scholarly journals Tree water relations can trigger monoterpene emissions from Scots pine stems during spring recovery

2015 ◽  
Vol 12 (18) ◽  
pp. 5353-5363 ◽  
Author(s):  
A. Vanhatalo ◽  
T. Chan ◽  
J. Aalto ◽  
J. F. Korhonen ◽  
P. Kolari ◽  
...  
Keyword(s):  
Scots Pine ◽  
Boreal Forests ◽  
Environmental Drivers ◽  
Emission Rates ◽  
Soil Organisms ◽  
Tree Diameter ◽  
Phenological Changes ◽  
Tree Canopies ◽  
Volatile Organic ◽  
High Emission

Abstract. Tree canopies are known to emit large amounts of VOCs (volatile organic compounds) such as monoterpenes into the surrounding air. High VOC emission rates from boreal forests have been observed during the transition from winter to summer activity. The most important sources of these are considered to be the green foliage, understory vegetation and soil organisms, but emissions from the living stand woody compartments have so far not been quantified. We analyzed whether the non-foliar components could partially explain the springtime high emission rates. We measured the monoterpene emissions from Scots pine (Pinus sylvestris L.) stem and shoots during the dehardening phase of trees in field conditions in two consecutive springs. We observed a large, transient monoterpene burst from the stem, while the shoot monoterpene emissions remained low. The burst lasted about 12 h. Simultaneously, an unusual nighttime sap flow and a non-systematic diurnal pattern of tree diameter were detected. Hence, we suggest that the monoterpene burst was a consequence of the recovery of the stem from wintertime, and likely related to the refilling of embolized tracheids and/or phenological changes in the living cells of the stem. This indicates that the dominant processes and environmental drivers triggering the monoterpene emissions are different between the stem and the foliage.

scholarly journals Tree water relations trigger monoterpene emissions from Scots pine stem during spring recovery

2015 ◽  
Vol 12 (10) ◽  
pp. 7783-7814 ◽  
Author(s):  
A. Vanhatalo ◽  
T. Chan ◽  
J. Aalto ◽  
J. F. Korhonen ◽  
P. Kolari ◽  
...  
Keyword(s):  
Organic Compounds ◽  
Scots Pine ◽  
Sap Flow ◽  
Environmental Drivers ◽  
Diurnal Pattern ◽  
Night Time ◽  
Tree Diameter ◽  
Tree Canopies ◽  
Volatile Organic ◽  
Winter Time

Abstract. Tree canopies are known to emit large amounts of VOCs (volatile organic compounds) such as monoterpenes to the surrounding air. The main source for these is considered to be the green biomass, i.e. foliage, but emissions from the woody compartments have not been quantified. A VOC emission anomaly has been observed during transition from winter to summer activity. We analyzed if non-foliar components could partially explain the anomaly. We measured the VOC emissions from Scots pine (Pinus sylvestris L.) stems and shoots during the dehardening phase of trees in field conditions in two consecutive springs. We observed a large, transient monoterpene burst from stems, while the shoot monoterpene emissions and transpiration remained low. The burst lasted about 12 h. Simultaneously, an unusual night-time sap flow and an anomalous diurnal pattern of tree diameter were detected. Hence, we suggest that the monoterpene burst was a consequence of the recovery of the stem from winter-time. This indicates that the dominant processes and environmental drivers triggering the monoterpene emissions are different between stems and foliage.

Dinamica numărului unităților de transport ca factor de poluare a aerului atmosferic în R.D. Nord a Republicii Moldova

2020 ◽  
Author(s):  
Andrian Tugulea ◽  
Keyword(s):  
Aerosol Particles ◽  
Trace Gases ◽  
Emission Rates ◽  
Common Phenomenon ◽  
Active Components ◽  
Modern Life ◽  
Volatile Organic ◽  
Large Growth ◽  
High Emission ◽  
Transport Emissions

Because of the growing vehicle population and the high emission rates, serious air pollution problems have become common phenomenon in modern life. Emissions from the transport sectors (land-based transport, shipping, and aviation) significantly contribute to this effect. This is of particular relevance in view of comparatively large growth rates of these sectors. Climatically active components of transport emissions include: the long-lived greenhouse gas CO2; shortlived trace gases, in particular nitrogen oxides (NOx = NO + NO2), carbon monoxide (CO), and volatile organic compounds (VOC), which can induce changes in the concentration of the greenhouse gases ozone (O3) and methane (CH4); as well as aerosol particles (e.g., soot) and aerosol precursor gases (e.g., SO2 or the aforementioned NOx and VOC), which can cause important modifications of clouds and radiation.

