WorldWideScience

Sample records for subalpine coniferous plantations

  1. [Dynamics of species diversity in artificial restoration process of subalpine coniferous forest].

    Science.gov (United States)

    Wu, Yan; Liu, Qing; He, Hai; Lin, Bo

    2004-08-01

    Through plot investigation and by adopting the concept of space as a substitute for time, the developments of species diversity of trees, shrubs and herbaceous plants in subalpine coniferous plantations at different restoration stages were studied, and the correlation coefficients of species in each layer were discussed. The results indicated that in the restoration process, the species richness, diversity and evenness in subalpine coniferous plantations were gradually increased in a fluctuating way. The restoration process of Picea asperata plantations showed a tendency of development that in favor of resuming species diversity. The indices of species richness (species number and Margalef index) and species diversity (Shannon-Wiener index and Simpson index) of trees increased rapidly from the early stages of plantation establishment to the stage of canopy closing (about 30 yr of stand age) and then presented a tendency of decrease with some slight fluctuations, while the index of species evenness showed a periodical rising trend. For the shrub layer, the indices of species richness (Simpson index and Macintosh index) gradually increased with increasing restoration years, whereas the indices of species diversity (Shannon-Wiener index) decreased in the early stages, sharply increased during the stages of canopy closing, and then slowly decreased, which exhibited a tendency of high-->low-->high. In the layer of herbaceous plants, the indices of species richness (Margalef index and number of species) and species diversity (Simpson index, Macintosh index and Shannon-Wiener index) presented a trend of decrease in the early stages of plantations establishment to canopy closing and increased later on. During this process, herbaceous species and their life forms changed greatly, with shade tolerant species gradually substituting the intolerant species. Among the plantations of different stand ages, the average correlation coefficients of trees, shrubs and herbaceous

  2. Rehabilitation of monotonous exotic coniferous plantations: A case study of spontaneous establishment of different tree species

    NARCIS (Netherlands)

    Jonásová, M.; Hees, van A.F.M.; Prach, K.

    2006-01-01

    Conversion of plantations of exotic coniferous species, such as Norway spruce (Picea abies), Douglas fir (Pseudotsuga menziesii) and Sitka spruce (Picea sitchensis), into more natural woodland is intended in two national parks in the province of Drenthe, The Netherlands. For that purpose, artificial

  3. Drivers of the composition and diversity of carabid functional traits in UK coniferous plantations

    Science.gov (United States)

    Spake, Rebecca; Barsoum, Nadia; Newton, Adrian C.; Doncaster, C. Patrick

    2016-01-01

    Functional diversity (FD) is increasingly used as a metric to evaluate the impact of forest management strategies on ecosystem functioning. Management interventions that aim to maximise FD require knowledge of multiple environmental drivers of FD, which have not been studied to date in temperate coniferous production forests. We quantified the relative importance of abiotic (forest management) and biotic (ground vegetation community) drivers of carabid FD and trait distribution in 44 coniferous plantation forest stands across the UK. Carabid FD declined with canopy cover and carabid body length correlated negatively with the percentage of open semi-natural area surrounding a plot. We conclude that forest management could enhance carabid FD through initiatives that emulate natural disturbance regimes through gap creation. We found that neither functional nor taxonomic metrics of vegetation diversity correlated with carabid FD, suggesting that restoration of plant communities, a major goal of forest restoration efforts, will not necessarily enhance carabid FD in coniferous plantations. PMID:26865748

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

    Directory of Open Access Journals (Sweden)

    V. V. Tarakanov

    2014-02-01

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

  5. The influence of changes in soil moisture in association with geomorphic change on the formation of a subalpine coniferous forest on Mt. Akita-Komagatake, northern Japan

    Science.gov (United States)

    Konno, A.

    2015-12-01

    The coniferous forest (largely composed of Abies mariesii) is presently the typical vegetation of the subalpine zone in Japan. Pollen analysis revealed that few A. mariesii were present during the last glacial period, and the species began to expand to the subalpine zone during the Holocene (Morita, 1992). However, on Mt. Akita-Komagatake in northern Japan, the expected predominance of A. mariesii is not extensively observed, and the predominant vegetation is instead the dwarf bamboo (Sasa kurilensis). It is unknown why the area under coniferous forest is small in this region. Therefore, I examined this issue from the perspectives of (1) distribution of vegetation, (2) geomorphology, (3) soil moisture, and (4) vegetation history. (1) Precise digital elevation model data and photographic interpretation showed that this coniferous forest was densely distributed in a flat segment considered to be formed by a landslide; (2) this landslide is thought to have occurred up to 3,699 ± 26 yr BP because a boring-core specimen from the landslide included the AK-3 tephra layer (2,300-2,800 yr BP: Wachi et al, 1997) and the radiocarbon date of the lowermost humic soil layer was 3,699 ± 26 yr BP; (3) the soil in the forest area had higher volumetric water content than that in the non-forest area; and (4) phytolith analysis revealed that the main species in the study site was initially dwarf bamboo, but coniferous forest replaced it after the Towada-a tephra (1035 cal. BP, Machida and Arai, 1992) layer fell. These results suggest that soil water conditions changed because of the formation of the flat segment by the landslide, and the coniferous forest was consequently established. However, the landslide only indirectly affected the formation of the coniferous forest, because the forest developed over several thousand years after the landslide occurred. In other words, more direct reasons for the establishment of the coniferous forest may involve changes in soil moisture. This

  6. Carbon and nitrogen status of decomposing roots in three adjacent coniferous plantations

    Directory of Open Access Journals (Sweden)

    Jaeyeob Jeong

    2014-07-01

    Full Text Available This study evaluated the carbon (C and nitrogen (N status of decomposing roots in three adjacent plantations consisting of one deciduous (larch: Larix leptolepis and two evergreen (red pine: Pinus densiflora; rigitaeda pine: P. rigitaeda species planted in the same year (1963 under similar site conditions. The mass loss rates and C and N status of three diameter classes of roots (UF < 2 mm, F 2-5 mm, CF 5-10 mm in diameter were examined in the upper 15 cm of the mineral soil using in situ buried root bags for 496 days.The remaining mass of decomposing roots was significantly higher for larch (69.0% than for red pine (59.6% or rigitaeda pine (59.1% over 496 days. The mass loss rates of decomposing roots did not differ significantly among the three root diameter classes, but the C and N status of decomposing roots was affected by the tree species. The larch roots showed low C concentrations but high N concentrations, C and N remaining compared to the pine roots over the study period. The results indicate that the substrate quality indicators of roots were not attributed to the mass loss rates, C and N status of decomposing roots in three coniferous tree species grown under similar environmental conditions.

  7. [Dynamic changes of topsoil organic carbon in subalpine spruce plantation at different succession stages in western Sichuan Province].

    Science.gov (United States)

    Jiang, Fa-Yan; Sun, Hui; Lin, Bo; Liu, Qing

    2009-11-01

    Soil samples at 0-30 cm depth were collected from the primary spruce (Picea asperata) forest and its plantations at different succession stages (22-, 47-, and 65-year-old) in subalpine zone of western Sichuan Province to study the dynamic changes of soil organic carbon stock and labile organic carbon content. The soil total organic carbon (TOC) stocks in 0-10, 10-20, and 20-30 cm soil layers decreased from 95.87, 79.08, and 71.55 t x hm(-2) in 22-year-old plantation to 56.12, 34.75, and 31.06 t x hm(-2) in 65-year-old plantation, respectively, and the TOC stocks in these soil layers in 47 and 65-year-old plantations were less than those (88.08, 71.16 and 64.81 t x hm(-2), respectively) in primary forest. The easily oxidizable organic carbon (EOC) contents in 0-10, 10-20, and 20-30 cm soil layers decreased from 35.89, 26.91, and 26.00 g x kg(-1) in primary forest to 20.25, 14.50, and 12.36 g x kg L(-1) in 65-year-old plantation, the microbial biomass carbon (MBC) contents decreased from 524.44, 273.26, and 257.97 mg x kg(-1) in primary forest to 312.41, 186.95, and 152.18 mg x kg(-1) in 65-year-old plantation, and the particulate organic carbon (POC) contents decreased from 40.23, 27.10, and 19.55 g x kg(-1) in primary forest to 12.33, 7.31, and 5.32 g x kg(-1) in 65-year-old plantation, respectively. The results suggested that within the long succession period of primary P. asperata forest to its plantations in the subalpine zone of western Sichuan Province, soil TOC and labile organic carbon were in the state of net consumption.

  8. Mean wind patterns and snow depths in an alpine-subalpine ecosystem as measured by damage to coniferous trees

    Science.gov (United States)

    G. L. Wooldridge; R. C. Musselman; R. A. Sommerfeld; D. G. Fox; B. H. Connell

    1996-01-01

    1. Deformations of Engelmann spruce and subalpine fir trees were surveyed for the purpose of determining climatic wind speeds and directions and snow depths in the Glacier Lakes Ecosystem Experiments Site (GLEES) in the Snowy Range of southeastern Wyoming, USA. Tree deformations were recorded at 50- and 100-m grid intervals over areas of c. 30 ha and 300 ha,...

  9. [Characteristics of soil respiration in artificial restoration process of subalpine coniferous forest in eastern Qinghai-Tibet plateau].

    Science.gov (United States)

    Zhou, Fei-Fei; Lin, Bo; Liu, Qing

    2009-08-01

    By the method of infrared CO2 determination in closed dynamic chamber system, the soil respiration in natural spruce forest, and 22-, 35-and 65-year old spruce plantations in eastern Qinghai-Tibet plateau was measured in situ, and the soil heterotrophic and autotrophic respiration was differentiated by entrenchment. In the four spruce forests, soil respiration rate had a significant positive exponential correlation with the soil temperature at depth 5 cm, but less correlation with the soil moisture content at the same depth. The annual soil respiration flux was 792.08-1070.20 g C x m(-2) x a (-1), and decreased in the order of natural spruce forest > 22-year old spruce plantation > 65-year old spruce plantation >35-year old spruce plantation. The annual soil autotrophic and heterotrophic respiration fluxes were 253.36-357.05 g C x m(-2) x a(-1) and 538.69-703.82 g C x m(-2) x a(-1), respectively, and had the same variation trend as the annual soil respiration flux. The Q10 value of soil respiration in 22-, 35-, and 65-year old spruce plantations and in natural spruce forest in growth season (from Nov. 2007 to Mar. 2008) and non-growth season (from Apr. 2008 to Oct. 2008) were 4.59, 6.54, 4.77, and 3.18, and 4.17, 4.66, 3.11, and 2.74, respectively. Except that in 22-year old spruce plantation, the Q10 value was decreased with increasing restoration year, and was obviously higher in non-growth season than in growth season.

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

    Science.gov (United States)

    Zhang, W.-J.; Wang, H.-M.; Yang, F.-T.; Yi, Y.-H.; Wen, X.-F.; Sun, X.-M.; Yu, G.-R.; Wang, Y.-D.; Ning, J.-C.

    2011-06-01

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

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

    Directory of Open Access Journals (Sweden)

    W.-J. Zhang

    2011-06-01

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

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

    Science.gov (United States)

    Li, Shuaifeng; Su, Jianrong; Liu, Wande; Lang, Xuedong; Huang, Xiaobo; Jia, Chengxinzhuo; Zhang, Zhijun; Tong, Qing

    2015-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Shuaifeng Li

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

  14. Modeling the impact of drought on canopy carbon and water fluxes for a subtropical evergreen coniferous plantation in southern China through parameter optimization using an ensemble Kalman filter

    Directory of Open Access Journals (Sweden)

    W. Ju

    2010-03-01

    Full Text Available Soil and atmospheric water deficits have significant influences on CO2 and energy exchanges between the atmosphere and terrestrial ecosystems. Model parameterization significantly affects the ability of a model to simulate carbon, water, and energy fluxes. In this study, an ensemble Kalman filter (EnKF and observations of gross primary productivity (GPP and latent heat (LE fluxes were used to optimize model parameters significantly affecting the calculation of these fluxes for a subtropical coniferous plantation in southeastern China. The optimized parameters include the maximum carboxylation rate (Vcmax, the slope in the modified Ball-Berry model (M and the coefficient determining the sensitivity of stomatal conductance to atmospheric water vapor deficit (D0. Optimized Vcmax and M showed larger variations than D0. Seasonal variations of Vcmax and M were more pronounced than the variations between the two years. Vcmax and M were associated with soil water content (SWC. During dry periods, SWC at the 20 cm depth explained 61% and 64% of variations of Vcmax and M, respectively. EnKF parameter optimization improved the simulations of GPP, LE and SH, mainly during dry periods. After parameter optimization using EnKF, the variations of GPP, LE and SH explained by the model increased by 1% to 4% at half-hourly steps and by 3% to 5% at daily time steps. Further efforts are needed to differentiate the real causes of parameter variations and improve the ability of models to describe the change of stomatal conductance with net photosynthesis rate and the sensitivity of photosynthesis capacity to soil water stress under different environmental conditions.

  15. Identification of coniferous woods

    Science.gov (United States)

    B. Francis Kukachka

    1960-01-01

    The identification of coniferous woods is generally regarded as being more difficult than for the hardwood species. This is due to the fact that conifers are more elemental in their structure and, as a consequence, the number of diagnostic features that may he employed is proportionately smaller. Instructions are given here in the sequential use of primary diagnostic...

  16. Soil Respiration at Different Stand Ages (5, 10, and 20/30 Years) in Coniferous (Pinus tabulaeformis Carrière) and Deciduous (Populus davidiana Dode) Plantations in a Sandstorm Source Area

    DEFF Research Database (Denmark)

    Zhao, Xin; Li, Fadong; Zhang, Wanjun

    2016-01-01

    Understanding the effects of stand age and forest type on soil respiration is crucial for predicting the potential of soil carbon sequestration. Thus far, however, there is no consensus regarding the variations in soil respiration caused by stand age and forest type. This study investigated soil...... that mean soil respiration in the 5-, 10-, and 20/30-year-old plantations was 3.37, 3.17, and 2.99 μmol·m−2·s−1 for P. tabulaeformis and 2.92, 2.85, and 2.57 μmol·m−2·s−1 for P. davidiana, respectively. Soil respiration decreased with stand age for both species. There was no significant difference in soil...... respiration between the two plantation species at ages 5 and 10 years (p > 0.05). Temperature sensitivity of soil respiration, which ranged from 1.85–1.99 in P. tabulaeformis and 2.20–2.46 in P. davidiana plantations, was found to increase with stand age. Temperature sensitivity was also significantly higher...

  17. Shady Plantations

    DEFF Research Database (Denmark)

    Hastrup, Frida

    2011-01-01

    This article explores practices of protection played out in a coastal plantation in a village in Tamil Nadu. I argue that these practices are articulations of different but coexisting theorizations of shelter, and that the plantation can be seen as that which emerges at the intersections between...

  18. Armillaria species in coniferous stands

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    Anna Żółciak

    2013-12-01

    Full Text Available Identification of the Armillaria species in selected coniferous stands (Scots pine stands, Norway spruce stands and fir stands was the aim of the work carried out on the basis of mating tests and consideration of macroscopic traits of fruit-bodies. One species of Armillaria [A. ostoyae (Romagnesi Herink] was found in Scots pine stands, three species [A. ostoyae, A. cepistipes Velenovský and A. borealis Marxmüller et Korhonen] were found in Norway spruce stands and two species [A. ostoyae and A. cepistipes] were found in fir stands.

  19. Airflow patterns in a small subalpine basin

    Science.gov (United States)

    G. Wooldridge; R. Musselman; B. Connell; D. Fox

    1992-01-01

    A study of mean wind speeds and directions has been completed in the Snowy Range of Southern Wyoming, U.S.A. It was conducted in a subalpine ecosystem at an altitude of 3 200 m to 3 400 m above sea level during the summers of 1988 and 1989. Indexes of deformation and axes of asymmetry due to wind shaping of Engelmann spruce (Picea engelmannii) and subalpine fir (Abies...

  20. Stable soil organic carbon is positively linked to microbial-derived compounds in four plantations of subtropical China

    Science.gov (United States)

    Wang, H.; Liu, S.; Chang, S. X.; Wang, J.; Shi, Z.; Huang, X.; Wen, Y.; Lu, L.; Cai, D.

    2013-11-01

    Indigenous broadleaf plantations are increasingly being developed to substitute pure coniferous plantations to increase biodiversity and soil fertility in subtropical China. To assess how plantation types affect soil organic carbon (SOC) chemical composition, we used the solid-state 13C nuclear magnetic resonance spectroscopy with cross-polarization and magic-angle spinning (CPMAS-NMR) technique to analyze SOC and litter C chemical compositions in a coniferous (Pinus massoniana) and three broadleaf (Castanopsis hystrix, Michelia macclurei and Mytilaria laosensis) plantations in subtropical China. Soil microbial community composition and biomass were investigated with the phospholipid fatty acids (PLFAs) and chloroform fumigation-extraction methods, respectively. The SOC chemical composition varied with plantation type, with 34% of the SOC found in the alkyl C fraction in the P. massoniana plantation compared to < 28% in the broadleaf plantations. The amount of total PLFAs, bacterial and particularly the gram-positive bacterial population size, and microbial C / N ratio were correlated with the alkyl C content and alkyl C / O-alkyl C ratio. However, the soil alkyl C content was not correlated with the recalcitrance of leaf litter or fine roots. We thus suggest that the stable SOC composition could be attributable to the contribution of microbial-derived C compounds, rather than leaf litter or fine root quality or a direct flux of C from recalcitrant litter materials to more stable SOC pools.

  1. Antibacterial and Antifungal Effects of Essential Oils from Coniferous Trees

    National Research Council Canada - National Science Library

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

    2004-01-01

    .... In the present study, we investigated the antibacterial and antifungal effects of essential oils extracted from the coniferous species Pinus densiflora, Pinus koraiensis, and Chamaecyparis obtusa...

  2. Ecosystem carbon stock influenced by plantation practice: implications for planting forests as a measure of climate change mitigation.

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    Chengzhang Liao

    Full Text Available Uncertainties remain in the potential of forest plantations to sequestrate carbon (C. We synthesized 86 experimental studies with paired-site design, using a meta-analysis approach, to quantify the differences in ecosystem C pools between plantations and their corresponding adjacent primary and secondary forests (natural forests. Totaled ecosystem C stock in plant and soil pools was 284 Mg C ha(-1 in natural forests and decreased by 28% in plantations. In comparison with natural forests, plantations decreased aboveground net primary production, litterfall, and rate of soil respiration by 11, 34, and 32%, respectively. Fine root biomass, soil C concentration, and soil microbial C concentration decreased respectively by 66, 32, and 29% in plantations relative to natural forests. Soil available N, P and K concentrations were lower by 22, 20 and 26%, respectively, in plantations than in natural forests. The general pattern of decreased ecosystem C pools did not change between two different groups in relation to various factors: stand age ( or = 25 years, stand types (broadleaved vs. coniferous and deciduous vs. evergreen, tree species origin (native vs. exotic of plantations, land-use history (afforestation vs. reforestation and site preparation for plantations (unburnt vs. burnt, and study regions (tropic vs. temperate. The pattern also held true across geographic regions. Our findings argued against the replacement of natural forests by the plantations as a measure of climate change mitigation.

  3. [Caloric value and ash content of dominant plants in plantation communities in Heshan of Guangdong, China].

    Science.gov (United States)

    Zeng, Xiao-ping; Cai, Xi-an; Zhao, Ping; Rao, Xing-quan

    2009-03-01

    Different parts of twenty dominant plant species in five plantation communities on the subtropical hilly lands in Heshan of Gunagdong as well as the litters from three of the five plantation communities were sampled, and their gross caloric value (GCV) and ash content were measured by using a PARR-1281 oxygen bomb calorimeter and a muffle furnace. Based on the measurements, the ash-free caloric value (AFCV) of the samples was calculated, and the characteristics of caloric value and ash content of the samples, according to plant part, individual, and plant growth form, were analyzed. The results showed that the GCV and AFCV of leaf, branch, stem wood, stem bark, and root were in the range of 10.7-22.17 kJ x g(-1) and 13.89-23.04 kJ x g(-1), respectively. The GCV and AFCV of leaf were significantly higher than those of other parts (P shrub layer (19.46 kJ x g(-1) > herb layer (18.77 kJ x g(-1)), with indigenous coniferous tree (19.86 kJ x g(-1)) > indigenous broad-leaved tree (19.55 kJ x g(-1)) > exotic eucalyptus (19.18 kJ x g(-1)), while the mean ash content was just the opposite. In Acacia mangium, coniferous, and Schima plantation communities, the GCV and AFCV of litters were higher than those of various plant parts (P mangium and coniferous plantations had higher mean GCV and AFCV than the litters and fresh leaves of tree layer, while the fresh leaves of tree layer in Schima plantation showed higher mean GCV and AFCV.

  4. Invasion of subalpine meadows by lodgepole pine in Yellowstone National Park, Wyoming, USA

    Energy Technology Data Exchange (ETDEWEB)

    Jakubos, B.; Romme, W.H. (Fort Lewis College, Durango, CO (United States))

    1993-11-01

    Many of the dry and mesic subalpine meadows in Yellowstone National Park are bordered by bands of small lodgepole pine trees. The authors asked whether these stands of small trees represent a directional process of meadow invasion, or alternatively, (1) small patches of postfire succession or; (2) more-or-less stable populations of trees having small stature because of adverse site conditions. Transect studies revealed that the bands of small trees were consistently younger than adjacent forest stands of obvious fire origin, that they lacked any evidence of fire, and that the trees were progressively younger as they approached the meadow. Soils under the young trees generally were more similar to meadow soils than to coniferous forest soils. The authors concluded, therefore, that meadow invasion has been occurring as a directional process since at least the mid- to late 1800s. Frequency of tree establishment in two dry meadows was positively correlated with mean June temperature and total summer precipitation (R[sup 2] = 0.49, P<0.0001, multiple stepwise regression). Thus, the major cause of tree invasion into dry meadows appears to be a regional climatic trend towards warmer and wetter growing seasons since the end of the Little Ice Age. Tree establishment in two mesic meadows was more weakly and inconsistently correlated with weather variables. Thus, the mechanism of invasion of mesic meadows may involve interactions of episodic seed crops and microhabitat changes at the forest border, as well as regional climatic variability. 30 refs., 7 figs., 1 tab.

  5. Hydrological Features on Subalpine Forest Zone in the East of Qinghai-Tibet Plateau

    Science.gov (United States)

    Zhong, X.; Cheng, G.; Guo, W.

    2008-12-01

    The Hengduan mountain chains of China is situated on the east of Qinghai-Tibet Plateau with area of more than 400,000 km2. Mountains and rivers run through in north-south direction, and are collocated side by side on east-west. Elevation difference between ridges and valleys has great disparity, normally of 1000-2500m, so the vertical zones of vegetation are very distinct. Subalpine coniferous forest zone, mainly composed of fir (Abies) and spruce (Picea), is on altitude of 2800-4200m, which is a chief component of the forested area in southwest China, and an important region for water conservation of several international rivers inlcuding Nujiang River and Lancangjiang River, as well as the world-famous Changjiang River. Thus, it has both theoretical and practical significance to study hydrological process and laws of forest in this region. The study area is located at the Gongga Mountain, on the east edge of the Hengduan mountain chains. Elevation of the main peak is 7556m, and elevation difference between ridge and valley on the eastern slope is 6400m. An ecological observation station was built at altitude of 3000m on the eastern slope of Gongga Mountain in 1988, mainly for alpine ecology and forest hydrology research. Based on the analysis of 20- years observation data from this station, it is revealed that hydrological process of forest in this area has several features as follows: (1) Canopy interception of primitive fir (Abies) forest is obviously greater than other tree species, and interception rate is 30-40%. Maximal canopy interception of one-time precipitation of primitive fir forest is commonly 2-5mm. According to observation data of canopy interception, a conceptual model of canopy interception of fir forest is established: R=1.69[(1-exp(-0.41P))+0.19P (P is precipitation in mm); (2) Natural valid moisture holding capacity in layer of moss-decayed wood and leaves beneath trees is up to 5.6mm. Porosity in soil surface layer and non-capillary porosity

  6. Above- and below-ground carbon stocks in an indigenous tree (Mytilaria laosensis) plantation chronosequence in subtropical China.

    Science.gov (United States)

    Ming, Angang; Jia, Hongyan; Zhao, Jinlong; Tao, Yi; Li, Yuanfa

    2014-01-01

    More than 60% of the total area of tree plantations in China is in subtropical, and over 70% of subtropical plantations consist of pure stands of coniferous species. Because of the poor ecosystem services provided by pure coniferous plantations and the ecological instability of these stands, a movement is under way to promote indigenous broadleaf plantation cultivation as a promising alternative. However, little is known about the carbon (C) stocks in indigenous broadleaf plantations and their dependence on stand age. Thus, we studied above- and below-ground biomass and C stocks in a chronosequence of Mytilaria laosensis plantations in subtropical China; stands were 7, 10, 18, 23, 29 and 33 years old. Our assessments included tree, shrub, herb and litter layers. We used plot-level inventories and destructive tree sampling to determine vegetation C stocks. We also measured soil C stocks by analyses of soil profiles to 100 cm depth. C stocks in the tree layer dominated the above-ground ecosystem C pool across the chronosequence. C stocks increased with age from 7 to 29 years and plateaued thereafter due to a reduction in tree growth rates. Minor C stocks were found in the shrub and herb layers of all six plantations and their temporal fluctuations were relatively small. C stocks in the litter and soil layers increased with stand age. Total above-ground ecosystem C also increased with stand age. Most increases in C stocks in below-ground and total ecosystems were attributable to increases in soil C content and tree biomass. Therefore, considerations of C sequestration potential in indigenous broadleaf plantations must take stand age into account.

  7. Investigation of post-fire natural regeneration in forest plantations of Pinus sylvestris and Larix decidua on the Northern slopes of Rila mountain

    Directory of Open Access Journals (Sweden)

    Ibrahim Molla

    2016-12-01

    Full Text Available Wildfires alter both the vegetation and the soil properties, thus changing the conditions of their regeneration. Each year, forest fires impact significant areas within the lower forest zone, where the coniferous plantations, especially Scots pine plantations are deteriorated. The natural forest recovery processes in fire-affected areas are still insufficiently studied in Bulgaria. Therefore, the aim of the present study was to investigate the possibility of a natural post-fire regeneration of forest vegetation and the conditions, under which it was limited. The natural regeneration of coniferous plantations in the area of Dolna Banya (The Northern slopes of Rila Mt with dominant tree species of Scots pine (Pinus sylvestris L. (Object 1 and European larch (Larix decidua Mill. (Object 2 was studied four years after fire and was found to depend on the slope aspect, the micro-relief and soil humidity. It was found that on the South-western slopes, the diversity of broadleaves tree species recovery (birch, oak, sallow, aspen was higher in comparison with the coniferous (Scotch pine ones. On the Eastern slope, the regeneration of coniferous prevailed over that of broadleaves. On the ridges, the regeneration was the lowest one, while on the foot of the slopes was higher.

  8. Effects of elevated CO₂ and temperature on photosynthesis and leaf traits of an understory dwarf bamboo in subalpine forest zone, China.

    Science.gov (United States)

    Li, Yongping; Zhang, Yuanbin; Zhang, Xiaolu; Korpelainen, Helena; Berninger, Frank; Li, Chunyang

    2013-06-01

    The dwarf bamboo (Fargesia rufa Yi), growing understory in subalpine dark coniferous forest, is one of the main foods for giant panda, and it influences the regeneration of subalpine coniferous forests in southwestern China. To investigate the effects of elevated CO₂, temperature and their combination, the dwarf bamboo plantlets were exposed to two CO₂ regimes (ambient and double ambient CO₂ concentration) and two temperatures (ambient and +2.2°C) in growth chambers. Gas exchange, leaf traits and carbohydrates concentration were measured after the 150-day experiment. Elevated CO₂ significantly increased the net photosynthetic rate (Anet ), intrinsic water-use efficiency (WUEi ) and carbon isotope composition (δ¹³C) and decreased stomatal conductance (g(s)) and total chlorophyll concentration based on mass (Chl(m)) and area (Chl(a)). On the other hand, elevated CO₂ decreased specific leaf area (SLA), which was increased by elevated temperature. Elevated CO₂ also increased foliar carbon concentration based on mass (C(m)) and area (C(a)), nitrogen concentration based on area (N(a)), carbohydrates concentration (i.e. sucrose, sugar, starch and non-structural carbohydrates) and the slope of the A(net)-N(a) relationship. However, elevated temperature decreased C(m), C(a) and N(a). The combination of elevated CO₂ and temperature hardly affected SLA, C(m), C(a), N(m), N(a), Chl(m) and Chl(a). Variables Anet and Na had positive linear relationships in all treatments. Our results showed that photosynthetic acclimation did not occur in dwarf bamboo at elevated CO₂ and it could adjust physiology and morphology to enable the capture of more light, to increase WUE and improve nutritional conditions. Copyright © Physiologia Plantarum 2012.

  9. Sound-mapping a coniferous forest-Perspectives for biodiversity monitoring and noise mitigation.

    Directory of Open Access Journals (Sweden)

    Anthony Turner

    Full Text Available Acoustic diversity indices have been proposed as low-cost biodiversity monitoring tools. The acoustic diversity of a soundscape can be indicative of the richness of an acoustic community and the structural/vegetation characteristics of a habitat. There is a need to apply these methods to landscapes that are ecologically and/or economically important. We investigate the relationship between the acoustic properties of a coniferous forest with stand-age and structure. We sampled a 73 point grid in part of the UK's largest man-made lowland coniferous plantation forest, covering a 320ha mosaic of different aged stands. Forest stands ranged from 0-85 years old providing an age-gradient. Short soundscape recordings were collected from each grid point on multiple mornings (between 6am-11am to capture the dawn chorus. We repeated the study during July/August in 2014 and again in 2015. Five acoustic indices were calculated for a total of 889 two minute samples. Moderate relationships between acoustic diversity with forest stand-age and vegetation characteristics (canopy height; canopy cover were observed. Ordinations suggest that as structural complexity and forest age increases, the higher frequency bands (4-10KHz become more represented in the soundscape. A strong linear relationship was observed between distance to the nearest road and the ratio of anthropogenic noise to biological sounds within the soundscape. Similar acoustic patterns were observed in both years, though acoustic diversity was generally lower in 2014, which was likely due to differences in wind conditions between years. Our results suggest that developing these relatively low-cost acoustic monitoring methods to inform adaptive management of production landscapes, may lead to improved biodiversity monitoring. The methods may also prove useful for modelling road noise, landscape planning and noise mitigation.

  10. Sound-mapping a coniferous forest-Perspectives for biodiversity monitoring and noise mitigation.

    Science.gov (United States)

    Turner, Anthony; Fischer, Michael; Tzanopoulos, Joseph

    2018-01-01

    Acoustic diversity indices have been proposed as low-cost biodiversity monitoring tools. The acoustic diversity of a soundscape can be indicative of the richness of an acoustic community and the structural/vegetation characteristics of a habitat. There is a need to apply these methods to landscapes that are ecologically and/or economically important. We investigate the relationship between the acoustic properties of a coniferous forest with stand-age and structure. We sampled a 73 point grid in part of the UK's largest man-made lowland coniferous plantation forest, covering a 320ha mosaic of different aged stands. Forest stands ranged from 0-85 years old providing an age-gradient. Short soundscape recordings were collected from each grid point on multiple mornings (between 6am-11am) to capture the dawn chorus. We repeated the study during July/August in 2014 and again in 2015. Five acoustic indices were calculated for a total of 889 two minute samples. Moderate relationships between acoustic diversity with forest stand-age and vegetation characteristics (canopy height; canopy cover) were observed. Ordinations suggest that as structural complexity and forest age increases, the higher frequency bands (4-10KHz) become more represented in the soundscape. A strong linear relationship was observed between distance to the nearest road and the ratio of anthropogenic noise to biological sounds within the soundscape. Similar acoustic patterns were observed in both years, though acoustic diversity was generally lower in 2014, which was likely due to differences in wind conditions between years. Our results suggest that developing these relatively low-cost acoustic monitoring methods to inform adaptive management of production landscapes, may lead to improved biodiversity monitoring. The methods may also prove useful for modelling road noise, landscape planning and noise mitigation.

  11. Sound-mapping a coniferous forest—Perspectives for biodiversity monitoring and noise mitigation

    Science.gov (United States)

    Fischer, Michael; Tzanopoulos, Joseph

    2018-01-01

    Acoustic diversity indices have been proposed as low-cost biodiversity monitoring tools. The acoustic diversity of a soundscape can be indicative of the richness of an acoustic community and the structural/vegetation characteristics of a habitat. There is a need to apply these methods to landscapes that are ecologically and/or economically important. We investigate the relationship between the acoustic properties of a coniferous forest with stand-age and structure. We sampled a 73 point grid in part of the UK’s largest man-made lowland coniferous plantation forest, covering a 320ha mosaic of different aged stands. Forest stands ranged from 0–85 years old providing an age-gradient. Short soundscape recordings were collected from each grid point on multiple mornings (between 6am-11am) to capture the dawn chorus. We repeated the study during July/August in 2014 and again in 2015. Five acoustic indices were calculated for a total of 889 two minute samples. Moderate relationships between acoustic diversity with forest stand-age and vegetation characteristics (canopy height; canopy cover) were observed. Ordinations suggest that as structural complexity and forest age increases, the higher frequency bands (4-10KHz) become more represented in the soundscape. A strong linear relationship was observed between distance to the nearest road and the ratio of anthropogenic noise to biological sounds within the soundscape. Similar acoustic patterns were observed in both years, though acoustic diversity was generally lower in 2014, which was likely due to differences in wind conditions between years. Our results suggest that developing these relatively low-cost acoustic monitoring methods to inform adaptive management of production landscapes, may lead to improved biodiversity monitoring. The methods may also prove useful for modelling road noise, landscape planning and noise mitigation. PMID:29320514

  12. The push for plantations

    DEFF Research Database (Denmark)

    Thulstrup, Andreas Waaben; Casse, Thorkil; Nielsen, Thomas Theis

    2013-01-01

    We observe signs of social differentiation, where poor households end up serving as causal labour for the richer families on their acacia plantations. In addition, the poor can be rendered more vulnerable after becoming labourers, because they may not longer have an alternative source of income...

  13. Provenance variability in nursery growth of subalpine fir

    Science.gov (United States)

    Charlie Cartwright; Cheng Ying

    2011-01-01

    Subalpine fir (Abies lasiocarpa [Hook] Nutt.) is a wide-ranging, high-elevation species in the interior of British Columbia. It is commonly harvested for lumber, but replanting of it is limited. Some reticence is based upon wood quality and rate of growth, but there are also seed and nursery culturing difficulties. This study investigated seedling growth traits of 111...

  14. Using historical ecology to reassess the conservation status of coniferous forests in Central Europe.

    Science.gov (United States)

    Szabó, Péter; Kuneš, Petr; Svobodová-Svitavská, Helena; Švarcová, Markéta Gabriela; Křížová, Lucie; Suchánková, Silvie; Müllerová, Jana; Hédl, Radim

    2017-02-01

    Forests cover approximately one-third of Central Europe. Oak (Quercus) and European beech (Fagus sylvatica) are considered the natural dominants at low and middle elevations, respectively. Many coniferous forests (especially of Picea abies) occur primarily at midelevations, but these are thought to have resulted from forestry plantations planted over the past 200 years. Nature conservation and forestry policy seek to promote broadleaved trees over conifers. However, there are discrepancies between conservation guidelines (included in Natura 2000) and historical and palaeoecological data with regard to the distribution of conifers. Our aim was to bring new evidence to the debate on the conservation of conifers versus broadleaved trees at midelevations in Central Europe. We created a vegetation and land-cover model based on pollen data for a highland area of 11,300 km 2 in the Czech Republic and assessed tree species composition in the forests before the onset of modern forestry based on 18th-century archival sources. Conifers dominated the study region throughout the entire Holocene (approximately 40-60% of the area). Broadleaved trees were present in a much smaller area than envisaged by current ideas of natural vegetation. Rather than casting doubt on the principles of Central European nature conservation in general, our results highlight the necessity of detailed regional investigations and the importance of historical data in challenging established notions on the natural distribution of tree species. © 2016 Society for Conservation Biology.

  15. Fire history of coniferous riparian forests in the Sierra Nevada

    Science.gov (United States)

    K. Van de Water; M. North

    2010-01-01

    Fire is an important ecological process in many western U.S. coniferous forests, yet high fuel loads, rural home construction and other factors have encouraged the suppression of most wildfires. Using mechanical thinning and prescribed burning, land managers often try to reduce fuels in strategic areas with the highest fuel loads. Riparian forests, however, are often...

  16. Coniferous forest habitat types of central and southern Utah

    Science.gov (United States)

    Andrew P. Youngblood; Ronald L. Mauk

    1985-01-01

    A land-classification system based upon potential natural vegetation is presented for the coniferous forests of central and southern Utah. It is based on reconnaissance sampling of about 720 stands. A hierarchical taxonomic classification of forest sites was developed using the habitat type concept. Seven climax series, 37 habitat types, and six additional phases of...

  17. Soil erosion: perennial crop plantations

    NARCIS (Netherlands)

    Hartemink, A.E.

    2006-01-01

    Plantation agriculture is an important form of land-use in the tropics. Large areas of natural and regenerated forest have been cleared for growing oil palm, rubber, cocoa, coffee, and other perennial tree crops. These crops grown both on large scale plantations and by smallholders are important

  18. Disturbance and Stand Development of a Colorado Subalpine Forest

    OpenAIRE

    Veblen, Thomas T.; Hadley, Keith S; Reid, Marion S

    1991-01-01

    Stand development patterns were examined in an Engelmann spruce (Picea engelmannii), subalpine fir (Abies lasiocarpa) and lodgepole pine (Pinus contorta var. latifolia) forest in Rocky Mountain National Park in northern Colorado. Two old-growth stands (with fine-scale windthrows dominating dynamics) and a 260-yr-old post-fire stand were sampled for tree ages, sizes, growth, and replacement patterns in windthrow gaps. Visual assessment of frequency of growth releases in increment cores, and de...

  19. Evaluation of storage and filtration protocols for alpine/subalpine lake water quality samples

    Science.gov (United States)

    John L. Korfmacher; Robert C. Musselman

    2007-01-01

    Many government agencies and other organizations sample natural alpine and subalpine surface waters using varying protocols for sample storage and filtration. Simplification of protocols would be beneficial if it could be shown that sample quality is unaffected. In this study, samples collected from low ionic strength waters in alpine and subalpine lake inlets...

  20. Ozone and modeled stomatal conductance at a high elevation subalpine site in southeastern Wyoming

    Science.gov (United States)

    Robert C. Musselman; Karl F. Zeller; Nedialko T. Nikolov

    1998-01-01

    Ozone concentrations have been monitored at the Glacier Lakes Ecosystem Experiment Site (GLEES) in the Snowy Range of the Medicine Bow Mountains 55 km west of Laramie, Wyoming, USA. The site is located at 3,186 m elevation in a large subalpine meadow of a mature subalpine forest near timberline. Continuous ozone and meteorological monitoring are a part of the GLEES...

  1. Using stable water isotopes and borehole NMR to inform an ecohydrological model in a subalpine and upper montane catchment in the Rocky Mountains

    Science.gov (United States)

    Millar, D.; Parsekian, A.; Mercer, J.; Speckman, H. N.; Beverly, D.; Ewers, B. E.; Mackay, D. S.

    2016-12-01

    Recent work using stable water isotopes has revealed that vegetation across a range of different biomes preferentially take up tightly bound soil water over more mobile pools. This so called two water worlds hypothesis (TWWH) has important implications for hydrological modeling efforts in ecosystems where it holds true, since few if any ecohydrological models incorporate this phenomenon. Further, in ecosystems where the TWWH is supported, information regarding the proportion of soil water in the bound and mobile pools is necessary to inform plant-soil water dynamics in models. In this study, we investigate which soil water pools are used by dominant vegetation in an upper montane and subalpine catchment in the Rocky Mountains of southern Wyoming, and use this information to inform the Terrestrial Regional Ecosystem Exchange Simulator (TREES). Within each catchment, we test the TWWH using stable water isotope analyses in an upland coniferous forest and an adjacent, downgradient groundwater-supported wetland. The proportion of soil water in each pool within each ecosystem was inferred from borehole nuclear magnetic resonance (NMR). These field data are being incorporated into TREES, by partitioning plant water uptake between bound and mobile pools. NMR analyses were conducted in all four ecosystems down to a depth of approximately 75 cm and revealed that while mid growing season soil water content was approximately two-fold higher in the subalpine forest versus that of the upper montane forest, the vast majority of soil water, 86% on average, existed in the bound pool in both ecosystems. Alternatively, soils in both wetlands were saturated throughout their profiles, with a majority of the soil water existing in the mobile pool, 63% on average. These initial findings highlight the importance of bound soil water pools in both upland forests, as opposed to the wetlands, which had an abundance of water in both pools.

  2. A multi-proxy record of hydroclimate, vegetation, fire, and post-settlement impacts for a subalpine plateau, Central Rocky Mountains U.S.A

    Science.gov (United States)

    Anderson, Lesleigh; Brunelle, Andrea; Thompson, Robert S.

    2015-01-01

    Apparent changes in vegetation distribution, fire, and other disturbance regimes throughout western North America have prompted investigations of the relative importance of human activities and climate change as potential causal mechanisms. Assessing the effects of Euro-American settlement is difficult because climate changes occur on multi-decadal to centennial time scales and require longer time perspectives than historic observations can provide. Here, we report vegetation and environmental changes over the past ~13,000 years as recorded in a sediment record from Bison Lake, a subalpine lake on a high plateau in northwestern Colorado. Results are based on multiple independent proxies, which include pollen, charcoal, and elemental geochemistry, and are compared with previously reported interpretations of hydroclimatic changes from oxygen isotope ratios. The pollen data indicate a slowly changing vegetation sequence from sagebrush steppe during the late glacial to coniferous forest through the late Holocene. The most dramatic vegetation changes of the Holocene occurred during the ‘Medieval Climate Anomaly’ (MCA) and ‘Little Ice Age’ (LIA) with rapid replacement of conifer forest by grassland followed by an equally rapid return to conifer forest. Late Holocene vegetation responses are mirrored by changes in fire, lake biological productivity, and watershed erosion. These combined records indicate that subsequent disturbance related to Euro-American settlement, although perhaps significant, had acted upon a landscape that was already responding to MCA-LIA hydroclimatic change. Results document both rapid and long-term subalpine grassland ecosystem dynamics driven by agents of change that can be anticipated in the future and simulated by ecosystem models.

  3. Spectral Properties of Coniferous Forests: A Review of In Situ and Laboratory Measurements

    Directory of Open Access Journals (Sweden)

    Miina Rautiainen

    2018-01-01

    Full Text Available Coniferous species are present in almost all major vegetation biomes on Earth, though they are the most abundant in the northern hemisphere, where they form the northern tree and forest lines close to the Arctic Circle. Monitoring coniferous forests with satellite and airborne remote sensing is active, due to the forests’ great ecological and economic importance. We review the current understanding of spectral behavior of different components forming coniferous forests. We look at the spatial, directional, and seasonal variations in needle, shoot, woody element, and understory spectra in coniferous forests, based on measurements. Through selected case studies, we also demonstrate how coniferous canopy spectra vary at different spatial scales, and in different viewing angles and seasons. Finally, we provide a synthesis of gaps in the current knowledge on spectra of elements forming coniferous forests that could also serve as a recommendation for planning scientific efforts in the future.

  4. Fire, fuel composition and resilience threshold in subalpine ecosystem.

    Directory of Open Access Journals (Sweden)

    Olivier Blarquez

    Full Text Available BACKGROUND: Forecasting the effects of global changes on high altitude ecosystems requires an understanding of the long-term relationships between biota and forcing factors to identify resilience thresholds. Fire is a crucial forcing factor: both fuel build-up from land-abandonment in European mountains, and more droughts linked to global warming are likely to increase fire risks. METHODS: To assess the vegetation response to fire on a millennium time-scale, we analyzed evidence of stand-to-local vegetation dynamics derived from sedimentary plant macroremains from two subalpine lakes. Paleobotanical reconstructions at high temporal resolution, together with a fire frequency reconstruction inferred from sedimentary charcoal, were analyzed by Superposed Epoch Analysis to model plant behavior before, during and after fire events. PRINCIPAL FINDINGS: We show that fuel build-up from arolla pine (Pinus cembra always precedes fires, which is immediately followed by a rapid increase of birch (Betula sp., then by ericaceous species after 25-75 years, and by herbs after 50-100 years. European larch (Larix decidua, which is the natural co-dominant species of subalpine forests with Pinus cembra, is not sensitive to fire, while the abundance of Pinus cembra is altered within a 150-year period after fires. A long-term trend in vegetation dynamics is apparent, wherein species that abound later in succession are the functional drivers, loading the environment with fuel for fires. This system can only be functional if fires are mainly driven by external factors (e.g. climate, with the mean interval between fires being longer than the minimum time required to reach the late successional stage, here 150 years. CONCLUSION: Current global warming conditions which increase drought occurrences, combined with the abandonment of land in European mountain areas, creates ideal ecological conditions for the ignition and the spread of fire. A fire return interval of less

  5. Quantifying the Effects of Normalisation of Airborne LiDAR Intensity on Coniferous Forest Leaf Area Index Estimations

    National Research Council Canada - National Science Library

    You, Haotian; Wang, Tiejun; Skidmore, Andrew; Xing, Yanqiu

    2017-01-01

    .... In this paper, using two coniferous tree species (i.e., Scotch pine and Larch pine) as a case study, the effects of intensity normalisation on coniferous forest LAI estimations have, for the first time, been systematically examined and quantified...

  6. Comparative phytosocioogical investigation of subalpine alder thickets in southwestern Alaska and the North Pacific

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — We present the first vegetation analysis of subalpine alder (Alnus viridis) thickets in southwestern Alaska. The data are primarily from mesic, hilly and mountainous...

  7. Organic compounds in atmospheric aerosols from a Finnish coniferous forest

    Energy Technology Data Exchange (ETDEWEB)

    Anttila, P.; Rissanen, T.; Shimmo, M.; Kallio, M.; Hyoetylaeinen, T.; Riekkola, M.L. [Laboratory of Analytical Chemistry, Department of Chemistry, University of Helsinki (Finland); Kulmala, M. [Department of Physical Sciences, University of Helsinki (Finland)

    2005-07-01

    Atmospheric aerosol particles were collected with a high-volume sampler in a Finnish coniferous forest during the field campaign Quantification of Aerosol Nucleation in the European Boundary Layer (QUEST) in March-April 2003. Four chromatographic techniques were applied to characterise the organic composition of the samples, and to study variations in the concentrations of identified compounds. Among the nearly 160 organic compounds identified were n-alkanes, nalkanals, n-alkan-2-ones, n- alkanols, n-alkanoic acids, n-alkenoic acids, dicarboxylic acids, polyaromatic hydrocarbons, hopanes, streranes, terpenes and terpenoids. The observed variations in the concentrations of certain compounds were mostly explained by ambient temperature. Comparison of days when atmospheric new particle formation took place with days when the formation did not occur, however, revealed higher concentrations of long-chain n- alkanes (> C{sub 22}) and < C{sub 18} n-alkanoic acids on the particle formation days. (orig.)

  8. Recovery of Collembola in Pinus tabulaeformis plantations

    Science.gov (United States)

    Liang CHANG; Baifeng WANG; Xianghui LIU; Mac A. CALLAHAM; Feng GE

    2017-01-01

    Large areas of forest plantations have been developed in China. It is important to evaluate the soil fauna in plantations and the conditions needed for their recovery in view of the large areas of plantations in China. Three Pinus tabulaeformis forests, a 26-year-old plantation (P26) and a 45-year-old plantation (P45), exposed to clear-...

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

    Directory of Open Access Journals (Sweden)

    Kiedrowicz Agnieszka

    2016-06-01

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

  10. Climate, geography, and tree establishment in subalpine meadows of the Olympic Mountains, Washington, USA

    Science.gov (United States)

    Woodward, Andrea; Schreiner, Edward G.; Silsbee, D.G.

    1995-01-01

    Noticeable changes in vegetation distribution have occurred in the Pacific Northwest during the last century as trees have established in some subalpine meadows. To study the relationship of this process to climate, recently established trees were aged in six subalpine meadows in the Olympic Mountains, Washington. The sites represent three points along a steep precipitation gradient. Subalpine fir (Abies lasiocarpa) has been establishing at the dry end of the gradient, mountain hemlock (Tsuga mertensiana) at the wet end, and both species in the center. Establishment patterns were compared with deviations from the century-long average for these weather variables: winter precipitation, Palmer Drought Severity Index, and winter, October, and May temperatures. Results show that establishment occurred in dry areas when weather conditions were wetter than average, and in wet areas under drier than average conditions. Establishment at central sites did not show consistent relationships with climate. If future climatic conditions continue to warm, establishment of subalpine fir in subalpine meadows in dry areas may cease and mountain hemlock may resume in wet areas.

  11. Mercury in coniferous and deciduous upland forests in northern New England, USA: implications of climate change

    Science.gov (United States)

    Richardson, J. B.; Friedland, A. J.

    2015-11-01

    Climatic changes in the northeastern US are expected to cause coniferous stands to transition to deciduous stands over the next hundred years. Mercury (Hg) sequestration in forest soils may change as a result. In order to understand potential effects of such a transition, we studied aboveground vegetation and soils at paired coniferous and deciduous stands on eight mountains in Vermont and New Hampshire, USA. Organic horizons at coniferous stands accumulated more total Hg (THg; 42 ± 6 g ha-1) than deciduous stands (30 ± 4 g ha-1). Total Hg pools in the mineral horizons were similar for coniferous (46 ± 8 g ha-1) and deciduous stands (45 ± 7 g ha-1). Soil properties (C, % clay, and pH) explained 56 % of the variation in mineral soil Hg concentration when multiply regressed. Foliar and bole wood Hg concentrations were generally greater for coniferous species than deciduous species. Using allometric equations, we estimated that aboveground accumulation of Hg in foliage and woody biomass was similar between vegetation types but that coniferous stands have significantly smaller annual litterfall fluxes (0.03 g ha-1 yr-1) than deciduous stands (0.24 g ha-1 yr-1). We conclude that organic horizon Hg accumulation is influenced by vegetation type but mineral horizon Hg accumulation is primarily controlled by soil properties. Further investigations into the effect of vegetation type on volatilization, atmospheric deposition, and leaching rates are needed to constrain regional Hg cycling rates.

  12. Plantation livelihoods in central Vietnam

    DEFF Research Database (Denmark)

    Thulstrup, Andreas Waaben

    2014-01-01

    Social vulnerability to disturbances is influenced by the economic and political context in which actors and institutions both enable and constrain household access to productive resources. These resources are crucial as a means for mitigating, coping, and responding to impacts of natural...... disturbances. The Vietnamese Government has formulated policies aimed at achieving dual objectives of socio-economic development and environmental protection through the expansion of plantation forests. Negative social impacts and worrying environmental trends have been noted by a number of scholars. However...

  13. Plantation forests and biodiversity: oxymoron or opportunity?

    Science.gov (United States)

    Eckehard G. Brockerhoff; Hervé Jactel; John A. Parrotta; Christopher Quine; Jeffrey Sayer

    2008-01-01

    Losses of natural and semi-natural forests, mostly to agriculture, are a significant concern for biodiversity. Against this trend, the area of intensively managed plantation forests increases, and there is much debate about the implications for biodiversity. We provide a comprehensive review of the function of plantation forests as habitat compared with other land...

  14. Plantation forests, climate change and biodiversity

    Science.gov (United States)

    S.M. Pawson; A. Brin; E.G. Brockerhoff; D. Lamb; T.W. Payn; A. Paquette; J.A. Parrotta

    2013-01-01

    Nearly 4 % of the world’s forests are plantations, established to provide a variety of ecosystem services, principally timber and other wood products. In addition to such services, plantation forests provide direct and indirect benefits to biodiversity via the provision of forest habitat for a wide range of species, and by reducing negative impacts on natural forests...

  15. EXOTIC PLANTATIONS IN BELETE FOREST[1

    African Journals Online (AJOL)

    User

    Abstract. The potential for regeneration of native woody species in exotic plantation stands and in the adjacent natural forest in Belete forest was studied. The objective of the study was to assess the diversity and density of the naturally regenerated woody species in plantations at Belete forest. Vegetation assessment within ...

  16. Plantation agriculture in the tropics - environmental issues

    NARCIS (Netherlands)

    Hartemink, A.E.

    2005-01-01

    Plantation agriculture is more than 400 years old and contributes to the regional and national economies in many tropical countries. This paper reviews some of the main environmental issues related to plantation agriculture with perennial crops, including soil erosion, soil fertility decline,

  17. An exhaustive inventory of coniferous trees in an agricultural landscape.

    Science.gov (United States)

    Rousselet, Jérôme; Roques, Alain; Garcia, Jacques; Rossi, Jean-Pierre

    2015-01-01

    Various species of forest trees are commonly used for ornamental purposes and are therefore frequently found in non-forest ecosystems. These trees constitute a significant component of the trees outside forests (TOF). Although increasingly recognized as prominent feature of agricultural lands and built-up areas, not much is known, however, about TOF since they are generally absent from forest inventories. In the present study, we focus on the coniferous tree species that constitute potential hosts for a forest defoliator, the pine processionary moth Thaumetopoeapityocampa Den. & Schiff. (Lepidoptera, Notodontidae). We carried out an exhaustive inventory of all pines (Pinus spp.), cedars (Cedrus spp.) and Douglas-fir (Pseudotsugamenziesii) in a 22 × 22 km study window located in the open-field region of Beauce in the centre of France. We recorded a total of 3834 individuals or small groups host trees corresponding a density of 7.9 occurrences per 100 ha. We provide the spatial coordinates of the points without differentiation between tree species.

  18. Phenology of plants in relation to ambient environment in a subalpine forest of Uttarakhand, western Himalaya.

    Science.gov (United States)

    Bisht, Vinod K; Kuniyal, Chandra P; Bhandari, Arvind K; Nautiyal, Bhagwati P; Prasad, P

    2014-07-01

    Observations on phenology of some representative trees, shrubs, under-shrubs and herbs in a subalpine forest of Uttarakhand, western Himalaya were recorded. With the commencement of favorable growth season in April, occurrence of leaf fall was indicatory growth phenomenon in Quercus semecarpifolia, Q. floribunda and Abies spectabilis. However, active vegetative growth in herbaceous species starts onward April and fruit maturation and seed dehiscence are completed from mid of September to October. In general, vegetative growth and reproductive stages in majority of the studied species seems to be dependent on adequate moisture content and also flowering and fruiting in subalpine plants correlate ambient temperature.

  19. Thinning effect on photosynthesis depends on needle ages in a Chinese fir (Cunninghamia lanceolata) plantation.

    Science.gov (United States)

    Li, Ren-Shan; Yang, Qing-Peng; Zhang, Wei-Dong; Zheng, Wen-Hui; Chi, Yong-Gang; Xu, Ming; Fang, Yun-Ting; Gessler, Arthur; Li, Mai-He; Wang, Si-Long

    2017-02-15

    Canopies in evergreen coniferous plantations often consist of various-aged needles. However, the effect of needle age on the photosynthetic responses to thinning remains ambiguous. Photosynthetic responses of different-aged needles to thinning were investigated in a Chinese fir (Cunninghamia lanceolata) plantation. A dual isotope approach [simultaneous measurements of stable carbon (δ(13)C) and oxygen (δ(18)O) isotopes] was employed to distinguish between biochemical and stomatal limitations to photosynthesis. Our results showed that increases in net photosynthesis rates upon thinning only occurred in the current-year and one-year-old needles, and not in the two- to four-year-old needles. The increased δ(13)C and declined δ(18)O in current year needles of trees from thinned stands indicated that both the photosynthetic capacity and stomatal conductance resulted in increasing photosynthesis. In one-year-old needles of trees from thinned stands, an increased needle δ(13)C and a constant needle δ(18)O were observed, indicating the photosynthetic capacity rather than stomatal conductance contributed to the increasing photosynthesis. The higher water-soluble nitrogen content in current-year and one-year-old needles in thinned trees also supported that the photosynthetic capacity plays an important role in the enhancement of photosynthesis. In contrast, the δ(13)C, δ(18)O and water-soluble nitrogen in the two- to four-year-old needles were not significantly different between the control and thinned trees. Thus, the thinning effect on photosynthesis depends on needle age in a Chinese fir plantation. Our results highlight that the different responses of different-aged needles to thinning have to be taken into account for understanding and modelling ecosystem responses to management, especially under the expected environmental changes in future. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Fuel plantation research. Progress report

    Energy Technology Data Exchange (ETDEWEB)

    Stubbs, J.

    1977-08-01

    Research in chemical induction of lightwood is summarized. Four large-scale proof of concept studies have been installed that test five paraquat treatments on a total of 71,228 trees. This wood will be used in actual pulp mill and extraction plant runs to determine oleoresin recovery and possible processing problems. Nearly 3,000 wood samples have been collected to ascertain duration of treatment effects. Results of complementary studies are also reported; most of these are concerned with optimization of paraquat application techniques and the effect of species differences on these methods. A large study was installed to field screen selected insecticides for insect pest control in lightwood operations, and interim results are presented. Dowco 214 (Reldon) proved to be an adequate substitute for BHC and 0.5% concentrations were as effective as 1%. Ten northern and seven western conifer species were tested for their reaction to paraquat treatment. All members of genus Pinus showed appreciable resin soaking but other coniferous genera did not. Feasibility of oleoresin substitution for petrochemicals was investigated.

  1. Ecological Impact on Nitrogen and Phosphorus Cycling of a Widespread Fast-growing Leguminous Tropical Forest Plantation Tree Species, Acacia mangium

    Directory of Open Access Journals (Sweden)

    Shigehiro Ishizuka

    2011-11-01

    Full Text Available Symbiotic nitrogen fixation is one of the major pathways of N input to forest ecosystems, enriching N availability, particularly in lowland tropics. Recently there is growing concern regarding the wide areas of fast-growing leguminous plantations that could alter global N2O emissions. Here, we highlight substantially different N and phosphorus utilization and cycling at a plantation of Acacia mangium, which is N2-fixing and one of the major plantation species in tropical/subtropical Asia. The litterfall, fresh leaf quality and fine-root ingrowth of A. mangium were compared to those of non-N2-fixing Swietenia macrophylla and coniferous Araucaria cunninghamii in wet tropical climates in Borneo, Malaysia. The N and P concentrations of the A. mangium fresh leaves were higher than those of the other two species, whereas the P concentration in the leaf-litterfall of A. mangium was less than half that of the others; in contrast the N concentration was higher. The N:P ratio in the A. mangium leaf was markedly increased from fresh-leaf (29 to leaf-litterfall (81. Although the N flux in the total litterfall at the A. mangium plantation was large, the fine-root ingrowth of A. mangium significantly increased by applying both N and P. In conclusion, large quantities of N were accumulated and returned to the forest floor in A. mangium plantation, while its P resorption capacity was efficient. Such large N cycling and restricted P cycling in wide areas of monoculture A. mangium plantations may alter N and P cycling and their balance in the organic layer and soil on a stand level.

  2. Atmospheric deposition in coniferous and deciduous tree stands in Poland

    Science.gov (United States)

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

    2016-05-01

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

  3. Ecosystem-based greenhouse budgets in oil palm plantations differ with plantation age

    Science.gov (United States)

    Meijide, Ana; Hassler, Evelyn; Corre, Marife D.; June, Tania; Veldkamp, Edzo; Knohl, Alexander

    2016-04-01

    Global increase in demand of palm oil is leading to the expansion of oil palm plantations, particularly in SE Asia. Oil palm plantations in Sumatra, Indonesia, together with those in Kalimantan, are responsible for half of the world's palm oil production. Available studies point to plantations being large carbon dioxide (CO2) sinks due to the high photosynthetic rates of oil palm as a result of high fertilizer inputs, especially in large-scale plantations. However, methane (CH4) uptake in the soil of oil palm plantations is reduced and soil nitrous oxide (N2O) emissions increased right after nitrogen (N) fertilization. Greenhouse gas (GHG) budgets at the ecosystem level are still missing, and the few available information was derived from mature plantations, pointing to a lack of knowledge on the changes of these GHG budgets with plantation age. With the aim of quantifying CO2, CH4 and N2O fluxes during the non-productive and productive phases of oil palm cultivation, an eddy covariance (EC) tower was installed in a 2-year old (non-productive) oil palm plantation and was subsequently moved to a 12-year old (productive) plantation. Both sites were on Acrisol soils and were located in Jambi province, Sumatra. Chamber-based measurements of soil GHG fluxes were also carried out along the EC footprint. Net ecosystem exchange (NEE), based on EC measurement, showed that the non-productive plantation was a strong CO2 source (990 g C m-2 yr-1) whereas the productive plantation was a CO2 sink (-790 g C m-2 yr-1). For CH4 fluxes, both plantations showed similar soil CH4 uptake that led to a small carbon sink of (~1.3 g C m-2 yr-1). Soil N2O fluxes were high in the productive plantation (3.26 ± 1.73 kg N ha-1 yr-1), as measurements were carried out in a plantation with high fertilization rates. In the non-productive plantation, soil N2O fluxes were lower and were associated with fertilization events. Our results show that the global warming potential of a non-productive oil

  4. Linkages between grazing history and herbivore exclusion on decomposition rates in mineral soils of subalpine grasslands

    Science.gov (United States)

    Alan G. Haynes; Martin Schutz; Nina Buchmann; Deborah S. Page-Dumroese; Matt D. Busse; Anita C. Risch

    2014-01-01

    Herbivore-driven changes to soil properties can influence the decomposition rate of organic material and therefore soil carbon cycling within grassland ecosystems. We investigated how aboveground foraging mammalian and invertebrate herbivores affect mineral soil decomposition rates and associated soil properties in two subalpine vegetation types (shortgrass and tall-...

  5. Human disturbance provides foraging opportunities for birds in primary subalpine forest

    DEFF Research Database (Denmark)

    DuBay, Shane G.; Hart Reeve, Andrew; Wu, Yongjie

    2017-01-01

    to species that naturally occur in edge, open, or disturbed habitats. With observations and experiments we provide evidence of insectivorous birds exploiting human disturbance in primary subalpine forest in the mountains of southern China, displaying behavioral flexibility to gain novel foraging...

  6. Net primary productivity of subalpine meadows in Yosemite National Park in relation to climate variability

    Science.gov (United States)

    Peggy E. Moore; Jan W. van Wagtendonk; Julie L. Yee; Mitchel P. McClaran; David N. Cole; Neil K. McDougald; Matthew L. Brooks

    2013-01-01

    Subalpine meadows are some of the most ecologically important components of mountain landscapes, and primary productivity is important to the maintenance of meadow functions. Understanding how changes in primary productivity are associated with variability in moisture and temperature will become increasingly important with current and anticipated changes in climate....

  7. Drought-driven disturbance history characterizes a southern Rocky Mountain subalpine forest

    Science.gov (United States)

    R. Justin DeRose; James N. Long

    2012-01-01

    The view that subalpine forest vegetation dynamics in western North America are "driven" by a particular disturbance type (i.e., fire) has shaped our understanding of their disturbance regimes. In the wake of a recent (1990s) landscape- extent spruce beetle (Dendroctonus rufipennis Kirby) outbreak in the southern Rocky Mountains, we re-examined the temporal...

  8. Water use patterns of three species in subalpine forest, Southwest China: the deuterium isotope approach

    Science.gov (United States)

    Qing Xu; Harbin Li; Jiquan Chen; Jiquan Cheng; Xiaoli Cheng; Shirong Liu; Shuqing An

    2011-01-01

    Determination of water sources of plant species in a community is critical for understanding the hydrological processes and their importance in ecosystem functions. Such partitioning of plant xylem water into specific sources (i.e. precipitation, groundwater) can be achieved by analyzing deuterium isotopic composition (δD) values for source waters. A subalpine dark...

  9. Comparison of the abundance and composition of litter fauna in tropical and subalpine forests

    Science.gov (United States)

    G. Gonzalez; T.R. Seastedt

    2000-01-01

    In this study, we quantify the abundance and composition of the litter fauna in dry and wet tropical forests and north- and south-facing subalpine forests. We used the same litter species contained in litterbags across study sites to standardize for substrate conditions, and a single method of fauna extraction from the litter (Tullgren method). Fauna densities were...

  10. Human-Related Forest Fires in the Subalpine Belt of the Spanish Pyrenees

    Science.gov (United States)

    Sanjuán, Yasmina; María García-Ruiz, José; Beguería, Santiago; Serrano-Muela, María Pilar; González-Sampériz, Penélope; Valero-Garcés, Blas; Arnáez, José

    2014-05-01

    The subalpine belt of the Central Pyrenees ranges approximately between 1700 and 2200 m a.s.l. This area should be covered with dense forests of Pinus sylvestris and P. uncinata, with increasingly open formations towards the upper forest limit. At present, most of the subalpine belt is occupied with grasslands due to human-induced deforestation for enlarging the area occupied by summer pastures. Two are the most important scientific problems related to deforestation of the subalpine belt: (i) the timing of deforestation, and (ii) the geomorphic consequences of a sudden substitution of forests by grasslands. Up to now, intense deforestation is clearly recorded in regional palaeoenvironmental sequences since the Middle Ages and, traditionally, this practice was usually attributed to large fires with the purpose of balance the winter and summer pasture resources. Nevertheless, the presence of abundant remnants of prehistoric monuments (dolmens, cromlechs, tumulus) in the subalpine belt induced to think in a previous seasonal presence of human populations, most probably practicing some primitive type of transhumance. This would only be possible if part of the subalpine forests would be burnt to allow a limited expansion of grasslands, despite the consequences in the landscape of this kind of practices were not permanent in time. We present here new dates of fire occurrence from charcoal obtained from soils in the hillslopes and from lacustrine sediments. Two periods of human-induced fires have been identified: (i) between 2500 and 2000 cal. yr BP, and (ii) between 1100 and 900 cal yr BP. The consequences of deforestation can be easily observed in the landscape, particularly shallow landslide activity, gelifluction, solifluction and the rapid development of parallel incisions in the steepest slopes.

  11. Manipulation of subalpine and alpine microclimate in the Alpine Treeline Warming Experiment

    Science.gov (United States)

    Kueppers, L. M.; Moyes, A. B.; Ferrenberg, S. M.; Christianson, D. S.; Castanha, C.; Germino, M. J.

