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- Research Article
3
- 10.3390/soilsystems8020064
- Jun 13, 2024
- Soil Systems
- Daizy Bharti + 3 more
This study represents the first investigation of soil ciliate diversity and community structure in the Marche region, Italy, encompassing both natural sites and agro-ecosystems. The main aims were (i) to assess the ability of ciliates to discriminate between different types of land uses, i.e., arable lands and possible farming management practices [organic (ORG) vs. conventional (CON)], and forest (FOR) sites; and (ii) to investigate the relationships among ciliate communities and abiotic parameters at the studied sites. Soil samples were collected twice from 10 sites (5 forest (FOR) (natural soils) and 5 arable lands under different agricultural management systems (3 ORG (minimum tillage) and 2 CON (sod seeding)). Ciliate communities were studied using qualitative (non-flooded Petri dish) and quantitative methods (ciliate counts from permanent slides). Soil chemical–physical (texture, CEC, N, OM, C/N) parameters were also measured. Qualitative ciliate analysis allowed us to identify a total of 59 species representing 33 genera, 20 families, 13 orders, and 7 classes. ORG sites were the richest in species followed by CON and FOR. Multivariate analysis showed statistically significant differences between natural sites (FOR) and agricultural sites, and between ORG and CON management farming systems. CCA analysis revealed a positive correlation between the ciliate species and silt, clay, and pH in ORG sites, and sand, organic carbon, organic matter, total nitrogen, C/N ratio, and CEC (cation exchange capacity) in FOR sites, suggesting the significance of these parameters in shaping the ciliate communities. Altogether, these results showed the bioindicative potential of ciliate communities in discriminating between natural sites (FOR) and arable lands, and their capacity to discriminate, at least preliminarily, between different soil management systems (ORG vs. CON). Furthermore, this study highlights the high diversity of soil ciliates and their response to habitat variability.
- Research Article
6
- 10.3390/plants13101384
- May 16, 2024
- Plants
- Hongyuan Zhang + 4 more
Quantitative evaluation of the effects of diverse greenhouse vegetable production systems (GVPS) on vegetable yield, soil water consumption, and nitrogen (N) fates could provide a scientific basis for identifying optimum water and fertilizer management practices for GVPS. This research was conducted from 2013 to 2015 in a greenhouse vegetable field in Quzhou County, North China. Three production systems were designed: conventional (CON), integrated (INT), and organic (ORG) systems. The WHCNS-Veg model was employed for simulating vegetable growth, water dynamics, and fates of N, as well as water and N use efficiencies (WUE and NUE) for four continuous growing seasons. The simulation results revealed that nitrate leaching and gaseous N emissions constituted the predominant N loss within GVPS, which separately accounted for 11.5-59.4% and 6.0-21.1% of the N outputs. The order of vegetable yield, N uptake, WUE, and NUE under different production systems was ORG > INT > CON, while the order of nitrate leaching and gaseous N loss was CON > INT > ORG. Compared to CON, ORG exhibited a significant increase in yield, N uptake, WUE, and NUE by 24.6%, 24.2%, 26.1%, and 89.7%, respectively, alongside notable reductions in nitrate leaching and gaseous N loss by 67.7% and 63.2%, respectively. The ORG system should be recommended to local farmers.
- Research Article
1
- 10.1111/wre.12632
- May 9, 2024
- Weed Research
- Bàrbara Baraibar + 1 more
Abstract The resource pool diversity hypothesis (RPDH) posits that organic systems that include diverse crop rotations, green manure and organic fertilizers have a greater diversity of resource pools that can alleviate weed–crop competition compared to conventional systems. To test the RPDH, wheat (Triticum aestivum) and wild oats (Avena sterilis) in winter, and maize (Zea mays) and Palmer amaranth (Amaranthus palmeri) in summer, were grown in pots in soils from organic (ORG) and conventional (CONV) fields, with contrasting number of estimated resource pools. A replacement series design with proportions of crop: weed of 0:1, 0.25:0.75, 0.5:0.5, 0.75:0.25 and 1:0 was used. Half of the pots received an organic‐mineral fertilizer (F) and the other half did not (NF). Aerial biomass of all plants was measured. Relative Crowding Coefficient (RCC) and the product of RCC (RCCP) for each crop and weed biomass were estimated by modelling the biomass across crop: weed proportions. RCCP larger than one was used as an indicator of overyielding. In the winter experiment, wheat always outcompeted wild oats and we did not detect overyielding across fields with different number of pools, system or fertilizer. In the summer experiment, we found overyielding in ORG NF fields. Functionally different species like maize and Palmer amaranth may have been extracting nutrients from diverse pools in organic NF fields whereas with the addition of fertilizer, Palmer amaranth outcompeted maize. Biomass of monoculture crop and weed in both experiments were positively correlated with number of estimated pools, even if none of the competition indexes were. Our results provide some support for the RPHD in species that are functionally different but also question the definition and nature of the nutrient pools, as well as emphasize the need for more research in the area.
