that control water flow through the plant system. These methods are evaluated against field data describing a variety of soil water variables, gsto and transpiration data for Norway spruce (Picea abies, Scots pine (Pinus sylvestris, birch (Betula pendula, aspen (Populus tremuloides, beech (Fagus sylvatica and holm oak (Quercus ilex collected from ten sites across Europe and North America. Modelled estimates of these variables show consistency with observed data when applying the simple empirical methods, with the timing and

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

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    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.

  14. 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.

  15. 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%

  16. Biological properties of soils of former forest fires in Samosir Regency of North Sumatera

    Directory of Open Access Journals (Sweden)

    D. Elfiati

    2016-04-01

    Full Text Available A study that was aimed to identify the impact of forest fires on the biological properties of soils was carried out at former forest fire areas in Samosir Regency of North Sumatera. Soil samples were collected from former forest fire areas of 2014, 2013, 2012, 2011, 2010. The composite soil samples were collected systematically using diagonal method as much as 5 points in each period of fire. The soil samples were taken at three plots measuring 20 x 20 m 0-20 cm depth. Soil biological properties observed were soil organic C content, total number of microbes, abundance of arbuscular mycorrhizal fungi, phosphate solubilizing microbes, and soil microbial activity. The results showed that organic C content ranged from 0.75 to 2.47% which included criteria for very low to moderate. Arbuscular mycorrhizal fungi spores were found belonging to the genus of Glomus and Acaulospora. Spore number increased with the fire period ranging from 45 spores (forest fire in 2014 to 152 spores (forest fire in 2010. The total number of microbes obtained ranged from 53.78 x 107 cfu/mL (forest fire in 2010 to 89.70 x107 cfu/mL (forest fire in 2013. It was found 29 isolates of phosphate solubilizing microbes that consisted of 14 bacterial isolates and 15 fungi isolates with densities ranging from 27.642 x105 cfu/mL (forest fires in 2014 to 97.776 x 105 cfu/ mL (forest fires in 2011. The isolates of phosphate solubilizing bacteria identified consisted of Pseudomonas, Flavobacterium, Staphylococcus, and Mycobacterium genus, whereas the isolates of phosphate solubilizing fungi obtained consisted of Aspergillus and Penicillium genus. Soil respiration ranged from 2.14 kg / day (forest fire in 2010 up to 3.71 kg / day (forest fire in 2013. The varied results were greatly influenced by the type or form of the fires and intensity of fires. In the study area the type or form of the fires were canopy fires with low intensity.

  17. 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.

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

    Science.gov (United States)

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

    2018-03-01

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

  19. 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...

  20. 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