    2011-12-01

    To experimentally test model projections of subalpine tree species' uphill migration with climate change, we have established the Alpine Treeline Warming Experiment at Niwot Ridge, CO. Common gardens subject to full factorial warming and watering experiments are replicated across three sites: near the lower limit of subalpine forest, within the alpine-treeline ecotone, and in the alpine tundra, beyond the current elevation ranges of the species. In 2010, differences in ambient climate among the three sites included 5.1° C greater growing-season air temperature and 0.5 kPa greater vapor pressure deficit in the lowest compared to the upper two sites. The lower subalpine site also experienced lower soil moisture compared to the upper two sites. Snowmelt date varied substantially between sites, with the longest snow-free period in the lower subalpine site and the shortest in the treeline site. In all sites, we observed advances in the timing of snowmelt in heated relative to control plots. The warming treatment also raised 5 cm soil temperatures by 3° C at the lower subalpine site, and by 1° C in the upper two sites, averaged over the growing season. More substantial wind in the alpine diminished the heating effect through sensible heat loss. Seasonal average volumetric soil moisture at 5-10 cm did not vary strongly among treatments even though seedling survival and gas exchange data suggest that water additions alleviated drought stress in some plots. These preliminary findings for identical warming and watering treatments across our three high mountain sites suggest that microclimate responses vary with radiation environment, patterns of snow accumulation, and wind speed. Some of these differences are realistic for a future warmer world, while others are artifacts of the experimental approach. Microclimate differences in 2011 reflect modified heating methods and a different spring hydroclimate (later snow accumulation and melt), highlighting the importance of

  12. A Comparison of Infrared Gas Analyzers Above a Subalpine Forest

    Science.gov (United States)

    Burns, S. P.; Metzger, S.; Blanken, P.; Burba, G. G.; Swiatek, E.; Li, J.; Conrad, B.

    2014-12-01

    Infrared gas analyzers (IRGAs) are a key component in theeddy-covariance measurement of water vapor and carbon dioxide exchangebetween the surface and atmosphere. Historically, closed-path IRGAshave been used for the fast (> 10 Hz) measurement of atmospheric H2Oand CO2. In order to use them in the field, these IRGAs were typicallyhoused in temperature-controlled enclosures or buildings that weretens of meters away from the measurement location. This necessitatedthe use of long tubing and pumps to bring the air sample to the IRGAcell. Attenuation of H2O and CO2 fluctuations within the tubing was apersistent problem with such a setup, especially for H2O. As analternative, open-path IRGAs have frequently been utilized, but thekey trade-offs with the open-path design are: (i) precipitation anddew-related data gaps, and (ii) the need to account for WPL densityeffects. Over the past five years a new type of closed-path IRGA hasemerged which is weather-proof, compact, and low-maintenance. Becauseof its small size, short intake tubing can be used, which places thesampling cell close to the sonic anemometer and reduces high frequencysignal loss. Two such IRGAs are the LI-COR LI-7200 and the CampbellScientific EC155, which is part of the CPEC200 eddy covariance system.The Niwot Ridge AmeriFlux tower has used a LI-COR LI-6262 IRGA tomeasure CO2 fluxes above a subalpine forest since November, 1998.Starting in summer 2013, a LI-7200 (along with an open-path LI-7500)were deployed at 21.5 m on the AmeriFlux tower. In Fall 2013, aEC155/CPEC200 was added so that a side-by-side comparison between allfour IRGAs was possible. The preliminary results presented in ourstudy compare the CO2 and H2O mean and variance measured by each IRGA,the vertical wind statistics from three side-by-side sonicanemometers, as well as the corresponding spectra and cospectra fromthese sensors as well as other important aspects of systemperformance.

  13. Holocene vegetation and fire regimes in subalpine and mixed conifer forests, southern Rocky Mountains, USA

    Science.gov (United States)

    Anderson, R. Scott; Allen, Craig D.; Toney, J.L.; Jass, R.B.; Bair, A.N.

    2008-01-01

    Our understanding of the present forest structure of western North America hinges on our ability to determine antecedent forest conditions. Sedimentary records from lakes and bogs in the southern Rocky Mountains of Colorado and New Mexico provide information on the relationships between climate and vegetation change, and fire history since deglaciation. We present a new pollen record from Hunters Lake (Colorado) as an example of a high-elevation vegetation history from the southern Rockies. We then present a series of six sedimentary records from ???2600 to 3500-m elevation, including sites presently at the alpine?subalpine boundary, within the Picea engelmannii?Abies lasiocarpa forest and within the mixed conifer forest, to determine the history of fire in high-elevation forests there. High Artemisia and low but increasing percentages of Picea and Pinus suggest vegetation prior to 13 500 calendar years before present (cal yr BP) was tundra or steppe, with open spruce woodland to ???11 900 cal yr BP. Subalpine forest (Picea engelmannii, Abies lasiocarpa) existed around the lake for the remainder of the Holocene. At lower elevations, Pinus ponderosa and/or contorta expanded 11 900 to 10 200 cal yr BP; mixed conifer forest expanded ???8600 to 4700 cal yr BP; and Pinus edulis expanded after ???4700 cal yr BP. Sediments from lake sites near the alpine?subalpine transition contained five times less charcoal than those entirely within subalpine forests, and 40 times less than bog sites within mixed conifer forest. Higher fire episode frequencies occurred between ???12 000 and 9000 cal yr BP (associated with the initiation or expansion of south-west monsoon and abundant lightning, and significant biomass during vegetation turnover) and at ???2000?1000 cal yr BP (related to periodic droughts during the long-term trend towards wetter conditions and greater biomass). Fire episode frequencies for subalpine?alpine transition and subalpine sites were on average 5 to 10 fire

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

    Science.gov (United States)

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

    2015-01-01

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

  15. Modelling carbon dynamics in coniferous forest soils in a temperature gradient.

    NARCIS (Netherlands)

    Hyvonen, R.; Berg, M.P.; Agren, G.I.

    2002-01-01

    Climate change and changes in land use will alter the stores of carbon and turnover of soil organic matter. We have used a theory for carbon cycles in terrestrial ecosystems to analyse changes in soil organic matter turnover in coniferous forests. The central concepts of the theory are a

  16. Absorption of Power Plants СО2 Emissions by Coniferous Tree Stands

    Directory of Open Access Journals (Sweden)

    Suvorova G.G.

    2015-12-01

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

  17. Chemical ecology and management of bark beetles in western coniferous forests

    Science.gov (United States)

    Christopher J. Fettig

    2013-01-01

    The future looks bright for the development and use of semiochemical-based tools in forests, particularly in remote and sensitive areas where other management techniques (e.g., the use of insecticides) may not be appropriate. This editorial provides an concise overview of chemical ecology and management of bark beetles in western coniferous forests.

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

    NARCIS (Netherlands)

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

    2000-01-01

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

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

    NARCIS (Netherlands)

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

    2000-01-01

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

  20. Minimizing measurement uncertainties of coniferous needle-leaf optical properties, part I: methodological review

    NARCIS (Netherlands)

    Yanez Rausell, L.; Schaepman, M.E.; Clevers, J.G.P.W.; Malenovsky, Z.

    2014-01-01

    Optical properties (OPs) of non-flat narrow plant leaves, i.e., coniferous needles, are extensively used by the remote sensing community, in particular for calibration and validation of radiative transfer models at leaf and canopy level. Optical measurements of such small living elements are,

  1. Coniferous needle-leaves, shots and canopies : a remote sensing approach

    NARCIS (Netherlands)

    Yanez Rausell, L.

    2014-01-01

    Coniferous forests are important in the regulation of the Earth’s climate and thus continuous monitoring of these ecosystems is crucial to better understand potential responses to climate change. Optical remote sensing (RS) provides powerful methods for the estimation of essential climate

  2. Measurement of the dry deposition flux of NH3 on to coniferous forest

    NARCIS (Netherlands)

    Duyzer, J.H.; Verhagen, H.L.M.; Weststrate, J.H.; Bosveld, F.C.

    1992-01-01

    The dry deposition flux of NH3 to coniferous forest was determined by the micrometeorological gradient method using a 36m high tower. Aerodynamic characteristics of the site were studied, using a second tower erected in the forest 100m from the first. Fluxes and gradients of heat and momentum

  3. Variation in winter snowpack depth and duration influences summer soil respiration in a subalpine meadow

    Science.gov (United States)

    Arnold, C. L.; Ghezzehei, T. A.; Berhe, A. A.

    2012-12-01

    Subalpine meadows in the Sierra Nevada rely on the depth and duration of the winter snowpack to supply ample water to restore the water table in the meadow during the spring snowmelt. This study examines the role that interannual variability in the winter snowpack plays in the overall rate of summer soil respiration along a hydrologic gradient in a subalpine meadow. Carbon dioxide efflux from the meadow was measured from June through September in 2011 and 2012 using soil collars and a LICOR 8100A infrared gas analyzer. Preliminary results show that soil respiration rates are influenced by the hydrologic gradient across the meadow, with drier regions peaking earlier in the summer as compared to wetter regions. We also show that high snowpack years can suppress soil respiration in the meadow until late in the summer season as compared to low snowpack years, where soil respiration peaks early in the summer.

  4. Phenology of plants in relation to ambient environment in a subalpine forest of Uttarakhand, western Himalaya

    OpenAIRE

    Bisht, Vinod K.; Kuniyal, Chandra P.; Bhandari, Arvind K.; Nautiyal, Bhagwati P.; Prasad, P.

    2014-01-01

    Observations on phenology of some representative trees, shrubs, under-shrubs and herbs in a subalpine forest of Uttarakhand, western Himalaya were recorded. With the commencement of favorable growth season in April, occurrence of leaf fall was indicatory growth phenomenon in Quercus semecarpifolia, Q. floribunda and Abies spectabilis. However, active vegetative growth in herbaceous species starts onward April and fruit maturation and seed dehiscence are completed from mid of September to Octo...

  5. Bleaching of leaf litter and associated microfungi in subboreal and subalpine forests.

    Science.gov (United States)

    Hagiwara, Yusuke; Matsuoka, Shunsuke; Hobara, Satoru; Mori, Akira S; Hirose, Dai; Osono, Takashi

    2015-10-01

    Fungal decomposition of lignin leads to the whitening, or bleaching, of leaf litter, especially in temperate and tropical forests, but less is known about such bleaching in forests of cooler regions, such as boreal and subalpine forests. The purposes of the present study were to examine the extent of bleached area on the surface of leaf litter and its variation with environmental conditions in subboreal and subalpine forests in Japan and to examine the microfungi associated with the bleaching of leaf litter by isolating fungi from the bleached portions of the litter. Bleached area accounted for 21.7%-32.7% and 2.0%-10.0% of total leaf area of Quercus crispula and Betula ermanii, respectively, in subboreal forests, and for 6.3% and 18.6% of total leaf area of B. ermanii and Picea jezoensis var. hondoensis, respectively, in a subalpine forest. In subboreal forests, elevation, C/N ratio and pH of the FH layer, and slope aspect were selected as predictor variables for the bleached leaf area. Leaf mass per area and lignin content were consistently lower in the bleached area than in the nonbleached area of the same leaves, indicating that the selective decomposition of acid unhydrolyzable residue (recalcitrant compounds such as lignin, tannins, and cutins) enhanced the mass loss of leaf tissues in the bleached portions. Isolates of a total of 11 fungal species (6 species of Ascomycota and 5 of Basidiomycota) exhibited leaf-litter-bleaching activity under pure culture conditions. Two fungal species (Coccomyces sp. and Mycena sp.) occurred in both subboreal and subalpine forests, which were separated from each other by approximately 1100 km.

  6. Modeling the effects of tree species and incubation temperature on soil's extracellular enzyme activity in 78-year-old tree plantations

    Science.gov (United States)

    Zhou, Xiaoqi; Wang, Shen S. J.; Chen, Chengrong

    2017-12-01

    Forest plantations have been widely used as an effective measure for increasing soil carbon (C), and nitrogen (N) stocks and soil enzyme activities play a key role in soil C and N losses during decomposition of soil organic matter. However, few studies have been carried out to elucidate the mechanisms behind the differences in soil C and N cycling by different tree species in response to climate warming. Here, we measured the responses of soil's extracellular enzyme activity (EEA) to a gradient of temperatures using incubation methods in 78-year-old forest plantations with different tree species. Based on a soil enzyme kinetics model, we established a new statistical model to investigate the effects of temperature and tree species on soil EEA. In addition, we established a tree species-enzyme-C/N model to investigate how temperature and tree species influence soil C/N contents over time without considering plant C inputs. These extracellular enzymes included C acquisition enzymes (β-glucosidase, BG), N acquisition enzymes (N-acetylglucosaminidase, NAG; leucine aminopeptidase, LAP) and phosphorus acquisition enzymes (acid phosphatases). The results showed that incubation temperature and tree species significantly influenced all soil EEA and Eucalyptus had 1.01-2.86 times higher soil EEA than coniferous tree species. Modeling showed that Eucalyptus had larger soil C losses but had 0.99-2.38 times longer soil C residence time than the coniferous tree species over time. The differences in the residual soil C and N contents between Eucalyptus and coniferous tree species, as well as between slash pine (Pinus elliottii Engelm. var. elliottii) and hoop pine (Araucaria cunninghamii Ait.), increase with time. On the other hand, the modeling results help explain why exotic slash pine can grow faster, as it has 1.22-1.38 times longer residual soil N residence time for LAP, which mediate soil N cycling in the long term, than native coniferous tree species like hoop pine and

  7. Modeling the effects of tree species and incubation temperature on soil's extracellular enzyme activity in 78-year-old tree plantations

    Directory of Open Access Journals (Sweden)

    X. Zhou

    2017-12-01

    Full Text Available Forest plantations have been widely used as an effective measure for increasing soil carbon (C, and nitrogen (N stocks and soil enzyme activities play a key role in soil C and N losses during decomposition of soil organic matter. However, few studies have been carried out to elucidate the mechanisms behind the differences in soil C and N cycling by different tree species in response to climate warming. Here, we measured the responses of soil's extracellular enzyme activity (EEA to a gradient of temperatures using incubation methods in 78-year-old forest plantations with different tree species. Based on a soil enzyme kinetics model, we established a new statistical model to investigate the effects of temperature and tree species on soil EEA. In addition, we established a tree species–enzyme–C∕N model to investigate how temperature and tree species influence soil C∕N contents over time without considering plant C inputs. These extracellular enzymes included C acquisition enzymes (β-glucosidase, BG, N acquisition enzymes (N-acetylglucosaminidase, NAG; leucine aminopeptidase, LAP and phosphorus acquisition enzymes (acid phosphatases. The results showed that incubation temperature and tree species significantly influenced all soil EEA and Eucalyptus had 1.01–2.86 times higher soil EEA than coniferous tree species. Modeling showed that Eucalyptus had larger soil C losses but had 0.99–2.38 times longer soil C residence time than the coniferous tree species over time. The differences in the residual soil C and N contents between Eucalyptus and coniferous tree species, as well as between slash pine (Pinus elliottii Engelm. var. elliottii and hoop pine (Araucaria cunninghamii Ait., increase with time. On the other hand, the modeling results help explain why exotic slash pine can grow faster, as it has 1.22–1.38 times longer residual soil N residence time for LAP, which mediate soil N cycling in the long term, than native

  8. Impacts of smallholder tree plantation in Amhara Region of Ethiopia ...

    African Journals Online (AJOL)

    Impacts of smallholder tree plantation in Amhara Region of Ethiopia: the case of Lay Gayint and Fagta Locuma Districts. ... market access and linkages, value addition of plantation products, expansion of infrastructures especially road and telecommunication networks in the rural parts to raise participation in plantation.

  9. Designing and establishing a fine hardwood timber plantation

    Science.gov (United States)

    James R. McKenna; Lenny D. Farlee

    2013-01-01

    Today, new tools and lessons learned from established plantations of black walnut and other fine hardwoods can provide landowners with guidelines to design and establish successful plantations to produce quality timber for the future. From earlier plantations now maturing, we can recognize design features critical during establishment. Current production practices...

  10. Weed Control Trials in Cottonwood Plantations

    Science.gov (United States)

    R. M. Krinard

    1964-01-01

    Weed control in the first year is essential for establishing a cottonwood plantation, for the young trees can neither survive nor grow well if they must compete with other plants. Once the light and moisture conditions are established in its favor, cottonwood becomes the fastest growing tree in the South.

  11. Weed Control in Black Walnut Plantations

    Science.gov (United States)

    Calvin F. Bey; Robert D. Williams

    1976-01-01

    Weeds must be controlled for at least 3 years to successfully establish walnut plantations. Whether by cultivating or applying chemicals, a strip or spot 4 feet wide is sufficient the first 2 years, followed by a 6-foot spot or strip for the third and fourth years.

  12. Soil Compaction Absent in Plantation Thinning

    Science.gov (United States)

    Tony King; Sharon Haines

    1979-01-01

    We examine the effects on soil bulk density by using a TH-105 Thinner Harvester and two forwarders in a mechanically thinned slash pine (Pinus elliottii Engelm.) plantation. Points in the machine tracks were sampled before and after harvesting at depths of 5 and 10 cm (2 and 4 in) for moisture and bulk density. Both the standard gravimetric method...

  13. In vitro fungistatic effects of natural coniferous resin from Norway spruce (Picea abies).

    Science.gov (United States)

    Rautio, M; Sipponen, A; Lohi, J; Lounatmaa, K; Koukila-Kähkölä, P; Laitinen, K

    2012-08-01

    Resins (rosin, pitch) are natural products of the coniferous trees and are antimicrobial against a wide range of microbes. The antifungal effectiveness of resin, purified from Norway spruce (Picea abies), was studied against human pathogenic fungi and yeasts with the agar plate diffusion tests and electron microscopy (EM). The fungistatic effect of these resin mixtures (resin salves) was tested against a set of Candida yeasts, dermatophytes, and opportunistic fungi. Transmission and scanning EM was done from samples of fungi (Trichophyton mentagrophytes). In agar diffusion tests, the resin was strongly antifungal against all dermatophytes tested, e.g., against all fungi of the genus Trichophyton, but it was not antifungal against the Candida yeasts or against the opportunistic fungi tested. According to EM, resin caused damages in the cell hyphae and cell wall structures. We conclude that, in the agar plate diffusion test, coniferous resins are strongly fungistatic against the dermatophytic fungi only.

  14. Measurement of the dry deposition flux of NH3 on to coniferous forest

    OpenAIRE

    Duyzer, J.H.; Verhagen, H.L.M.; Weststrate, J.H.; Bosveld, F.C.

    1992-01-01

    The dry deposition flux of NH3 to coniferous forest was determined by the micrometeorological gradient method using a 36m high tower. Aerodynamic characteristics of the site were studied, using a second tower erected in the forest 100m from the first. Fluxes and gradients of heat and momentum measured on both towers indicated a fairly homogeneous turbulent flow field over the studied area of the forest. Site specific flux profile functions for heat were derived from continuous measurements of...

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

    OpenAIRE

    Jeanne Portier; Sylvie Gauthier; Alain Leduc; Dominique Arseneault; Yves Bergeron

    2016-01-01

    Fire is the main disturbance in North American coniferous boreal forests. In Northern Quebec, Canada, where forest management is not allowed, the landscape is gradually constituted of more opened lichen woodlands. Those forests are discontinuous and show a low regeneration potential resulting from the cumulative effects of harsh climatic conditions and very short fire intervals. In a climate change context, and because the forest industry is interested in opening new territories to forest man...

  16. Nanocarbon materials obtained of coniferous trees in the composition of black powder

    Directory of Open Access Journals (Sweden)

    Zulkhair Mansurov

    2012-03-01

    Full Text Available Obtained black powders from coniferous wood. The carbon content of up to 90% can be used in warfare, pyrotechnics and industries. In the Republic of Kazakhstan does not produce gunpowder. In the energy-intensive materials laboratory, developed industrial black powders (ordinary, composed of components produced in the republic of Kazakhstan. Sulfur, activated carbon, based on apricot seeds and rice husks, softwood sawdust, which have lower costs than their foreign counterparts.

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

    Science.gov (United States)

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

    2017-12-01

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

  18. Soil microbial community structure and diversity are largely influenced by soil pH and nutrient quality in 78-year-old tree plantations

    Science.gov (United States)

    Zhou, Xiaoqi; Guo, Zhiying; Chen, Chengrong; Jia, Zhongjun

    2017-04-01

    Forest plantations have been recognised as a key strategy management tool for stocking carbon (C) in soils, thereby contributing to climate warming mitigation. However, long-term ecological consequences of anthropogenic forest plantations on the community structure and diversity of soil microorganisms and the underlying mechanisms in determining these patterns are poorly understood. In this study, we selected 78-year-old tree plantations that included three coniferous tree species (i.e. slash pine, hoop pine and kauri pine) and a eucalypt species in subtropical Australia. We investigated the patterns of community structure, and the diversity of soil bacteria and eukaryotes by using high-throughput sequencing of 16S rRNA and 18S rRNA genes. We also measured the potential methane oxidation capacity under different tree species. The results showed that slash pine and Eucalyptus significantly increased the dominant taxa of bacterial Acidobacteria and the dominant taxa of eukaryotic Ascomycota, and formed clusters of soil bacterial and eukaryotic communities, which were clearly different from the clusters under hoop pine and kauri pine. Soil pH and nutrient quality indicators such as C : nitrogen (N) and extractable organic C : extractable organic N were key factors in determining the patterns of soil bacterial and eukaryotic communities between the different tree species treatments. Slash pine and Eucalyptus had significantly lower soil bacterial and eukaryotic operational taxonomical unit numbers and lower diversity indices than kauri pine and hoop pine. A key factor limitation hypothesis was introduced, which gives a reasonable explanation for lower diversity indices under slash pine and Eucalyptus. In addition, slash pine and Eucalyptus had a higher soil methane oxidation capacity than the other tree species. These results suggest that significant changes in soil microbial communities may occur in response to chronic disturbance by tree plantations, and highlight

  19. Multi-functional energy plantation; Multifunktionella bioenergiodlingar

    Energy Technology Data Exchange (ETDEWEB)

    Boerjesson, Paal [Lund Univ. (Sweden). Environmental and Energy Systems Studies; Berndes, Goeran; Fredriksson, Fredrik [Chalmers Univ. of Technology, Goeteborg (Sweden). Dept. of Physical Resource Theory; Kaaberger, Tomas [Ecotraffic, Goeteborg (Sweden)

    2002-02-01

    There exists a significant potential for utilising perennial energy plantations in protecting and restoring polluted water and land resources in Sweden. By optimising the design, location and management, several additional environmental services could be obtained which will increase the value of the energy plantations, thereby improving future market conditions for biomass. Multi-functional energy plantations (mainly Salix but also energy grass) can be divided into two categories, those designed for dedicated environmental services (e.g. vegetation filters for wastewater and sewage sludge treatment and shelter belts against soil erosion), and those generating more general benefits (e.g. soil carbon accumulation, increased soil fertility, cadmium removal and increased hunting potential). The practical potential of those two categories is estimated to be equivalent to up to 3% and more than 20% of the total Swedish arable land, respectively. The regional conditions of utilising multi-functional plantations vary, however, with the best possibilities in densely populated areas dominated by farmland. The economic value of multi-functional plantations is normally highest for those designed for dedicated environmental services. Purification of wastewater has the highest value, which could exceed the production cost in conventional Salix plantations, followed by treatment of polluted drainage water in vegetation filters and buffer zones (equivalent to more than half of the production cost), recirculation of sewage sludge (around half of the production cost), erosion control (around one fourth) and increased hunting potential (up to 15% of the production cost). The value of increased hunting potential varies due to nearness to larger cities and in which part of Sweden the plantation is located. The economic value of cadmium removal and increased soil fertility is equivalent to a few percent of the production cost, but the value of cadmium removal might increase in the

  20. Warming and provenance limit tree recruitment across and beyond the elevation range of subalpine forest.

    Science.gov (United States)

    Kueppers, Lara M; Conlisk, Erin; Castanha, Cristina; Moyes, Andrew B; Germino, Matthew J; de Valpine, Perry; Torn, Margaret S; Mitton, Jeffry B

    2017-06-01

    Climate niche models project that subalpine forest ranges will extend upslope with climate warming. These projections assume that the climate suitable for adult trees will be adequate for forest regeneration, ignoring climate requirements for seedling recruitment, a potential demographic bottleneck. Moreover, local genetic adaptation is expected to facilitate range expansion, with tree populations at the upper forest edge providing the seed best adapted to the alpine. Here, we test these expectations using a novel combination of common gardens, seeded with two widely distributed subalpine conifers, and climate manipulations replicated at three elevations. Infrared heaters raised temperatures in heated plots, but raised temperatures more in the forest than at or above treeline because strong winds at high elevation reduced heating efficiency. Watering increased season-average soil moisture similarly across sites. Contrary to expectations, warming reduced Engelmann spruce recruitment at and above treeline, as well as in the forest. Warming reduced limber pine first-year recruitment in the forest, but had no net effect on fourth-year recruitment at any site. Watering during the snow-free season alleviated some negative effects of warming, indicating that warming exacerbated water limitations. Contrary to expectations of local adaptation, low-elevation seeds of both species initially recruited more strongly than high-elevation seeds across the elevation gradient, although the low-provenance advantage diminished by the fourth year for Engelmann spruce, likely due to small sample sizes. High- and low-elevation provenances responded similarly to warming across sites for Engelmann spruce, but differently for limber pine. In the context of increasing tree mortality, lower recruitment at all elevations with warming, combined with lower quality, high-provenance seed being most available for colonizing the alpine, portends range contraction for Engelmann spruce. The lower

  1. Warming and provenance limit tree recruitment across and beyond the elevation range of subalpine forest

    Science.gov (United States)

    Kueppers, Lara M.; Conlisk, Erin; Castanha, Cristina; Moyes, Andrew B.; Germino, Matthew; de Valpine, Perry; Torn, Margaret S.; Mitton, Jeffry B.

    2017-01-01

    Climate niche models project that subalpine forest ranges will extend upslope with climate warming. These projections assume that the climate suitable for adult trees will be adequate for forest regeneration, ignoring climate requirements for seedling recruitment, a potential demographic bottleneck. Moreover, local genetic adaptation is expected to facilitate range expansion, with tree populations at the upper forest edge providing the seed best adapted to the alpine. Here, we test these expectations using a novel combination of common gardens, seeded with two widely distributed subalpine conifers, and climate manipulations replicated at three elevations. Infrared heaters raised temperatures in heated plots, but raised temperatures more in the forest than at or above treeline because strong winds at high elevation reduced heating efficiency. Watering increased season-average soil moisture similarly across sites. Contrary to expectations, warming reduced Engelmann spruce recruitment at and above treeline, as well as in the forest. Warming reduced limber pine first-year recruitment in the forest, but had no net effect on fourth-year recruitment at any site. Watering during the snow-free season alleviated some negative effects of warming, indicating that warming exacerbated water limitations. Contrary to expectations of local adaptation, low-elevation seeds of both species initially recruited more strongly than high-elevation seeds across the elevation gradient, although the low-provenance advantage diminished by the fourth year for Engelmann spruce, likely due to small sample sizes. High- and low-elevation provenances responded similarly to warming across sites for Engelmann spruce, but differently for limber pine. In the context of increasing tree mortality, lower recruitment at all elevations with warming, combined with lower quality, high-provenance seed being most available for colonizing the alpine, portends range contraction for Engelmann spruce. The lower

  2. Vertical distribution of soil extractable organic C and N contents and total C and N stocks in 78-year-old tree plantations in subtropical Australia.

    Science.gov (United States)

    Zhou, Xiaoqi; Dong, Haibo; Lan, Zhongming; Bacon, Gary; Hao, Yanbin; Chen, Chengrong

    2017-08-11

    Few studies have focused on the effects of long-term forest plantations on the soil profile of carbon (C) and nitrogen (N) stocks. In this study, we selected 78-year-old tree plantations that included three coniferous tree species (i.e., slash pine, hoop pine and kauri pine) and a Eucalyptus species in subtropical Australia. We measured soil extractable organic C (EOC) and N (EON) contents and total C and N stocks under different tree species on the forest floor and along a soil profile to 100 cm depth. The results showed that Eucalyptus had significantly higher soil EOC contents (3.3 Mg ha(-1)) than the other tree species (EOC of 1.9-2.3 Mg ha(-1)) and had significantly higher EON (156 kg ha(-1)) contents than slash pine (107 kg ha(-1)). Eucalyptus had significantly higher soil C (58.9 Mg ha(-1)) and N (2.03 Mg ha(-1)) stocks than the other tree species (22.3-27.6 Mg C ha(-1) and 0.71-1.23 Mg N ha(-1)) at 0-100 cm depth. There were no differences in soil C stocks at the 0-100 cm depth among the coniferous tree species. Forest floor C stocks had stronger effects on mineral soil total N stocks than fine root biomass, whereas fine root biomass exerted stronger effects on soil total C stocks at the 0-100 cm depth than forest floor C and N stocks. Our results addressed large differences in soil C and N stocks under different tree species, which can provide useful information for local forest management practices in this region.

  3. Resurgence of human bothriocephalosis (Diphyllobothrium latum in the subalpine lake region

    Directory of Open Access Journals (Sweden)

    Renata BOUCHER-RODONI

    2001-02-01

    Full Text Available Human bothriocephalosis is once again being found in various catchment basins in the subalpine region, including Lago Maggiore and Lac Léman, which however are not isolated cases. Domestic animals are thought to be responsible for the survival of the parasite during the period when no human cases were reported. The new phenomenon of eating raw or poorly cooked fish is responsible for the resurgence of human bothriocephalosis, which affects various lake districts in Europe. This habit of eating raw fish might lead to the resurgence of a much more dangerous human parasitosis, transmitted in a similar way: infestation by Anisakis.

  4. Energy balance above a boreal coniferous forest: a difference in turbulent fluxes between snow-covered and snow-free canopies

    Science.gov (United States)

    Nakai, Yuichiro; Sakamoto, Tomoki; Terajima, Tomomi; Kitamura, Kenzo; Shirai, Tomoki

    1999-03-01

    To evaluate the interactive effects of snow and forest on turbulent fluxes between the forest surface and the atmosphere, the surface energy balance above a forest was measured by the eddy correlation method during the winter of 1995-1996. The forest was a young coniferous plantation comprised of spruce and fir. The study site, in Sapporo, northern Japan, had heavy and frequent snowfalls and the canopy was frequently covered with snow during the study period. A comparison of the observed energy balance above the forest for periods with and without a snow-covered canopy and an analysis using a single-source model gave the following results: during daytime when the canopy was covered with snow, the upward latent heat flux was large, about 80% of the net radiation, and the sensible heat flux was positive but small. On the other hand, during daytime when the canopy was dry and free from snow, the sensible heat flux was dominant and the latent heat flux was minor, about 10% of the net radiation. To explain this difference of energy partition between snow-covered and snow-free conditions, not only differences in temperature but also differences in the bulk transfer coefficients for latent heat flux were necessary in the model. Therefore, the high evaporation rate from the snow-covered canopy can be attributed largely to the high moisture availability of the canopy surface. Evaporation from the forest during a 60-day period in midwinter was estimated on a daily basis as net radiation minus sensible heat flux. The overall average evaporation during the 60-day period was 0·6 mm day-1, which is larger than that from open snow fields.

  5. The geographical distribution of plantation forests and land resources potentially available for pine plantations in the U.S. South

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Daowei [Forest Economics and Policy, School of Forestry and Wildlife Sciences, Auburn University, Auburn, Alabama 36849-5418 (United States); Polyakov, Maksym [Centre for Environmental Economics and Policy, University of Western Australia, M089, 35 Stirling Hwy, Crawley WA 6009 (Australia)

    2010-12-15

    In this paper, we provide an assessment of plantation forests and private land resources potentially available for pine plantation development in 11 southern states of the United States. After a sustained growth for 50 years, plantation forests (softwood and hardwood on both private and public lands) amounted to 18 million ha or 24 percent of all timberlands in these states in 2007. The vast majority of the plantation forests were established on private lands with fast-growing loblolly pines and slash pines. While purposeful hardwood plantations were rare, there were hardwood stands growing on failed pine plantation sites. Using a two-stage Markov land use transition model, we forecast that private forest land in these states will decline about 7 percent or from 66 million ha in 1997 to 61 million ha in 2027, primarily due to urbanization, and that private pine plantations will rise nearly 40 percent from 11 million ha to 16 million ha. Further, growth in pine plantations will decline in coming decades, and states with low population and population growth have the greatest increase in plantations. These plantations, along with other woody biomass, are expected to play an important role in the emerging bio-energy sector. (author)

  6. Modeling Mortality of Loblolly Pine Plantations

    OpenAIRE

    Thapa, Ram

    2014-01-01

    Accurate prediction of mortality is an important component of forest growth and yield prediction systems, yet mortality remains one of the least understood components of the system. Whole-stand and individual-tree mortality models were developed for loblolly pine plantations throughout its geographic range in the United States. The model for predicting stand mortality were developed using stand characteristics and biophysical variables. The models were constructed using two modeling approache...

  7. Sustained mahogany (Swietenia macrophylla) plantation heartwood increment.

    Science.gov (United States)

    Frank H. Wadsworth; Edgardo. Gonzalez

    2008-01-01

    In a search for an increment-based rotation for plantation mahogany(Swietenia macrophylla King), heartwood volume per tree was regressed on DBH (trunk diameter outside bark at 1.4 m above the ground) and merchantable height measurements. We updated a previous study [Wadsworth, F.H., González González, E., Figuera Colón, J.C., Lugo P...

  8. Phylogeny and ecophysiology of opportunistic "snow molds" from a subalpine forest ecosystem.

    Science.gov (United States)

    Schmidt, S K; Wilson, K L; Meyer, A F; Gebauer, M M; King, A J

    2008-11-01

    Mats of coenocytic "snow molds" are commonly observed covering the soil and litter of alpine and subalpine areas immediately following snow melt. Here, we describe the phylogenetic placement, growth rates, and metabolic potential of cold-adapted fungi from under-snow mats in the subalpine forests of Colorado. SSU rDNA sequencing revealed that these fungi belong to the zygomycete orders Mucorales and Mortierellales. All of the isolates could grow at temperatures observed under the snow at our sites (0 degrees C and -2 degrees C) but were unable to grow at temperatures above 25 degrees C and were unable to grow anaerobically. Growth rates for these fungi were very high at -2 degrees C, approximately an order of magnitude faster than previously studied cold-tolerant fungi from Antarctic soils. Given the rapid aerobic growth of these fungi at low temperatures, we propose that they are uniquely adapted to take advantage of the flush of nutrient that occurs at the soil-snow interface beneath late winter snow packs. In addition, extracellular enzyme production was relatively high for the Mucorales, but quite low for the Mortierellales, perhaps indicating some niche separation between these fungi beneath the late winter snow pack.

  9. Subalpine Pyrenees received higher nitrogen deposition than predicted by EMEP and CHIMERE chemistry-transport models

    Science.gov (United States)

    Boutin, Marion; Lamaze, Thierry; Couvidat, Florian; Pornon, André

    2015-08-01

    Deposition of reactive nitrogen (N) from the atmosphere is expected to be the third greatest driver of biodiversity loss by the year 2100. Chemistry-transport models are essential tools to estimate spatially explicit N deposition but the reliability of their predictions remained to be validated in mountains. We measured N deposition and air concentration over the subalpine Pyrenees. N deposition was found to range from 797 to 1,463 mg N m-2 year-1. These values were higher than expected from model predictions, especially for nitrate, which exceeded the estimations of EMEP by a factor of 2.6 and CHIMERE by 3.6. Our observations also displayed a reversed reduced-to-oxidized ratio in N deposition compared with model predictions. The results highlight that the subalpine Pyrenees are exposed to higher levels of N deposition than expected according to standard predictions and that these levels exceed currently recognized critical loads for most high-elevation habitats. Our study reveals a need to improve the evaluation of N deposition in mountains which are home to a substantial and original part of the world’s biodiversity.

  10. Biogeochemical impacts of wildfires over four millennia in a Rocky Mountain subalpine watershed.

    Science.gov (United States)

    Dunnette, Paul V; Higuera, Philip E; McLauchlan, Kendra K; Derr, Kelly M; Briles, Christy E; Keefe, Margaret H

    2014-08-01

    Wildfires can significantly alter forest carbon (C) storage and nitrogen (N) availability, but the long-term biogeochemical legacy of wildfires is poorly understood. We obtained a lake-sediment record of fire and biogeochemistry from a subalpine forest in Colorado, USA, to examine the nature, magnitude, and duration of decadal-scale, fire-induced ecosystem change over the past c. 4250 yr. The high-resolution record contained 34 fires, including 13 high-severity events within the watershed. High-severity fires were followed by increased sedimentary N stable isotope ratios (δ15N) and bulk density, and decreased C and N concentrations--reflecting forest floor destruction, terrestrial C and N losses, and erosion. Sustained low sediment C : N c. 20-50 yr post-fire indicates reduced terrestrial organic matter subsidies to the lake. Low sedimentary δ15N c. 50-70 yr post-fire, coincident with C and N recovery, suggests diminishing terrestrial N availability during stand development. The magnitude of post-fire changes generally scaled directly with inferred fire severity. Our results support modern studies of forest successional C and N accumulation and indicate pronounced, long-lasting biogeochemical impacts of wildfires in subalpine forests. However, even repeated high-severity fires over millennia probably did not deplete C or N stocks, because centuries between high-severity fires allowed for sufficient biomass recovery. © 2014 The Authors. New Phytologist © 2014 New Phytologist Trust.

  11. Biological and physical influences on the carbon isotope content of CO2 in a subalpine forest snowpack, Niwot Ridge, Colorado

    Science.gov (United States)

    D. R. Bowling; W. J. Massman; S. M. Schaeffer; S. P. Burns; R. K. Monson; M. W. Williams

    2009-01-01

    Considerable research has recently been devoted to understanding biogeochemical processes under winter snow cover, leading to enhanced appreciation of the importance of many winter ecological processes. In this study, a comprehensive investigation of the stable carbon isotope composition (δ 13C) of CO2 within a high-elevation subalpine...

  12. Survival, frost susceptibility, growth, and disease resistance of corkbark and subalpine fir grown for landscape and Christmas trees

    Science.gov (United States)

    Trees from six corkbark fir (Abies lasiocarpa var. arizonica) and 10 subalpine fir (A. lasiocarpa var. lasiocarpa) seed sources were grown at the University of Idaho Sandpoint Research and Extension Center (SREC) and two commercial nurseries in Idaho and Oregon. Post transplant mortality was highest...

  13. Mycorrhiza-plant colonization patterns on a subalpine glacier forefront as a model system of primary succession

    Science.gov (United States)

    Efren Cazares; James M. Trappe; Ari Jumpponen

    2005-01-01

    Lyman glacier in the North Cascades Mountains of Washington has a subalpine forefront characterized by a well-developed terminal moraine, inconspicuous successional moraines, fluting, and outwash. These deposits were depleted of symbiotic fungi when first exposed but colonized by them over time after exposure. Four major groups of plant species in this system are (1)...

  14. Effects of mercury deposition and coniferous forests on the mercury contamination of fish in the south central United States

    Science.gov (United States)

    Drenner, Ray W.; Chumchal, Matthew M.; Jones, Christina M.; Lehmann, Christopher M.B.; Gay, David A.; Donato, David I.

    2013-01-01

    Mercury (Hg) is a toxic metal that is found in aquatic food webs and is hazardous to human and wildlife health. We examined the relationship between Hg deposition, land coverage by coniferous and deciduous forests, and average Hg concentrations in largemouth bass (Micropterus salmoides)-equivalent fish (LMBE) in 14 ecoregions located within all or part of six states in the South Central U.S. In 11 ecoregions, the average Hg concentrations in 35.6-cm total length LMBE were above 300 ng/g, the threshold concentration of Hg recommended by the U.S. Environmental Protection Agency for the issuance of fish consumption advisories. Percent land coverage by coniferous forests within ecoregions had a significant linear relationship with average Hg concentrations in LMBE while percent land coverage by deciduous forests did not. Eighty percent of the variance in average Hg concentrations in LMBE between ecoregions could be accounted for by estimated Hg deposition after adjusting for the effects of coniferous forests. Here we show for the first time that fish from ecoregions with high atmospheric Hg pollution and coniferous forest coverage pose a significant hazard to human health. Our study suggests that models that use Hg deposition to predict Hg concentrations in fish could be improved by including the effects of coniferous forests on Hg deposition.

  15. FULLY AUTOMATED GIS-BASED INDIVIDUAL TREE CROWN DELINEATION BASED ON CURVATURE VALUES FROM A LIDAR DERIVED CANOPY HEIGHT MODEL IN A CONIFEROUS PLANTATION

    Directory of Open Access Journals (Sweden)

    R. J. L. Argamosa

    2016-06-01

    Full Text Available The generation of high resolution canopy height model (CHM from LiDAR makes it possible to delineate individual tree crown by means of a fully-automated method using the CHM’s curvature through its slope. The local maxima are obtained by taking the maximum raster value in a 3 m x 3 m cell. These values are assumed as tree tops and therefore considered as individual trees. Based on the assumptions, thiessen polygons were generated to serve as buffers for the canopy extent. The negative profile curvature is then measured from the slope of the CHM. The results show that the aggregated points from a negative profile curvature raster provide the most realistic crown shape. The absence of field data regarding tree crown dimensions require accurate visual assessment after the appended delineated tree crown polygon was superimposed to the hill shaded CHM.

  16. The role of plantation forestry in sustainable development

    Directory of Open Access Journals (Sweden)

    Ivetić Vladan

    2014-01-01

    Full Text Available The paper gives an overview of types of forest plantations and their role in sustainable development, with an emphasis on the definition of artificially established (planted forests and forest plantations. Forest plantations, the most productive part of planted forests, play a significant role in fulfilling the principles of sustainable development. Plantation forestry can provide additional quantities of roundwood and fuelwood (including biomass, additional products in the form of non-timber forest products and additional services in the form of shelterbelts and phytoremediation.

  17. Melaleuca leucadendron (L): Potentials For Plantation Forestry In ...

    African Journals Online (AJOL)

    Melaleuca leucadendron (L): Potentials For Plantation Forestry In The Coastal Mangrove Area Of Nigeria And The Prospects Of Its Successful Intergration Into Agroforestry Practices Like Aquaforestry And Apisiviculture.

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

    DEFF Research Database (Denmark)

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

    2015-01-01

    the importance of vertical variations in light, temperature, CO2 concentration and humidity within the canopy for fluxes of photosynthesis and transpiration of a boreal coniferous forest in central Sweden. A leaf-level photosynthesis-stomatal conductance model was used for aggregating these processes to canopy...... fluxes, where discrepancies are largely attributable to a lack of forest floor evaporation in the model. Simulations in which vertical heterogeneity was artificially suppressed revealed that the vertical distribution of light is the driver of vertical heterogeneity. Despite large differences between...

  19. Quantifying the Effects of Normalisation of Airborne LiDAR Intensity on Coniferous Forest Leaf Area Index Estimations

    Directory of Open Access Journals (Sweden)

    Haotian You

    2017-02-01

    Full Text Available The range between a sensor and the target, the incidence angle, and the target reflectance, are known factors that can influence the intensity values of LiDAR data and consequently, its use in many applications. However, very few studies have provided a quantitative analysis of the effects of normalisation of these three factors on forest leaf area index (LAI estimations. In this paper, using two coniferous tree species (i.e., Scotch pine and Larch pine as a case study, the effects of intensity normalisation on coniferous forest LAI estimations have, for the first time, been systematically examined and quantified. It was found that the intensity normalisation had a generally positive effect on the improvement of coniferous forest LAI estimations. However, the improvements were very minor. Specifically, the range normalisation did not improve the accuracy of the LAI estimation for either of the two coniferous tree species. The incidence angle and reflectance normalisation improved the accuracy of the LAI estimation for Scotch pine forests; however, they had no effect on the improvement of the LAI estimation for Larch pine forests. This experimental study suggests that range normalisation is not required for forest LAI estimations in areas with small elevation differences (i.e., less than 114 m. The incidence angle and target reflectance normalisation can marginally improve the accuracy of coniferous forest LAI estimations. However, the extent of this improvement varies among species, depending on the choice of incidence angle and reflectance coefficient. Overall, the effects of normalisation of airborne LiDAR intensity on coniferous forest LAI estimations are closely related to topographic conditions (i.e., elevation and slope, the tree species composition, and its associated structural attributes. Therefore, further research should explore the effects of LiDAR intensity normalisation on forest LAI estimations in regions with large elevation

  20. Overland flow connectivity in a forest plantation before and after tree thinning (Tochigi Prefecture, central Japan)

    Science.gov (United States)

    López-Vicente, Manuel; Onda, Yuichi; Sun, Xinchao; Kato, Hiroaki; Gomi, Takashi; Hiraoka, Marino

    2016-04-01

    for timber activities (cut down and extraction). In Sc-2012 the management practices were only done in the forest plantation of K2 and the increment of RC within the affected area was of 20%. In Sc-2013 tree thinning was done in the coniferous plantation of K3 and the increment in RC within all affected areas was of 19%. In the three scenarios the highest values of connectivity appeared in the forest roads and skid trails. These two linear elements played a key role in the values and spatial patterns of RC throughout the catchments. The combined effect of tree thinning and new skid trails in one part of K2 triggered a significant increase of the RC in this area. Areas surrounding the divides were subjected to a small increment in RC (ca. 4.8%) whereas the increment of connectivity within the streams was of 9.3% and 10.6% in Sc-2012 and Sc-2013 related to the values in Sc-2011.

  1. Evaluating the Importance of Plant Functional Traits: the Subalpine and Alpine

    Science.gov (United States)

    Sanchez, A.; Smith, W. K.

    2011-12-01

    Over the past several decades, researchers have attempted to characterize plant groups according to traits that are considered functional, i.e. contributing significantly to fitness. Due to the complexity of measuring fitness, the capability for photosynthetic carbon gain is often used as a proxy. Thus, this approach correlates structural differences to photosynthetic performance, especially those differences that are known to be associated with photosynthesis, are easily measured and inexpensive. At the often sharp boundary between the subalpine forest and alpine community (treeline ecotone), plant structural traits change dramatically, i.e. tall evergreen trees give way abruptly to low-stature shrubs, grasses, forbs, and herbs. Yet, the differences in functional traits, so abundant in the literature for a variety of species and communities, have not been compared contiguous communities such as the subalpine forest and alpine. Can differences in functional traits already identified in the literature also be used to characterize species of these two contrasting communities? Or are there other traits that are most functional and/or, possibly, unique to each community and not the most popular traits reported so far in the literature. Also, does the community structure itself help determine functional traits? For example, the top ten most frequently studied traits (145 total papers from approximately 63 different refereed journals) considered functional include the following (% of the 145 publications): specific leaf area or mass (SLA or SLM 39%), plant height (36%), leaf nitrogen content (34%), leaf size (19%), leaf area (16%), leaf photosynthetic performance (15%), leaf dry matter content (LDMC 15%), leaf mass per unit leaf area (LMA 15%), leaf thickness (15%), and seed mass (14%). In addition, another 120 traits were mentioned as functional, although all fell below a 14% citation rate. Particular focus was placed on this group due to the possibility that they might

  2. High diversity of arbuscular mycorrhizal fungi in a boreal herb-rich coniferous forest.

    Science.gov (United States)

    Opik, Maarja; Moora, Mari; Zobel, Martin; Saks, Ulle; Wheatley, Ron; Wright, Frank; Daniell, Tim

    2008-01-01

    * Here, the diversity of arbuscular mycorrhizal (AM) fungi was determined in a boreal herb-rich coniferous forest in relation to environmental variables. * Root samples of five plant species (Fragaria vesca, Galeobdolon luteum, Hepatica nobilis, Oxalis acetosella and Trifolium pratense) were analysed from stands differing in age and forest management intensity. * Thirty-four Glomeromycota taxa (small-subunit ribosomal RNA gene (SSU rDNA) sequence groups) were detected from 90 root samples (911 clones), including eight new taxa. Sequence groups related to Glomus intraradices were most common (MO-G3 and MO-G13). Samples of H. nobilis were colonized by more AM fungal taxa (3.68 +/- 0.31) than those of O. acetosella (2.69 +/- 0.34), but did not differ significantly in this respect from those of F. vesca (3.15 +/- 0.38). Effects of forest management, host plant species (except above) or season on the number or composition of fungal taxa in root samples were not detected, and neither were they explained by environmental variables (vegetation, soil and light conditions). * This is the most taxon-rich habitat described to date in terms of root-colonizing Glomeromycota. The data demonstrate the importance of temperate coniferous forests as habitats for AM fungi and plants. Lack of obvious fungal community patterns suggests more complex effects of biotic and abiotic factors, and possibly no adverse effect of common forest management practices on AM fungal diversity.

  3. Natural attenuation is enhanced in previously contaminated and coniferous forest soils.

    Science.gov (United States)

    Kauppi, Sari; Romantschuk, Martin; Strömmer, Rauni; Sinkkonen, Aki

    2012-01-01

    Prevalence of organic pollutants or their natural analogs in soil is often assumed to lead to adaptation in the bacterial community, which results in enhanced bioremediation if the soil is later contaminated. In this study, the effects of soil type and contamination history on diesel oil degradation and bacterial adaptation were studied. Mesocosms of mineral and organic forest soil (humus) were artificially treated with diesel oil, and oil hydrocarbon concentrations (GC-FID), bacterial community composition (denaturing gradient gel electrophoresis, DGGE), and oil hydrocarbon degraders (DGGE + sequencing of 16S rRNA genes) were monitored for 20 weeks at 16°C. Degradation was advanced in previously contaminated soils as compared with pristine soils and in coniferous organic forest soil as compared with mineral soil. Contamination affected bacterial community composition especially in the pristine mineral soil, where diesel addition increased the number of strong bands in the DGGE gel. Sequencing of cloned 16S rRNA gene fragments and DGGE bands showed that potential oil-degrading bacteria were found in mineral and organic soils and in both pristine and previously contaminated mesocosms. Fast oil degradation was not associated with the presence of any particular bacterial strain in soil. We demonstrate at the mesocosm scale that previously contaminated and coniferous organic soils are superior environments for fast oil degradation as compared with pristine and mineral soil environments. These results may be utilized in preventing soil pollution and planning soil remediation.

  4. Management Effectiveness of a Secondary Coniferous Forest for Landscape Appreciation and Psychological Restoration.

    Science.gov (United States)

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

    2017-07-18

    We investigated the influence of forest management on landscape appreciation and psychological restoration in on-site settings by exposing respondents to an unmanaged, dense coniferous (crowding) forest and a managed (thinned) coniferous forest; we set the two experimental settings in the forests of the Fuji Iyashinomoroi Woodland Study Center. The respondents were individually exposed to both settings while sitting for 15 min and were required to answer three questionnaires to analyze the psychological restorative effects before and after the experiment (feeling (the Profile of Mood States), affect (the Positive and Negative Affect Schedule), and subjective restorativeness (the Restorative Outcome Scale). To compare landscape appreciation, they were required to answer another two questionnaires only after the experiment, for scene appreciation (the semantic differential scale) and for the restorative properties of each environment (the Perceived Restorativeness Scale). Finally, we obtained these findings: (1) the respondents evaluated each forest environment highly differently and evaluated the thinned forest setting more positively; (2) the respondents' impressions of the two physical environments did not appear to be accurately reflected in their evaluations; (3) forest environments have potential restorative effects whether or not they are managed, but these effects can be partially enhanced by managing the forests.

  5. Intrastorm scale rainfall interception dynamics in a mature coniferous forest stand

    Science.gov (United States)

    Iida, Shin'ichi; Levia, Delphis F.; Shimizu, Akira; Shimizu, Takanori; Tamai, Koji; Nobuhiro, Tatsuhiko; Kabeya, Naoki; Noguchi, Shoji; Sawano, Shinji; Araki, Makoto

    2017-05-01

    Canopy interception of rainfall is an important process in the water balance of forests. The intrastorm dynamics of canopy interception is less well understood than event scale interception. Accordingly, armed with measurements of hourly interception intensity (i) from the field, this study is among the first to examine the differences in canopy interception dynamics between the first and second halves of rainfall events to quantify dynamic storage values for a coniferous forest in Japan. At this site, experimental results demonstrated that: (1) the relationship between interception loss (I) and gross rainfall (GR) at the event scale is better explained by a parabolic curve than a linear relationship, and there is a low correlation between rainfall intensity (gr) and i; (2) the ratio of accumulated i during the first half (IF) to that of gr (GRF) was larger than the second half (IS/GRS), with no significant correlations between potential evaporation during first half (PEF) vs IF or the second half (PES) vs IS; and (3) water storage capacity was similar to the magnitude of maximum I. By emphasizing the comparison between IF and IS, this study concludes that the water storage on tree surface is more important than losses by wet canopy evaporation and splash during rain. This study also adds insights into intrastorm interception dynamics of coniferous forests which are necessary to better model and forecast interception losses.

  6. Natural coniferous resin lacquer in treatment of toenail onychomycosis: an observational study.

    Science.gov (United States)

    Sipponen, Pentti; Sipponen, Arno; Lohi, Jouni; Soini, Marjo; Tapanainen, Riikka; Jokinen, Janne J

    2013-05-01

    In in vitro tests, natural coniferous resin from the Norway spruce (Picea abies) is strongly antifungal. In this observational study, we tested the clinical effectiveness of a lacquer composed of spruce resin for topical treatment of onychomycosis. Thirty-seven patients with clinical diagnosis of onychomycosis were enrolled into the study. All patients used topical resin lacquer treatment daily for 9 months. A mycological culture and potassium hydroxide (KOH) stain were done from nail samples in the beginning and in the end of the study. Treatment was considered effective, if a mycological culture was negative and there was an apparent clinical cure. At study entry, 20 patients (20/37; 54%; 95% CI: 38-70) had a positive mycological culture and/or positive KOH stain for dermatophytes. At study end, the result of 13 patients was negative (13/19; 68%; 95% CI: 48-89). In one case (1/14; 7%; 95% CI: 0-21) the mycological culture was initially negative, but it turned positive during the study period. By 14 compliant patients (14/32; 44%; 95% CI: 27-61), resin lacquer treatment was considered clinically effective: complete healing took place in three cases (9%) and partial healing in 11 cases (85%). The results indicate some evidence of clinical efficacy of the natural coniferous resin used for topical treatment of onychomycosis. © 2012 Blackwell Verlag GmbH.

  7. Management Effectiveness of a Secondary Coniferous Forest for Landscape Appreciation and Psychological Restoration

    Science.gov (United States)

    Fujiwara, Akio; Saito, Haruo; Horiuchi, Masahiro

    2017-01-01

    We investigated the influence of forest management on landscape appreciation and psychological restoration in on-site settings by exposing respondents to an unmanaged, dense coniferous (crowding) forest and a managed (thinned) coniferous forest; we set the two experimental settings in the forests of the Fuji Iyashinomoroi Woodland Study Center. The respondents were individually exposed to both settings while sitting for 15 min and were required to answer three questionnaires to analyze the psychological restorative effects before and after the experiment (feeling (the Profile of Mood States), affect (the Positive and Negative Affect Schedule), and subjective restorativeness (the Restorative Outcome Scale). To compare landscape appreciation, they were required to answer another two questionnaires only after the experiment, for scene appreciation (the semantic differential scale) and for the restorative properties of each environment (the Perceived Restorativeness Scale). Finally, we obtained these findings: (1) the respondents evaluated each forest environment highly differently and evaluated the thinned forest setting more positively; (2) the respondents’ impressions of the two physical environments did not appear to be accurately reflected in their evaluations; (3) forest environments have potential restorative effects whether or not they are managed, but these effects can be partially enhanced by managing the forests. PMID:28718831

  8. High tonnage harvesting and skidding for loblolly pine energy plantations

    Science.gov (United States)

    Patrick Jernigan; Tom Gallagher; Dana Mitchell; Mathew Smidt; Larry Teeter

    2016-01-01

    The southeastern United States has a promising source for renewable energy in the form of woody biomass. To meet the energy needs, energy plantations will likely be utilized. These plantations will contain a high density of small-stem pine trees. Since the stems are relatively small when compared with traditional product removal, the harvesting costs will increase. The...

  9. Impacts of Smallholder Tree Plantation in Amhara Region of Ethiopia

    African Journals Online (AJOL)

    Optiplex 7010 Pro

    Forest plantation practices in Ethiopia are mainly of exotic tree species with .... for forest plantation. Especially, Eucalyptus globules and Cupresses lustanica tree species are widely planted in this district. Fagta Locuma district has a total land ..... management practices such as soil bounds, stone bounds, check dams and.

  10. Harvesting Costs For Mechanized Thinning Systems In Slash Pine Plantations

    Science.gov (United States)

    James E. Granskog

    1978-01-01

    Harvesting costs of four tree harvester systems are estimated for row thinning slash pine plantations. Systems incorporating a full-tree type harvester had lower harvesting costs per cord than shortwood and tree-length harvester systems in 15-year-old plantations.

  11. Soil Organic Carbon Dynamics under Different Plantation Crops of ...

    African Journals Online (AJOL)

    Increasing the carbon sequestration potential of the soil is one of the ways to address the increasing build-up of greenhouse gases especially carbon dioxide. A study was conducted to assess the organic carbon pool under Young and Old tree plantations at Uhonmora, Edo State, Nigeria. The plantation species included ...

  12. Heavy metals in soils of cocoa plantation (Theobroma cacao L.)

    Science.gov (United States)

    Cocoa has experienced significant growth in recent years in Peru and the presence of heavy metals in the soils of these plantations is a potential problem for the export of this product. Contents of heavy metals (Cd, Ni, Pb, Fe, Cu, Zn, Mn) in soils from 19 plantations that have been in production f...

  13. Acacia plantations in Vietnam: Research and knowledge application ...

    African Journals Online (AJOL)

    Vietnam has established 1.1 million ha of acacia plantations for wood production, managed on 5- to 10-year rotation cycles. Nearly 50% of the resource is managed by small growers holding 1–5 ha woodlots. Acacia plantations have emerged as an important resource for supporting the rural economy and national export ...

  14. Plantation Forestry in Sub Saharan Africa: Silvicultural, Ecological ...

    African Journals Online (AJOL)

    This paper discusses the potentials of meeting the wood demand and achieving SFM in Sub-Saharan Africa (SSA) through the establishment of forest plantations. The paper reviews forest plantation ownership and distribution patterns in SSA and the factors –silvicultural, ecological, and economic that affect supply and ...

  15. The role of plantation forests in rehabilitating degraded tropical ecosystems

    Science.gov (United States)

    John A. Parrotta

    1992-01-01

    Plantations of multi-purpose tree species can play an important role in restoring productivity, ecosyste~ 2n stability, and biological diversity to degraded tropical lands. The present study, conducted at a degraded coastal pasture site in Puerto Rico, compares 4.5-year-old Aibizia lebbek (L.) Benth. plantation stands and adjacent control areas with respect to biomass...

  16. Green gold : on variations of truth in plantation forestry

    NARCIS (Netherlands)

    Romeijn, P.

    1999-01-01

    The "variations of truth in plantation forestry" is a study on the Teakwood investment program. Teakwood offered the general public in The Netherlands the opportunity to directly invest in a teak plantation in Costa Rica. The program was pioneered in 1989 and truly gained momentum when it

  17. Early height growth of ponderosa pine forecasts dominance in plantations

    Science.gov (United States)

    William W. Oliver; Robert F. Powers

    1971-01-01

    Future crown class may be determined well in advance of intertree competition in plantation grown ponderosa pine. Regardless of site quality, dominant trees in 10 California plantations reached breast height ½ year sooner than codominants and 1-½ years sooner than intermediates. Dominant trees on poor sites reached breast height several years earlier than has been...

  18. Thinning guidelines from crown area relationships for young hardwood plantations

    Science.gov (United States)

    Jeffrey W. Stringer; Luke Cecil

    2010-01-01

    Crown closure in hardwood plantations signals the first opportunity to apply density control treatments such as thinning or release. The proper timing of these treatments is a function of stocking levels and is generally scheduled within several years after initial crown closure. Predicting crown closure for a plantation provides practitioners with the ability to plan...

  19. Characterization of weed flora in rubber trees plantations of Bongo ...

    African Journals Online (AJOL)

    Objectives: the main objective of this study is to characterize the weed floristic diversity of the Bongo rubber trees plantation and to provide a map for sustainable weed management. Methodology and results: a floristic survey of the Para rubber plantations of Bongo (Southeast Côte d'Ivoire) was conducted in 2007 and early ...

  20. Wildlife and invertebrate response to fuel reduction treatments in dry coniferous forests of the Western United States: a synthesis

    Science.gov (United States)

    David S. Pilliod; Evelyn L. Bull; Jane L. Hayes; Barbara C. Wales

    2006-01-01

    This paper synthesizes available information on the effects of hazardous fuel reduction treatments on terrestrial wildlife and invertebrates in dry coniferous forest types in the West. We focused on thinning and/or prescribed fire studies in ponderosa pine (Pinus ponderosa) and dry-type Douglas-fir (Pseudotsuga menziesii),...

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

    Science.gov (United States)

    Erich Kyle Dodson; David W. Peterson

    2010-01-01

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

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

    Science.gov (United States)

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

    2006-01-01

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

  3. Minimizing measurement uncertainties of coniferous needle-leaf optical properties, part II: experimental set-up and error analysis

    NARCIS (Netherlands)

    Yanez Rausell, L.; Malenovsky, Z.; Clevers, J.G.P.W.; Schaepman, M.E.

    2014-01-01

    We present uncertainties associated with the measurement of coniferous needle-leaf optical properties (OPs) with an integrating sphere using an optimized gap-fraction (GF) correction method, where GF refers to the air gaps appearing between the needles of a measured sample. We used an optically

  4. Recent pollen spectra from the deciduous and coniferous-deciduous forests of Northeastern Minnesota: a study in pollen dispersal

    NARCIS (Netherlands)

    Janssen, C.R.

    1966-01-01

    Pollen samples were taken along nine transects across local vegetational belts bordering bogs or ponds in overall deciduous and coniferous-deciduous forest regions. Three types of pollen rain are distinguished: local, extralocal, and regional. Local pollen rain is derived from plants that grow at or

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

    NARCIS (Netherlands)

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

    1997-01-01

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

  6. Impact of interspecific interactions on the soil water uptake depth in a young temperate mixed species plantation

    Science.gov (United States)

    Grossiord, Charlotte; Gessler, Arthur; Granier, André; Berger, Sigrid; Bréchet, Claude; Hentschel, Rainer; Hommel, Robert; Scherer-Lorenzen, Michael; Bonal, Damien

    2014-11-01

    Interactions between tree species in forests can be beneficial to ecosystem functions and services related to the carbon and water cycles by improving for example transpiration and productivity. However, little is known on below- and above-ground processes leading to these positive effects. We tested whether stratification in soil water uptake depth occurred between four tree species in a 10-year-old temperate mixed species plantation during a dry summer. We selected dominant and co-dominant trees of European beech, Sessile oak, Douglas fir and Norway spruce in areas with varying species diversity, competition intensity, and where different plant functional types (broadleaf vs. conifer) were present. We applied a deuterium labelling approach that consisted of spraying labelled water to the soil surface to create a strong vertical gradient of the deuterium isotope composition in the soil water. The deuterium isotope composition of both the xylem sap and the soil water was measured before labelling, and then again three days after labelling, to estimate the soil water uptake depth using a simple modelling approach. We also sampled leaves and needles from selected trees to measure their carbon isotope composition (a proxy for water use efficiency) and total nitrogen content. At the end of the summer, we found differences in the soil water uptake depth between plant functional types but not within types: on average, coniferous species extracted water from deeper layers than did broadleaved species. Neither species diversity nor competition intensity had a detectable influence on soil water uptake depth, foliar water use efficiency or foliar nitrogen concentration in the species studied. However, when coexisting with an increasing proportion of conifers, beech extracted water from progressively deeper soil layers. We conclude that complementarity for water uptake could occur in this 10-year-old plantation because of inherent differences among functional groups (conifers

  7. Regional Mapping of Plantation Extent Using Multisensor Imagery

    Directory of Open Access Journals (Sweden)

    Nathan Torbick

    2016-03-01

    Full Text Available Industrial forest plantations are expanding rapidly across Monsoon Asia and monitoring extent is critical for understanding environmental and socioeconomic impacts. In this study, new, multisensor imagery were evaluated and integrated to extract the strengths of each sensor for mapping plantation extent at regional scales. Two distinctly different landscapes with multiple plantation types were chosen to consider scalability and transferability. These were Tanintharyi, Myanmar and West Kalimantan, Indonesia. Landsat-8 Operational Land Imager (OLI, Phased Array L-band Synthetic Aperture Radar-2 (PALSAR-2, and Sentinel-1A images were fused within a Classification and Regression Tree (CART framework using random forest and high-resolution surveys. Multi-criteria evaluations showed both L-and C-band gamma nought γ° backscatter decibel (dB, Landsat reflectance ρλ, and texture indices were useful for distinguishing oil palm and rubber plantations from other land types. The classification approach identified 750,822 ha or 23% of the Taninathryi, Myanmar, and 216,086 ha or 25% of western West Kalimantan as plantation with very high cross validation accuracy. The mapping approach was scalable and transferred well across the different geographies and plantation types. As archives for Sentinel-1, Landsat-8, and PALSAR-2 continue to grow, mapping plantation extent and dynamics at moderate resolution over large regions should be feasible.

  8. Regional Mapping of Plantation Extent Using Multisensor Imagery

    Science.gov (United States)

    Torbick, N.; Ledoux, L.; Hagen, S.; Salas, W.

    2016-12-01

    Industrial forest plantations are expanding rapidly across the tropics and monitoring extent is critical for understanding environmental and socioeconomic impacts. In this study, new, multisensor imagery were evaluated and integrated to extract the strengths of each sensor for mapping plantation extent at regional scales. Three distinctly different landscapes with multiple plantation types were chosen to consider scalability and transferability. These were Tanintharyi, Myanmar, West Kalimantan, Indonesia, and southern Ghana. Landsat-8 Operational Land Imager (OLI), Phased Array L-band Synthetic Aperture Radar-2 (PALSAR-2), and Sentinel-1A images were fused within a Classification and Regression Tree (CART) framework using random forest and high-resolution surveys. Multi-criteria evaluations showed both L-and C-band gamma nought γ° backscatter decibel (dB), Landsat reflectance ρλ, and texture indices were useful for distinguishing oil palm and rubber plantations from other land types. The classification approach identified 750,822 ha or 23% of the Taninathryi, Myanmar, and 216,086 ha or 25% of western West Kalimantan as plantation with very high cross validation accuracy. The mapping approach was scalable and transferred well across the different geographies and plantation types. As archives for Sentinel-1, Landsat-8, and PALSAR-2 continue to grow, mapping plantation extent and dynamics at moderate resolution over large regions should be feasible.

