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1.
Even if it is less polluting than other farm sectors, grape growing management has to adopt measures to mitigate greenhouse gas (GHG) emissions and to preserve the quality of grapevine by-products. In viticulture, by land and crop management, GHG emissions can be reduced through adjusting methods of tillage, fertilizing, harvesting, irrigation, vineyard maintenance, electricity, natural gas, and transport until wine marketing, etc. Besides CO2, nitrous oxide (N2O) and methane (CH4), released from fertilizers and waste/wastewater management are produced in vineyards. As the main GHG in vineyards, N2O can have the same harmful action like large quantities of CO2. Carbon can be found in grape leaves, shoots, and even in fruit pulp, roots, canes, trunk, or soil organic matter. C sequestration in soil by using less tillage and tractor passing is one of the efficient methods to reduce GHG in vineyards, with the inconvenience that many years are needed for detectable changes. In the last decades, among other methods, cover crops have been used as one of the most efficient way to reduce GHG emissions and increase fertility in vineyards. Even if we analyze many references, there are still limited information on practical methods in reducing emissions of greenhouse gases in viticulture. The aim of the paper is to review the main GHG emissions produced in vineyards and the approached methods for their reduction, in order to maintain the quality of grapes and other by-products.  相似文献   

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Studies were conducted with two newly developed gluten‐free bread recipes. One was based on corn starch (relative amount 54), brown rice (25), soya (12.5), and buckwheat flour (8.5), while the other contained brown rice flour (50), skim milk powder (37.5), whole egg (30), potato (25), and corn starch (12.5), and soya flour (12.5). The hydrocolloids used were xanthan gum (1.25) and xanthan (0.9) plus konjac gum (1.5), respectively. Wheat bread and gluten‐free bread made from commercial flour mix were included for comparison. Baking tests showed that wheat and the bread made from the commercial flour mix yielded significantly higher loaf volumes (P < 0.01). All the gluten‐free breads were brittle after two days of storage, detectable by the occurrence of fracture, and the decrease in springiness (P < 0.01), cohesiveness (P < 0.01), and resilience (P < 0.01) derived from texture profile analysis. However, these changes were generally less pronounced for the dairy‐based gluten‐free bread, indicating a better keeping quality. Confocal laser‐scanning microscopy showed that the dairy‐based gluten‐free bread crumb contained network‐like structures resembling the gluten network in wheat bread crumb. It was concluded that the formation of a continuous protein phase is critical for an improved keeping quality of gluten‐free bread.  相似文献   

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A stratified subsurface layer of acidic soil can develop in minimally disturbed soil such as no‐till receiving injection of N fertilizer (e.g., anhydrous ammonia). The objective of this study was to evaluate the effectiveness of subsurface band treatments in alleviating soluble Al3+ and Mn2+ toxicities on sorghum growth. Soil columns 40 cm in length were packed with soil (Valentine fine sand mixed mesic Typic Ustipsamment and Thurman loamy sand mixed Mesic Udorhentic Haplustoll) with treatments applied at the 10–18 cm depth to mimic soil pH stratification. The treatments at this depth were: (1) entire layer at soil pH of 3.7; (2) band of soil 6 cm wide at pH of 5.8 with the rest of the soil at pH 3.7; (3) band of soil 6 cm wide at pH of 6.3 with the rest of the soil at pH 3.7; and (4) entire layer at soil pH of 5.8. The soil above and below the 10–18 cm depth was at pH 5.8. Sorghum (Sorghum bicolor L. Moench) was grown in the soil columns under a controlled environment for 6 weeks. High concentration of Al in soil solution was found in soil at soil pH 3.7 which was overcome by either banding to pH 5.8, 6.3, or having the soil layer at pH 5.8. Treatment with pH of 5.8 throughout the soil 10–18 cm depth produced significantly greater top growth, although all other pH or liming strategies performed better than the soil pH 3.7 treatment. The banded treatments at pH 5.8 and 6.3 allowed roots to grow below the 10–18 cm layer of soil, but root growth was still significantly less than in the soil where the entire soil treatment layer was at pH 5.8. The increase in biomass yield with soil pH of 5.8 in the entire treatment layer was higher compared to band treatment at pH 5.8; however, the lime requirement would be 3.4 times more with liming the entire layer compared to banding a portion of the soil to pH 5.8 and would thus be translated into a higher liming cost.  相似文献   

