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121.
修复植物香薷堆肥对缺铜土壤上冬小麦生长和铜吸收的初步研究 总被引:2,自引:1,他引:1
通过堆积腐解处理生长在Cu污染土壤上的修复植物-海州香薷,将其研制成堆肥,作为基肥施用于缺Cu土壤,以矫正作物缺Cu症状。盆栽试验研究了这种堆肥对冬小麦(TriticumaestivumL.)生长和Cu吸收的影响。结果表明,施用海州香薷堆肥可显著提高生长在缺Cu土壤上的小麦的株高、生物量和籽实千粒重。与CK相比,千粒重可提高58.9%,籽实产量提高近1倍;而在这种缺Cu土壤上单纯施加N、P、K化肥,反而降低小麦生物量和籽实千粒重。可见,将Cu污染土壤上生长的修复植物海州香薷制成堆肥,施用于缺Cu土壤是一种可实现修复植物资源化的有效途径。 相似文献
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124.
研究了7种不同碳氮比栽培料对猴头菌菌丝和子实体生长发育及品质的影响,旨在筛选出最适宜猴头菌生长发育的碳氮比。结果表明:猴头菌菌丝在7种碳氮比栽培料处理上均能生长,且都能形成子实体,但存在差异。在碳氮比为28:1~38:1的栽培料处理上菌丝生长最好,表现为菌丝生长速度快,且洁白浓密,处理间无显著性差异,但与其他处理间存在显著差异。在所设置的处理间,随碳氮比的增加,生物学效率呈增加趋势,当碳氮比达到38:1时生物学效率达最高峰,此后,随碳氮比的增加生物学效率逐渐下降。综合考虑营养生长和生殖生长两方面的因素,最适宜猴头菌生长发育的碳氮比为38:1。 相似文献
125.
施用秸秆堆腐肥对黑土农田养分及玉米产量的影响研究 总被引:12,自引:4,他引:12
试验研究表明应用秸秆腐解剂可快速堆腐秸秆 ,黑土农田施用充分腐熟的秸秆肥配施NPK化肥 ,耕层土壤平均年提高有机质 0 .4g/kg ,全N 0 .18g/kg ,速效氮 9.93mg/kg ,速效磷 1.8mg/kg ,速效钾 4mg/kg ,土壤容重年降低0 .0 2g/cm3 ,玉米增产 15 .7%。 相似文献
126.
Barren desert soil that otherwise could not support perennial plant growth was amended with six levels of common agricultural compost. Seedlings of the giant cardon cactus, one of the primary plant species responsible for soil stabilization in the southern Sonoran Desert, were inoculated with the plant-growth-promoting bacterium Azospirillum brasilense Cd, planted, and grown for 18 months under nursery conditions typical for slow-growth cacti. Control plants were grown without compost amendment, without inoculation (negative control), or in fertile, rare “resource island” soil preferred by cardon seedlings (positive control). During the prolonged growth period, the decisive factor in seedling growth in barren soil was the addition of small amounts of common compost; 6 to 25% of the growth substrate volume gave the best growth response and, to a lesser extent, so did inoculation with A. brasilense Cd. Although the bacteria significantly affects plant growth when amended with “resource island” soil and added to barren soil, its effect on plant growth was far smaller than when compost alone was added. Compost added to barren soil significantly increased the dry weight parameters of the plant to almost similar levels obtained by the “resource island” soil; however, the compost amendment supports a more voluminous and greener plant with elevated pigment levels. This study shows that barren soil supplemented with compost can replace the rare “resource island” soil for cardon nurseries destined to abate soil erosion in the desert. 相似文献
127.
A screening assay for isolating humic-substances degrading fungi from biosolids compost at the thermophillic phase employed using plates containing 2,2′-azino-bis(3-ethylbenzothiazoline-sulfonic acid) (ABTS), MnCl2 or the monoazo dye Acid Red 183. Two of the most active fungi out of 70 fungal strains isolated were identified based on rDNA sequences and designated Trametes sp. M23 and Phanerochaete sp. Y6 (accessions no. DQ408582 and DQ438910). These isolates, when compared to a model white-rot fungi T. versicolor and P. chrysosporium, showed the ability to bleach humic acids extracted from biosolids compost while growing under solid-state conditions using perlite as a solid support. T. versicolor and Trametes sp. M23 also exhibited the ability to bleach humic acids from a peat source. Interestingly, only Trametes sp. M23 bleached leonardite humic acid, which is considered to be a highly aromatic and stable type of natural organic matter. To the best of our knowledge, this is the first report of white-rot fungi being isolated and identified from thermophilic composts. Since these fungi are capable of degrading lignin and humic acid and were found active in organic-matter-degradation processes, we suggest that they may play a significant role in the degradation and transformation of these refractory substances during composting. 相似文献
128.