  9. Comparison of remote sensing and plant trait-based modelling to predict ecosystem services in subalpine grasslands

    Czech Academy of Sciences Publication Activity Database

    Homolová, Lucie; Schaepman, M. E.; Lamarque, L.; Clevers, J.G.P.W.; de Bello, Francesco; Thuiller, W.; Lavorel, S.

    2014-01-01

    Roč. 5, č. 8 (2014), č. článku 100. ISSN 2150-8925 Institutional support: RVO:67179843 ; RVO:67985939 Keywords : land-use change * leaf chlorophyll content * imaging spectroscopy * water-content * aviris data * spectral reflectance * hyperspectral data * species richness * area index * vegetation * aisa * biomass * ecosystem properties * ecosystem services * linear regression * remote sensing * spatial heterogeneity * subalpine grasslands Subject RIV: EH - Ecology, Behaviour; EF - Botanics (BU-J) Impact factor: 2.255, year: 2014

  10. The Effect of Re-Planting Trees on Soil Microbial Communities in a Wildfire-Induced Subalpine Grassland

    OpenAIRE

    Ed-Haun Chang; Guanglong Tian; Chih-Yu Chiu

    2017-01-01

    Wildfire often causes tremendous changes in ecosystems, particularly in subalpine and alpine areas, which are vulnerable due to severe climate conditions such as cold temperature and strong wind. This study aimed to clarify the effect of tree re-planting on ecosystem services such as the soil microbial community after several decades. We compared the re-planted forest and grassland with the mature forest as a reference in terms of soil microbial biomass C and N (Cmic and Nmic), enzyme activit...

  11. Effects of long-term population fluctuations of a top predator on invertebrate communities in subalpine ponds in Colorado

    OpenAIRE

    Wissinger, S.; Whiteman, H.; Denoël, Mathieu; Greig, H.; Butkas, K.

    2006-01-01

    Experimental and comparative data from subalpine ponds with and without tiger salamanders (Ambystoma tigrinum nebulosum) suggest that this species is a keystone predator on benthic and planktonic prey communities. At our study site in central Colorado, the population size of salamanders has fluctuated cyclically over the past 20 years from fewer than 100 to over 5000 individuals. Here we present long-term benthic data that reveal taxon- and habitat-specific correlations with fluctuations in s...

  12. Climate Risk Modelling of Balsam Woolly Adelgid Damage Severity in Subalpine Fir Stands of Western North America.

    Science.gov (United States)

    Hrinkevich, Kathryn H; Progar, Robert A; Shaw, David C

    2016-01-01

    The balsam woolly adelgid (Adelges piceae (Ratzeburg) (Homoptera: Adelgidae)) (BWA) is a nonnative, invasive insect that threatens Abies species throughout North America. It is well established in the Pacific Northwest, but continues to move eastward through Idaho and into Montana and potentially threatens subalpine fir to the south in the central and southern Rocky Mountains. We developed a climatic risk model and map that predicts BWA impacts to subalpine fir using a two-step process. Using 30-year monthly climate normals from sites with quantitatively derived BWA damage severity index values, we built a regression model that significantly explained insect damage. The sites were grouped into two distinct damage categories (high damage and mortality versus little or no mortality and low damage) and the model estimates for each group were used to designate distinct value ranges for four climatic risk categories: minimal, low, moderate, and high. We then calculated model estimates for each cell of a 4-kilometer resolution climate raster and mapped the risk categories over the entire range of subalpine fir in the western United States. The spatial variation of risk classes indicates a gradient of climatic susceptibility generally decreasing from the Olympic Peninsula in Washington and the Cascade Range in Oregon and Washington moving eastward, with the exception of some high risk areas in northern Idaho and western Montana. There is also a pattern of decreasing climatic susceptibility from north to south in the Rocky Mountains. Our study provides an initial step for modeling the relationship between climate and BWA damage severity across the range of subalpine fir. We showed that September minimum temperature and a metric calculated as the maximum May temperature divided by total May precipitation were the best climatic predictors of BWA severity. Although winter cold temperatures and summer heat have been shown to influence BWA impacts in other locations, these

  13. The Response of Subalpine Vegetation to Climate Change and Bark Beetle Infestations: A Multi-Scale Interaction.

    Science.gov (United States)

    Foster, A.; Shuman, J. K.; Shugart, H. H., Jr.; Negrón, J. F.

    2015-12-01

    Mean annual temperatures in the western United States have increased in the last few decades, and are predicted to continue warming. In the subalpine zone of the Rocky Mountains, this warming is also predicted to increase the frequency and severity of spruce beetle outbreaks. Climate change itself may affect this vegetation, potentially leading to shifts in species compositions. These forests are a crucial part of the US's carbon budget, thus it is important to analyze how climate change and bark beetles in conjunction will affect the biomass and species composition of vegetation in subalpine zone. UVAFME is an individual-based gap model that simulates biomass and species composition of a forest. This model has been quantitatively tested at various Rocky Mountain sites in the Front Range, and has been shown to accurately simulate the vegetation dynamics in the region. UVAFME has been updated with a spruce beetle subroutine that calculates the probability for beetle infestation of each tree on a plot. This probability is based on site, climate, and individual tree characteristics, such as temperature; stand structure; and tree stress level, size, and age. These governing characteristics are based on data from the US Forest Service, and other studies on spruce susceptibility and spruce beetle phenology. UVAFME is then run with multiple climate change and beetle scenarios to determine the net effect of both variables on subalpine vegetation. These results are compared among the different scenarios and to current forest inventory data. We project that increasing temperatures due to climate change will cause an increase in the frequency and severity of spruce beetle outbreaks, leading to a decrease in the biomass and dominance of Engelmann spruce. These results are an important step in understanding the possible futures for the vegetation of subalpine zone in the Rocky Mountains.

  14. Climate Risk Modelling of Balsam Woolly Adelgid Damage Severity in Subalpine Fir Stands of Western North America.

    Directory of Open Access Journals (Sweden)

    Kathryn H Hrinkevich

    Full Text Available The balsam woolly adelgid (Adelges piceae (Ratzeburg (Homoptera: Adelgidae (BWA is a nonnative, invasive insect that threatens Abies species throughout North America. It is well established in the Pacific Northwest, but continues to move eastward through Idaho and into Montana and potentially threatens subalpine fir to the south in the central and southern Rocky Mountains. We developed a climatic risk model and map that predicts BWA impacts to subalpine fir using a two-step process. Using 30-year monthly climate normals from sites with quantitatively derived BWA damage severity index values, we built a regression model that significantly explained insect damage. The sites were grouped into two distinct damage categories (high damage and mortality versus little or no mortality and low damage and the model estimates for each group were used to designate distinct value ranges for four climatic risk categories: minimal, low, moderate, and high. We then calculated model estimates for each cell of a 4-kilometer resolution climate raster and mapped the risk categories over the entire range of subalpine fir in the western United States. The spatial variation of risk classes indicates a gradient of climatic susceptibility generally decreasing from the Olympic Peninsula in Washington and the Cascade Range in Oregon and Washington moving eastward, with the exception of some high risk areas in northern Idaho and western Montana. There is also a pattern of decreasing climatic susceptibility from north to south in the Rocky Mountains. Our study provides an initial step for modeling the relationship between climate and BWA damage severity across the range of subalpine fir. We showed that September minimum temperature and a metric calculated as the maximum May temperature divided by total May precipitation were the best climatic predictors of BWA severity. Although winter cold temperatures and summer heat have been shown to influence BWA impacts in other

  15. The low-temperature method for study of coniferous tissues in the environmental scanning electron microscope.

    Science.gov (United States)

    Neděla, Vilém; Tihlaříková, Eva; Hřib, Jiří

    2015-01-01

    The use of non-standard low-temperature conditions in environmental scanning electron microscopy might be promising for the observation of coniferous tissues in their native state. This study is aimed to analyse and evaluate the method based on the principle of low-temperature sample stabilization. We demonstrate that the upper mucous layer is sublimed and a microstructure of the sample surface can be observed with higher resolution at lower gas pressure conditions, thanks to a low-temperature method. An influence of the low-temperature method on sample stability was also studied. The results indicate that high-moisture conditions are not suitable for this method and often cause the collapse of samples. The potential improvement of stability to beam damage has been demonstrated by long-time observation at different operation parameters. We finally show high applicability of the low-temperature method on different types of conifers and Oxalis acetosella. © 2014 Wiley Periodicals, Inc.

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

    DEFF Research Database (Denmark)

    Kjøller, Rasmus; Clemmensen, Karina

    2009-01-01

    In this study we report on changes in the belowground ectomycorrhizal fungal communities in southern Swedish coniferous forests as a consequence of liming with 3-7 ton limestone per hectare 16 years prior to the study. A total of 107 ectomycorrhizal fungi were identified from 969 independently...... were colonised by a different fungal species as a consequence of liming. The observed shift in ectomycorrhizal fungal communities was related to an increased pH and base saturation with liming. We conclude that even a moderate level of liming have long lasting effects on belowground ectomycorrhizal...... community composition. We discuss the observed community changes in relation to ectomycorrhizal functionality and biodiversity in limed forests....

  17. A composite L-band HH radar backscattering model for coniferous forest stands

    Science.gov (United States)

    Sun, Guoquing; Simonett, David S.

    1988-01-01

    The radar backscattering model developed by Richards et al. (1987), has been improved and further tested in this research. The trunk term may now be calculated from the exact solution to the electromagnetic wave equations instead of the corner reflector equation. Rough surface models have been introduced into the radar model, so that the forward reflectance and the backscattering from the ground surface are now calculated from the same model and, thus, are consistent. The number of trees in an individual pixel is assumed to be Poisson distributed, with tree height in a stand log-normally distributed. The simulated results show that the match of backscattering coefficients for eight forest stands between SIR-B image data and the simulated results are satisfying, and that the trunk term now seems to be convincingly established as the dominant term in the L-band HH radar return from coniferous forest stands.

  18. Mechanisms of Odor Coding in Coniferous Bark Beetles: From Neuron to Behavior and Application

    Directory of Open Access Journals (Sweden)

    Martin N. Andersson

    2012-01-01

    Full Text Available Coniferous bark beetles (Coleoptera: Curculionidae: Scolytinae locate their hosts by means of olfactory signals, such as pheromone, host, and nonhost compounds. Behavioral responses to these volatiles are well documented. However, apart from the olfactory receptor neurons (ORNs detecting pheromones, information on the peripheral olfactory physiology has for a long time been limited. Recently, however, comprehensive studies on the ORNs of the spruce bark beetle, Ips typographus, were conducted. Several new classes of ORNs were described and odor encoding mechanisms were investigated. In particular, links between behavioral responses and ORN responses were established, allowing for a more profound understanding of bark beetle olfaction. This paper reviews the physiology of bark beetle ORNs. Special focus is on I. typographus, for which the available physiological data can be put into a behavioral context. In addition, some recent field studies and possible applications, related to the physiological studies, are summarized and discussed.

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

    DEFF Research Database (Denmark)

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

    2008-01-01

    In this paper, the L-band Microwave Emission of the Biosphere (L-MEB) model used in the Soil Moisture and Ocean Salinity (SMOS) Level 2 Soil Moisture algorithm is calibrated using L-band (1.4 GHz) microwave measurements over a coniferous (Pine) and a deciduous (mixed/Beech) forest. This resulted...... temperatures from 2.8 to 3.8 K, depending on data set and polarization. Furthermore, the relationship between canopy optical depth and leaf area index is investigated for the deciduous site. Finally, a sensitivity study is conducted for the focus parameters, temperature, soil moisture, and precipitation....... The results found in this paper will be integrated in the operational SMOS Level 2 Soil Moisture algorithm and used in future inversions of the L-MEB model, for soil moisture retrievals over heterogeneous, partly forested areas....

  20. Using a LIDAR Vegetation Model to Predict UHF SAR Attenuation in Coniferous Forests.

    Science.gov (United States)

    Swanson, Alan; Huang, Shengli; Crabtree, Robert

    2009-01-01

    Attenuation of radar signals by vegetation can be a problem for target detection and GPS reception, and is an important parameter in models describing vegetation backscatter. Here we first present a model describing the 3D distribution of stem and foliage structure based on small footprint scanning LIDAR data. Secondly we present a model that uses ray-tracing methodology to record detailed interactions between simulated radar beams and vegetation components. These interactions are combined over the SAR aperture and used to predict two-way attenuation of the SAR signal. Accuracy of the model is demonstrated using UHF SAR observations of large trihedral corner reflectors in coniferous forest stands. Our study showed that the model explains between 66% and 81% of the variability in observed attenuation.

  1. Using a LIDAR Vegetation Model to Predict UHF SAR Attenuation in Coniferous Forests

    Directory of Open Access Journals (Sweden)

    Alan Swanson

    2009-03-01

    Full Text Available Attenuation of radar signals by vegetation can be a problem for target detection and GPS reception, and is an important parameter in models describing vegetation backscatter. Here we first present a model describing the 3D distribution of stem and foliage structure based on small footprint scanning LIDAR data. Secondly we present a model that uses ray-tracing methodology to record detailed interactions between simulated radar beams and vegetation components. These interactions are combined over the SAR aperture and used to predict two-way attenuation of the SAR signal. Accuracy of the model is demonstrated using UHF SAR observations of large trihedral corner reflectors in coniferous forest stands. Our study showed that the model explains between 66% and 81% of the variability in observed attenuation.

  2. The Effect of Re-Planting Trees on Soil Microbial Communities in a Wildfire-Induced Subalpine Grassland

    Directory of Open Access Journals (Sweden)

    Ed-Haun Chang

    2017-10-01

    Full Text Available Wildfire often causes tremendous changes in ecosystems, particularly in subalpine and alpine areas, which are vulnerable due to severe climate conditions such as cold temperature and strong wind. This study aimed to clarify the effect of tree re-planting on ecosystem services such as the soil microbial community after several decades. We compared the re-planted forest and grassland with the mature forest as a reference in terms of soil microbial biomass C and N (Cmic and Nmic, enzyme activities, phospholipid fatty acids (PLFA composition, and denaturing gradient gel electrophoresis (DGGE. The Cmic and Nmic did not differ among the grassland, re-planted forest and mature forest soil; however, ratios of Cmic/Corg and Nmic/Ntot decreased from the grassland to re-planted forest and mature forest soil. The total PLFAs and those attributed to bacteria and Gram-positive and Gram-negative bacteria did not differ between the re-planted forest and grassland soil. Principle component analysis of the PLFA content separated the grassland from re-planted forest and mature forest soil. Similarly, DGGE analysis revealed changes in both bacterial and fungal community structures with changes in vegetation. Our results suggest that the microbial community structure changes with the re-planting of trees after a fire event in this subalpine area. Recovery of the soil microbial community to the original state in a fire-damaged site in a subalpine area may require decades, even under a re-planted forest.

  3. Responses Of Subalpine Conifer Seedling Germination And Survival To Soil Microclimate In The Alpine Treeline Warming Experiment

    Science.gov (United States)

    Castanha, C.; Moyes, A. B.; Torn, M. S.; Germino, M. J.; Kueppers, L. M.

    2011-12-01

    At Niwot Ridge, Colorado, we used common gardens and climate manipulations to investigate potential subalpine tree species range shifts due to climate change. In Fall 2009 we harvested seed from local populations of limber pine and Englemann spruce, which we sowed in 3 experimental sites spanning an elevation gradient from lower subalpine forest (3080m asl), to the upper subalpine treeline ecotone (3400m asl), to the alpine tundra (3550m asl). In October we turned on overhead infrared heaters designed to increase growing season surface soil temperature by 4-5°C, and following snowmelt in 2010 we crossed this heating treatment with manual watering, adding 3mm of water each week. Here we report on the species, site, and treatment effects on seedling emergence and survival as mediated by snowmelt date, soil temperature, and soil moisture. Depending on the site and plot, heating accelerated germination by 1 to 4 weeks. Germination degree days (heat accumulation required for seed germination) were greater for pine than for spruce and greater in drier plots. Seedling survival was explained by date of emergence, with older seedlings more likely to survive the season. Survival was also explained by drought degree days -- the number of days below critical soil moisture thresholds compounded by high temperature -- with lower thresholds for spruce than for pine. Our preliminary results indicate that a warmer environment will stimulate germination for both species, but that, survival - especially for spruce - will be critically modulated by summer soil moisture.

  4. Pesticide pollution status in cocoa plantation soil

    Directory of Open Access Journals (Sweden)

    E. Atuanya

    2017-09-01

    Full Text Available Management of cocoa plantation field relied on the use of pesticides over the years; hence, the fate of such chemicals is one of the most debated issues among the stakeholders. Young and old cocoa plantation fields from 4 major cocoa producing States in Nigeria were selected as the study area. Eight composites soil samples collected from 3 portions of 6 transect measured area (100 x 50m of the field were transported to the laboratory in sterile glass jar for analysis. A total of 19 organochlorine pesticides residues; (aldrin, α-hexachlorohexane, β-hexachlorohexane, γ-hexachlorohexane, δ-hexachlorohexane, α-chlordane, γ-chlordane, p,p’-dichlorodiphenyldichloroethane, p,p’-dichlorodiphenyldichloroethylene, p,p’-dichlorodiphenyltrichloroethane, dieldrin, endosulfan I, endosulfan-II, endosulfan sulfate, endrin, endrin aldehydes, heptachlor, heptachlor epoxide and metoxychlor were analyzed with gas chromatography equipped with electron capture detector. The results revealed the variation in the number of residues detected among the study fields. Endosulfan-I had the highest value g organochlorine pesticides residue detected. Most of the residue concentrations were within the European Union regulatory standard of Czech Republic. Other-cyclodine group had the highest concentration value among the evaluated organochlorine pesticides groups. The significant (P < 0.05 higher concentration of total organochlorine pesticides were observed in old fields. Composition quotients values indicate that most of the observed organochlorine pesticides residues were products of historical usage. There were strong correlations among the total organic carbon contents of soils and the total organochlorine pesticides compounds. Government regulatory agencies are encouraged to vigorously embark in further monitoring and ensuring the safety compliance of farmers towards the use of pesticides in Nigeria farms.

  5. Ten-year variability in fluxes, meteorology, and environmental conditions at a Colorado subalpine forest site

    Science.gov (United States)

    Burns, S. P.; Turnipseed, A.; Bowling, D. R.; Hu, J.; Monson, R. K.

    2009-12-01

    Changing meteorological and environmental conditions affect fluxes; model analysis has shown that environmental variability directly accounts for about half the interannual variability in net ecosystem exchange (NEE) of CO2 whereas the other 50% is due to biotic responses to these changing variables (Richardson et al. 2007). In our study, ten years (1998-2008) of turbulent flux measurements of heat, water vapor, and CO2 at the Niwot Ridge AmeriFlux site (Monson et al. 2002) are examined with respect to meteorological conditions (atmospheric temperature, stability, precipitation, and cloudiness) as well as changes in environmental conditions, such as snow depth and soil moisture. The typical yearly cycle and an estimate of the magnitude of year-to-year variability in the diurnal fluxes and other variables for a high-elevation subalpine forest ecosystem are presented. Wintertime ecosystem respiration has an average 30-min NEE of 0.62 μmol m-2 s-1 with an interannual range between 0.5-1 μmol m-2 s-1. Uptake of CO2 in late summer has an average NEE of -0.71 μmol m-2 s-1 with an interannual range between -0.1 to -1.5 μmol m-2 s-1. Previous studies at the Niwot Ridge AmeriFlux site have described the importance of photosynthetic photon flux density (PPFD) (Monson et al. 2002) and also growing season length (Hu et al. 2009) on NEE. Water isotope ratios analyzed by Hu et al. (2009) have shown that trees at the site primarily rely on water from snowmelt to sustain them throughout the summer; combining this result with the SIPNET model, Hu et al. conclude that there is a limited connection between summer precipitation and the cumulative annual gross primary production (GPP). We have tested this conclusion more explicitly by examining the response of NEE to specific precipitation events and the effect of extended dry periods on the diel cycle of the fluxes, CO2 mole fraction, sap flow, and other meteorological and soil variables. Additionally, we examine the connection

  6. Response of subalpine grasslands communities to clear-cut and prescribed burnt to control shrub encroachment in Pyrenees

    Science.gov (United States)

    Alados, Concepción L.; Gartzia, Maite; Nuche, Paloma; Saiz, Hugo; Pueyo, Yolanda

    2017-04-01

    Anthropogenic activities have modified vegetation in subalpine belts for long time, lowering treeline ecotone and influencing landscape mainly through grazing and fire. During the last decades the abandonment of traditional land use practices and global warming are contributing largely to the colonization of woody species in subalpine grasslands causing irreversible changes in ecosystem functioning. To prevent those changes a variety of management strategies are carried out to stop the expansion of the highly encroaching shrubs, which require the use of fire and/or clear-cutting, particularly for the conservation of grasslands in subhumid high productive ecosystems. However, it is still poorly understood how different management strategies affect the recovery of subalpine grasslands. Using a field experiment we tested the impact of management treatments on soil properties and vegetation characteristics, including species richness, community structure, interspecies interaction, and complexity of network association. Vegetation was monitored during four years in eight stands (two stands per treatment) where the vegetation was removed by prescribed fire (Burnt treatment), or by mechanical removal (Clear-cut treatment). Two undisturbed E. horridum stands were used as a control (C-Erizón) and two grassland communities regularly grazed (C-Grass) were used as a control for subalpine grassland. Soils nutrients declined in Burnt treatment 3 years after fire, but not differences between Clear-cut and C-Erizón were observed. Species richness and diversity were larger in C-Grass and lower in C-Erizón. Burnt and Clear-cut treatments increased species diversity and richness gradually after 4 year treatment. The proportion of legume forbs, grasses and non-legume forbs did not reach the levels of C-Grass after 4 years of Clear-cut or Burnt treatments. Shrubs and sub-shrubs increased faster after 4 years of burning than after 4 years of clearing, although they did not reach the

  7. Selected Harvesting Machines For Short Rotation Intensive Culture Biomass Plantations

    Science.gov (United States)

    Sammy Woodfin; Doug Frederick; Bryce Stokes

    1987-01-01

    Three different harvesting systems were observed and analyzed for productivity and costs in a short rotation.intensive culture plantation of 2 to 5 year old sycamore. Individual machines were compared to create an optimum system.

  8. Health Needs Assessment of Older People in an Agricultural Plantation

    National Research Council Canada - National Science Library

    Din, Normah Che; Ghazali, Shazli Ezzat; Ibrahim, Norhayati; Ahmad, Mahadir; Said, Zaini; Ghazali, Ahmad Rohi; Razali, Rosdinom; Shahar, Suzana

    2014-01-01

    Background: Federal Land Development Authority (FELDA) is a unique palm oil and rubber plantation settlement in the rural areas of Malaysia occupied by the land settlers who are now in their old age...

  9. Plantation Patriarchy and Structural Violence: Women Workers in Sri Lanka

    NARCIS (Netherlands)

    R. Kurian (Rachel); K. Jayawardena (Kumari)

    2013-01-01

    markdownabstract__Abstract__ Plantation production began in Sri Lanka in the early 19th century under British colonial rule, when the government provided financial incentives and infrastructural support for the commercialisation and export of agricultural crops in line with promoting

  10. Predicting Site Index in Young Black Walnut Plantations

    Science.gov (United States)

    Craig K. Losche; Richard C. Schlesinger

    1975-01-01

    Prediction of black walnut height at age 25 is graphically represented for two soil-site groups. The landowner or manager can use this growth prediction to assess the productivity of yung black walnut plantations.

  11. Characterization of weed flora in rubber trees plantations of Bongo ...

    African Journals Online (AJOL)

    SARAH

    2013-10-31

    Oct 31, 2013 ... Rubiaceae, Apocynaceae, Poaceae, Cyperaceae, Euphorbiaceae, Moraceae, Amaranthaceae,. Mimosaceae, Fabaceae, Cucurbitaceae and Commelinaceae. Weeds' mapping was established and illustrated by 4 main weed groups in relation with the stage of rubber trees development. For the plantations.

  12. Assessing the Climate Sensitivity of Cold Content and Snowmelt in Seasonal Alpine and Subalpine Snowpacks

    Science.gov (United States)

    Jennings, K. S.; Molotch, N. P.

    2016-12-01

    In cold, high-elevation sites, snowpack cold content acts as a buffer against climate warming by resisting snowmelt during periods of positive energy fluxes. To test the climate sensitivity of cold content and snowmelt, we employed the physical SNOWPACK snow model, forced with a 23-year, hourly, quality-controlled, gap-filled meteorological dataset from the Niwot Ridge Long Term Ecological Research (LTER) site in the Front Range mountains of Colorado. SNOWPACK was run at two points with seasonal snowpacks within the LTER, one in the alpine (3528 m) and one in the subalpine (3022 m). Model output was validated using snow water equivalent (SWE), snowpack temperature, and cold content data from snow pits dug near the met stations and automated SWE data from nearby SNOTEL snow pillows. Cold content accumulates primarily through additions of new snow, while negative energy fluxes—cooling through longwave emission and sublimation—play a lesser role, particularly in the deeper snowpack of the alpine. On average, the snowpack energy balance becomes positive on April 1 in the alpine and March 8 in the subalpine. Peak SWE occurs after these dates and its timing is primarily determined by the amount of precipitation received after peak cold content, with persistent snowfall delaying the main snowmelt pulse. Years with lower cold content, due to reduced precipitation and/or increased air temperature, experience an earlier positive energy balance with more melt events occurring before the date of peak SWE, which has implications for soil moisture, streamflow volume and timing, water uptake by vegetation, and microbial respiration. Synthetic warming experiments show significant cold content reductions and increased late-winter/early-spring melt as positive energy balances occur earlier in the snow season (a forward shift between 5.1 and 21.0 days per °C of warming). These results indicate cold, high-elevation sites, which are critical for water resources in the western

  13. Green gold : on variations of truth in plantation forestry

    OpenAIRE

    Romeijn, P.

    1999-01-01

    The "variations of truth in plantation forestry" is a study on the Teakwood investment program. Teakwood offered the general public in The Netherlands the opportunity to directly invest in a teak plantation in Costa Rica. The program was pioneered in 1989 and truly gained momentum when it was joined by the world's largest environmental organization WWF and an insurance and banking company called OHRA in 1993. Thousands of people invested, many millions of Guilders were transferred an...

  14. Multi-scale patterns of subalpine fir mortality are driven by complex interactions among broad-scale climate, local topography, stand structure, and tree characteristics

    Science.gov (United States)

    Harvey, B. J.; Andrus, R. A.; Orrego, A.; Battaglia, M.; Negrón, J. F.; Veblen, T. T.

    2016-12-01

    Recent tree mortality events across much of western North America have been associated with warming temperatures and elevated drought stress, which can interact with forest stand-structure and tree vigor to drive outbreaks of native insect species. Although cross-scale interactions among drivers of tree-mortality events have been described for some beetle species (e.g., mountain pine beetle or spruce beetle) and their hosts (lodgepole pine and Engelmann spruce), less is known about how drivers at different scales interact to kill subalpine fir (Abies lasiocarpa) in a phenomenon simply dubbed "subalpine fir mortality" or "subalpine fir decline." Understanding the fate of subalpine fir is important, however, because this is commonly the tree species expected to establish and exhibit growth releases following outbreaks of mountain pine beetle or spruce beetle. In this study, we use three decades of field and remote data that span spatial scales from individual trees to sub-continental ecoregions to explore factors associated with subalpine fir mortality and how drivers interact across scales. Between 1991 and 2015, >5 million hectares (ha) of subalpine forest in the US Rocky Mountains have been affected by subalpine fir mortality. At the eco-region scale (1,000s of km), mortality was temporally associated with increases in regional drought stress, suggesting that climate is an important broad-scale driver. However, at the eco-region, landscape, and stand scales (several km to sub ha), mortality was greatest in cooler/wetter topographic locations and in areas with greater pre-mortality subalpine fir dominance. Conversely, mortality was lowest for fir trees in warmer/drier topographic locations and in areas of lesser pre-mortality subalpine fir dominance. This suggests that topographically driven differences in stand structure drive mortality dynamics at meso-scales and moderate the broad-scale influence of climate. Finally, at the tree and tree-neighborhood scale

  15. Transmission of Leishmania in coffee plantations of Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Bruce Alexander

    2002-07-01

    Full Text Available Transmission of Leishmania was studied in 27 coffee plantations in the Brazilian State of Minas Gerais. Eighteen females and six males (11.6% of the people tested, aged between 7-65 gave a positive response to the Montenegro skin test. Awareness of sand flies based on the ability of respondents to identify the insects using up to seven predetermined characteristics was significantly greater among inhabitants of houses occupied by at least one Mn+ve individual. Five species of phlebotomine sand fly, including three suspected Leishmania vectors, were collected within plantations under three different cultivation systems. Four of these species i.e., Lu. fischeri (Pinto 1926, Lu. migonei (França 1920, Lu. misionensis (Castro 1959 and Lutzomyia whitmani (Antunes & Coutinho 1939 were collected in an organic plantation and the last of these was also present in the other two plantation types. The remaining species, Lu. intermedia (Lutz & Neiva 1912, was collected in plantations under both the "adensado" and "convencional" systems. The results of this study indicate that transmission of Leishmania to man in coffee-growing areas of Minas Gerais may involve phlebotomine sand flies that inhabit plantations.

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

    DEFF Research Database (Denmark)

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

    2014-01-01

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

  17. Limnological research in the deep southern subalpine lakes: synthesis, directions and perspectives

    Directory of Open Access Journals (Sweden)

    Nico Salmaso

    2010-06-01

    Full Text Available Based on a selection of 230 papers published during the last 15 years in international journals, the present work aims at evaluating the state of the art of limnological research in the deep southern subalpine lakes (DSL: Garda, Iseo, Como, Lugano and Maggiore. Historically, most of the limnological research was fostered by the need to find solutions to the problems connected with eutrophication and pollution. Many data are available on the thermal structure, algal nutrient concentrations and phytoplankton of the DSL, while other topics still remain more or less constrained to single lakes. Apart from this geographical bias, a number of aspects emerged from this synoptic view. Limnological research is still linked to the concept of scientific monitoring, while experimental studies and modelling are confined to specific niches; the integration of different disciplines is held back by the division of studies on different compartments; integration of studies and synoptic analyses at a macro regional scale have been carried out only for specific research areas. The DSL are increasingly threatened by new pressures (climatic change, excessive proliferation of toxic cyanobacteria, introduction of new species and new micropollutants and by the interactions among these new and old stressors. In this rapidly changing situation, the paper emphasises the need to define criteria to be used to distinguish research able to produce relevant results and predictive models, which are essential elements for an efficient management of water resources.

  18. Patch-Scale Effects of Equine Disturbance on Arthropod Assemblages and Vegetation Structure in Subalpine Wetlands

    Science.gov (United States)

    Holmquist, Jeffrey G.; Schmidt-Gengenbach, Jutta; Ballenger, Elizabeth A.

    2014-06-01

    Assessments of vertebrate disturbance to plant and animal assemblages often contrast grazed versus ungrazed meadows or other larger areas of usage, and this approach can be powerful. Random sampling of such habitats carries the potential, however, for smaller, more intensely affected patches to be missed and for other responses that are only revealed at smaller scales to also escape detection. We instead sampled arthropod assemblages and vegetation structure at the patch scale (400-900 m2 patches) within subalpine wet meadows of Yosemite National Park (USA), with the goal of determining if there were fine-scale differences in magnitude and directionality of response at three levels of grazing intensity. Effects were both stronger and more nuanced than effects evidenced by previous random sampling of paired grazed and ungrazed meadows: (a) greater negative effects on vegetation structure and fauna in heavily used patches, but (b) some positive effects on fauna in lightly grazed patches, suggested by trends for mean richness and total and population abundances. Although assessment of disturbance at either patch or landscape scales should be appropriate, depending on the management question at hand, our patch-scale work demonstrated that there can be strong local effects on the ecology of these wetlands that may not be detected by comparing larger scale habitats.

  19. A molecular investigation of soil organic carbon composition across a subalpine catchment

    Science.gov (United States)

    Hsu, Hsiao-Tieh; Lawrence, Corey R.; Winnick, Matthew J.; Bargar, John R.; Maher, Katharine

    2018-01-01

    The dynamics of soil organic carbon (SOC) storage and turnover are a critical component of the global carbon cycle. Mechanistic models seeking to represent these complex dynamics require detailed SOC compositions, which are currently difficult to characterize quantitatively. Here, we address this challenge by using a novel approach that combines Fourier transform infrared spectroscopy (FT-IR) and bulk carbon X-ray absorption spectroscopy (XAS) to determine the abundance of SOC functional groups, using elemental analysis (EA) to constrain the total amount of SOC. We used this SOC functional group abundance (SOC-fga) method to compare variability in SOC compositions as a function of depth across a subalpine watershed (East River, Colorado, USA) and found a large degree of variability in SOC functional group abundances between sites at different elevations. Soils at a lower elevation are predominantly composed of polysaccharides, while soils at a higher elevation have more substantial portions of carbonyl, phenolic, or aromatic carbon. We discuss the potential drivers of differences in SOC composition between these sites, including vegetation inputs, internal processing and losses, and elevation-driven environmental factors. Although numerical models would facilitate the understanding and evaluation of the observed SOC distributions, quantitative and meaningful measurements of SOC molecular compositions are required to guide such models. Comparison among commonly used characterization techniques on shared reference materials is a critical next step for advancing our understanding of the complex processes controlling SOC compositions.

  20. Phytoplankton association patterns in the deep southern subalpine lakes (Part 2

    Directory of Open Access Journals (Sweden)

    Nico Salmaso

    2003-08-01

    Full Text Available The three following papers constitute the second, and final, part of a series of papers dedicated to the phytoplankton of the deep subalpine Italian lakes (DSL. The first part, comprising an introduction and three papers on lakes Garda, Como and Maggiore respectively, was published in the volume 61 (1 of this journal (J. Limnol., 61. The research, carried out for three years (two years in L.Como in the period 1997-2000, was a concerted effort by investigators of five Insitutes in Italy and Switzerland. It was generated by the awareness that, despite the large number of papers existing on the phytoplankton of the single DSL, those of a comprehensive nature are very few, and by the perceived interest of a comparative investigation on the phytoplankton of the large lakes in the Insubrian district in the light of the recent progress on the ecology of the freshwater algae. So, in the final paper following those on lakes Iseo and Lugano an effort is made to compare and characterize the different species assemblages in the background of geographical and morphological characteristics, and of recent changes in trophic gradients. Despite often important differences in these respects, and observed various community responses, a common pool of species seems to be identifiable in the district.

  1. Development of partial rock veneers by root throw in a subalpine setting

    Science.gov (United States)

    Osterkamp, W.R.; Toy, T.J.; Lenart, M.T.

    2006-01-01

    Rock veneers stabilize hillslope surfaces, occur especially in areas of immature soil, and form through a variety of process sets that includes root throw. Near Westcliffe, Colorado, USA, data were collected from a 20 ?? 500 m transect on the east slope of the Sangre de Cristo Mountains. Ages of pit/mound complexes with rock fragments exposed at the surface by root throw ranged from recent (freshly toppled tree) to unknown (complete tree decay). Calculations based on dimensions of the pit/mound complexes, estimated time of free topppling, sizes of exposed rock fragments, and percentage rock covers at pit/mound complexes, as well as within the transect area, indicate that recent rates of root throw have resulted in only partial rock veneering since late Pleistocene deglaciation. Weathering of rock fragments prevent development of an extensive rock veneer and causes a balance, achieved within an estimated 700 years, between the rates of rock-fragment exposure by root throw and clast disintegration by chemical reduction. The estimated rate of rock-fragment reduction accounts for part of the fluvial sediment yields observed for forested subalpine areas of western North America. Copyright ?? 2005 John Wiley & Sons, Ltd.

  2. Targeted grazing for the restoration of sub-alpine shrub-encroached grasslands

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    Massimiliano Probo

    2016-12-01

    Full Text Available The decline of agro-pastoral activities has led to a widespread tree and shrub-encroachment of former semi-natural meso-eutrophic grasslands in many European mountain regions. Temporary night camp areas (TNCA and mineral mix supplements for targeted cattle were arranged over shrub-encroached areas to restore grassland vegetation within the Val Troncea Natural Park (Italy. From 2011 to 2015, their effects on vegetation structure and pastoral value of forage were assessed along permanent transects. Four years after treatments, both practices were effective in reducing the shrub cover and increasing the cover and average height of the herbaceous layer, but changes were more remarkable within TNCA. Moreover, the arrangement of TNCA decreased the cover of nanophanerophytes and increased the cover of graminoids and high quality species, as well as the overall forage pastoral value. In conclusion, TNCA were the most effective pastoral practice to contrast shrub-encroachment and increase herbage mass and forage quality of sub-alpine grasslands.

  3. Extensive wildfires, climate change, and an abrupt state change in subalpine ribbon forests, Colorado.

    Science.gov (United States)

    Calder, W John; Shuman, Bryan

    2017-10-01

    Ecosystems may shift abruptly when the effects of climate change and disturbance interact, and landscapes with regularly patterned vegetation may be especially vulnerable to abrupt shifts. Here we use a fossil pollen record from a regularly patterned ribbon forest (alternating bands of forests and meadows) in Colorado to examine whether past changes in wildfire and climate produced abrupt vegetation shifts. Comparing the percentages of conifer pollen with sedimentary δ18 O data (interpreted as an indicator of temperature or snow accumulation) indicates a first-order linear relationship between vegetation composition and climate change with no detectable lags over the past 2,500 yr (r = 0.55, P changed abruptly within a century of extensive wildfires, which were recognized in a previous study to have burned approximately 80% of the surrounding 1,000 km2 landscape 1,000 yr ago when temperatures rose ~0.5°C. The vegetation change was larger than expected from the effects of climate change alone. Pollen assemblages changed from a composition associated with closed subalpine forests to one similar to modern ribbon forests. Fossil pollen assemblages then remained like those from modern ribbon forests for the following ~1,000 yr, providing a clear example of how extensive disturbances can trigger persistent new vegetation states and alter how vegetation responds to climate. © 2017 by the Ecological Society of America.

  4. Litter Production, Decomposition, and Nutrient Release in Subalpine Forest Communities of the Northwest Himalaya

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    Vinod K. Bisht

    2014-01-01

    Full Text Available Production, decomposition, and release of nutrients from leaf and nonleaf litter were investigated in four subalpine forests of North-West Himalaya, India. Total annual litter fall in four communities varied from 2950.00 to 4040.00 kg ha−1 and was found significant (CD0.05 = 118.2. Decomposition of leaf litter varied from 1.82–3.5% during autumn-winter to 36.14–45.51 during summer rainy season in all stands and percent of mass loss was significantly varied in stands (CD6.00. Similarly, decomposition in nonleaf litter was varied from 0.3–1.1% during autumn-winter to 19.59–30.05% during summer rainy season and was significantly varied irrespective of seasons. However, percent decomposition of leaf litter and the values of decay constant (k were at par in all stands. Total standing state of nutrients in fresh litter as well as release of total nitrogen (N, phosphorus (P, and potassium (K in due course of decomposition (12 months was also varying significantly. The rate of nonleaf litter decomposition was significantly positively correlated with air temperature (r=0.63–0.74 in all communities. The significant correlation (r=0.85 was observed only in Rhododendron-Sorbus forest community (PRS. Study indicates that the air temperature is a major determinant for nonleaf litter decomposition in this region.

  5. Does the aboveground herbivore assemblage influence soil bacterial community composition and richness in subalpine grasslands?

    Science.gov (United States)

    Hodel, Melanie; Schütz, Martin; Vandegehuchte, Martijn L; Frey, Beat; Albrecht, Matthias; Busse, Matt D; Risch, Anita C

    2014-10-01

    Grassland ecosystems support large communities of aboveground herbivores that are known to directly and indirectly affect belowground properties such as the microbial community composition, richness, or biomass. Even though multiple species of functionally different herbivores coexist in grassland ecosystems, most studies have only considered the impact of a single group, i.e., large ungulates (mostly domestic livestock) on microbial communities. Thus, we investigated how the exclusion of four groups of functionally different herbivores affects bacterial community composition, richness, and biomass in two vegetation types with different grazing histories. We progressively excluded large, medium, and small mammals as well as invertebrate herbivores using exclosures at 18 subalpine grassland sites (9 per vegetation type). We assessed the bacterial community composition using terminal restriction fragment length polymorphism (T-RFLP) at each site and exclosure type during three consecutive growing seasons (2009-2011) for rhizosphere and mineral soil separately. In addition, we determined microbial biomass carbon (MBC), root biomass, plant carbon:nitrogen ratio, soil temperature, and soil moisture. Even though several of these variables were affected by herbivore exclusion and vegetation type, against our expectations, bacterial community composition, richness, or MBC were not. Yet, bacterial communities strongly differed between the three growing seasons as well as to some extent between our study sites. Thus, our study indicates that the spatiotemporal variability in soil microclimate has much stronger effects on the soil bacterial communities than the grazing regime or the composition of the vegetation in this high-elevation ecosystem.

  6. Do insects lose flight before they lose their wings? Population genetic structure in subalpine stoneflies.

    Science.gov (United States)

    McCulloch, Graham A; Wallis, Graham P; Waters, Jonathan M

    2009-10-01

    Wing reduction and flightlessness are common features of alpine and subalpine insects, and are typically interpreted as evolutionary adaptations to increase fecundity and promote local recruitment. Here, we assess the impact of wing reduction on dispersal in stoneflies (Plecoptera: Gripopterygidae: Zelandoperla) in southern New Zealand. Specifically, we present comparative phylogeographic analyses (COI; H3) of strong-flying Zelandoperla decorata (144 individuals, 63 localities) vs. the co-distributed but weak-flying Zelandoperla fenestrata species group (186 individuals, 81 localities). The latter group exhibits a variety of morphotypes, ranging from fully winged to completely wingless. Consistent with its capacity for strong flight-mediated dispersal, Z. decorata exhibited no substantial phylogeographic differentiation across its broad South Island range. Conversely the weak-flying fenestrata species group exhibited substantial genetic structure across both fine and broad geographic scales. Intriguingly, the variable degrees of wing development observed within the fenestrata species group had no apparent impact on levels of phylogeographic structure, which were high regardless of morphotype, suggesting that even fully winged specimens of this group do not fly. This finding implies that Zelandoperla flight loss occurs independently of wing loss, and might reflect underlying flight muscle reduction.

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

    Directory of Open Access Journals (Sweden)

    Jeanne Portier

    2016-09-01

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

  8. Effects of elevated nitrogen deposition on the field-layer vegetation in coniferous forests

    Energy Technology Data Exchange (ETDEWEB)

    Kellner, O. [Swedish Univ. of Agricultural Science, Dept. of Ecology and Enviromental Research, Uppsala (Sweden); Redbo-Torstensson, P. [Uppsala Univ., Dept. of Ecological Botany, Uppsala (Sweden)

    1995-12-31

    Time series studies on vegetation changes in European coniferous forests are reviewed in relation to nitrogen deposition. In areas with high N deposition, grasses had increased together with mean indicator values for nitrogen. The same type of changes have been recorded in nitrogen fertilization experiments. In order to investigate whether such vegetation changes only take place at high N deposition levels, we performed a five-year experiment in which nitrogen was applied to the field layer in a coniferous forest in central Sweden. There were five different fertilization treatments: i) control with no extra nitrogen, ii) 0.5, iii) 1.0, iv) 2.0, and v) 4.0 g N m{sup -2} yr{sup -1}. Six species were present in sufficient amounts to make analyses of changes possible: Deschampsia flexuosa, Linnaea borealis, luzula pilosa, Trientalis europaea, Vaccinium myrtillus and V. vitis-idaea. for only two of these species (D. flexuosa and T. europaea) was there a significant effect of the nitrogen treatment. A third species (V. myrtillus) changed significantly through the years, but showed no effect of nitrogen. For D. fluxuosa, the magnitude of the increase in shoot density after five years was closely related to the amount of nitrogen added. In control plots it shoot density remained fairly constant. Ramet density of T. europaea more than doubled in the two treatments with the lowest amounts of added nitrogen, and increased more than five times in the two highest treatments. In the control treatment ramet density was fairly constant. Vaccinium myrtillus increased in density during the five years, from 36 ramets m{sup -2} in 1988 to 46 m{sup -2} 1992. The increase in ramet density was observed in all treatments and we detected no significant effect of nitrogen treatments. Our results indicate that changes in the field layer are induced already at low deposition rates (0.5 g N m{sup - }yr{sup -1} in through-fall). (Abstract Truncated)

  9. Antimicrobial properties of natural coniferous rosin in the European Pharmacopoeia challenge test.

    Science.gov (United States)

    Sipponen, Arno; Laitinen, Kirsi

    2011-10-01

    Rosins (resins) are natural products of the coniferous trees. Purified rosin from the trunk of Norway spruce (Picea abies) is antibacterial against the gram-positive bacteria, but not against the gram-negative bacteria in agar plate diffusion test. In this study, we examined the antimicrobial properties of the coniferous rosin against bacteria and yeasts using the European Pharmacopoeia (EP) challenge test. The microbes tested were Staphylococcus aureus, methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Candida albicans. To prepare challenge media, purified rosin was mixed with a biologically inert salve in varying concentrations. The microbes were inoculated (5 × 10(5) microbes (bacteria) or 5 × 10(4) microbes (yeast, C.albicans)) into 10 g of the rosin-containing challenge medium for 14 days at maximum. Samples were taken from the media for re-cultivation of the microbes at time intervals of 1 h, 24 h, 4, 7, and 14 days. The microbicidal efficacy of the challenge media was estimated by reduction of the number of the colony forming units (CFU) of microbes in the test samples. A reduction of more than 10(3) CFU for bacteria and 10(2) CFU for fungi in 7 days was considered to indicate a significant microbicidal action. Pure rosin was antimicrobial within 24 h against all microbes tested. The 0.5% rosin-salve medium (w/w) did not differ in microbicidal effects from the rosin-free salve medium (control). A raise of the rosin concentration resulted in increase of the microbicidal effect of the rosin-salve medium against all micro-organisms tested. Rosin concentration of 10% (w/w) in the medium significantly reduced the colonization of S. aureus (including MRSA) within 24 h and significantly reduced the colonization of all other micro-organisms within 4 days. Rosin is strongly microbicidal against a wide range of microbes, against both gram-positive and gram-negative bacteria, and against C. albicans

  10. Of peasants, plantations, and immigrant proletarians

    Directory of Open Access Journals (Sweden)

    Samuel Martí­nez

    1993-01-01

    Full Text Available [First paragraph] Dominican Sugar Plantations: Production and Foreign Labor Integration. MARTIN F. MURPHY. New York: Praeger, 1991. xii + 186 pp. (Cloth US$49.95 Peasants in Distress: Poverty and Unemployment in the Dominican Republic. ROSEMARY VARGAS-LUNDIUS. Boulder CO: Westview 1991. xxi + 387 pp. (Paper US$ 32.95 Few other places in the Caribbean region have as great a potential for international conflict as the island of Hispaniola. The historical antagonism between Haiti and the Dominican Republic is no doubt known to readers of this journal, as is the recent upsurge in tension between the two countries, which culminated in the expulsion of tens of thousands of Haitian immigrants from the Dominican Republic, from June to September 1991. The quickening pace of events, added to the worsening spiral of economic hardship gripping both nations, threaten to render obsolete even the most recent analyses of relations between the two countries. Even so, against the background of an increasingly acrimonious debate between the Dominican government and international human rights organizations accusing it of enslaving Haitian immigrants in the cane flelds, the appearance of two works by long-time students of the migration of Haitians as cane workers to the Dominican Republic is particularly timely.

  11. Rejuvenated sycamore cuttings for energy plantations

    Energy Technology Data Exchange (ETDEWEB)

    Land, S.B. Jr.; Elam, W.W. [Mississippi State Univ., MS (United States). Dept. of Forestry; Khan, Mohammad [Pakistan Forest Inst., Peshawar (Pakistan). Forestry Research Div.

    1995-12-31

    Rejuvination of mature, progeny tested American sycamore trees is needed to increase rooting success of cuttings for energy plantations. Studies conducted in Mississippi (U.S.A.) indicated that hedging of stock plants and spraying the stock plants with benzyl adenine may rejuvinate the cuttings. Percentages of cuttings with early bud break in one study and with sprouts and roots after nine months in another study were increased. The rooted cuttings grew rapidly like juvenile material and showed no plagiotrophic effects during the first year after transplanting. At the end of that year the dry weight was 2.13 Mg ha{sup -1} (1.2 m x 3.6 m spacing) and was distributed in stems (31%), branches (14%), leaves (24%) and roots (31%). An IBA rooting powder decreased rooting success. Planting cuttings directly in the nursery, rather than first in the greenhouse, increased success when frost was absent. Use of cuttings of greater than 14 m diameter with a node within 2 cm of the base increased success. Clonal differences in frost susceptibility of sprouting cuttings were observed. (author)

  12. Comparative analysis of lignin peroxidase and manganese peroxidase activity on coniferous and deciduous wood using ToF-SIMS.

    Science.gov (United States)

    MacDonald, Jacqueline; Goacher, Robyn E; Abou-Zaid, Mamdouh; Master, Emma R

    2016-09-01

    White-rot fungi are distinguished by their ability to efficiently degrade lignin via lignin-modifying type II peroxidases, including manganese peroxidase (MnP) and lignin peroxidase (LiP). In the present study, time-of flight secondary ion mass spectrometry (ToF-SIMS) was used to evaluate lignin modification in three coniferous and three deciduous wood preparations following treatment with commercial preparations of LiP and MnP from two different white-rot fungi. Percent modification of lignin was calculated as a loss of intact methoxylated lignin over nonfunctionalized aromatic rings, which is consistent with oxidative cleavage of methoxy moieties within the lignin structure. Exposure to MnP resulted in greater modification of lignin in coniferous compared to deciduous wood (28 vs. 18 % modification of lignin); and greater modification of G-lignin compared to S-lignin within the deciduous wood samples (21 vs. 12 %). In contrast, exposure to LiP resulted in similar percent modification of lignin in all wood samples (21 vs 22 %), and of G- and S-lignin within the deciduous wood (22 vs. 23 %). These findings suggest that the selected MnP and LiP may particularly benefit delignification of coniferous and deciduous wood, respectively. Moreover, the current analysis further demonstrates the utility of ToF-SIMS for characterizing enzymatic modification of lignin in wood fibre along with potential advantages over UV and HPCL-MS detection of solubilized delignification products.

  13. Comparison of the Profile and Composition of Volatiles in Coniferous Needles According to Extraction Methods

    Directory of Open Access Journals (Sweden)

    Yonjin Jun

    2016-03-01

    Full Text Available The enantiomeric distribution and profile of volatiles in plants, which affect the biological and organoleptic properties, can be varied depending on extraction methods as well as their cultivars. The secondary volatile components of the needles of three conifer cultivars (Chamaecyparispisifera, Chamaecyparisobtusa, and Thujaorientalis were compared. Furthermore, the effects of three different extraction methods—solid-phase microextraction (SPME, steam distillation (SD, and solvent extraction (SE—on the composition and enantiomeric distribution of those volatiles were elucidated. Monoterpene hydrocarbons predominated in all samples, and the compositions of sesquiterpenes and diterpenes differed according to the cultivar. In particular, the yields of oxygenated monoterpenes and sesquiterpenes were greatest for SD, whereas those of sesquiterpenes and diterpenes were highest for SE. On the other hand, more monoterpenes with higher volatility could be obtained with SPME and SD than when using SE. In addition, the enantiomeric composition of nine chiral compounds found in three cultivars differed according to their chemotype. There were also some differences in the yielded oxygenated monoterpenes and sesquiterpene hydrocarbons, but not monoterpene hydrocarbons, according to the extraction method. These results demonstrate that the extraction methods used as well as the cultivars influence the measured volatile profiles and enantiomeric distribution of coniferous needle extracts.

  14. MLAOS: A Multi-Point Linear Array of Optical Sensors for Coniferous Foliage Clumping Index Measurement

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    Yonghua Qu

    2014-05-01

    Full Text Available The canopy foliage clumping effect is primarily caused by the non-random distribution of canopy foliage. Currently, measurements of clumping index (CI by handheld instruments is typically time- and labor-intensive. We propose a low-cost and low-power automatic measurement system called Multi-point Linear Array of Optical Sensors (MLAOS, which consists of three above-canopy and nine below-canopy optical sensors that capture plant transmittance at different times of the day. Data communication between the MLAOS node is facilitated by using a ZigBee network, and the data are transmitted from the field MLAOS to a remote data server using the Internet. The choice of the electronic element and design of the MLAOS software is aimed at reducing costs and power consumption. A power consumption test showed that, when a 4000 mAH Li-ion battery is used, a maximum of 8–10 months of work can be achieved. A field experiment on a coniferous forest revealed that the CI of MLAOS may reveal a clumping effect that occurs within the canopy. In further work, measurement of the multi-scale clumping effect can be achieved by utilizing a greater number of MLAOS devices to capture the heterogeneity of the plant canopy.

  15. Nitrous oxide uptake rates in boreal coniferous forests are associated with soil characteristics

    Science.gov (United States)

    Siljanen, Henri; Biasi, Christina; Martikainen, Pertti

    2014-05-01

    Nitrous oxide (N2O) is a strong greenhouse gas and a significant contributor to the destruction of the ozone layer. The radiative forcing of N2O is considered to be 320 more efficient than carbon dioxide.The major portion of global N2O is emitted from agricultural soils. There are studies suggesting that N2O has also a sink in forest soils. However there is relatively limited knowledge on factors controlling N2O consumption in forest soils. Hence N2O consumption was studied in boreal coniferous forests having different forest cover, soil chemical and physical structure and land-use history. The N2O consumption was measured by static chamber technique in the field across spatio-seasonal sampling design. Typical and atypical denitrifiers were quantified with nosZ functional gene marker. Additionally chemical and physical environmental parameters were analyzed to link N2O flux, microbial community and composition of soils. Nitrous oxide uptake could be associated with specific ecosystem and environmental conditions. Soil physical structure and land-use history were shown to be prior factors determining the strength of the uptake rate.

  16. Economically and ecologically important plant communities in high altitude coniferous forest of Malam Jabba, Swat, Pakistan.

    Science.gov (United States)

    Sher, Hassan; Al Yemeni, Mohammad

    2011-01-01

    A study on the economically important plant communities was carried out during summer 2008 in various parts of Malam Jabba valley, Swat. The principal aim of the study was phytosociological evaluation with special reference to the occurrence of commercially important medicinal plant species in coniferous forest of the study area. Secondly to prepare ethnobotanical inventory of the plant resources of the area, as well as to evaluate the conservation status of important medicinal and aromatic plants (MAPs) through rapid vulnerable assessment (RVA) procedure. The study documented 90 species of ethnobotanical importance, out of these 71 spp used as medicinal plant, 20 spp fodder plant, 10 spp vegetables, 14 spp wild fruit, 18 spp fuel wood, 9 spp furniture and agricultural tools, 9 spp thatching, fencing and hedges, 4 spp honey bee, 2 spp evil eyes, 2 spp religious and 3 spp as poison. Phytosociologically six plant communities were found, comprising five herbs-shrubs-trees communities and one meadow community. Further study is, therefore, required to quantify the availability of species and to suggest suitable method for their production and conservation. Recommendations are also given in the spheres of training in identification, sustainable collection, value addition, trade monitoring and cooperative system of marketing.

  17. Impacts of simulated herbivory on VOC emission profiles from coniferous plants

    Science.gov (United States)

    Faiola, C. L.; Jobson, B. T.; VanReken, T. M.

    2014-09-01

    The largest global source of volatile organic compounds (VOCs) in the atmosphere is from biogenic emissions. Plant stressors associated with a changing environment can alter both the quantity and composition of the compounds that are emitted. This study investigated the effects of one global change stressor, increased herbivory, on plant emissions from five different coniferous species: bristlecone pine (Pinus aristata), blue spruce (Picea pungens), western redcedar (Thuja plicata), grand fir (Abies grandis), and Douglas-fir (Pseudotsugas menziesii). Herbivory was simulated in the laboratory via exogenous application of methyl jasmonate, an herbivory proxy. Gas-phase species were measured continuously with a gas chromatograph coupled to a mass spectrometer and flame ionization detector (GC-MS-FID). Stress responses varied between the different plant types and even between experiments using the same set of saplings. The compounds most frequently impacted by the stress treatment were alpha-pinene, beta-pinene, 1,8-cineol, beta-myrcene, terpinolene, limonene, and the cymene isomers. Individual compounds within a single experiment often exhibited a different response to the treatment from one another.

  18. Impacts of simulated herbivory on volatile organic compound emission profiles from coniferous plants

    Science.gov (United States)

    Faiola, C. L.; Jobson, B. T.; VanReken, T. M.

    2015-01-01

    The largest global source of volatile organic compounds (VOCs) in the atmosphere is from biogenic emissions. Plant stressors associated with a changing environment can alter both the quantity and composition of the compounds that are emitted. This study investigated the effects of one global change stressor, increased herbivory, on plant emissions from five different coniferous species: bristlecone pine (Pinus aristata), blue spruce (Picea pungens), western redcedar (Thuja plicata), grand fir (Abies grandis), and Douglas-fir (Pseudotsuga menziesii). Herbivory was simulated in the laboratory via exogenous application of methyl jasmonate (MeJA), a herbivory proxy. Gas-phase species were measured continuously with a gas chromatograph coupled to a mass spectrometer and flame ionization detector (GC-MS-FID). Stress responses varied between the different plant types and even between experiments using the same set of saplings. The compounds most frequently impacted by the stress treatment were alpha-pinene, beta-pinene, 1,8-cineol, beta-myrcene, terpinolene, limonene, and the cymene isomers. Individual compounds within a single experiment often exhibited a different response to the treatment from one another.

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

    Directory of Open Access Journals (Sweden)

    N. K. Kozhevnikova

    2017-06-01

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

  20. Studies on adsorption of crystal violet dye from aqueous solution onto coniferous pinus bark powder (CPBP)

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Rais, E-mail: rais45@rediffmail.com [Environmental Research Laboratory, Department of Applied Chemistry, Faculty of Engineering and Technology, Aligarh Muslim University, Aligarh 202002, UP (India)

    2009-11-15

    The present study shows that the coniferous pinus bark powder (CPBP) can be used as a potential adsorbent for the removal of crystal violet (basic dye) from aqueous solutions. Experiments were carried out as a function of contact time, concentration, temperature, pH and dosage. The amount of dye uptake was found to vary with increasing initial solution pH and maximum adsorption was observed at pH 8. The equilibrium was attained in 2 h. The amount of dye uptake (mg/g) was found to increase with increase in dye concentration and contact time. The % adsorption was found to decrease with increase in amount of adsorbent. The thermodynamic parameters were also calculated and the positive value of {Delta}H{sup o} indicates the endothermic nature of adsorption. The applicability of the three isotherm's model for the present data follows the order: Langmuir > Temkin > Freundlich. The kinetics of crystal violet on to the adsorbent can be described well by pseudo-second order > Elovich > pseudo-first order equation.

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

    Science.gov (United States)

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

    2018-01-01

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

  2. Long-term reactive nitrogen loading alters soil carbon and microbial community properties in a subalpine forest ecosystem

    Science.gov (United States)

    Boot, Claudia M; Hall, Ed K.; Denef, Karolien; Baron, Jill S.

    2016-01-01

    Elevated nitrogen (N) deposition due to increased fossil fuel combustion and agricultural practices has altered global carbon (C) cycling. Additions of reactive N to N-limited environments are typically accompanied by increases in plant biomass. Soil C dynamics, however, have shown a range of different responses to the addition of reactive N that seem to be ecosystem dependent. We evaluated the effect of N amendments on biogeochemical characteristics and microbial responses of subalpine forest organic soils in order to develop a mechanistic understanding of how soils are affected by N amendments in subalpine ecosystems. We measured a suite of responses across three years (2011–2013) during two seasons (spring and fall). Following 17 years of N amendments, fertilized soils were more acidic (control mean 5.09, fertilized mean 4.68), and had lower %C (control mean 33.7% C, fertilized mean 29.8% C) and microbial biomass C by 22% relative to control plots. Shifts in biogeochemical properties in fertilized plots were associated with an altered microbial community driven by reduced arbuscular mycorrhizal (control mean 3.2 mol%, fertilized mean 2.5 mol%) and saprotrophic fungal groups (control mean 17.0 mol%, fertilized mean 15.2 mol%), as well as a decrease in N degrading microbial enzyme activity. Our results suggest that decreases in soil C in subalpine forests were in part driven by increased microbial degradation of soil organic matter and reduced inputs to soil organic matter in the form of microbial biomass.

  3. Trace elements in sub-alpine forest soils on the eastern edge of the Tibetan Plateau, China

    Science.gov (United States)

    Wang, Xiaodan; Cheng, Genwei; Zhong, Xianghao; Li, Mai-He

    2009-08-01

    Industrial development has increased fast in China during the last decades. This has led to a range of environmental problems. Deposition of trace elements to forest ecosystems via the atmosphere is one potential problem. In this paper, we report the results from a pilot study where the trace element levels of the sub-alpine forest soils on the eastern edge of the Tibetan Plateau have been measured. Possible relationships between soil properties and trace element concentrations have also been investigated. The obtained concentrations (mg kg-1) were boron (B) 48.06-53.70, molybdenum (Mo) 1.53-2.26, zinc (Zn) 68.18-79.53, copper (Cu) 36.81-42.44, selenium (Se) 0.33-0.49, cadmium (Cd) 0.16-0.29, lead (Pb) 25.80-30.71, chromium (Cr) 96.10-110.08, nickel (Ni) 30.16-45.60, mercury (Hg) 0.05-0.11, and arsenic (As) 3.09-4.17. With a few exceptions, the element concentration can be characterized as low in the investigated sub-alpine forest soils. No clear differences in trace element levels were found between topsoil and subsoil samples, indicating that the atmospheric deposition of trace element has been low. The soil parent material plays a key role to determine trace element levels. Soil properties, including pHw, organic carbon (OC), clay fraction, cation-exchange capacity (CEC), total iron (Fe), and total aluminum (Al) concentrations were related to trace element concentration using correlation analysis. Total Fe and Al showed the strongest relationships with concentrations of most trace elements in the sub-alpine forest soils. PCA analyses indicated that a significant increase in the number of cars with the fast development of local tourism may result in higher Pb concentration in the future.

  4. Assessing heat fluxes and water quality trends in subalpine lakes from EO

    Science.gov (United States)

    Cazzaniga, Ilaria; Giardino, Claudia; Bresciani, Mariano; Elli, Chiara; Valerio, Giulia; Pilotti, Marco

    2017-04-01

    Lakes play a fundamental role in providing ecosystem services such as water supplying, hydrological regulation, climate change mitigation, touristic recreation (Schallenberg et al., 2013). Preserving and improving of quality of lakes waters, which is a function of either both natural and human influences, is therefore an important action to be considered. Remote Sensing techniques are spreading as useful instrument for lakes, by integrating classical in situ limnological measurements to frequent and synoptic monitoring capabilities. Within this study, Earth Observation data are exploited for understanding the temporal changes of water quality parameters over a decade, as well as for measuring the surface energy fluxes in recent years in deep clear lakes in the European subalpine ecoregion. According to Pareth et al. (2016), subalpine lakes are showing a clear response to climate change with an increase of 0.017 °C /year of lake surface temperature, whilst the human activities contribute to produce a large impact (agriculture, recreation, industry, fishing and drinking) on these lakes. The investigation is focused on Lake Iseo, which has shown a significant deterioration of water quality conditions since the seventies, and on Lake Garda, the largest Italian lake where EO data have been widely used for many purposes and applications (Giardino et al., 2014). Available ENVISAT-MERIS (2002-2012) and Landsat-8-OLI (2013-on going) imagery has been exploited to produce chlorophyll-a (chl-a) concentration maps, while Landsat-8-TIRS imagery has been used for estimating lake surface temperatures. MERIS images were processed through a neural network (namely the C2R processor, Doerffer et al., 2007), to correct the atmospheric effects and to retrieve water constituents concentration in optically complex deep waters. With regard to L8's images, some atmospheric correctors (e.g. ACOLITE and 6SV) were tested and validated to indentify, for each of the two lakes, the more accurate

  5. Fire effects in Pinus uncinata Ram plantations

    Directory of Open Access Journals (Sweden)

    Adrián Cardil Forradellas

    2016-04-01

    Full Text Available Aim of study: Understanding fire ecology of main forest species is essential for a sound, scientifically based on managing of wildlands and also to assess likely implications due to changes in fire regime under a global change scenario. Few references can be found about fire ecology of Pinus uncinata Ram. (PU. PU species grows in the Central Pyrenees where large, severe wildland fires did not occur frequently in the past. However, several fires with extreme fire behavior have affected PU stands in last years and they might disturb other PU forest in the future.Area of study: Cabdella fire (February 2012, in Lleida province, is one of the several wildland fires occurred in 2012 (winter season in the Central Pyrenees. Fire affected a large PU plantation (102 ha located at 1.800-2,100 meters above the sea.Material and methods: We have analyzed first order fire effects in three fireline intensity thresholds along three years in terms of mortality ratio, scorched height, percentage of scorched crown volume and bark char height.Main results: PU seems to be a very tolerant species to low and medium fire line intensity but fire effects were very significant when fire line intensity was high. In medium fireline intensity sites, probability of mortality ranged from 15 to 30% and the dead trees had the highest values on scorched height and percentage of scorched crown volume.Research highlights: Results from this work supports that prescribed burning might be used to efficiently decrease fuel load and fuel vertical continuity while avoiding considerable PU mortality. It also displayed that when fuel management has been implemented, PU mortality might be limited even under extreme fire behavior.Abbreviations used: PU: Pinus uncinata Ram.