scholarly journals A statistical approach for estimating representative emission rates of biogenic volatile organic compounds and their determination for 192 plant species/genera in China

2017 ◽  
Author(s):  
Lingyu Li ◽  
Yaqi Li ◽  
Shaodong Xie
Keyword(s):  
Plant Species ◽  
Statistical Approach ◽  
Emission Rate ◽  
Field Measurements ◽  
Gas Chromatography Mass Spectrometry ◽  
Emission Rates ◽  
Crop Species ◽  
Volatile Organic ◽  
Monoterpene Emission ◽  
High Emission

Abstract. To obtain more and accurate biogenic volatile organic compound (BVOC) emission rates for more plant species in China and further improve the accuracy of emission rates used in BVOC emission inventories, we conducted field measurements and developed a statistical approach for estimating representative emission rates. We performed field measurements of BVOC emissions from 50 plant species at nine locations in China using our established semi-static enclosure system. The emissions of 102 VOCs, including isoprene, α-pinene, β-pinene, and other VOC species, were analyzed with a custom-built online gas chromatography-mass spectrometry/flame ionization detector system. From the results, broadleaf trees were the greatest potential emitters of isoprene, while needle-leaf trees emitted more pinene. Shrubs had lower isoprene and pinene emission potentials, but higher emission potentials for other VOCs. Methyl methacrylate, isopropylbenzene, isopentane, acetone, ethane, propane, toluene, and xylene were the dominant species among other VOCs, probably with high emission intensities. Therefore, their emissions should be considered in future global and regional BVOC estimation studies. Next, we summarized our field measurements along with reported emission rates from China and abroad. The emission intensity categories were produced based on statistics, with more detailed categories, accurate emission rate intervals and representative rates compared to previous studies. The results showed that the BVOC emission intensities of plants displayed different categories, such as lowest, lower, low, moderate, high, higher, and highest. The isoprene emission rate intervals and representative rates were: lowest, 0.08–0.11 and 0.1 μg C gdw−1 h−1; lower, 0.9–1.3 and 1.0 μg C gdw−1 h−1; low, 5.2–6.5 and 5.8 μg C gdw−1 h−1; moderate, 13.1–15.3 and 14.4 μg C gdw−1 h−1; high, 31.1–37.0 and 33.6 μg C gdw−1 h−1; higher, 67.2–75.1 and 70.1 μg C gdw−1 h−1; and highest, 135.1–157.6 and 142.5 μg C gdw−1 h−1. The monoterpene emission rate intervals and representative rates were: lowest, 0.08–0.11 and 0.1 μg C gdw−1 h−1; lower, 0.17–0.22 and 0.2 μg C gdw−1 h−1; low, 0.5–0.7 and 0.6 μg C gdw−1 h−1; moderate, 1.2–1.5 and 1.4 μg C gdw−1 h−1; high, 2.8–3.3 and 3.0 μg C gdw−1 h−1; and higher, 11.1–14.9 and 12.6 μg C gdw−1 h−1. Using these established emission intervals, we determined the isoprene and monoterpene emission rates for 192 plant species/genera in China, including 30 dominant tree species, 149 shrub and grass genera, and 13 crop species. These estimations would be further improved by integrating larger quantities of rigorous field measurements from China in the future.

scholarly journals New foliage growth is a significant, unaccounted source for volatiles in boreal evergreen forests

2014 ◽  
Vol 11 (5) ◽  
pp. 1331-1344 ◽  
Author(s):  
J. Aalto ◽  
P. Kolari ◽  
P. Hari ◽  
V.-M. Kerminen ◽  
P. Schiestl-Aalto ◽  
...  
Keyword(s):  
Scots Pine ◽  
Emission Rate ◽  
Physiological State ◽  
Significant Proportion ◽  
Early Summer ◽  
Growth Stages ◽  
Emission Rates ◽  
Emission Pattern ◽  
Volatile Organic ◽  
Monoterpene Emission

