农家有机肥抛撒装置研制与应用

为有效解决人工抛撒农家有机肥不均匀、成本高的问题,拓宽农家有机肥应用机械装备技术,研究提出了农家有机肥抛撒装置的指导思想,研制出的农家有机肥抛撒装置,主要包括支架、连接构件、传动构件和撒肥构件4部分,该装置抛撒农家肥的距离可通过调节曲面抛撒板在曲面撒板底座的位置调控,可适应于不同面积的农田;该装置可与大中型拖拉机配套使用,具有安装、拆卸简便且生产成本低等特点。每台每个工作日可均匀抛撒农家有机肥约130~150 t,其作业效率是人工抛撒的15~18倍。该装置的研制与开发为大量农家有机肥进入农田消减成本提供了技术支撑。     

生猪养殖全生产周期氮排泄参数及全国生猪粪尿氮排泄研究

为完善生猪养殖氮排泄参数体系,准确计算生猪养殖粪尿氮排泄量,本研究通过对生猪养殖全生产周期(繁殖—断奶—生长—育肥)持续开展285d的全收粪尿法代谢试验,每天记录采食量、粪尿产生量,采集样品测定水分和氮含量,系统性获取了能繁母猪空怀期、妊娠前期、妊娠中期、妊娠后期和哺乳期,以及生长肉猪保育期、生长前期、生长后期和育肥期氮的摄入与排泄参数,并结合生猪生产性能参数计算生猪氮年排泄系数。并基于中国各省生猪养殖统计数据和耕地面积,核算2000—2018年生猪养殖粪尿氮产生量变化及区域分布情况。结果表明:生猪不同生长生理阶段氮摄入量和排泄量差异显著,其中空怀期母猪为72.32 g·d~(–1)和49.42 g·d~(–1),妊娠前期为55.79 g·d~(–1)和45.36 g·d~(–1),妊娠中期为56.25 g·d~(–1)和22.27 g·d~(–1),妊娠后期为72.41 g·d~(–1)和26.36g·d~(–1),泌乳期为114.28g·d~(–1)和38.84g·d~(–1),商品猪保育期为22.86g·d~(–1)和10.96g·d~(–1),生长前期为34.87 g·d~(–1)和18.34g·d~(–1),生长后期为54.67 g·d~(–1)和34.50 g·d~(–1),肥育期为55.15g·d~(–1)和35.79 g·d~(–1)。而且各阶段尿氮排泄量都比粪氮高。商品肉猪和能繁母猪年排泄系数分别为9.00kg·头~(–1)·a~(–1)和11.75kg·头~(–1)·a~(–1)。2000—2018年,我国生猪养殖粪尿氮排泄总量呈先增后缓慢下降的趋势,而单位猪肉产品氮排泄量逐年下降,商品肉猪氮排泄量占生猪养殖粪尿氮排泄总量比重达84.03%。四川、河南、湖南、山东是我国生猪养殖氮排泄总量最大的4个省,占全国生猪养殖氮排泄总量的33.67%;而单位耕地面积生猪养殖氮承载负荷最大的省份是福建、广东、湖南、北京、上海。因此,在生猪生产中应根据群体结构和相应的氮排泄系数科学核算其氮排放量,在产业发展规划时要充分考虑环境承载力。     

Organic and mineral fertilization management improvements to a double-annual cropping system under humid Mediterranean conditions

The efficient use by crops of nitrogen from manures is an agronomic and environmental issue, mainly in double-annual forage cropping systems linked to livestock production. A six-year trial was conducted for a biennial rotation of four forage crops: oat-sorghum (first year) and ryegrass-maize (second year) in a humid Mediterranean area. Ten fertilization treatments were introduced: a control (without N); two minerals equivalent to 250 kg N ha⁻¹ year⁻¹ applied at sowing or as sidedressing; dairy cattle manure at a rate of 170, 250 and 500 kg N ha⁻¹ year⁻¹ and four treatments where the two lowest manure rates were supplemented with 80 or 160 kg mineral N ha⁻¹ year⁻¹. They were distributed according to a randomized block design with three blocks. The highest N mineral soil content was found in the summer of the third rotation, in plots where no manure was applied. The yearly incorporation of manure reduced, in successive cropping seasons, the amount of additional mineral N needed as sidedressing to achieve the highest yields. Besides, in the last two years, there was no need for mineral N application for the manure rate of 250 kg N ha⁻¹ year⁻¹. This amount always covered the oat-sorghum N uptake. In the ryegrass-maize sequence uptakes were as high as 336 kg N ha⁻¹ year⁻¹. In the medium term, the intermediate manure rate (250 kg N ha⁻¹ year⁻¹) optimizes nutrient recycling within the farming system, and it should be considered in the analysis of thresholds for N of organic origin to be applied to systems with high N demand.     