- Research Article
3
- 10.1139/cjps-2023-0177
- Apr 12, 2024
- Canadian Journal of Plant Science
- S.K Curtis + 4 more
Information is required to understand how novel biodiversity strategies can improve cropping system resilience to climate change. A “business as usual” (BAU) rotation (wheat–canola–wheat–soybean) was compared with a “warm-season crop” (WS) rotation (corn–sunflower–dry bean–canola); a “biodiverse” (BD) rotation (fall rye with cover crop– corn/soybean intercrop—pea/canola intercrop–green fallow mixture); a “perennial grain” (Kernza) rotation (Kernza grain intermediate wheatgrass); and an organic (ORG) rotation (millet-green fallow mixture-wheat). Drought conditions prevailed in both study years. The BAU rotation had the lowest average yield (1821 kg ha−1 compared with 2533 and 3083 kg ha−1 for the BD and WS rotations, respectively), less post-harvest residual biomass, and a lower net return than the WS rotation. The WS rotation was limited by herbicide-resistant weeds in dry beans. Kernza seed yield was five times lower than for spring wheat. ORG wheat yielded the same as other wheat and had a higher net return. Live roots days, a measure of soil health potential, were 95 for the BAU rotation and 174 and 113 for the BD and WS rotations, respectively; the most were recorded for Kernza (365). Seasonal crop growth duration was increased by including Kernza and fall rye for early season growth, and corn, sunflower, a corn–soybean intercrop, a cover crop, and fall-seeded rye for late season growth. WS and BD rotations outperformed the BAU rotation and the BD system accomplished this with half the N fertilizer. Results demonstrate the potential of biodiverse rotations; barriers to their adoption should be addressed.
- Research Article
3
- 10.3390/foods13081165
- Apr 11, 2024
- Foods
- Xing Liu + 8 more
Seasonal (temporal) variations can influence the δ13C, δ2H, δ18O, and δ15N values and nutrient composition of organic (ORG), green (GRE), and conventional (CON) vegetables with a short growth cycle. Stable isotope ratio mass spectrometry (IRMS) and near-infrared spectroscopy (NIRS) combined with the partial least squares-discriminant analysis (PLS-DA) method were used to investigate seasonal effects on the identification of ORG, GRE, and CON Brassica chinensis L. samples (BCs). The results showed that δ15N values had significant differences among the three cultivation methods and that δ13C, δ2H, and δ18O values were significantly higher in winter and spring and lower in summer. The NIR spectra were relatively clustered across seasons. Neither IRMS-PLS-DA nor NIRS-PLS-DA could effectively identify all BC cultivation methods due to seasonal effects, while IRMS-NIRS-PLS-DA combined with Norris smoothing and derivative pretreatment had better predictive abilities, with an 89.80% accuracy for ORG and BCs, 88.89% for ORG and GRE BCs, and 75.00% for GRE and CON BCs. The IRMS-NIRS-PLS-DA provided an effective and robust method to identify BC cultivation methods, integrating multi-seasonal differences.