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Consumption of whole‐wheat products, including whole‐wheat spaghetti, is associated with beneficial health effects. Flavonoids and lignans are antioxidant phytochemicals that have received much attention from researchers. Investigations were conducted on the content of flavonoid glycosides, lignan diglucoside, and secoisolariciresinol diglucoside (SDG) as contributors to the health‐promoting properties of whole‐wheat spaghetti. Flavonoid glycosides present in regular and whole‐wheat spaghetti samples were identified as 6‐C‐glucosyl‐8‐C‐arabinosyl apigenin and the sinapic acid ester of apigenin‐C‐diglycoside while, in a previous study, the sinapic acid ester of apigenin‐C‐diglycoside was found only in wheat germ tissues. The content of these compounds was significantly higher in whole‐wheat spaghetti (17.0 and 15.1 μg of apigenin equivalent/g) compared to the regular brands (9.5 and 5.8 μg apigenin equivalent/g). SDG content was also significantly higher in whole‐wheat spaghetti (41.8 μg/g) compared to the regular brands (12.9 μg/g). These findings lend further support to the notion that phenolic compounds, along with dietary fiber, are concentrated in the bran layers of the wheat kernel; hence, consumption of whole grain products is strongly recommended to obtain significant levels of health‐promoting phytochemicals.  相似文献   

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The sodium hydroxide (NaOH) test for determining wheat color class depends on the observation that on soaking in NaOH, red wheat turns a darker red and white wheat turns straw yellow. To understand the mechanism of this test, Raman spectra of wheat bran, wheat starch, ferulic acid, and whole kernels of wheat, before and after NaOH soak, were studied. The major observable components in the whole kernel were that of starch, protein, and ferulic acid, perhaps esterified to arabinoxylan and sterols. When kernels are soaked in NaOH, spectral bands due to ferulic acid shift to lower energy and show a slightly reduced intensity that is consistent with deprotonation of the phenolic group and extraction of a portion of the ferulic acid into solution. Other phenolic acids, alkyl resorcinols, and flavonoids observed in the NaOH extracts of wheat by HPLC were not observed in the Raman spectra. Wheat bran accounts for most of the ferulic acid in the whole kernel, as indicated by the increased intensity of the doublet at 1,631 and 1,600 cm‐1 in the bran. The intense starch band at 480 cm‐1 in whole kernel wheat was nearly absent in the wheat bran.  相似文献   

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Data on the concentrations of natural (226Ra, 232Th and 40K) and artificial (137Cs) radionuclides and on the physicochemical properties of chernozems sampled in different years are presented. In 1952, upon the creation of the Penza-Kamensk state shelterbelt, three deep (up to 3 m) soil pits were examined within the former arable field under two-year-old plantations of ash and maple along the transect crossing the territory of the Beloprudskaya Experimental Station of the USSR Academy of Sciences in Volgograd oblast. The samples from these pits were included into the collection of dated soil samples of the Dokuchaev Central Soil Science Museum. Five pits were examined along the same transect in 2009: three pits under shelterbelts (analogues of the pits studied in 1952) and two pits on arable fields between the shelterbelts. In the past 57 years, certain changes took place in the soil structure, bulk density, and the content and composition of humus. The salt profile of soils changed significantly under the forests. The comparison of distribution patterns of natural soil radionuclides in 1952 and 2009 demonstrated their higher contents at the depth of 10–20 cm in 2009 (except for the western shelterbelt). Background concentrations of natural radionuclides in parent materials and relationships between their distributions and the salt profiles of soils have been determined; they are most clearly observed is the soils under shelterbelts. Insignificant contamination with 137Cs (up to 34 Bq/kg) has been found in the samples of 2009 from the upper (0–20 cm) horizon. The activity of 137Cs regularly decreases from the east to the west; the highest concentrations of this radionuclide are found in the topmost 10 cm. This allows us to suppose that 137Cs was brought with aerial dust by eastern winds, and the shelterbelts served as barriers to the wind flow.  相似文献   

