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The paper presents the results of studies on the annual biomass of above-ground parts of aquatic and rush vegetation communities growing along the banks and bed of the Lyna River within the administrative boundaries of Olsztyn tow...
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The paper presents the results of studies on the annual biomass of above-ground parts of aquatic and rush vegetation communities growing along the banks and bed of the Lyna River within the administrative boundaries of Olsztyn town. The lowest levels of fresh and dry biomass were found for the lobes of Lemno-Spirodeletum, and the highest were recorded in the lobes of Typhetum latifoliae and Phragmitetum.
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This paper focuses on optical and microphysical properties of long-range transported biomass burning (BB) aerosols and their variation with atmospheric evolution (ageing), as observed by a multiwavelength Raman lidar, part of EARL...
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This paper focuses on optical and microphysical properties of long-range transported biomass burning (BB) aerosols and their variation with atmospheric evolution (ageing), as observed by a multiwavelength Raman lidar, part of EARLINET (European Aerosol LIdar NETwork). Chemical analysis of the atmospheric aerosol was done using a colocated aerosol mass spectrometer (AMS). One relevant optical parameter for the ageing process is the ?ngstr?m exponent. In our study, we find that it decreases from 2 for fresh to 1.4-0.5 for aged smoke particles. The ratio of lidar (extinction-to-backscatter) ratios (LR _(532)/LR_(355)) changes rapidly from values <1 for fresh to >1 for aged particles. The imaginary part of the refractive index is the most sensitive microphysical parameter. It decreases sharply from 0.05 to less than 0.01 for fresh and aged smoke particles, respectively. Singlescattering albedo (SSA) varies from 0.74 to 0.98 depending on aerosol age and source. The AMS was used to measure the marker ions of wood-burning particles during 2 days of measurements when the meteorological conditions favored the downward mixing of aerosols from lofted layers. Particle size distribution and particle effective radius from both AMS and lidar are similar, i.e., particle effective radii were approximately 0.27 μm for fresh BB aerosol particles. Microphysical aerosol properties from inversion of the lidar data agree with similar studies carried out in different regions on the globe. Our study shows that the ?ngstr?m exponent LR_(532)/LR_(355) and the imaginary part of the refractive index can be used to clearly distinguish between fresh and aged smoke particles.
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Fourteen accessions of Cynara cardunculus were compared with the aim to evaluate the fresh biomass production and its partition, aiming at its potential use for industrial purposes. At anthesis stage, when plants have the maximum ...
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Fourteen accessions of Cynara cardunculus were compared with the aim to evaluate the fresh biomass production and its partition, aiming at its potential use for industrial purposes. At anthesis stage, when plants have the maximum vegetative development, stalks, leaves and capitula were weighed separately. The percentage of dry matter per gram of fresh biomass was also calculated. The first capitulum components of each plant: bracts, flowers and remnant receptacle were also weighed separately. The total fresh biomass ranged between 1188 and 3235 g/plant, with variable values within each botanical variety, whereas the partition of the aboveground biomass was strongly affected by botanical variety. In both cardoons varieties, the percentage of dry matter ranged between 30 and 35% for all components of aboveground biomass, whereas in globe artichoke values ranged between 20% for capitula and 40% for leaves. Regarding capitula components, receptacle weight was of greatest importance in globe artichoke and cultivated cardoon. In wild cardoon flowers weight was more important than the other components. Results suggest that Cynara cardunculus var. scolymus and C. cardundulus var. cardunculus, might be considered as double purpose crops if after the capitula (in globe artichoke) or leaves (in cardoon) harvest, the fresh matter remaining is artificially dried and cut. On the other hand, Cynara cardunculus var. sylvestris, might be incorporated into the culture system as an industry or energy crop due the low inputs management that it requires, its adaptability to the local conditions and its aboveground biomass production.Digital Object Identifier http://dx.doi.org/10.1016/j.indcrop.2011.12.028
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Experiments were performed in a thermogravimetric analyser to understand the effects of initial moisture of biomass on its pyrolysis and kinetics. Scanning electron microscopy, X-ray diffractometry and Fourier transform infrared s...