- Research Article
18
- 10.3390/app14051886
- Feb 25, 2024
- Applied Sciences
- Katarzyna Wysocka + 3 more
The quality of flour is influenced by various factors including genotype, environmental and agronomic conditions, post-harvest grain storage, and milling technology. Currently, the EU focuses on reducing mineral fertilization and promoting less intensive agrotechnology (organic and integrated farming). This research aimed to assess the baking value of flour obtained from four spring wheat cultivars cultivated in three farming systems: organic (ORG), integrated (INT), and conventional (CONV). The wheat grains were sourced from a three-year field experiment (2019–2021) conducted at IUNG-PIB in Pulawy, Poland. Results indicate that the CONV generally yielded more favourable qualitative parameters for the flour, including significantly higher protein content, wet gluten, falling number, and farinographic characteristics such as dough development, stability time, and quality number. Nevertheless, most flours from the ORG system met the quality requirements for the baking industry, showing adequate protein content, wet gluten, and falling number. However, flours from the INT system stood out due to significantly higher water absorption, resulting in increased dough and bread yield. Additionally, bread baked from these flours exhibited a significantly higher bread volume. In sensory evaluation, bread from CONV flours received the highest scores, although the differences in the overall acceptability were not significant.
- Research Article
6
- 10.1016/j.psj.2024.103522
- Feb 2, 2024
- Poultry Science
- Reza Bakhshalinejad + 2 more
Comparative efficacy of hydroxychloride (HC) and organic (OR) sources of Zn, Cu and Mn on performance of broiler breeders (BB) between 42 and 63 weeks of age (WOA) was investigated. A total of 408 ♀ Ross 708 and 48 ♂ Yield Plus cockerels were placed in pens (17 ♀ and 2 ♂) housed in 2 rooms (12 pens/room) and allocated to one of 2 diets in a completely randomized block design (n=12). The diets had similar nutrient specifications but differed in Zn, Cu, and Mn sources: 1) HO, a blend of 80% HC and 20% OR sources, and 2) OR, 100% OR sources. Birds were fed and managed according to breeder guidelines. The egg count was recorded daily and categorized as normal or abnormal. Egg yolk color, albumen height, Haugh unit, eggshell thickness, and eggshell breaking strength were assessed every 4 wk. Individual hen body weight (BW) was recorded at 5-wk intervals to determine BW uniformity. At 52 and 63 WOA, the eggs and excreta samples were collected. At the end of the trial, 4 hens per pen were bled for plasma concentration of trace minerals and organs (liver, gizzard, spleen, kidney, and thymus) weight. There were no interactions between source and age on any parameters (P > 0.05). There were no main effects of source on egg production, eggshell quality, BW, and organs weight (P > 0.05). Hens fed HO diets had darker yolk compared to those fed OR diets (P = 0.014). The concentration of Zn in the eggs of OR BB was higher (P = 0.022) than for HO birds. However, there were no dietary effects on the concentration of trace minerals in the egg, plasma, and excreta (P > 0.05). The results indicated that a mixture of HC and O as sources for Zn, Cu, and Mn was as effective as OR sources in supporting egg production, egg quality, and trace mineral utilization in broiler breeders.
- Research Article
21
- 10.1029/2023jd039902
- Jan 19, 2024
- Journal of Geophysical Research: Atmospheres
- J L Hand + 2 more
Abstract Large reductions in anthropogenic emissions of particulate matter and its precursor emissions have occurred since the enactment of the Clean Air Act Amendments of 1990. The Interagency Monitoring of Protected Visual Environments network has measured PM2.5 gravimetric mass (mass of particles with aerodynamic diameters less than 2.5 μm, also referred to here as fine mass, “FM”) and speciated PM2.5 aerosol composition at remote sites since 1988. Measured species include inorganic anions such as sulfate, nitrate, and chloride, carbonaceous aerosols such as organic (OC) and elemental carbon (EC), and elemental concentrations used to estimate fine dust (FD). Trends in seasonal and annual mean mass concentrations were calculated from 2000 through 2021, a period that includes the largest reductions in emissions. On average, annual mean FM at remote sites in the continental United States has decreased at a rate of −1.8% yr−1. This reduction is largely due to annual mean trends in sulfate (−6.1% yr−1), nitrate (−2.7% yr−1), EC (−2.2% yr−1), FD (−1.3% yr−1), and OC (−0.9% yr−1), although the OC annual mean trend was insignificant. Seasonal and regional mean FM trends varied significantly, with strong reductions in the East in all seasons due to sulfate reductions, and flat and insignificant trends in summer and fall in the West due to the influence of biomass burning emissions on OC trends. Evaluating regional and seasonal mean trends in aerosol composition helps identify sources that continue to adversely impact air quality and hinder progress in FM reductions due to successful regulatory activity.