Composting is a partially controlled bio-oxidative process through which highly heterogeneous organic matter (OM) in its solid-state transforms into a humified material. The variability of the OM undergoing composting makes compost research a great challenge. Our purpose was to define chemical and plant response characteristics of a variety of composts, grouped based on their major source materials. Thirty-seven commercial composts were collected from France, Greece and the Netherlands. When grouped by country of origin, significant differences were found in %OM, %C, %N, dissolved organic carbon (DOC) concentration, electrical conductivity (EC) and NO3 concentration. These differences may be attributable to source materials or local regulations and quality control measures. When the composts were classified into 7 groups by their source materials: wood, green, manure, grape marc (GM), oilcake, spent mushroom substrate and municipal solid waste-based composts, significant differences between groups were found in %OM, %C, %N, DOC, pH, EC, NO3 and soluble sugars. Extracts of composts from all groups, except GM and oilcake had absorbance in the UV and visible range that was linearly correlated with DOC. GM and oilcake compost extracts had lower absorbances and distinctly lower specific UV absorbance (SUVA). Diffuse reflectance infrared Fourier Transform (DRIFT) spectra of the composts from different source groups also exhibited distinct group features (e.g. the ratio of polysaccharide to aliphatic peak intensity), whereas NMR spectra did not. Cucumber plants grown on manure-based composts had greater fresh weight than those grown on other composts. Plants grown on oilcake and GM composts exhibited low fresh weight. The difference in characteristics of the oilcake and GM composts may be a result of their unique chemical composition which slows their degradation. It may also be related to their relatively low degree of maturity, which is a consequence of their slow degradation. 相似文献
129.
Evaluation of maturity of poultry manure compost by phospholipid fatty acids analysis 总被引:1,自引:0,他引:1
Kotaro Kato Nobuaki Miura Hiroyasu Tabuchi Ichio Nioh 《Biology and Fertility of Soils》2005,41(6):399-410
To study the influence of the physical properties of compost feedstock on some characteristics associated with maturity, two types of compost were made from poultry manure, rice husk, and rice bran. The bulk density of one type (PMC) was always higher than that of another type (NMC) during composting. In the case of PMC, the change in temperature, decrease in NH4+, appearance of NO3–, and increase in germination indices (GI) with Japanese Komatsuna (Brassica campestris cv. Osome) were all more delayed than in NMC. As the composting process progressed, the proportion of branched (iso-, anteiso-, 10Me-) and saturated phospholipid fatty acids (PLFA) [BRANCHED FAMES (fatty acid methyl esters), biomarkers for gram-positive bacteria] gradually increased, then reached plateau. The high proportion of BRANCHED FAMES was maintained over a long storage period. The straight hydroxyl and saturated PLFAs (SOH-FAMES) initially increased, then disappeared with the progress of composting. The increase in BRANCHED FAMES and the decrease in SOH-FAMES were more delayed in PMC than NMC. The day on which the proportion of BRANCHED FAMES reached plateau and the proportion of SOH-FAMES dipped below 2 mol% coincided with the maturity stage based on the changes of physicochemical characteristics and GI. The composition of BRANCHED FAMES showed highly positive and negative correlation with GI and NH4+, respectively. In the case of SOH-FAMES, inverse correlations were observed. This indicates that the proportion of BRANCHED FAMES and/or SOH-FAMES can be used as a tool for evaluating the maturity of poultry manure compost. 相似文献
130.
Phenanthrene sorption by compost humic acids 总被引:4,自引:0,他引:4
Nonlinear isotherms were observed for sorption of polycyclic aromatic hydrocarbons (PAHs) to humic materials, but the exact sorption mechanism is not clearly understood. This study aimed to investigate the sorption of PAHs by compost humic materials. Humic acids (HAs) were progressively extracted from two compost samples by a 0.1-M sodium pyrophosphate solution. Sorption of phenanthrene by the extracted HAs was studied with a batch equilibration technique. Competitive sorption between pyrene and phenanthrene in the HAs was also examined. Elemental analysis and solid-state 13C NMR were used to characterize HAs. All sorption isotherms were nonlinear although these samples contained little black carbons if any. Isotherm linearity increased with increasing number of extractions. Isotherm nonlinearity was negatively related to HA aliphaticity. Addition of pyrene to the phenanthrene-HA system increased isotherm linearity. Competition between phenanthrene and pyrene sorption was more pronounced in the first fraction of HAs with a higher content of aromatic moieties. This study showed that humic materials alone could lead to nonideal sorption for PAHs. 相似文献