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Understanding many soil processes, including the accumulation of organic matter and the formation and loss of soil aggregates, requires research that is conducted over decadal time periods. The dynamics of soil organic matter and soil fauna at the Horseshoe Bend (HSB) agroecosystem site in Georgia have been studied in replicated experimental plots since 1978. The experimental treatments (no-tillage (NT) and conventional-tillage (CT) regimes) are continuing to diverge in amounts and distribution of SOM in the soil profiles of HSB. Our current research focuses on two major areas: 1) long-term measurements of the gradually-increasing base of soil organic matter from C3-pathway plants, in crop rotations that have been in effect since 1997; 2) following the production, accumulation, fate and ecological effects of the Bt (Bacillus thuringiensis) proteins from the summer planting of Bt (and non-Bt) cotton in subplots within our main plots. The variation in the size of soil aggregates may influence the sequestration of Bt toxins, and their breakdown products, within soils. NT management systems at HSB generate an increasing proportion of soil macroaggregates in comparison to the markedly reduced macroaggregates in our CT plots. We suggest that NT systems may sequester more Bt-related products than will CT plots.  相似文献   

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The patterns of oribatid communities were investigated in relation to elevations (700, 1700, 2700 and 3100 m a.s.l.) and geological substrates (i.e. non-ultrabasic and ultrabasic rocks) on the slopes of Mt. Kinabalu, Sabah, Malaysia. The density and morphospecies richness of oribatid mites were greater in the non-ultrabasic plot than in the ultrabasic plot at each of the same elevations. The density and richness of Oribatid mites decreased with elevation on both substrates, but the effects of elevation on the density on non-ultrabasic were less significant than on the ultrabasic substrate. Oribatid mite density correlated positively with the concentration of soil organic phosphorus and negatively with that of exchangeable Ca in soil. The richness of morphospecies of oribatid mites positively correlated with phosphorus concentration in litter, above-ground biomass, tree diversity and litterfall amount, and negatively correlated with elevation and Ca in soil. Morphospecies from families Galumnidae, Otocepheidae, Haplozetidae and Scheloribatidae were dominant in each plot. Canonical correspondence analysis (CCA) showed the importance of elevation for the community structure of oribatid mite. In conclusion, total density or morphospecies richness of oribatid communities was influenced by both geology and elevation, and morphospecies composition was strongly influenced by elevation.  相似文献   

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We report the sequence and variability parameters of 23 microsatellite primers obtained from a commercial cultivar Gongjiao (Musa acuminata) using selectively amplified microsatellite (SAM) analysis. Polymorphisms were evaluated in a collection of 26 banana cultivars and 11 related species/subspecies. The mean number of alleles amplified per primer was 4.55 (range, 2–9), with a total of 100 alleles identified. The mean PIC value was 0.48 (range, 0.10–0.74). In addition, 22 markers also showed robust cross-species/genera amplification across 11 related species/subspecies, with the exception of ‘Xiangtuijiao’ (Ensete glaucum). Unweighted pair-grouping method with arithmetic averages (UPGMA) cluster analysis divided all the banana accessions into three main groups. The results demonstrate the usefulness of microsatellites for identification, similarity studies, and germplasm conservation in banana and related species.  相似文献   

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To evaluate the effect of climate change on ecosystem functioning, the temperature and moisture response of microbial C, N, and P transformations during decomposition of Calluna vulgaris (L.) Hull. litter was studied in a laboratory incubation experiment. The litter originated from a dry heathland in the Netherlands where P limited vegetation growth. Fresh litter was incubated at 5, 10, 15, or 20°C and at a moisture content of 50, 100, or 200% in a full factorial design. Microbial nutrient transformations and activity were evaluated during two successive periods: an initial period of 48 days characterized by microbial growth and a second period from 48 to 206 days in which microbial growth declined significantly. Temperature and moisture response of respiration rate, the metabolic quotient (qCO2), C, N, and P immobilization, net N and P mineralization and nitrification rates were evaluated by performing linear regressions. Microbial nutrient transformations and microbial activity depended both on temperature and moisture. In the first period, the respiration rate, qCO2, microbial C and N immobilization, net P mineralization, net N mineralization and net nitrification rates were more strongly affected by temperature, while the microbial P immobilization rate was more strongly affected by moisture. The respiration rate, qCO2, P immobilization rate, net P and N mineralization rate, and nitrification rate increased with temperature and moisture, while the C and N immobilization rate decreased with increasing temperature and increased with moisture. In the second period, C, N, and P immobilization and net N and P mineralization rates were significantly lower. The respiration rate and qCO2 continued to increase with temperature and moisture, but C and N immobilization rates increased with temperature and declined with increasing moisture. Net P mineralization rate decreased at higher temperature and moisture, and nitrification rate declined with increasing temperature and increased with moisture. It was concluded that plant growth in these P-limited systems is very sensitive to climate change as it strongly relies on the competition for P with microbes, and temperature and moisture have a large effect on the immobilization rate of available P.  相似文献   

