南京市农业循环经济发展评价指标体系构建与对策

基于农业循环经济的内涵、目标以及评价指标体系构建的原则,构建了区域农业循环经济发展评价指标体系,包括经济和社会发展、资源减量投入、资源循环利用和资源环境安全4方面共18项指标.利用相应的数据对南京市1990年、1995年、2000年和2005年的农业循环经济发展指数进行了分项评价和综合评价.结果表明:近年来南京市农业循环经济发展的综合指数呈逐步提高的趋势,说明近年来南京市农业循环经济的发展总体呈优化趋势;而各分项评价指数则表现为波动的变化态势,说明南京市农业循环经济的发展在某些方面还不稳定,甚至有局部恶化的情况.评价的结果也指出,南京市农业循环经济的发展还需要坚定不移地加快农村经济发展,严格控制化肥、农药和农膜等产品的使用强度,并不断创新农业循环经济发展途径等.     

城市污泥与稻草堆肥的腐熟度指标研究

采用翻堆方式将稻草与未消化城市污泥进行堆肥,测定常见几种化学和生物参数的变化,探讨其作为腐熟度指标的可行性。结果表明,(C/N)终点/(C/N)起始比值和铵态氮可作为堆肥腐熟度的指标,当(C/N)终点/(C/N)起始小于0.6和铵态氮浓度低于400mg·kg-1时,堆肥基本腐熟。水溶性有机碳与水溶性铵态氮之比值也可作为堆肥腐熟度的新的复合指标,当比值大于9时,堆肥基本腐熟。挥发性固体重、C/N、pH及NO3--N与堆肥原料有关,只可作为参考。     

纸浆厂废弃物和堆肥对番茄早期生长的影响

本文比较了来自不同有机物组合的三种堆肥（马粪和垫草,貂场废弃物,城市生活垃圾和污泥）和纸浆厂固体废弃物对提高番茄生长的影响.番茄、水芹、小红萝卜种植在有机养分贫瘠的土盆中,发芽后评价四个处理的植物毒性.结果表明：马粪和垫草,貂场废弃物能刺激番茄苗根部和地上部的生长,城市生活垃圾堆肥和纸浆厂固体废弃物有强烈的抑制作用;城市生活垃圾堆肥和无修复的土壤同样抑制种子萌发,纸浆厂固体废弃物处理使水芹和小红萝卜苗畸形发育,这些处理的有毒成分和养分失调都可能造成生长抑制的影响,不经过腐熟的纸浆厂固体废弃物施用到农业土壤有可能对蔬菜类植物造成有害的影响.     

鸡粪菌渣好氧堆肥过程中氨氧化古菌及氨氧化细菌群落的动态变化

以amo A基因为标记,通过Real-Time PCR和限制性片段长度多态性(Restriction fragment length polymorphism,RFLP)法对鸡粪菌渣好氧堆肥过程中的氨氧化古菌(Ammonia-oxidizing archaea,AOA)和氨氧化细菌(Ammonia-oxidizing bacteria,AOB)进行了丰度及群落结构的分析。结果表明,在堆制初期、好氧发酵高温期及后熟期,AOB的amo A基因丰度均占主导优势,是AOA的38~992倍。进入好氧发酵高温期,AOA amo A基因丰度下降至发酵前的0.9%,AOB下降至17.6%,后熟期AOA与AOB的amo A基因丰度与好氧发酵高温期相当。在上述3个阶段AOA与AOB各自存在一个绝对优势菌群,分别为Cluster 3和Nitrosomonas europaea,其中Cluster 3克隆子数目分别占整个克隆文库的70.73%、54.28%、72.45%,Nitrosomonas europaea克隆子数目分别占整个克隆文库的78.44%、93.20%、94.27%。堆肥3个阶段AOA的多样性指数变化不大,Shannon-Wiener值维持在1.53~1.60,但群落结构发生明显演替,随着堆肥温度升高,堆肥前期的一些菌群(Cluster 4、Cluster 5、Cluster 6)逐渐消失,新的菌群Cluster 1出现并成为堆肥中后期的第二大优势菌群。AOB无论是多样性指数还是群落组成,都发生剧烈的变化。AOB在堆肥前期Shannon-Wiener指数值最大(1.47),种群数最多(6个基因簇,分别为Nitrosomonas europaea Cluster,Nitrosomonas halophila Cluster,Nitrosomonas communis Cluster,Nitrosomonas nitrosa Cluster,Nitrosospira briensis Cluster,Nitrosospira multiformis Cluster);进入高温发酵期,Shannon-Wiener下降至0.45,群落结构单一,只有Nitrosomonas europaea Cluster和Nitrosomonas halophila Cluster;进入后熟期,AOB多样性及种群数得到一定程度的回升。     

Estimated nitrogen use efficiency,surplus, and partitioning in young apple trees grown in varied organic production systems

A certified organic apple (Malus × domestica Borkh.) orchard was established to study the interaction of ground cover management systems (GMS) and nutrient sources (NS) on nitrogen (N) use efficiency and N surplus in the Southern U.S. for three years. Trees treated with green compost (GC) and wood chips (WC), regardless of the NS, had greater N accumulation and leaf N use efficiency compared to the shredded paper or mow-and-blow treated trees. The WC-treated trees had comparably low N surplus relative to the GC trees that induced more [NO₃⁻] in soil or soil solution in the rooting zone in September in year 3. GC trees had the highest [NO₃⁻] mineralization in the soil during winter. GMS had greater overall effects on the tree response variables than did the NS.     

