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1.
为了解决春玉米种植时种子浪费严重、地膜烧苗、施肥落后等技术难题,研制了玉米覆膜精播多功能一体化播种机,并对玉米覆膜精播多功能一体化播种机整机构造、工作原理以及关键部件进行研究,提供了玉米精密播种机械的主要技术参数,并在试验田进行了播种田间性能测试试验,以2FBJD-2(机械式播种)为对照。结果表明:该机整体结构合理,播种性能优,播种速度快;平均播种深度为3.52 cm,没有过深或晒种现象,与对照相比,比对照深0.20 cm,差异显著;株距合格率为93.80 %,重播率9.20%,漏播率2.60%,播种均匀性较好;覆膜质量高,破损率基本为0;施肥的稳定性和各行一致性效果较好;出苗率高达95.60%,较对照91.80%高3.80%。 收获后测产表明,该机械播种的田间地块平均产量达12934.50 kg/hm2,较对照产量11473.40 kg/hm2高12.70%。该机能够一次性完成平地、覆膜、施肥、打孔、播种、覆土、镇压等多项作业,降低劳动强度,提高工作效率,节约成本,基本能够满足玉米农艺要求。  相似文献   
2.
Farmland bird declines in Europe are well documented. In the UK, agri-environment schemes are key mechanisms for reversing the declines of birds and other farmland biodiversity, but recent reviews suggest that wet habitats might be a gap in provision by these schemes. Important resources provided by wet habitats include: (i) damp soil, for probing species; (ii) permanent water to provide water-dependent invertebrates, as a source of food; (iii) bare or sparsely vegetated ground in the draw-down zone, to improve access to food; (iv) rank emergent vegetation for nesting. However, wet habitats have been lost from farmland as a result of loss of ponds and filling of ditches, as well as the effective removal of water from fields by surface run-off, itself affected by soil compaction, and extensive under-field drainage. The efficient removal of water from fields can cause problems downstream, both through flooding, and diffuse pollution. Regular farmland pollutants include pesticides, nitrogen, phosphorus and sediment, leading to environmental problems such as eutrophication and reduced quality of drinking water. Major new political instruments, such as the Water Framework Directive, will aim to reduce the impact of this diffuse pollution from agriculture. A variety of solutions to diffuse pollution, such as conservation tillage, buffer strips at field edges, and small constructed wetlands, could simultaneously provide some of the resources required by farmland birds. We suggest that future agri-environment schemes, to be truly multifunctional, could focus on bringing these diverse objectives together.  相似文献   
3.
锁秀  何昉 《广东园林》2012,34(3):20-23
通过对珠三角绿道网规划的解读,阐述了珠三角绿道网概念的由来,以及绿道在自然理念的延伸、人文生态价值的演绎和多功能并存等三方面的价值塑造,揭示了绿道独具中国"道者,自然之理"之大智慧,以及引领理想城市生活、弘扬新广东精神等方面的精神内涵。  相似文献   
4.
在对多功能采伐机进行结构分析的基础上,通过合理简化,用拉格朗日方法建立了5自由度动力学振动方程,在考虑路面随机激励和脉冲激励的情况下,应用Matlab/Simulink软件完成整机振动模型的仿真计算,进行了行驶平顺性仿真分析。预测多功能采伐机具有良好的行驶平顺性,为多功能采伐机设计时减振系统的设计提供了依据。  相似文献   
5.
多功能轻小型灌溉机组是一种新型灌溉机组,具有喷灌和软管灌溉两种灌水方式,满足了不同作物在不同生育期对水分的要求。该喷水车安装有高度调节装置,始终使灌水器处于最佳灌水高度,克服了受风影响较大的弱点,减少了灌溉水分的漂移损失,提高了灌水均匀度和利用效率。在试验室内通过对该机组水力性能试验研究,结果表明,该机组在喷灌方式下灌水均匀度要好于软管灌溉;机组行进速率在不同档位下随压力增大而增加。  相似文献   
6.
