2FL-2农家肥和化肥联合施用机的研制

对农家肥和化肥混合施用的机械化状况进行调查后，利用施肥技术，对垄上农家肥和化肥施肥机械进行研究，研制出了垄上农家肥和化肥联合施肥机械，用于底肥和追肥施用，并进行了田间试验，结果表明，该机具设计合理，具有结构紧凑、调整方便等特点。通过性能测验得出农家肥施肥深度为100-150 mm、化肥施肥深度50-70 mm、农家肥施肥量0.5-0.7 kg·m-2、化肥施肥量0.015-0.03 kg·m-2、作业速度1.94 m·s-1。该机施用于农家肥和化肥垄作施肥，主要用于起垄机和播种机的配套施肥装置，其使用有利于提高液态肥料的利用率、保护环境、减少环境污染。

Characters of Bio-organic Fertilizer and Trails on Its Effect When Applied to Peach

[Objective] This study aimed to investigate the characteristics of bio-organic fertilizer and its effect when applied to peach.[Method] Through launching demonstration trial on the application of bio-organic fertilizer in the major fruit producing areas in Liaoning Province,the effects of bio-organic fertilizer on peach growth and soil were investigated.[Results] After application of bio-organic fertilizer,both the peach yield and fruit quality were improved to some extent,of which yields was increased by 16.4％ compared with the control,and vitamin C and total sugar contents were also significantly increased; application of bio-organic fertilizer also improved the contents of total nitrogen,rapidly available phosphorus,available potassium and organic matter in soil,and reduced the soil volume weight.[Conclusion] Bioorganic fertilizer can significantly improve fruit yield and quality,as well as improving orchard soil and protecting the environment,thus possessing a bright application prospect in the production of green fruits.

Effects of Nitrogen Treatments on Organic Carbon Mineralization of Citrus Orchard Soil

[Objective] This study aimed to investigate the effect of soil organic carbon mineralization at different temperature on the amount of nitrogen application, in order to provide references for the establishment of carbon circulation model for orchard eco-system. [Method] The effects of nitrogen treatments on soil organic carbon mineralization of citrus orchard soil were investigated under 10, 20, 30 ℃ by laboratory simulated experiment. [Result] The mineralization rate decreased quickly at the be- ginning of the experiment but remained stable at the late period under three temper- ature treatments. The amounts of CO2 ranged from 1 328.25-2 219.42 mg/kg under three temperature condition, and the amount of soil organic carbon mineralization of 100 mg/kg （N4） treatment was the greatest, while that of CK was the lowest. High level nitrogen treatment （N4 and N3） were significant higher than the lower level nitro- gen treatment （N2 and N1）. The soil organic carbon mineralization rate increased with the temperature from 10 to 30℃. The dependence of soil carbon mineralization to temperature （Q10） was different under different nitrogen treatments that the Qlo value of N2 treatment was the lowest while that of the N4 treatment was the greatest. The soil organic carbon mineralization in Citrus orange orchard soil was affected significantly by high level nitrogen treatment, but with no significance under lower nitrogen treatment. [Conclusion] The dependence of soil carbon mineralization to temperature （Q10） increased with the increasing nitrogen input. The combination of nitrogen with temperature may increase the CO2 emission from Citrus orchard soil.

Effect of Organic Manure Application on Physical Properties and Humus Characteristics of Paddy Soil

Long-term field experiment was established in 1978 on a coastal paddy soil to determine the effect of applicationof pig manure, rice straw and chemical N fertilizer on the physical property and humus characteristics of soil . Resultsshowed that the porosity, the microstructural coefficient, the reactivities of organic C and N, the ΔlogK value, thedegree of oxidation stability, the contents of O-alkyl C and alkyl C, and the ratio of aliphatic C to aromatic C ofhumic acid from soils received organic manure increased, whereas, the ratio of < 10 μm to >10 μm ofmicroaggregates, the humification degree of humus, the degree of organo-mineral complexation, the number-averagemolecular weight, the C/ H ratio. the contents of carboxyl and aromatic C of HAs in them decreased. These resultsindicated that the application of organic manure not only improved the physical property of the paddy soil but alsomade the HA more aliphatic in structure and younger in origin.

A practical soil management to improve soil quality by applying mineral organic fertilizer

Heavy use of chemical fertilizer causes increasing soil and environmental crisis, and the use of organic fertilizer increases obvious in recent years. In this study,mineral organic fertilizer(MOF) and compound fertilizer(CF) were applied in amaranth culture to explore the effects of these two kinds of fertilizers on soil quality and the potential function for CO_2 fixation. Some soil parameters were tested, e.g. p H value, organic carbon content, microbial biomass, urease activity, and available potassium content. In addition, some parameters of soil infiltration water were also determined, such as p H and HCO_3^- concentration. Experimental results showed that MOF improved soil quality and amaranth biomass and increased possible soil carbon sink.On the contrary, the utilization of CF worsened soil quality and made the soil acidize. These results suggested that MOF can partially replace CF to improve plant growth, soil quality and possible CO_2 sink.