  6. Fire effects in Pinus uncinata Ram plantations

    Energy Technology Data Exchange (ETDEWEB)

    Cardil Forradellas, A.; Molina Terrén, D.M.; Oliveres, J.; Castellnou, M.

    2016-07-01

    Aim of study: Understanding fire ecology of main forest species is essential for a sound, scientifically based on managing of wildlands and also to assess likely implications due to changes in fire regime under a global change scenario. Few references can be found about fire ecology of Pinus uncinata Ram. (PU). PU species grows in the Central Pyrenees where large, severe wildland fires did not occur frequently in the past. However, several fires with extreme fire behavior have affected PU stands in last years and they might disturb other PU forest in the future. Area of study: Cabdella fire (February 2012), in Lleida province, is one of the several wildland fires occurred in 2012 (winter season) in the Central Pyrenees. Fire affected a large PU plantation (102 ha) located at 1.800-2,100 meters above the sea. Material and methods: We have analyzed first order fire effects in three fireline intensity thresholds along three years in terms of mortality ratio, scorched height, percentage of scorched crown volume and bark char height. Main results: PU seems to be a very tolerant species to low and medium fire line intensity but fire effects were very significant when fire line intensity was high. In medium fireline intensity sites, probability of mortality ranged from 15 to 30% and the dead trees had the highest values on scorched height and percentage of scorched crown volume. Research highlights: Results from this work supports that prescribed burning might be used to efficiently decrease fuel load and fuel vertical continuity while avoiding considerable PU mortality. It also displayed that when fuel management has been implemented, PU mortality might be limited even under extreme fire behavior. (Author)

  7. Is spatial structure the key to promote plant diversity in Mediterranean forets plantations?

    NARCIS (Netherlands)

    González-Moreno, P.; Quero, J.L.; Poorter, L.; Bonet, F.J.; Zamora, R.

    2011-01-01

    Mediterranean forest plantations are currently under an intense debate related to their ecological function, sustainability and future performance. In several Mediterranean countries, efforts are directed to convert pine plantations into mixed and more diverse forests. This research aims to evaluate

  8. Hydrologic flow path development varies by aspect during spring snowmelt in complex subalpine terrain

    Science.gov (United States)

    Webb, Ryan W.; Fassnacht, Steven R.; Gooseff, Michael N.

    2018-01-01

    In many mountainous regions around the world, snow and soil moisture are key components of the hydrologic cycle. Preferential flow paths of snowmelt water through snow have been known to occur for years with few studies observing the effect on soil moisture. In this study, statistical analysis of the topographical and hydrological controls on the spatiotemporal variability of snow water equivalent (SWE) and soil moisture during snowmelt was undertaken at a subalpine forested setting with north, south, and flat aspects as a seasonally persistent snowpack melts. We investigated if evidence of preferential flow paths in snow can be observed and the effect on soil moisture through measurements of snow water equivalent and near-surface soil moisture, observing how SWE and near-surface soil moisture vary on hillslopes relative to the toes of hillslopes and flat areas. We then compared snowmelt infiltration beyond the near-surface soil between flat and sloping terrain during the entire snowmelt season using soil moisture sensor profiles. This study was conducted during varying snowmelt seasons representing above-normal, relatively normal, and below-normal snow seasons in northern Colorado. Evidence is presented of preferential meltwater flow paths at the snow-soil interface on the north-facing slope causing increases in SWE downslope and less infiltration into the soil at 20 cm depth; less association is observed in the near-surface soil moisture (top 7 cm). We present a conceptualization of the meltwater flow paths that develop based on slope aspect and soil properties. The resulting flow paths are shown to divert at least 4 % of snowmelt laterally, accumulating along the length of the slope, to increase the snow water equivalent by as much as 170 % at the base of a north-facing hillslope. Results from this study show that snow acts as an extension of the vadose zone during spring snowmelt and future hydrologic investigations will benefit from studying the snow and soil

  9. Conifer density within lake catchments predicts fish mercury concentrations in remote subalpine lakes

    Science.gov (United States)

    Eagles-Smith, Collin A.; Herring, Garth; Johnson, Branden L.; Graw, Rick

    2016-01-01

    Remote high-elevation lakes represent unique environments for evaluating the bioaccumulation of atmospherically deposited mercury through freshwater food webs, as well as for evaluating the relative importance of mercury loading versus landscape influences on mercury bioaccumulation. The increase in mercury deposition to these systems over the past century, coupled with their limited exposure to direct anthropogenic disturbance make them useful indicators for estimating how changes in mercury emissions may propagate to changes in Hg bioaccumulation and ecological risk. We evaluated mercury concentrations in resident fish from 28 high-elevation, sub-alpine lakes in the Pacific Northwest region of the United States. Fish total mercury (THg) concentrations ranged from 4 to 438 ng/g wet weight, with a geometric mean concentration (±standard error) of 43 ± 2 ng/g ww. Fish THg concentrations were negatively correlated with relative condition factor, indicating that faster growing fish that are in better condition have lower THg concentrations. Across the 28 study lakes, mean THg concentrations of resident salmonid fishes varied as much as 18-fold among lakes. We used a hierarchal statistical approach to evaluate the relative importance of physiological, limnological, and catchment drivers of fish Hg concentrations. Our top statistical model explained 87% of the variability in fish THg concentrations among lakes with four key landscape and limnological variables: catchment conifer density (basal area of conifers within a lake's catchment), lake surface area, aqueous dissolved sulfate, and dissolved organic carbon. Conifer density within a lake's catchment was the most important variable explaining fish THg concentrations across lakes, with THg concentrations differing by more than 400 percent across the forest density spectrum. These results illustrate the importance of landscape characteristics in controlling mercury bioaccumulation in fish.

  10. Calcium induces long-term legacy effects in a subalpine ecosystem.

    Directory of Open Access Journals (Sweden)

    Urs Schaffner

    Full Text Available Human activities have transformed a significant proportion of the world's land surface, with profound effects on ecosystem processes. Soil applications of macronutrients such as nitrate, phosphorus, potassium or calcium are routinely used in the management of croplands, grasslands and forests to improve plant health or increase productivity. However, while the effects of continuous fertilization and liming on terrestrial ecosystems are well documented, remarkably little is known about the legacy effect of historical fertilization and liming events in terrestrial ecosystems and of the mechanisms involved. Here, we show that more than 70 years after the last application of lime on a subalpine grassland, all major soil and plant calcium pools were still significantly larger in limed than in unlimed plots, and that the resulting shift in the soil calcium/aluminium ratio continues to affect ecosystem services such as primary production. The difference in the calcium content of the vegetation and the topmost 10 cm of the soil in limed vs. unlimed plots amounts to approximately 19.5 g m(-2, equivalent to 16.3% of the amount that was added to the plots some 70 years ago. In contrast, plots that were treated with nitrogen-phosphorus-potassium fertilizer in the 1930s did not differ from unfertilized plots in any of the soil and vegetation characteristics measured. Our findings suggest that the long-term legacy effect of historical liming is due to long-term storage of added calcium in stable soil pools, rather than a general increase in nutrient availability. Our results demonstrate that single applications of calcium in its carbonated form can profoundly and persistently alter ecosystem processes and services in mountain ecosystems.

  11. Net primary productivity of subalpine meadows in Yosemite National Park in relation to climate variability

    Science.gov (United States)

    Moore, Peggy E.; Van Wagtendonk, Jan W.; Yee, Julie L.; McClaran, Mitchel P.; Cole, David N.; McDougald, Neil K.; Brooks, Matthew L.

    2013-01-01

    Subalpine meadows are some of the most ecologically important components of mountain landscapes, and primary productivity is important to the maintenance of meadow functions. Understanding how changes in primary productivity are associated with variability in moisture and temperature will become increasingly important with current and anticipated changes in climate. Our objective was to describe patterns and variability in aboveground live vascular plant biomass in relation to climatic factors. We harvested aboveground biomass at peak growth from four 64-m2 plots each in xeric, mesic, and hydric meadows annually from 1994 to 2000. Data from nearby weather stations provided independent variables of spring snow water content, snow-free date, and thawing degree days for a cumulative index of available energy. We assembled these climatic variables into a set of mixed effects analysis of covariance models to evaluate their relationships with annual aboveground net primary productivity (ANPP), and we used an information theoretic approach to compare the quality of fit among candidate models. ANPP in the xeric meadow was negatively related to snow water content and thawing degree days and in the mesic meadow was negatively related to snow water content. Relationships between ANPP and these 2 covariates in the hydric meadow were not significant. Increasing snow water content may limit ANPP in these meadows if anaerobic conditions delay microbial activity and nutrient availability. Increased thawing degree days may limit ANPP in xeric meadows by prematurely depleting soil moisture. Large within-year variation of ANPP in the hydric meadow limited sensitivity to the climatic variables. These relationships suggest that, under projected warmer and drier conditions, ANPP will increase in mesic meadows but remain unchanged in xeric meadows because declines associated with increased temperatures would offset the increases from decreased snow water content.

  12. Intraguild predation and cannibalism among larvae of detritivorous caddisflies in subalpine wetlands

    Science.gov (United States)

    Wissinger, S.A.; Sparks, G.B.; Rouse, G.L.; Brown, W.S.; Steltzer, Heidi

    1996-01-01

    Comparative data from subalpine wetlands in Colorado indicate that larvae of the limnephilid caddisflies, Asynarchus nigriculus and Limnephilus externus, are reciprocally abundant among habitats - Limnephilus larvae dominate in permanent waters, whereas Asynarchus larvae dominate in temporary basins. The purpose of this paper is to report on field and laboratory experiments that link this pattern of abundance to biotic interactions among larvae. In the first field experiment, growth and survival were compared in single and mixed species treatments in littoral enclosures. Larvae, which eat mainly vascular plant detritus, grew at similar rates among treatments in both temporary and permanent habitats suggesting that exploitative competition is not important under natural food levels and caddisfly densities. However, the survival of Limnephilus larvae was reduced in the presence of Asynarchus larvae. Subsequent behavioral studies in laboratory arenas revealed that Asynarchus larvae are extremely aggressive predators on Limnephilus larvae. In a second field experiment we manipulated the relative sizes of larvae and found that Limnephilus larvae were preyed on only when Asynarchus larvae had the same size advantage observed in natural populations. Our data suggest that the dominance of Asynarchus larvae in temporary habitats is due to asymmetric intraguild predation (IGP) facilitated by a phenological head start in development. These data do not explain the dominance of Limnephilus larvae in permanent basins, which we show elsewhere to be an indirect effect of salamander predation. Behavioral observations also revealed that Asynarchus larvae are cannibalistic. In contrast to the IGP on Limnephilus larvae, Asynarchus cannibalism occurs among same-sized larvae and often involves the mobbing of one victim by several conspecifics. In a third field experiment, we found that Asynarchus cannibalism was not density-dependent and occurred even at low larval densities. We

  13. The Carbon Sequestration Potential of Tree Crop Plantations

    DEFF Research Database (Denmark)

    Kongsager, Rico; Napier, Jonas; Mertz, Ole

    2013-01-01

    Carbon (C) conservation and sequestration in many developing countries needs to be accompanied by socio-economic improvements. Tree crop plantations can be a potential path for coupling climate change mitigation and economic development by providing C sequestration and supplying wood and non......-wood products to meet domestic and international market requirements at the same time. Financial compensation for such plantations could potentially be covered by the Clean Development Mechanism under the United Nations Framework Convention on Climate Change (FCCC) Kyoto Protocol, but its suitability has also...... been suggested for integration into REDD+(reducing emissions from deforestation, forest degradation and enhancement of forest C stocks) currently being negotiated under the United Nations FCCC. We assess the aboveground C sequestration potential of four major plantation crops – cocoa (Theobroma cacao...

  14. The expansion of farm-based plantation forestry in Vietnam.

    Science.gov (United States)

    Sandewall, Mats; Ohlsson, Bo; Sandewall, R Kajsa; Viet, Le Sy

    2010-12-01

    This study targets plantation forestry by farm households (small holders), which is increasing globally and most rapidly in China and Vietnam. By use of an interdisciplinary approach on three study sites in Vietnam, we examined the trends in farmers' tree planting over time, the various pre-requisites for farm-based plantation forestry and its impact on rural people's livelihood strategies, socioeconomic status, income and security. The findings indicated a change from subsistence to cash-based household economy, diversification of farmers' incomes and a transformation of the landscape from mainly natural forests, via deforestation and shifting cultivation, to a landscape dominated by farm-based plantations. The trend of transformation, over a period of some 30 years, towards cash crops and forestry was induced by a combination of policy, market, institutional, infrastructural and other conditions and the existence of professional farming communities, and was most rapid close to the industrial market.

  15. Understory succession in post-agricultural oak plantations

    DEFF Research Database (Denmark)

    Brunet, Jörg; Valtinat, Karin; Mayr, Marian Lajos

    2011-01-01

    -agricultural plantation forests. We studied effects of stand age, forest fragmentation, and soil and canopy conditions on species richness and abundance of four species groups in the understory of post-arable oak plantations in southern Sweden: herbaceous forest specialists, habitat generalists and open land species......, and woody species. The group of forest specialists may approach the richness of continuously forested sites after 60-80 years in non-fragmented plantations, but many forest species were sensitive to habitat fragmentation. Open-land species richness decreased during succession, while the richness of woody......The herbaceous understory forms the richest stratum in temperate broadleaved forests in terms of plant diversity. Understanding the process of understory succession is thus of critical importance for the development of management guidelines for biodiversity restoration in post...

  16. The 2013 FLEX-US Airborne Campaign at the Parker Tract Loblolly Pine Plantation in North Carolina, USA

    Science.gov (United States)

    Middleton, Elizabeth M.; Rascher, Uwe; Corp, Lawrence A.; Huemmrich, K. Fred; Cook, Bruce D.; Noormets, Asko; Schickling, Anke; Pinto, Francisco; Alonso, Luis; Damm, Alexander; hide

    2017-01-01

    The first European Space Agency (ESA) and NASA collaboration in an airborne campaign to support ESA's FLuorescence EXplorer (FLEX) mission was conducted in North Carolina, USA during September-October 2013 (FLEX-US 2013) at the Parker Tract Loblolly Pine (LP) Plantation (Plymouth, NC, USA). This campaign combined two unique airborne instrument packages to obtain simultaneous observations of solar-induced fluorescence (SIF), LiDAR-based canopy structural information, visible through shortwave infrared (VSWIR) reflectance spectra, and surface temperature, to advance vegetation studies of carbon cycle dynamics and ecosystem health. We obtained statistically significant results for fluorescence, canopy temperature, and tower fluxes from data collected at four times of day over two consecutive autumn days across an age class chronosequence. Both the red fluorescence (F685) and far-red fluorescence (F740) radiances had highest values at mid-day, but their fluorescence yields exhibited different diurnal responses across LP age classes. The diurnal trends for F685 varied with forest canopy temperature difference (canopy minus air), having a stronger daily amplitude change for young vs. old canopies. The Photochemical Reflectance Index (PRI) was positively correlated with this temperature variable over the diurnal cycle. Tower measurements from mature loblolly stand showed the red/far-red fluorescence ratio was linearly related to canopy light use efficiency (LUE) over the diurnal cycle, but performed even better for the combined morning/afternoon (without midday) observations. This study demonstrates the importance of diurnal observations for interpretation of fluorescence dynamics, the need for red fluorescence to understand canopy physiological processes, and the benefits of combining fluorescence, reflectance, and structure information to clarify canopy function versus structure characteristics for a coniferous forest.

  17. Earthworm abundance and species composition in abandoned tropical croplands: comparisons of tree plantations and secondary forests.

    Science.gov (United States)

    G. Gonzalez; X. Zou; S. Borges

    1996-01-01

    We compared patterns of earthworms abundance and species composition in tree plantation and secondary forest of Puerto Rico. Tree plantations included pine (Pinus caribea Morelet) and mahogany (Swietenia macrophylla King) established in the 1930's; 1960's; and 1970's; secondary forests were naturally regenerated in areas adjacent to these plantations. We...

  18. Carbon Sequestration in loblolly pine plantations: Methods, limitations, and research needs for estimating storage pools

    Science.gov (United States)

    Kurt Johnsen; Bob Teskey; Lisa Samuelson; John Butnor; David Sampson; Felipe Sanchez; Chris Maier; Steve McKeand

    2004-01-01

    Globally, the species most widely used for plantation forestry is loblolly pine (Pinus taeda L.). Because loblolly pine plantations are so extensive and grow so rapidly, they provide a great potential for sequestering atmospheric carbon (C). Because loblolly pine plantations are relatively simple ecosystems and because such a great volume of...

  19. The effects of energy grass plantations on biodiversity

    Energy Technology Data Exchange (ETDEWEB)

    Semere, T.; Slater, F.

    2005-07-01

    The ecological impact on local wildlife of biomass plantations of three different species of grasses has been monitored in the years 2002 to 2004 inclusive at farms in Herefordshire UK. Two of the grasses were not native to Britain. Wildlife monitored included ground flora, beetles, insects, birds, small mammals, butterflies, bees and hoverflies. The results provide a baseline of biodiversity data from biomass farms in England, although due to poor crop growth, the data from the switch-grass plantation was incomplete. The surveys were carried out by Cardiff University supported financially by the DTI.

  20. Declines in low-elevation subalpine tree populations outpace growth in high-elevation populations with warming

    Science.gov (United States)

    Conlisk, Erin; Castanha, Cristina; Germino, Matthew J.; Veblen, Thomas T; Smith, Jeremy M.; Kueppers, Lara M.

    2017-01-01

    Species distribution shifts in response to climate change require that recruitment increase beyond current range boundaries. For trees with long life spans, the importance of climate-sensitive seedling establishment to the pace of range shifts has not been demonstrated quantitatively.Using spatially explicit, stochastic population models combined with data from long-term forest surveys, we explored whether the climate-sensitivity of recruitment observed in climate manipulation experiments was sufficient to alter populations and elevation ranges of two widely distributed, high-elevation North American conifers.Empirically observed, warming-driven declines in recruitment led to rapid modelled population declines at the low-elevation, ‘warm edge’ of subalpine forest and slow emergence of populations beyond the high-elevation, ‘cool edge’. Because population declines in the forest occurred much faster than population emergence in the alpine, we observed range contraction for both species. For Engelmann spruce, this contraction was permanent over the modelled time horizon, even in the presence of increased moisture. For limber pine, lower sensitivity to warming may facilitate persistence at low elevations – especially in the presence of increased moisture – and rapid establishment above tree line, and, ultimately, expansion into the alpine.Synthesis. Assuming 21st century warming and no additional moisture, population dynamics in high-elevation forests led to transient range contractions for limber pine and potentially permanent range contractions for Engelmann spruce. Thus, limitations to seedling recruitment with warming can constrain the pace of subalpine tree range shifts.

  1. Nitrogen deposition but not ozone affects productivity and community composition of subalpine grassland after 3 yr of treatment.

    Science.gov (United States)

    Bassin, Seraina; Volk, Matthias; Suter, Matthias; Buchmann, Nina; Fuhrer, Jürg

    2007-01-01

    A field experiment was established at 2000 m above sea level (asl) in the central Swiss Alps with the aim of investigating the effects of elevated ozone (O(3)) and nitrogen deposition (N), and of their combination, on above-ground productivity and species composition of subalpine grassland. One hundred and eighty monoliths were extracted from a species-rich Geo-Montani-Nardetum pasture and exposed in a free-air O(3)-fumigation system to one of three concentrations of O(3) (ambient, 1.2 x ambient, 1.6 x ambient) and five concentrations of additional N. Above-ground biomass, proportion of functional groups and normalized difference vegetation index (NDVI) were measured annually. After 3 yr of treatment, the vegetation responded to the N input with an increase in above-ground productivity and altered species composition, but without changes resulting from elevated O(3). N input > 10 kg N ha(-1) yr(-1) was sufficient to affect the composition of functional groups, with sedges benefiting over-proportionally. No interaction of O(3) x N was observed, except for NDVI; positive effects of N addition on canopy greenness were counteracted by accelerated leaf senescence in the highest O(3) treatment. The results suggest that effects of elevated O(3) on the productivity and floristic composition of subalpine grassland may develop slowly, regardless of the sensitive response to increasing N.

  2. Effects of tourism and topography on vegetation diversity in the subalpine meadows of the Dongling Mountains of Beijing, China.

    Science.gov (United States)

    Zhang, Jin-Tun; Xiang, ChunLing; Li, Min

    2012-02-01

    Subalpine meadows in the Dongling Mountains (located at E115º26'-115º40', N40º00'-40º05') of Beijing, China are important for tourism and the provision of ecosystem services. However, because of poor management serious degradation has occurred on these subalpine meadows. The aim of this paper is to present a quantitative analysis of effects of tourism disturbance and topography on the status and diversity of montane meadow communities and to provide direction for improved management. Sixty quadrats of 2 × 2 m(2) along 10 transects were set up to collect data on site characteristics and vegetation status. The relationships between community composition and structure, species diversity, and tourism disturbance and topographic variables were analyzed by multivariate methods (TWINSPAN and CCA). The results showed that eight meadow communities were identified by TWINSPAN. Most of them were seriously degraded. The first CCA axis identified an elevation and tourism disturbance intensity gradient, which illustrated that tourism disturbance and elevation were most important factors influencing meadow types, composition and structure. Some resistant species and response species to tourism disturbance were identified and can be used as indicator species of tourism disturbance. Species richness, heterogeneity and evenness were closely related to tourism disturbance and elevation. It is concluded that tourism disturbance must be controlled to enable grassland rehabilitation to occur in the meadows. Measures of effective management of the meadows were discussed.

  3. Effects of Tourism and Topography on Vegetation Diversity in the Subalpine Meadows of the Dongling Mountains of Beijing, China

    Science.gov (United States)

    Zhang, Jin-Tun; Xiang, Chunling; Li, Min

    2012-02-01

    Subalpine meadows in the Dongling Mountains (located at E115º26'-115º40', N40º00'-40º05') of Beijing, China are important for tourism and the provision of ecosystem services. However, because of poor management serious degradation has occurred on these subalpine meadows. The aim of this paper is to present a quantitative analysis of effects of tourism disturbance and topography on the status and diversity of montane meadow communities and to provide direction for improved management. Sixty quadrats of 2 × 2 m2 along 10 transects were set up to collect data on site characteristics and vegetation status. The relationships between community composition and structure, species diversity, and tourism disturbance and topographic variables were analyzed by multivariate methods (TWINSPAN and CCA). The results showed that eight meadow communities were identified by TWINSPAN. Most of them were seriously degraded. The first CCA axis identified an elevation and tourism disturbance intensity gradient, which illustrated that tourism disturbance and elevation were most important factors influencing meadow types, composition and structure. Some resistant species and response species to tourism disturbance were identified and can be used as indicator species of tourism disturbance. Species richness, heterogeneity and evenness were closely related to tourism disturbance and elevation. It is concluded that tourism disturbance must be controlled to enable grassland rehabilitation to occur in the meadows. Measures of effective management of the meadows were discussed.

  4. Suppression of 4-coumarate-CoA ligase in the coniferous gymnosperm Pinus radiata.

    Science.gov (United States)

    Wagner, Armin; Donaldson, Lloyd; Kim, Hoon; Phillips, Lorelle; Flint, Heather; Steward, Diane; Torr, Kirk; Koch, Gerald; Schmitt, Uwe; Ralph, John

    2009-01-01

    Severe suppression of 4-coumarate-coenzyme A ligase (4CL) in the coniferous gymnosperm Pinus radiata substantially affected plant phenotype and resulted in dwarfed plants with a "bonsai tree-like" appearance. Microscopic analyses of stem sections from 2-year-old plants revealed substantial morphological changes in both wood and bark tissues. This included the formation of weakly lignified tracheids that displayed signs of collapse and the development of circumferential bands of axial parenchyma. Acetyl bromide-soluble lignin assays and proton nuclear magnetic resonance studies revealed lignin reductions of 36% to 50% in the most severely affected transgenic plants. Two-dimensional nuclear magnetic resonance and pyrolysis-gas chromatography-mass spectrometry studies indicated that lignin reductions were mainly due to depletion of guaiacyl but not p-hydroxyphenyl lignin. 4CL silencing also caused modifications in the lignin interunit linkage distribution, including elevated beta-aryl ether (beta-O-4 unit) and spirodienone (beta-1) levels, accompanied by lower phenylcoumaran (beta-5), resinol (beta-beta), and dibenzodioxocin (5-5/beta-O-4) levels. A sharp depletion in the level of saturated (dihydroconiferyl alcohol) end groups was also observed. Severe suppression of 4CL also affected carbohydrate metabolism. Most obvious was an up to approximately 2-fold increase in galactose content in wood from transgenic plants due to increased compression wood formation. The molecular, anatomical, and analytical data verified that the isolated 4CL clone is associated with lignin biosynthesis and illustrated that 4CL silencing leads to complex, often surprising, physiological and morphological changes in P. radiata.

  5. Fix success and accuracy of GPS radio collars in old-growth temperate coniferous forests

    Science.gov (United States)

    Sager-Fradkin, Kimberly A.; Jenkins, Kurt J.; Hoffman, Robert L.; Happe, P.; Beecham, J.; Wright, R.G.

    2007-01-01

    GPS telemetry in coniferous forest ecosystems and that, at present, resource selection patterns of large mammals derived from GPS telemetry should be interpreted cautiously.

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

    Directory of Open Access Journals (Sweden)

    Kerstin Näthe

    2012-09-01

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

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

    Science.gov (United States)

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

    2017-04-01

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

  8. Subalpine vegetation pattern three decades after stand-replacing fire: Effects of landscape context and topography on plant community composition, tree regeneration, and diversity

    Science.gov (United States)

    Jonathan D. Coop; Robert T. Massatti; Anna W. Schoettle

    2010-01-01

    These subalpine wildfires generated considerable, persistent increases in plant species richness at local and landscape scales, and a diversity of plant communities. The findings suggest that fire suppression in such systems must lead to reduced diversity. Concerns about post-fire invasion by exotic plants appear unwarranted in high-elevation wilderness settings.

  9. Verification of satellite radar remote sensing based estimates of boreal and subalpine growing seasons using an ecosystem process model and surface biophysical measurement network information

    Science.gov (United States)

    McDonald, K. C.; Kimball, J. S.; Zimmerman, R.

    2002-01-01

    We employ daily surface Radar backscatter data from the SeaWinds Ku-band Scatterometer onboard Quikscat to estimate landscape freeze-thaw state and associated length of the seasonal non-frozen period as a surrogate for determining the annual growing season across boreal and subalpine regions of North America for 2000 and 2001.

  10. Carex sempervirens tussocks induce spatial heterogeneity in litter decomposition, but not in soil properties, in a subalpine grassland in the Central Alps

    Science.gov (United States)

    Fei-Hai Yu; Martin Schutz; Deborah S. Page-Dumroese; Bertil O. Krusi; Jakob Schneller; Otto Wildi; Anita C. Risch

    2011-01-01

    Tussocks of graminoids can induce spatial heterogeneity in soil properties in dry areas with discontinuous vegetation cover, but little is known about the situation in areas with continuous vegetation and no study has tested whether tussocks can induce spatial heterogeneity in litter decomposition. In a subalpine grassland in the Central Alps where vegetation cover is...

  11. Deforestation induces shallow landsliding in the montane and subalpine belts of the Urbión Mountains, Iberian Range, Northern Spain

    Science.gov (United States)

    García-Ruiz, José M.; Beguería, Santiago; Arnáez, José; Sanjuán, Yasmina; Lana-Renault, Noemí; Gómez-Villar, Amelia; Álvarez-Martínez, Javier; Coba-Pérez, Paz

    2017-11-01

    In this study the spatial distribution of shallow landslides in the upper montane and subalpine belts of the Urbión Mountains (Iberian Range, northern Spain) was investigated, particularly in relation to the spatial organization of deforestation and land cover. The upper montane and subalpine belts have been deforested several times since the Neolithic Period, to enlarge the area of summer grasslands for feeding transhumant sheep flocks. Consequently, the timberline was lowered by 400-600 m, and increased the occurrence of severe erosion processes, particularly shallow landslides. This study shows that most of the landslide scars are in the summer grasslands area, and that a remarkable extent of the subalpine belt area has been subjected to mass movements. In addition to land use, the soil characteristics and topography help explain the development of conditions most favorable to landsliding. Shallow landslide susceptibility was highest in the upper parts of the slopes near the divides, in areas having slope gradients of 10-30° and deep soils with an increasing proportion of clay with depth. The landslides were clustered and not randomly distributed, and the causes of this spatial distribution are discussed. The current trend of woody encroachment in the upper montane and subalpine belts, resulting from decreasing livestock pressure, will probably reduce the susceptibility of these areas to shallow landslides in the future.

  12. Lab and Field Warming Similarly Advance Germination Date and Limit Germination Rate for High and Low Elevation Provenances of Two Widespread Subalpine Conifers

    Directory of Open Access Journals (Sweden)

    Lara M. Kueppers

    2017-11-01

    Full Text Available Accurately predicting upslope shifts in subalpine tree ranges with warming requires understanding how future forest populations will be affected by climate change, as these are the seed sources for new tree line and alpine populations. Early life history stages are particularly sensitive to climate and are also influenced by genetic variation among populations. We tested the climate sensitivity of germination and initial development for two widely distributed subalpine conifers, using controlled-environment growth chambers with one temperature regime from subalpine forest in the Colorado Rocky Mountains and one 5 °C warmer, and two soil moisture levels. We tracked germination rate and timing, rate of seedling development, and seedling morphology for two seed provenances separated by ~300 m elevation. Warming advanced germination timing and initial seedling development by a total of ~2 weeks, advances comparable to mean differences between provenances. Advances were similar for both provenances and species; however, warming reduced the overall germination rate, as did low soil moisture, only for Picea engelmannii. A three-year field warming and watering experiment planted with the same species and provenances yielded responses qualitatively consistent with the lab trials. Together these experiments indicate that in a warmer, drier climate, P. engelmannii germination, and thus regeneration, could decline, which could lead to declining subalpine forest populations, while Pinus flexilis forest populations could remain robust as a seed source for upslope range shifts.

  13. Differentiation of tundra/taiga and boreal coniferous forest wolves: genetics, coat colour and association with migratory caribou.

    Science.gov (United States)

    Musiani, Marco; Leonard, Jennifer A; Cluff, H Dean; Gates, C Cormack; Mariani, Stefano; Paquet, Paul C; Vilà, Carles; Wayne, Robert K

    2007-10-01

    The grey wolf has one of the largest historic distributions of any terrestrial mammal and can disperse over great distances across imposing topographic barriers. As a result, geographical distance and physical obstacles to dispersal may not be consequential factors in the evolutionary divergence of wolf populations. However, recent studies suggest ecological features can constrain gene flow. We tested whether wolf-prey associations in uninterrupted tundra and forested regions of Canada explained differences in migratory behaviour, genetics, and coat colour of wolves. Satellite-telemetry data demonstrated that tundra wolves (n = 19) migrate annually with caribou (n = 19) from denning areas in the tundra to wintering areas south of the treeline. In contrast, nearby boreal coniferous forest wolves are territorial and associated year round with resident prey. Spatially explicit analysis of 14 autosomal microsatellite loci (n = 404 individuals) found two genetic clusters corresponding to tundra vs. boreal coniferous forest wolves. A sex bias in gene flow was inferred based on higher levels of mtDNA divergence (F(ST) = 0.282, 0.028 and 0.033; P wolves from tundra populations exhibited light colouration whereas only 38% of boreal coniferous forest wolves did (chi(2) = 64.52, P < 0.0001). The sharp boundary representing this discontinuity was the southern limit of the caribou migration. These findings show that substantial genetic and phenotypic differentiation in highly mobile mammals can be caused by prey-habitat specialization rather than distance or topographic barriers. The presence of a distinct wolf ecotype in the tundra of North America highlights the need to preserve migratory populations.

  14. Importance of nitrogen cycling hot spots in an alpine-subalpine ecosystem

    Science.gov (United States)

    Darrouzet-Nardi, A.; Bowman, W. D.

    2009-12-01

    Nitrogen (N) availability in soils is influenced by many microbially catalyzed reactions such as N fixation, denitrification, and N mineralization from soil organic matter (SOM). Reaction rates for these processes are heterogeneous across landscapes, often forming hot spots that have disproportionately high N cycling activity. N cycling hot spots have been documented in many ecosystems at hourly to weekly times scales; however, much less is known about the persistence and importance of N cycling hot spots over longer times scales. Furthermore, few studies have investigated multiple landscape-level measurements of different N cycling processes at the same site. Using a mathematical definition of hot spots, a time series of short-term measurements, ion exchange resins deployed for one year, and nitrogen isotopic signatures in SOM, we investigated the importance of hot spots over longer time scales in a 0.89 km2 alpine-subalpine ecosystem at the Niwot Ridge LTER site. Measurements of KCl-extractable inorganic N taken on multiple measurement dates showed that hot moments of N availabilty occurred in some but not all parts of the study site and at varying times throughout the season. Ion exchange resins deployed for one year showed that N availability hot spots were important though not completely dominant over one year (14% of values accounted for 58% of total resin-extractable inorganic N observed). In contrast, isotopic signatures in 219 SOM samples were well approximated by a normal distribution, suggesting that landscape-level N losses through leaching or gas efflux were more constrained. Denitrification was the possible exception: we saw evidence for several likely hot spots in the wetland areas of our study site. The results of this study suggest that short-term hot spots are important for plant ecological dynamics at our study site and for denitrification, but that long-term N cycling hot spots are less important for other parts of the soil N cycle such as N

  15. Fuel deposition rates of montane and subalpine conifers in the central Sierra Nevada, California, USA

    Science.gov (United States)

    van Wagtendonk, J.W.; Moore, P.E.

    2010-01-01

    Fire managers and researchers need information on fuel deposition rates to estimate future changes in fuel bed characteristics, determine when forests transition to another fire behavior fuel model, estimate future changes in fuel bed characteristics, and parameterize and validate ecosystem process models. This information is lacking for many ecosystems including the Sierra Nevada in California, USA. We investigated fuel deposition rates and stand characteristics of seven montane and four subalpine conifers in the Sierra Nevada. We collected foliage, miscellaneous bark and crown fragments, cones, and woody fuel classes from four replicate plots each in four stem diameter size classes for each species, for a total of 176 sampling sites. We used these data to develop predictive equations for each fuel class and diameter size class of each species based on stem and crown characteristics. There were consistent species and diameter class differences in the annual amount of foliage and fragments deposited. Foliage deposition rates ranged from just over 50 g m-2 year-1 in small diameter mountain hemlock stands to ???300 g m-2 year-1 for the three largest diameter classes of giant sequoia. The deposition rate for most woody fuel classes increased from the smallest diameter class stands to the largest diameter class stands. Woody fuel deposition rates varied among species as well. The rates for the smallest woody fuels ranged from 0.8 g m-2 year-1 for small diameter stands of Jeffrey pine to 126.9 g m-2 year-1 for very large diameter stands of mountain hemlock. Crown height and live crown ratio were the best predictors of fuel deposition rates for most fuel classes and species. Both characteristics reflect the amount of crown biomass including foliage and woody fuels. Relationships established in this study allow predictions of fuel loads to be made on a stand basis for each of these species under current and possible future conditions. These predictions can be used to

  16. Soil, plant, and transport influences on methane in a subalpine forest under high ultraviolet irradiance

    Directory of Open Access Journals (Sweden)

    D. Baer

    2009-07-01

    Full Text Available Recent studies have demonstrated direct methane emission from plant foliage under aerobic conditions, particularly under high ultraviolet (UV irradiance. We examined the potential importance of this phenomenon in a high-elevation conifer forest using micrometeorological techniques. Vertical profiles of methane and carbon dioxide in forest air were monitored every 2 h for 6 weeks in summer 2007. Day to day variability in above-canopy CH4 was high, with observed values in the range 1790 to 1910 nmol mol−1. High CH4 was correlated with high carbon monoxide and related to wind direction, consistent with pollutant transport from an urban area by a well-studied mountain-plain wind system. Soils were moderately dry during the study. Vertical gradients of CH4 were small but detectable day and night, both near the ground and within the vegetation canopy. Gradients near the ground were consistent with the forest soil being a net CH4 sink. Using scalar similarity with CO2, the magnitude of the summer soil CH4 sink was estimated at ~1.7 mg CH4 m−2 h−1, which is similar to other temperate forest upland soils. The high-elevation forest was naturally exposed to high UV irradiance under clear sky conditions, with observed peak UVB irradiance >2 W m−2. Gradients and means of CO2 within the canopy under daytime conditions showed net uptake of CO2 due to photosynthetic drawdown as expected. No evidence was found for a significant foliar CH4 source in the vegetation canopy, even under high UV conditions. While the possibility of a weak foliar source cannot be excluded given the observed soil sink, overall this subalpine forest was a net sink for atmospheric methane during the growing season.

  17. Ice duration, winter stratification, and mixing behavior of subalpine lakes in western Maine

    Science.gov (United States)

    Daly, J.; Adams, S.; Abrams, R.; Engel, B.

    2011-12-01

    The timing and duration of both winter and summer periods of stratification periods is not well known for subalpine ponds in the northeastern United States. The remote nature of many of these lakes precludes detailed manual monitoring during the winter and the visual identification of major ice phenological events. These lakes are associated with ecological niches at or near their local elevation maximum that may be at risk due to climate change; historic ice-out records for larger regional lakes indicates a significant trend toward earlier ice-out in response to climate warming. We are using low-cost data loggers to develop high-resolution records characterizing water temperature variability at multiple depths in fifteen lakes 600 - 1000 m elevation. These lakes are located along a 175 km transect in western Maine; most are along the Appalachian Trail. The loggers are recording sub-hourly water temperature and light at the surface, two meters depth, and the bottom of each lake. The timing and duration of winter stratification and ice cover on these lakes are determined by distinctive temperature patterns recorded by the data loggers. The onset of winter stratification is marked by the expected temperature inversion and a slowly increasing hypolimnetic temperature; ice-on follows and is represented by the transition from daily heating cycles to a steady temperature over several days as the ice freezes in around the near-surface logger and energy loss is accomplished through a phase change rather than a drop in temperature. Once the ice is established, temperatures recorded by the near-surface logger vary daily, and are frequently below freezing in response to changing air temperature. Evaluation of winter 2009-2011 records shows that the duration of winter stratification exceeds ice duration at nearly every site. The timing of the onset of stratification is nearly uniform across the study area within each year of data, suggesting a nearly simultaneous response to

  18. Estimating under-canopy ablation in a subalpine red-fir forest, southern Sierra Nevada, California

    Science.gov (United States)

    Kirchner, P. B.; Bales, R. C.; Rice, R.; Musselman, K. N.; Molotch, N. P.

    2010-12-01

    Snow ablation in forested environments is a result of the multi-component energy balance between the snow surface, radiation, topography, and vegetation. While these processes have been successfully described and modeled over small to moderate spatial extents the required data are available from few locations and existing models are computationally intensive. The problem of applying these principals to determining snow coverage for large spatial extents and frequent time steps, required by satellite observations, has not been solved. We present a simplified approach for determining a melt-out date based on modeled incident radiation, percent canopy cover, and leaf area index. This method was tested using results from instrumental data, field observations, and readily available spatial data sets by calibrating the MODIS Snow Covered Area and Grain size/albedo (MODSCAG) model from a snow-dominated site in the Wolverton basin Sequoia National Park; part of the Southern Sierra Nevada Critical Zone Observatory. The percent snow cover determined by MODSCAG from peak accumulation and melt out during the 2008 and 2009 water years were compared to ground observations of both forest gaps and under canopies. Ground based measurements indicated that under-canopy melt out of snow-covered area began earlier and ended 1 to 4 weeks after that indicated by satellite observations, which can only view snow in forest gaps. In our study ablation rates, snow cover duration, leaf area index, canopy closure, and Incoming short and long wave radiation were measured on north and southeast facing plots in a subalpine red fir forest. Results from regression analysis yield an R2=0.99 between modeled and measured short wave radiation and an R2=0.82 between leaf area index and the difference between open and under canopy thermal infrared radiation. Canopy cover and leaf area index were also found to be good predictors of observed melt rates and the melt off date of snow under tree canopies. This

  19. Long-term landscape changes in a subalpine spruce-fir forest in central Utah, USA

    Directory of Open Access Journals (Sweden)

    Jesse L. Morris1

    2015-12-01

    Full Text Available Background: In Western North America, increasing wildfire and outbreaks of native bark beetles have been mediated by warming climate conditions. Bioclimatic models forecast the loss of key high elevation species throughout the region. This study uses retrospective vegetation and fire history data to reconstruct the drivers of past disturbance and environmental change. Understanding the relationship among climate, antecedent disturbances, and the legacy effects of settlement-era logging can help identify the patterns and processes that create landscapes susceptible to bark beetle epidemics. Methods: Our analysis uses data from lake sediment cores, stand inventories, and historical records. Sediment cores were dated with radiometric techniques (14C and 210Pb/137Cs and subsampled for pollen and charcoal to maximize the temporal resolution during the historical period (1800 CE to present and to provide environmental baseline data (last 10,500 years. Pollen data for spruce were calibrated to carbon biomass (C t/ha using standard allometric equations and a transfer function. Charcoal samples were analyzed with statistical models to facilitate peak detection and determine fire recurrence intervals. Results: The Wasatch Plateau has been dominated by Engelmann spruce forests for the last ~10,500 years, with subalpine fir becoming more prominent since 6000 years ago. This landscape has experienced a dynamic fire regime, where burning events are more frequent and of higher magnitude during the last 3000 years. Two important disturbances have impacted Engelmann spruce in the historical period: 1 high-grade logging during the late 19th century; and (2 a high severity spruce beetle outbreak in the late 20th century that killed >90 % of mature spruce (>10 cm dbh. Conclusions: Our study shows that spruce-dominated forests in this region are resilient to a range of climate and disturbance regimes. Several lines of evidence suggest that 19th century logging

  20. Yield models for commercial willow biomass plantations in Sweden

    Energy Technology Data Exchange (ETDEWEB)

    Mola-Yudego, Blas [Faculty of Forestry, University of Joensuu, P.O. Box 111, FI-801 01 Joensuu (Finland); Aronsson, Paer [Department of Crop Production Ecology, Swedish University of Agricultural Sciences (SLU), P.O. Box 7016, S-750 07 Uppsala (Sweden)

    2008-09-15

    A yield model for willow plantations for bioenergy production in Sweden was developed based on recorded production of 2082 commercial plantations during the period 1989-2005. The model predicts yield for the first, second and third harvest using oats (avena) production as agro-climatic index. The mean annual yields were 2.6, 4.2 and 4.5 oven dry tonnes (odt) per hectare during the first, second and third cutting cycles, respectively. The yield correlated inversely with the length of the cutting cycle. The results of the study show significant differences between growers, which suggest the importance of proper management in the establishment and tending of the plantations. Model estimates for 25% of the best growers vary from 4.0 to 6.3 odt ha{sup -1} yr{sup -1} in 5-year-rotation plantations during the first cutting cycle, and from 5.4 to 7.1 odt ha{sup -1} yr{sup -1} in 4-year-rotations for the second cutting cycle. The proposed model can be applied in policy making and for management planning. (author)

  1. Solid-wood production from temperate eucalypt plantations: a ...

    African Journals Online (AJOL)

    This review summarises research on several key areas: silvicultural requirements for solid-wood production; wood properties of plantation-grown eucalypts and the influence of silviculture and genetics on these properties; factors influencing stem defect and decay; balancing silvicultural requirements with maintenance of ...

  2. Financial performance of loblolly and longleaf pine plantations

    Science.gov (United States)

    Steven D. Mills; Charles T. Stiff

    2013-01-01

    The financial performance of selected management regimes for loblolly (Pinus taeda L.) and longleaf pine (P. palustris Mill.) plantations were compared for four cases, each with low- and high-site productivity levels and each evaluated using 5 and 7 percent real discount rates. In all cases, longleaf pine was considered both with...

  3. Copper Deficiency in Pine Plantations in the Georgia Coastal Plain

    Science.gov (United States)

    David B. South; William A. Carey; Donald A. Johnson

    2004-01-01

    Copper deficiencies have been observed on several intensively managed pine plantations in the Georgia Coastal Plain. Loblolly pine (Pinus taeda L.) and slash pine (Pinus elliottii var. elliottii Engelm.) displayed plagiotropic growth within a year after planting on very acid, sandy soils. Typically, symptoms show...

  4. 1 Soil Organic Carbon Dynamics under different plantation crops of ...

    African Journals Online (AJOL)

    to the relatively slow rate of cocoa leaf litter materials decomposition (Owusu-. Sekyere, et al, 2006; Triadiati, et al., 2011), cocoa leaf form about 80 % of the heavy mat of leaf falls, with subsequent low rate of addition of organic carbon to the soil reserve. The lower SOC (1.34g/kg) for the old coffee plantation may probably ...

  5. Ecophysiology of Acacia species in wet–dry tropical plantations ...

    African Journals Online (AJOL)

    We explored leaf-level photosynthetic activity and leaf water potential (Ψleaf) of three field-grown Acacia tree species (aged between 7 and 18 months) in contrasting wet–dry tropical plantations in southern Vietnam and northern Australia. Light-saturated photosynthetic rate (A1500) declined throughout the morning and ...

  6. Soil carbon and nutrient accumulation under forest plantations in ...

    African Journals Online (AJOL)

    Tree and soil interactions may result in changes in soil carbon and nutrient contents. Forest plantations made up of monodominant stands of 17 different species, some native and some exotic to Rwanda, as well as a stand with mixed native tree species were investigated. Biosequential sampling was used followed by basic ...

  7. Effects of plantation residue management on the community ...

    African Journals Online (AJOL)

    There is a limited availability of land for the expansion of South African black wattle plantations. One way to increase productivity is to ensure the survival of seedlings during regeneration, thereby increasing the stocking of compartments. Soil invertebrate pests constitute one of the important causes of seedling mortality.

  8. Nutrient cycling in primary, secondary forests and cocoa plantation ...

    African Journals Online (AJOL)

    Less leaf litter production and high rainfall regimes in South America and southeast Asia probably contributed to the lower annual nutrient fluxes recorded than that of the dry semi-deciduous tropical forest in Ghana. The soil under cocoa plantation was higher in Ca than in the secondary and primary forests soils.

  9. Can the Mangombe forest plantation contribute to restore and ...

    African Journals Online (AJOL)

    This research, conducted in the tropical rainforest, is focused on restoration of tree diversity through natural regeneration mechanism in the 49 year-old Mangombe forest plantation. 12 plots were surveyed, 6 with large transects and the 6 others under regrowth. In each plot, two subplots with 400 m² each were demarcated ...

  10. Research strategies for increasing productivity of intensively managed forest plantations

    Science.gov (United States)

    E.D. Vance; D.A. Maguire; R.S. Zalesny

    2010-01-01

    Intensive management practices increase productivity of forest plantations by reducing site, stand, and biological limitations to dry matter production and by maximizing the allocation of production to harvestable tree components. The resulting increase allows greater fiber production from a smaller land base and provides market incentives to keep these lands under...

  11. Site Management and Productivity in Tropical Forest Plantations

    Science.gov (United States)

    A. Tiarks; E.K.S. Nambiar; C. Cossalter

    1998-01-01

    Tropical countries are expanding plantation forestry to develop sustainable woodproduction systems. Much of this is based on short rotations of exotic species. These systems require large capital investments, represent intensive land use and increase the demands on the soil. To develop options for maintaining or increasing productivity a partner-project was initiated...

  12. Soil nematode population studies of some selected plantation crops ...

    African Journals Online (AJOL)

    The study was conducted on citrus, plantain and pineapple plantations on the Teaching and Research Farm of the School of Agriculture, University of Cape Coast. The survey also covered undisturbed coastal thicket near the site of the study. The aim of the survey was to identify types and population levels of plant parasitic ...

  13. Simulation of hydrology of short rotation hardwood plantations

    Science.gov (United States)

    John E. Parsons; Carl C. Trettin

    2001-01-01

    A 76 ha hardwood plantation at Trice Research Forest near Sumter, SC is being usedto study forest hydrology on an operational scale. The overall objective of this project is to develop tools to enable forest managers to assess and manage sustainable short rotation woody crop production systems. This paper reports on the use of the water management model, WATRCOM, as a...

  14. Quambalaria species: increasing threat to eucalypt plantations in ...

    African Journals Online (AJOL)

    Spotted gum Corymbia citriodora subsp . variegata and C. maculata) is a valuable source of commercial timber and suitable for a wide range of different soil types in eastern Australia. The main biological constraint to further expansion of spottedgum plantations is Quambalaria shoot blight caused by the fungus ...

  15. Biomass harvesting in Eucalyptus plantations in Western Australia ...

    African Journals Online (AJOL)

    Australia is at an early stage of exploring the use of forest biomass to generate energy. This study evaluated the biomass yield and the productivity rates of equipment for harvesting biomass in a poor-quality eucalypt plantation. The operation consisted of a tracked feller-buncher, grapple skidder and mobile chipper.

  16. Effect of nitrogen and phosphorous on Farm Plantations in various ...

    African Journals Online (AJOL)

    use

    Ecological effects include the environmental condition at which living organism can easily survive. In case of agroforestry, a type of soil is one of the major factors for the classification of different suitable species of plants. (Khan and Chaudhry, 2007). A comparison of the characteristics of soils under various farm plantations.

  17. Colour Variation In Teak ( Tectona grandis ) Wood From Plantations ...

    African Journals Online (AJOL)

    Teak trees totaling 46 were felled from 8 different plantation stands in four different ecological zones of Ghana (moist semi-deciduous forest, MSDF; dry semi-deciduous forest, DSDF; transition savanna forest; and savanna forest). Colour measurements were made on strips obtained from logs cut from the felled trees.

  18. Effect of nitrogen and phosphorous on Farm Plantations in various ...

    African Journals Online (AJOL)

    Effect of nitrogen and phosphorous on Farm Plantations in various agroecological zones of Punjab, Pakistan. SMA Rahim, S Hasnain, J Farkhanda. Abstract. Against a world average of 25% area under forests, Pakistan has around 5% and Punjab has only 2% area under manageable and productive forests. The present ...

  19. pesticide residues in water from tpc sugarcane plantations and ...

    African Journals Online (AJOL)

    ABSTRACT. We report herein, the analysis of water samples collected from TPC Sugarcane Plantation and its environs in Kilimanjaro region, which is the earliest intensive user of pesticides in Tanzania. A total of 50 water samples collected from 18 sampling sites between 2000 and 2001 were analyzed for pesticide ...

  20. Health and nutrition of plantation eucalypts in Asia | Dell | Southern ...

    African Journals Online (AJOL)

    Understanding site fertility constraints has lifted productivity of eucalypt plantations in East and South-east Asia through targeted application of inorganic fertilisers. Whilst most attention has been given to the supply of nitrogen and phosphorus in silvicultural prescriptions, and inoculation with mycorrhizal fungi is being ...

  1. Eucalypt pests and diseases: growing threats to plantation productivity

    African Journals Online (AJOL)

    There are also growing examples of host-specific pathogens native to areas where eucalypts have been planted as non-natives, which have undergone sometimes surprising host jumps. These 'new pathogens\\' threaten not only plantation forestry based on non-natives, but also eucalypts and their relatives in areas where ...

  2. Effects of Tectona grandis (teak) plantation on soil microorganisms ...

    African Journals Online (AJOL)

    Effects of Tectona grandis age series plantation on soil microorganisms were investigated. Using completely randomised block design (CRBD) soil samples were collected from the rhizosphere, non-rhizosphere and the natural forest for December, 2003, February, 2004, April, 2004, and June, 2004. The collected samples ...

  3. Nutritional sustainability of Eucalyptus plantations : a case study at ...

    African Journals Online (AJOL)

    The nutritional sustainability of a short-rotation Eucalyptus grandis plantation system was evaluated in a trial located at Karkloof, KwaZulu-Natal, South Africa, by determining nutrient pools and fluxes. Nutrient pools in the forest floor and biomass (above- and below-ground) were assessed by destructive sampling. The size ...

  4. Impact of Eucalyptus plantations on the avian breeding community ...

    African Journals Online (AJOL)

    The nesting bird species in natural forests and Eucalyptus plantations on the Amani Plateau, East Usambara, were studied during the breeding season of September 2003 to March 2004. Some forest birds — like barbets, batis, broadbills, doves, flycatchers, greenbuls, hornbills, and tinkerbirds — utilised similar nest sites ...

  5. Bird use of banana plantations adjacent to Kibale National Park ...

    African Journals Online (AJOL)

    Bird use of banana plantations adjacent to Kibale National Park, Uganda: evaluating the conservation value of a matrix habitat. ... may provide suitable habitat for some nectarivores, but are of limited value for small birds that eat invertebrates and fruit. Keywords: agriculture, biodiversity, bird community, forest fragmentation ...

  6. Cottonwood Response to Nitrogen Related To Plantation Age and Site

    Science.gov (United States)

    B.G. Blackmon

    1977-01-01

    When applied at plantation age 4,336 kg N/ha increased diameter growth of cottonwood on Sharkey clay by 33 percent over unfertilized controls. Fertilizing at ages 2 and 3 resulted in no response, nor was there any benefit from applying nitrogen fertilizer to cottonwood on Commerce silt loam. On both sites, foliar N levels were increased by fertilization regardless of...

  7. Agroecological practices in oil palm plantations: examples from the field

    Directory of Open Access Journals (Sweden)

    Bessou Cécile

    2017-05-01

    Full Text Available Palm oil is nowadays the first vegetable oil consumed worldwide. Given the world population growth and the increasing demand in fat for food and fuel, the increase in oil palm production is expected to continue. It is thus important to find ways of reducing the ecological impact of oil palm plantations at both the agroecosystem and the mill supply area levels, by improving agricultural practices and land uses. This is where agroecology can play a very critical role. The present article gathers short stories on agroecological practices currently taking place in oil palm plantations in South-East Asia. Such stories notably highlight the importance of the various palm co-products and how appropriate recycling strategies can allow for reducing external inputs to both the field and the mill. Besides limiting environmental impacts thanks to such savings, several co-products used as organic amendments can even help to maintain or enhance soil quality. Other stories explored agroecological practices developed for biological controls. Although integrated pest management has been applied in palm plantations for a long time, the underlying mechanisms are still not fully deciphered and practices still need to be improved. More knowledge is needed in order to better account for the holistic role of biodiversity and arbitrate trade-offs between practices and ecosystem services, at both plantation and landscape levels.

  8. Biomass yield and biomass functions for plantation grown Nauclea ...

    African Journals Online (AJOL)

    This paper presents biomass yield and functions for estimating total above ground biomass (TAGB), stem, branch and foliage biomass for even-aged plantations of Nauclea diderrichii (Opepe) in Nigeria. Data were obtained from 81 trees, harvested from stands of different ages. TAGB of Opepe ranged from 32.5 t ha-1 (5 ...

  9. Evaluation of Carbon sequestration in pure and mixed plantations of ...

    African Journals Online (AJOL)

    The present study was conducted to investigate the effect of tree mixture on Carbon sequestration in cupressus arizonica plantations. Emission of carbon dioxide via human activities is known as the main cause of global warming. Therefore, in this study, soil carbon sequestration in mixed and pure stands was measured in ...

  10. Evaluation of maize growth in Bombax buonopozense plantation ...

    African Journals Online (AJOL)

    This experiment was conducted on the Bombax buonopozense plantation at the arboretum of the Forestry Institute of Nigeria during the wet planting season of year 2014. There were three treatments viz: maize planted within rows of trees under non pruned bombax trees, pruned bombax trees and the control which was an ...

  11. Water balance of drained plantation watersheds in North Carolina

    Science.gov (United States)

    Johnny M. Grace; R. W. Skaggs

    2006-01-01

    A 3-year study to evaluate the effect of thinning on the hydrology of a drained loblolly pine (Pinus taeda L.) plantation was conducted in eastern North Carolina. The study utilized a paired watershed design with a 40-ha thinned watershed (WS5) and a 16-ha control watershed (WS2). Data from the field experiment conducted from 1999-2002 was used to...

  12. Germination frequency of woody species in exotic plantation and ...

    African Journals Online (AJOL)

    ... 21-year old exotic plantations and a bush fallow land use system at Forestry Institute of Nigeria (FRIN) Umuahia, Abia State, the germination of indigenous woody species and litterfall were monitored. Enumeration of indigenous woody species was carried out within a 3.5 x 3.5 quadrat plot. The Pine/Gmelina mixed stand ...

  13. Catenary Variation of Soil Properties under Oil Palm Plantation in ...

    African Journals Online (AJOL)

    Catenary Variation of Soil Properties under Oil Palm Plantation in South Western Nigeria. ... There were no significant variations in the levels of extractable manganese, copper and zinc between the upper, middle and lower slopes but extractable iron was significantly higher in the lower slope due to the occurrence of more ...

  14. Herbaceous weed control in loblolly pine plantations using flazasulfuron

    Science.gov (United States)

    Andrew W. Ezell; Jimmie L. Yeiser

    2015-01-01

    A total of 13 treatments were applied at four sites (two in Mississippi and two in Texas) to evaluate the efficacy of flazasulfuron applied alone or in mixtures for providing control of herbaceous weeds. All sites were newly established loblolly pine (Pinus taeda L.) plantations. Plots were evaluated monthly until 180 days after treatment. No phytotoxicity on pine...

  15. Evaluation of seasonal variations of remotely sensed leaf area index over five evergreen coniferous forests

    Science.gov (United States)

    Wang, Rong; Chen, Jing M.; Liu, Zhili; Arain, Altaf

    2017-08-01

    Seasonal variations of leaf area index (LAI) have crucial controls on the interactions between the land surface and the atmosphere. Over the past decades, a number of remote sensing (RS) LAI products have been developed at both global and regional scales for various applications. These products are so far only validated using ground LAI data acquired mostly in the middle of the growing season. The accuracy of the seasonal LAI variation in these products remains unknown and there are few ground data available for this purpose. We performed regular LAI measurements over a whole year at five coniferous sites using two methods: (1) an optical method with LAI-2000 and TRAC; (2) a direct method through needle elongation monitoring and litterfall collection. We compared seasonal trajectory of LAI from remote sensing (RS LAI) with that from a direct method (direct LAI). RS LAI agrees very well with direct LAI from the onset of needle growth to the seasonal peak (R2 = 0.94, RMSE = 0.44), whereas RS LAI declines earlier and faster than direct LAI from the seasonal peak to the completion of needle fall. To investigate the possible reasons for the discrepancy, the MERIS Terrestrial Chlorophyll Index (MTCI) was compared with RS LAI. Meanwhile, phenological metrics, i.e. the start of growing season (SOS) and the end of growing season (EOS), were extracted from direct LAI, RS LAI and MTCI time series. SOS from RS LAI is later than that from direct LAI by 9.3 ± 4.0 days but earlier than that from MTCI by 2.6 ± 1.9 days. On the contrary, for EOS, RS LAI is later than MTCI by 3.3 ± 8.4 days and much earlier than direct LAI by 30.8 ± 7.2 days. Our results suggest that the seasonal trajectory of RS LAI well captures canopy structural information from the onset of needle growth to the seasonal peak, but is greatly influenced by the decrease in leaf chlorophyll content, as indicated by MTCI, from the seasonal peak to the completion of needle fall. These findings have significant

  16. Evaluation of the load carrying capacity of large cross section coniferous timber in standing structures

    Directory of Open Access Journals (Sweden)

    Arriaga, F.

    2005-12-01

    Full Text Available A total of 85 large section timber pieces (Pinus sylvestris L. and Pinus pinaster Alt. found in a number of old buildings were visually analyzed and graded pursuant to Spanish standard UNE 56544 and German standard 4074. The object was to formulate a non-destructive method to reliably and effectively determine the mechanical properties of existing timber structures with large cross sections. A new system is proposed based on the chief visual grading parameters and consisting in a single grade; the percentage of rejections with this system is low. In this regard, a specific strength class is established for large cross section members in existing coniferous wood structures, namely F14/E9/D380 (MOR of 14 N/mm2, MOE of 9 kN/mm2 and characteristic density of 380 kg/m3. The use of ultrasonic velocity is proposed to define the next higher strength class - F16/E10/D380, to which timber with velocities of 4,900 m/s or over would be assigned.

    Se han clasificado visualmente 85 piezas de madera de gruesa sección (Pino silvestre y Pino pinaster procedentes de varios edificios antiguos de acuerdo con las normas UNE 56544 y DIN 4074. El objetivo es establecer una metodología no destructiva para asignar propiedades mecánicas a las piezas de estructuras existentes de madera con gruesas escuadrías con un nivel de seguridad y de rendimiento aceptables. Se propone un único grado de calidad con un porcentaje bajo de rechazos, aplicando los principales parámetros de la clasificación visual. De esta forma, se establece una clase resistente específica para las piezas de gruesa escuadría de estructuras de madera de conifera existentes definida como FI4/E9/D380 (resistencia característica a flexión igual a 14 N/mm2, módulo de elasticidad de 9 kN/mn2 y densidad característica de 380 kg/m3. Para alcanzar una clase resistente superior se propone utilizar el parámetro añadido de la

  17. Radionuclide behaviour and transport in a coniferous woodland ecosystem. Vegetation, invertebrates and wood mice, Apodemus sylvaticus

    Energy Technology Data Exchange (ETDEWEB)

    Copplestone, D.; Johnson, M.S.; Toal, M.E. [Industrial Ecology Research Centre, School of Biological Sciences, University of Liverpool, Liverpool (United Kingdom); Jones, S.R.; Jackson, D. [Westlakes Scientific Consulting, Princess Royal Building, Westlakes Science and Technology Park, Moor Row, Cumbria (United Kingdom)

    1999-10-01

    Activity concentrations of radionuclides (134Cs, 137Cs, 238Pu, 239+240Pu and 241Am) were measured in vegetation, invertebrates and wood mice, Apodemus sylvaticus, collected in Lady Wood, a coniferous woodland in the vicinity of the British Nuclear Fuels reprocessing plant at Sellafield, Cumbria, UK. Vegetation was of low diversity and biomass with activity concentrations ranging from 1 to 5 Bq kg{sup -1} (134Cs), 0.3-0.5 Bq kg{sup -1} (238Pu), 0.8-8 Bq kg{sup -1} (239+240Pu), and 0.6-16 Bq kg{sup -1} (241Am), dry wt. Caesium-137 activity concentrations were high compared to the reference site in Cheshire, varying between 65 and 280 Bq kg{sup -1}. Marked inter-specific and temporal differences in radionuclide activity concentrations were recorded for invertebrate populations. Caesium-137, 238Pu, 239+240Pu and 241Am activity concentrations in detritivorous invertebrates were consistently higher than in all other invertebrate groups reflecting contamination of the leaf litter. The activity concentrations in detritivores increased during the autumn and winter, reflecting changes in diet as food sources varied throughout the year. Activity concentrations in invertebrates caught in Lady Wood were generally an order of magnitude higher than for the reference site. Activity concentrations in wood mice varied between 7 and 150 Bq kg{sup -1} (137Cs), 0.1-0.3 Bq kg{sup -1} (238Pu), 0.1-0.6 Bq kg{sup -1} (239+240Pu) and 0.2-0.4 Bq kg{sup -1} (241Am). There were clear differences in the activity concentration of 137Cs (P<0.01), 239+240Pu (P<0.05) and 241Am (P<0.05) in animals caught in Lady Wood compared to the reference site. However, the activity concentrations for 238Pu were similar at both sites, reflecting a low gastrointestinal transfer. Seasonal variation in activity concentrations was observed for 137Cs, 238Pu and 241Am. This variation is attributed to changes in the age structure of the population and diet throughout the year.

  18. Plant species, not climate, controls aboveground biomass O2:CO2 exchange ratios in deciduous and coniferous ecosystems

    Science.gov (United States)

    Gallagher, Morgan E.; Liljestrand, Frasier L.; Hockaday, William C.; Masiello, Caroline A.

    2017-09-01

    The oxidative ratio (OR) is the O2:CO2 ratio associated with photosynthesis, respiration, and other ecosystem gas exchange processes and can be reported on the scale of an individual leaf, an ecosystem, up to the entire terrestrial biosphere. The OR of the terrestrial biosphere is used to partition anthropogenic CO2 between oceanic and terrestrial carbon sinks, and the ease of measurement of this property on smaller scales suggests its potential for other uses. However, controls on the natural variation of OR are not understood in either organic matter pools or fluxes, and this lack of basic information limits the use of the tracer. Here we assess the annual variability of the OR of photosynthesis over decade for two temperate forests, one coniferous and one deciduous, and show that the photosynthetic OR signature is strongly dominated by plant species. We determined the OR of this flux by measuring the OR of carbon pools that close on annual or shorter timescales (leaves and individual tree rings), via solid-state 13C NMR spectroscopy and elemental analysis. Leaf litter OR is different between coniferous and deciduous forests, but tree bole OR is constant between species. There was no significant change in leaf litter OR with time, nor any correlations between leaf litter OR and temperature or precipitation. During this time growing season precipitation varied by 95% from the time period average, and growing season temperature by 22%, demonstrating that on the decadal scale photosynthetic OR is invariant over significant shifts in these climate parameters.

  19. Modelling canopy radiation budget through multiple scattering approximation: a case study of coniferous forest in Mexico City Valley

    Science.gov (United States)

    Silván-Cárdenas, Jose L.; Corona-Romero, Nirani

    2015-10-01

    In this paper, we describe some results from a study on hyperspectral analysis of coniferous canopy scattering for the purpose of estimating forest biophysical and structural parameters. Georeferenced airborne hyperspectral measurements were taken from a flying helicopter over a coniferous forest dominated by Pinus hartweguii and Abies religiosa within the Federal District Conservation Land in Mexico City. Hyperspectral data was recorded in the optical range from 350 to 2500 nm at 1nm spectral resolution using the FieldSpec 4 (ASD Inc.). Spectral measurements were also carried out in the ground for vegetation and understory components, including leaf, bark, soil and grass. Measurements were then analyzed through a previously developed multiple scattering approximation (MSA) model, which represents above-canopy spectral reflectance through a non-linear combination of pure spectral components (endmembers), as well as through a set of photon recollision probabilities and interceptance fractions. In this paper we provide an expression for the canopy absorptance as the basis for estimating the components of canopy radiation budget using the MSA model. Furthermore, since MSA does not prescribe a priori the endmembers to incorporate in the model, a multiple endmember selection method (MESMSA) was developed and tested. Photon recollision probabilities and interceptance fractions were estimated by fitting the model to airborne spectral reflectance and selected endmembers where then used to estimate the canopy radiation budget at each measured location.

