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21.
Return of high nitrogen (N) content crop residues to soil, particularly in autumn, can result in environmental pollution resulting from gaseous and leaching losses of N. The EU Landfill Directive will require significant reductions in the amounts of biodegradable materials going to landfill. A field experiment was set up to examine the potential of using biodegradable waste materials to manipulate losses of N from high N crop residues in the soil. Leafy residues of sugar beet were co‐incorporated into soil with materials of varying C:N ratios, including molasses, compactor waste, paper waste, green waste compost and cereal straw. The amendment materials were each incorporated to provide approximately 3.7 t C per hectare. The most effective material for reducing nitrous oxide (N2O) production and leaching loss of NO3? was compactor waste, which is the final product from the recycling of cardboard. Adding molasses increased N2O and NO3? leaching losses. Six months following incorporation of residues, the double rate application of compactor waste decreased soil mineral N by 36 kg N per hectare, and the molasses increased soil mineral N by 47 kg N per hectare. Compactor waste reduced spring barley grain yield by 73% in the first of years following incorporation, with smaller losses at the second harvest. At the first harvest, molasses and paper waste increased yields of spring barley by 20 and 10% compared with sugar beet residues alone, and the enhanced yield persisted to the second harvest. The amounts of soil mineral N in the spring and subsequent yields of a first cereal crop were significantly correlated to the lignin and cellulose contents of the amendment materials. Yield was reduced by 0.3–0.4 t/ha for every 100 mg/g increase in cellulose or lignin content. In a second year, cereal yield was still reduced and related to the cellulose content of the amendment materials but with one quarter of the effect. Additional fertilizer applied to this second crop did not relieve this effect. Although amendment materials were promising as tools to reduce N losses, further work is needed to reduce the negative effects on subsequent crops which was not removed by applying 60 kg/ha of fertilizer N.  相似文献   
22.
Six ruminally cannulated Wagyu (Japanese Black) steers (average initial bodyweight (BW) 387 ± 29 kg) were used in a split‐plot design experiment, comprising a 3 × 3 Latin square design (whole plot) and a randomized block design (subplot). The whole plot treatments were three different feeding levels of supplemental diet, fed at 0.2, 0.4 and 0.6% of BW, on a dry matter (DM) basis. Subplot treatments were two different supplemental diets: a potato pulp silage‐based diet (PPS) and a grain‐based diet (GRAIN). Chopped, medium‐quality cool‐season grass hay (predominately Timothy, Phleum pratense L) was fed daily at 0.7% BW (on a DM basis) as the basal diet. Each period consisted of 21 d, which included 11 d of adaptation to the diets and 10 d of the collection period. Chromium oxide was used as an indigestible marker. In situ forage degradation was measured using the nylon bag technique. The dry matter intake increased (linear; P < 0.01) as the feeding level increased and was not affected by the diet. Digestibility was not affected by any treatments. The GRAIN diet tended to decrease the rate of in situ forage degradation as the feeding level increased, but this trend was not found in the steers fed the PPS diet. Steers fed the GRAIN diet had a lower (P < 0.1) ruminal pH compared with steers fed the PPS diet. Ruminal pH was not significantly affected by feeding level; however, it was numerically higher for steers supplemented at 0.2% per BW than that for the steers supplemented above 0.4% per BW due probably to the higher starch intake. The total volatile fatty acids concentration numerically increased as the feeding level increased and was not affected by the diet. Increasing the feeding level decreased (linear, P < 0.01) the proportion of acetate. Neither diet nor the feeding level had any effects on the proportion of ruminal propionate. The results suggested that, for steers fed the PPS diet, there are not adverse effects on forage digestion in the rumen that occur as the feeding level is increased.  相似文献   
23.
落叶松KP浆碱抽提段强化漂白研究   总被引:7,自引:1,他引:6  
重点研究了落叶松KP浆CEH三段漂白碱抽提段用H2O2强化的工艺,并对添加螯合剂EDTA的效果进行了研究。  相似文献   
24.
柑桔渣经微生物发酵后烘干,以10%~15%比例取代麦麸添加到猪日粮中 饲喂育肥猪。饲料适口性良好,对猪的采食和增重均无影响。猪只经屠宰解剖表明,发酵 柑桔渣作猪饲料无任何毒副作用。具有明显的经济效益和社会效益。  相似文献   
25.
杨树纸浆林造林模式的研究   总被引:1,自引:0,他引:1  
为优化杨树小径材纸浆林模式,采用多分子的正交试验方法,通过对试验数据的统计分析和比较,筛选出较理想的纸浆林模式为:①立地条件中上等:A2B1C2———美洲黑杨·1666株/hm2·1m×6m·集约经营·6年主伐;A3B1C2———欧美杨·1666株/hm2·1m×6m·集约经营·6年主伐。②立地条件稍差:A2B2C2———美洲黑杨·1111株/hm2·1.5m×6m·集约经营·7年主伐;A3B2C2———欧美杨·1111株/hm2·1.5m×6m·集约经营·7年主伐。  相似文献   
26.
根据在鄂西大老岭林场进行的日本落叶松中龄林4种施肥量、3种N与P配比、2种施肥次数的3a试验效应研究,结果表明:不同施肥量、不同N、P比、不同施肥次数对日本落叶松中龄林生长影响不显著;但14a生B1材积生长比其它平均材积提高28.4%。施肥组合8(A1B1C1)各年生长量均高于其它组合的生长量,其材积比其它平均材积提高32.8%。  相似文献   
27.
通过实验探讨了三倍体毛白杨低硬度NaOH-AQ浆(卡伯值13.5,粘度851mL/g。白度37%,ISO)H2O2强化氧脱木质素(QOP)的工艺务件,在此基础上提出了QOP、QP全无氯漂白的漂序,此漂序可以把该纸浆漂至82.0%(ISO),粘度保持在716mL/g,漂后纸浆得率91.78%,而且该漂序可操作性强,是一种适合低硬度NaOH-AQ浆的全无氯漂白新工艺。  相似文献   
28.
研究了马尾松硫酸浆两段氧脱木质素的最佳工艺条件。结果表明,第一段氧脱木质素的条件为:氧压0.6MPa,温度100℃,时间80min,NaOH 量5%,MgSO4用量0.5%,浆浓10%;第二段氧脱木质素的条件为:氧压0.4MPa,温度90℃,时间60min,NaOH用量3%,MgSO4用量0.5%,浆浓10%。在此条件下,OIOⅡ木质素脱除率达到72.5%,粘度775.2cm^3/g,得率90.5%。经过氧脱木质素后浆的裂断长5.8km,耐破指数5.3kPa.m^2/g,撕裂指数12.7mN.m^2/g。  相似文献   
29.
全自动纸浆模塑餐具生产线气动系统设计   总被引:7,自引:0,他引:7  
介绍了全自动纸浆模塑生产线的生产工艺过程,采用信号一动作状态线图法对气动系统进行设计,并描述了纸浆模塑生产线气动系统的工作过程及系统组成。  相似文献   
30.
Two methods of cytochemical staining using Coomassie dye and Cu+-bicinchoninic acid, respectively, showed that there are proteins in thermomechanical pulp (TMP) of Norway spruce. Protein isolated from TMP was analyzed for amino acid composition. There was about twice the amount of acidic amino acid material compared with basic amino acids, and the presence of glucosamine indicated that the isolated polypeptides also contained glycoproteins. The presence of proteins in ray cells and fiber tracheids in TMP adds to the chemical heterogeneity of the structurally complex high-yield pulp.  相似文献   
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