Abstract. Estimates of volatile organic compound (VOC) emissions from forests are based on the assumption that foliage has a steady emission potential over its lifetime, and that emissions are mainly modified by short-term variations in light and temperature. However, in many field studies this has been challenged, and high emissions and atmospheric concentrations have been measured during periods of low biological activity, such as in springtime. We conducted measurements during three years, using an online gas-exchange monitoring system to observe volatile organic emissions from a mature (1 year-old) and a growing Scots pine shoot. The emission rates of organic vapors from vegetative buds of Scots pine during the dehardening and rapid shoot growth stages were one to two orders of magnitude higher than those from mature foliage; this difference decreased and finally disappeared when the new shoot was maturing in late summer. On average, the springtime monoterpene emission rate of the bud was about 500 times higher than that of the mature needles; during the most intensive needle elongation period, the monoterpene emission rate of the growing needles was 3.5 higher than that of the mature needles, and in September the monoterpene emission rate of the same years' needles was even lower (50%) than that of the previous years' needles. For other measured compounds (methanol, acetone and methylbutenol) the values were of the same order of magnitude, except before bud break in spring, when the emission rates of buds for those compounds were on average about 20–30 times higher than that of mature needles. During spring and early summer the buds and growing shoots are a strong source of several VOCs, and if they are not accounted for in emission modeling a significant proportion of the emissions – from a few percent to even half of the annual cumulative emissions – will remain concealed. The diurnal emission pattern of growing shoots differed from the diurnal cycle in temperature as well as from the diurnal emission pattern of mature shoots, which may be related to processes involved in shoot or needle elongation. Our findings imply that global estimations of monoterpene emission rates from forests are in need of revision, and that the physiological state of the plants should be taken into account when emissions of the reactive gases such as monoterpenes are estimated.

scholarly journals New foliage growth is a significant, unaccounted source for volatiles in boreal evergreen forests

2013 ◽  
Vol 10 (11) ◽  
pp. 18121-18150
Author(s):  
J. Aalto ◽  
P. Kolari ◽  
P. Hari ◽  
V.-M. Kerminen ◽  
P. Schiestl-Aalto ◽  
...  
Keyword(s):  
Scots Pine ◽  
Physiological State ◽  
Field Studies ◽  
Growth Stages ◽  
Emission Rates ◽  
Aerosol Formation ◽  
Emission Pattern ◽  
Evergreen Forests ◽  
Volatile Organic ◽  
Reactive Gases

Abstract. Estimates of volatile organic compound (VOC) emissions from forests are based on the assumption that foliage has a steady emission potential over its lifetime, and that emissions are mainly modified by short term variations in light and temperature. However, in many field studies this has been challenged, and high emissions and atmospheric concentrations have been measured during periods of low biological activity such as in springtime. We conducted measurements during three years, using an online gas-exchange monitoring system to observe volatile organic emissions from a mature (1 yr old) and a growing Scots pine shoot. The emission rates of organic vapours (monoterpenes, methyl butenol (MBO), acetone and methanol) from vegetative buds of Scots pine during the dehardening and rapid shoot growth stages were one to two orders of magnitude higher than those from mature foliage. The normally assumed temperature dependency was not sufficient to explain the variations in emission rates during spring. The diurnal emission pattern of growing shoots differed from the diurnal cycle in temperature as well as from the diurnal emission pattern of mature shoots, which may be related to processes involved in shoot or needle elongation. Our findings imply that global estimations of monoterpene emission rates from forests are in need of revision, and that the physiological state of the plants should be taken into account when emissions of the reactive gases such as monoterpenes are estimated. The significant interannual variation in emission rates, related to changes in plant metabolic activity, has important implications to the aerosol precursor concentrations and chemical reactions in atmosphere, and potentially offers an explanation for the frequent aerosol formation events in spring.