  20. [Soil aggregate stability and soil organic carbon characteristics in Quercus variabilis and Pinus tabulaeformis plantations in Beijing area].

    Science.gov (United States)

    Liu, Yan; Zha, Tong-Gang; Wang, Yi-Kun; Wang, Gao-min

    2013-03-01

    Based on the field survey and laboratory analysis, this paper studied the soil aggregate stability and soil organic carbon characteristics in Quercus variabilis and Pinus tabulaeformis plantations in Beijing area. In the two plantations, the contents of soil macro-aggregates decreased with soil depth. In P. tabulaeformis plantation, soil macro-aggregates (>0.25 mm) occupied the majority, accounting for 71% -77% of the total; whereas in Q. variabilis plantation, no significant difference was observed in the contents of soil macro-aggregates and micro-aggregates (soil aggregates in P. tabulaeformis plantation were significantly higher than those in Q. variabilis plantation, and the fractal dimension (D) of the soil water-stable aggregates in P. tabulaeformis plantation was lower than that in Q. variabilis plantation, suggesting that P. tabulaeformis plantation was more favorable for the soil aggregate stability than Q. variabilis plantation. Also in the two plantations, the organic carbon content in soil water-stable aggregates decreased with soil depth. The organic carbon content in soil macro-aggregates was significantly higher in P. tabulaeformis plantation (58% -83%) than in Q. variabilis plantation (49% -66% ). It was suggested that in Beijing area, P. tabulaeformis plantation was more beneficial to the soil organic carbon protection, as compared with Q. variabilis plantation.

  1. Ecologia dello Scoiattolo comune (Sciurus vulgaris in boschi alpini di conifere: relazioni spaziali e trofiche

    Directory of Open Access Journals (Sweden)

    Sandro Bertolino

    2003-10-01

    Full Text Available Lo scoiattolo comune è una specie generalista, legata per l?alimentazione principalmente alla disponibilità di semi di latifoglie o conifere. Numerosi fattori che influiscono sulla condizione individuale e sulla dinamica di popolazione (massa corporea, sopravvivenza invernale, successo riproduttivo sono correlati con la produttività dei boschi. Queste relazioni non sono mai state verificate per le foreste alpine di conifere, habitat dove lo scoiattolo comune sembra ben adattato. Per tale motivo è stato avviato uno studio sulla specie nel Parco Nazionale del Gran Paradiso. La ricerca è stata condotta in due aree: una in foresta mista di conifere (Cogne, 50 ha, Picea abies 45%, Larix decidua 54%, alberi morti 1%, l?altra in pecceta (Rhemes, 69 ha, Picea abies 85%, Larix decidua 11%, alberi morti 4%. La produzione energetica dei boschi (semi delle conifere è stata valutata moltiplicando il n. di piante/ha x il n. coni/pianta (contati su 60 alberi campione x il n. semi/cono x il peso medio dei semi, trasformando poi la biomassa in Mj. Le catture sono state effettuate tre volte l?anno, da agosto 2000 a ottobre 2002 con trenta trappole modello Tomahawk 201. Dopo la cattura e il rilascio degli animali, la trappola era ispezionata e le feci raccolte e conservate in etanolo 70% per la ricerca di spore fungine. Diciotto scoiattoli nel 2001 e 13 nel 2002 sono stati dotati di radiocollare (PD- 2C Holohil Systems Ltd. e seguiti in estate e autunno. La densità autunnale post-riproduttiva è stata di 0,30-0,35 animali/ha-1 a Rhemes e 0,27-0,45 animali/ha-1 a Cogne. La densità autunnale dei maschi è risultata correlata con la produzione di semi dell?anno precedente (r = 0,96, g.l. = 4, P = 0,003, mentre per le femmine è emersa una correlazione positiva confrontando le densità estive delle femmine nel 2000 con la produzione di semi di conifere nel 1999 e le densità del 2001 e del 2002 con la

  2. Similarity of nutrient uptake and root dimensions of Engelmann spruce and subalpine fir at two contrasting sites in Colorado

    Energy Technology Data Exchange (ETDEWEB)

    Yanai, R; McFarlane, K; Lucash, M; Kulpa, S; Wood, D

    2009-10-09

    Nutrient uptake capacity is an important parameter in modeling nutrient uptake by plants. Researchers commonly assume that uptake capacity measured for a species can be used across sites. We tested this assumption by measuring the nutrient uptake capacity of intact roots of Engelmann spruce (Picea engelmanni Parry) and subalpine fir (Abies lasiocarpa (Hook.) Nutt.) at Loch Vale Watershed and Fraser Experimental Forest in the Rocky Mountains of central Colorado. Roots still attached to the tree were exposed to one of three concentrations of nutrient solutions for time periods ranging from 1 to 96 hours, and solutions were analyzed for ammonium, nitrate, calcium, magnesium, and potassium. Surprisingly, the two species were indistinguishable in nutrient uptake within site for all nutrients (P > 0.25), but uptake rates differed by site. In general, nutrient uptake was higher at Fraser (P = 0.01, 0.15, 0.03, 0.18 for NH{sub 4}{sup +}, NO{sub 3}{sup -}, Ca{sup 2+}, and K{sup +}, respectively), which is west of the Continental Divide and has lower atmospheric deposition of N than Loch Vale. Mean uptake rates by site for ambient solution concentrations were 0.12 {micro}mol NH{sub 4}{sup +} g{sub fwt}{sup -1} h{sup -1}, 0.02 {micro}mol NO{sub 3}{sup -} g{sub fwt}{sup -1}, 0.21 {micro}mol Ca{sup 2+} g{sub fwt}{sup -1} h{sup -1}, and 0.01 {micro}mol Mg{sup 2+} g{sub fwt}{sup -1} h{sup -1} at Loch Vale, and 0.21 {micro}mol NH{sub 4}{sup +} f{sub fwt}{sup -1}h{sup -1}, 0.04 {micro}mol NO{sub 3}{sup -} g{sub fwt}{sup -1} h{sup -1}, 0.51 {micro}mol Ca{sup 2+}g{sub fwt}{sup -1}h{sup -1}, and 0.07 {micro}mol Mg{sup 2+} f{sub fwt}{sup -1}h{sup -1} at Fraser. The importance of site conditions in determining uptake capacity should not be overlooked when parameterizing nutrient uptake models. We also characterized the root morphology of these two species and compared them to other tree species we have measured at various sites in the northeastern USA. Engelman spruce and subalpine fir

  3. A New Ecological Model Oriented Forest Plantation Map of China

    Science.gov (United States)

    Ying, Q.; Hurtt, G. C.; Zhao, M.; Chini, L. P.; Fisk, J. P.; Liang, S.

    2012-12-01

    China has been implementing unprecedented afforestation programs since the middle 1980s to restore ecosystem services and mitigate climate change by sequestering carbon from atmosphere to biosphere. Over the past three decades, China has planted 120-160 million hectares of trees, accounting for about 70% of its current forested area. Planted forest ecosystems are different in biophysical and biochemical characteristics from natural forests. To accurately estimate regional carbon storage change in China, the spatio-temporal information of planted forests must be taken into account and distinguished from natural forests. The goal of this research is to create the first ecological model-oriented plantation map of China using coupled remote sensing data and statistical data. We divided our research into three steps. Firstly, to quantitatively characterize forest-plantation area, we proposed a Plantation Potential Index (PPI) that demonstrated the possibility of artificial forest establishment in a 1km by 1km grid. MODIS Vegetation Continuous Fields (VCF) data produced by the Global Land Cover Facility (GLCF) were employed to distinguish forest and non-forest area for each year from 2001-2010. Then time series of Normalized Differences Vegetation Index (NDVI) from MODIS were utilized to identify new growth forests and their establishment time by using a logistic growth function. With the identified new forests, Digital Elevation Model (DEM), NDVI variance, soil degradation level and the ratio of annual Land Surface Temperature maximum (LSTmax) to Enhanced Vegetation Index maximum (EVImax) were combined to construct PPI for each grid. Secondly, we built up a spatial allocation model to automatically assign statistical data from each province to map pixels based on their PPI values. Finally, we validated our plantation map at locations where independent field or documentary data were available and depicted plantation classification accuracy. After careful examination, we

  4. [Effects of snow pack on soil nitrogen transformation enzyme activities in a subalpine Abies faxioniana forest of western Sichuan, China].

    Science.gov (United States)

    Xiong, Li; Xu, Zhen-Feng; Wu, Fu-Zhong; Yang, Wan-Qin; Yin, Rui; Li, Zhi-Ping; Gou, Xiao-Lin; Tang, Shi-Shan

    2014-05-01

    This study characterized the dynamics of the activities of urease, nitrate reductase and nitrite reductase in both soil organic layer and mineral soil layer under three depths of snow pack (deep snowpack, moderate snowpack and shallow snowpack) over the three critical periods (snow formed period, snow stable period, and snow melt period) in the subalpine Abies faxoniana forest of western Sichuan in the winter of 2012 and 2013. Throughout the winter, soil temperature under deep snowpack increased by 46.2% and 26.2%, respectively in comparison with moderate snowpack and shallow snowpack. In general, the three nitrogen-related soil enzyme activities under shallow snowpack were 0.8 to 3.9 times of those under deep snowpack during the winter. In the beginning and thawing periods of seasonal snow pack, shallow snowpack significantly increased the activities of urease, nitrate and nitrite reductase enzyme in both soil organic layer and mineral soil layer. Although the activities of the studied enzymes in soil organic layer and mineral soil layer were observed to be higher than those under deep- and moderate snowpacks in deep winter, no significant difference was found under the three snow packs. Meanwhile, the effects of snowpack on the activities of the measured enzymes were related with season, soil layer and enzyme type. Significant variations of the activities of nitrogen-related enzymes were found in three critical periods over the winter, and the three measured soil enzymes were significantly higher in organic layer than in mineral layer. In addition, the activities of the three measured soil enzymes were closely related with temperature and moisture in soils. In conclusion, the decrease of snow pack induced by winter warming might increase the activities of soil enzymes related with nitrogen transformation and further stimulate the process of wintertime nitrogen transformation in soils of the subalpine forest.

  5. Characterization of Atmospheric Nitrate Dynamics in a Sub-Alpine Watershed Using Δ17O and δ15N

    Science.gov (United States)

    Bourgeois, I.; Savarino, J. P.; Clement, J. C.

    2015-12-01

    Remote subalpine ecosystems are usually characterized by nutrient-poor soils (Körner, 2004; Seastedt et al., 2004), making them particularly susceptible to undergo changes due to increased atmospheric N deposition (Vitousek et al., 1997; Preunkert et al., 2003). Using Δ17O, a conserved tracer of atmospheric nitrate (NO3 atm) (Michalski et al., 2004; Tsunogai et al., 2010), and δ15N, indicator of NO3 biological sources (Kendall, 1998; Casciotti et al., 2009), we measured the seasonal variations of NO3 atm stable isotopic composition and concentration in several streams and soils originating from two sub-alpine watersheds in the French Alps. Our objective was to investigate whether or not NO3 atm impacts the soil N biogeochemical cycle by increasing nutrients availability for plants and bacteria. We coupled streams and soils measurements with snow-pits sampling and aerosols collection at the Lautaret Pass, to better emphasize the correlation between atmospheric deposition, soil retention and watersheds effluents response. Our results reveal that different temporal dynamics govern our study site: stream measurements show that in spring, snowmelt results in a NO3 atm impulse, accounting for ca. 31 % of the total stream NO3 budget; on the opposite in autumn, NO3 atm accounts only for ca. 3 % of the total stream NO3 budget, highlighting the presence of a NO3 bacterial pool (nitrification). We also inferred from the observed Δ17O variations two distinct phenomena in the spring/summer season: a fast snow run-off and a slower snow-water percolation. The later is believed to affect most the soil N cycle as it directly increases available NO3. Measured soil leachates and extracts confirm this hypothesis and point out the potential importance of anthropogenic N deposition as on average 7 to 10 % of the soil solutions NO3 derives directly from the atmosphere.

  6. Significant increase in ecosystem C can be achieved with sustainable forest management in subtropical plantation forests.

    Science.gov (United States)

    Wei, Xiaohua; Blanco, Juan A

    2014-01-01

    Subtropical planted forests are rapidly expanding. They are traditionally managed for intensive, short-term goals that often lead to long-term yield decline and reduced carbon sequestration capacity. Here we show how it is possible to increase and sustain carbon stored in subtropical forest plantations if management is switched towards more sustainable forestry. We first conducted a literature review to explore possible management factors that contribute to the potentials in ecosystem C in tropical and subtropical plantations. We found that broadleaves plantations have significantly higher ecosystem C than conifer plantations. In addition, ecosystem C increases with plantation age, and reaches a peak with intermediate stand densities of 1500-2500 trees ha⁻¹. We then used the FORECAST model to simulate the regional implications of switching from traditional to sustainable management regimes, using Chinese fir (Cunninghamia lanceolata) plantations in subtropical China as a study case. We randomly simulated 200 traditional short-rotation pure stands and 200 sustainably-managed mixed Chinese fir--Phoebe bournei plantations, for 120 years. Our results showed that mixed, sustainably-managed plantations have on average 67.5% more ecosystem C than traditional pure conifer plantations. If all pure plantations were gradually transformed into mixed plantations during the next 10 years, carbon stocks could rise in 2050 by 260.22 TgC in east-central China. Assuming similar differences for temperate and boreal plantations, if sustainable forestry practices were applied to all new forest plantation types in China, stored carbon could increase by 1,482.80 TgC in 2050. Such an increase would be equivalent to a yearly sequestration rate of 40.08 TgC yr⁻¹, offsetting 1.9% of China's annual emissions in 2010. More importantly, this C increase can be sustained in the long term through the maintenance of higher amounts of soil organic carbon and the production of timber products

  7. Significant increase in ecosystem C can be achieved with sustainable forest management in subtropical plantation forests.

    Directory of Open Access Journals (Sweden)

    Xiaohua Wei

    Full Text Available Subtropical planted forests are rapidly expanding. They are traditionally managed for intensive, short-term goals that often lead to long-term yield decline and reduced carbon sequestration capacity. Here we show how it is possible to increase and sustain carbon stored in subtropical forest plantations if management is switched towards more sustainable forestry. We first conducted a literature review to explore possible management factors that contribute to the potentials in ecosystem C in tropical and subtropical plantations. We found that broadleaves plantations have significantly higher ecosystem C than conifer plantations. In addition, ecosystem C increases with plantation age, and reaches a peak with intermediate stand densities of 1500-2500 trees ha⁻¹. We then used the FORECAST model to simulate the regional implications of switching from traditional to sustainable management regimes, using Chinese fir (Cunninghamia lanceolata plantations in subtropical China as a study case. We randomly simulated 200 traditional short-rotation pure stands and 200 sustainably-managed mixed Chinese fir--Phoebe bournei plantations, for 120 years. Our results showed that mixed, sustainably-managed plantations have on average 67.5% more ecosystem C than traditional pure conifer plantations. If all pure plantations were gradually transformed into mixed plantations during the next 10 years, carbon stocks could rise in 2050 by 260.22 TgC in east-central China. Assuming similar differences for temperate and boreal plantations, if sustainable forestry practices were applied to all new forest plantation types in China, stored carbon could increase by 1,482.80 TgC in 2050. Such an increase would be equivalent to a yearly sequestration rate of 40.08 TgC yr⁻¹, offsetting 1.9% of China's annual emissions in 2010. More importantly, this C increase can be sustained in the long term through the maintenance of higher amounts of soil organic carbon and the production

  8. Pheno-anomalies of sub-alpine Vaccinium heaths in response to climatic variations

    Science.gov (United States)

    Puppi, Giovanna; Monti, Alessandra; Bonafede, Fausto; Vignodelli, Michele; Zanotti, Anna Letizia

    2014-05-01

    reduction in seed production and could have therefore be disadvantaged in turn-over. This hypothesis is consistent with the results on vegetation changes: in fact, the comparison of the actual vegetation with the historical observations in the same sites, shows a reduction of herb (Hemicryptophytes) diversity and cover in time. It is noteworthy that many of the declining species flower in the driest and hottest weeks of the year. In a climate-warming scenario, the low extension of these sub-alpine islands of the Apennines leads to a high extinction risk of the most sensible species. So, the monitoring of this vulnerable vegetation type seems necessary in order to detect the current trends and should be continued in the future. Puppi and Speranza 1980, Arch. Bot. Biogeogr. Ital. 56(3/4) Puppi et al. 1994, Fitosociologia 26: 63-79

  9. Impact of land use change on soil organic matter dynamics in subalpine grassland

    Science.gov (United States)

    Meyer, Stefanie; Leifeld, Jens; Bahn, Michael; Fuhrer, Jürg

    2010-05-01

    Information regarding the response of soil organic matter (SOM) in soils to past and expected future land use changes in the European Alps is scarce. Understanding this response requires knowledge of size and residence times of SOM fractions with distinct stabilities. In order to quantify differences between types of land use in the amount, distribution and turnover rates of soil organic carbon (SOC) in subalpine grassland soils, we used soil aggregate and SOM density fractionation in combination with 14C dating. Samples were taken along gradients of different types of land use from meadow (M) to pasture (P) and to abandoned grassland (A) in the Stubai Valley and in the Matsch Valley. Sampling sites in both areas were located at equal altitude (1880 m and 1820 m, respectively) with the same parent material and soil type, but the Matsch Valley receives 400-500 mm less annual rainfall. SOC stocks in the top 10 cm were 2.47 ± 0.32 (M), 2.75 ± 0.32 (P), and 2.50 ± 0.31 kg C/m2 (A) in the Stubai Valley and 2.25 ± 0.14 (M), 3.45 ± 0.22 (P), 3.16 ± 0.27 kg C/m2(A) in the Matsch Valley. Three aggregate size classes were separated by wet sieving: 2 mm. The light floating fraction (wPOM, ρ >1 g/cm3) was included in the analysis. Free (f-) and occluded particulate organic matter (oPOM) were isolated from each aggregate size class (ρ >1.6 g/cm3). At both locations, more than 80% of SOC was stored in small (0.25-2 mm) and large (>2 mm) macroaggregates, but no trend in relation to the different types of land use could be detected. The fraction of C in fPOM and in oPOM in all aggregate size classes was highest for soil from abandoned grasslands. The bulk soil of the abandoned site in the Stubai Valley showed a significantly higher share of fPOM-C and oPOM-C and a higher amount of wPOM-C as compared to the soil from managed grassland, whereas in the Matsch Valley pasture soil had a significantly higher wPOM-C content. At both sites, 13C natural abundance analyses revealed

  10. Autotrophic and Heterotrophic Controls over Winter Soil Carbon Cycling in a Subalpine Forest Ecosystem

    Science.gov (United States)

    Monson, R. K.; Scott-Denton, L. E.; Lipson, D. A.; Weintrub, M. N.; Rosenstiel, T. N.; Schmidt, S. K.; Williams, M. W.; Burns, S. P.; Delany, A. E.; Turnipseed, A. A.

    2005-12-01

    that interannual variation in winter ecosystem respiration is positively correlated to interannual variation in the spring snow depth. Years with a with a deeper spring snow pack exhibited higher soil temperatures, and concomitantly higher soil respiration rates. Given the recently reported decadal-scale trend in decreasing snow pack in the Western U.S., which is coupled to warm climate anomalies, our observations indicate the potential for higher wintertime soil carbon sequestration due to lower winter ecosystem respiration rates in subalpine forests. Our studies of processes beneath the winter snow pack demonstrate that contrary to previous assumptions, winter biogeochemical processing of soil organic matter is an important component of ecosystem carbon budgets. Despite low temperatures and an inactive plant rhizosphere, winter microbial communities and exoenzymes appear to be active, carbon substrates appear to be in relatively high abundance and soil respiration rates appear to be sensitive to seasonal and interannual winter climate variability.

  11. Use of passive UAS imaging to measure biophysical parameters in a southern Rocky Mountain subalpine forest

    Science.gov (United States)

    Caldwell, M. K.; Sloan, J.; Mladinich, C. S.; Wessman, C. A.

    2013-12-01

    Unmanned Aerial Systems (UAS) can provide detailed, fine spatial resolution imagery for ecological uses not otherwise obtainable through standard methods. The use of UAS imagery for ecology is a rapidly -evolving field, where the study of forest landscape ecology can be augmented using UAS imagery to scale and validate biophysical data from field measurements to spaceborne observations. High resolution imagery provided by UAS (30 cm2 pixels) offers detailed canopy cover and forest structure data in a time efficient and inexpensive manner. Using a GoPro Hero2 (2 mm focal length) camera mounted in the nose cone of a Raven unmanned system, we collected aerial and thermal data monthly during the summer 2013, over two subalpine forests in the Southern Rocky Mountains in Colorado. These forests are dominated by lodgepole pine (Pinus ponderosae) and have experienced insect-driven (primarily mountain pine beetle; MPB, Dendroctonus ponderosae) mortality. Objectives of this study include observations of forest health variables such as canopy water content (CWC) from thermal imagery and leaf area index (LAI), biomass and forest productivity from the Normalized Difference Vegetation Index (NDVI) from UAS imagery. Observations were, validated with ground measurements. Images were processed using a combination of AgiSoft Photoscan professional software and ENVI remote imaging software. We utilized the software Leaf Area Index Calculator (LAIC) developed by Córcoles et al. (2013) for calculating LAI from digital images and modified to conform to leaf area of needle-leaf trees as in Chen and Cihlar (1996) . LAIC uses a K-means cluster analysis to decipher the RGB levels for each pixel and distinguish between green aboveground vegetation and other materials, and project leaf area per unit of ground surface area (i.e. half total needle surface area per unit area). Preliminary LAIC UAS data shows summer average LAI was 3.8 in the most dense forest stands and 2.95 in less dense

  12. A recalcitrant plantation colony : Dominica, 1880-1946

    Directory of Open Access Journals (Sweden)

    Cecilia Green

    1999-07-01

    Full Text Available Study of the class and gender dialectics in Dominica during one of its boom-bust cycles of plantation economy. This cycle encompassed the state sponsorship and rise and decline of the lime industry and planter class; the subsequent coming into prominence on the peasantry in Dominica's political economy and in Colonial Office policy; the masculinist recoding of peasant proprietorship and production forms; and shifting roles and agency of women.

  13. Energy plantation for solving the crisis of fuel and energy

    Energy Technology Data Exchange (ETDEWEB)

    Singhal, O.P.

    1985-10-01

    Concentrated efforts are required for achieving better social foresty in rural areas of India. There are a large number of tree species that can be considered for energy plantations. Some of the fuel wood plants are described: subabul, eucalyptus, agathi, babul, ber, casuarina, imli, karanji, pardeshibabul, siris, jamun, and neem. Carbohydrate plants contain sugar and starch and serve as the source of energy in the form of food and fuel. The latex of some plants can be processed as fuel oil. (Refs. 29).

  14. Sampling plantations to determine white-pine weevil injury

    Science.gov (United States)

    Robert L. Talerico; Robert W., Jr. Wilson

    1973-01-01

    Use of 1/10-acre square plots to obtain estimates of the proportion of never-weeviled trees necessary for evaluating and scheduling white-pine weevil control is described. The optimum number of trees to observe per plot is estimated from data obtained from sample plantations in the Northeast and a table is given. Of sample size required to achieve a standard error of...

  15. Investment appraisal of a poplar plantation aged 42 years

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    Keča Ljiljana

    2013-01-01

    Full Text Available Commercial profitability of poplar cultivation was analyzed in an artificial poplar plantation in Serbia. The aim of this study was to validate the invested financial means in the artificial poplar plantation, on the basis of the analysis of costs and receipts during a 42-year rotation, on alluvial semigley, at a discount rate of 12%. Methods of dynamic investment calculation (net present value - NPV, internal rate of return - IRR, benefit-cost method - B/C and payback period - PBP were used. The investigated plantations were established from Populus x euramericana cl. I-214, with a planting spacing of 6 x 3 m. At the calculation discount rate of 12%, the project for the production cycle of 42 years was not cost-effective from the economic aspect. The discount rate of 6% can be accepted in the studied plot because of the better site (alluvial semigley, but the oldness of the stand is unfavourable. For the studied sample plot, IRR was 5.51 %. B/C at r=12% in the study compartment was 0.24. The analysis shows that PBP is practically unacceptable for the investor at the discount rate of 6%. In practice, it is necessary to improve the position of producers in getting financial means for investment in poplar cultivation, so as to stimulate the establishment of artificial poplar plantations, especially in the private sector (on private land. [Projekat Ministarstva nauke Republike Srbije, br. TR 37008, TR 31041 and Value chain of non-wood forest products and its role in development of forestry sector in Serbia

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

    NARCIS (Netherlands)

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

    2006-01-01

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

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

    Science.gov (United States)

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

    2010-01-01

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

  18. Nitrogen-Fixing Bacteria in Eucalyptus globulus Plantations

    Science.gov (United States)

    da Silva, Marliane de Cássia Soares; Paula, Thiago de Almeida; Moreira, Bruno Coutinho; Carolino, Manuela; Cruz, Cristina; Bazzolli, Denise Mara Soares; Silva, Cynthia Canedo; Kasuya, Maria Catarina Megumi

    2014-01-01

    Eucalypt cultivation is an important economic activity worldwide. In Portugal, Eucalyptus globulus plantations account for one-third of the total forested area. The nutritional requirements of this crop have been well studied, and nitrogen (N) is one of the most important elements required for vegetal growth. N dynamics in soils are influenced by microorganisms, such as diazotrophic bacteria (DB) that are responsible for biological nitrogen fixation (BNF), so the aim of this study was to evaluate and identity the main groups of DB in E. globulus plantations. Samples of soil and root systems were collected in winter and summer from three different Portuguese regions (Penafiel, Gavião and Odemira). We observed that DB communities were affected by season, N fertilization and moisture. Furthermore Bradyrhizobium and Burkholderia were the most prevalent genera in these three regions. This is the first study describing the dynamic of these bacteria in E. globulus plantations, and these data will likely contribute to a better understanding of the nutritional requirements of eucalypt cultivation and associated organic matter turnover. PMID:25340502

  19. Integrated Bali Cattle Development Model Under Oil Palm Plantation

    Directory of Open Access Journals (Sweden)

    Rasali Hakim Matondang

    2015-09-01

    Full Text Available Bali cattle have several advantages such as high fertility and carcass percentage, easy adaptation to the new environment as well. Bali cattle productivity has not been optimal yet. This is due to one of the limitation of feed resources, decreasing of grazing and agricultural land. The aim of this paper is to describe Bali cattle development integrated with oil palm plantations, which is expected to improve productivity and increase Bali cattle population. This integration model is carried out by raising Bali cattle under oil palm plantation through nucleus estate scheme model or individual farmers estates business. Some of Bali cattle raising systems have been applied in the integration of palm plantation-Bali cattle. One of the intensive systems can increase daily weight gain of 0.8 kg/head, calfcrop of 35% per year and has the potency for industrial development of feed and organic fertilizer. In the semi-intensive system, it can improve the production of oil palm fruit bunches (PFB more than 10%, increase harvested-crop area to 15 ha/farmer and reduce the amount of inorganic fertilizer. The extensive system can produce calfcrop ³70%, improve ³30% of PFB, increase business scale ³13 cows/farmer and reduce weeding costs ³16%. Integrated Bali cattle development may provide positive added value for both, palm oil business and cattle business.

  20. Fiscal and Monetary Policy for The Development of Indonesian Plantation

    Directory of Open Access Journals (Sweden)

    Suharyadi Suharyadi

    2011-09-01

    Full Text Available The global monetary crisis in 2007-2008 and the focus of development on climate changesmake it important to promote a healthy economic growth based on the local resources, Theeconomic crisis, which has slowed down the economic growth and has caused job losseswhich result in increasing unemployment and poverty, should alter the focus of Indonesianeconomic development in the future to be based on renewable and sustainable local resources.Indonesia is an agricultural and maritime country so these two aspects should be thecore of the growth. In agricultural culture, plantation sector is the source of sustainable economicgrowth because of its geographical, demographic, and cultural potentials. The problemsin plantation sector are the low growth of areas and productivity as well as its limitedend-products. The research findings indicated that in order to increase areas, there should bea guarantee on investment, interest rate, and little retribution or good governance. To increaseproductivity, we need a guarantee on fertilizer price, interest rate, and wages, as wellas pricing factors to avoid market distortion. This is very important relating to the economicstimulus policy which is essential to revitalize from the economic doom in the future.Keywords: plantation sector, area, productivity, investment, interest rate, and wages

  1. Pruning in poplar plantations by mechanized device Stihl HT-75

    Directory of Open Access Journals (Sweden)

    Danilović Milorad

    2009-01-01

    Full Text Available The effects of branch pruning device Stihl HT-75 were researched on sample plots in FA Kupinovo and FA Klenak, in poplar plantations of Populus×euramericana 'I-214', Populus×euramericana 'M1' and Populus deltoides of different planting spaces and different ages. The analysed factors were: pruning method, site conditions, number of pruned branches, pruning height, branch diameter, etc. Time measurement was performed by the flow method, and the required number of measurements was calculated by variation statistics. The results of the analysis of variance show the statistical significance of the differences between pruning times of different clone species, different planting spaces and different plantation ages. The results of the analysis of variance and statistical tests show that there are no statistically significant differences between the average time of poplar pruning in plantations of the same age and different planting spaces. The correlation of branch pruning time and the number of pruned branches is represented by the power function model, which according to the results of the regression analyses, is the best representation of the nature of this dependence. Exponential function represents the correlation of the average diameter of pruned branches and the time of pruning. Also, there is a correlation of the average diameter of pruned branches and fuel consumption. Pruning time of poplar trees increases with the increase of the average diameter of pruned branches.

  2. THE Eucalyptus sp. AGE PLANTATIONS INFLUENCING THE CARBON STOCKS

    Directory of Open Access Journals (Sweden)

    Charlote Wink

    2013-06-01

    Full Text Available http://dx.doi.org/10.5902/198050989279The tree growth and biomass accumulation, as well as the maintenance of forest residue at the soil surface can act in the removal of carbon from the atmosphere through the cycling process of plant material. The objective was to study the influence of Eucalyptus sp. Plantations with 20, 44 and 240 months of age on the variation of carbon in soil and biomass. The carbon in the soil depth was determined by CHNS auto-analyzer and carbon in the vegetation was determined by the biomass in each forest, considering a factor of 0.45 of the dry mass. We determined the density and particle size distribution of soil. For the comparison between plantations, there was analysis of variance and comparison of means of carbon in vegetation and soil, considering the 5% level of probability. The carbon content and stock in the soil were low, indicating that a natural feature of the category of Paleuldt, or the growth of eucalyptus forests, replacing the field native vegetation did not aggregate a significant increase in the carbon. Although, there was a significant increase carbon in aboveground biomass. It includes forest biomass and litter. So, despite the values ​​of carbon stocks are low, it identified a greater average total in the soil compared to the stock aboveground. Furthermore, this increase aboveground (tree and litter compartments can be considered significant between the eucalyptus plantations of different ages.

  3. Ergonomics observation: Harvesting tasks at oil palm plantation.

    Science.gov (United States)

    Ng, Yee Guan; Shamsul Bahri, Mohd Tamrin; Irwan Syah, Md Yusoff; Mori, Ippei; Hashim, Zailina

    2014-01-01

    Production agriculture is commonly associated with high prevalence of ergonomic injuries, particularly during intensive manual labor and during harvesting. This paper intends to briefly describe an overview of oil palm plantation management highlighting the ergonomics problem each of the breakdown task analysis. Although cross-sectional field visits were conducted in the current study, insight into past and present occupational safety and health concerns particularly regarding the ergonomics of oil palm plantations was further exploited. Besides discussion, video recordings were extensively used for ergonomics analysis. The unique commodity of oil palm plantations presents significantly different ergonomics risk factors for fresh fruit bunch (FFB) cutters during different stages of harvesting. Although the ergonomics risk factors remain the same for FFB collectors, the intensity of manual lifting increases significantly with the age of the oil palm trees-weight of FFB. There is urgent need to establish surveillance in order to determine the current prevalence of ergonomic injuries. Thereafter, ergonomics interventions that are holistic and comprehensive should be conducted and evaluated for their efficacy using approaches that are integrated, participatory and cost-effective.

  4. ECONOMIC EVALUATION OF Eucalyptus grandis PLANTATION FOR CELLULOSE PRODUCTION

    Directory of Open Access Journals (Sweden)

    Antonio Donizette de Oliveira

    2008-03-01

    Full Text Available The aims of this research were: to analyze the economic feasibility of planting eucalyptus for producing wood pulp,considering various site index and two spacings; to analyze the economic effects regarding the profitability of the forest activity indifferent distances from the industry and changes on discount rate, wood price, transportation costs, minimum profitable diameter oflogs and the length of the logs. A biometric model for making wood volume prognosis was developed, using data of a trial ofEucalyptus grandis stands 19 and 103 months old. The prognosis started at the age zero, considering logs of 2.5 and 6.0 m of lenghtand the minimum diameter varying from 4 to 10 cm, in intervals of 2 cm. Net Present Worth (NPW was used as the economic decisioncriterium, considering an infinite horizon. The main conclusions were: reducing the minimum profitable diameter and the length ofthe logs are good strategies to increase wood utilization and profit; plantations located in less productive lands are economicallyunfeasible; the cost of transportation has significant effect on the profitability of the forest activity and must be analyzed carefully atthe moment of defining the location of new plantations; small variations on wood sales price may cause big alterations on theprofitability of the forest activity, suggesting that the improvement of the wood quality together with other decisions that may increasewood price are alternatives that may render the plantations in less productive areas profitable.

  5. Developmental Trends of Black Spruce Fibre Attributes in Maturing Plantations

    Directory of Open Access Journals (Sweden)

    Peter F. Newton

    2016-01-01

    Full Text Available This study assessed the temporal developmental patterns of commercially relevant fibre attributes (tracheid length and diameters, wall thickness, specific surface area, wood density, microfibril angle, fibre coarseness, and modulus of elasticity and their interrelationships within maturing black spruce (Picea mariana (Mill. B.S.P. plantations. A size-based stratified random sample procedure within 5 semimature plantations located in the Canadian Boreal Forest Region was used to select 50 trees from which radial cross-sectional xylem sequences at breast-height (1.3 m were cut and analyzed. Statistically, the graphical and linear correlation analyses indicated that the attributes exhibited significant (p≤0.05 relationships among themselves and with morphological tree characteristics. Relative variation of each annually measured attribute declined with increasing size class (basal area quintile. The transitional shifts in temporal correlation patterns occurring at the time of approximate crown closure where suggestive of intrinsic differences in juvenile and mature wood formation processes. The temporal cumulative development patterns of all 8 of the annually measured attributes varied systematically with tree size and exhibited the most rapid rates of change before the trees reached a cambial age of 20 years. At approximately 50 years after establishment, plantation mean attribute values were not dissimilar from those reported for more mature natural-origin stands.

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2006-12-15

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

  7. Comparison of insect biodiversity between organic and conventional plantations in Kodagu, Karnataka, India

    Directory of Open Access Journals (Sweden)

    S. Mone

    2014-08-01

    Full Text Available We undertook a comparative analysis of ground insects and fruit eating butterflies on 29 different plantations in Kodagu District of Karnataka which is one of the rich biodiversity zones of the Western Ghats. These included organic and conventional coffee and cardamom plantations using different levels of chemical fertilizers and pesticides. A total number of 457 ground insect species were collected using pit-fall traps which included 92 species of ants and 123 species of beetles, among other insect taxa that we measured. Similarly, 25 species of butterflies belonging to the family Nymphalidae were collected using bait traps. We found a clear negative effect on the ground insect species diversity (Shannon index and evenness (Shannon evenness index in pesticide treated plantations as compared to the organic plantations. A similar negative effect was observed for butterfly diversity in plantations using pesticides. Our results corroborate the value of organic plantations in supporting higher levels of biodiversity.

  8. Variation of Soil Bacterial Communities in a Chronosequence of Rubber Tree (Hevea brasiliensis) Plantations

    OpenAIRE

    Zhou, Yu-Jie; Li, Jian-Hua; Ross Friedman, Cynthia; Wang, Hua-Feng

    2017-01-01

    Regarding rubber tree plantations, researchers lack a basic understanding of soil microbial communities; specifically, little is known about whether or not soil microbial variation is correlated with succession in these plantations. In this paper, we used high-throughput sequencing of the 16S rRNA gene to investigate the diversity and composition of the soil bacterial communities in a chronosequence of rubber tree plantations that were 5, 10, 13, 18, 25, and 30 years old. We determined that: ...

  9. Slipping through the cracks: rubber plantation is unsuitable breeding habitat for frogs in Xishuangbanna, China.

    Directory of Open Access Journals (Sweden)

    Jocelyn E Behm

    Full Text Available Conversion of tropical forests into agriculture may present a serious risk to amphibian diversity if amphibians are not able to use agricultural areas as habitat. Recently, in Xishuangbanna Prefecture, Yunnan Province - a hotspot of frog diversity within China - two-thirds of the native tropical rainforests have been converted into rubber plantation agriculture. We conducted surveys and experiments to quantify habitat use for breeding and non-breeding life history activities of the native frog species in rainforest, rubber plantation and other human impacted sites. Rubber plantation sites had the lowest species richness in our non-breeding habitat surveys and no species used rubber plantation sites as breeding habitat. The absence of breeding was likely not due to intrinsic properties of the rubber plantation pools, as our experiments indicated that rubber plantation pools were suitable for tadpole growth and development. Rather, the absence of breeding in the rubber plantation was likely due to a misalignment of breeding and non-breeding habitat preferences. Analyses of our breeding surveys showed that percent canopy cover over pools was the strongest environmental variable influencing breeding site selection, with species exhibiting preferences for pools under both high and low canopy cover. Although rubber plantation pools had high canopy cover, the only species that bred in high canopy cover sites used the rainforest for both non-breeding and breeding activities, completing their entire life cycle in the rainforest. Conversely, the species that did use the rubber plantation for non-breeding habitat preferred to breed in low canopy sites, also avoiding breeding in the rubber plantation. Rubber plantations are likely an intermediate habitat type that 'slips through the cracks' of species habitat preferences and is thus avoided for breeding. In summary, unlike the rainforests they replaced, rubber plantations alone may not be able to support

  10. Components of Soil Respiration and its Monthly Dynamics in Rubber Plantation Ecosystems

    OpenAIRE

    Zhixiang Wu; Limin Guan; Bangqian Chen; Chuan Yang; Guoyu Lan; Guishui Xie; Zhaode Zhou

    2014-01-01

    Aim: Our objective was to quantify four components and study effect factors of soil respiration in rubber plantation ecosystems. Providing the basic data support for the establishment of the trade of rubber plantation ecosystem carbon source/sink. Methods: We used Li-6400 (IRGA, Li-COR) to quantitate four components of soil respiration in rubber plantation ecosystems at different ages. Soil respiration can be separated as four components: heterotrophic respiration (Rh), Respiration of roots (...

  11. Above-ground sulfur cycling in adjacent coniferous and deciduous forest and watershed sulfur retention in the Georgia Piedmont, U.S.A.

    Science.gov (United States)

    Cappellato, R.; Peters, N.E.; Meyers, T.P.

    1998-01-01

    Atmospheric deposition and above-ground cycling of sulfur (S) were evaluated in adjacent deciduous and coniferous forests at the Panola Mountain Research Watershed (PMRW), Georgia U.S.A. Total atmospheric S deposition (wet plus dry) was 12.9 and 12.7 kg ha-1 yr-1 for the deciduous and coniferous forests, respectively, from October 1987 through November 1989. Dry deposition contributes more than 40% to the total atmospheric S deposition, and SO2 is the major source (~55%) of total dry S deposition. Dry deposition to these canopies is similar to regional estimates suggesting that 60-km proximity to emission sources does not noticeably impact dry deposition at PMRW. Below-canopy S fluxes (throughfall plus stemflow) in each forest are 37% higher annually in the deciduous forest than in the coniferous forest. An excess in below-canopy S flux in the deciduous forest is attributed to leaching and higher dry deposition than in the coniferous forest. Total S deposition to the forest floor by throughfall, stemflow and litterfall was 2.4 and 2.8 times higher in the deciduous and coniferous forests, respectively, than annual S growth requirement for foliage and wood. Although A deposition exceeds growth requirement, more than 95% of the total atmospheric S deposition was retained by the watershed in 1988 and 1989. The S retention at PMRW is primarily due to SO2+4 adsorption by iron oxides and hydroxides in watershed soils. The S content in while oak and loblolly pine boles have increased more than 200% in the last 20 yr, possibly reflecting increases in emissions.

  12. Prospects of Applying Feed Processing Technologies Based on Industrial Plantation

    Directory of Open Access Journals (Sweden)

    Simon Petrus Ginting

    2012-06-01

    Full Text Available The potency of plantation sectors (palm oil, sugar cane and cacao as alternative feed resources for ruminants has been acknowledged since 20 – 25 years ago. However, the level of utilization of these feeds in small ruminant production system has been very low and sporadic. The typical chemical and physical characteristics of most of those feedstuffs required some steps of processing in order to improve their nutritional quality and to ease their handling. Small ruminants, like sheep and goats have relatively higher metabolic energy requirement per kg BW and anatomically have lower gut capacity to process lignocelluose materials compared to large ruminants. It is, therefore, these animals nutritionally face more constraints in handling lignocellulose and bulky materials mostly found in industrial by products or crop-residues from plantations. Physical processes (chopping, phyiscal separation, hydrothermal, chemical processes (ammoniation, hydrolyses and oxidative treatments and bio-conversions (fermentation, ensiling have been recommended as alternative technologies in maximizing the utilization of those feedstuffs for small ruminant animals. The principal mechanisms of those treatments are: (i breaking the linkages between structural carbohydrate and lignin so that it could be easily digested by the animal enzyme systems and (ii preserving the material from being spoilage due to its high moisture content or for feed stocking purposes. Priorities for choosing the most effective processing technology for implementation or adoption is depent largely on the scale of feed production. Ammoniation, chopping, physical separation, ensiling or bio-conversion are several technologies mostly recommended for small scale operation in situ. These alternative technologies should be able to be adopted by small-holders living around the plantation area. The commercial or large scale feed production could be implemented by the plantation industry by giving high

  13. Variation of Soil Bacterial Communities in a Chronosequence of Rubber Tree (Hevea brasiliensis Plantations

    Directory of Open Access Journals (Sweden)

    Yu-Jie Zhou

    2017-05-01

    Full Text Available Regarding rubber tree plantations, researchers lack a basic understanding of soil microbial communities; specifically, little is known about whether or not soil microbial variation is correlated with succession in these plantations. In this paper, we used high-throughput sequencing of the 16S rRNA gene to investigate the diversity and composition of the soil bacterial communities in a chronosequence of rubber tree plantations that were 5, 10, 13, 18, 25, and 30 years old. We determined that: (1 Soil bacterial diversity and composition show changes over the succession stages of rubber tree plantations. The diversity of soil bacteria were highest in 10, 13, and 18 year-old rubber tree plantations, followed by 30 year-old rubber tree plantations, whereas 5 and 25 year-old rubber tree plantations had the lowest values for diversity. A total of 438,870 16S rDNA sequences were detected in 18 soil samples from six rubber tree plantations, found in 28 phyla, 66 classes, 139 orders, 245 families, 355 genera, and 645 species, with 1.01% sequences from unclassified bacteria. The dominant phyla were Acidobacteria, Proteobacteria, Chloroflexi, Actinobacteria, and Verrucomicrobia (relative abundance large than 3%. There were differences in soil bacterial communities among different succession stages of rubber tree plantation. (2 Soil bacteria diversity and composition in the different stages was closely related to pH, vegetation, soil nutrient, and altitude, of which pH, and vegetation were the main drivers.

  14. Variation of Soil Bacterial Communities in a Chronosequence of Rubber Tree (Hevea brasiliensis) Plantations.

    Science.gov (United States)

    Zhou, Yu-Jie; Li, Jian-Hua; Ross Friedman, Cynthia; Wang, Hua-Feng

    2017-01-01

    Regarding rubber tree plantations, researchers lack a basic understanding of soil microbial communities; specifically, little is known about whether or not soil microbial variation is correlated with succession in these plantations. In this paper, we used high-throughput sequencing of the 16S rRNA gene to investigate the diversity and composition of the soil bacterial communities in a chronosequence of rubber tree plantations that were 5, 10, 13, 18, 25, and 30 years old. We determined that: (1) Soil bacterial diversity and composition show changes over the succession stages of rubber tree plantations. The diversity of soil bacteria were highest in 10, 13, and 18 year-old rubber tree plantations, followed by 30 year-old rubber tree plantations, whereas 5 and 25 year-old rubber tree plantations had the lowest values for diversity. A total of 438,870 16S rDNA sequences were detected in 18 soil samples from six rubber tree plantations, found in 28 phyla, 66 classes, 139 orders, 245 families, 355 genera, and 645 species, with 1.01% sequences from unclassified bacteria. The dominant phyla were Acidobacteria, Proteobacteria, Chloroflexi, Actinobacteria, and Verrucomicrobia (relative abundance large than 3%). There were differences in soil bacterial communities among different succession stages of rubber tree plantation. (2) Soil bacteria diversity and composition in the different stages was closely related to pH, vegetation, soil nutrient, and altitude, of which pH, and vegetation were the main drivers.

  15. Homogenization and impoverishment of taxonomic and functional diversity of ants in Eucalyptus plantations.

    Science.gov (United States)

    Martello, Felipe; de Bello, Francesco; Morini, Maria Santina de Castro; Silva, Rogério R; Souza-Campana, Débora Rodriges de; Ribeiro, Milton Cezar; Carmona, Carlos P

    2018-02-19

    Despite its negative impacts on the environment and biodiversity, tree plantations can contribute to biodiversity conservation in fragmented landscapes, as they harbor many native species. In this study, we investigated the impact of Eucalyptus plantations on the taxonomic and functional diversity of ant communities, comparing ant communities sampled in managed and unmanaged (abandoned for 28 years) Eucalyptus plantations, and native Atlantic rain forests. Eucalyptus plantations, both managed and unmanaged, reduced the functional diversity and increased the similarity between ant communities leading to functional homogenization. While communities in managed plantations had the lowest values of both taxonomic and functional ant diversities, ant communities from unmanaged plantations had similar values of species richness, functional redundancy and Rao's Q compared to ant communities from forest patches (although functional richness was lower). In addition, communities in unmanaged Eucalyptus plantations were taxonomically and functionally more similar to communities located in managed plantations, indicating that Eucalyptus plantations have a severe long-term impact on ant communities. These results indicate that natural regeneration may mitigate the impact of Eucalyptus management, particularly regarding the functional structure of the community (α diversity), although it does not attenuate the effects of long term homogenization in community composition (β diversity).

  16. The most important parasitic and saprophytic fungi in Austrian pine and Scots pine plantations in Serbia

    Directory of Open Access Journals (Sweden)

    Karadžić Dragan

    2008-01-01

    Full Text Available In Austrian pine plantations in Serbia, the greatest damage is caused by the fungi Mycosphaerella pini, Sphaeropsis sapinea, Cenangium ferruginosum, Germmeniella abietina (in the mountain regions and occasionally Armillaria spp., Lophodermium spp. (seditiosum, conigenum, pinastri and Cyclaneusma niveum. In Scots pine plantations, the greatest damage is caused by the fungi Heterobasidion annosum (especially in plantations on sandy soils, Armillaria spp, Lophodermium seditiosum, L. pinastri, Cyclaneusma minus and Sphaeropsis sapinea. Damage caused by rust fungi (Coleosporium sennecionis, Melampsora pinitorqua and Cronartium flaccidum occurs less frequently. In mountainous regions in Scots pine plantations, great damage is caused by Phacidium infestans, Lophodermella sulcigena and Gremmeniella abietina.

  17. Mapping Deciduous Rubber Plantation Areas and Stand Ages with PALSAR and Landsat Images

    Directory of Open Access Journals (Sweden)

    Weili Kou

    2015-01-01

    Full Text Available Accurate and updated finer resolution maps of rubber plantations and stand ages are needed to understand and assess the impacts of rubber plantations on regional ecosystem processes. This study presented a simple method for mapping rubber plantation areas and their stand ages by integration of PALSAR 50-m mosaic images and multi-temporal Landsat TM/ETM+ images. The L-band PALSAR 50-m mosaic images were used to map forests (including both natural forests and rubber trees and non-forests. For those PALSAR-based forest pixels, we analyzed the multi-temporal Landsat TM/ETM+ images from 2000 to 2009. We first studied phenological signatures of deciduous rubber plantations (defoliation and foliation and natural forests through analysis of surface reflectance, Normal Difference Vegetation Index (NDVI, Enhanced Vegetation Index (EVI, and Land Surface Water Index (LSWI and generated a map of rubber plantations in 2009. We then analyzed phenological signatures of rubber plantations with different stand ages and generated a map, in 2009, of rubber plantation stand ages (≤5, 6–10, >10 years-old based on multi-temporal Landsat images. The resultant maps clearly illustrated how rubber plantations have expanded into the mountains in the study area over the years. The results in this study demonstrate the potential of integrating microwave (e.g., PALSAR and optical remote sensing in the characterization of rubber plantations and their expansion over time.

  18. Stream flow unaffected by Eucalyptus plantation harvesting implicates water use by the native forest streamside reserve

    Directory of Open Access Journals (Sweden)

    Philip J. Smethurst

    2015-03-01

    New hydrological insights: Plantation harvest had little effect on steam flow, despite a 6–11 m rise in water table level under the plantation area. This result suggests that the native forest reserve intercepted groundwater moving laterally between the plantation and the stream. Measured and simulated runoff coefficients were similarly low (5% and 3%, respectively, but simulated removal of the native forest led to an increase to 38%. Therefore, plantation management in this type of landscape is likely to have little impact on stream flows where there is an intact native rainforest reserve beside the stream.

  19. [Relationships between coefficient of variation of diameter and height and competition index of main coniferous trees in Changbai Mountains].

    Science.gov (United States)

    Zhao, Jun-Hui; Kang, Xin-Gang; Zhang, Hui-Dong; Liu, Yan

    2009-08-01

    A total of 1139 trees from 8 clear-cut stands dominated by fir, spruce, and pine in the Changbai Mountains were selected to study the relationships between the coefficient of variation of diameter and height and the competition index of the three main coniferous tree species in the Mountains. For the test tree species, the variation of height vs. diameter class was relatively small, while the variations of diameter and height vs. age class were larger, with the largest coefficient of variation of diameter vs. age class. The traditional height-diameter models could better reflect the real growth of trees, whereas the diameter-age or height-age models were not good enough. Competition was the main factor inducing the variations of tree diameter and height, suggesting that incorporating the competition index to the traditional models of tree growth and height could improve the model accuracy significantly.

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

    Directory of Open Access Journals (Sweden)

    Kumar Munesh

    2009-08-01

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

  1. Simulation of L-band and HH microwave backscattering from coniferous forest stands - A comparison with SIR-B data

    Science.gov (United States)

    Sun, Guo-Qing; Simonett, David S.

    1988-01-01

    SIR-B images of the Mt. Shasta region of northern California are used to evaluate a composite L-band HH backscattering model of coniferous forest stands. It is found that both SIR-B and simulated backscattering coefficients for eight stands studied have similar trends and relations to average tree height and average number of trees per pixel. Also, the dispersion and distribution of simulated backscattering coefficients from each stand broadly match SIR-B data from the same stand. Although the limited quality and quantity of experimental data makes it difficult to draw any strong conclusions, the comparisons indicate that a stand-based L-band HH composite model seems promising for explaining backscattering features.

  2. Occurrence and Distribution of Synthetic Organic Substances in Boreal Coniferous Forest Soils Fertilized with Hygienized Municipal Sewage Sludge

    Directory of Open Access Journals (Sweden)

    Mats Tysklind

    2013-07-01

    Full Text Available The occurrence and distribution of synthetic organic substances following application of dried and granulated (hygienized municipal sewage sludge in Swedish boreal coniferous forests were investigated. Elevated concentrations of triclosan (TCS, polybrominated diphenyl ethers (PBDEs, and polychlorinated biphenyls (PCBs were detected in the humus layer. Concentrations of ethinyl estradiol (EE2, norfloxacin, ciprofloxacin, ofloxacin (FQs, and polyaromatic hydrocarbons (PAHs were not significantly influenced. Maximum concentrations in humus were as follows (in ng/g dry matter: TCS; 778; PBDEs; 25; and PCB7; 16.7. Fertilization did not alter the levels of the substances in mineral soil, ground water, and various types of samples related to air. Further research within this area is needed, including ecotoxicological effects and fate, in order to improve the knowledge regarding the use of sludge as a fertilizing agent. Continuous annual monitoring, with respect to sampling and analysis, should be conducted on the already-fertilized fields.

  3. Do the energy fluxes and surface conductance of boreal coniferous forests in Europe scale with leaf area?

    Science.gov (United States)

    Launiainen, Samuli; Katul, Gabriel G; Kolari, Pasi; Lindroth, Anders; Lohila, Annalea; Aurela, Mika; Varlagin, Andrej; Grelle, Achim; Vesala, Timo

    2016-12-01

    Earth observing systems are now routinely used to infer leaf area index (LAI) given its significance in spatial aggregation of land surface fluxes. Whether LAI is an appropriate scaling parameter for daytime growing season energy budget, surface conductance (G s ), water- and light-use efficiency and surface-atmosphere coupling of European boreal coniferous forests was explored using eddy-covariance (EC) energy and CO 2 fluxes. The observed scaling relations were then explained using a biophysical multilayer soil-vegetation-atmosphere transfer model as well as by a bulk G s representation. The LAI variations significantly alter radiation regime, within-canopy microclimate, sink/source distributions of CO 2 , H 2 O and heat, and forest floor fluxes. The contribution of forest floor to ecosystem-scale energy exchange is shown to decrease asymptotically with increased LAI, as expected. Compared with other energy budget components, dry-canopy evapotranspiration (ET) was reasonably 'conservative' over the studied LAI range 0.5-7.0 m 2 m -2 . Both ET and G s experienced a minimum in the LAI range 1-2 m 2 m -2 caused by opposing nonproportional response of stomatally controlled transpiration and 'free' forest floor evaporation to changes in canopy density. The young forests had strongest coupling with the atmosphere while stomatal control of energy partitioning was strongest in relatively sparse (LAI ~2 m 2 m -2 ) pine stands growing on mineral soils. The data analysis and model results suggest that LAI may be an effective scaling parameter for net radiation and its partitioning but only in sparse stands (LAI energy exchange. In denser forests, any LAI dependency varies with physiological traits such as light-saturated water-use efficiency. The results suggest that incorporating species traits and site conditions are necessary when LAI is used in upscaling energy exchanges of boreal coniferous forests. © 2016 John Wiley & Sons Ltd.

  4. Dynamics of soil organic carbon mineralization in tea plantations converted from farmland at Western Sichuan, China.

    Science.gov (United States)

    Zhu, Renhuan; Zheng, Zicheng; Li, Tingxuan; Zhang, Xizhou; He, Shuqin; Wang, Yongdong; Liu, Tao; Li, Wei

    2017-01-01

    Climate warming and land use change are some of the drivers affecting soil organic carbon (SOC) dynamics. The Grain for Green Project, local natural resources, and geographical conditions have resulted in farmland conversion into tea plantations in the hilly region of Western Sichuan. However, the effect of such land conversion on SOC mineralization remains unknown. In order to understand the temperature sensitivity of SOC decomposition in tea plantations converted from farmland, this study considered the different years (i.e., 2-3, 9-10, and 16-17 years) of tea plantations converted from farmland as the study site, and soil was incubated for 28 days at 15°C, 25°C, and 35°C to measure the soil respiration rate, amount, and temperature coefficient (Q10). Temperature and land use type interactively affected the SOC mineralization rate, and the cumulative amount of SOC mineralization in all the plots was the largest at 35°C. SOC mineralization was greater and more sensitive to temperature changes in the farmland than in the tea plantations. Compared with the control, tea plantation soils showed lower SOC mineralization rate and cumulative mineralization amount. The 16-17-year-old tea plantation with a low SOC mineralization amount and high SOC content revealed the benefits of carbon sequestration enhancement obtained by converting farmland into tea plantations. The first-order kinetic equation described SOC mineralization dynamics well. Farmland conversion into tea plantations appeared to reduce the potentially mineralizable carbon pool, and the age of tea plantations also had an effect on the SOC mineralization and sequestration. The relatively weak SOC mineralization temperature sensitivity of the tea plantation soils suggested that the SOC pool of the tea plantation soils was less vulnerable to warming than that of the control soils.

  5. Subalpine Conifer Seedling Demographics: Species Responses to Climate Manipulations Across an Elevational Gradient at Niwot Ridge, Colorado

    Science.gov (United States)

    Castanha, C.; Germino, M. J.; Torn, M. S.; Ferrenberg, S.; Harte, J.; Kueppers, L. M.

    2010-12-01

    The effect of climate change on future ranges of treeline species is poorly understood. For example, it is not known whether trees will recruit into the alpine, above the current treeline, and whether population-level differences in trees will mediate range shifts. At Niwot Ridge, Colorado, we used common gardens and climate manipulations to test predictions that warming will lead to greater recruitment at and beyond the cold edge of these species ranges, and will reduce recruitment at the warm edge. Seed from local populations of limber pine and Englemann spruce was harvested and reciprocally planted in 3 experimental sites spanning an elevation gradient from lower subalpine forest (10,000’), to the upper subalpine treeline ecotone (11,000’), to the alpine tundra (11,300’). In Fall 2009 seeds were sown into 20 plots at each site. Overhead infrared heaters targeted increases in growing season surface soil temperature of 4-5°C. The heating treatment, which began in October 2009, was crossed with manual watering, which was initiated following snowmelt in 2010. Over the 2010 growing season, we surveyed seedling germination and mortality weekly. Germination began in early May at the forest site, in early June at the krummholz site, and in early July at the alpine site. Depending on the site and plot, heating accelerated germination by 1 to 4 weeks. Seed source elevation, species, and site all affected germination, with effects for the two species also depending on site. At all sites, lower elevation, warm-edge populations had higher germination rates than high-elevation, cool-edge populations, indicating a potential bottleneck for germination of the high elevation seed sources in the adjacent alpine tundra. At all sites, survival was generally higher for pine than for spruce. Watering tended to enhance pine germinant survival while heating tended to depress spruce germinant survival. Our results indicate that the alpine tundra, generally considered an

  6. Estimating productivity of tropical forest plantations by climatic factors

    Energy Technology Data Exchange (ETDEWEB)

    Pandey, D.

    1996-12-31

    This study presents an alternative method of estimating wood production at regional/global levels from tropical plantations based on climatic variables. A generic model for estimating potential yield in tropical plantations was formulated. The model was developed for teak (Tectona grandis L. F.) as a case study. Available data of teak sample plots from India, Myanmar, Indonesia, Nigeria and Ivory Coast, consisting of 153 plots distributed over 38 meteorological stations were used. A new base age invariant site index function was developed and the site index of each plot was estimated. The mean annual volume increment (MAI) of each plot from existing yield tables was then interpolated. Treating MAI at 50 years (rotation age) as potential yield of teak, a model was constructed which could explain about 59% variance of the potential yield. Models constructed for estimating the maximum MAI and the site index of teak explained the variability up to 61% and 57% respectively. The models underestimated the productivity of teak in Indonesia, Nigeria and Ivory Coast. The rainfall and the relative humidity have been identified as the most important climatic variables influencing the growth of teak. The length of the growing season and the temperature of the warmest month of the growing season were found significant in the models. The temperature and the day length (sunshine) have not been found to be the limiting factors for the growth of teak. However, the maximum temperature beyond a certain upper limit has a negative effect on growth. The study indicates that this upper limit is around 33 deg C for teak. The models could be used to forecast the potential yield of the existing as well as planned teak plantations in the tropical region. 109 refs, 15 figs, 11 tabs

  7. Disaster risk assessment at Roburnia Plantation, Mpumalanga, South Africa

    Directory of Open Access Journals (Sweden)

    Rudzani A. Makhado

    2013-03-01

    Full Text Available This study reports about disaster risk assessment undertaken at Roburnia Plantation, Mpumalanga Province, South Africa. Both quantitative and qualitative approaches were followed to collect data. A total of eight experienced foresters and fire fighters were purposively sampled for interview at Roburnia Plantation. A questionnaire survey was also used to collect the data. Risk levels were quantified using the risks equations of Wisner et al. (2004 and the United Nations International Strategy for Disaster Reduction (UNISDR 2002. Data were analysed using descriptive and inferential statistics. Analysis of variance (ANOVA, single factor was also applied. This study found that Roburnia Plantation is highly exposed to fire risks. The mean (± s.d. output from the Wisner risk equation shows that fire is the highest risk at 7.7 ± 0.3, followed by harsh weather conditions at 5.6 ± 0.4 and least by tree diseases, pests and pathogens at 2.3 ± 0.2. Similarly, the mean (± s.d. output from the UNISDR risk equation also shows that fire is the highest risk at 2.9 ± 0.2, followed by harsh weather conditions at 2.2 ± 0.3 and least by tree diseases, pests and pathogens at 1.3 ± 0.2. There was no significant deference in the risk analysis outputs (p = 0.13. This study also found that the number of fire incidents were low during summer, but increased during winter and spring. This variation is mainly due to a converse relationship with rainfall, because the availability of rain moistens the area as well as the fuel. When the area and fuel is moist, fire incidents are reduced, but they increase with a decrease in fuel moisture.

  8. Oil palm plantation effects on water quality in Kalimantan, Indonesia

    Science.gov (United States)

    Carlson, K. M.; Curran, L. M.

    2011-12-01

    Global demand for palm oil has stimulated a 7-fold increase in oil palm (Elaeis guineensis) plantation area in Indonesia since 1990. Expansion will continue as Indonesia plans to double current production by 2020. Oil palm fertilizers, effluent from oil palm mills, and erosion from land clearing and roads threaten river water quality near plantations. These rivers provide essential ecosystem services including water for drinking, cooking, and washing. Robust empirical measurements of plantation expansion impacts on water resources are necessary to discern the effects of agribusiness on local livelihoods and ecosystems. In Ketapang District, West Kalimantan, Indonesian Borneo, we evaluated the effects of land cover change on water quality by assessing water chemistry in streams draining four end-member watersheds ( ~600-1900 ha watershed-1): Logged forest, mixed agro-forest dominated by rubber and upland rice fallows, young oil palm forest (0-5 years), and old oil palm forest (10-15 years). To assess land cover change, we used CLASLite software to derive fractional cover from a time series (1989-2008) of Landsat data. Nearest neighbor classification and post-classification change detection yielded classes including primary forest, logged forest, secondary forest regrowth, smallholder agriculture, and oil palm. Stream water quality (temperature, dissolved oxygen, turbidity, optical chlorphyll, and pH) and quantity (discharge) were quantified with the YSI 6600-V2 sonde. The sonde was deployed in each stream for month-long intervals 2-3 times from 2009-2010. Such extended deployment captures episodic events such as intense storms and allows examination of interdiel dynamics by sampling continuously and at high frequency, every 10 minutes. We find that across the Ketapang District study region (~12,000 km2), oil palm has cleared mostly forests (49%) and agroforests (39%). What are the impacts of such land cover changes on water quality? Compared to forests and

  9. Carbon storage in eucalyptus and pine plantations in South Africa

    CSIR Research Space (South Africa)

    Christie, SI

    1995-11-01

    Full Text Available because total biomass also includes branches, bark, leaves, and roots. Many tree species have been used in planation forests in South Africa. The softwood plantations are predominantly Pinus patula, while the hardwoods are predominantly Eucalyptus... patula Eucalyptus grandis Component 20 years 8 years 7 years Bole wood 70.7 66.6 75.2 Branch wood 10.1 9.4 2.7 Bark 5.9 7.5 7.1 Leaves 1.5 3.6 2.3 Roots 11.5 (13.0) ~ (12.7) a 'Root biomass was not measured but is estimated to constitute 15...

  10. Canopy damage to conifer plantations within a large mixed-severity wildfire varies with stand age

    Science.gov (United States)

    Jonathan R. Thompson; Thomas A. Spies; Keith A. Olsen

    2011-01-01

    The 2002 Biscuit Fire burned at mixed-severities encompassing over 200,000 ha of publicly owned forestland, including more than 8300 ha of conifer plantations. We used pre- and post-fire digital aerial photography to examine how the level of canopy damage varied within these plantations in relation to topography, weather, vegetation-cover, and management history, with...

  11. The socioeconomic impact of the phasing out of plantations in the ...

    African Journals Online (AJOL)

    The socioeconomic impact of the phasing out of plantations in the Western and Southern Cape regions of South Africa. ... Cape, and two near George in the Southern Cape) managed by Mountain to Ocean Forestry (Pty) Ltd (currently Cape Pine Investment Holdings Ltd), among three different plantation stakeholder groups.

  12. Feasibility Analysis of Leaf-Based Moringa oleifera Plantation in the ...

    African Journals Online (AJOL)

    This study examined the profitability and economic feasibility of a leaf-based Moringa production and processing under a plantation system in the Nigerian guinea savannah using the University of Ilorin Moringa Plantation as a case study. To achieve this objective, data on production and processing cost and revenue for the ...

  13. [Effects of stand structure regulation on soil labile organic carbon in Pinus elliottii plantation].

    Science.gov (United States)

    Tan, Gui-Xia; Liu, Yuan-Qiu; Li, Lian-Lian; Liu, Wu; Zan, Yu-Ting; Huo, Bing-Nan; He, Mu-Jiao

    2014-05-01

    Taking 21-year-old Pinus elliottii pure plantation as the control, effects of enrichment planting with broadleaf trees (Liquidambar fornosana) after thinning the conifer trees (P. elliottii) on soil labile organic carbon of different plantations, including 3-year-old, 6-year-old, 9-year-old P. elliottii and 21-year-old P. elliottii-L. fornosana mixed plantations, were investigated. The results showed that the contents of soil dissolved organic carbon (DOC), readily oxidizable organic carbon (ROC), and microbial biomass carbon (MBC) significantly increased in the 6-year-old and 9-year-old plantations compared with those in the 21-year-old P. elliottii pure plantation. Soil labile organic carbon contents in the 21-year-old P. elliottii-L. fornosana mixed plantation increased significantly than those in 3-year-old, 6-year-old, 9-year-old stands, and the DOC, ROC and MBC contents increased by 113.1%, 53.3% and 54.6%, respectively, compared with those in the 21-year-old P. elliottii pure plantation. The results suggested that replanting with broadleaf trees are an effective measure to improve the soil ecological function in pure P. elliottii plantation.