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Experiments were performed in a thermogravimetric analyser to understand the effects of initial moisture of biomass on its pyrolysis and kinetics. Scanning electron microscopy, X-ray diffractometry and Fourier transform infrared spectroscopy were employed to determine the effects of the initial moisture of grass on the char structure. Kinetic parameters were obtained by applying Flynn-Wall-Ozawa method. The results indicate that the pyrolysis characteristic temperatures and the char residue decrease with greater initial moisture of grass. The results of char analysis show that the chars' cell walls become thinner, and the fractal dimension increases, and the chars' microcrystalline became smaller and many functional groups' band peaks of chars become smaller and even disappear with the initial moisture increasing. The activation energy as a function of the conversion reveals the multi-step nature of the fresh-grass devolatilisation. The activation energy reduces about 30kJ mol~(-1) when the initial moisture increases from 4.52% to 44.17%.
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In this paper, characterization of the optical and microphysical properties of extremely fresh biomass burning aerosol is presented. This work aims to characterize, for the first time to our knowledge, freshly formed smoke particl...
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In this paper, characterization of the optical and microphysical properties of extremely fresh biomass burning aerosol is presented. This work aims to characterize, for the first time to our knowledge, freshly formed smoke particles observed only a few minutes after they were emitted from a nearby forest fire. The smoke particles were detected by combining passive (sun-photometer) and active (Raman lidar) techniques. On 14 August 2021, an EARLINET (European Aerosol Research Lidar Network) multi-wavelength Raman lidar and a co-located AERONET sun-photometer in Potenza, South Italy, observed an extremely fresh smoke plume. The lidar measurements, carried out from 2227 to 0216 UTC, revealed a thick biomass burning layer below 2.7 km. The particle depolarization ratio at 532 nm was 0.025, and lidar ratios at 355 and 532 nm were, respectively, 40 and 38 sr. The mean value of the ?ngstr?m exponent was 1.5. The derived size distribution was bimodal with a peak at 0.13 μm, an effective radius mean value of 0.15 μm, and a single scattering albedo of 0.96 at all wavelengths. The real part of the refractive index was 1.58 and the imaginary was 0.006. The AERONET measurements at 534 UTC confirmed the lidar measurements.
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Abstract Studies examining the role of abiotic variables on fructification sequences of ectomycorrhizal symbionts (boletes), the extent and direction of these effects are quite rare in Africa. In the current study, we assessed the...
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Abstract Studies examining the role of abiotic variables on fructification sequences of ectomycorrhizal symbionts (boletes), the extent and direction of these effects are quite rare in Africa. In the current study, we assessed the effects of microclimate on the distribution and productivity of boletes in Benin. Nine permanent plots of 2500?m2 each split into 25?subplots of 100?m2 were installed in three different vegetation types. The first vegetation type is dominated by Isoberlinia doka, the second by Isoberlinia tomentosa and the third by Uapaca togoensis. Abiotic variables, including soil temperature, air temperature, air relative humidity and soil moisture, were recorded every 30?min from June to October. Each plot was surveyed twice a week during the mushroom season over 3?years (2015, 2016 and 2017) to record the abundance and the fresh biomass. The effects of microclimate on boletes productivity were evaluated using generalised linear mixed models in R. Boletes give the largest natural production in July and the lowest in October. Only soil moisture has a significant negative influence on the abundance (p?>?0.05). The fruiting periods of boletes are known according to the variability of the microclimatic parameters and the vegetation.
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Release and evaluation studies of the Brazil population of Cyrtobagous salviniae on Salvinia molesta were conducted originally at 18 sites in Texas and Louisiana from 1999 through 2005. However, overall project results could only ...
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Release and evaluation studies of the Brazil population of Cyrtobagous salviniae on Salvinia molesta were conducted originally at 18 sites in Texas and Louisiana from 1999 through 2005. However, overall project results could only be continually evaluated at two release and two control sites because the remainder were eventually destroyed or corrupted by floods, droughts, or herbicides. Mean fresh weight biomass of S. molesta ranged from 15.5 kg FW m(-2) during the summer to as low as 2.1 kg FW m(-2) during the winter prior to the release of C. salviniae. Insect populations established within a year of release and initially spread slowly. Damage to S. molesta increased with increasing C. salviniae detections while S. molesta biomass and surface coverage declined at both release sites by more than 99% while remaining unchanged at the control sites. Water in release sites registered higher levels of dissolved oxygen, higher temperatures, and higher pH than water in control sites. This study provides another example of the effectiveness of C. salviniae against S. molesta even in more temperate climates. Published by Elsevier B.V.