- Research Article
- 10.59515/rma.2023.v44.i2.15
- Dec 20, 2023
- Range Management and Agroforestry
- Dhandayuthapani Udhayanandhini + 4 more
A study was conducted to evaluate the impact of organic and conventional production system on fodder cowpea growth and soil health. This study was conducted in a farmers field of Erode, Tamil Nadu in a randomized block design with three replications. For the study, six farmers' fields involving organic (ORG) practices and one conventional (CON) production system were selected. Soil and plant samples were collected at the time of harvest and analyzed for growth, and soil health parameters. The results revealed that significant differences were found in the growth parameters of fodder cowpea among the organic and conventional production system. The analyzed chemical properties ., soil reaction, electrical conductivity viz(EC), macro nutrients, and biological indicators ., soil organic carbon (SOC), organic matter (SOM), vizmicrobial biomass carbon (MBC), culturable microbes, and yield were found to be higher in organically managed soils than the conventional farming method
- Research Article
7
- 10.1016/j.foohum.2023.11.006
- Nov 22, 2023
- Food and Humanity
- A Annapurna Reddy + 4 more
Nutritional compilation of commonly consumed organic and conventional fruits and vegetables from India
- Research Article
- 10.31857/s0002351523060123
- Nov 1, 2023
- Известия Российской академии наук. Физика атмосферы и океана
- S S Vlasenko + 3 more
The results of back-trajectory analysis of nine-year (2013–2021) measurements of organic (OC) and elemental (EC) aerosol carbon concentrations made at the atmospheric monitoring station near St. Petersburg (Peterhof, 59.88° N, 29.83° E) are presented. The spatial location of sources was estimated by the concentration weighted trajectory method (CWT) in the geographic area 16°–44° E × 48°–68° N. The obtained data allow us to identify the territories with the strongest organic and elemental carbon emissions and to estimate the seasonal variability of these emissions. In particular, the obtained estimates show that the most intense sources of organic and elemental aerosol carbon in the studied region are located in the Volga-Oka interfluve and on the adjacent territories. It is demonstrated that linear regression coefficients between CWT function values for organic and elemental carbon differ for different regions and seasons and may indicate the prevailing type of sources of carbon-containing aerosol particles.
- Research Article
5
- 10.3389/fagro.2023.1211755
- Sep 25, 2023
- Frontiers in Agronomy
- Darshika Wickramasinghe + 4 more
Integrated weed control strategies are essential for organic and integrated nutrient management, where both systems are progressing with a fundamental of zero or minimum synthetic chemical cultivations. For optimizing the outcome of weed management, a better understanding of the weed dynamic is needed. Especially, with the absence of herbicides, weeds are expected to be controlled by the system itself, during the transition period under rice-based crop rotation systems. This study was conducted to estimate the weed abundance, growth, and composition during the transitional period with conventional (CONV), integrated (INT), and organic (ORG) nutrient management under four crop diversification intensities in a dry zone of Sri Lanka. Monocrop rice and a rice-maize rotation were the starting point. After 1 year, the diversification intensity was increased by adding interseason sunnhemp (rice-sunnhemp-rice and rice-sunnhemp-maize). Weed density and weed biomass were measured at 20 DAS and 60 DAS intervals. Weed density was higher in ORG during the early growth stages of monocrop rice rotation in the 1st cycle, and monocrop rice and rice-sunnhemp-rice rotation in the 2nd cycle while didn’t show any changes during the later growth stage of all systems in both cycles. The total weed biomass in ORG increased with increasing crop diversification. Overall, crop rotation in INT reported the lowest weed density and biomass after two cycles. In the CONV with rice-sunnhemp-maize rotation, weed biomass had declined, while in ORG grass biomass decreased only in sunnhemp cultivated rotations. Overall, INT was the best for weed suppression irrespective of crop rotation intensities. Monoculture with rice in the INT was able to suppress weed more effectively than rice-maize rotation.