农业文化遗产保护: 生态农业发展的新契机*   总被引:10,自引:4,他引:6  
农业发展在通过科学技术进步和土地集约化利用取得巨大成绩的同时,也造成了生态与环境问题的日益加剧。与之对应的是一些传统地区的传统农耕方式在适应气候变化、供给生态系统服务、保护环境、提供多种产品等方面具有独特的优势。人类逐渐认识到保护这些传统的农业技术以及重要的生物资源和独具特色的农业景观的重要性。经过近30年的实践和发展,中国生态农业发展进入瓶颈期。而农业文化遗产的保护,不仅为现代高效生态农业的发展保留了杰出的农业景观,维持了可恢复的生态系统,传承了高价值的传统知识和文化活动,同时也保存了具有全球重要意义的农业生物多样性,为现代高效生态农业的多功能发展提供了物质基础和技术支撑。最后本文从生产功能、生态功能及文化功能角度对生态农业多功能发展进行了初步探讨。  相似文献   
7.
The loss of connectivity of forest landscapes is seriously hindering dispersal of many forest-dwelling species, which may be critical for their viability and conservation. In this context, explicitly incorporating connectivity considerations is an important challenge in current forest planning and management, but as yet there is a lack of operative methods for appropriate decision making in this respect. We describe a new methodology based on graph structures and a habitat availability index (integral index of connectivity) that integrates forest attributes (like habitat quality) and network connectivity in a single measure. We apply this methodology to examine the connectivity of the highly fragmented habitat of capercaillie (Tetrao urogallus) in Catalonia (NE Spain), where the threatened status of this forest bird species calls for landscape-level forest planning solutions. We analyse data on the distribution of capercaillie forest habitat at 1 km spatial resolution obtained from the recent Catalan Breeding Bird Atlas. We determine the functionally connected regions existing within its habitat distribution and identify the forest habitat areas that are more important for the maintenance of overall landscape connectivity for this species. Based on these results, we provide recommendations on certain critical public forests where management oriented to the conservation of capercaillie habitat is more necessary. These results highlight the potential and practical interest of the proposed methodology for successfully integrating landscape connectivity in broad scale forest planning.  相似文献   
8.
研究了3种不同薄膜覆盖大棚内小气候因子的变化.研究结果表明,在不同测定日期中,覆盖不同塑料薄膜大棚的棚内外日平均气温和日平均地温变化相似,转光膜1的保温性能优于转光膜2和无滴膜;转光膜1的透光率高于转光膜2和无滴膜,无滴膜的透光率则略高于转光膜2.不论晴天还是阴天,转光膜,均表现出较好的保温与采光性能,而且使用这3种农膜后.大棚内温度和光强变化规律相似.  相似文献   
9.
Transdisciplinary practice is considered essential for achieving multifunctional landscapes in cities. But we lack empirical evidence and frameworks that could help us clarify its role and scope. This study seeks to offer empirical evidence by comparing the role of transdisciplinary practice in two projects delivering multifunctional landscapes. What disciplinary dynamics played out in these projects, and what strategies did practitioners use to bring actors together? Using semi-structured interviews, and document analysis, we found different disciplinary dynamics and strategies at play across preparation and transition project phases linked by a window of opportunity. Transdisciplinary practices featured mainly in the preparation project phase, which was characterized by exploring strategies and establishing leaderships and networks that integrate and build knowledge. During this phase, practitioners applied strategies to highlight the relevance of environmental problems, and to get support from different sectors and audiences. Once practitioners found consensus on common targets and obtained support, decision-making processes became less complex, and time became a priority. In the transition phase, improvisation and flexibility were needed to manage problems in different domains. In this phase, transdisciplinary practice ceased to be relevant, and multidisciplinary, monodisciplinary, and interdisciplinary practices dominated, depending on the expertise required to fulfil project objectives and the need for people to work concurrently to meet specific time frames. Here, practitioners applied strategies, but these were carefully chosen for specific audiences to avoid delays.We conclude that diverse disciplinary approaches are used to achieve multifunctional landscapes, and that transdisciplinarity is not the only path to success. Contextual factors will determine the disciplinary approaches needed across all phases. Practitioners wishing to use transdisciplinary practices beyond the initial project phase will require flexibility with regard to timing, concrete guidelines and formal institutional commitment to this approach.  相似文献   
10.
多功能拌种剂在水稻节水抗旱上的应用效果研究   总被引:1,自引:0,他引:1  
研究了农业抗旱节水用多功能拌种剂对双季晚稻生理性状、水分吸收、养分积累和产量形成的影响,结果表明:农业抗旱节水用多功能拌种剂具有促根壮秧、增穗重粒、节水增产等作用。  相似文献   
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