  14. Age of oil palm plantations causes a strong change in surface biophysical variables

    Science.gov (United States)

    Sabajo, Clifton; le Maire, Guerric; Knohl, Alexander

    2016-04-01

    Over the last decades, Indonesia has experienced dramatic land transformations with an expansion of oil palm plantations at the expense of tropical forests. As vegetation is a modifier of the climate near the ground these large-scale land transformations are expected to have major impacts on the surface biophysical variables i.e. surface temperature, albedo, and vegetation indices, e.g. the NDVI. Remote sensing data are needed to assess such changes at regional scale. We used 2 Landsat images from Jambi Province in Sumatra/Indonesia covering a chronosequence of oil palm plantations to study the 20 - 25 years life cycle of oil palm plantations and its relation with biophysical variables. Our results show large differences between the surface temperature of young oil palm plantations and forest (up to 9.5 ± 1.5 °C) indicating that the surface temperature is raised substantially after the establishment of oil palm plantations following the removal of forests. During the oil palm plantation lifecycle the surface temperature differences gradually decreases and approaches zero around an oil palm plantation age of 10 years. Similarly, NDVI increases and the albedo decreases approaching typical values of forests. Our results show that in order to assess the full climate effects of oil palm expansion biophysical processes play an important role and the full life cycle of oil palm plantations need to be considered.

  15. Poplar plantation has the potential to alter the water balance in semiarid inner Mongolia

    Science.gov (United States)

    Burkhard Wilske; Long Wei; Shiping Chen; Tonggang Zha; Chenfeng Liu; Wenting Xu; Asko Noormets; Jianhui Haung; Yafen Wei; Jun Chen; Zhiqiang Zhang; Jian Ni; Ge Sun; Kirk Guo; Steve McNulty; Ranjeet John; Xiangguo Han; Guanghui Lin; Jiquan Chen

    2009-01-01

    Poplar plantation is the most dominant broadleaf forest type in northern China. Since the mid-1990s plantation was intensified to combat desertification along China’s northwestern border, i.e., within Inner Mongolia (IM). This evoked much concern regarding the ecological and environmental effects on areas that naturally grow grass or shrub vegetation. To highlight...

  16. Energy partitioning and surface resistance of a poplar plantation in northern China

    Science.gov (United States)

    M. Kang; Z. Zhang; A. Noormets; X. Fang; T. Zha; J. Zhou; G. Sun; S. G. McNulty; J. Chen

    2015-01-01

    Poplar (Populus sp.) plantations have been, on the one hand, broadly used in northern China for urban greening, combating desertification, as well as for paper and wood production. On the other hand, such plantations have been questioned occasionally for their possible negative impacts on water availability due to the higher water-use nature of...

  17. Soil seed banks in four 22-year-old plantations in South China: implications for restoration

    Science.gov (United States)

    Jun Wang; Hai Ren; Long Yang; Danyan Li; Qinfeng. Guo

    2009-01-01

    To better understand the potentials of the soil seed banks in facilitating succession towards a morenatural forest of native tree species, we quantified the size and composition of the soil seed banks inestablished plantations in South China. The seed banks were from four typical 22-year-old plantations, i.e., legume, mixed-...

  18. Long-term hydrology and water quality of a drained pine plantation in North Carolina

    Science.gov (United States)

    D.M. Amatya; R.W. Skaggs

    2011-01-01

    Long-term data provide a basis for understanding natural variability, reducing uncertainty in model inputs and parameter estimation, and developing new hypotheses. This article evaluates 21 years (1988-2008) of hydrologic data and 17 years (1988-2005) of water quality data from a drained pine plantation in eastern North Carolina. The plantation age was 14 years at the...

  19. Soil microbial communities and enzyme activities in sea-buckthorn (Hippophae rhamnoides plantation at different ages.

    Directory of Open Access Journals (Sweden)

    Miao Yang

    Full Text Available The aim of this study was to assess the impact of forest age and season on the soil microbial community and enzyme activities in sea-buckthorn plantation system and to determine the relative contributions to soil microbial properties. Soil sampling was carried out in the dry season (April and wet season (September in four areas, including: abandoned farmland (NH, an 8-year- old plantation (young plantation, 8Y, a 13-year-old plantation (middle-aged plantation, 13Y, and an 18-year-old plantation (mature plantation, 18Y. The results showed that forest age and season have a significant effect on soil microbial community structure and enzyme activities. The total, bacterial, fungal, Gram-negative (G+, and Gram-positive (G- PLFAs increased gradually with forest age, with the highest values detected in 18Y. All the detected enzyme activities showed the trend as a consequence of forest age. The microbial PLFAs and soil enzyme activities were higher in the wet season than the dry season. However, there were no significant interactions between forest age and season. A Correlation analysis suggested that soil microbial communities and enzyme activities were significantly and positively correlated with pH, total nitrogen (TN and available phosphorus (AP. Season had a stronger influence on soil microbial communities than forest age. In general, sea-buckthorn plantations establishment might be a potential tool for maintaining and increasing soil fertility in arid and semi-arid regions.

  20. Soil microbial communities and enzyme activities in sea-buckthorn (Hippophae rhamnoides) plantation at different ages.

    Science.gov (United States)

    Yang, Miao; Yang, Dan; Yu, Xuan

    2018-01-01

    The aim of this study was to assess the impact of forest age and season on the soil microbial community and enzyme activities in sea-buckthorn plantation system and to determine the relative contributions to soil microbial properties. Soil sampling was carried out in the dry season (April) and wet season (September) in four areas, including: abandoned farmland (NH), an 8-year- old plantation (young plantation, 8Y), a 13-year-old plantation (middle-aged plantation, 13Y), and an 18-year-old plantation (mature plantation, 18Y). The results showed that forest age and season have a significant effect on soil microbial community structure and enzyme activities. The total, bacterial, fungal, Gram-negative (G+), and Gram-positive (G-) PLFAs increased gradually with forest age, with the highest values detected in 18Y. All the detected enzyme activities showed the trend as a consequence of forest age. The microbial PLFAs and soil enzyme activities were higher in the wet season than the dry season. However, there were no significant interactions between forest age and season. A Correlation analysis suggested that soil microbial communities and enzyme activities were significantly and positively correlated with pH, total nitrogen (TN) and available phosphorus (AP). Season had a stronger influence on soil microbial communities than forest age. In general, sea-buckthorn plantations establishment might be a potential tool for maintaining and increasing soil fertility in arid and semi-arid regions.

  1. Le bois du frake issu de plantation exprime aussi de bonnes ...

    African Journals Online (AJOL)

    Mots-clés: Fraké de plantation, cubage, sciage, qualité physique et mécanique, Côte d'Ivoire. English Abstract. Objective: Technological qualities of the mature wood of Terminalia superba (Fraké) from plantation are badly known unlike those from wood from natural forest. Achieved work aimed to show the likeness between ...

  2. Site and stand factors affecting height growth curves of longleaf pine plantations

    Science.gov (United States)

    William D. Boyer

    1981-01-01

    Abstract Some factors related to the form of height-over- age curves in longleaf pine plantations were identified from analyses of 660 periodically remeasured plots.Seventy percent of the variation among 32 plantations in form the growth curve was accounted for by stratifying planting sites into old fields, mechanically prepared and unprepared cut-...

  3. Management of Eucalyptus plantations influence small mammals’ density: evidences from Southern Europe

    NARCIS (Netherlands)

    Teixeira, D; Carrilho, M; Mexia, T; Kobel, M; Ferreira Dos Santos, M.J.; Santos-Reis, Margarida; Rosalino, Luis Miguel

    2017-01-01

    Forestry plantations, and particularly those of exotic Eucalyptus, are important man-made systems in Europe, and especially in Portugal, where these represent now the largest fraction of forested areas. Eucalyptus plantations may have impacts on vertebrate communities in Europe; however, these have

  4. Determination of land and tree values of hybrid poplar plantations: a ...

    African Journals Online (AJOL)

    Valuation of poplar plantations is important in condemnation, taxation, loan, insurance, inheritance, and purchase-sale cases. In general, for the appraisal of land value of poplar plantations, sales comparison and income capitalization approaches can be used. In appraisal of tree values sales comparison, income ...

  5. An overview of industrial tree plantation conflicts in the global South: conflicts, trends, and resistance struggles

    NARCIS (Netherlands)

    W. Overbeek (Wilfridus); M. Kröger (Markus); J. Gerber (Julien-François)

    2012-01-01

    markdownabstractOver the past two decades, industrial tree plantations (ITPs), typically large-scale, intensively managed, even-age monoculture plantations, mostly exotic trees like fast-growing eucalyptus, pine and acacia species, but also rubber and oil palm, all destined for industrial processe s

  6. Short-rotation eucalypt plantations in Brazil: Social and environmental issues

    Energy Technology Data Exchange (ETDEWEB)

    Couto, L. [Universidade Federal de Vicosa, Minas Gerais (Brasil). Dept. de Engenharia Florestal; Betters, D.R. [Colorado State Univ., Fort Collins, CO (United States). Dept. of Forest Sciences

    1995-02-01

    This report presents an overview of the historical and current legislative, social, and environmental aspects of the establishment of large-scale eucalypt plantations in Brazil. The report consolidates the vast experience and knowledge relating to these forest plantation systems and highlights lessons learned and new trends. The overview should prove useful to those interested in comparing or beginning similar endeavors.

  7. Growth models for ponderosa pine: I. Yield of unthinned plantations in northern California.

    Science.gov (United States)

    William W. Oliver; Robert F. Powers

    1978-01-01

    Yields for high-survival, unthinned ponderosa pine (Pinus ponderosa Laws.) plantations in northern California are estimated. Stems of 367 trees in 12 plantations were analyzed to produce a growth model simulating stand yields. Diameter, basal area, and net cubic volume yields by Site Indices50 40 through 120 are tabulated for...

  8. Productivity and nitrogen use of tea plantations in relation to age and genotype

    NARCIS (Netherlands)

    Kamau, D.M.; Spiertz, J.H.J.; Oenema, O.; Owuor, P.O.

    2008-01-01

    Lack of science-based knowledge on responses of tea bushes to nitrogen (N) in ageing tea plantations hampers the development of ecologically sound and economically profitable N-management strategies. It is hypothesized that ageing of tea plantations lowers productivity and weakens the yield response

  9. Managing for water-use efficient wood production in Eucalyptus globulus plantations

    Science.gov (United States)

    Donald A. White; John F. McGrath; Michael G. Ryan; Michael Battaglia; Daniel S. Mendham; Joe Kinal; Geoffrey M. Downes; D. Stuart Crombie; Mark E. Hunt

    2014-01-01

    This paper tests the hypothesis that thinning and nitrogen fertiliser can increase the mass of wood produced per volume of water used (evapotranspiration) by plantations of Eucalyptus globulus. We have called this plantation water productivity (PWPWOOD) and argue that, for a given genotype, this term integrates the effects of management, site and climate on both...

  10. Perspectives on site productivity of loblolly pine plantations in the southern United States

    Science.gov (United States)

    Eric D. Vance; Felipe G. Sanchez

    2006-01-01

    Pine plantations in the U.S. South include some of the most intensively managed and productive forests in the world. Studies have been established in recent decades to answer questions about whether the productivity of these plantations is sustainable. While intensive management practices greatly enhance tree growth, their effects on factors controlling growth...

  11. Effects of irrigation on water use and water use efficiency in two fast growing Eucalyptus plantations

    Science.gov (United States)

    Robert M. Hubbard; Jose Stape; Michael G. Ryan; Auro C. Almeida; Juan Rojas

    2010-01-01

    Eucalyptus plantations occupy almost 20 million ha worldwide and exceed 3.7 million ha in Brazil alone. Improved genetics and silviculture have led to as much as a three-fold increase in productivity in Eucalyptus plantations in Brazil and the large land area occupied by these highly productive ecosystems raises concern over their...

  12. FROM UAS DATA ACQUISITION TO ACTIONABLE INFORMATION – HOW AN END-TO-END SOLUTION HELPS OIL PALM PLANTATION OPERATORS TO PERFORM A MORE SUSTAINABLE PLANTATION MANAGEMENT

    Directory of Open Access Journals (Sweden)

    C. Hoffmann

    2016-06-01

    The research results describe how operators can successfully make use of a UAS-based solution together with the developed software solution to improve their efficiency in oil palm plantation management.

  13. Soil macrofauna and litter nutrients in three tropical tree plantations on a disturbed site in Puerto Rico.

    Science.gov (United States)

    Matthew W. Warren; Xiaoming Zou

    2002-01-01

    Tree plantations are increasingly common in tropical landscapes due to their multiple uses. Plantations vary in structure and composition, and these variations may alter soil fauna communities. Recent studies have demonstrated the important role of soil fauna in the regulation of plant litter decomposition in the tropics. However, little is known about how plantation...

  14. Eco-exergy and emergy based self-organization of three forest plantations in lower subtropical China

    Science.gov (United States)

    The bio-thermodynamic structures of a mixed native species plantation, a conifer plantation and an Acacia mangium plantation in Southern China were quantified over a period of 15 years based on eco-exergy methods. The efficiencies of structural development and maintenance were qu...

  15. [Comparison of heavy metal elements between natural and plantation forests in a subtropical Montane forest].

    Science.gov (United States)

    Nie, Ming; Wan, Jia-Rong; Chen, Xiao-Feng; Wang, Li; Li, Bo; Chen, Jia-Kuan

    2011-11-01

    Heavy metals as one of major pollutants is harmful to the health of forest ecosystems. In the present paper, the concentrations of thirteen heavy metals (Fe, Al, Ti, Cr, Cu, Mn, V, Zn, Ni, Co, Pb, Se and Cd) were compared between natural and plantation forests in the Mt. Lushan by ICP-AES and atomic absorption spectroscopy. The results suggest that the soil of natural forest had higher concentrations of Fe, Al, Ti, Cu, Mn, V, Zn, Ni, Co, Pb, Se, and Cd than the plantation forest except for Cr. The soil of natural forest had a higher level of heavy metals than that of the plantation forest as a whole. This might be due to that the natural forest has longer age than the plantation forest, and fixed soil heavy metals take a longer period of time than the plantation forest.

  16. Inter-annual climate variability and zooplankton: applying teleconnection indices to two deep subalpine lakes in Italy

    Directory of Open Access Journals (Sweden)

    Marina Manca

    2014-08-01

    Full Text Available Investigating relation between meteo-climatic indices and between-year variation in Daphnia population density and phenology is crucial for e.g. predicting impact of climate change on lake ecosystem structure and functioning. We tested whether and how two teleconnection indices calculated for the winter period, namely the East Atlantic pattern (EADJF and the Eastern Mediterranean Pattern (EMPDJF were correlated with Daphnia population growth in two Italian subalpine lakes, Garda and Maggiore. We investigated between-lake temporal coherence in: i water temperature within the water layer in which Daphnia is distributed; ii timing of Daphnia initial and spring maximum population density peak and iii the level of Daphnia spring maximum population density peak over an eleven-year period (1998-2008 of unchanged predation pressure by fish and invertebrates, and of common oligotrophy. Between-lake temporal coherence was high for an earlier start, an earlier, and lower, Daphnia population spring density peak after milder winters. Peak density level was coherently, positively correlated with soluble reactive phosphorus (SRP concentration. We hypothesized that Daphnia peak densities were related to atmospheric modes of variability in winter and to the degree of late winter mixing promoting replenishment of algal nutrients into upper water layers and phytoplankton growth, enhancing food availability and Daphnia fecundity, promoting Daphnia peak. 

  17. Equine Grazing in Managed Subalpine Wetlands: Effects on Arthropods and Plant Structure as a Function of Habitat

    Science.gov (United States)

    Holmquist, Jeffrey G.; Schmidt-Gengenbach, Jutta; Haultain, Sylvia A.

    2013-12-01

    Grazing management necessarily emphasizes the most spatially extensive vegetation assemblages, but landscapes are mosaics, often with more mesic vegetation types embedded within a matrix of drier vegetation. Our primary objective was to contrast effects of equine grazing on both subalpine vegetation structure and associated arthropods in a drier reed grass ( Calamagrostis muiriana) dominated habitat versus a wetter, more productive sedge habitat ( Carex utriculata). A second objective was to compare reed grass and sedge as habitats for fauna, irrespective of grazing. All work was done in Sequoia National Park (CA, USA), where detailed, long-term records of stock management were available. We sampled paired grazed and control wet meadows that contained both habitats. There were moderate negative effects of grazing on vegetation, and effects were greater in sedge than in reed grass. Conversely, negative grazing effects on arthropods, albeit limited, were greater in the drier reed grass, possibly due to microhabitat differences. The differing effects on plants and animals as a function of habitat emphasize the importance of considering both flora and fauna, as well as multiple habitat types, when making management decisions. Sedge supported twice the overall arthropod abundance of reed grass as well as greater diversity; hemipteran and dipteran taxa were particularly abundant in sedge. Given the greater grazing effects on sedge vegetation, greater habitat provision for terrestrial arthropods, and value as aquatic arthropod habitat, the wetter sedge assemblage is worthy of additional consideration by managers when planning for grazing and other aspects of land usage.

  18. The effects of winter recreation on alpine and subalpine fauna: a systematic review and meta-analysis.

    Directory of Open Access Journals (Sweden)

    Chloe F Sato

    Full Text Available The ski industry is often perceived as having a negative impact on sensitive alpine and subalpine communities. However, empirical evidence of such impacts is lacking. We reviewed the available literature from the last 35 years to quantify the reported effects of winter recreation on faunal communities. Overall, using one-sample binomial tests ('sign tests' we found that the effects of all types of winter recreation-related disturbances (i.e. ski runs, resort infrastructure and winter tourism were more likely to be negative or have no effect, than be positive for wildlife. More specifically, in Europe, where the majority of the available research was conducted, the impacts of winter recreation were most often negative for fauna. In terms of specific taxa, birds and to a lesser extent mammals and arthropods, responded negatively to disturbance. Results from our meta-analysis confirmed the results from our binomial tests. Richness, abundance and diversity of fauna were lower in areas affected by winter recreation when compared with undisturbed areas. For most regions and taxa, however, empirical evidence remains too limited to identify clear impacts of winter recreation. We therefore conclude that the majority of ski resorts are operating in the absence of knowledge needed to inform effective strategies for biodiversity conservation and ecologically-sound management. Thus, there is an urgent need for more empirical research to be conducted throughout this increasingly threatened ecological community, especially given the indication from the available literature that fauna often respond negatively to winter recreation.

  19. Nutrient status in soil of Ski runs in the sub-alpine belt of Uludag Mountain, Bursa, Turkey.

    Science.gov (United States)

    Guleryuz, Gurcan; Kirmizi, Serap; Arslan, Hulya

    2010-01-01

    Large areas of land are disturbed in sensitive bio-diverse mountain environments by Skiruns. Restoration of vegetation on such disturbed mountain sites may be hampered by soil degradation but the severity and nature of the constraints is not well understood. This study was designed to compare the water holding and nutritional status of soil in three Ski runs which had different construction dates and disturbance levels, and the adjacent undisturbed site in the Abies bommuelleriana forest community in the sub-alpine belt of Uludag Mountain (Bithynian Olympus). The values of soil parameters were depressed in proportion to the disturbance level. Water holding capacity (WHC), total nitrogen (N), organic carbon (C) and calcium (Ca2+), magnesium (Mg2+) and potassium (K+) contents (mg kg(-1) dry weight) of soils in the Ski run which had the highest disturbance level were lower than that of the undisturbed adjacent sites. However the results indicated that the soil parameters were less degraded when secondary vegetation was growing on the disturbed areas.

  20. The Effects of Winter Recreation on Alpine and Subalpine Fauna: A Systematic Review and Meta-Analysis

    Science.gov (United States)

    Sato, Chloe F.; Wood, Jeff T.; Lindenmayer, David B.

    2013-01-01

    The ski industry is often perceived as having a negative impact on sensitive alpine and subalpine communities. However, empirical evidence of such impacts is lacking. We reviewed the available literature from the last 35 years to quantify the reported effects of winter recreation on faunal communities. Overall, using one-sample binomial tests (‘sign tests’) we found that the effects of all types of winter recreation-related disturbances (i.e. ski runs, resort infrastructure and winter tourism) were more likely to be negative or have no effect, than be positive for wildlife. More specifically, in Europe, where the majority of the available research was conducted, the impacts of winter recreation were most often negative for fauna. In terms of specific taxa, birds and to a lesser extent mammals and arthropods, responded negatively to disturbance. Results from our meta-analysis confirmed the results from our binomial tests. Richness, abundance and diversity of fauna were lower in areas affected by winter recreation when compared with undisturbed areas. For most regions and taxa, however, empirical evidence remains too limited to identify clear impacts of winter recreation. We therefore conclude that the majority of ski resorts are operating in the absence of knowledge needed to inform effective strategies for biodiversity conservation and ecologically-sound management. Thus, there is an urgent need for more empirical research to be conducted throughout this increasingly threatened ecological community, especially given the indication from the available literature that fauna often respond negatively to winter recreation. PMID:23691190

  1. Using time scales to characterize phytoplankton assemblages in a deep subalpine lake during the thermal stratification period: Lake Iseo, Italy

    Science.gov (United States)

    Marti, Clelia Luisa; Imberger, Jörg; Garibaldi, Letizia; Leoni, Barbara

    2016-03-01

    A combination of field observations and 3-D hydrodynamic simulations were used to identify the phytoplankton species and to estimate the various time scales of the dominant physical and biological processes in Lake Iseo, a deep subalpine lake located in northern Italy, during a stratified period (July 2010). By ordering the rate processes time scales, we derive a phytoplankton patch categorization and growth interpretation that provides a general framework for the spatial distribution of phytoplankton concentration in Lake Iseo and illuminates the characteristics of their ecological niches. The results show that the diurnal surface layer was well mixed, received strong diurnal radiation, had low phosphorus concentrations and the phytoplankton biomass was sustained by the green alga Sphaerocystis schroeterii. The vertical mixing time scales were much shorter than horizontal mixing time scales causing a depth-uniform chlorophyll a concentration. The horizontal patch scale was determined by horizontal dispersion balancing the phytoplankton growth time scale, dictating the success of the observed green algae. The strongly stratified nutrient-rich metalimnion had mild light conditions and Diatoma elongatum and Planktothrix rubescens made up the largest proportions of the total phytoplankton biomass at the intermediate and deeper metalimnetic layers. The vertical transport time scales were much shorter than horizontal transport and vertical dispersion leading to growth niche for the observed phytoplankton. The study showed that time-scale hierarchy mandates the essential phytoplankton attributes or traits for success in a particular section of the water column and/or water body.

  2. Using functional traits to assess the resistance of subalpine grassland to trampling by mountain biking and hiking.

    Science.gov (United States)

    Pickering, Catherine Marina; Barros, Agustina

    2015-12-01

    Functional traits reflect plant responses to disturbance, including from visitor impacts. The impacts of mountain biking and hiking on functional composition were compared using a common experimental protocol in a subalpine grassland in the Australian Alps. The overlapping cover of all species was recorded two weeks after different intensities of hiking (200 and 500 passes) and mountain biking (none, 25, 75, 200 and 500 passes). Species' functional trait data were combined with their relative cover to calculate community trait weighted means for plant height, leaf area, percentage leaf dry matter content and Specific Leaf Area (SLA). Species such as Poa fawcettiae with larger leaves and SLA but lower dry weight content of leaves were more resistant to use, with differences between bikers and hikers only apparent at the highest levels of use tested. This differs from some vegetation communities in Europe where plants with smaller leaves were more resistant to hiking. More research using functional traits may account for differences in species responses to trampling. Managers of conservation areas used for hiking and biking need to minimise off trail use by both user groups. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Virtual disjunct eddy covariance measurements of organic compound fluxes from a subalpine forest using proton transfer reaction mass spectrometry

    Directory of Open Access Journals (Sweden)

    T. G. Karl

    2002-01-01

    Full Text Available A `virtual' disjunct eddy covariance (vDEC device was tested with field measurements of biogenic VOC fluxes at a subalpine forest site in the Rocky Mountains of the USA. A PTR-MS instrument was used as the VOC sensor. Daily peak emission fluxes of 2-methyl-3-buten-2-ol (MBO, methanol, acetone and acetaldehyde were around 1.5, 1, 0.8 and 0.4 mg m-2 h-1, respectively. High pass filtering due to long sampling lines was investigated in laboratory experiments, and suggested that VOC losses in PTFA lines are generally governed by diffusion laws. Memory effects and surface reactions did not seem to play a dominant role. Model estimates of MBO fluxes compared well with measured fluxes. The results also suggest that latent heat and sensible heat fluxes are reasonably well correlated with VOC fluxes and could be used to predict variations in VOC emissions. The release of MBO, methanol, acetone and acetaldehyde resulted in significant change of tropospheric oxidant levels and a 10--40% increase in ozone levels, as inferred from a photochemical box model. We conclude that vDEC with a PTR-MS instrument is a versatile tool for simultaneous field analysis of multiple VOC fluxes.

  4. Complex terrain alters temperature and moisture limitations of forest soil respiration across a semiarid to subalpine gradient

    Science.gov (United States)

    Berryman, Erin Michele; Barnard, H.R.; Adams, H.R.; Burns, M.A.; Gallo, E.; Brooks, P.D.

    2015-01-01

    Forest soil respiration is a major carbon (C) flux that is characterized by significant variability in space and time. We quantified growing season soil respiration during both a drought year and a nondrought year across a complex landscape to identify how landscape and climate interact to control soil respiration. We asked the following questions: (1) How does soil respiration vary across the catchments due to terrain-induced variability in moisture availability and temperature? (2) Does the relative importance of moisture versus temperature limitation of respiration vary across space and time? And (3) what terrain elements are important for dictating the pattern of soil respiration and its controls? Moisture superseded temperature in explaining watershed respiration patterns, with wetter yet cooler areas higher up and on north facing slopes yielding greater soil respiration than lower and south facing areas. Wetter subalpine forests had reduced moisture limitation in favor of greater seasonal temperature limitation, and the reverse was true for low-elevation semiarid forests. Coincident climate poorly predicted soil respiration in the montane transition zone; however, antecedent precipitation from the prior 10 days provided additional explanatory power. A seasonal trend in respiration remained after accounting for microclimate effects, suggesting that local climate alone may not adequately predict seasonal variability in soil respiration in montane forests. Soil respiration climate controls were more strongly related to topography during the drought year highlighting the importance of landscape complexity in ecosystem response to drought.

  5. The effects of winter recreation on alpine and subalpine fauna: a systematic review and meta-analysis.

    Science.gov (United States)

    Sato, Chloe F; Wood, Jeff T; Lindenmayer, David B

    2013-01-01

    The ski industry is often perceived as having a negative impact on sensitive alpine and subalpine communities. However, empirical evidence of such impacts is lacking. We reviewed the available literature from the last 35 years to quantify the reported effects of winter recreation on faunal communities. Overall, using one-sample binomial tests ('sign tests') we found that the effects of all types of winter recreation-related disturbances (i.e. ski runs, resort infrastructure and winter tourism) were more likely to be negative or have no effect, than be positive for wildlife. More specifically, in Europe, where the majority of the available research was conducted, the impacts of winter recreation were most often negative for fauna. In terms of specific taxa, birds and to a lesser extent mammals and arthropods, responded negatively to disturbance. Results from our meta-analysis confirmed the results from our binomial tests. Richness, abundance and diversity of fauna were lower in areas affected by winter recreation when compared with undisturbed areas. For most regions and taxa, however, empirical evidence remains too limited to identify clear impacts of winter recreation. We therefore conclude that the majority of ski resorts are operating in the absence of knowledge needed to inform effective strategies for biodiversity conservation and ecologically-sound management. Thus, there is an urgent need for more empirical research to be conducted throughout this increasingly threatened ecological community, especially given the indication from the available literature that fauna often respond negatively to winter recreation.

  6. A Framework for Long-term Ecological Monitoring in Olympic National Park: Prototype for the Coniferous Forest Biome

    Science.gov (United States)

    Jenkins, Kurt; Woodward, Andrea; Schreiner, Ed

    2003-01-01

    This report is the result of a five-year collaboration between scientists of the U.S. Geological Survey Forest and Rangeland Ecosystem Science Center, Olympic Field Station, and the natural resources staff of Olympic National Park to develop a comprehensive strategy for monitoring natural resources of Olympic National Park. Olympic National Park is the National Park Serviceʼs prototype monitoring park, representing parks in the coniferous forest biome. Under the umbrella of the National Park Serviceʼs prototype parks program, U.S. Geological Survey and Olympic National Park staffs are obligated to:develop strategies and designs for monitoring the long-term health and integrity of national park ecosystems with a significant coniferous forest component.design exportable monitoring protocols that can be used by other parks within the coniferous forest biome (i.e., parks having similar environments), andcreate a demonstration area and ʻcenter of excellenceʼ for assisting other parks in developing ecological monitoring programs.Olympic National Park is part of the North Coast and Cascades Network, a network of seven Pacific Northwestern park units created recently by the National Park Serviceʼs Inventory and Monitoring Program to extend the monitoring of ʻvital signsʼ of park health to all National Park Service units. It is our intent and hope that the monitoring strategies and conceptual models described here will meet the overall purpose of the prototype parks monitoring program in proving useful not only to Olympic National Park, but also to parks within the North Coast and Cascades Network and elsewhere. Part I contains the conceptual design and sampling framework for the prototype long-term monitoring program in Olympic National Park. In this section, we explore key elements of monitoring design that help to ensure the spatial, ecological, and temporal integration of monitoring program elements and discuss approaches used to design an ecosystem

  7. Identification of stand age in rubber plantations using time series Landsat and PALSAR-2 data

    Science.gov (United States)

    Chen, B.; Wu, Z.; Xiao, X.; Li, X.; Ma, J.; Lan, G.; Yang, C.; Xie, G.; Dong, J.; Qin, Y.

    2016-12-01

    Stand age of rubber plantation is vital for optimal plantation management such as fertilization, prediction of latex yield and timber production. It is also an important variable for biomass estimation and determining the distribution of carbon pools and fluxes in rubber plantation ecosystem. Benefit from the traits of large coverage, high speed, and low-cost, satellite remote sensing techniques have been serviced as a major approach to map acreage and stand age of forest and plantations. Despite a number of studies working on acreage and stand age mapping, the stand age information of rubber plantation is still poorly available at regional scale. In this study, the 25-m cloud-free Phased Array type L-band Synthetic Aperture Radar 2 (PALSAR-2) mosaic product, together with the 30-m time series images of Landsat 7 Enhanced Thematic Mapper Plus (ETM+) and Landsat 8 Operational Land Imager (OLI), were used to map stand age of rubber plantation in China under Google Earth Engine computing platform. Rubber plantation in 2015 were first identified by structural information in PALSAR-2 and phenological and spectral signatures (deciduous, rapid change of canopies during rubber defoliation and foliation periods, and dense canopy in growing season) that derived from time series Landsat ETM+/OLI images. Based on the resultant rubber plantation map, we then successfully identified the stand age of rubber plantation using land cover transfer information during rubber seeding cultivation period, specifically, by yearly composited Land Surface Water Index (LSWI) of Landsat TM/ETM+/OLI images since 1985. The estimated stand age has very high accuracy with Root Square Mean Error (RMSE) less than 2 years. The resultant rubber stand age information are likely to be useful for sustainable plantation management and ecological assessment, and the methodology can be extendable for applications in other regions.

  8. Genetic diversity in Populus nigra plantations from west of Iran

    Directory of Open Access Journals (Sweden)

    Afrooz Alimohamadi

    2012-11-01

    Full Text Available In order to adopt strategies for forest conservation and development,it is necessary to estimate the amount and distribution of genetic diversity in existing populations of poplar in Iran. In this study, the genetic diversity between eight stands of Populus nigra established in Kermanshah province was evaluated on the basis of molecular and morphological markers. To amplify microsatellite loci (WPMS09, WPMS16 and WPMS18, DNA extraction from young and fresh leaveswas done. Various conditions of the PCR assay were examined and to evaluate the morphological variation of the morphological characters leaves (consist of 19 traits were measured. In addition, height growth was measured, to evaluate the growth function of the stands in homogeneous conditions. Genetic diversity in termof polymorphic loci was 0%, because three investigated microsatellite loci were monomorphic. The total number of alleles for 3 microsatellite loci was 6 (na = 2, ne = 2, heo = 1, hee = 0.51. Genetic identity based on Nei was 100%, so genetic distance was 0%. The whole sampled trees represented the same thus the genotype. No significant differences between the mean values of all morphological characters and height growth were revealed. Observed genetic similarity gave indication that same ramets had been selected to plant in poplar plantation established in Kermanshah province.These results suggest the need for an initial evaluation of the genetic diversity in selected ramets for planting in plantation to avoid repetition.

  9. Genetic diversity in Populus nigra plantations from west of Iran

    Directory of Open Access Journals (Sweden)

    Afrooz Alimohamadi

    2012-12-01

    Full Text Available In order to adopt strategies for forest conservation and development, it is necessary to estimate the amount and distribution of genetic diversity in existing populations of poplar in Iran. In this study, the genetic diversity between eight stands of Populus nigra established in Kermanshah province was evaluated on the basis of molecular and morphological markers. To amplify microsatellite loci (WPMS09, WPMS16 and WPMS18, DNA extraction from young and fresh leaveswas done. Various conditions of the PCR assay were examined and to evaluate the morphological variation of the morphological characters leaves (consist of 19 traits were measured. In addition, height growth was measured, to evaluate the growth function of the stands in homogeneous conditions. Genetic diversity in term of polymorphic loci was 0%, because three investigated microsatellite loci were monomorphic. The total number of alleles for 3 microsatellite loci was 6 (na = 2, ne = 2, heo = 1, hee = 0.51. Genetic identity based on Nei was 100%, so genetic distance was 0%. The whole sampled trees represented the same thus the genotype. No significant differences between the mean values of all morphological characters and height growth were revealed. Observed genetic similarity gave indication that same ramets had been selected to plant in poplar plantation established in Kermanshah province. These results suggest the need for an initial evaluation of the genetic diversity in selected ramets for planting in plantation to avoid repetition.  

  10. Nutrient cycling in a RRIM 600 clone rubber plantation

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    Murbach Marcos Roberto

    2003-01-01

    Full Text Available Few reports have been presented on nutrient cycling in rubber tree plantations (Hevea brasiliensis Muell. Arg.. This experiment was carried out to evaluate: the effect of K rates on the amount of nutrients transfered to the soil in a 13-year old Hevea brasilensis RRIM 600 clone plantation, nutrient retranslocation from the leaves before falling to the soil, and nutrient loss by dry rubber export. The experiment started in 1998 and potassium was applied at the rates of 0, 40, 80 and 160 kg ha-1 of K2O under the crowns of 40 rubber trees of each plot. Literfall collectors, five per plot, were randomly distributed within the plots under the trees. The accumulated literfall was collected monthly during one year. The coagulated rubber latex from each plot was weighed, and samples were analyzed for nutrient content. Increasing K fertilization rates also increased the K content in leaf literfall. Calcium and N were the most recycled leaf nutrients to the soil via litterfall. Potassium, followed by P were the nutrients with the highest retranslocation rates. Potassium was the most exported nutrient by the harvested rubber, and this amount was higher than that transfered to the soil by the leaf literfall.

  11. Water Absorbing Plantation Clay for Vertical Greenery System

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    Yu Lih-Jiun

    2016-01-01

    Full Text Available With the arises of environmental conscious, the usage of vertical garden system has become more popular in urban cities. Citizens can enjoys the benefits of energy and cost saving besides ornamental effect. More investigations have been conducted on green facades led to the cities ecological enhancement.However, limited plants species can be planted for green facades systems as this system does not provide sufficient soil and nutrients for common plants. Alternative plantation methods such as planted box and felt system required additional maintenance attention. The idea of using clay composite which consists of nutritious soil, water absorbing polymer and flexible cement clay potentially become alternative vertical greenery systems that offers economic and sustainable plantation platform for more variety of plants.The fabricating of clay composite involved three processes, they are: mixing, moulding and drying. Physical properties characterisation (density, pH, compression test, aging test and water immersion test were tested on the dried fabricated clay composite to ensure their sustainability in tropical climate. The results showed that clay composite with 1.5 wt% of cement and 0.3 wt% superabsorbent polymer shows optimum water absorbing properties. This system are expected to enable more agriculture activities in urban living.

  12. Working With Plantation Communities: A Reflection of Social Issues

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    Abdul Rahman Saili

    2013-04-01

    Full Text Available Abstract The plantation industry in Malaysia is aggressively expanding over the past decade driven by global demands for palm oil as a food staple and more recently bio fuels. The rapid growth in the industry is heavily dependent upon high labour and workforce. Such intensity has carried out social impact on the communities including plantation workers, small holders and their dependents. Therefore, this paper will outline what appear to be never ending issues impetus social problems. Ethnic conflict, fighting, gambling, alcohol abuses are only a few issues that call for immediate multi-action plan from all involved stakeholders. Those issues can be the causes as well as the effects. The contributing factors form a chain reaction to the whole social dynamics in the plantation’s climate.The main aim is hence to breach the gap between industries, practitioners, and academicians in order to develop the competencies of the next generation social workers. They can play their roles in tackling the social issues, taking into account the different contexts and environment.

  13. Estimation of coniferous forest aboveground biomass with aggregated airborne small-footprint LiDAR full-waveforms.

    Science.gov (United States)

    Qin, Haiming; Wang, Cheng; Xi, Xiaohuan; Tian, Jianlin; Zhou, Guoqing

    2017-08-07

    Forest aboveground biomass (AGB) is critical for assessing forest productivity and evaluating carbon sequestration rates. Discrete-return LiDAR has been widely used to estimate forest AGB, however, fewer studies have estimated the coniferous forest AGB using airborne small-footprint full-waveform LiDAR data. The objective of this study was to extract a suite of newly proposed metrics from airborne small-footprint full-waveform LiDAR data and to evaluate the ability of these metrics in estimating coniferous forest AGB. To achieve this goal, each waveform was first preprocessed, including de-noising, smoothing, and normalization. Next, all the waveforms within each plot were aggregated into a large pseudo waveform and the return energy profile was generated. Then, the foliage profile was retrieved from the return energy profile based on the Geometric Optical and Radiative Transfer (GORT) model. Finally, a series of new return energy profile metrics and foliage profile metrics were extracted to estimate forest AGB. Simple linear regression was conducted to assess the correlation between each LiDAR metric and forest AGB. Stepwise multiple regression analysis was then carried out to select important prediction metrics and establish the optimal forest AGB estimation model. Results indicated that both return energy profile and foliage profile based height-related metrics were strongly correlated to forest AGB. The energy weighted canopy height (HEweight) (R = 0.88) and foliage area weighted height (HFweight) (R = 0.89) all had the highest correlation coefficients with forest AGB in return energy profile metrics and foliage profile metrics respectively. Energy height percentiles and foliage height percentiles also had the ability to explain AGB variation. The energy-related metrics, foliage area-related metrics, and bounding volume-related metrics derived from the return energy profile and foliage profile were not all sensitive to forest AGB. This study also concluded that

  14. THE BIOTECHNOLOGY OF EMBRYOGENIC CELL LINES OBTAINING AND PLANTLETS OF CONIFEROUS SPECIES IN SIBERIA IN CULTURE IN VITRO

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    Tretiakova I.

    2012-08-01

    Full Text Available Experiments of culturing the immature isolated embryos and megagamethophytes of Siberian coniferous species were carried out on different modified media: ½ LV medium for Pinus sibirica and Pinus pumila, MSG and AI media (patent № 2431651 for Larix sibirica and Larix gmelinii, DCR medium for Picea ajanensis. For induction of embryogenic callus every species needs the optimized medium supplemented with L-glutamine, casein hydrolysate, ascorbic acid and hormones with different concentrations and their different proportions. The active proliferation of embryonal masses is observed on the same medium with reduced concentration of cytokinins. The proliferation of embryonal masses was significantly improved when they were subcultured after dispersing in liquid medium. The somatic embryos from embryonal masses are matured on basal medium with ABA (60-120 mM and PEG. In spite of species specificity the embryogenesis of morphogenic structures had the same scheme: elongation and asymmetric division of somatic cells, formation of initial cells and embryonal tubes, development of globular, torpedo and bipolar somatic embryos, embryos maturation and germination. However, not all donor-plants of coniferous species can form the embryogenic cell lines and somatic embryos. The active development of embryonal masses and formation of somatic embryos are observed from zygotic embryo of hybrid seeds of P. sibirica and L. sibirica. The obtained embryogenic lines were characterized by different proliferative activity. During 10 months cultivation the value of embryonal masses in different lines was 140-570 g. The number of somatic embryos varies from 210 to 410 per 100 mg of callus fresh weight. Decreasing proliferation activity did not observed during 24-45 months cultivation. However, development of somatic embryos in long cultivated lines decreased. Maturation of somatic embryos and development of plantlets were established in L. sibirica and P. pumila 50

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2012-03-30

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

  16. Dispersion of Short- and Medium-Chain Chlorinated Paraffins (CPs) from a CP Production Plant to the Surrounding Surface Soils and Coniferous Leaves.

    Science.gov (United States)

    Xu, Jiazhi; Gao, Yuan; Zhang, Haijun; Zhan, Faqiang; Chen, Jiping

    2016-12-06

    Chlorinated paraffin (CP) production is one important emission source for short- and medium-chain CPs (SCCPs and MCCPs) in the environment. In this study, 48 CP congener groups were measured in the surface soils and coniferous leaves collected from the inner and surrounding environment of a CP production plant that has been in operation for more than 30 years to investigate the dispersion and deposition behavior of SCCPs and MCCPs. The average concentrations of the sum of SCCPs and MCCPs in the in-plant coniferous leaves and surface soils were 4548.7 ng g -1 dry weight (dw) and 3481.8 ng g -1 dw, which were 2-fold and 10-fold higher than those in the surrounding environment, respectively. The Gaussian air pollution model explained the spatial distribution of CPs in the coniferous leaves, whereas the dispersion of CPs to the surrounding surface soils fits the Boltzmann equation well. Significant fractionation effect was observed for the atmospheric dispersion of CPs from the production plant. CP congener groups with higher octanol-air partitioning coefficients (K OA ) were more predominant in the in-plant environment, whereas the ones with lower K OA values had the elevated proportion in the surrounding environment. A radius of approximately 4 km from the CP production plant was influenced by the atmospheric dispersion and deposition of CPs.

  17. Effects of Large Scale Poplar Plantations on the Hydrology of Semiarid Areas in Inner Mongolia

    Science.gov (United States)

    Wilske, B.; Lu, N.; Chen, S.; Liu, C.; Xu, W.; Noormets, A.; Wei, L.; Lin, G.; Miao, H.; Wei, Y.; Zhang, Z.; Chen, J.; Zha, T.; Ni, J.; Sun, G.; Guo, K.; McNulty, S.; John, R.; Chen, J.

    2007-12-01

    Tree plantation is widely practiced to counteract desertification. It often involves planting forests in semiarid and arid areas, which are naturally dominated by grass- or shrub steppe. Severe land degradation has been observed in the vast grasslands of Inner Mongolia, China. Under drying climates vegetation may naturally change from grass- to open shrub land. Current programs aim at a large number of poplar plantations to compose a super-scale shelterbelt to curb soil erosion, dust storms, and further loss of vegetation cover. However, the water consumption of poplar plantations can be expected to exceed the water use of grass- or shrub steppe. Hence, large-scale poplar plantation may significantly alter the water budget in the semiarid region. We compared Eddy- Covariance-derived evapotranspiration (ET) of a young poplar plantation and an adjacent shrub land south of the Yellow River in Inner Mongolia. In addition, ET from the semiarid site was compared with ET from an older poplar plantation growing under semi-humid conditions south of Beijing. In spite of 33% lower precipitation, ET was 6% higher from the young poplar plantation (236.52 mm) than from the natural shrub land (223.02 mm) based on the five-month period May- September 2006. The difference was mainly because of higher ET from the poplar plantation during the drier periods of the growing season. Further comparison with the older plantation outlined future potential of the poplars to exceed ET of the shrub land by 100-200%. To highlight potential hydrological consequences of large scale poplar plantations, ET values were set in relation to the total size of plantations projected for the area and the stream flow of the nearby Yellow River. Additional groundwater discharge by mature poplar plantations may equal 6.5-15% of the Yellow River mean stream flow. Thus, the water expenditure of poplar plantations renders them a questionable tool in sustainable arid-land management, particularly as climate

  18. Butterfly Diversity in Various Land Cover Types of PTPN V Tamora Oil Palm Plantation, Kampar, Riau

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    YANTO SANTOSA

    2017-03-01

    Full Text Available Abstrak. Santosa Y, Yohanna, Wahyuni I. 2017. Butterfly Diversity in Various Land Cover Types of PTPN V Tamora Oil Palm Plantation, Kampar, Riau. Pros Sem Nas Masy Biodiv Indon 7: 110-116. Indonesia’s palm oil production has increased to 32 million tons and a total of 27 million ton in exports, which is in line with the increasing number of plantations. Changes of forests into oil palm plantations have caused alterations on the ecosystems due to the monoculture nature of the plantings system. This has raised some concerns among the world’s community for the conservation of biodiversity, including butterflies. Ecologically, butterflies contributed in maintaining ecosystem balance and played important role in helping the pollinations of flowering plants. Therefore, it is necessary to conduct a research on the diversity of butterfly in various land cover types. The study was conducted in PTPN V Tamora, of Riau Province in 6 types of land covers (old-growth oil palm plantation aged 25 years, young-growth oil plam plantation aged 2 years, HCV (High Conservation Value area within the oil palm plantation, smallholding oil palm plantation (KSR, and secondary forests closest to the plantation. HCV area represented the primary forest and secondary forest represented the land cover prior to the establishment of the plantation. The study was conducted in March-April 2016. Data were collected using time search method for 3 hours (08: 00 to 11: 00 WIB and were analyzed using Margalef Index, Evenness Index, and Sorensen Similarity Index. Based on the observations, the total number of butterfly species found in the 6 land cover types were 39 species of 182 individuals, belonging to four families: Papilionidae (4 species, Nymphalidae (26 species, Pieridae (5 species, and Lycanidae (4 species. Nymphalidae had the most number of species, and the most species type found was Leptosia nina. The most numbers of species and individuals were found in the old

  19. For the Aphid fauna in the territory of Yenisei river basin. Communication 1. Aphids on coniferous plants

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    A. V. Gurov

    2016-02-01

    Full Text Available The paper reports on new and previously not well-known data on insufficiently studied fauna of aphids living on coniferous trees in Central Siberia of the basin of Yenisei river. This region is the extensive transect of latitudinal geographic zones from semi-desert in the South to the arctic deserts in the North. That is why this region is very peculiar. This is the reason for insufficient study of regional entomological fauna. Aphids (Homoptera: Aphidoideaare a very taxonomically and ecologically heterogeneous group of insects. The aphids living on conifer trees are notstudied completely on the territory of Yenisei basin. Due to this, the studying of not well-known and economicallyimportant aphids is actual. For example, the insufficient study of regional aphids is confirmed by the fact, that duringthree weeks only of the work for INTAS-94-0930 Project two new aphid species were found and described on thisterritory. Also, the new species of family Mindaridae, which was described in Mongolia in 1980, was found in Siberiafor the first time. These finds indicate the real possibility to describe an interesting conifer aphid complex in the absolutely unstudied forested territory between Angara and Lower Tunguska rivers. Geographical location, dates ofcollection and feeding preferences of different species are described. A general review of Yenisei basin Siberian aphidfauna is suggested for the first time ever.

  20. Photosynthesis, growth and competitive ability of some coniferous forest mosses and the influence of herbicides and heavy metals (Cu, Zn)

    Energy Technology Data Exchange (ETDEWEB)

    Stjernquist, I.

    1981-12-01

    The importance of morphological characteristics and environmental variables as controlling factors for photo- synthesis and growth of Dicranum polysetum, Pleurozium schreberi and Ptilium crista-castrensis were studied. The three mosses had maximum assimilation capacity in different segments of the shoot and the growth form determined to what degree the capacity could be utilized. CO/sub 2/ fixation was limited by nutrient supply and selectivity affected by the environmental variables. In situ growth in a certain habitat or during a certain season closely corresponded to the oscillation of the variables important for CO/sub 2/ fixation. Application of 2,4-D,MCPA,Triclopyr and Glyphosate to populations of Dicranum, Pleurozium and five co-existing species gave selective effects on assimilation and respiration depending on bryophyte and herbicide. Generally, Glyphosate had negative long-term effects on photosynthesis of coniferous mosses with the exception of Sphagnum squarrosum. MCPA, 2,4-D and Triclopyr immediately decreased CO/sub 2/ fixation to maximally 30% of the control (Pleurozium and Hylocomium splendens). After one month CO/sub 2/ assimilation increased. Effects of varying concentrations of 2,4-D, and Glyphosate were studied and the influence on growth discussed. Assimilation and respiration of Dicranum was negatively related to increasing content of Cu+Zn in the shoot. The effect was significant at concentrations twice the background level.

  1. Mercury in forest mushrooms and topsoil from the Yunnan highlands and the subalpine region of the Minya Konka summit in the Eastern Tibetan Plateau.

    Science.gov (United States)

    Falandysz, Jerzy; Saba, Martyna; Liu, Hong-Gao; Li, Tao; Wang, Ji-Peng; Wiejak, Anna; Zhang, Ji; Wang, Yuan-Zhong; Zhang, Dan

    2016-12-01

    This study aimed to investigate and discuss the occurrence and accumulation of mercury in the fruiting bodies of wild-growing fungi (Macromycetes) collected from montane forests in two regions of southwestern China with differences in soil geochemistry, climate and geographical conditions. Fungal mycelia in soils of the subalpine region of the Minya Konka (Gongga Mountain) in Sichuan and in the highlands of Yunnan efficiently accumulated mercury in fruiting bodies (mushrooms). The examined sites in Yunnan with highly mineralized red and yellow soils showed Hg contents ranging from 0.066 to 0.28 mg kg -1 dry biomass (db) which is roughly similar to the results obtained for samples collected from sites with dark soils relatively rich in organic matter from a remote, the subalpine region of Minya Konka. Due to the remoteness of the subalpine section of Minya Konka, as well as its elevation and climate, airborne mercury from long-range transport could be deposited preferentially on the topsoil and the Hg levels determined in soil samples taken beneath the fruiting bodies were up to 0.48 mg kg -1 dry matter. In Yunnan, with polymetallic soils (Circum-Pacific Mercuriferous Belt), Amanita mushrooms showed mercury in caps of fruiting bodies of up to 7.3 mg kg -1 dry biomass. Geogenic Hg from the mercuriferous belt seems to be the overriding source of mercury accumulated in mushrooms foraged in the regions of Yunnan, while long-range atmospheric transport and subsequent deposition are the mercury sources for specimens foraged in the region of Minya Konka.

  2. Diphyllobothrium latum (Cestoda: Diphyllobothriidea in perch (Perca fluviatilis in three sub-alpine lakes: influence of biotic and abiotic factors on prevalence

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    Orlando PETRINI

    2009-08-01

    Full Text Available In recent years, human diphyllobothriosis has staged a comeback in Swiss, French and Italian sub-alpine regions. The main putative infective source of the causative agent (the tapeworm Diphyllobothrium latum in these areas is perch (Perca fluviatilis. Therefore, the occurrence of D. latum in this fish species was investigated between 2005 and 2008 in the sub-alpine lakes Maggiore, Lugano and Geneva. Prevalence in fish of Lake Maggiore was 14% (n = 880. In Lake Geneva, 5.1% fillets (n = 532 were infected, whereas perch from Lake Lugano were free from the parasite. These results are discussed in relation to previous studies. Data on fish size and weight indicate that infection of perch by D. latum is independent of age and sex. Abiotic factors considered critical for D. latum life cycle (water temperature and oxygen concentration characterize the three basins and were related to their infestation frequencies. The presence of this parasite was most likely favoured by warmer, well oxygenated waters. Previous studies indicate that the lake’s trophic state (i.e. content of total phosphorus influenced the availability of the first intermediate hosts (copepods of some pseudophyllideans. In our study, no correlation was observed between the amount of phosphorus and the number of copepods in populations of zooplankton. Nevertheless, the trophic states of the three lakes seemed to affect the degree of infection in fish. In conclusion, at least in sub-alpine lakes, abiotic factors such as water temperature, oxygenation and trophic state seem to have an influence on maintaining or preventing perch infection with D. latum.

  3. The weed species composition in a reed canary grass (Phalaris arundinacea L. plantation for energy purposes depending on its age

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    Tomasz R. Sekutowski

    2014-12-01

    Full Text Available The present experiment, carried out in nine production fields of reed canary grass (Phalaris arundinacea grown for energy purposes, evaluated the effect of plantation age on the occurrence and species composition of weeds. The selected plantations were divided into 3 groups that were conventionally called “young” (1–2 years old, “middle-aged” (3–5 years old, and “older” plantations (6–8 years old. Regardless of plantation age, altogether 43 species were found in the experimental fields. Moreover, 6 species were common for all the plantations and were found in them regardless of plantation age. The least species, only 18, were found on the “young” plantations, almost twice more on the “older” ones (30 species, whereas the largest spectrum of species was found in the “middle-aged” plantations (33 species. In the “young” plantations, annual weeds were the most common, with the highest constancy and coverage index found for Chenopodium album, Matricaria maritima ssp. inodora and Echinochloa crus-galli. The greatest variation in species was found in the “middle-aged” plantations. However, only 4 species achieved the highest constancy and coverage index: Matricaria maritima ssp. inodora, Cirsium arvense, Poa trivialis and Taraxacum officinale. Furthermore, perennial weeds were found to be dominant in the “older” plantations. Within this group, Poa trivialis, Taraxacum officinale, Urtica dioica, Plantago maior, and Cirsium arvense had the highest constancy and coverage index.

  4. An interdisciplinary framework to evaluate bioshield plantations: Insights from peninsular India

    Science.gov (United States)

    Mukherjee, Nibedita; Dahdouh-Guebas, Farid; Koedam, Nico; Shanker, Kartik

    2015-02-01

    Bioshields or coastal vegetation structures are currently amongst the most important coastal habitat modification activities in south-east Asia, particularly after the December 2004 tsunami. Coastal plantations have been promoted at a large scale as protection against severe natural disasters despite considerable debate over their efficacy as protection measures. In this paper, we provide an interdisciplinary framework for evaluating and monitoring coastal plantations. We then use this framework in a case study in peninsular India. We conducted a socio-ecological questionnaire-based survey on government and non-government organizations directly involved in coastal plantation efforts in three 2004 Indian Ocean tsunami affected states in mainland India. We found that though coastal protection was stated to be the primary cause, socio-economic factors like providing rural employment were strong drivers of plantation activities. Local communities were engaged primarily as daily wage labour for plantation rather than in the planning or monitoring phases. Application of ecological criteria has been undermined during the establishment and maintenance of plantations and there was a general lack of awareness about conservation laws relating to coastal forests. While ample flow of international aid has fuelled the plantation of exotics in the study area particularly after the Indian Ocean tsunami in 2004, the long term ecological consequences need further evaluation and rigorous monitoring in the future.

  5. Predicting effects of plantation expansion on streamflow regime for catchments in Australia

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    L. Zhang

    2012-07-01

    Full Text Available The effect of plantations on mean annual streamflow is well understood and, there are robust methods available for assessing the impact. Plantations also affect streamflow regime, leading to reductions in low flow and increased number of zero-flow days. Understanding changes in streamflow regime following plantation expansion is important for developing water resources and environmental flow strategy. This study evaluated the impacts of plantations on streamflow regime from 15 catchments in Australia. The selected catchments range in size from 0.6 to 1136 km2 and represent different climatic conditions and management practices. The catchments have at least 20 yr and in most cases 35 yr of continuous daily streamflow data and well documented plantation records. Catchments with perennial streamflow in the pre-treatment periods showed relatively uniform reductions in most flows after plantation expansions, whereas catchments with ephemeral streamflow showed more dramatic reductions in low flows, leading to an increased number of zero-flow days. The Forest Cover Flow Change (FCFC model was tested using the data from the selected catchments and comparison of predicted and observed flow duration curves showed that 14 of the 15 catchments have coefficients of efficiency greater than 0.8. The results indicate that the model is capable of predicting plantation impacts on streamflow regime.

  6. Community perceptions towards the establishment of an urban forest plantation: a case of Dzivaresekwa, Zimbabwe

    Directory of Open Access Journals (Sweden)

    A. Mureva

    2014-06-01

    Full Text Available The health of urban forest communities not only depend on the government and nongovernmental organizations, but also strongly rely on local community stewardship. A study was carried out to assess community perceptions on the establishment of an urban forest plantation among urban residents in Dzivaresekwa, an urban area in Harare. Randomized systematic sampling was used to select 150 households and one resident per household was interviewed using a pretested questionnaire with both closed and open-ended questions. The objectives of the study were to determine how age and gender and employment status variables, were related to the urban residents’ perceptions towards establishment of a forest plantation in an urban area. Most females (58.3% viewed the plantation as a threat while most men (51.7% viewed the plantation as a recreational area. The highest proportion (61.9% of the middle age group (21-40 years perceived the plantation as a source of employment. There was a statistically significant relationship (p = 0.040 between gender and the general perception of establishing a forest plantation in the urban area. However, there was no statistically significant relationship (p = 0.203 between age groups and the perception of establishing a forest plantation in the urban area. It is concluded that the community had diverse perceptions on urban community forestry.

  7. Simulating Harvest Schedule for Timber Management and Multipurpose Management in Teak Plantations

    Directory of Open Access Journals (Sweden)

    Tatang Tiryana

    2016-04-01

    Full Text Available Sustainable management of teak plantations in Java requires an improvement of the existing yield regulation method to optimize multiple benefits of the plantations at risk of stand destruction. This study was therefore aimed to formulate an alternative harvest scheduling model that integrates risk of stand destruction for supporting multipurpose management of teak plantations. The proposed model used a state-space planning model to simulate the dynamic of plantations due to timber harvesting and stand destruction, and then sought optimal solutions for 2 management scenarios, i.e. timber management that optimized total harvest volume and multipurpose management that optimized net present value (NPV while increasing carbon stocks. Using a case study on a typical teak plantation, this study confirmed that increasing destruction rates reduced harvest volumes, NPV, carbon stocks, and resulted in imbalanced ending age-class structures. Reducing cutting-age limit increased harvest volumes and NPV, but it also reduced carbon stocks of the plantations. Although the multipurpose management generated lower financial benefit, it maintained carbon stocks and produced better ending age-class structures compared to timber management. The proposed harvest scheduling model provides a useful planning tool for managing teak plantations.

  8. ACCOUNTING PARADIGM OF LIVED EXPERIENCES IN ACTION RESEARCH: THE CASE OF MALAYSIAN PLANTATION WORKERS

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    S. Susela DEVI

    2014-11-01

    Full Text Available This paper introduces action research as a possible new method to reduce the distance between idealism and accounting practice, thus contributing to the accounting literature. The source of this paper is an on-going large research project. The project has three objectives. Firstly, to provide evidence of the utilisation of accounting methods in the Malaya plantation industry from its earliest beginnings through to the introduction of accounting tools such as budgets, leading to the creation of a social and economic underclass in Malaysia. Secondly, to examine the extent to which accounting information provided in the Annual Reports of Malaysian plantation companies is used in determining the wages of plantation workers on the grounds that workers in the plantation industry have been and still are, among the most poorly paid in Malaysia, and perhaps the world. Interestingly, the wages of plantation workers are determined through a negotiation process between the National Union of Plantation Workers and the Malaysian Agricultural Producers Association. This paper draws from this research project and explicates the utilisation of the Action Research methodology in reporting the “lived experiences” of those affected by Management Accounting budgets and demonstrating how the parties to wage negotiation, the employers, union and employees, can better derive value from accounting information provided within the annual reports of Malaysian plantation companies.

  9. Sustainable Management of Metasequoia glyptostroboides Plantation Forests in Shanghai

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    Ji Zheng

    2018-01-01

    Full Text Available Urban forestry is increasingly used as a tool for climate change mitigation and for providing environmental services to inhabitants of urban areas. However, tree species used in urban forestry are usually different from the ones used in commercial forestry. As a consequence, available data on growth and yield under alternative management scenarios are usually scarce. As forest models can be used to explore potential forest futures, they are of special interest as decision-support tools in urban forestry. In this research, we used the FORECAST ecosystem-level forest model to define the management prescriptions for Metasequoia glyptostroboides plantations in Shanghai that reach the highest net primary productivity (NPP. In a first step, a battery of different stand densities (from 500 to 4000 stems ha−1 was used to identify those with the highest NPP at stand level. Then, different thinning regimes (with intensities ranging from 15% to 40% of trees removed and applied at stand age 5 to 20 years were simulated on those initial densities with the highest NPP (3000 and 4000 stems ha−1. Planting 4000 stems ha−1 and not applying thinning achieved the highest annual NPP (14.39 ± 3.92 Mg ha−1 yr−1 during the first rotation, but it was not significantly different from the NPP achieved with the same initial density but thinning 40% of trees at year 10. NPP was estimated to decrease with consecutive rotations, and for the second rotation thinning was needed to significantly increase NPP (10.11 ± 2.59 Mg ha−1 yr−1 with 4000 stems ha−1 and 25% thinning at year 10 above non-thinning management. For the third rotation, the highest NPP was reached with initial density 3000 stems ha−1 and 25% thinning at year 10. Nitrogen flows were also estimated to decrease with consecutive rotations. These results indicate the potential of managing M. glyptostroboides urban plantations to reach their maximum productivity potential, but also that additional

  10. Private valuation of carbon sequestration in forest plantations

    Energy Technology Data Exchange (ETDEWEB)

    Guitart, A. Bussoni [Facultad de Agronomia, Universidad de la Republica. Avda. E. Garzon, 780, CP 12.900, Montevideo (Uruguay); Rodriguez, L.C. Estraviz [Escola Superior de Agricultura ' ' Luiz de Queiroz' ' , Universidad de Sao, Paulo (Brazil)

    2010-01-15

    Approval of the Clean Development Mechanism, provided for in the Kyoto Protocol, enables countries with afforested land to trade in carbon emissions reduction certificates related to carbon dioxide equivalent quantities (CO{sub 2-e}) stored within a certain forest area. Potential CO{sub 2-e} above base line sequestration was determined for two forest sites on commercial eucalyptus plantations in northern Brazil (Bahia). Compensation values for silvicultural regimes involving rotation lengths greater than economically optimal were computed using the Faustmann formula. Mean values obtained were US$8.16 (MgCO{sub 2-e}){sup -} {sup 1} and US$7.19 (MgCO{sub 2-e}){sup -} {sup 1} for average and high site indexes, respectively. Results show that carbon supply is more cost-efficient in highly productive sites. Annuities of US$18.8 Mg C{sup -} {sup 1} and US$35.1 Mg C{sup -} {sup 1} and yearly payments of US$4.4 m{sup -} {sup 3} and US$8.2 m{sup -} {sup 3} due for each marginal cubic meter produced were computed for high and average sites, respectively. The estimated value of the tonne of carbon defines minimum values to be paid to forest owners, in order to induce a change in silvicultural management regimes. A reduction of carbon supply could be expected as a result of an increase in wood prices, although it would not respond in a regular manner. For both sites, price elasticity of supply was found to be inelastic and increased as rotation length moved further away from economically optimal: 0.24 and 0.27 for age 11 years in average- and high-productivity sites, respectively. This would be due to biomass production potential as a limiting factor; beyond a certain threshold value, an increase in price does not sustain a proportional change in carbon storage supply. The environmental service valuation model proposed might be adequate for assessing potential supply in plantation forestry, from a private landowner perspective, with an economic opportunity cost. The model is

  11. Ecological Stoichiometric Characteristics of Two Typical Plantations in the Karst Ecosystem of Southwestern China

    Directory of Open Access Journals (Sweden)

    Danbo Pang

    2018-01-01

    Full Text Available Reforestation has been widely adopted to restore soil fertility and ecosystem service function in the rocky desertification region of southwestern China. However, there has been limited research concerning the stoichiometry of carbon (C, nitrogen (N, and phosphorus (P and nutrient resorption rate of plantations in karst ecosystems. In this study, we selected plantations of Pinus yunnanensis Franch. (PY and Eucalyptus maideni F. Muell. (EM in Yunnan Province. The C, N, and P concentrations and the C:N:P stoichiometry in different soil layers (0–10 cm, 10–20 cm, and 20–30 cm were examined. The nutrient limitation and nutrient resorption efficiency were also analyzed. The leaf C and N concentrations in the PY plantation were higher than that in the EM plantation; the P concentration demonstrated the opposite trend, both in green and senesced leaves. Soil C, N, and P concentrations in the EM plantation were much greater than in the PY plantation at all three depths and decreased with the depth of the soil. In addition, the high ratios of C:P, N:P, C:Available P, and N:Available P in soil coupled with the ratios of N:P in leaves indicate that the EM plantation has a greater P deficiency than the PY plantation. In the EM plantation, the relatively low P concentrations in senesced leaves indicates efficient TP (Total phosphorus resorption, which highlights that the high reuse proficiency of P could have favored moderating P limitation in the karst ecosystem. This research aids in understanding the stoichiometric characteristics that mediate forest properties, and provides a basis for management of vegetation in karst ecosystems.