Effect of integrated nutrient management and crop diversification on productivity and nutrient balance sheet of rice-based cropping systems

A field study conducted for three crop years (June?–?July) from 1995?–?96 to 1997?–?98 at the Indian Agricultural Research Institute, New Delhi involving five rice-based cropping systems and six nutrient combinations indicated that rice?–?wheat?–?mungbean (RWM), rice?–?potato?–?mungbean (RPM), rice?–?rapeseed?–?mungbean (RRsM) and rice?–?clover (RC) cropping systems gave 0.7?–?1.0, 3.2?–?5.9, 0.2?–?2.2 and 1.5?–?3.6 t ha^?1 yr^?1, respectively, higher productivity and removed 7.9?–?22.6, 38.0?–?64.5, 53.0?–?61.8 and 51.4?–?66.1?kg ha^?1 yr^?1, respectively, more nitrogen, 2.3?–?7.1, 14.5?–?22.8, 3.8?–?7.2 and 17.3?–?21.7?kg ha^?1 yr^?1, respectively, more phosphorus and 1.6?–?11.4, 15.3?–?42.3, 8.2?–?22.7 and 40.8?–?57.8?kg ha^?1 yr^?1, respectively, more potassium than the rice?–?wheat (RW) cropping system which led to a net balance of +?151, +?58, ??153 and ??167?kg ha^?1 of nitrogen, +?13, ??27, ??8 and ??59?kg ha^?1 of phosphorus and ??549, ??551, ??558 and ??691?kg ha^?1 of potassium after three cycles of RWM, RPM, RRsM and RC cropping systems, respectively against a net balance of +?201, +?26 and ??533?kg ha^?1 of N, P and K, respectively in the RW cropping system. Application of FYM along with NPK in these cropping systems changed the negative balance of nitrogen and phosphorus into positive balance and reduced the negative balance of potassium by 151?–?378?kg ha^?1. Application of P and K fertilizers along with nitrogen also helped in arresting the negative balance of P and K under different rice based cropping systems. These results thus indicate that balanced use of NPK and FYM plays a major role for sustaining the productivity of a cropping system.     

Six-year transition from conventional to organic farming: effects on crop production and soil quality

Organic farming has become increasingly important in recent decades as the consumer has grown its focus on the food and environmental benefits of the technique. However, when compared to conventional farming systems, organic farm system are known to yield less.Presented in this paper are the results from two organic cropping systems following six years of organic management. Fertilisation management differentiated the two systems; one was fertilised with green manure and commercial organic fertilisers, while the other was fertilised with dairy manure. A conventional cropping system, managed with mineral fertiliser as typical in the southern Piemonte region (Italy), served as the bussiness as usual crop management. The first hypothesis tested related to crop yield variation during the initial phase of organic management; we expected a sharp reduction in the early phase, then minor reductions later on. The second hypothesis tested related to soil fertility variation; we expected enhanced soil fertility under organic management.Overall, the organic system produced less, relative to the conventional system in interaction with year effect. Yield reduction seemed related to the lower soil nutrient availability of organic fertilisers that provided nutrients consequent to mineralisation. Therefore, summer crops are well-suited to manure-fertilised organic farms as mineralisation happens at higher temperatures, as opposed to winter wheat, which is largely reduced in such systems. Commercial organic fertilisers can, however, limit this effect through their high nutrient availability in the winter and early springAlso shown was that soil quality, defined as a general decrease in soil organic carbon (SOC) over time in the three analysed arable systems, can be mitigated by manure additions. Green manuring can maintain SOC and increase total N in soil, only if introduced for a sufficient number of years during crop rotation. Finally, soil fertility and Potential Mineralisable N in the different systems demonstrated that organic systems managed with commercial organic nitrogen fertilisers and green manure do not improve soil quality, compared to systems managed with mineral fertilisers.     

Production, nitrogen and carbon balance of maize-based forage systems

Nitrogen (N) and carbon (C) surplus can be used as indicators of an agroecosystems’ ability to maintain soil fertility. Maize is the key crop of intensive forage systems in northern Italy, and large amounts of manure are often supplied to this crop. Different maize-based cropping systems and manure managements were compared in this paper. The following were assessed, using the results of an 11-year experiment: crop production and N uptakes; C and N surpluses; soil C and N contents. The treatments were maize for silage (Ms), maize for grain (Mg), double annual crop rotation maize–Italian ryegrass (Mr), and rotation maize–grass ley (Ml). Five fertilization management systems were adopted: 0N control, and bovine slurry and farmyard manure supplied at two levels, ranging from 215 to 385 kg ha⁻¹ of total N.

