牧草收割机械的现状和发展趋势

针对浙江省牧草畜牧业和草坪种植业的发展,分析了国内外草业收割机械的现状以及浙江省发展牧草收割机械的机遇,并提出浙江省牧草收割机械应向价格低廉、与已普及的农机具配套使用、适合小田块和丘陵地区作业的牧草收割机械方向发展,认为研制一种既能适用于牧草收割与荒地杂草的整理又能适用于绿化草坪的维护和修剪的中小型割草机是十分必要的.     

莆田市城厢区农民田间学校发展现状、存在问题及对策

总结了莆田市城厢区农民田间学校发展现状,阐述了主要经验做法,指出了存在的不足,并提出了推动农民田间学校发展的政策措施建议。     

Rice-residue biochar influences phosphorus availability in soil with contrasting P status

ABSTRACT

Thermo-chemical conversion of crop residues to produce biochar is an emerging strategy in the context of sustainable phosphorous (P) use and residue management. An incubation study for 90 d was conducted to investigate the effects of rice-residue biochar (0, 10, 20 and 40 g kg^?1) in combination with inorganic-P (KH₂PO₄) (0, 25 and 50 mg kg^?1) on phosphorous availability in medium- and high-P status soils. Increasing biochar addition rates alone or in combination with inorganic-P resulted in a significant increase in P pools, i.e. plant available P or Olsen-P (from 8 to 132 mg kg^?1 in medium-P and 15 to 160 mg kg^?1 in high-P soils), microbial biomass P and various mineral-bound inorganic-P fractions in the order (Ca-P > organic-P > Al-P > loosely held/soluble-P > Fe-P > reductant soluble-P). Further, lower phosphatase activity (19–50%) with increasing rates of biochar addition in both soils elucidates the ability of biochar to act as a long-term source of available P in the experimental soils. The results demonstrate that rice-residue biochar can directly or indirectly enhance the status of available P in soils and hence can be used as a beneficial amendment to meet the crop P demand.     

施用蛋鸡粪的龙眼园土壤质量现状评价

本文调查了蛋鸡养殖场粪便产生量及处理利用现状等基本资料,选点采集养殖场配套龙眼园的土壤样品,通过分析测定有机质、全氮、全磷、铜、锌等指标,探讨了施用蛋鸡粪对龙眼园土壤质量的影响,并对龙眼园土壤环境现状进行评价。结果表明,该养殖场龙眼园土壤粪便当量负荷为19.14t·hm-2,未超过以氮计的土壤粪便当量负荷警戒值。四个季节施用蛋鸡粪的龙眼园土壤中有机质、全氮、全磷、铜、锌等指标均高于未施用蛋鸡粪的橡胶园土壤,但无显著差异;施用过蛋鸡粪的龙眼园土壤有机质、全氮、全磷、铜、锌全年平均含量分别为18.71g·kg-1、0.97g·kg-1、0.79g·kg-1、19.65mg·kg-1和43.05mg·kg-1,均显著高于未施用过蛋鸡粪的橡胶园土壤。四个季节龙眼园土壤和橡胶园土壤铜、锌单项污染指数均小于1,属于安全级别。由于龙眼园施用的蛋鸡粪仅占养殖场蛋鸡粪产生总量的2%,而且采用直接施用鲜鸡粪的方式,因此仍存在环境污染的隐患。本文所得结果可为评估蛋鸡养殖场环境污染风险及与果园结合的蛋鸡养殖模式的合理性提供依据。     

马铃薯的钾素需求及营养诊断

了解马铃薯的钾素营养特点是马铃薯养分管理的基础,综述了马铃薯钾素营养的研究进展,并提出了进一步研究的方向。尽管文献报道的马铃薯需钾量存在差异,但已有的研究结果表明,马铃薯是需钾量较大的作物,其对钾素的需求多于其他元素。而且与小麦等作物相比,马铃薯的钾素营养效率较低。已有的研究还证实土壤交换性钾含量与马铃薯产量的关系并不稳定,仅依靠土壤测试制定钾肥施用方案存在较大的误差,因而马铃薯钾素营养状况诊断并依此指导生育期钾肥施用就显得必要。业已发现叶柄钾浓度能很好的反映马铃薯植株的钾素营养状况,对土壤供钾高度敏感,与块茎产量存在很好的数量关系,因此,用于指导马铃薯施肥的叶柄的临界钾浓度被不同研究人员确立,但干重基础的叶柄钾浓度指标指导施肥实践的时效性较差,这意味着简便快速的诊断方法有待建立。     

Species composition of arbuscular mycorrhizal fungi in two mountain meadows with differing management types and levels of plant biodiversity

Species composition of arbuscular mycorrhizal fungi (AMF) was analysed in two differently managed mountain grasslands in Thuringia (Germany). Arbuscular mycorrhizal fungi were studied in the roots of 18 dominant plant species from a total of 56 (32%). Additionally, spores of AMF were isolated from soil samples. Arbuscular mycorrhizal fungi species composition was analysed based on 96 sequences of the internal transcribed spacer of the nuclear ribosomal DNA, 72 originated from mycorrhizal roots, and 24 originated from AMF spores. Phylogenetic analyses revealed a total of 19 AMF species representing all genera of the Glomeromycota except Scutellospora and Pacispora. Despite a different farming intensity, resulting in remarkable differences concerning their plant species diversity (27 against 43 plant species), the diversity of AMF was found to be similar with 11 species on the intensively farmed meadow and ten species on the extensively farmed one. Nevertheless, species composition between both sites was clearly different. It thus seems likely that the AMF species composition, but not necessarily the species number, is related to above ground plant biodiversity in the system under study.     

茶黄素研究进展

本文综述说明了茶黄素的来源,结构,功效及研究的进展。     

我国甘蔗产业化现状浅析

从甘蔗自然属性、种植地域分布、品种、种植模式等农艺角度,以及甘蔗机械收获方式和甘蔗收获机械等农机角度,对我国甘蔗产业现状进行全面分析,指出甘蔗产业在我国糖业发展的重要地位,且甘蔗收获机械化是甘蔗机械化生产中最薄弱环节。针对我国目前甘蔗收获现状,对制约甘蔗机械收获的因素进行细致分析,并从农艺因素、农机因素、加工因素、环境因素和社会因素等5个方面进行归类提炼,对甘蔗收获机械化进行了展望。     

花生分段收获机的应用现状及进展分析

花生分段收获机已在花生收获中发挥了重要作用,但许多人对其认识不强,没有体会到花生分段收获机在花生收获中的重要性,严重阻碍了花生分段收获机的推广。为了推广花生分段收获机,提高花生收获的效率,介绍了国内外花生分段收获机的应用现状,着重介绍了几种典型的花生分段收获机的特点及其相关参数,并分析了我国花生分段收获机存在的问题以及对未来的展望。     

小区播种机的研究现状及发展方向

种子的质量是保证粮食丰产丰收的根本,小区播种机的性能又是新品种培育的保证。为此,就当前国内外小区播种机的发展现状及我国小区播种机现阶段遇到的问题进行了分析,并对小区播种机排种器等部件进行了重点介绍,最后对我国小区播种机的发展方向进行了展望。