Water and nutrient use efficiency of a low-cost hydroponic greenhouse for a cucumber crop: An Australian case study

The Australian greenhouse industry is primarily dominated by low-cost hydroponic greenhouses for delivery of water and nutrients to plants to grow a variety of vegetable crops including cucumber and tomato. The nutrient rich drainage water from these greenhouses is generally released into the local environment causing pollution concerns. This study was initiated to investigate the opportunities in recycling drainage water to increase water and nutrient-use efficiency of hydroponic greenhouses and reduce the environmental impact of the drainage water discharge. Results indicated that a total of 4.15 ML/ha of irrigation water was applied during the 13 weeks crop growing period of which 2.56 ML/ha was drained off and 1.59 ML/ha was used to meet the crop evapotranspiration demand. The study showed that the recycling of the drainage water resulted in a 33% reduction in potable water used for irrigation in cucumber production. The drainage water contained 59% applied N, 25% applied P and 55% applied K and illustrated the potential for nutrient recovery and production cost savings through the reuse of drainage water. This case study demonstrates that some relatively simple changes in irrigation practices within greenhouse systems to recycle drainage water can considerably improve sustainability of low-cost hydroponic greenhouses and help minimise the environmental footprint of the greenhouse industry.     

Characterization and partial purification of a bacteriocin‐like substance produced by thermophilic Bacillus licheniformis H1 isolated from cow manure compost

The production and partial characterization of bacteriocin‐like substances (BLSs) produced by bacteria isolated from cow manure compost were investigated. Eight BLS producers, which exhibited inhibitory activity against pathogenic bacteria, were isolated from cow manure compost at different stages of the composting process. The pile temperature ranged from 9.1°C to 73.2°C. The BLSs showed thermostability, but the BLS producers were not thermostable except for the H1 producer. Thermophilic Bacillus licheniformis H1 was further characterized. The culture supernatant of B. licheniformis H1 exhibited antagonistic activity against various species of Gram‐positive bacteria such as Listeria monocytogenes ATCC19111 but not against Gram‐negative bacteria except Pseudomonas fluorescens ATCC11251. Inactivation of bacteriocin‐like activity by α‐chymotrypsin, trypsin, and papain was highly significant (P < 0.001). The BLS was found to be stable under a pH range from 3 to 9 and at temperatures up to 75°C for 60 min, but it lost activity after being autoclaved at 121°C for 15 min. The optimum production of BLS by B. licheniformis H1 was obtained at a temperature of 55°C. Sodium dodecyl sulfate – polyacrylamide electrophoresis analysis of concentrated partially purified supernatants collected after resting the bacterial cells at 55°C revealed a bacteriocin‐like protein with a molecular mass of approximately 3.5 kDa. This study is the first report of a BLS from thermophilic B. licheniformis with an animal compost origin.     

高寒冷凉地区食用菌菌糠再利用研究

以双孢菇2796、鸡腿菇4号为试材,利用平菇、金针菇菌糠栽培双孢菇、鸡腿菇并进行羔羊育肥研究.结果表明:菌糠代粪肥栽培,双孢菇菌糠的添加量40％为最优;菌糠替代玉米芯或棉籽壳等生产主料栽培鸡腿菇添加20％～40％的菌糠和对照相比降低成本18％～35％,而产量仅下降9.6％～16.8％;菌糠饲料替代粗粮育肥羔羊菌糠添加20％育肥效果明显,增重率较对照高13.7％,毛体重较对照高3.2 kg,羔羊胴体重比对照组羔羊提高1.79 kg,屠宰率较对照提高2.2％.     

不同秸秆还田方式对红壤性质及花生生长的影响

通过田间小区试验研究化肥配合不同秸秆还田方式对红壤养分、生物学特性和作物生长的影响。结果表明,与其他(NPK、NPKD1、NPKD2)处理相比,氮磷钾化肥配合秸秆直接还田(NPKJG)处理土壤碱解氮降低了7.88%~31.37%,速效磷降低了7.72%~23.81%。各处理土壤脲酶活性在花生的生长期间先降低后升高,而转化酶活性先升高后降低(除NPK处理的转化酶活性持续降低外)。氮磷钾化肥配合Fe SO4促腐秸秆堆肥还田处理(NPKD2)提高了土壤脲酶活性26.14%,而配合碱渣促腐秸秆堆肥处理(NPKD1)提高了土壤转化酶活性66.13%。氮磷钾化肥配合Fe SO4促腐秸秆堆肥处理土壤微生物生物量碳含量较高,且提高了花生各农艺性状指标和产量。