Scots pine provenance affects the emission rate and chemical composition of volatile organic compounds of forest floor

2018 ◽  
Vol 48 (11) ◽  
pp. 1373-1381 ◽  
Author(s):  
Minna Kivimäenpää ◽  
Juha-Matti Markkanen ◽  
Rajendra P. Ghimire ◽  
Toini Holopainen ◽  
Martti Vuorinen ◽  
...  
Keyword(s):  
Volatile Organic Compounds ◽  
Organic Compounds ◽  
Scots Pine ◽  
Forest Floor ◽  
Emission Rate ◽  
Plant Stress ◽  
Common Garden ◽  
Emission Rates ◽  
Volatile Organic ◽  
Growing Conditions

Scots pine (Pinus sylvestris L.) is an important source of biogenic volatile organic compounds (BVOCs) in the boreal zone. BVOC emission rate and profile affect air quality, climate forcing, plant stress tolerance, and thus the growing conditions of forests. BVOC emission profile of shoots and forest floor, as well as emission rates from forest floor, were studied in a latitudinal provenance experiment with 19-year-old Scots pine common garden in Central Finland. The provenances studied were Saaremaa (SAA, 58°22′), Korpilahti (KOR, 62°0′), Suomussalmi (SUO, 65°10′), and Muonio (MUO, 67°56′). A chemotype with high proportion of Δ-3-carene, terpinolene, sabinene, γ-terpinene, and α-terpinene was significantly more common for the southern SAA than the northern SUO and MUO provenances. A chemotype with high proportion of α-pinene, β-pinene, limonene, and myrcene was more common in the three northernmost provenances. The main compounds emitted by forest floor were α-pinene, Δ-3-carene, and camphene. Similarly to shoot emissions, forest floor emissions from SAA had highest proportion of Δ-3-carene. Average total VOC emission rate from forest floor was 50 μg·m−2·h−1 at the end of August. Total emission rates were 65% higher in KOR than in MUO. High emission rates were explained by the high amount of decomposing needle litter and low moss coverage.

scholarly journals Temperature and light dependence of the VOC emissions of Scots pine

2005 ◽  
Vol 5 (4) ◽  
pp. 989-998 ◽  
Author(s):  
V. Tarvainen ◽  
H. Hakola ◽  
H. Hellén ◽  
J. Bäck ◽  
P. Hari ◽  
...  
Keyword(s):  
Scots Pine ◽  
Late Summer ◽  
Early Spring ◽  
Early Summer ◽  
Emission Rates ◽  
Temperature Dependent ◽  
Forest Environment ◽  
Voc Emission ◽  
Monoterpene Emission ◽  
High Emission

Abstract. The volatile organic compound (VOC) emission rates of Scots pine (Pinus sylvestris L.) were measured from trees growing in a natural forest environment at two locations in Finland. The observed total VOC emission rates varied between 21 and 874 ngg-1 h-1 and 268 and 1670 ngg-1 h-1 in southern and northern Finland, respectively. A clear seasonal cycle was detected with high emission rates in early spring, a decrease of the emissions in late spring and early summer, high emissions again in late summer, and a gradual decrease in autumn. The main emitted compounds were Δ3-carene (southern Finland) and α- and β-pinene (northern Finland), with approximate relative contributions of 60–70% and 60–85% of the total observed monoterpene emission rates, respectively. Sesquiterpene (β-caryophyllene) and 2-methyl-3-buten-2-ol (MBO) emissions were initiated in early summer at both sites. The observed MBO emission rates were between 1 and 3.5% of the total monoterpene emission rates. The sesquiterpene emission rates varied between 2 and 5% of the total monoterpene emission rates in southern Finland, but were high (40%) in northern Finland in spring. Most of the measured emission rates were found to be well described by the temperature dependent emission algorithm. The calculated standard emission potentials were high in spring and early summer, decreased somewhat in late summer, and were high again towards autumn. The experimental coefficient β ranged from 0.025 to 0.19 (average 0.10) in southern Finland, with strongest temperature dependence in spring and weakest in late summer. Only the emission rates of 1,8-cineole were found to be both light and temperature dependent.

scholarly journals Odour, dust and non-methane volatile organic-compound emissions from tunnel-ventilated layer-chicken sheds: a case study of two farms

2013 ◽  
Vol 53 (12) ◽  
pp. 1309 ◽  
Author(s):  
Mark Dunlop ◽  
Zoran D. Ristovski ◽  
Erin Gallagher ◽  
Gavin Parcsi ◽  
Robin L. Modini ◽  
...  
Keyword(s):  
Dust Emission ◽  
Ventilation Rate ◽  
Gas Chromatography Mass Spectrometry ◽  
Emission Rates ◽  
Layer Chicken ◽  
Volatile Organic ◽  
Different Seasons ◽  
Odour Emissions ◽  
Cleaning Cycle ◽  
Study Sites