The dry-matter production of Mr was significantly higher than those of the other systems. The response of maize to fertilization was similar in all the cropping systems, except for Mr, for which the crop showed a high reactivity to N input at both fertilizer levels. Soil reserves were rapidly consumed in the unfertilized treatment of Mr, whereas the high productivity potential of this cropping system was exerted in fertilized plots. The introduction of a ley in rotation with maize reduced the system's DM production, due to the low yield potential of grass compared to that of maize, reduced the system response to fertilization, and diminished the exploitation of organic N at high fertilization rates. Cumulated N surplus caused an enrichment of the soil N pool size: 43% of excess N was retained by the soil. The relationship between the cumulated C surplus and the soil C pool size indicated that 26–27% was retained by the soil. Crop residues of the Mg system were less effective in building up the soil C pool than other C sources. Both slurry and farmyard manure exerted a positive effect on the soil C and N retention. When farmyard manure was used, 18% of C and 45% of surplus N were incorporated into the soil organic matter (SOM). Slurry also built up the SOM content, resulting in 9% of C and 24% of N surplus.     

有机肥生物菌肥对水稻产量及产量性状的影响

利用农肥、生物菌肥及磷素活化剂等生物肥料，研究了有机肥、氮肥及生物菌肥的施用量、配比以及对水稻优质米品种秋田小町产量、产量性状的影响。结果表明，有机肥、生物菌肥与氮肥配施比氮、磷、钾；氮、磷；氮、钾配合以及单独使用氮肥具有明显的增产效果，明确了各种生物肥料对产量及产量性状的影响，筛选出了农肥、生物菌肥及磷素活化剂与氮肥配施，减少氮肥用量12.5%~37.5%，不施用磷、钾肥的高产配方。     

安徽亳州畜禽规模养殖场肥水还田试验初报

[目的]探索生猪、奶牛等产生粪水(含冲刷污水,下同)较多的规模养殖场,根据粪水产生量确立粪水收集池、厌氧发酵池和储存池的池容以及配套消纳的土地面积;依据肥水营养成分、土壤本底数的检测结果,结合小麦、玉米预计单产所需要的N素量,制定“一场一策”施肥方案,推动有机肥替代化肥减量行动。[方法]规模养殖场产生的粪水进行全量收集,用泵输送到沉淀池沉淀,经固液分离,粪水输送到厌氧发酵池进行深度厌氧发酵(不少于100天),实现粪水变肥水;粪渣运送到堆肥场进行好氧堆肥。在农时季节肥水作为基肥或稀释后作为追肥还田,通过加压泵将肥水注入田间管网,还田施用。[结果]4个小麦试验田块中,肥水替代部分化肥区小麦长势正常,叶色绿色—深绿色、株高75-78㎝、病虫害为未发—轻发;平均亩穗数为41.9万穗,比全量施用化肥区多2.6万穗,提高6.61%;平均穗粒数为36.8粒,比全量施用化肥区多1.7粒,提高4.84%;4个试验点中有2个点发生少量倒伏,肥水替代区田块倒伏程度明显低于全量施用化肥区。[结论]一是测算出每1万头猪当量的养殖场,需建设厌氧发酵池和肥水储存池总容积不少于7000 m3、配套消纳土地面积不少于1300亩;肥水pH在5.5—8.5之间,指标符合要求后方可还田。二是试验发现肥水施用量替代化肥氮素用量的50%,试验田块的当年投入养分达不到农作物需肥量的要求,应根据土壤基础肥力状况,逐年增加肥水施用量,实现逐年减少化肥施用量;建议肥水替代量调整为25-30%。     

Effect of cassava mosaic disease,soil fertility,plant spacing and their interactions on cassava yields in Zanzibar

Improvement of farmers' decision-making has been recognised as critical for the implementation of IPM, yet practitioners lack sound knowledge on the 'how and why' of farmers' decision-making processes. This study explored the perceptions, pest management practice, decision tools and sources of information of smallholder farmers growing cotton in India and vegetables in Kenya. Farmers trained under an Insecticide Resistance Management and two IPM Farmer Field School projects were compared with untrained farmers from the same localities, using individual interviews and participatory group analysis methods. Trained farmers' decision-making was enhanced, by the use of more decision tools and new sources of information and technologies and they were generally more confident in their pest management strategies than untrained farmers. As a result, trained farmers reduced their pest management costs but did not always obtain higher gross margins. Issues of gender, sustainability, economics and group action are discussed, along with recommendations for research and extension to take a closer look at farmers' decision-making processes in cash and subsistence crops.     

Enhancing Soil Fertility and Wheat Productivity through Integrated Nitrogen Management

An experiment was conducted to investigate the effects of integrated nitrogen (N) management on soil fertility and crop productivity. Application of N sources in different proportions significantly (P ≤ 0.05) enhanced soil total N, organic matter, grain N uptake, straw N uptake, and grain yield. Maximum grain yield, total soil N (%), and organic matter (%) were recorded from the treatment of poultry manure as compared with other sole N sources. Among integrated application of N sources, 25% poultry manure + 75% mineral N source produced the greatest grain yield. Maximum total soil N and organic matter were observed in the combined application of 75% poultry manure + 25% mineral N. Maximum grain N and straw N uptake was recorded from the treatment applied with farmyard manure as sole N source. However, among integrated application of N sources, 25% poultry manure + 75% mineral N source resulted in the greatest grain N and straw N uptake.