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101.
我国农村沼气发展影响因素分析 总被引:4,自引:0,他引:4
分析了纬度和人均收入对我国农村沼气应用分布的影响,认为气温是农村沼气推广和利用的一个决定性因素,而在纬度对农村沼气建设无较大妨碍时,经济水平(农民人均收入的高低、商业化程度)对沼气推广应用存在负相关关系。 相似文献
102.
沼液配施对水培油菜产量及品质的影响 总被引:5,自引:0,他引:5
通过以沼液、油菜为试验材料,在完全随机区组设计的条件下,利用水培法,研究了不同浓度沼液对油菜产量及品质的影响,结果表明:施用沼液的处理比空白油菜产量平均提高22.64%,处理间达显著水平。其中Vc提高了42.6%,还原糖提高了60.1%,同时沼液处理均能降低油菜中硝酸盐和总酸的含量,分别降低了16.9%,33.6%。 相似文献
103.
沼渣在棉花上的施用效果初探 总被引:5,自引:0,他引:5
通过田间试验,初步探讨了沼渣在山西省临猗县棉花上的肥效。结果表明:棉花基施沼渣、猪粪能够改善棉花的生物学性状,主要表现为叶片增厚增大、光合作用增强、脱铃率降低、铃重和衣分增加,为提高产量打下了基础。基施沼渣3.0万kg/hm2,比对照增产27.4%~27.9%;基施沼渣1.5万kg/hm2,比对照增产6.8%~10.4%。 相似文献
104.
沼肥不同用量对小麦光合特性和产量的影响 总被引:6,自引:0,他引:6
在大田条件下用沼肥作基肥,通过6个不同施用量观测其对小麦不同时期叶片光合特性和产量的影响,结果表明:施用沼肥,能有效地提高小麦叶片的叶绿素含量(Chl)、光合速率(Pn)、叶片水分利用效率(WUE)和产量;在22500 kg/hm2施肥水平下,小区产量、单位面积穗数、千粒重最高;在30000 kg/hm2施肥水平下的光合速率、蒸腾速率、拔节期叶绿素含量最高。在37500 kg/hm2施肥水平下的株高、穗下节长、穗粒数明显高于对照;基肥施用沼肥的各处理小麦产量比对照提高了12.4%~26.14%,沼肥施用量在0~30000 kg/hm2范围内叶绿素含量、叶片光合速率、产量随着施肥量的增加而提高,但过量的施用沼肥会抑制叶绿素的合成、降低光合速率。沼肥在麦田作基肥的最佳施肥量应在22500~30000 kg/hm2左右。 相似文献
105.
The trend towards specialization in conventional farming led to large agricultural areas in Germany and in Europe lacking livestock. Also stockless organic farming has increased during recent years. In organic farming clover/grass-ley (CG) provides nitrogen (N) to the whole cropping system via symbiotic N2 fixation and also controls certain weeds. A common practice in organic farming, when ruminants are not present, is to leave the biomass from CG in the field for their residual fertility effect. CG biomass, crop residues (CR) and cover crops (CC) represent a large unexploited energy potential. It could be used by anaerobic digestion to produce biogas. A field experiment was carried out by implementing a whole cropping system with a typical crop rotation for such farming systems on the research station Gladbacherhof from 2002 to 2005. The crop rotation consisted of six crops (two legumes and four non-legume crops). The aim was to evaluate whether the use of N could be improved by processing biomass from CG, CR and CC in a biogas digester and using the effluents as a fertilizer, compared to common practice. In the control treatment, represented by the usual stockless system, the CG, CR and CC biomass were left on the ground for green manure purposes. In the biogas systems these substrates were harvested for digestion in a biogas plant. The effluents of digestion were used to manure the non-legumes in the same crop rotation. Results indicate that digestion of CG, CR and CC can increase the crop dry matter and N yields and the N content of wheat grains in organic stockless systems. Harvesting and digestion of residues and their reallocation after digestion resulted in a better and more even allocation of N within the whole crop rotation, in a higher N input via N2 fixation and lower N losses due to emissions and probably in a higher N availability of digested manures in comparison to the same amounts of undigested biomass. 相似文献
106.
Maize (Zea mays L.) is the most important substrate for biogas production in Germany. This study was conducted to determine the influence of harvest date and hybrid maturity on the yield and quality of maize biomass for anaerobic methane production. In 2004 and 2005, maize hybrids of widely contrasting maturity were grown on a loamy sand soil (Haplic Luvisol) near Braunschweig, Germany. Whole-plant yield was determined several times after female flowering and the biomass analysed for nutrient composition. The specific methane yield (SMY) was measured using 20 l batch digesters. In both experimental years, the late energy maize prototypes had a lower concentration of fat and protein, but higher concentration of ash, detergent fibre, and lignin as compared with the climatically adapted medium-early hybrids. Despite substantially different nutrient concentration among the maize hybrids, no clear-cut association existed between chemical composition and specific methane yield. Contrary to the medium-early hybrids, the late hybrids attained both maximum specific methane yield and maximum methane hectare yields at the final harvest date. In the very long growing season of 2004, the highest individual methane yield of 9370 N m3 ha−1 was obtained by the hybrid with the latest maturity used in the study. It appears that late energy maize, which can take full advantage of the growing season, is better suited for biogas production, provided that the whole-plant dry matter concentration is high enough to produce good quality silage. 相似文献
107.
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109.
对泥浆漏失的原因,进行具体分析,并提出了泥浆漏失处理方案;对岩层的漏失地段,采用不同泥浆性能,使钻探工艺更加合理。 相似文献
110.
Anaerobic digestion of organic materials generates residues of differing chemical composition compared to undigested animal manures, which may affect the soil microbial ecosystem differently when used as fertilizers. This study investigated the effects of two biogas residues (BR-A and BR-B) and cattle slurry (CS) applied at rates corresponding to 70 kg NH4+-N ha−1 on bacterial community structure and microbial activity in three soils of different texture (a sandy, a clay and an organic clay soil). 16S rRNA genes were targeted in PCR reactions and bacterial community profiles visualized using terminal restriction fragment length polymorphism. General microbial activity was measured as basal respiration (B-resp), substrate-induced respiration (SIR), specific growth rate (μSIR), metabolic quotient (qCO2) and nitrogen mineralization capacity (NMC). Non-metric multidimensional scaling analysis visualized shifts in bacterial community structure related to microbial functions. There were significant differences in bacterial community structure after 120 days of incubation (+20 °C at 70% of WHC) between non-amended (control) and amended soils, especially in the sandy soil, where CS caused a more pronounced shift than biogas residues. Terminal-restriction fragment (TRF) 307, the predominant peak in CS-amended sandy soil, was identified as possibly Bacillus or Streptococcus. TRF 226, the dominant peak in organic soil amended with BR-B, was classified as Rhodopseudomonas. B-resp significantly increased and SIR decreased in all amendments to organic soil compared with the control, potentially indicating decreased efficiency of heterotrophic microorganisms to convert organic carbon into microbial biomass. This was also reflected in an elevated qCO2 in the organic soil. The μSIR level was higher in the sandy soil amended with BR-A than with BR-B or CS, indicating a shift toward species capable of rapidly utilizing glucose. NMC was significantly elevated in the clay and organic soils amended with BR-A and BR-B and in the sandy soil amended with BR-B and CS. Thus, biogas residues and cattle slurry had different effects on the bacterial community structure and microbial activity in the three soils. However, the effects of biogas residues on microbial activities were comparable in magnitude to those of cattle slurry and the bacterial community structure was less affected. Therefore, we do not see any reason not to recommend using biogas residues as fertilizers based on the results presented. 相似文献