- Research Article
1
- 10.3390/vetsci10080511
- Aug 8, 2023
- Veterinary Sciences
- Jesse O Fulton + 6 more
To determine the influence of the source of gestational and postnatal Cu and Zn supplementation on cow and calf performance, cows (n = 287) were assigned to one of the following two treatments: (1) inorganic (INORG) treatment, in which cows were supplemented with 15 mg of Cu (as CuSO4) and 15 mg of Zn (as ZnSO4) per kg of diet DM, or (2) organic (ORG) treatment, in which cows were supplemented with 15 mg of Cu (as Cu proteinate; Bioplex Cu, Alltech, Inc., Nicholasville, KY, USA) and 15 mg of Zn (as Zn proteinate; Bioplex Zn, Alltech, Inc., Nicholasville, KY, USA) per kg of diet DM. The treatments were initiated prior to breeding and continued throughout gestation until weaning. Liver biopsies were collected for analysis of mineral content. Cow body condition score (BCS), body weight (BW), pregnancy data, calf weaning weight (WW), and antibody response of the calves were recorded. The cows receiving the INORG treatment had a greater BW (p < 0.05) and BCS (p < 0.01) at breeding in Year 2, while the cows on the ORG treatment had a greater (p < 0.05) BW at weaning in Year 2. The cows that received the ORG mineral had improved (p < 0.05) conception rates in Year 1. The calves receiving the ORG treatment had heavier (p < 0.05) 205-day adjusted WWs.
- Research Article
2
- 10.2478/plua-2023-0010
- Aug 1, 2023
- Rural Sustainability Research
- Stefanija Sabunevica + 1 more
Abstract In recent years, the demand for organic fermented dairy products has been growing. Lactic acid bacteria (LAB) are of major interest in the food industry due to their ability to form the quality and functionality of fermented products. A significantly higher LAB cell count is presented in organic (ORG) fermented products such as yoghurt and kefir, than their conventional (CONV) counterparts. There is still a lack of information on the possible explanation and evidence of ORG milk as a better medium for LAB growth. The aim of the present review is to summarise the results of research articles on the milk compounds and their effect on LAB growth, and to identify differences between ORG and CONV milk that may provide a plausible explanation for their influence on LAB growth in ORG milk. The monographic method was used in this study. According to the previous research, significant differences were established in a content and range of carbohydrates, nitrogen sources, fats, macroelements and microelements, as well bioactive compounds in ORG and CONV milk. The composition of ORG milk may have potential benefits for the development of LAB due to the higher concentration of peptides and long-chain polyunsaturated fatty acids in it.
- Research Article
3
- 10.1088/1755-1315/1199/1/012023
- Jul 1, 2023
- IOP Conference Series: Earth and Environmental Science
- Rahmi Mulia Putri + 4 more
In this study, the distribution of PMs and their carbonaceous components, including organic (OC) and elemental carbon (EC) was evaluated to determine how much carbon profiles within ambient aerosol differ between four different sites in Medan city or (roadside (RS), school environment (SE), industrial area (IA), and volcano area (VA). Samples were taken by using ambient nano sampler (ANS) from February 19th to March 12th, 2019. Carbon analyser followed by IMPROVE_TOR methods was used to evaluate the carbonous component in all sites. Overall, OC is the primary carbon component, comprising more than 60% of all sites. Regarding particle size, the largest OC content was recorded in PM0.5-1 across all locations, suggesting that this particle size should be the primary focus of future evaluations of the consequences of biomass burning. The concentration of soot-EC dropped with the increase in particle size, since it was commonly influenced by vehicle emissions, which typically generated ultrafine and fine particles. PM0.1 has the greatest concentration of soot-EC. Due to their proximity to the city’s busiest thoroughfare, RS and SE sites had a larger soot-EC proportion than the two remaining sites (IA and VA) (Sisingamangaraja Street).