16.
《Cereal Chemistry》2017,94(2):251-261
The objective for this study was to investigate the effectiveness of scaled‐up infrared (IR) heating followed by tempering steps to dry freshly harvested rough rice. An industrial‐type, pilot‐scale, IR heating system designed to dry rough rice was used in this study. The heating zone of the equipment had catalytic IR emitters that provided heat energy to the sample as it was conveyed on a vibrating belt. The sample comprised freshly harvested rough rice of long‐grain pureline (Cheniere), long‐grain hybrid (6XP 756), and medium‐grain (CL 271) cultivars at initial moisture contents of 23, 23.5, and 24% wb, respectively. Samples at a loading rate of 1.61 kg/m2 were heated with IR of radiation intensity 5.55 kW/m2 for 30, 50, 90, and 180 s followed by tempering at 60°C for 4 h, at a product‐to‐emitter‐gap size of 450 mm, in one‐ and two‐pass drying operations. Control samples were gently natural air dried in an equilibrium moisture content chamber set at relative humidity of 65% and temperature of 26°C to moisture content of 12.5% wb. The effects of IR treatments followed by tempering on percentage points of moisture removed, head rice yield, energy use, rice color, and pasting characteristics were evaluated. For all cultivars, percentage point moisture removed increased with increase in IR drying duration. For all rice cultivars, one‐pass IR treatments for 180 s resulted in head rice yield significantly lower than that of rice dried with natural air in the controlled‐environment conditions (P < 0.05). Energy required to dry rice increased with increase in drying duration. Viscosity values of all the experimental samples were significantly greater (P value < 0.05) than that of the control samples for all the cultivars, except those treated with IR for 180 s. There was a significant difference (P < 0.05) in the color index (ΔE ) of treated milled samples and the controls. In conclusion, the study provided information crucial to understanding the effects of scaled‐up radiant heating and tempering of rough rice on drying rates and rice quality for long‐grain pureline, long‐grain hybrid, and medium‐grain rice cultivars.  相似文献   

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Low soil fertility and soil acidity are among the major bottlenecks that limit agricultural productivity in the humid tropics. Soil management systems that enhance soil fertility and biological cycling of nutrients are crucial to sustain soil productivity. This study was, therefore, conducted to determine the effects of coffee‐husk biochar (0, 2.7, 5.4, and 16.2 g biochar kg?1 soil), rhizobium inoculation (with and without), and P fertilizer application (0 and 9 mg P kg?1 soil) on arbuscular mycorrhyzal fungi (AMF) root colonization, yield, P accumulation, and N2 fixation of soybean [Glycine max (L.) Merrill cv. Clark 63‐K] grown in a tropical Nitisol in Ethiopia. ANOVA showed that integrated application of biochar and P fertilizer significantly improved soil chemical properties, P accumulation, and seed yield. Compared to the seed yield of the control (without inoculation, P, and biochar), inoculation, together with 9 and 16.2 g biochar kg?1 soil gave more than two‐fold increment of seed yield and the highest total P accumulation (4.5 g plant?1). However, the highest AMF root colonization (80%) was obtained at 16.2 g biochar kg?1 soil without P and declined with application of 9 mg P kg?1 soil. The highest total N content (4.2 g plant?1) and N2 fixed (4.6 g plant?1) were obtained with inoculation, 9 mg P kg?1, and 16.2 g biochar kg?1 soil. However, the highest %N derived from the atmosphere (%Ndfa) (> 98%) did not significantly change between 5.4 and 16.2 g kg?1 soil biochar treatments at each level of inoculation and P addition. The improved soil chemical properties, seed yield, P accumulation and N2 fixation through combined use of biochar and P fertilizer suggest the importance of integrated use of biochar with P fertilizer to ensure that soybean crops are adequately supplied with P for nodulation and N2‐fixation in tropical acid soils for sustainable soybean production in the long term.  相似文献   

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