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This study was carried out to evaluate changes in the nutrient content of a tropical soil consequent upon application of leaf biomass of Cajanus cajan, Tithonia diversifolia, Acacia mangium and Grevillea robusta. Equivalent of 5 t...
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This study was carried out to evaluate changes in the nutrient content of a tropical soil consequent upon application of leaf biomass of Cajanus cajan, Tithonia diversifolia, Acacia mangium and Grevillea robusta. Equivalent of 5 t ha~(-1) of fresh leaves of each of the woody species was applied to the soil surface. Soil chemical properties were determined prior to application of leaf biomass and at 2,4, 6 and 8 weeks after. Total N, available P and exchangeable K, Ca and Mg contents of the soil increased with time and the rate of increase varied with the type of plant material applied. Eight weeks after application of the plant materials highest organic C (1.51%), K (0.77 cmol kg~(-1)) and Mg(1.55 cmol kg~(-1)) were observed in soils to which C. cajan was applied while soil contents of P and Ca were highest in soils to which T. diversifolia was applied. Values of K, Mg, P and Ca were however not significantly different between C. cajan and T. diversifolia soils. The rapid release of nutrients fromC. cajan and T. diversifolia is an indication of their suitability for soil fertility amendment in arable crop fields where an immediate release of nutrients for crop uptake is required.
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The aim of this study was to determine leaf meal production performance and leaf meal product cost of cassava, leucaena and stylosanthes forage crops, in order to prioritize the rating of the leaf meal production for supplementati...
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The aim of this study was to determine leaf meal production performance and leaf meal product cost of cassava, leucaena and stylosanthes forage crops, in order to prioritize the rating of the leaf meal production for supplementation into poultry diets. The experimental forage crops were grown on up land in the north of Vietnam with an area of 500 m2 per crop (100 mJ x 5 replicates). The experiment was conducted in three years. The fresh biomass, fresh leaves, leaf meal productivity and the productioncost of forage crops were examined. Leaf meal yield of cassava, leucaena and stylosanthes grass was respectively 9.225; 8.493 and 7.247 (tons/ha/ year). The ME yield (MJ/ha/year) was 76,434; 79,101 and 51,473, respectively. The crude protein yield (kg/ha/year) was 1,997; 2,174 and 1,243. The production cost of 1kg DM, 1 MJ ME, 1kg CP of cassava leaf meals hereinafter considered as 100%, then that of leucaena was 95.2; 92.9 and 81.8%, that of stylosanthes was 142.2; 168.9 and 182.9%. With this result,the experimental crops grown for leaf meal production for chicken diet supplement were ranked in the priority order as follows: leucaena, cassava and stylosanthes grass, respectively.
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A field experiment was conducted to evaluate the influence of row spacing and harvesting age on herb and essential oil yield of Japanese mint (Mentha arvensis L.) at Wondo Genet Agricultural Research Center, EIAR, Southern Ethiopi...
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A field experiment was conducted to evaluate the influence of row spacing and harvesting age on herb and essential oil yield of Japanese mint (Mentha arvensis L.) at Wondo Genet Agricultural Research Center, EIAR, Southern Ethiopia. The treatments were combinations of four levels of row spacing (30, 40, 50 and 60 cm) and three levels of harvesting age (60, 90 and 120 days after planting). A split plot design with three replications, row spacing as main plot and harvesting age as sub plot was used. Fresh leaf weight, leaf/stem ratio, dry leaf weight, moisture content, fresh biomass weight, essential oil content and yield were recorded. Maximum values for fresh leaf weight, leaf/stem ratio and moisture content were recorded when harvesting was made at60 days after planting. There was a statistically sharp (P < 0.01) increase in essential oil content from 0.5 to 1.4 and to 2% (w/w) with delayed harvesting from 60 to 90 and to 120 days after planting, respectively. A highly significant (P < 0.01) fresh biomass weight reduction was observed when row spacing was widened from 30 to 40 cm by 29.4% from 11,325 kg/ha. The maximum essential oil yield (39.7 kg/ha) was obtained when harvesting was made 120 days after planting at a 30-cm row spacing.
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