Enzyme Activity in Water-Stable Soil Aggregates as Affected by Long-Term Application of Organic Manure and Chemical Fertiliser

The activities of invertase, protease, urease, acid phosphomonoesterase, dehydrogenase, and catalase in different fractions of waterstable aggregates (WSA) were examined in long-term (26 years) fertilised soils. The long-term application of organic manure (OM) with chemical fertiliser (CF) significantly increased macroaggregate and decreased microaggregate percentages, enhanced the mean weight diameter, and significantly increased soil total carbon (TC) and total nitrogen (TN) contents of WSA in different size fractions. Combined fertilisation with OM and CF also increased invertase, protease, urease, acid phosphomonoesterase, dehydrogenase, and catalase activities of WSA in different size fractions. Enzyme activities were higher in macroaggregates than in microaggregates. The distribution of enzyme activities generally followed the distribution of TC and TN in WSA. The geometric mean of the enzyme activities in different WSA of OM-treated soils was significantly higher than that in soils treated with 100% CF or no fertiliser. The results indicated that the long-term combined application of OM with CF increased the aggregate stability and enzyme activity of different WSA sizes, and consequently, improved soil physical structure and increased soil microbial activity.

Influence of Different Plant Materials in Combination with Chicken Manure on Soil Carbon and Nitrogen Contents and Vegetable Yield

The use of plant materials as soil amendments is an uncommon practice amongst major farming communities in Ghana, although it is necessary for soil fertility improvement. An examination of the effects of soil amendments is necessary to encourage the use of under-utilized organic resources in Ghana. Thus, a field experiment was conducted using 8 different tropical plant materials mixed with chicken manure as soil amendments for growth of tomato as a test crop. The plant materials included Leucaena leueocephala, Centrosema pubescens, Sesbania sesban, Gliricidia sepium, Mucuna pruriens, Pueraria phaseoloides, Azadirachta indiea, and Theo- broma cacao. There were two other treatments： one with equivalent amounts of chemical fertilizers and the other with no-fertilizer input （control）. Plant materials were mixed with chicken manure to obtain a uniform carbon-to-nitrogen （C：N） ratio of 5：1. Except the no-fertilizer control, all treatments received the same amount of nitrogen （N）. To clarify the decomposition pattern of the plant materials in soil, an incubation experiment was conducted using only the plant materials before the field experiment. The Glirieidia treatment released significantly more mineral N than the other plant materials in the incubation experiment. However, the tomato fruit yield was not enhanced in the Gliricidia treatment in the field experiment. The known quality parameters of the tested plant materials, such as total N, total carbon （C）, C：N ratio, and total polyphenols, had minimal effects on their mineralization dynamics. Azadirachta showed the best synergistic effect with chicken manure through significantly increasing soil microbial biomass and fruit yield of tomato. This result provides insights into the possible adoption of Azadirachta in combination with chicken manure as a soil amendment in small-scale agricultural holdings.

Dynamic Relationship Between Biologically Active Soil Organic Carbon and Aggregate Stability in Long-Term Organically Fertilized Soils

Biologically active soil organic carbon （BASOC） is an important fraction of soil organic carbon （SOC）, but our understanding of the correlation between BASOC and soil aggregate stability is limited. At an ecological experimental station （28° 04＇-28° 37＇ N, 116° 41＇-117° 09＇ E） in Yujiang County, Jiangxi Province, China, we analyzed the dynamic relationship between soil aggregate stability and BASOC content over time in the red soil （Udic Ferrosols） fertilized with a nitrogen-phosphorus-potassium chemical fertilizer （NPK） without manure or with NPK plus livestock manure or green manure. The dynamics of BASOC was evaluated using CO2 efflux, and soil aggregates were separated according to size using a wet-sieving technique. The soils fertilized with NPK plus livestock manure had a significantly higher content of BASOC and an improved aggregate stability compared to the soils fertilized with NPK plus green manure or NPK alone. The BASOC contents in all fertilized soils decreased over time. The contents of large aggregates （800-2 000 μm） dramatically decreased over the first 7 d of incubation, but the contents of small aggregates （〈 800 μm） either remained the same or increased, depending on the incubation time and specific aggregate sizes. The aggregate stability did not differ significantly at the beginning and end of incubation, but the lowest stability in all fertilized soils occurred in the middle of the incubation, which implied that the soils had a strong resilience for aggregate stability. The change in BASOC content was only correlated with aggregate stability during the first 27 d of incubation.

Ultrahigh performance concrete–properties, applications and perspectives

Over the last twenty years,remarkable advances have taken place in the research and application of ultra-high performance concrete(UHPC),which exhibits outstanding mechanical properties and excellent durability.It has shown great potential for the next generation infrastructure construction from the sustainability point of view.This paper will give an overview on UHPC,with particular focus on the properties,applications and perspectives.After several decades of development,several types of commercial UHPC materials are available in the market,and the properties of UHPC have been characterized by numerous experimental and field tests.Generally speaking,the performance(e.g.mechanical properties and durability)of UHPC is much better than normal concrete(NC)and high performance concrete(HPC).Therefore,the uses of UHPC are growing all over the world,in both fields of new construction and retrofitting.Nevertheless,it is still a special material and technology,which is not worldwide accepted.So some application prospects of UHPC are briefly introduced in the paper,and the efforts,which have to be made to turn UHPC into a widespread‘regular’technology,are discussed.This paper aims to help designers,engineers,architects and infrastructure owners to know the capacities of UHPC and thus to increase the applications of this material.