An observational study was undertaken to measure odour and dust (PM10 and PM2.5) emission rates and identify non-methane volatile organic compounds (NMVOCs) and odorants in the exhaust air from two tunnel-ventilated layer-chicken sheds that were configured with multi-tiered cages and manure belts. The study sites were located in south-eastern Queensland and the West Gippsland region of Victoria, Australia. Samples were collected in summer and winter on sequential days across the manure-belt cleaning cycle. Odour emissions ranged from 58 to 512 ou/s per 1000 birds (0.03–0.27 ou/s.kg) and dust emission rates ranged 0.014–0.184 mg/s per 1000 birds for PM10 and 0.001–0.190 mg/s per 1000 birds for PM2.5. Twenty NMVOCs were identified, including three that were also identified as odorants using thermal desorption–gas chromatography–mass spectrometry/olfactometry analysis. Odour emission rates were observed to vary with the amount of manure accumulation on the manure belts, being lowest 2–4 days after removing manure. Odour emission rates were also observed to vary with diurnal and seasonal changes in ventilation rate. Dust emissions were observed to increase with ventilation rate but not with manure accumulation. Some NMVOCs were identified at both farms and in different seasons whereas others were observed only at one farm or in one season, indicating that odorant composition was influenced by farm-specific practices and season.

scholarly journals Sensitivity of managed boreal forests in Finland to climate change, with implications for adaptive management

2007 ◽  
Vol 363 (1501) ◽  
pp. 2339-2349 ◽  
Author(s):  
Seppo Kellomäki ◽  
Heli Peltola ◽  
Tuula Nuutinen ◽  
Kari T Korhonen ◽  
Harri Strandman
Keyword(s):  
Climate Change ◽  
Norway Spruce ◽  
Scots Pine ◽  
Boreal Forests ◽  
Forest Growth ◽  
Forest Land ◽  
Forest Zone ◽  
The North ◽  
Northern Forests ◽  
Climate Change Model

This study investigated the sensitivity of managed boreal forests to climate change, with consequent needs to adapt the management to climate change. Model simulations representing the Finnish territory between 60 and 70° N showed that climate change may substantially change the dynamics of managed boreal forests in northern Europe. This is especially probable at the northern and southern edges of this forest zone. In the north, forest growth may increase, but the special features of northern forests may be diminished. In the south, climate change may create a suboptimal environment for Norway spruce. Dominance of Scots pine may increase on less fertile sites currently occupied by Norway spruce. Birches may compete with Scots pine even in these sites and the dominance of birches may increase. These changes may reduce the total forest growth locally but, over the whole of Finland, total forest growth may increase by 44%, with an increase of 82% in the potential cutting drain. The choice of appropriate species and reduced rotation length may sustain the productivity of forest land under climate change.

scholarly journals Prediction of photosynthesis in Scots pine ecosystems across Europe by a needle-level theory

2018 ◽  
Vol 18 (18) ◽  
pp. 13321-13328
Author(s):  
Pertti Hari ◽  
Steffen Noe ◽  
Sigrid Dengel ◽  
Jan Elbers ◽  
Bert Gielen ◽  
...  
Keyword(s):  
Scots Pine ◽  
Boreal Forests ◽  
Co2 Flux ◽  
Field Studies ◽  
Co2 Assimilation ◽  
Co2 Fluxes ◽  
New Era ◽  
Evergreen Forests ◽  
Transition Times

Abstract. Photosynthesis provides carbon for the synthesis of macromolecules to construct cells during growth. This is the basis for the key role of photosynthesis in the carbon dynamics of ecosystems and in the biogenic CO2 assimilation. The development of eddy-covariance (EC) measurements for ecosystem CO2 fluxes started a new era in the field studies of photosynthesis. However, the interpretation of the very variable CO2 fluxes in evergreen forests has been problematic especially in transition times such as the spring and autumn. We apply two theoretical needle-level equations that connect the variation in the light intensity, stomatal action and the annual metabolic cycle of photosynthesis. We then use these equations to predict the photosynthetic CO2 flux in five Scots pine stands located from the northern timberline to Central Europe. Our result has strong implications for our conceptual understanding of the effects of the global change on the processes in boreal forests, especially of the changes in the metabolic annual cycle of photosynthesis.

Sign in / Sign up

Export Citation Format

Share Document