- Research Article
11
- 10.1016/j.scitotenv.2023.164527
- May 31, 2023
- Science of the Total Environment
- Saliou Mbengue + 10 more
To prevent the fast spread of COVID-19, worldwide restrictions have been put in place, leading to a reduction in emissions from most anthropogenic sources. In this study, the impact of COVID-19 lockdowns on elemental (EC) and organic (OC) carbon was explored at a European rural background site combining different approaches: − “Horizontal approach (HA)” consists of comparing concentrations of pollutants measured at 4 m a.g.l. during pre-COVID period (2017–2019) to those measured during COVID period (2020-2021); − “Vertical approach (VA)” consists of inspecting the relationship between OC and EC measured at 4 m and those on top (230 m) of a 250 m-tall tower in Czech Republic. The HA showed that the lockdowns did not systematically result in lower concentrations of both carbonaceous fractions unlike NO2 (25 to 36 % lower) and SO2 (10 to 45 % lower). EC was generally lower during the lockdowns (up to 35 %), likely attributed to the traffic restrictions whereas increased OC (up to 50 %) could be attributed to enhanced emissions from the domestic heating and biomass burning during this stay-home period, but also to the enhanced concentration of SOC (up to 98 %). EC and OC were generally higher at 4 m suggesting a greater influence of local sources near the surface. Interestingly, the VA revealed a significantly enhanced correlation between EC and OC measured at 4 m and those at 230 m (R values up to 0.88 and 0.70 during lockdown 1 and 2, respectively), suggesting a stronger influence of aged and long distance transported aerosols during the lockdowns. This study reveals that lockdowns did not necessarily affect aerosol absolute concentrations but it certainly influenced their vertical distribution. Therefore, analyzing the vertical distribution can allow a better characterization of aerosol properties and sources at rural background sites, especially during a period of significantly reduced human activities.
- Research Article
4
- 10.3168/jds.2022-22730
- May 8, 2023
- Journal of Dairy Science
- C.L Manuelian + 5 more
Comparison of chemical composition of organic and conventional Italian cheeses from parallel production
- Research Article
16
- 10.1016/j.agee.2023.108442
- Feb 28, 2023
- Agriculture, Ecosystems & Environment
- Summer R.A Lockhart + 4 more
Soil CO2 in organic and no-till agroecosystems
- Research Article
71
- 10.3390/plants12051022
- Feb 23, 2023
- Plants
- Katarzyna Mitura + 4 more
Genotype (cultivar), soil and climatic conditions, the agrotechnology used, and the interaction of the factors mentioned play a key role in the yield and quality of wheat grain. Currently, the European Union recommends the balanced use of mineral fertilisers and plant protection products in agricultural production (integrated production) or the use of only natural production methods (organic production). The aim of the study was to compare the yield and grain quality of four spring common wheat cultivars Harenda, Kandela, Mandaryna, and Serenada, grown under three farming systems: organic (ORG), integrated (INT), and conventional (CONV). A three-year field experiment was conducted between 2019 and 2021 at the Osiny Experimental Station (Poland, 51°27' N; 22°2' E). The results showed that significantly the highest wheat grain yield (GY) was obtained at INT, while the lowest was obtained at ORG. The physicochemical and rheological characteristics of the grain were significantly influenced by the cultivar factor and, with the exception of 1000 grain weight (TGW) and ash content (AC), by the farming system. There were also numerous interactions between the cultivar and farming systems, which suggests different performances of cultivars and, in fact, that some cultivars are better or worse suited to different production systems. The exceptions were protein content (PC) and falling number (FN), which were significantly highest in grain with CONV and lowest in grain with ORG farming systems.
- Research Article
3
- 10.3390/atmos14020371
- Feb 13, 2023
- Atmosphere
- Mattia Borelli + 8 more
Different Light-Absorbing Snow Impurities (LASI) can deposit on snow- and ice-covered surfaces. These particles are able to decrease snow and ice albedo and trigger positive albedo feedback. The aim of this work was to develop a new method to quantify the carbonaceous fractions that are present in snow and ice samples that contribute significantly to their darkening. Currently, in the literature, there is an absence of a unified and accepted method to perform these studies. To set up the method proposed here, snow samples were collected at two Italian locations, Claviere and Val di Pejo (Northern Italy). The samples were analyzed using two main techniques, Total Organic Carbon analysis (TOC analysis) and Thermal Optical analysis in Transmittance mode (TOT), which enabled the speciation of the carbonaceous fraction into organic (OC), inorganic (IC), and elemental carbon (EC), and further into the soluble and insoluble parts. The results highlighted a correlation between the nature of the sample (i.e., location, age, and exposure of the snow) and the experimental results, giving validity to the method. For example, the abundant presence of terrigenous constituents was reflected in high amounts of insoluble IC. Moreover, due to the trend between insoluble IC and Elemental Carbon (EC), the role of IC in TOT analysis was investigated. Indeed, IC turned out to be an interfering agent, suggesting that the two techniques (TOC analysis and TOT) are complementary and therefore need to be used in parallel when performing these studies. Finally, the results obtained indicate that the newly proposed method is suitable for studying the carbonaceous fractions in snow samples.