  12. Energy dynamics and bioenergy production of Populus deltoides G-3 Marsh plantation in eastern India

    Energy Technology Data Exchange (ETDEWEB)

    Das, D.K. [Department of Forestry, Rajendra Agricultural University, Pusa 848 125 Samastipur, Bihar (India); Chaturvedi, O.P. [National Research Centre for Agroforestry, Jhansi 284 003, UP (India)

    2009-01-15

    The energy content of stems, branches, roots and litter was determined using an oxygen bomb calorimeter, and these data were used to estimate energy storage, net energy fixation and energy transfer within poplar (Populus deltoides G-3 Marsh) plantations of two ages at the Research Farm of Rajendra Agricultural University, Pusa, Bihar, India. Energy fixation, storage and energy released and exit from the 7-year-old plantation were 1.69, 2.11 and 1.53 times that of the 5-year-old plantation. The net energy fixation was 243.08 GJ ha{sup -1} year{sup -1} in 5-year-old and 410.57 GJ ha{sup -1} year{sup -1} in 7-year-old plantation. The energy conservation efficiency in the 7-year-old plantation was higher (1.51%) than that of the 5-year-old plantation (0.89%). The 5-year-old plantation showed lower energy accumulation ratio (2.02) resulting from less energy accumulation in components of poplar tree and greater annual turnover in terms of litter fall. The energy stored in the above-ground tree components from 2131.87 ha (5-year old) and 1002.88 ha (7-year old) or in the above-ground net annual production from 3924.15 ha (5-year old) and 2386.37 ha (7-year old) of poplar plantations is sufficient to operate a 5 MW generating station for 1 year. Above-ground biomass and net production from 1 ha of 5-year-old and 7-year-old poplar plantations is sufficient to meet the energy need of an average household in eastern India for 8.5 and 18.0 years and 4.6 and 7.6 years, respectively. (author)

  13. Changes in soil quality after converting Pinus to Eucalyptus plantations in southern China

    Science.gov (United States)

    Zhang, K.; Zheng, H.; Chen, F. L.; Ouyang, Z. Y.; Wang, Y.; Wu, Y. F.; Lan, J.; Fu, M.; Xiang, X. W.

    2015-02-01

    Vegetation plays a key role in maintaining soil quality, but long-term changes in soil quality due to plant species change and successive planting are rarely reported. Using the space-for-time substitution method, adjacent plantations of Pinus and first, second, third and fourth generations of Eucalyptus in Guangxi, China were used to study changes in soil quality caused by converting Pinus to Eucalyptus and successive Eucalyptus planting. Soil chemical and biological properties were measured and a soil quality index was calculated using principal component analysis. Soil organic carbon, total nitrogen, alkaline hydrolytic nitrogen, microbial biomass carbon, microbial biomass nitrogen, cellobiosidase, phenol oxidase, peroxidase and acid phosphatase activities were significantly lower in the first and second generations of Eucalyptus plantations compared with Pinus plantation, but they were significantly higher in the third and fourth generations than in the first and second generations and significantly lower than in Pinus plantation. Soil total and available potassium were significantly lower in Eucalyptus plantations (1.8-2.5 g kg-1 and 26-66 mg kg-1) compared to the Pinus plantation (14.3 g kg-1 and 92 mg kg-1), but total phosphorus was significantly higher in Eucalyptus plantations (0.9-1.1 g kg-1) compared to the Pinus plantation (0.4 g kg-1). As an integrated indicator, soil quality index was highest in the Pinus plantation (0.92) and lowest in the first and second generations of Eucalyptus plantations (0.24 and 0.13). Soil quality index in the third and fourth generations (0.36 and 0.38) was between that in Pinus plantation and in first and second generations of Eucalyptus plantations. Changing tree species, reclamation and fertilization may have contributed to the change observed in soil quality during conversion of Pinus to Eucalyptus and successive Eucalyptus planting. Litter retention, keeping understorey coverage, and reducing soil disturbance during

  14. Winter ecology of a subalpine grassland: Effects of snow removal on soil respiration, microbial structure and function.

    Science.gov (United States)

    Gavazov, Konstantin; Ingrisch, Johannes; Hasibeder, Roland; Mills, Robert T E; Buttler, Alexandre; Gleixner, Gerd; Pumpanen, Jukka; Bahn, Michael

    2017-07-15

    Seasonal snow cover provides essential insulation for mountain ecosystems, but expected changes in precipitation patterns and snow cover duration due to global warming can influence the activity of soil microbial communities. In turn, these changes have the potential to create new dynamics of soil organic matter cycling. To assess the effects of experimental snow removal and advanced spring conditions on soil carbon (C) and nitrogen (N) dynamics, and on the biomass and structure of soil microbial communities, we performed an in situ study in a subalpine grassland in the Austrian Alps, in conjunction with soil incubations under controlled conditions. We found substantial winter C-mineralisation and high accumulation of inorganic and organic N in the topsoil, peaking at snowmelt. Soil microbial biomass doubled under the snow, paralleled by a fivefold increase in its C:N ratio, but no apparent change in its bacteria-dominated community structure. Snow removal led to a series of mild freeze-thaw cycles, which had minor effects on in situ soil CO2 production and N mineralisation. Incubated soil under advanced spring conditions, however, revealed an impaired microbial metabolism shortly after snow removal, characterised by a limited capacity for C-mineralisation of both fresh plant-derived substrates and existing soil organic matter (SOM), leading to reduced priming effects. This effect was transient and the observed recovery in microbial respiration and SOM priming towards the end of the winter season indicated microbial resilience to short-lived freeze-thaw disturbance under field conditions. Bacteria showed a higher potential for uptake of plant-derived C substrates during this recovery phase. The observed temporary loss in microbial C-mineralisation capacity and the promotion of bacteria over fungi can likely impede winter SOM cycling in mountain grasslands under recurrent winter climate change events, with plausible implications for soil nutrient availability and

  15. Distribution Pattern, Conservation Status, and Associated Flora of the Genus Juniperus in Subalpine Pastures of the Kashmir Himalayas

    Directory of Open Access Journals (Sweden)

    Hamayun Shaheen

    2017-11-01

    Full Text Available Juniperus is an evergreen gymnosperm genus with a broad geographical distribution in the Northern Hemisphere. Juniperus constitutes important vegetation associations in the Himalayan highlands that have significant ecological and socioeconomic importance. This research investigated the distribution pattern, community structure, and ecosystem services provided byJuniperus -dominated subalpine vegetation in the upper Neelum Valley, Pakistan. Vegetation attributes and geographical characteristics were systematically recorded at 4 selected sites. Two species of Juniperus, Juniperus communis L. and J. excelsa M. Bieb., were found to have average importance values of 23.4 and 20.02%, respectively. J. excelsa showed an average basal area of 0.30 m2 ha−1 and an average stem density of 46.95 ha−1; J. communis had an average basal area of 0.25 m2 ha−1 and an average stem density of 33.21 ha−1. A total of 56 Juniperus-associated plant species from 29 families were recorded, with Asteraceae as the dominant family, followed by Lamiaceae, Polygonaceae, Rosaceae, Caryophyllaceae, and Apiaceae. Predominant associated species included Thymus linearis, Aster falconeri, Rosa webbiana, Berberis lyceum, Anagallis arvensis, Rumex nepalensis, Poa alpina, Bistorta affinis, and Iris hookeriana. The calculated average values were Shannon's diversity, 3.07; Simpson's diversity, 0.94; species richness, 1.11; species evenness, 0.90; and maturity index, 45.90. Hemicryptophytes were the dominant lifeform in the area (57.14%, and microphylls (46.42% were the dominant leaf type. Overgrazing and fuelwood cutting were identified as serious threats to both Juniperus species. Restoration of the degraded juniper stands through collective efforts by government and local communities and regular monitoring is recommended.

  16. Thirty Years of Change in Subalpine Forest Cover from Landsat Image Analysis in the Sierra Nevada Mountains of California

    Science.gov (United States)

    Potter, Christopher

    2015-01-01

    Landsat imagery was analyzed to understand changes in subalpine forest stands since the mid-1980s in the Sierra-Nevada region of California. At locations where long-term plot measurements have shown that stands are becoming denser in the number of small tree stems (compared to the early 1930s), the 30-year analysis of Landsat greenness index (NDVI) indicated that no consistent increases in canopy leaf cover have occurred at these same locations since the mid-1980s. Interannual variations in stand NDVI closely followed snow accumulation amounts recorded at nearby stations. In contrast, at eastern Sierra whitebark pine stand locations where it has been observed that widespread tree mortality has occurred, decreasing NDVI trends over the past 5-10 years were consistent with rapid loss of forest canopy cover. Landsat imagery was further analyzed to understand patterns of post-wildfire vegetation recovery, focusing on high burn severity (HBS) patches within burned areas dating from the late 1940s. Analysis of landscape metrics showed that the percentage of total HBS area comprised by the largest patch of recovered woody cover was relatively small in all fires that occurred since 1995, but increased rapidly with time since fire. Patch complexity of recovered woody cover decreased notably after more than 50 years of regrowth, but was not readily associated with time for fires that occurred since the mid 1990s. The aggregation level of patches with recovery of woody cover increased steadily with time since fire. The study approach using satellite remote sensing can be expanded to assess the consequences of stand-replacing wildfires in all forests of the region.

  17. Vegetation types and climate conditions reflected by the modern phytolith assemblages in the subalpine Dalaoling Forest Reserve, central China

    Science.gov (United States)

    Traoré, Djakanibé Désiré; Gu, Yansheng; Liu, Humei; Shemsanga, Ceven; Ge, Jiwen

    2015-06-01

    This research describes modern phytolith records and distributions from subalpine surface soils in the Dalaoling Forest Reserve, and reveals its implications for local climate conditions with respect to the altitude gradient. Well-preserved phytolith morpho-types, assemblages, and climatic indices were used to study the relationship between local vegetation and climate conditions. The phytolith classification system is mainly based on the characteristics of detailed morpho-types described for anatomical terms, which are divided into seven groups: long cells, short cells, bulliform cells, hair cells, pteridophyte type, broad-leaved type, and gymnosperm type. Phytoliths originating from the Poaceae are composed of Pooideae (rondel and trapeziform), Panicoideae (bilobate, cross, and polylobate), Chloridoideae (short/square saddle), and Bambusoideae (oblong concave saddle). Based on the altitudinal distribution of the phytolith assemblages and the indices of aridity (Iph), climate (Ic), and tree cover density (D/P), five phytolith assemblage zones have revealed the five types of climatic conditions ranging from 1,169 m to 2,005 m in turn: warm-wet, warm-xeric to warm-mesic, warm-xeric to cool-mesic, cool-xeric, and cool-mesic to cool-xeric. The Bambusoideae, Panicoideae, and Chloridoideae are the dominant vegetation at the lower-middle of the mountains, while Pooideae is mainly distributed in the higher mountains. The close relationship between phytolith assembleages and changes of altitude gradient suggest that vegetation distribution patterns and plant ecology in the Dalaoling mountains are controlled by temperature and humidity conditions. Our results highlight the importance of phytolith records as reliable ecoclimatic indicators for vegetation ecology in subtropical regions.

  18. Mycorrhiza-plant colonization patterns on a subalpine glacier forefront as a model system of primary succession.

    Science.gov (United States)

    Cázares, Efrén; Trappe, James M; Jumpponen, Ari

    2005-09-01

    Lyman glacier in the North Cascades Mountains of Washington has a subalpine forefront characterized by a well-developed terminal moraine, inconspicuous successional moraines, fluting, and outwash. These deposits were depleted of symbiotic fungi when first exposed but colonized by them over time after exposure. Four major groups of plant species in this system are (1) mycorrhiza-independent or facultative mycotrophic, (2) dependent on arbuscular mycorrhizae (AM) (3) dependent on ericoid mycorrhiza (ERM) or ectomycorrhizae (EM), and (4) colonized by dark-septate (DS) endophytes. We hypothesized that availability of mycorrhizal propagules was related to the success of mycorrhiza-dependent plants in colonizing new substrates in naturally evolved ecosystems. To test this hypothesis roots samples of 66 plant species were examined for mycorrhizal colonization. The plants were sampled from communities at increasing distances from the glacier terminus to compare the newest communities with successively older ones. Long established, secondary successional dry meadow communities adjacent to the glacier forefront, and nearby high alpine communities were sampled for comparison. DS were common on most plant species on the forefront. Nonmycorrhizal plants predominated in the earlier successional sites, whereas the proportion of mycorrhizal plants generally increased with age of community. AM were present, mostly at low levels, and nearly absent in two sites of the forefront. ERM were present in all species of Ericaceae sampled, and EM in all species of Pinaceae and Salicaceae. Roots of plants in the long established meadow and heath communities adjacent to the forefront and the high alpine community all had one or another of the colonization types, with DS and AM predominating.

  19. What causes the density effect in young forest plantations?

    Energy Technology Data Exchange (ETDEWEB)

    Barbara J. Bond; Gary A. Ritchie

    2002-07-21

    In young forest plantations, trees planted at high densities frequently show more rapid height and diameter growth than those plants at lower densities. This positive growth response to density (the ''density effect'') often manifests long before seedlings are tall enough to shade one another, so it is not a simple response to shade. The mechanism(s) which trigger and sustain this growth enhancement are unknown. Our objectives were to document the temporal dynamics of positive growth response to increasing density in Douglas-fir plantations and to test two hypotheses as potential mechanisms for this response. The hypotheses are (1) a canopy boundary layer effect, and (2) alterations in the quality of light reflected from neighboring trees. The ''boundary layer'' hypotheses proposes that changes in atmospheric mixing occur in high-density plantations, promoting increased concentrations of CO{sub 2} and H{sub 2}O vapor during early morning hours, which in turn would enhance carbon assimilation. The ''light quality'' hypothesis proposes that the presence of neighbors alters the ratio of red to far red light in the canopy environment. Plant sensors detect this change in light quality, and growth and development is altered in response. We found that boundary layer conductance was higher, as we predicted, in low-density Douglas-fir stands than in high-density stands five years after planting. The changes in boundary conductance were accompanied by higher CO{sub 2} and H{sub 2}O vapor during early morning hours. However, we also found that the primary manifestation of the density effect in Douglas-fir occurs two to four years after planting, and we were not able to measure differences in boundary conductance in different densities at that time. Also, we found no difference in carbon isotope composition of wood cellulose formed in high- vs. low-density stands two to three years after planting. We conclude that

  20. Evaluation of Mycosphaerella impact on eucalypts plantations in Portugal

    Directory of Open Access Journals (Sweden)

    Márcia Silva

    2008-12-01

    Full Text Available Mycosphaerella leaf disease (MLD is one of the most important diseases of eucalypts plantations worldwide. However, only recently it has become relevant in Portugal. Caused by a complex of Mycosphaerella species, this disease reduces the photosynthetic area and can cause tree defoliation. In extreme cases it causes reduction in the volume of wood produced. In order to relate the observed symptoms of MLD with the presence of the pathogen and at the same time obtaining an evaluation of eucalypt clones and family susceptibility, two experimental plantations were established in places where the disease has been detected. Data on the percentage of affected crown (necrosis or defoliation were collected and some of the Mycosphaerella species present were identified (M. africana, M. communis, M. grandis, M. lateralis, M. marksii, M. nubilosa, M. parva, M. vespa and M. walkeri.A doença das manchas das folhas do eucalipto é uma das mais importantes nas plantações de eucalipto, tendo-se só recentemente tornado relevante em Portugal. Esta doença, causada por um complexo de espécies de Mycosphaerella, reduz a área fotossintética da árvore, podendo causar desfolha, com consequente redução da taxa de crescimento e do volume de madeira produzido. Com o objectivo de relacionar os sintomas observados com a presença do agente patogénico e avaliar a susceptibilidade de clones e famílias de eucalipto, foram estabelecidas duas plantações experimentais em locais onde foi detectada a doença. Foram recolhidos dados relativos à percentagem de área da copa afectada (por necroses ou desfolha e identificadas as espécies de Mycosphaerella associadas (M. africana, M. communis, M. grandis, M. lateralis, M. marksii, M. nubilosa, M. parva, M. vespa e M. walkeri.

  1. Albedo of a hybrid poplar plantation in central Alberta, Canada

    Science.gov (United States)

    Price, D. T.; Bernier, P. Y.; Orchansky, A.; Thomas, B.

    2012-04-01

    Canada's boreal forest resources are coming under increasing pressure from competing land-uses, including establishment of protected areas, and losses of harvestable forest to mining and oil and gas exploration. In the prairie region, concerns about lack of wood supply for pulpmills and potential opportunities for bioenergy production and carbon sequestration for climate change mitigation, have spurred interest in afforestation of marginal agricultural land, notably with fast-growing hybrid poplars (HP). However, global modelling studies suggest that a shift from grassland or crops to forest cover in temperate and boreal regions could result in reduced surface albedo, particularly in winter, causing an increase in radiative forcing and reducing any climate mitigation benefits due to net GHG removal. We report on seven growing seasons of measurements of short-wave canopy albedo using tower-mounted instruments, along with eddy covariance measurements of carbon, water and energy balance, at a site in central Alberta planted with HP cuttings in spring 2005. The data show little systematic change in average albedo as vegetation has changed from bare ground to a plantation of 6 m trees. Reasons for this include very wide (3 m) spacing between the trees, and snow cover which often persists for 4-5 months and is highly visible below the bare canopies during winter. While measurements should continue as the trees grow larger, we postulate that extensive afforestation with HP is unlikely to have major effects on regional-scale surface albedo compared to the agricultural systems they replace. Normal rotation lengths are 15-20 years, hence even if older plantations have significantly lower winter albedo, their contribution to the regional average would be relatively small because they will cover only a small fraction of the landscape (e.g., compared to forests of boreal conifers or temperate broadleaved species).

  2. ECONOMIC ROTATION OF Eucalyptus grandis PLANTATIONS FOR PULP PRODUCTION

    Directory of Open Access Journals (Sweden)

    Thais Cunha Ferreira

    2004-07-01

    Full Text Available The objectives of the research were: to determine the economic impact of several minimum diameter and length of logs in economic rotation age, economic feasibility of Eucalyptus grandis plantation for cellulose production; to determine the economic loss of cutting the stand before or after the optimal economic rotation age. A biometric model for making wood volume prognosis was developed using data of a trial of Eucalyptus grandis plantation envisaging pulp production. Eucalyptus grandis stands of 19 and 103 months old, in the spacing 3 x 2 and 3 x 3 m in site index of 30; 28; 26 and 24 m were used. Theprognosis started at the age zero, considering logs of 2.5; 2.8; 4.0 and 6.0 m of length for minimum diameter varying from 4 to 10 cm, in intervals of 2 cm. Net Present Worth (VPL was used the economic criterion, considering an infinite horizon and a cost relation including reestablishment, yearly maintenance, logging and wood transportation costs. The main conclusions were: increases in the minimum diameter and or in logs length increase the rotation age; harvesting the stands in ages different from the optimal one cause large economic loss mainly in the better sites; the economic loss is larger if the harvest is made before the optimal economic rotation than if it is make after; economic feasibility increases when the minimum diameter is smaller and when the length of the logs is shorter. Any way, before making any decision it is necessary to take into account possible technical restrictions and effect on harvest and transportation costs caused by changer in the length of logs and in the size of the minimum commercial diameter.

  3. Native forest generation in pine and eucalypt plantation in Northern Province, South Africa

    CSIR Research Space (South Africa)

    Geldenhuys, CJ

    1997-12-01

    Full Text Available Commercial plantations in South Africa have been established mainly in grasslands adjacent to native forest which occur as small, scattered patches, restricted to valleys and scarps by regular fire-prone grasslands. Under storey vegetation...

  4. Tree size predicts vascular epiphytic richness of traditional cultivated tea plantations in Southwestern China

    National Research Council Canada - National Science Library

    Qing Wang; Wen-Bin Guan; Michelle Hang Gi Wong; Sailesh Ranjitkar; Wei-Na Sun; Yao Pan; Yousry A. El-Kassaby; Li-Xin Shen

    2017-01-01

    .... Epiphytic plants are plentiful on ancient tea trees (Camelia sinensis var. assamica) in the well-known Jingmai tea plantation area, Langcang region of Yunnan Province, SW China, and add to the plant community biodiversity...

  5. Atlantic Rainforest Remnant Harbors Greater Biotic Diversity but Reduced Lepidopteran Populations Compared to a Eucalyptus Plantation

    National Research Council Canada - National Science Library

    Onice Teresinha Dall'Oglio; Teresinha Vinha Zanuncio; Wagner De Souza Tavares; José Eduardo Serrão; Carlos Frederico Wilcken; José Cola Zanuncio

    2013-01-01

    ...) collected with 5 light traps (replicates) in different habitats. The first and second traps were installed in a eucalyptus plantation at 400 and 200 m, respectively, from the interface with a native vegetation area (Atlantic Rainforest...

  6. First Report of the Occurrence of Weevils (Insecta: Coleoptera) in Plantations of Green Tea in Brazil

    National Research Council Canada - National Science Library

    Eduardo Suguino; Terezinha Monteiro Dos Santos-Cividanes; Francisco Jorge Cividanes; Ana Maria De Faria; Adriana Novais Martins

    2013-01-01

    ...) in tea plantations in the municipality of São Miguel Arcanjo, SP, Brazil. The damage caused by these insects is related mainly to the presence of insect fragments in dried tea leaves, hindering the marketing of the product...

  7. Reproduction of Oncidium poikilostalix (Orchidaceae), potentially invading coffee plantations in Soconusco, Chiapas, México

    National Research Council Canada - National Science Library

    Alfredo García-González; Anne Damon; Francisco A. Iturbide; Víctor Olalde-Portugal

    2013-01-01

    Context - Oncidium poikilostalix (Kraenzl.) M.W.Chase & N.H.Williams (Orchidaceae) was first reported in Mexico in 2008 and grows on coffee bushes in shaded plantations in Soconusco region in southeast Mexico...

  8. Challenges and advances in genetically improving trees for the plantation forestry sector

    CSIR Research Space (South Africa)

    Verryn, SD

    2010-08-30

    Full Text Available This presentation outlines the South African plantation forestry sector and its contributions and improvement in productivity, acquiring genetic diversity, challenges and advances in genetically improving trees as well as transforming the value...

  9. Uso dello spazio da parte dello scoiattolo comune (Sciurus vulgaris in bosco di conifere

    Directory of Open Access Journals (Sweden)

    M. Adamo

    2003-10-01

    Full Text Available Nell?ambito di un progetto di ricerca sull?ecologia dello scoiattolo comune in boschi di conifere delle Alpi, abbiamo avviato uno studio con la radiotelemetria per indagare i fattori che influiscono sull?uso dello spazio da parte degli animali. I risultati riportati nel presente lavoro si riferiscono a due anni successivi caratterizzati da una diversa disponibilità alimentare. L?area di studio si trovava nel Parco Nazionale del Gran Paradiso, in Val di Rhemes, all?interno di una pecceta subalpina (Picea abies 85%, Larix decidua 11%, alberi morti 4%. La produzione energetica del bosco (semi delle conifere è stata valutata moltiplicando il n. di piante per ettaro x il n. medio di coni prodotti (contati su 60 alberi campione x il n. medio di semi per cono x il peso medio dei semi, trasformando poi la biomassa in Mj. Le catture sono state effettuate tre volte l?anno nel 2001 e 2002 con 30 trappole incruente Tomahawk tipo 201. Diciotto scoiattoli nel 2001 e 13 nel 2002 sono stati dotati di radiocollare (PD-2C Holohil Systems Ltd. e seguiti in estate e autunno. Sono stati calcolati i seguenti parametri: home range MCP 100%, MCP 95% (animali con singole escursioni, 100% Cluster-based (animali che usavano differenti aree di attività; stime delle core-area mono e multinucleari effettuate con la tecnica della Cluster Analysis 85%; sovrapposizione delle core-area. Nel 2001, all?inizio dell?estate, 4 maschi su 8 e 7 femmine su 8 sono emigrati nella valle adiacente o a quote più basse. Nel 2002, tutti gli individui sono rimasti residenti. La dimensione media degli home range stagionali nel 2001 è stata di 83,30 ± 48,72 ha (n = 30 contro 31,04 ± 16,65 ha (n = 19 nel 2002, la media delle core-area è stata 18,18 ± 17,74 ha nel 2001 e 9,36 ± 5,40 ha in 2002 (Kruskal-Wallis ANOVA: home range H = 22,6; g.l. = 1, P < 0,0001; core-area H = 4,55, g.l. = 1, P = 0,033. La sovrapposizione delle core-area maschio/femmina e femmina/maschio

  10. Losses of soil carbon by converting tropical forest to plantations: erosion and decomposition estimated by δ(13) C.

    Science.gov (United States)

    Guillaume, Thomas; Damris, Muhammad; Kuzyakov, Yakov

    2015-09-01

    Indonesia lost more tropical forest than all of Brazil in 2012, mainly driven by the rubber, oil palm, and timber industries. Nonetheless, the effects of converting forest to oil palm and rubber plantations on soil organic carbon (SOC) stocks remain unclear. We analyzed SOC losses after lowland rainforest conversion to oil palm, intensive rubber, and extensive rubber plantations in Jambi Province on Sumatra Island. The focus was on two processes: (1) erosion and (2) decomposition of soil organic matter. Carbon contents in the Ah horizon under oil palm and rubber plantations were strongly reduced up to 70% and 62%, respectively. The decrease was lower under extensive rubber plantations (41%). On average, converting forest to plantations led to a loss of 10 Mg C ha(-1) after about 15 years of conversion. The C content in the subsoil was similar under the forest and the plantations. We therefore assumed that a shift to higher δ(13) C values in plantation subsoil corresponds to the losses from the upper soil layer by erosion. Erosion was estimated by comparing the δ(13) C profiles in the soils under forest and under plantations. The estimated erosion was the strongest in oil palm (35 ± 8 cm) and rubber (33 ± 10 cm) plantations. The (13) C enrichment of SOC used as a proxy of its turnover indicates a decrease of SOC decomposition rate in the Ah horizon under oil palm plantations after forest conversion. Nonetheless, based on the lack of C input from litter, we expect further losses of SOC in oil palm plantations, which are a less sustainable land use compared to rubber plantations. We conclude that δ(13) C depth profiles may be a powerful tool to disentangle soil erosion and SOC mineralization after the conversion of natural ecosystems conversion to intensive plantations when soils show gradual increase of δ(13) C values with depth. © 2015 The Authors. Global Change Biology published by John Wiley & Sons Ltd.

  11. Soil organic matter on citrus plantation in Eastern Spain

    Science.gov (United States)

    Cerdà, Artemi; Pereira, Paulo; Novara, Agata; Prosdocimi, Massimo

    2015-04-01

    Citrus plantations in Eastern Spain are the main crop and Valencia region is the largest world exporter. The traditional plantation are located on flood irrigated areas and the new plantation are located on slopes were drip irrigation is the source of the wetting. It has been demonstrate that the citrus plantations contribute to high erosion rates on slopes (Cerdà et al., 2009b) as it is usual on agriculture land (Cerdà et al., 2009a), but when organic farming is present the soil erosion is much lower (Cerdà and Jurgensen, 2008; Cerdà et al., 2009; Cerdà and Jurgensen, 2011). This is a worldwide phenomenon (Wu et al., 2007; Wu et al., 2011; Xu et al., 2010; Xu et al., 2012a; Xu et al., 2012b), which are a key factor of the high erosion rates in rural areas (García Orenes et al., 2009: García Orenes et al., 20010; García Orenes et al., 2012; Haregewyn et al., 2013; Zhao et al., 2013). The key factor of the contrasted response of soils to the rain in citrus is the organic matter cover. This is why the Soil Erosion and Degradation Research Team developed a survey to determine the soil erosion rates on citrus orchards under different managements. A hundred of samples were collected in a citrus plantation on slope under conventional management (Chemical management), one on organic farming, one on traditional flood irrigated organic farming and one on traditional chemical flooding farm. The organic farming soils were treated with 10000 Kg ha-1 of manure yearly. The results show that the mean soil organic matter content was 1.24 %, 3.54%, 5,43% and 2.1% respectively, which show a clear impact of organic farming in the recovery of the soil organic matter. meanwhile the on the slopes and the flood-irrigated soils are Acknowledgements The research projects GL2008-02879/BTE, LEDDRA 243857 and PREVENTING AND REMEDIATING DEGRADATION OF SOILS IN EUROPE THROUGH LAND CARE (RECARE)FP7- ENV-2013- supported this research. References Cerdà, A., Flanagan, D.C., le Bissonnais

  12. Study of influence of 2.4 GHz electromagnetic waves on electrophysical properties of coniferous trees wood

    Science.gov (United States)

    Abdurahimov, Nursulton; Lagunov, Alexey; Melehov, Vladimir

    2017-09-01

    Climate change has a significant impact on changing weather conditions in the Arctic. Wood is a traditional building material in the North of Russia. Supports of communication lines are made of wood. Dry wood is a solid dielectric with a low conductivity. At the same time it is porous material having high hygroscopicity. The presence of moisture leads to wood rotting. To prevent rotting of a support it needs to be impregnated with antiseptics. A tree dried by means of convection drying cannot provide required porosity of wood for impregnation. Our studies of electrophysical properties of coniferous species showed that microwave drying of wood increases the porosity of the wood. Wood dried in this way is easily impregnated with antiseptics. Thorough wood drying requires creating optimal conditions in a microwave oven. During the drying process in a chamber there is a resonant phenomenon. These phenomena depend on electro-physical properties of the material placed in the chamber. Dielectric constant of wood has the most influence. A resonator method to determine the dielectric constant of the wood was used. The values of permittivity for the spruce and pine samples were determined. The measured value of the dielectric constant of wood was used to provide optimal matching of the generator with the resonator in a wood-drying resonator type microwave chamber, and to maintain it in the process of wood drying. It resulted in obtaining the samples with a higher permeability of wood in radial and longitudinal direction. This creates favorable conditions for wood impregnation with antiseptics and flame retardants. Timber dried by means of electromagnetic waves in the 2.4 GHz band has a deeper protective layer. The support made of such wood will serve longer as supports of communication lines.

  13. Isoprene Nitrate Chemistry in a Mixed Coniferous/Deciduous Forest during the 2016 PROPHET-AMOS Summer Field Study

    Science.gov (United States)

    Desrochers, S. J.; Slade, J. H., Jr.; Shepson, P. B.; Alwe, H. D.; Millet, D. B.; Kavassalis, S.; Shi, Q.; Murphy, J. G.; Bloss, W.; Wood, E. C. D.; Wennberg, P. O.; Bertman, S. B.; Stevens, P. S.

    2016-12-01

    Isoprene, the most abundant biogenic volatile organic compound emitted from forest ecosystems, represents a significant sink for atmospheric organic nitrogen. The formation of isoprene nitrates by the oxidation of isoprene in the presence of NOx influences global concentrations of NOx and ozone, and can be a major precursor to secondary organic aerosol. Measurements of isoprene nitrates in the ambient environment are sparse, however, and present an analytical challenge. In part, this is due to the influence of isomeric species on the sensitivity of commonly employed mass spectrometry techniques, including chemical ionization mass spectrometry (CIMS), and the availability of standards. Here, we present results from the 2016 PROPHET-AMOS summer field study in northern Michigan on the atmospheric chemistry of isoprene hydroxynitrates (IN) both at and below the canopy level using a single-quadrupole CIMS. The PROPHET research site is unique in that it is currently undergoing a succession from predominantly deciduous, and thus primarily isoprene emitting, to coniferous, primarily monoterpene emitting. Preliminary results indicate that IN production reaches a maximum in the early afternoon of approximately 40-50 ppt on average, driven by NO chemistry. This is relatively low compared to, for example, the SOAS site, owing to the relative availability of NO in this pristine atmosphere in northern Michigan. However, concentrations can remain high past midnight, possibly due to the influence of NO3 chemistry, poor vertical mixing in the evening, or slow deposition. Between the two inlets, the within-canopy inlet demonstrated higher [IN], indicative of canopy-scale isoprene-NOx chemistry; however, the vertical gradients can be more homogeneous depending on the meteorological conditions. Using supplemental measurements of OH, NOx, O3, HO2, and isoprene, we apply a 0-D box model to simulate the production of IN at the PROPHET site, to better understand the influence of local

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

    Science.gov (United States)

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

    2005-09-01

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

  15. Natural coniferous resin salve used to treat complicated surgical wounds: pilot clinical trial on healing and costs.

    Science.gov (United States)

    Sipponen, Arno; Kuokkanen, Opri; Tiihonen, Raine; Kauppinen, Harri; Jokinen, Janne J

    2012-06-01

    Resin is a natural product of coniferous trees. Salves manufactured from spruce resin (Picea abies) have been used for centuries to treat wounds and skin infections. We report a pilot clinical trial designed to investigate healing rates, factors that contribute to delayed wound healing, cost-effectiveness, and incidence of allergic reactions when resin salve is used to treat complicated surgical wounds. The trial involved 23 patients in whom wound healing after surgery was delayed. These patients were assigned to resin salve treatment. The primary outcome measure was the number of days to complete wound healing. Secondary objectives included an assessment of factors contributing to delayed wound healing, an estimation of associated costs, and an investigation into the occurrence of allergic reactions related to resin salve therapy. The study achieved a healing rate of 100%. The mean ± SD healing time was 43 ± 24 days. The mean ± SD wound size (length × width × depth) was (29 ± 19) × (12 ± 7) × (4 ± 3) mm. Wound size, use of corticosteroids or other immunosuppressants, and immobilization were statistically significant (P resin salve treatment were €45.0 ± 26.0 per patient during the entire treatment period and €1.2 ± 0.5 per treatment day. The rate of allergic reactions was 0%. The results of this pilot trial indicate that complicated surgical wounds may be treated successfully with resin salve. The treatment method is clinically effective and cost-effective, and the rate of allergic reactions is low. © 2012 The International Society of Dermatology.

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

    Science.gov (United States)

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

    2016-12-01

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

  17. Deposition velocity of PM2.5 in the winter and spring above deciduous and coniferous forests in Beijing, China.

    Science.gov (United States)

    Sun, Fengbin; Yin, Zhe; Lun, Xiaoxiu; Zhao, Yang; Li, Renna; Shi, Fangtian; Yu, Xinxiao

    2014-01-01

    To estimate the deposition effect of PM2.5 (particle matter with aerodynamic diameter forests in northern China, we used the gradient method to measure the deposition velocity of PM2.5 during the winter and spring above a deciduous forest in Olympic Forest Park and above a coniferous forest in Jiufeng National Forest Park. Six aerosol samplers were placed on two towers at each site at heights of 9, 12 and 15 m above the ground surface. The sample filters were exchanged every four hours at 6∶00 AM, 10∶00 AM, 2∶00 PM, 6∶00 PM, 10∶00 PM, and 2∶00 AM. The daytime and nighttime deposition velocities in Jiufeng Park and Olympic Park were compared in this study. The February deposition velocities in Jiufeng Park were 1.2±1.3 and 0.7±0.7 cm s-1 during the day and night, respectively. The May deposition velocities in Olympic Park were 0.9±0.8 and 0.4±0.5 cm s-1 during the day and night, respectively. The May deposition velocities in Jiufeng Park were 1.1±1.2 and 0.6±0.5 cm s-1 during the day and night, respectively. The deposition velocities above Jiufeng National Forest Park were higher than those above Olympic Forest Park. The measured values were smaller than the simulated values obtained by the Ruijgrok et al. (1997) and Wesely et al. (1985) models. However, the reproducibility of the Ruijgrok et al. (1997) model was better than that of the Wesely et al. (1985) model. The Hicks et al. (1977) model was used to analyze additional forest parameters to calculate the PM2.5 deposition, which could better reflect the role of the forest in PM2.5 deposition.

  18. Movements, cover-type selection, and survival of fledgling Ovenbirds in managed deciduous and mixed coniferous-deciduous forests

    Science.gov (United States)

    Streby, Henry M.; Andersen, David E.

    2013-01-01

    We used radio telemetry to monitor movements, cover-type selection, and survival for fledglings of the mature-forest nesting Ovenbird (Seiurus aurocapilla) at two managed forest sites in north-central Minnesota. Both sites contained forested wetlands, regenerating clearcut stands of various ages, and logging roads, but differed in mature forest composition; one deciduous with open understory, and the other mixed coniferous-deciduous with dense understory. We used compositional analysis, modified to incorporate age-specific limitations in fledgling movements, to assess cover-type selection by fledglings throughout the dependent (on adult care) post-fledging period. Compared to those that were depredated, fledglings from nests in deciduous forest that survived the early post-fledging period had more older (sapling-dominated) clearcut available, directed movements toward older clearcuts and forested wetlands, and used older clearcuts more than other cover types relative to availability. Fledglings that were depredated had more young (shrub-dominated) clearcut and unpaved logging road available, and used mature forest and roads more than expected based on availability. For birds from nests in mixed mature forest with dense understory, movements and cover-type selection were similar between fledglings that survived and those that were depredated. However, fledglings that were depredated at that site also had more young clearcut available than fledglings that survived. We conclude that Ovenbird fledgling survival is influenced by distance of their nest to various non-nesting cover types, and by the subsequent selection among those cover types, but that the influence of non-nesting cover types varies depending on the availability of dense understory vegetation in mature forest.

  19. Above-Ground Biomass and Biomass Components Estimation Using LiDAR Data in a Coniferous Forest

    Directory of Open Access Journals (Sweden)

    Qisheng He

    2013-11-01

    Full Text Available This study aims to estimate forest above-ground biomass and biomass components in a stand of Picea crassifolia (a coniferous tree located on Qilian Mountain, western China via low density small-footprint airborne LiDAR data. LiDAR points were first classified into ground points and vegetation points. After, vegetation statistics, including height quantiles, mean height, and fractional cover were calculated. Stepwise multiple regression models were used to develop equations that relate the vegetation statistics from field inventory data with field-based estimates of biomass for each sample plot. The results showed that stem, branch, and above-ground biomass may be estimated with relatively higher accuracies; estimates have adjusted R2 values of 0.748, 0.749, and 0.727, respectively, root mean squared error (RMSE values of 9.876, 1.520, and 15.237 Mg·ha−1, respectively, and relative RMSE values of 12.783%, 12.423%, and 14.163%, respectively. Moreover, fruit and crown biomass may be estimated with relatively high accuracies; estimates have adjusted R2 values of 0.578 and 0.648, respectively, RMSE values of 1.022 and 5.963 Mg·ha−1, respectively, and relative RMSE values of 23.273% and 19.665%, respectively. In contrast, foliage biomass estimates have relatively low accuracies; they had an adjusted R2 value of 0.356, an RMSE of 3.691 Mg·ha−1, and a relative RMSE of 26.953%. Finally, above-ground biomass and biomass component spatial maps were established using stepwise multiple regression equations. These maps are very useful for updating and modifying forest base maps and registries.

  20. Hydrology and Water Quality of a Drained Loblolly Pine Plantation in Coastal North Carolina

    Science.gov (United States)

    Devendra M. Amatya; R. W. Skaggs; J. W. Gilliam

    2006-01-01

    This paper evaluates 17 years (1988-2004) of hydrologic and water quality data from a drained pine plantation in eastern North Carolina. The plantation age was 14 years at the beginning of the investigation (1988) and 30 years at the end of (2004). The 17-year average rainfall of 1538 mm was 11% higher that the 50-year (1951 – 2000) long-term data of 1391 mm observed...

  1. Rapid conversions and avoided deforestation: examining four decades of industrial plantation expansion in Borneo

    Science.gov (United States)

    Gaveau, David L. A.; Sheil, Douglas; Husnayaen; Salim, Mohammad A.; Arjasakusuma, Sanjiwana; Ancrenaz, Marc; Pacheco, Pablo; Meijaard, Erik

    2016-09-01

    New plantations can either cause deforestation by replacing natural forests or avoid this by using previously cleared areas. The extent of these two situations is contested in tropical biodiversity hotspots where objective data are limited. Here, we explore delays between deforestation and the establishment of industrial tree plantations on Borneo using satellite imagery. Between 1973 and 2015 an estimated 18.7 Mha of Borneo’s old-growth forest were cleared (14.4 Mha and 4.2 Mha in Indonesian and Malaysian Borneo). Industrial plantations expanded by 9.1 Mha (7.8 Mha oil-palm; 1.3 Mha pulpwood). Approximately 7.0 Mha of the total plantation area in 2015 (9.2 Mha) were old-growth forest in 1973, of which 4.5-4.8 Mha (24-26% of Borneo-wide deforestation) were planted within five years of forest clearance (3.7-3.9 Mha oil-palm; 0.8-0.9 Mha pulpwood). This rapid within-five-year conversion has been greater in Malaysia than in Indonesia (57-60% versus 15-16%). In Indonesia, a higher proportion of oil-palm plantations was developed on already cleared degraded lands (a legacy of recurrent forest fires). However, rapid conversion of Indonesian forests to industrial plantations has increased steeply since 2005. We conclude that plantation industries have been the principle driver of deforestation in Malaysian Borneo over the last four decades. In contrast, their role in deforestation in Indonesian Borneo was less marked, but has been growing recently. We note caveats in interpreting these results and highlight the need for greater accountability in plantation development.

  2. Response in water yield to the thinning of Pinus radiata, Pinus patula and Eucalyptus grandis plantations

    CSIR Research Space (South Africa)

    Lesch, W

    1997-12-15

    Full Text Available of modem planta- tion silviculture. They involve the marking, felling and removal of a proportion of the trees in the stand. Thinnings are usually applied to redistribute the growth potential of the plantation so that timber yields.... The eucalyptus plantation at Westfalia D is an- other example of how the development of a planta- tion may dominate the observed streamflow, mask- ing the effects of thinnings. The reduction in stream- flow commenced three years...

  3. Cannabis cultivation in Spain: A profile of plantations, growers and production systems.

    Science.gov (United States)

    Alvarez, Arturo; Gamella, Juan F; Parra, Iván

    2016-11-01

    The European market for cannabis derivatives is being transformed. The cultivation of cannabis within the EU and the shift of demand from hashish to domestic marihuana are key aspects of this transformation. Spain, formerly central to the trade of Moroccan hashish, is becoming a marihuana-producing country. The emergence of "import-substitution" has been researched in other EU countries, but thus far the Spanish case remains undocumented. This paper is based on analysis of data of 748 cannabis plantations seized by Spanish police in 2013. The sample comprises reports of seizures identified through a survey of online news and police reports. "Event-analysis" methods were applied to these sources. The analysis offers a typology of plantations, a profile of participants and the different production systems, and a model of regional distribution. Half of the plantations were small (less than 42 plants) and half contained between 100 and 1000 plants, with an average size of 261 plants. About three-quarters of plants were cultivated indoors using stolen electricity. 86% of all plants seized were from large-scale plantations (more than 220 plants). Most plantations were located along the Mediterranean coast, where population and tourism are concentrated. Over three-quarters of those indicted by police were Spanish (85%). Among the foreign owners of big plantations, Dutch nationals predominated. The number of seized plants by province was directly associated with the number of grow shops (β=0.962, pcannabis plantations in the Spanish Mediterranean coast is increasingly replacing import of Moroccan hashish. Indoor cultivation supported by grow shops, that provide the technology and know-how, seem to be the dominant form of organization in this emerging industry. Large-scale plantations may have met most of the demand for marihuana in 2013. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Response of ecosystem carbon fluxes to drought events in a poplar plantation in Northern China

    Science.gov (United States)

    Jie Zhou; Zhiqiang Zhang; Ge Sun; Xianrui Fang; Tonggang Zha; Steve McNulty; Jiquan Chen; Ying Jin; Asko Noormets

    2013-01-01

    Poplar plantations are widely used for timber production and ecological restoration in northern China,a region that experiences frequent droughts and water scarcity. An open-path eddy-covariance (EC)system was used to continuously measure the carbon,water,and energy fluxes in a poplar plantation during the growing season (i.e., April–October)over the period 2006–2008...

  5. Characteristics of Soil Fauna Communities and Habitat in Small-Holder Cocoa Plantation in South Konawe

    OpenAIRE

    Laode Muhammad Harjoni Kilowasid; Tati Suryati Syamsudin; Franciscus Xaverius Susilo; Endah Sulistyawati; Hasbullah Syaf

    2013-01-01

    The composition of soil fauna community have played an important role in regulating decomposition and nutrient cycling in agro-ecosystems (include cocoa plantation). Changes in food availability and conditions in the soil habitat can affect the abundance and diversity of soil fauna. This study aimed: (i) to analyze the pattern of changes in soil fauna community composition and characteristic of soil habitat based on the increasing age of cocoa plantation, and (ii) to identify taxa of soil fau...

  6. Sediment Enrichment Ratio and Nutrient Leached by Runoff and Soil Erosion on Cacao Plantation

    OpenAIRE

    Oteng Haridjaja

    2012-01-01

    Soil consevation management system is an activity for diminishing sediment enrichment ratio and nutrient leachedsby water run off and soil erosion processes. The research was aimed to study sediment enrichment ratio and nutrientleached by run off and soil erosion on cacao plantations. Arachis pintoi with strips parallel contour and multiplestrip cropping of upland rice or soybean (Glycine max) were planted to improve soil physical characterictic oncacao plantation as a main plant. The exprime...

  7. Status of Floor Vegetation under Some Monoculture and Mixculture Plantations in North India

    OpenAIRE

    Ravinder Kumar, Kohli; Harminder Pal, Singh; Daizy, Rani; Department of Botany, Panjab University

    1996-01-01

    A study conducted to assess the floor vegetation shows the presence of 17 species under Populus deltoides in comparison to 28, 29 and 35 under Albizia lebbeck, Dalbergia sissoo and mix-culture plantations, respectively. Further, the biomass and density of floor vegetation is considerably reduced under P. deltoides compared to other plantations. In addition, the indices for species richness, evenness, dominance and diversity are also reduced under P. deltoides showing some inhibitory mechanism...

  8. The relationship between immigration and labour market performance in Sabah’s oil palm plantation sector

    OpenAIRE

    Kasim Mansur

    2016-01-01

    The main objective of this paper is to analyze the relationship between immigration and labor market performance in Sabah region's oil palm plantation industry. The labour market performance refers to the wages and employment of local workers in the oil palm plantation sector. The relationship of these variables can be in short run or/ and in the long run. This study uses Vector Error Correction Model (VECM) to examine the relationship between the immigration and labour market performance. In...

  9. 200 Facteurs de contrôle de la diversité des plantations d ...

    African Journals Online (AJOL)

    AZIZ

    en espèces contribuent à une augmentation sensible de près de 54 % du cortège floristique de la ville, la largeur des rues et .... L'indice de diversité de Shannon calculé pour l'ensemble des plantations est de 2,01 ± 0,85 ... Toutefois, on note une variation sensible de ces valeurs entre plantations et en fonction des niveaux ...

  10. Soil Carbon Stocks Decrease following Conversion of Secondary Forests to Rubber (Hevea brasiliensis) Plantations

    Science.gov (United States)

    de Blécourt, Marleen; Brumme, Rainer; Xu, Jianchu; Corre, Marife D.; Veldkamp, Edzo

    2013-01-01

    Forest-to-rubber plantation conversion is an important land-use change in the tropical region, for which the impacts on soil carbon stocks have hardly been studied. In montane mainland southeast Asia, monoculture rubber plantations cover 1.5 million ha and the conversion from secondary forests to rubber plantations is predicted to cause a fourfold expansion by 2050. Our study, conducted in southern Yunnan province, China, aimed to quantify the changes in soil carbon stocks following the conversion from secondary forests to rubber plantations. We sampled 11 rubber plantations ranging in age from 5 to 46 years and seven secondary forest plots using a space-for-time substitution approach. We found that forest-to-rubber plantation conversion resulted in losses of soil carbon stocks by an average of 37.4±4.7 (SE) Mg C ha−1 in the entire 1.2-m depth over a time period of 46 years, which was equal to 19.3±2.7% of the initial soil carbon stocks in the secondary forests. This decline in soil carbon stocks was much larger than differences between published aboveground carbon stocks of rubber plantations and secondary forests, which range from a loss of 18 Mg C ha−1 to an increase of 8 Mg C ha−1. In the topsoil, carbon stocks declined exponentially with years since deforestation and reached a steady state at around 20 years. Although the IPCC tier 1 method assumes that soil carbon changes from forest-to-rubber plantation conversions are zero, our findings show that they need to be included to avoid errors in estimating overall ecosystem carbon fluxes. PMID:23894456

  11. Soil carbon stocks decrease following conversion of secondary forests to rubber (Hevea brasiliensis) plantations.

    Science.gov (United States)

    de Blécourt, Marleen; Brumme, Rainer; Xu, Jianchu; Corre, Marife D; Veldkamp, Edzo

    2013-01-01

    Forest-to-rubber plantation conversion is an important land-use change in the tropical region, for which the impacts on soil carbon stocks have hardly been studied. In montane mainland southeast Asia, monoculture rubber plantations cover 1.5 million ha and the conversion from secondary forests to rubber plantations is predicted to cause a fourfold expansion by 2050. Our study, conducted in southern Yunnan province, China, aimed to quantify the changes in soil carbon stocks following the conversion from secondary forests to rubber plantations. We sampled 11 rubber plantations ranging in age from 5 to 46 years and seven secondary forest plots using a space-for-time substitution approach. We found that forest-to-rubber plantation conversion resulted in losses of soil carbon stocks by an average of 37.4±4.7 (SE) Mg C ha(-1) in the entire 1.2-m depth over a time period of 46 years, which was equal to 19.3±2.7% of the initial soil carbon stocks in the secondary forests. This decline in soil carbon stocks was much larger than differences between published aboveground carbon stocks of rubber plantations and secondary forests, which range from a loss of 18 Mg C ha(-1) to an increase of 8 Mg C ha(-1). In the topsoil, carbon stocks declined exponentially with years since deforestation and reached a steady state at around 20 years. Although the IPCC tier 1 method assumes that soil carbon changes from forest-to-rubber plantation conversions are zero, our findings show that they need to be included to avoid errors in estimating overall ecosystem carbon fluxes.

  12. Simulation of design-unbiased point-to-particle sampling compared to alternatives on plantation rows

    Science.gov (United States)

    Thomas B. Lynch; David Hamlin; Mark J. Ducey

    2016-01-01

    Total quantities of tree attributes can be estimated in plantations by sampling on plantation rows using several methods. At random sample points on a row, either fixed row lengths or variable row lengths with a fixed number of sample trees can be assessed. Ratio of means or mean of ratios estimators can be developed for the fixed number of trees option but are not...

  13. An Empirical Assessment of Transgene Flow from a Bt Transgenic Poplar Plantation.

    Directory of Open Access Journals (Sweden)

    Jianjun Hu

    Full Text Available To assess the possible impact of transgenic poplar plantations on the ecosystem, we analyzed the frequency and distance of gene flow from a mature male transgenic Populus nigra plantation carrying the Bacillus thuringiensis toxin gene (Bt poplar and the survival of Bt poplar seeds. The resultant Bt poplar seeds occurred at a frequency of ~0.15% at 0 m to ~0.02% at 500 m from the Bt poplar plantation. The germination of Bt poplar seeds diminished within three weeks in the field (germination rate from 68% to 0% compared to 48% after three weeks of storage at 4°C. The survival rate of seedlings in the field was 0% without any treatment but increased to 1.7% under the addition of four treatments (cleaning and trimming, watering, weeding, and covering with plastic film to maintain moisture after being seeded in the field for eight weeks. The results of this study indicate that gene flow originating from the Bt poplar plantation occurred at an extremely low level through pollen or seeds under natural conditions. This study provides first-hand field data on the extent of transgene flow in poplar plantations and offers guidance for the risk assessment of transgenic poplar plantations.

  14. Differential Performance between Two Timber Species in Forest Logging Gaps and in Plantations in Central Africa

    Directory of Open Access Journals (Sweden)

    Adeline Fayolle

    2015-02-01

    Full Text Available To develop silvicultural guidelines for high-value timber species of Central African moist forests, we assessed the performance of the pioneer Milicia excelsa (iroko, Moraceae, and of the non-pioneer light demander Pericopsis elata (assamela, Fabaceae in logging gaps and in plantations in highly degraded areas in south-eastern Cameroon. The survival and size of each seedling was regularly monitored in the silvicultural experiments. Differences in performance and allometry were tested between species in logging gaps and in plantations. The two species performance in logging gaps was significantly different from plantations and concurred with the expectations of the performance trade-off hypothesis but not with the expectations of species light requirements. The pioneer M. excelsa survived significantly better in logging gaps while the non-pioneer P. elata grew significantly faster in plantations. The high mortality and slow growth of M. excelsa in plantations is surprising for a pioneer species but could be explained by herbivory (attacks from a gall-making psyllid. Identifying high-value native timber species (i with good performance in plantations such as P. elata is of importance to restore degraded areas; and (ii with good performance in logging gaps such as M. excelsa is of importance to maintain timber resources and biodiversity in production forests.

  15. Evaluation of Soil Physical and Chemical Properties in Poplar Plantations in North of Iran

    Directory of Open Access Journals (Sweden)

    Ali Salehi

    2012-12-01

    Full Text Available Soil physical and chemical properties and some quantitative characteristics of Populus deltoides Marsh (clone 79.51 plantations and relationships between them were evaluated in Guilan plain of north of Iran. Two same aged poplar plantations with low and high qualities were selected. In each poplar plantation, fifteen sample plots with systematic sampling method were selected. In each sample plot diameter at breast height (DBH as well as height of all trees within them was determined. Soil samples were taken from 0-20cm in each plot and soil texture, water holding capacity (WHC, bulk density (B.D and particle density (P.D as well as soil porosity, O.C, N, available P and exchangeable K were determined for each soil sample in laboratory. Tree data and soil properties between two plantations were analysed using independent samples t-test (Student’s t test at p < 0.05. The results showed that among soil physical properties, percentage of clay, sand, B.D and WHC and amongst soil chemical properties O.C, N, available P and exchangeable K were significantly different between two plantations. Heavy textured soils with high B.D are undesirable for growing of populus deltoides in study area. The results also indicated that poor quality plantations has negative effect on soil nutrient and reduces its fertility. Reduction of nutrient availability had negative effects on quantity and quality of poplar trees.

  16. System analysis of a bio-energy plantation: full greenhouse gas balance and energy accounting (POPFULL)

    Science.gov (United States)

    Ceulemans, R.; Janssens, I.; Berhongaray, G.; Broeckx, L.; De Groote, T.; ElKasmioui, O.; Fichot, R.; Njakou Djomo, S.; Verlinden, M.; Zona, D.

    2011-12-01

    In recent year the environmental impact of fossil fuels and their reduced availability are leading to an increasing interest in renewable energy sources, among them bio-energy. However, the cost/benefit in establishing, managing, and using these plantations for energy production should be quantified together with their environmental impact. In this project we are performing a full life cycle analysis (LCA) balance of the most important greenhouse gases (CO2, CH4, N2O, H2O and O3), together with full energy accounting of a short-rotation coppice (SRC) plantation with fast-growing trees. We established the plantation two years ago and we have been monitoring net fluxes of CO2, N2O, CH4, and O3, in combination with biomass pools (incl. soil) and fluxes, and volatile organic carbon (VOCs). This poplar plantation will be monitored for another two years then harvested and transformed into bio-energy. For the energy accounting we are performing a life cycle analysis and energy efficiency assessments over the entire cycle of the plantation until the production of electricity and heat. Here we present an overview of the results from the first two years from the plantation establishment, and some of the projections based on these first results.

  17. Ash, Asterionella, and Anglers: A Paleolimnological Approach to Understanding Anthropogenic and Volcanogenic Disturbances in a Small Sub-Alpine Watershed

    Science.gov (United States)

    Howard, K. L.; Noble, P. J.

    2014-12-01

    This poster summarizes geochemical, biological, hydrological, and watershed data that characterize Manzanita Lake, a small sub-alpine catchment in Lassen Volcanic National Park, CA. The future objective is to use characteristics of this system to interpret variations in diatom and sediment composition dating back to the 1914 Mt. Lassen eruption from a recently recovered lake core. Manzanita Lake is a small (0.18 km2) lake with a ~30 km2 watershed area situated on the northwest flank of Mt. Lassen, one of the most active Cascade volcanoes, and is a valuable recreational spot for anglers and visitors. Hydraulic residence time is short; roughly 119 days, and is derived from lake volume (1.0 X 106m3) and estimates of stream inflow (~6 ft3/sec) and outflow (~3 ft3/sec) that were made from May 2014 sampling data. Limnological sampling in 2012-2014 suggests that Manzanita Lake exhibits stable thermal stratification in the summer months, which is unusual given the shallow depth (~10m), but possibly supported by the morphometry of the lake basin and inputs of cold snowmelt from the flank of Lassen Peak. The lake is a moderately conductive (100-114 μS), mesotrophic system with secchi depths ranging from 8m to the bottom (~10m). Total phosphorus (TP) ranges from 15-25 ppb and dissolved inorganic nitrogen (DIN) from 2-15 ppb, with ammonium in the epilimnion being the largest contributor. A high concentration of silica (Si) in surface water inputs (34 mg/L) to Manzanita Lake likely reflects the rhyodacitic bedrock geology and large drainage ratio (164) of the watershed. Variations in Si concentration in the lake seem to be coupled with diatom production. During the sampling period Manzanita Lake is has been dominated by diatom blooms throughout the summer and fall months. There is a seasonal succession in the diatom species present, with abundant Asterionella formosa in the spring, transitioning to abundant Fragilaria crotonensis in the summer months, to a mixed dominance of

  18. Spatio-seasonal variability in dissolved organic matter optical properties and its bioavailability in a subalpine lake

    Science.gov (United States)

    Stadler, Masumi; Ejarque, Elisabet; Kainz, Martin J.

    2017-04-01

    Allochthonous and autochothonous dissolved organic matter (DOM) in lakes mainly originate from terrestrial and aquatic primary production, respectively. Due to their differing biochemical composition the degradability of DOM by microorganisms is expected to vary. The carbon use efficiency of bacteria and DOM biodegradability determine whether the consumed DOM is incorporated into microbial biomass or respired to CO2 and ultimately emitted into the atmosphere. Thus, understanding the interaction of biodegradable DOM and its consumers is crucial to increase our knowledge on the role of lakes in the global carbon cycling. However, interactions of specific aquatic DOM signatures and the microbial population still remain widely debated. The aim of this study was to explore how DOM biodegradability changes along a stream-lake continuum at different seasons of the year. We monitored DOM quantity and its optical properties, inorganic nutrients, CO2 and bacterial growth over 20 days in dark bioassays with water from the inflow, outflow and at three layers of an oligotrophic subalpine lake. Preliminary results reveal highest microbial abundance in the metalimnion in winter and summer (0.7 106 and 2.5 106 cells mL-1, respectively) and the inflow in spring and autumn (1 106 and 1.4 106 cells mL-1, respectively) after 20 days. Surprisingly, with the exception of winter samples final inflow bacterial abundance results high, despite its lowest initial natural cell concentration, providing evidence for effective utilisation of terrestrial DOM, even with its high humic signature as indicated by the humification index (HIX). Nonetheless, after a microbial biomass peak with the inflow yielding mostly highest after three days, at the final experimental stage microbial biomass does only marginally differ between all sites with the exception of autumn samples where outflow and metalimnion turn out most productive. Even though the DOM of all lake sites and the lake outflow were

  19. Drought induced changes of plant belowground carbon allocation affect soil microbial community function in a subalpine meadow

    Science.gov (United States)

    Fuchslueger, L.; Bahn, M.; Fritz, K.; Hasibeder, R.; Richter, A.

    2012-12-01

    There is growing evidence that climate extremes may affect ecosystem carbon dynamics more strongly than gradual changes in temperatures or precipitation. Climate projections suggest more frequent heat waves accompanied by extreme drought periods in many parts of Europe, including the Alps. Drought is considered to decrease plant C uptake and turnover, which may in turn decrease belowground C allocation and potentially has significant consequences for microbial community composition and functioning. However, information on effects of drought on C dynamics at the plant-soil interface in real ecosystems is still scarce. Our study aimed at understanding how summer drought affects soil microbial community composition and the uptake of recently assimilated plant C by different microbial groups in grassland. We hypothesized that under drought 1) the microbial community shifts, fungi being less affected than bacteria, 2) plants decrease belowground C allocation, which further reduces C transfer to soil microbes and 3) the combined effects of belowground C allocation, reduced soil C transport due to reduced soil moisture and shift in microbial communities cause an accumulation of extractable organic C in the soil. Our study was conducted as part of a rain-exclusion experiment in a subalpine meadow in the Austrian Central Alps. After eight weeks of rain exclusion we pulse labelled drought and control plots with 13CO2 and traced C in plant biomass, extractable organic C (EOC) and soil microbial communities using phospholipid fatty acids (PLFA). Drought induced a shift of the microbial community composition: gram-positive bacteria became more dominant, whereas gram-negative bacteria were not affected by drought. Also the relative abundance of fungal biomass was not affected by drought. While total microbial biomass (as estimated by total microbial PLFA content) increased during drought, less 13C was taken up. This reduction was pronounced for bacterial biomarkers. It reflects

  20. Soil attributes and microclimate are important drivers of initial deadwood decay in sub-alpine Norway spruce forests.

    Science.gov (United States)

    Fravolini, Giulia; Egli, Markus; Derungs, Curdin; Cherubini, Paolo; Ascher-Jenull, Judith; Gómez-Brandón, María; Bardelli, Tommaso; Tognetti, Roberto; Lombardi, Fabio; Marchetti, Marco

    2016-11-01

    Deadwood is known to significantly contribute to global terrestrial carbon stocks and carbon cycling, but its decay dynamics are still not thoroughly understood. Although the chemistry of deadwood has been studied as a function of decay stage in temperate to subalpine environments, it has generally not been related to time. We therefore studied the decay (mass of deadwood, cellulose and lignin) of equal-sized blocks of Picea abies wood in soil-mesocosms over two years in the Italian Alps. The 8 sites selected were along an altitudinal sequence, reflecting different climate zones. In addition, the effect of exposure (north- and south-facing slopes) was taken into account. The decay dynamics of the mass of deadwood, cellulose and lignin were related to soil parameters (pH, soil texture, moisture, temperature) and climatic data. The decay rate constants of Picea abies deadwood were low (on average between 0.039 and 0.040y(-1)) and of lignin close to zero (or not detectable), while cellulose reacted much faster with average decay rate constants between 0.110 and 0.117y(-1). Our field experiments showed that local scale factors, such as soil parameters and topographic properties, influenced the decay process: higher soil moisture and clay content along with a lower pH seemed to accelerate wood decay. Interestingly, air temperature negatively correlated with decay rates or positively with the amount of wood components on south-facing sites. It exerted its influence rather on moisture availability, i.e. the lower the temperature the higher the moisture availability. Topographic features were also relevant with generally slower decay processes on south-facing sites than on north-facing sites owing to the drier conditions, the higher pH and the lower weathering state of the soils (less clay minerals). This study highlights the importance of a multifactorial consideration of edaphic parameters to unravel the complex dynamics of initial wood decay. Copyright © 2016 Elsevier

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

    Science.gov (United States)

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

    1994-01-01

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

  2. Extraction of oil palm plantations on the undulating terrains in the Borneo using PALSAR Global Mosaic

    Science.gov (United States)

    Tanigaki, Y.; Ishii, R.; Kobayashi, H.; Nagai, S.; Suzuki, R.

    2013-12-01

    Conversions of forests and peat swamps into oil palm plantations might cause decrease of net ecosystem production, change of water stream and loss of biodiversity. Most of the oil plantations in the South East Asia have been expanded in the past decade. For monitoring the distribution and condition of these plantations, the PALSAR Global Mosaic data set (PGM) have been utilized. This PGM is one of the L-Band Synthetic Aparture Radar (SAR) data sets orthorectified and mosaicked (unified). Unlike optical satellite imagery, the L-band SAR is useful especially for cloudy tropic regions. In addition, PGM have high resolution (about 10 m) and contains cross polarization (HV) SAR data which is useful for observation of forest because cross polarization SAR data contain data of the volume scattering which reflect the volume of plant bodies. On the other hand, topographic effect in PGM is not reduced sufficiently because of low resolution of DEM utilized to make PGM. As a result, pixel value of PGM is affected by the highlight effect especially in undulating terrains. These undulating terrains consist of rises which have about 10m height, exist in about 100m horizontal interval and cause striped patterns on SAR images. These patterns result in difficulty in extracting oil palm plantation using SAR imagery in the undulating terrains. However, many papers extracting oil palm plantations didn't show the accuracy of distributions extracted as oil palm plantation in the undulating terrains and thus it isn't clear how well oil palm plantations on the undulating terrains can be extracted. In this study, we carried out a supervised classification and extracted oil palm plantations in the north-west of Borneo Island. The Island is a part of the South East Asia and contains undulating terrains. In this extraction, we used the PGM data, a learning model and the training data made from PGM data, aerial photograph, high resolution optical satellite data and field survey data. After

  3. Long-term (13 Years) decomposition rates of forest floor organic matter on paired coniferous and deciduous watersheds with contrasting temperature regimes

    Science.gov (United States)

    Robert G. Qualls

    2016-01-01

    Two sets of paired watersheds on north and South facing slopes were utilized to simulate the effects of temperature differences that are on the scale of those expected with near-term climatic warming on decomposition. Two watersheds were pine plantations (Pinus strobus L.) and two were mature deciduous forests established at similar elevation...

  4. Development of an aerial counting system in oil palm plantations

    Science.gov (United States)

    Zulyma Miserque Castillo, Jhany; Laverde Diaz, Rubbermaid; Rueda Guzmán, Claudia Leonor

    2016-07-01

    This paper proposes the development of a counting aerial system capable of capturing, process and analyzing images of an oil palm plantation to register the number of cultivated palms. It begins with a study of the available UAV technologies to define the most appropriate model according to the project needs. As result, a DJI Phantom 2 Vision+ is used to capture pictures that are processed by a photogrammetry software to create orthomosaics from the areas of interest, which are handled by the developed software to calculate the number of palms contained in them. The implemented algorithm uses a sliding window technique in image pyramids to generate candidate windows, an LBP descriptor to model the texture of the picture, a logistic regression model to classify the windows and a non-maximum suppression algorithm to refine the decision. The system was tested in different images than the ones used for training and for establishing the set point. As result, the system showed a 95.34% detection rate with a 97.83% precision in mature palms and a 79.26% detection rate with a 97.53% precision in young palms giving an FI score of 0.97 for mature palms and 0.87 for the small ones. The results are satisfactory getting the census and high-quality images from which is possible to get more information from the area of interest. All this, achieved through a low-cost system capable of work even in cloudy conditions.

  5. Dissipation of the fungicide hexaconazole in oil palm plantation.

    Science.gov (United States)

    Maznah, Zainol; Halimah, Muhamad; Ismail, Sahid; Idris, Abu Seman

    2015-12-01

    Hexaconazole is a potential fungicide to be used in the oil palm plantation for controlling the basal stem root (BSR) disease caused by Ganoderma boninense. Therefore, the dissipation rate of hexaconazole in an oil palm agroecosystem under field conditions was studied. Two experimental plots were treated with hexaconazole at the recommended dosage of 4.5 g a.i. palm(-1) (active ingredient) and at double the recommended dosage (9.0 g a.i. palm(-1)), whilst one plot was untreated as control. The residue of hexaconazole was detected in soil samples in the range of 2.74 to 0.78 and 7.13 to 1.66 mg kg(-1) at the recommended and double recommended dosage plots, respectively. An initial relatively rapid dissipation rate of hexaconazole residues occurred but reduced with time. The dissipation of hexaconazole in soil was described using first-order kinetics with the value of coefficient regression (r (2) > 0.8). The results indicated that hexaconazole has moderate persistence in the soil and the half-life was found to be 69.3 and 86.6 days in the recommended and double recommended dosage plot, respectively. The results obtained highlight that downward movement of hexaconazole was led by preferential flow as shown in image analysis. It can be concluded that varying soil conditions, environmental factors, and pesticide chemical properties of hexaconazole has a significant impact on dissipation of hexaconazole in soil under humid conditions.

  6. SOCIAL EXCLUSION: GUATEMALAN YOUTH WITHIN COFFEE PLANTATIONS AT SOCONUSCO CHIAPAS

    Directory of Open Access Journals (Sweden)

    Laura Itzel Ramírez-Ramos

    2014-07-01

    Full Text Available Mexico's southern border is the entry point for different migratory flows, mainly from Central America, these flows have taken place under socioeconomic contexts and conditions which demand the constant livelihood strategies pursuit from people. This paper is focused on the agricultural laborers from Guatemalan origin, within coffee plantation farms at the Soconusco, Chiapas. The main objective is arguing how the lack of access -or restricted access- to education and the precarious inclusion to work and migration, have positioned youth population of migrant laborers, from Guatemalan origin, into social processes of social exclusion and vulnerability. It is concluded that conditions generated from these processes, preclude the generation of different work expectations, the access to a higher quality of life and the social mobility in a men and woman development crucial stage. The exposed information comes from quantitative and qualitative research methods. A nonrandom survey was applied to 129 families; 20 semi-structured interviews for children and adolescents within farms and 25 to actors involved in the recognition and performance of the human rights of migrant children in the southern Mexican border area.

  7. Advances in pollination ecology from tropical plantation crops.

    Science.gov (United States)

    Klein, Alexandra-Maria; Cunningham, Saul A; Bos, Merijn; Steffan-Dewenter, Ingolf

    2008-04-01

    Although ecologists traditionally focus on natural ecosystems, there is growing awareness that mixed landscapes of managed and unmanaged systems provide a research environment for understanding basic ecological relationships on a large scale. Here, we show how tropical agroforestry systems can be used to develop ideas about the mechanisms that influence species diversity and subsequent biotic interactions at different spatial scales. Our focus is on tropical plantation crops, mainly coffee and cacao, and their pollinators, which are of basic ecological interest as partners in an important mutualistic interaction. We review how insect-mediated pollination services depend on local agroforest and natural habitats in surrounding landscapes. Further, we evaluate the functional significance of pollinator diversity and the explanatory value of species traits, and we provide an intercontinental comparison of pollinator assemblages. We found that optimal pollination success might be best understood as a consequence of niche complementarities among pollinators in landscapes harboring various species. We further show that small cavity-nesting bees and small generalist beetles were especially affected by isolation from forest and that larger-bodied insects in the same landscapes were not similarly affected. We suggest that mixed tropical landscapes with agroforestry systems have great potential for future research on the interactions between plants and pollinators.

  8. FROM UAS DATA ACQUISITION TO ACTIONABLE INFORMATION – HOW AN END-TO-END SOLUTION HELPS OIL PALM PLANTATION OPERATORS TO PERFORM A MORE SUSTAINABLE PLANTATION MANAGEMENT

    Directory of Open Access Journals (Sweden)

    C. Hoffmann

    2016-06-01

    Full Text Available Palm oil represents the most efficient oilseed crop in the world but the production of palm oil involves plantation operations in one of the most fragile environments - the tropical lowlands. Deforestation, the drying-out of swampy lowlands and chemical fertilizers lead to environmental problems that are putting pressure on this industry. Unmanned aircraft systems (UAS together with latest photogrammetric processing and image analysis capabilities represent an emerging technology that was identified to be suitable to optimize oil palm plantation operations. This paper focuses on two key elements of a UAS-based oil palm monitoring system. The first is the accuracy of the acquired data that is necessary to achieve meaningful results in later analysis steps. High performance GNSS technology was utilized to achieve those accuracies while decreasing the demand for cost-intensive GCP measurements. The second key topic is the analysis of the resulting data in order to optimize plantation operations. By automatically extracting information on a block level as well as on a single-tree level, operators can utilize the developed application to increase their productivity. The research results describe how operators can successfully make use of a UAS-based solution together with the developed software solution to improve their efficiency in oil palm plantation management.

  9. PROBLEMATIC IN THE PROCESSES OF PRODUCTION IN RUBBER PLANTATIONS (Hevea brasiliensis Muell Arg. IN TABASCO, MEXICO

    Directory of Open Access Journals (Sweden)

    Heyra Izquierdo-Bautista

    2011-03-01

    Full Text Available The objective of this study was to identify some of the basic problems presented in the production process in rubber plantations Hevea brasiliensis Muell Arg. in Tabasco, Mexico. The applied diagnosis technique was the randomized survey for 68 producers in plantations under rubber production. ANOVA and Duncan analyses were done (P< 0.05. Plantations under production were between 7 to 46 years old. The 24% of these are considered as young plantations (7 to 18 years old, 34% mature (19 to 30 years old, and 12% old growth (31 to 46 years old, according to the level of latex production. Latex collection is realized by 85% men and 15% women. An important detected problem is the incidence of insects and diseases over the 82% of the plantations. In Tabasco State, two types of raw material are generated: clot (solid and latex (liquid. The tapping systems are ½ S d/1 6d/7 (one cuts in an average spiral with daily tapping over the 49% of the plantations, and the system ½ S d/2 6d/7, cuts in semi-spirals with alternating tapping over 51% of the plantations. The producers that practiced daily tapped obtained yields of 1.588 kg per ha/yr of dry rubber, in the other hand, those that tapped every other day obtained a yield of 1.647 kg per ha/year of dry rubber. The yield in daily tapping was 3.54% lower than the system with alternating tapping. The income obtained by the producers of fresh rubber varied from $8.750, 00 (810, 2 USD ha/year to $27.870, 00 (2.580 USD ha/year in 2006 and the production of latex from $5.955, 00 (551, 4 USD to 16.568,00 (1.534 USD per ha/year.

  10. The value of primary, secondary, and plantation forests for a neotropical herpetofauna.

    Science.gov (United States)

    Gardner, Toby A; Ribeiro-Júnior, Marco Antônio; Barlow, Jos; Avila-Pires, Teresa Cristina Sauer; Hoogmoed, Marinus S; Peres, Carlos A

    2007-06-01

    Plantation forests and second-growth forests are becoming dominant components of many tropical forest landscapes. Yet there is little information available concerning the consequences of different forestry options for biodiversity conservation in the tropics. We sampled the leaf-litter herpetofauna of primary, secondary, and Eucalyptus plantation forests in the Jari River area of northeastern Brazilian Amazonia. We used four complementary sampling techniques, combined samples from 2 consecutive years, and collected 1739 leaf-litter amphibians (23 species) and 1937 lizards (30 species). We analyzed the data for differences among forest types regarding patterns of alpha and beta diversity, species-abundance distributions, and community structure. Primary rainforest harbored significantly more species, but supported a similar abundance of amphibians and lizards compared with adjacent areas of second-growth forest or plantations. Plantation forests were dominated by wide-ranging habitat generalists. Secondary forest faunas contained a number of species characteristic of primary forest habitat. Amphibian communities in secondary forests and Eucalyptus plantations formed a nested subset of primary forest species, whereas the species composition of the lizard community in plantations was distinct, and was dominated by open-area species. Although plantation forests are relatively impoverished, naturally regenerating forests can help mitigate some negative effects of deforestation for herpetofauna. Nevertheless, secondary forest does not provide a substitute for primary forest, and in the absence of further evidence from older successional stands, we caution against the optimistic claim that natural forest regeneration in abandoned lands will provide refuge for the many species that are currently threatened by deforestation.

  11. Grazing by reindeer in subarctic coniferous forests - how it is affecting three main greenhouse gas emissions from soils.

    Science.gov (United States)

    Köster, Kajar; Köster, Egle; Berninger, Frank; Pumpanen, Jukka

    2017-04-01

    Reindeer (Rangifer tarandus L.) are the most important large mammalian herbivores in the northern ecosystems, strongly affecting Arctic lichen dominated ecosystems. Changes caused by reindeer in vegetation have indirect effects on physical features of the soil e.g. soil microclimate, root biomass and also on soil carbon dynamics, and little is known about reindeer and their impact on greenhouse gas (GHG) emissions between the soil and atmosphere. In a field experiment in northern boreal subarctic coniferous forests in Finnish Lapland, we investigated the influence of reindeer grazing on soil GHG (CO2, CH4 and N2O) fluxes, ground vegetation coverage and biomass, soil temperature and water content. The study was carried out in the growing season of the year 2014. We established the experiment as a split plot experiment with 2 blocks and 5 sub-plots per treatment that were divided into grazed and non-grazed parts, separated with a fence. The sample plots are located along the borderline between Finland and Russia, where the non-grazed area was excluded from reindeer already in 1918, to prevent the Finnish reindeer from going to the Russian side and there are not many reindeer on Russian side of the area. Our study showed that grazing by reindeer significantly affected lichen and moss biomasses. Lichen biomass was significantly lower in the grazed. We also observed that when lichens were removed, mosses were quickly overtaking the areas and moss biomass was significantly higher in grazed areas compared to non-grazed areas. Our results indicated that grazing by reindeer in the northern boreal subarctic forests affects the GHG emissions from the forest floor and these emissions largely depend on changes in vegetation composition. Soil was always a source of CO2in our study, and soil CO2 emissions were significantly smaller in non-grazed areas compared to grazed areas. The soils in our study areas were CH4 sinks through entire measurement period, and grazed areas consumed

  12. Effects of air pollution and simulated acid rain on the ground vegetation of coniferous forests; Wirkungen von Luftverunreinigung und kuenstlichem sauren Regen auf die Bodenvegetation in Koniferenwaeldern

    Energy Technology Data Exchange (ETDEWEB)

    Rodenkirchen, H. [Lehrstuhl fuer Bodenkunde und Standortslehre, Ludwig-Maximilians-Univ. Muenchen (Germany)

    1993-04-01

    Descriptive and experimental studies on the ground vegetation of coniferous forests in Bavaria indicated the following phenomena: a. In N-limited pine forests recent eutrophication effects occur. b. The structure of the moss layer in coniferous forests sensitively reacts to very acid throughfall water (pH < 3.2). c. Oxalis acetosella is a forest herb with a relatively high Ca-demand for optimum growth and is thusly sensitive to distinct acid-caused Ca-losses in the top soil, or inhibition of Ca-uptake. (orig.) [Deutsch] Deskriptive und experimentelle Studien an der Bodenvegetation bayerischer Nadelwaelder wiesen auf folgende Phaenomene hin: a. In N-limitierten Kiefernforsten treten rezente Eutrophierungswirkungen auf. b. Die Struktur der Moosschicht in Koniferenbestaenden reagiert empfindlich auf starke Aziditaet (pH < 3,2) des Kronentraufwassers. c. Oxalis acetosella ist eine Waldpflanze mit relativ hohem Ca-Bedarf fuer optimales Gedeihen; sie reagiert daher empfindlich auf staerkere depositionsbedingte Ca-Verluste aus dem Oberboden oder eine Hemmung der Ca-Aufnahme. (orig.)

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

    Science.gov (United States)

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

    2016-08-01

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

  14. [Nutrient accumulation and cycling in pure and mixed plantations of Azadirachta indica and Acacia auriculiformis in a dry-hot valley, Yunnan Province, southwest China].

    Science.gov (United States)

    Gao, Cheng-Jie; Li, Kun; Tang, Guo-Yong; Zhang, Chun-Hua; Li, Bin

    2014-07-01

    To ease the implementation of effective nutrient management for plantations with different vegetation restoration patterns and to assist in the selection of appropriate species and forestation patterns, nutrient (N, P, K, Ca and Mg) accumulation and cycling were investigated and compared in three plantations (10-year-old Azadirachta indica, Acacia auriculiformis and mixed A. indica--A. auriculiformis plantations) in Yuanmou Valley, a dry-hot valley of Yunnan Province, Southwestern China. The result showed that total nutrient accumulations were 333.05, 725.61 and 533.85 kg x hm(-2) in pure plantations of A. indica and A. auriculiformis, and in A. indica--A. auriculiformis mixed plantation, respectively. The nutrient accumulation of various organs was ranked as branches > stems > roots > leaves > bark in the A. indica plantation and branches > stems > leaves > roots > bark both in the A. auriculiformis plantation and in the mixed plantation. Changes in accumulation of various nutrients in the mixed plantation were similar to that in the A. auriculiformis plantation (Ca > N > K > Mg > P), which were different from the A. indica plantation (Ca > K > N > Mg > P). Annual net nutrient accumulation, return and absorption in these plantations ranged from 62.72 to 162.19 kg x hm(-2) x a(-1), 48.82 to 88.86 kg x hm-2 a-1 and 111.54 to 251.05 kg x hm(-2) x a(-1), respectively, which were all the highest in the A. auriculiformis planta- tion, followed by the mixed plantation, and were the lowest in the A. indica plantation. The nutrient utilization coefficient, the cycling coefficient and the recycling period were estimated to be from 0.34 to 0.39, 0.35 to 0.44, and 6.54 to 8.17 a, respectively. The lower nutrient return and circulation rate of N or P in the A. indica plantation showed that this plantation had a poor ability to maintain soil fertility, while the highest nutrient circulation rate of N or P was observed in the A. auriculiformis plantation that displayed the

  15. Energy fluxes in oil palm plantations as affected by water storage in the trunk

    Science.gov (United States)

    Meijide, Ana; Röll, Alexander; Fan, Yuanchao; Herbst, Mathias; Niu, Furong; Tiedemann, Frank; June, Tania; Rauf, Abdul; Hölscher, Dirk; Knohl, Alexander

    2017-04-01

    Oil palm is increasingly expanding, particularly in Indonesia, but information on water and energy fluxes in oil palm plantations is still very limited and on how those are affected by environmental conditions or oil palm age. Using the eddy covariance technique, we studied turbulent fluxes of sensible (H) and latent (LE) heat and gross primary production (GPP) for 8 months each in a young oil palm plantation (1-year old) and subsequently in a mature plantation (12-year old) in Jambi Province, Sumatra, Indonesia. We measured transpiration (T) simultaneously using a sap flux technique. The energy budget was dominated by LE in both plantations, particularly in the mature one, where it represented up to 70% of the available energy. In the young oil palm plantation, evapotranspiration (ET) was significantly reduced and H fluxes were higher. This affected the Bowen ratio, defined as the ratio of H and LE, which was higher in the 1-year old plantation (0.67±0.33), where it remained constant during the day, than in the mature plantation (0.14±0.09), where it varied considerably over the day, suggesting that water accumulated inside the canopy. Using the Community Land Model (CLM), a process based land surface model that has been adapted to oil palm functional traits (i.e. CLM-Palm), we investigated the contribution of different water sources to the measured fluxes. CLM-Palm differentiates leaf and stem surfaces in modelling water interception and is therefore able to diagnose the fraction of dry leaves that contribute to T and the wet fraction of all vegetation surfaces (leaf and stem) that contributes to evaporation. Results from our simulations strengthen our hypothesis of significant contribution of canopy evaporation to ET. As observed in the field, water accumulates inside the canopy in the mature plantation in oil palm trunk surfaces including epiphytes, creating water reservoirs in the trunk, which potentially contribute to ET when they evaporate. The decoupling

  16. Floristic and community diversity of sub-alpine and alpine grasslands and grazed dwarf-shrub heaths in the Romanian Carpathians

    Directory of Open Access Journals (Sweden)

    Coldea, Gheorghe

    1998-12-01

    Full Text Available Floristic diversity at community level and community diversity at landscape level are presented for the main grassland and dwarf-shrub communities in the sub-alpine and alpine zones in five mountain ranges of the Romanian Carpathians. The 30 plant communities studied had their floristic composition and distribution determined by geological substratum and pedo-climatic factors. The most diverse grasslands (Oxytropido-Elynetum, Seslerio haynaldianae-Caricetun were on calcareous substratum and on the mountain slopes (Festucetum pictae, whilst the lowest diversity was in the oligo-mesotrophic sub-alpine grasslands (Scorzonero- Festucetum nigricantis, Alchemillo-Poetum alpinae, Violo-Nardetum. The Shannon-Weaver diversity index for the communities increased almost linearly with the number of species per community, whilst community diversity in the five mountain ranges was a function of the number of communities per mountain range.

    [fr] Nous présentons dans ce travail la diversité floristique au niveau de la communauté et la diversité de communautés au niveau du paysage pour les principaux types de pâturages et de communautés à petits arbustes des étages subalpin et alpin de cinq chaînes montagneuses des Carpathes en Roumanie. Aussi bien la composition floristique que la distribution des 30 communautés étudiées dépendent de la nature géologique du terrain et des facteurs édapho-climatiques. Les pâturages les plus riches en diversité (Oxytropido-Elynetum, Seslerio haynaldianae- Caricetun se développent sur substrat calcaire et sur les versants des montagnes (Testucetum pictae; par contre la plus faible diversité a été rencontrée dans les pâturages oligo-mesotrophes subalpins (Scorzonero-Festucetum nigricantis, Alchemillo-Poetum alpinae, Violo-Nardetum. L'index de diversité de Shannon- Weaver augmente quasi linéairement avec le nombre d'espèces de chaque communauté, tandis que

  17. Responses of assemblages of Orthoptera to management and use of ski slopes on upper sub-alpine meadows in the Austrian Alps.

    Science.gov (United States)

    Illich, Ingeborg P; Haslett, John R

    1994-05-01

    The Orthoptera assemblages occurring on sub-alpine ski slopes were compared with those found on neighbouring unskied meadows by making frequent transect counts at two pairs of sites in the Gastein valley in the Austrian Central Alps. On one of the ski slopes no Orthoptera were present, although two species were abundant on the control meadow a few meters away. On the second ski slope, the Orthoptera assemblage exhibited reduced species richness, lower densities of individuals and a generally accelerated rate of nymphal development compared to the control meadow populations. These results may be explained in terms of the changed habitat conditions on the ski slopes and the known biologies of the species concerned. The implications of the findings for winter tourism management in high altitude ecosystems are briefly discussed.

  18. Can mangrove plantation enhance the functional diversity of macrobenthic community in polluted mangroves?

    Science.gov (United States)

    Leung, Jonathan Y S; Cheung, Napo K M

    2017-03-15

    Mangrove plantation is widely applied to re-establish the plant community in degraded mangroves, but its effectiveness to restore the ecological functions of macrobenthic community remains poorly known, especially when pollution may overwhelm its potential positive effect. Here, we tested the effect of mangrove plantation on the ecological functions of macrobenthic community in a polluted mangrove by analyzing biological traits of macrobenthos and calculating functional diversity. Mangrove plantation was shown to enhance the functional diversity and restore the ecological functions of macrobenthic community, depending on seasonality. Given the polluted sediment, however, typical traits of opportunistic species (e.g. small and short-lived) prevailed in all habitats and sampling times. We conclude that mangrove plantation can help diversify the ecological functions of macrobenthic community, but its effectiveness is likely reduced by pollution. From the management perspective, therefore, pollution sources must be stringently regulated and mangrove plantation should be conducted to fully recover degraded mangroves. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. The legacy of George L. Beckford’s plantation economy thesis in Jamaica

    Directory of Open Access Journals (Sweden)

    Jean Besson

    1995-01-01

    Full Text Available [First paragraph] Plantation Economy, Land Reform and the Peasantry in a Historical Perspective: Jamaica 1838-1980. CLAUS STOLBERG & SWITHIN WILMOT(eds.- Kingston: Friedrich Ebert Stiftung, 1992. 145 pp. (Paper n.p. This interdisciplinary collection focuses on the integration of Jamaica's classical plantation economy with the world economy, and the impact of the plantation economy on the peasantry, land reform, and agrarian modemization in Jamaica from emancipation in 1838 up to 1980. The eight papers comprising the volume were, as a one-page editorial "Introduction" outlines, presented at a symposium at the University of the West Indies, Mona, and are dedicated to the late Professor George Beckford whose work on persistent poverty in plantation economies championed the Jamaican peasantry. As such, the book is a welcome addition to the literature on the Caribbean plantation-peasant interface. However, the chapters are uneven in quality, with some reflecting analytical weaknesses and a lack of historical depth. Typographical errors, grammatical mistakes, and poor documentation are also noticeable. In addition, contrasting perspectives emerge among the contributors and this is not addressed by the editors.

  20. Comparison of butterfly diversity in forested area and oil palm plantation

    Directory of Open Access Journals (Sweden)

    YANTO SANTOSA

    2017-03-01

    Full Text Available Abstrak. Santosa Y, Purnamasari I, Wahyuni I. 2017. Comparison of butterfly diversity in forested area and oil palm plantation. Pros Sem Nas Masy Biodiv Indon 7: 104-109. Land use change from the forested area into oil palm monoculture plantations was suspected to have reduced the number of biodiversities, including butterfly. In addressing such issues, this research was conducted from March to April 2016 in PT. Mitra Unggul Pusaka oil palm plantation of Riau Province and the forest area around the plantation. Data were collected from secondary forest and High Conservation Value representing forest areas, and oil palm plantations representing non-forest areas (young-growth oil palm and old-growth oil palm simultaneously using 3 repetitions with time search method for 3 hours (8-10 pm. The results showed that there were 30 species (117 individuals found belonging to five families, i.e.: Papilionidae (3 species, Nymphalidae (17 species, Pieridae (5 species, Lycaenidae (4 species, and Hesperidae (1 species. Species richness was greater in a forested area (Dmg=7.35 than in non-forested areas (Dmg=3.16. Based on the Similarity Index, 50% of the species in forested area were also found in non-forested areas. Therefore, it could be concluded that butterfly diversity in forested areas was higher than non-forested areas (oil palms.

  1. Conceptual design of semi-automatic wheelbarrow to overcome ergonomics problems among palm oil plantation workers

    Science.gov (United States)

    Nawik, N. S. M.; Deros, B. M.; Rahman, M. N. A.; Sukadarin, E. H.; Nordin, N.; Tamrin, S. B. M.; Bakar, S. A.; Norzan, M. L.

    2015-12-01

    An ergonomics problem is one of the main issues faced by palm oil plantation workers especially during harvesting and collecting of fresh fruit bunches (FFB). Intensive manual handling and labor activities involved have been associated with high prevalence of musculoskeletal disorders (MSDs) among palm oil plantation workers. New and safe technology on machines and equipment in palm oil plantation are very important in order to help workers reduce risks and injuries while working. The aim of this research is to improve the design of a wheelbarrow, which is suitable for workers and a small size oil palm plantation. The wheelbarrow design was drawn using CATIA ergonomic features. The characteristic of ergonomics assessment is performed by comparing the existing design of wheelbarrow. Conceptual design was developed based on the problems that have been reported by workers. From the analysis of the problem, finally have resulting concept design the ergonomic quality of semi-automatic wheelbarrow with safe and suitable used for palm oil plantation workers.

  2. Replacing rubber plantations by rain forest in Southwest China--who would gain and how much?

    Science.gov (United States)

    Ahlheim, Michael; Börger, Tobias; Frör, Oliver

    2015-02-01

    The cultivation of rubber trees in Xishuangbanna Prefecture in China's Yunnan Province has triggered an unprecedented economic development but it is also associated with severe environmental problems. Rubber plantations are encroaching the indigenous rain forests at a large scale and a high speed in Xishuangbanna. Many rare plant and animal species are endangered by this development, the natural water management is disturbed, and even the microclimate in this region has changed over the past years. The present study aims at an assessment of the environmental benefits accruing from a reforestation project partly reversing the deforestation that has taken place over the past years. To this end, a Contingent Valuation survey has been conducted in Xishuangbanna to elicit local residents' willingness to pay for this reforestation program that converts existing rubber plantations back into forest. It is shown that local people's awareness of the environmental problems caused by increasing rubber plantation is quite high and that in spite of the economic advantages of rubber plantation there is a positive willingness among the local population to contribute financially to a reduction of existing rubber plantations for the sake of a partial restoration of the local rain forest. These results could be used for the practical implementation of a Payments for Eco-System Services system for reforestation in Xishuangbanna.

  3. Ranking of industrial forest plantations in terms of sustainability: A multicriteria approach.

    Science.gov (United States)

    Diaz-Balteiro, L; Alfranca, O; González-Pachón, J; Romero, C

    2016-09-15

    As forest managers and owners must have precise assessments of sustainability, in this study we have proposed a methodology based on multi-criteria techniques for assessing sustainability in industrial forest plantations and establishing a ranking of these plantations in terms of sustainability. First, we identified and have briefly described a set of sustainability indicators (economic, environmental and social). Next, we developed a statistical procedure to determine if a linear relationship existed between the indicators. With this analysis, the final set of indicators was defined and normalized. Then, we formulated four goal programming models, by which to aggregate the different indicators. In these models, we introduced the preferences of the decision makers for each indicator, using a survey with questions formulated in a pairwise comparison format. The procedure was applied to 30 Eucalyptus globulus Labill. plantations in northwestern Spain and 11 indicators were selected in order to define the sustainability. The results showed several rankings under each goal programming model. Although the results may not be the same in the different models, some plantations are always the most sustainable, while others are always the worst in terms of sustainability. The combination of initial values of indicators, goal programming models and preferences of stakeholders (preferential weights and targets) influence the results, and it cannot be predicted a priori which plantation is the best/worst in terms of sustainability. In our case study, we show how changes in preferential weights and targets substantially modify the results obtained. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. THE POSSIBILITY OF USING TIMBER FROM PLANTATION FOREST TREATED WITH PLASTIC AND CCB FOR MARINE CONSTRUCTION

    Directory of Open Access Journals (Sweden)

    Mohammad Muslich

    2008-06-01

    Full Text Available Recently, timber  estate or plantation forest plays an important role on wooden based industries.  However, the  plantation timber  quality is relatively low.  Some treatments  have been developed to improve  its low quality, such as preservation with CCB (Chromate Copper Boron and impregnation with plastic compounds. This study is to compare the durability of timber treated with  plastic and CCB,  non-treated from plantation forest timber  as well  as from natural  forest. The plantation timber  studied were  jeungjing  (Paraserianthes falcataria, damar  (Agathis sp., pinus  (Pinus merkusii, and rubberwood (Hevea brasilliensis. Non-treated timbers that usually used for marine construction were ulin (Eusideroxylon zwageri, jati/teak  (Tectona grandis, laban (Vitex pubescens and merbau  (Instia bijuga. After  6 and 12 months,  the results showed that CCB  preserved  timber  were  more durable  than plastic  impregnated timber  and non- treated timber. Wood samples were mostly attacked by marine borer organisms from the family of  Pholadidae  and Teredinidae. The experiment results revealed the possibility of using those plantation forest timber species for marine construction purposes.

  5. [Community structure of soil fauna in Eucalyptus grandis plantations at different slope locations].

    Science.gov (United States)

    Zhao, Yu; Zhong, Yu; Zhang, Jian; Yang, Wan-qin

    2010-09-01

    To understand the effects of slope location on the community structure of soil fauna in Eucalyptus grandis plantation, an investigation was made on the soil fauna in 3 E. grandis plantations at different slope locations in the hilly area of Sichuan Province from January to October 2009. A total of 39,2762 individuals were observed, belonging to 146 groups, 7 phyla, 16 classes, and 31 orders. The community composition, trophic group, diversity, and seasonal dynamics of soil fauna in the plantations all varied with slope. The abundance of macro-fauna, xeric meso- and micro-fauna, saprophagous macro-fauna, and omnivorous xeric meso- and micro-fauna increased with the decrease of slope, indicating that soil fauna had sensitive responses to the soil environmental factors affected by slope. Significant differences in the diversity of soil saprophagous macro-fauna and hygrophilous meso- and micro-fauna were observed at different slope locations, suggesting that these two faunal groups could be used as the indicators of the habitat heterogeneity of E. grandis plantations at different slope. Overall, slope location had definite effects on the community structure and distribution of soil fauna in the E. grandis plantations, but the effects were not statistically significant.

  6. Unexpected ecological resilience in Bornean orangutans and implications for pulp and paper plantation management.

    Directory of Open Access Journals (Sweden)

    Erik Meijaard

    Full Text Available Ecological studies of orangutans have almost exclusively focused on populations living in primary or selectively logged rainforest. The response of orangutans to severe habitat degradation remains therefore poorly understood. Most experts assume that viable populations cannot survive outside undisturbed or slightly disturbed forests. This is a concern because nearly 75% of all orangutans live outside protected areas, where degradation of natural forests is likely to occur, or where these are replaced by planted forests. To improve our understanding of orangutan survival in highly altered forest habitats, we conducted population density surveys in two pulp and paper plantation concessions in East Kalimantan, Indonesia. These plantations consist of areas planted with fast-growing exotics intermixed with stands of highly degraded forests and scrublands. Our rapid surveys indicate unexpectedly high orangutan densities in plantation landscapes dominated by Acacia spp., although it remains unclear whether such landscapes can maintain long-term viable populations. These findings indicate the need to better understand how plantation-dominated landscapes can potentially be incorporated into orangutan conservation planning. Although we emphasize that plantations have less value for overall biodiversity conservation than natural forests, they could potentially boost the chances of orangutan survival. Our findings are based on a relatively short study and various methodological issues need to be addressed, but they suggest that orangutans may be more ecologically flexible than previously thought.

  7. Eucalypt plantations reduce the diversity of macroinvertebrates in small forested streams

    Directory of Open Access Journals (Sweden)

    Cordero–Rivera, A.

    2017-01-01

    Full Text Available Land use patterns of a river basin have a significant effect on the structure and function of river ecosystems. Changes in the composition of riparian plant communities modify the quantity, quality and seasonality of leaf–litter inputs, determining changes in macroinvertebrate colonization and activity. The main goal of this study was to test the effect of land–use modifications, and particularly the impact of eucalypt plantations, on the macroinvertebrate communities of sixteen headwater streams. Macroinvertebrates were counted and identified to family level. Land uses were classified in five categories using aerial photography: native forest, eucalypt plantations, agricultural land, shrubland, and urban areas. We found that macroinvertebrate diversity increased with basin size and with the proportion of basin covered by native forest. This variable correlated negatively with the land occupied by eucalypt plantations. Macroinvertebrate richness diminished with the increase of land surface covered by eucalypt plantations, and a similar tendency was observed with diversity. Furthermore, streams whose drainage basin was mainly covered by Eucalyptus were more likely to dry up in summer. This observation adds to evidence from previous studies that concluded that fast–growing tree plantations affect hydric resources, an important ecosystem service in the context of global warming. To minimize the impact of industrial sylviculture, we suggest that maintaining and/or restoring riparian forests could mitigate the effects of intensive eucalypt monocultures.

  8. Plutonium in coniferous forests

    Energy Technology Data Exchange (ETDEWEB)

    Rantavaara, A.; Kostiainen, E. [STUK - Radiation and Nuclear Safety Authority, Helsinki (Finland)

    2002-04-01

    Our aim was to study the uptake of plutonium by trees, undervegetation and some wild foods. The ratio of {sup 238}Pu/{sup 239,240}Pu in soil samples was determined for comparisons of the fallout origin. In twelve years the Chernobyl derived plutonium has not reached the mineral soil. This refers to a very slow downward migration in podsolic soil. The study confirmed also the low Pu uptake by vegetation and an insignificant contribution to human doses through wild foods. (au)

  9. Leap frog in slow motion: Divergent responses of tree species and life stages to climatic warming in Great Basin subalpine forests.

    Science.gov (United States)

    Smithers, Brian V; North, Malcolm P; Millar, Constance I; Latimer, Andrew M

    2018-02-01

    In response to climate warming, subalpine treelines are expected to move up in elevation since treelines are generally controlled by growing season temperature. Where treeline is advancing, dispersal differences and early life stage environmental tolerances are likely to affect how species expand their ranges. Species with an establishment advantage will colonize newly available habitat first, potentially excluding species that have slower establishment rates. Using a network of plots across five mountain ranges, we described patterns of upslope elevational range shift for the two dominant Great Basin subalpine species, limber pine and Great Basin bristlecone pine. We found that the Great Basin treeline for these species is expanding upslope with a mean vertical elevation shift of 19.1 m since 1950, which is lower than what we might expect based on temperature increases alone. The largest advances were on limber pine-dominated granitic soils, on west aspects, and at lower latitudes. Bristlecone pine juveniles establishing above treeline share some environmental associations with bristlecone adults. Limber pine above-treeline juveniles, in contrast, are prevalent across environmental conditions and share few environmental associations with limber pine adults. Strikingly, limber pine is establishing above treeline throughout the region without regard to site characteristic such as soil type, slope, aspect, or soil texture. Although limber pine is often rare at treeline where it coexists with bristlecone pine, limber pine juveniles dominate above treeline even on calcareous soils that are core bristlecone pine habitat. Limber pine is successfully "leap-frogging" over bristlecone pine, probably because of its strong dispersal advantage and broader tolerances for establishment. This early-stage dominance indicates the potential for the species composition of treeline to change in response to climate change. More broadly, it shows how species differences in dispersal

  10. Combustion influences on natural abundance nitrogen isotope ratio in soil and plants following a wildfire in a sub-alpine ecosystem.

    Science.gov (United States)

    Huber, Edith; Bell, Tina L; Adams, Mark A

    2013-11-01

    This before-and-after-impact study uses the natural abundance N isotope ratio (δ(15)N) to investigate the effects of a wildfire on sub-alpine ecosystem properties and processes. We measured the (15)N signatures of soil, charred organic material, ash and foliage in three sub-alpine plant communities (grassland, heathland and woodland) in south-eastern Australia. Surface bulk soil was temporarily enriched in (15)N immediately after wildfire compared to charred organic material and ash in all plant communities. We associated the enrichment of bulk soil with fractionation of N during combustion and volatilization of N, a process that also explains the sequential enrichment of (15)N of unburnt leaves > ash > charred organic material in relation to duration and intensity of heating. The rapid decline in (15)N of bulk soil to pre-fire values indicates that depleted ash, containing considerable amounts of total N, was readily incorporated into the soil. Foliar δ(15)N also increased with values peaking 1 year post-fire. Foliar enrichment was foremost coupled with the release of enriched NH4(+) into the soil owing to isotopic discrimination during volatilization of soluble N and combustion of organic material. The mode of post-fire regeneration influenced foliar (15)N enrichment in two species indicating use of different sources of N following fire. The use of natural abundance of (15)N in soil, ash and foliage as a means of tracing transformation of N during wildfire has established the importance of combustion products as an important, albeit temporary source of inorganic N for plants regenerating after wildfire.

  11. [Contribution of soil fauna to the mass loss of Betula albosinensis leaf litter at early decomposition stage of subalpine forest litter in western Sichuan].

    Science.gov (United States)

    Xia, Lei; Wu, Fu-Zhong; Yang, Wan-Qin; Tan, Bo

    2012-02-01

    In order to quantify the contribution of soil fauna to the decomposition of birch (Betula albosinensis) leaf litter in subalpine forests in western Sichuan of Southwest China during freeze-thaw season, a field experiment with different mesh sizes (0.02, 0.125, 1 and 3 mm) of litterbags was conducted in a representative birch-fir (Abies faxoniana) forest to investigate the mass loss rate of the birch leaf litter from 26 October, 2010 to 18 April, 2011, and the contributions of micro-, meso- and macro-fauna to the decomposition of the leaf litter. Over the freeze-thaw season, 11.8%, 13.2%, 15.4% and 19.5% of the mass loss were detected in the litterbags with 0.02, 0. 125, 1 and 3 mm mesh sizes, respectively. The total contribution of soil fauna to the litter decomposition accounted for 39.5% of the mass loss, and the taxa and individual relative density of the soil fauna in the litterbags had the similar variation trend with that of the mass loss rate. The contribution rate of soil fauna to the leaf litter mass loss showed the order of micro- fauna, with the highest contribution of micro-fauna (7.9%), meso-fauna (11.9%), and macro-fauna (22.7%) at the onset of freezing stage, deeply frozen stage, and thawing stage, respectively. The results demonstrated that soil fauna played an important role in the litter decomposition in subalpine forests of western Sichuan during freeze-thaw season.

  12. Seasonal dynamics of the plant community and soil seed bank along a successional gradient in a subalpine meadow on the Tibetan Plateau.

    Directory of Open Access Journals (Sweden)

    Miaojun Ma

    Full Text Available BACKGROUND: Knowledge about how change the importance of soil seed bank and relationship between seed mass and abundance during vegetation succession is crucial for understanding vegetation dynamics. Many studies have been conducted, but their ecological mechanisms of community assembly are not fully understood. METHODOLOGY: We examined the seasonal dynamics of the vegetation and soil seed bank as well as seed size distribution along a successional gradient. We also explored the potential role of the soil seed bank in plant community regeneration, the relationship between seed mass and species abundance, and the relative importance of deterministic and stochastic processes along a successional gradient. PRINCIPAL FINDINGS: Species richness of seed bank increased (shallow layer and the total and seed density decreased (each layer and the total significantly with succession. Species richness and seed density differed significantly between different seasons and among soil depths. Seed mass showed a significant negative relationship with relative abundance in the earliest successional stage, but the relationships were not significant in later stages. Seed mass showed no relationship with relative abundance in the whole successional series in seed bank. Results were similar for both July 2005 and April 2006. CONCLUSIONS: The seed mass and abundance relationship was determined by a complex interaction between small and larger seeded species and environmental factors. Both stochastic processes and deterministic processes were important determinants of the structure of the earliest stage. The importance of seed bank decreased with succession. The restoration of abandoned farmed and grazed meadows to the species-rich subalpine meadow in Tibetan Plateau can be successfully achieved from the soil seed bank. However, at least 20 years are required to fully restore an abandoned agricultural meadow to a natural mature subalpine meadow.

  13. Fine root dynamics in a developing Populus deltoides plantation.

    Science.gov (United States)

    Kern, Christel C; Friend, Alexander L; Johnson, Jane M-F; Coleman, Mark D

    2004-06-01

    A closely spaced (1 x 1 m) cottonwood (Populus deltoides Bartr.) plantation was established to evaluate the effects of nutrient availability on fine root dynamics. Slow-release fertilizer (17:6:12 N,P,K plus micronutrients) was applied to 225-m(2) plots at 0, 50, 100 and 200 kg N ha(-1), and plots were monitored for two growing seasons. Fine root production, mortality, live root standing crop and life span were analyzed based on monthly minirhizotron observations. Fine root biomass was measured in soil cores. Fine root dynamics were controlled more by temporal, depth and root diameter factors than by fertilization. Cumulative fine root production and mortality showed strong seasonal patterns; production was greatest in the middle of the growing season and mortality was greatest after the growing season. Small diameter roots at shallow soil depths cycled more rapidly than larger or deeper roots. The strongest treatment effects were found in the most rapidly cycling roots. The standing crop of live roots increased with fertilizer treatment according to both minirhizotron and soil coring methods. However, production and mortality had unique treatment response patterns. Although cumulative mortality decreased in response to increased fertilization, cumulative production was intermediate at 0 kg N ha(-1), lowest with 50 kg N ha (-1), and highest with 200 kg N ha(-1). Aboveground growth responded positively to fertilization up to an application rate of 50 kg N ha(-1), but no further increases in growth were observed despite a threefold increase in application rate. Median fine root life span varied from 307 to over 700 days and increased with depth, diameter and nutrient availability.

  14. Mercury bioaccumulation in fishes from subalpine lakes of the Wallowa-Whitman National Forest, northeastern Oregon and western Idaho

    Science.gov (United States)

    Eagles-Smith, Collin A.; Herring, Garth; Johnson, Branden L.; Graw, Rick

    2013-01-01

    Mercury (Hg) is a globally distributed pollutant that poses considerable risks to human and wildlife health. Over the past 150 years since the advent of the industrial revolution, approximately 80 percent of global emissions have come from anthropogenic sources, largely fossil fuel combustion. As a result, atmospheric deposition of Hg has increased by up to 4-fold above pre-industrial times. Because of their isolation, remote high-elevation lakes represent unique environments for evaluating the bioaccumulation of atmospherically deposited Hg through freshwater food webs, as well as for evaluating the relative importance of Hg loading versus landscape influences on Hg bioaccumulation. The increase in Hg deposition to these systems over the past century, coupled with their limited exposure to direct anthropogenic disturbance make them useful indicators for estimating how changes in Hg emissions may propagate to changes in Hg bioaccumulation and ecological risk. In this study, we evaluated Hg concentrations in fishes of high-elevation, sub-alpine lakes in the Wallowa-Whitman National Forest in northeastern Oregon and western Idaho. Our goals were to (1) assess the magnitude of Hg contamination in small-catchment lakes to evaluate the risk of atmospheric Hg to human and wildlife health, (2) quantify the spatial variability in fish Hg concentrations, and (3) determine the ecological, limnological, and landscape factors that are best correlated with fish total mercury (THg) concentrations in these systems. Across the 28 study lakes, mean THg concentrations of resident salmonid fishes varied as much as 18-fold among lakes. Importantly, our top statistical model explained 87 percent of the variability in fish THg concentrations among lakes with four key landscape and limnological variables— catchment conifer density (basal area of conifers within a lake’s catchment), lake surface area, aqueous dissolved sulfate, and dissolved organic carbon. The basal area of conifers

  15. Characterizing water, energy and CO2 exchange for a Sky Island subalpine forest in the southwestern USA

    Science.gov (United States)

    Brown-Mitic, C. M.; Shuttleworth, J.; Harlow, C.; Bales, R.

    2003-04-01

    Among the ecosystems present in the semi-arid environment of the Southwestern U.S., Sky Island forest is unique and it has a unique relationship to the sparse surface-water resources available in the region. This ecosystem exists only at the top of mountains because it is only here that, as a long-term average, precipitation input exceeds evapotranspiration to the extent that forest vegetation can survive. Sky Island Forests, therefore, command potentially significant source areas for the water (some originally falling as snow) that ultimately leaves topographically high ground to recharge aquifers in the plains below by mountain-front recharge. They are also very recently recognized as important carbon sinks where very little or no understanding exist of the exchange/cycling dynamics. The Mount Bigelow project provides an empirically based understanding of the hydro- micrometeorological dynamics of a sky island sub-alpine forest in the southwestern U.S. It is the first study to attempt to document, understand, and model the water, energy, and (related) carbon exchanges of the uniquely interesting and, from the water resource standpoint, uniquely important Sky Island forest ecosystem. The fundamental science issues addressed are: the characteristics of the surface-atmosphere exchanges of water, energy and carbon; the storage of moisture and energy in plants and soil; partitioning of winter snow and rain between evapotranspiration/sublimation, deep drainage and the near-surface environmental water resource that sustains the forest. In order to achieve our objective, a network of four below canopy hydro-micrometeorological stations 10 m tall, and one above canopy 30 m tall high resolution eddy correlation tower, were deployed within a predominantly douglas fir/pine second growth forest. Our observations indicate that the surface flux potential (i.e. sensible heat flux (H) potential), defined as the surface-air temperature gradient varies significantly over space as

  16. Rock fragment cover controls the sediment detachment in citrus plantations

    Science.gov (United States)

    Cerdà, Artemi; Keesstra, Saskia; Hamidreza Sadeghi, Seyed; Brevik, Eric; Giménez Morera, Antonio; Novara, Agata; Masto, Reginald E.; Jordán, Antonio; Wang, Juan

    2016-04-01

    conditions. The objective of this research is to determine the impact of the rock fragment cover on soil and water losses in citrus plantations. Within the Corral Roig Soil Erosion Research Station, located in the Municipality of Montesa, 82 plots were selected with different rock fragment cover. In each circular plot of 0.25 m2, a rainfall simulation experiments was carried out at 55 mm h-1 of rainfall intensity during 1 hour under dry conditions in the Summer of 2013 under very dry conditions. It was found that the soil erosion rates are related to percentage of bare soil, and negatively correlated to the rock fragment covers. A cover of 30 % of rock fragments reduces the loss of soil with 81%. Acknowledgements The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement n° 603498 (RECARE project). References Cerdà, A. 1999. Parent material and vegetation affect soil erosion in eastern Spain. Soil Science Society of America Journal, 63 (2), 362-368. Cerdà, A., Giménez-Morera, A. and Bodí, M.B. Soil and water losses from new citrus orchards growing on sloped soils in the western Mediterranean basin. Earth Surface Processes and Landforms, 34, 1822-1830. 2009. DOI: 10.1002/esp.1889 Cerdà, A., González-Pelayo, O., Giménez-Morera, A., Jordán, A., Pereira, P., Novara, A., Brevik, E.C., Prosdocimi, M., Mahmoodabadi, M., Keesstra, S., García Orenes, F., Ritsema, C., 2015. The use of barley straw residues to avoid high erosion and runoff rates on persimmon plantations in Eastern Spain under low frequency - high magnitude simulated rainfall events. Soil Res. (In press) Cerdà, A., Jurgensen, M.F. 2011. Ant mounds as a source of sediment on citrus orchard plantations in eastern Spain. A three-scale rainfall simulation approachCatena, 85 (3), 231-236. DOI: 10.1016/j.catena.2011.01.008 Cerdà, A., Jurgensen, M.F. 2008.The influence of ants on soil and water losses from an orange orchard in

  17. [Soil moisture content and fine root biomass of rubber tree (Hevea brasiliensis) plantations at different ages].

    Science.gov (United States)

    Lin, Xi-Hao; Chen, Qiu-Bo; Hua, Yuan-Gang; Yang, Li-Fu; Wang, Zhen-Hui

    2011-02-01

    By using soil core sampling method, this paper studied the soil moisture regime of rubber plantations and the fine root biomass of Hevea brasiliensis in immature period (5 a), early yielding period (9 a), and peak yielding period (16 a). With the increasing age of rubber trees, the soil moisture content of rubber plantations increased but the fine root biomass decreased. The soil moisture content at the depth of 0-60 cm in test rubber plantations increased with soil depth, and presented a double-peak pattern over the period of one year. The fine root biomass of rubber trees at different ages had the maximum value in the top 10 cm soil layers and decreased with soil depth, its seasonal variation also showed a double-peak pattern, but the peak values appeared at different time. Soil moisture content and soil depth were the main factors affecting the fine root biomass of H. brasiliensis.

  18. Seasonality of pathogenic fungi in mites of rubber tree plantations adjacent to fragments of Cerrado

    Directory of Open Access Journals (Sweden)

    PR. Demite

    Full Text Available Fungi are the most frequently observed pathogens of mite populations, helping to control them on different crops. Twenty-five samples of leaves were collected from rubber tree plantations adjacent to two fragments of Cerrado vegetation. Each rubber tree plantation had 25 plants selected for sampling and seven leaves from around each tree top were collected up to seven to eight meters above ground. Approximately 250 individuals of Calacarus heveae Feres, Phyllocoptruta seringueirae Feres, and Tenuipalpus heveae Baker, collected randomly, were mounted from each plantation. Hirsutella thompsoni Fisher was observed on all three mites and T. heveae was the most infected species. The highest infestation levels occurred from November to February (rainy season. In the dry season, infestation levels were below 5%. Hirsutella thompsonii has potential to be used as mycoacaricide during the rainy season.

  19. Impacts of fertilizer additions on water quality of a drained pine plantation in North Carolina. A worst case scenario.

    Science.gov (United States)

    Bray J. Beltran; Devendra M. Amatya; Martin Jones; R. Wayne Skaggs; William Neal P.E. Reynolds; Timothy J. Callahan; Jami E. Nettles

    2008-01-01

    Intensive plantation forestry will be increasingly important in the next 50 years to meet the high demand for domestic wood in the US. However, forestry management practices can substantially influence downstream water quality and ecology. In this study, the effect of fertilization on drainage water quality of a coastal pine plantation located in Carteret County, NC...

  20. Tropical and Highland Temperate Forest Plantations in Mexico: Pathways for Climate Change Mitigation and Ecosystem Services Delivery

    Directory of Open Access Journals (Sweden)

    Vidal Guerra-De la Cruz

    2017-12-01

    Full Text Available Forest plantations are a possible way of increasing forest productivity in temperate and tropical forests, and therefore also increasing above- and belowground carbon pools. In the context of climate change, monospecific plantations might become an alternative to mitigate global warming; however, their contribution to the structural complexity, complementarity, and biodiversity of forests has not been addressed. Mixed forest plantations can ensure that objectives of climate change mitigation are met through carbon sequestration, while also delivering anticipated ecosystem services (e.g., nutrient cycling, erosion control, and wildlife habitat. However, mixed forest plantations pose considerable operational challenges and research opportunities. For example, it is essential to know how many species or functional traits are necessary to deliver a set of benefits, or what mixture of species and densities are key to maintaining productive plantations and delivering multiple ecosystem services. At the same time, the establishment of forest plantations in Mexico should not be motivated solely by timber production. Forest plantations should also increase carbon sequestration, maintain biodiversity, and provide other ecosystem services. This article analyzes some matters that affect the development of planted forests in the Mexican national context, and presents alternatives for forest resources management through the recommendation of mixed forest plantations as a means of contributing to climate change mitigation and the delivery of ecosystem services.

  1. Soil carbon and nitrogen sequestration over an age sequence of Pinus patula plantations in Zimbabwean Eastern Highlands

    NARCIS (Netherlands)

    Mujuru, L.; Gotora, T.; Velthorst, E.J.; Nyamangara, J.; Hoosbeek, M.R.

    2014-01-01

    Forests play a major role in regulating the rate of increase of global atmospheric carbon dioxide (CO2) concentrations creating a need to investigate the ability of exotic plantations to sequester atmospheric CO2. This study examined pine plantations located in the Eastern Highlands of Zimbabwe

  2. Strong effects of a plantation with Pinus patula on Andean Subparamo vegetation: a case study from Columbia

    NARCIS (Netherlands)

    Wesenbeeck, van B.K.; Mourik, van T.A.; Duivenvoorden, J.F.; Cleef, A.M.

    2003-01-01

    The effect of a pine plantation on a native subparamo system in the Andes of Colombia (3 100 In above sea level) was studied. The vegetation of an 8 year-old plantation with Pinus patula was compared to that of the surrounding native subparamo. 59 plots made in the subparamo vegetation contained 121

  3. Influence of establishment timing and planting stock on early rotational growth of loblolly pine plantations in Texas

    Science.gov (United States)

    M. A. Blazier; E. L. Taylor; A. G. Holley

    2010-01-01

    Planting container seedlings, which have relatively fully formed root systems encased in a soil-filled plug, may improve loblolly pine plantation productivity by increasing early survival and growth relative to that of conventionally planted bareroot seedlings. Planting seedlings in fall may also confer productivity increases to loblolly pine plantations by giving...

  4. Pinestraw raking, fertilization and poultry litter amendment effects on soil physical properties for a mid-rotation loblolly pine plantation

    Science.gov (United States)

    William B. Patterson; Michael A. Blazier; Steven L. Holtard

    2010-01-01

    Frequent pinestraw raking and removal in pine plantations has led to concerns about nutrient removal from the stand. While soil chemistry of raked stands has been studied, little attention has been placed on potential compaction from raking operations. Four treatments were applied to a 16-year-old loblolly pine plantation at the Louisiana State University AgCenter...

  5. Hierarchical, parallel computing strategies using component object model for process modelling responses of forest plantations to interacting multiple stresses

    Science.gov (United States)

    J. G. Isebrands; G. E. Host; K. Lenz; G. Wu; H. W. Stech

    2000-01-01

    Process models are powerful research tools for assessing the effects of multiple environmental stresses on forest plantations. These models are driven by interacting environmental variables and often include genetic factors necessary for assessing forest plantation growth over a range of different site, climate, and silvicultural conditions. However, process models are...

  6. Soil labile organic carbon and carbon-cycle enzyme activities under different thinning intensities in Chinese fir plantations

    NARCIS (Netherlands)

    Chen, Xinli; Chen, Han Y.H.; Chen, Xin; Wang, Jing; Chen, Bin; Wang, Dong; Guan, Qingwei

    2016-01-01

    Thinning is a silvicultural tool that is used to facilitate the growth of timber plantations worldwide. Plantations are important CO2 sinks, but the mechanism by which thinning affects the quantity and stability of soil organic carbon (SOC) is poorly understood. In this study, we

  7. Mapping aboveground carbon stocks using LiDAR data in Eucalyptus spp. plantations in the state of Sao Paulo, Brazil

    Science.gov (United States)

    Carlos Alberto Silva; Carine Klauberg; Samuel de Padua Chaves e Carvalho; Andrew T. Hudak; e Luiz Carlos Estraviz. Rodriguez

    2014-01-01

    Fast growing plantation forests provide a low-cost means to sequester carbon for greenhouse gas abatement. The aim of this study was to evaluate airborne LiDAR (Light Detection And Ranging) to predict aboveground carbon (AGC) stocks in Eucalyptus spp. plantations. Biometric parameters (tree height (Ht) and diameter at breast height (DBH)) were collected from...

  8. Bioenergy and carbon sequestration potential from energy tree plantation in rural wasteland of North-Eastern India

    NARCIS (Netherlands)

    Hiloidhari, Moonmoon; Medhi, Hemantajeet; Das, Karabee; Thakur, Indu Shekhar; Baruah, Debendra Chandra

    2016-01-01

    In this study, carbon sequestration potential via energy tree plantation in the rural wasteland of Assam, India was estimated under two different plantation species scenarios,viz., (i) Acacia nilotica, and (ii) Bambusa tulda. Furthermore, CO2 emission reduction potential in local tea industries by

  9. Snow breakage in a pole-sized ponderosa pine plantation ... more damage at high stand-densities

    Science.gov (United States)

    Robert F. Powers; William W. Oliver

    1970-01-01

    Damage by snow breakage to pole-sized ponderosa pine (Pinus pondvosa Laws.) increased as stand density increased. In a plantation on the west slope of California's Sierra Nevada, the tallest trees were most often broken. Thinning in the sapling stage is recommended as a preventative measure in dense plantations subject to heavy snowfall.

  10. Potential implications for expansion of freeze-tolerant eucalyptus plantations on water resources in the southern United States

    Science.gov (United States)

    James M. Vose; Chelcy F. Miniat; Ge Sun; Peter V. Caldwell

    2014-01-01

    The potential expansion of freeze-tolerant (FT) Eucalyptus plantations in the United States has raised concerns about the implications for water resources. Modeling was used to examine the potential effects of expanding the distribution of FT Eucalyptus plantations in US Department of Agriculture Plant Hardiness Zones 8b and...

  11. Crisis and neoliberal reforms in Africa : civil society and agro-industry in anglophone Cameroon's plantation economy

    NARCIS (Netherlands)

    Konings, P.J.J.

    2011-01-01

    This book discusses the consequences of the economic and financial crisis that befell the Cameroonian agro-industrial sector in the 1980s, using as a case study the plantation economy of the anglophone region of Cameroon. Two agro-industrial enterprises have dominated the plantation sector: a huge

  12. Using short-rotation, intensively managed hardwood plantations as ‘green’ inventory for southeastern U.S

    Science.gov (United States)

    Tom Gallagher; Bob Shaffer; Bob Rummer

    2008-01-01

    As a routine wood source for a pulp mill, recent studies have shown that intensively managed, short-rotation hardwood plantations are not cost effective. The objective of this study was to determine if these plantations may be cost effective as "green" inventory, replacing some portion of high cost remote woodyard inventory. Three southeastern U.S. pulp mills...

  13. Impacts of fertilizer additions on water quality of a drained pine plantation in North Carolina. A worst case scenario.

    Science.gov (United States)

    Bray J. Beltran; Devendra M. Amatya; Martin Jones; R. Wayne Skaggs; William Neal Reynolds; Timothy J. Callahan; Jami E. Nettles

    2008-01-01

    Abstract. Intensive plantation forestry will be increasingly important in the next 50 years to meet the high demand for domestic wood in the US. However, forestry management practices can substantially influence downstream water quality and ecology. In this study, the effect of fertilization on drainage water quality of a coastal pine plantation located in Carteret...

  14. A principal component approach for predicting the stem volume in Eucalyptus plantations in Brazil using airborne LiDAR data

    Science.gov (United States)

    Carlos Alberto Silva; Carine Klauberg; Andrew T. Hudak; Lee A. Vierling; Veraldo Liesenberg; Samuel P. C. e Carvalho; Luiz C. E. Rodriguez

    2016-01-01

    Improving management practices in industrial forest plantations may increase production efficiencies, thereby reducing pressures on native tropical forests for meeting global pulp needs. This study aims to predict stem volume (V) in plantations of fast-growing Eucalyptus hybrid clones located in southeast Brazil using field plot and airborne Light Detection...

  15. Biophysical Impacts of Tropical Land Transformation from Forest to Oil Palm and Rubber Plantations in Indonesia

    Science.gov (United States)

    Knohl, Alexander; Meijide, Ana; Fan, Yuanchao; Gunawan, Dodo; Hölscher, Dirk; June, Tania; Niu, Furong; Panferov, Oleg; Ringeler, Andre; Röll, Alexander; Sabajo, Clifton; Tiralla, Nina

    2016-04-01

    Indonesia currently experiences rapid and large-scale land-use changes resulting in forest loss and the expansion of cash crop plantations such as oil palm and rubber. Such land transformations are associated with changes in surface properties that affect biophysical processes influencing the atmosphere. Yet, the overall effect of such land transformations on the atmosphere at local and regional scale remains unclear. In our study, we combine measurements of microclimate, transpiration via sap-flux, surface energy fluxes via eddy covariance, surface temperature via remote sensing, land surface (CLM) and regional climate modeling (WRF) for Jambi Province in Indonesia. Our microclimatic measurements showed that air temperature within the canopy was on average 0.7-0.8°C higher in monoculture plantations (oil palm and rubber) compared to forest. Remote sensing analysis using MODIS and Landsat revealed a higher canopy surface temperature for oil palm plantations (+1.5°C) compared to forest, but only little differences for rubber plantations. Transpiration (T) and evapotranspiration (ET) as well as the contribution of T to ET of oil palm showed a strong age-dependent increase. The sensible to latent heat flux ratio decreased with age. Overall, rubber plantations showed the lowest transpirations rates (320 mm year-1), oil palm intermediate rates (414 mm year-1), and forest the highest rates (558 mm year-1) indicating substantial differences in water use. Despite the differences in water use and the higher within-canopy and surface temperatures of the plantations compared to the forest, there was only a minor effect of land transformation on the atmosphere at the regional scale (<0.2 °C), irrespectively of the large spatial extend of the transformation. In conclusion, our study shows a strong local scale biophysical impact affecting the conditions at the stand level, which is however mitigated in the atmosphere at the regional level.

  16. Occupancy and abundance of Eleutherodactylus frogs in coffee plantations in Puerto Rico

    Science.gov (United States)

    Monroe, Kelen D.; Collazo, Jaime A.; Pacifici, Krishna; Reich, Brian J.; Puente-Rolón, Alberto R.; Terando, Adam J.

    2017-01-01

    Shaded coffee plantations are of conservation value for many taxa, particularly for resident avifauna in the face of extensive landscape changes. Yet, little is known about the value of coffee plantations for amphibians because there are scant demographic data to index their value among species with different habitat preferences. We estimated the probability of occupancy of three frog species: Eleutherodactylus wightmanae, a forest species; E. brittoni, a grassland species; and E. antillensis, an open habitat species. Occupancy was estimated in sun and shaded plantations, and in secondary forest, in the west-central mountains of Puerto Rico. We also estimated the probability that a survey station was occupied by no individuals, one, or >1 individual, as a proxy of abundance. The aforementioned parameters, and local colonization and extinction probability, were modeled as a function of weather conditions (temperature, humidity) and vegetation cover at the sampling station (5 m) and contextual (100 m) scales. Encounter histories were obtained with passive acoustic recorders between February and July in 2015. Consistent with known habitat preferences, the highest occupancies were associated with secondary forests for E. wightmanae and sun plantations for E. brittoni. Occupancy probability for E. antillensis was similar across habitat types, indicating no aversion to shaded–forested habitats. Shaded plantations harbored moderate levels of occupancy for all species, indicating their potential value for multispecies conservation. Local colonization rates increased with forest cover for E. wightmanae, and with open habitats for E. brittoni and E. antillensis. Open habitats harbored a higher abundance of E. brittoni and E antillensis, but lower values for E. wightmanae. Sun and shaded plantations could provide quality habitat for Eleutherodactylus spp. if managed for features that promote local colonization and abundance.

  17. A comparison between energy transfer and atmospheric turbulent exchanges over alpine meadow and banana plantation

    Science.gov (United States)

    Ding, Zhangwei; Ma, Yaoming; Wen, Zhiping; Ma, Weiqiang; Chen, Shiji

    2017-07-01

    Banana plantation and alpine meadow ecosystems in southern China and the Tibetan Plateau (TP) are unique in the underlying surfaces they exhibit. In this study, we used eddy covariance and a micrometeorological tower to examine the characteristics of land surface energy exchanges over a banana plantation in southern China and an alpine meadow in the Tibetan Plateau from May 2010 to August 2012. The results showed that the diurnal and seasonal variations in upward shortwave radiation flux and surface soil heat flux were larger over the alpine meadow than over the banana plantation surface. Dominant energy partitioning varied with season. Latent heat flux was the main consumer of net radiation flux in the growing season, whereas sensible heat flux was the main consumer during other periods. The Monin-Obukhov similarity theory was employed for comparative purposes, using sonic anemometer observations of flow over the surfaces of banana plantations in the humid southern China monsoon region and the semi-arid areas of the TP, and was found to be applicable. Over banana plantation and alpine meadow areas, the average surface albedo and surface aerodynamic roughness lengths under neutral atmospheric conditions were ˜0.128 and 0.47 m, and ˜0.223 and 0.01 m, respectively. During the measuring period, the mean annual bulk transfer coefficients for momentum and sensible heat were 1.47 × 10-2 and 7.13 × 10-3, and 2.91 × 10-3 and 1.96 × 10-3, for banana plantation and alpine meadow areas, respectively.

  18. [Biomass- and energy allocation in Eucalyptus urophylla x Eucalyptus tereticornis plantations at different stand ages].

    Science.gov (United States)

    Zhou, Qun-Ying; Chen, Shao-Xiong; Han, Fei-Yang; Chen, Wen-Ping; Wu, Zhi-Hua

    2010-01-01

    An investigation was made on the biomass- and energy allocation in 1-4-year-old Eucalyptus urophylla x Eucalyptus tereticornis plantations at Beipo Forest Farm of Suixi County in Guangdong Province. Stand age had significant effects on the retained biomass of the plantations (P biomass was in the range of 10.61-147.28 t x hm(-2). Both the total biomass and the biomass of above- and belowground components increased with increasing stand age. The proportions of leaf-, branch- and bark biomass to total biomass decreased with year, while that of stem biomass was in reverse. The biomass allocation of the components in 1- and 2-year-old plantations decreased in order of stem > branch > bark > root > leaf, and that in 3- and 4 -year-old plantations was in order of stem > root > branch > bark > leaf. The mean ash content (AC) of the five components at different stand ages ranged from 0.47% to 5.91%, being the highest in bark and the lowest in stem. The mean gross caloric value (GCV) and ash free caloric value (AFCV) of different components ranged from 17.33 to 20. 60 kJ x g(-1) and from 18.42 to 21.59 kJ x g(-1) respectively. Of all the components, leaf had the highest GVC and AFCV, while bark had the lowest ones. Stand age had significant effects on the GVC of branch, stem, and bark, and on the AFCV of leaf, stem, and bark (P 0.05). The retained energy of 1-4-year-old plantations ranged from 199.98 to 2837.20 GJ x hm(-2), with significant differences among the stand ages (P energy of various components and plantations increased with stand age, and the energy allocation of various components had the same trend as biomass allocation.

  19. Evapotranspiration components determined by eddy covariance and sap flux measurements in oil palm plantations in Sumatra, Indonesia

    Science.gov (United States)

    Meijide, Ana; Röll, Alexander; Niu, Furong; June, Tania; Hölscher, Dirk; Knohl, Alexander

    2015-04-01

    The expansion of oil palm cultivation fueled by the increasing global demand for palm oil is leading to massive land transformations in tropical areas, particularly in South-East Asia. Conversions of forest land to oil palm plantations likely affect ecosystem water fluxes. However, there is a lack of information on water fluxes from oil palm plantations as well as on the partitioning of these fluxes into its different components such as transpiration and evaporation. It is expected that water fluxes from oil palm plantations vary temporally, both long-term, i.e. between different age-classes of plantations, and short-term, i.e. from day to day within a certain plantation (e.g. during or after periods of rainfall). A proper evaluation of water fluxes from oil palm plantations thus requires an experimental design encompassing these types of variability. To assess evapotranspiration (ET) rates, an eddy covariance tower was installed in a 2-year-old oil palm plantation in the lowlands of Jambi, Sumatra; it was subsequently moved to a 12-year-old oil palm plantation located in the same region. In parallel to the ET, sap flux density was measured on 16 leaf petioles on four oil palms; stand transpiration rates were derived from these measurements with stand inventory data. The parallel measurements ran for several weeks in both plantations. Preliminary results for our period of study show that the average ET rate of the 2-year-old oil palm plantation was 5.2 mm day-1; values up to 7.0 mm day-1 were observed on dry, sunny days with non-limiting soil moisture. Stand transpiration (T) by the young oil palms was very low, 0.3 mm day-1on average, and only showed a small variation between days. Under optimal environmental conditions, the ratio of T to total ET was up to 0.08 in the young plantation, while in the mature, 12-year-old plantation, it was significantly higher and reached 0.5. Transpiration rates in the mature oil palm plantation were about six- to seven-fold higher

  20. Carbon budget and its response to environmental factors in young and mature poplar plantations along the middle and lower reaches of the Yangtze River, China

    Science.gov (United States)

    Jinxing Zhou; Yuan Wei; Jun Yang; Xiaohui Yang; Zeping Jiang; Jiquan Chen; Asko Noormets; Xiaosong Zhao

    2012-01-01

    Although poplar forest is the dominant plantation type in China, there is uncertainty about the carbon budget of these forests across the country. The observations, performed in 2006, of two eddy covariance flux towers on a young poplar plantation (Yueyang, Hunan province) and a mature poplar plantation (Huaining, Anhui province) provide an opportunity to understand...