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1.
不同水肥一体化方式和施肥量对烤烟生长、氮磷钾利用及烟叶产质量的影响 总被引：1，自引：0，他引：1
《灌溉排水学报》2019,(8)
【目的】寻找烤烟适宜的水肥一体化方式。【方法】通过田间试验研究了2种水肥一体化方式(滴灌施肥和浇灌施肥)和2种氮肥用量(100%推荐量和80%推荐量)对烤烟生长、氮磷钾利用及烟叶产量的影响。【结果】不同水肥一体化方式对烟株氮素累积量和利用率无显著影响(P>0.05),对磷素累积量和利用率均有显著影响(P<0.05),对烟株钾素累积量和利用率均有极显著影响(P<0.01),对烤烟旺长期最大叶宽和最大叶面积有极显著影响(P<0.01),对烤烟产量和产值有显著影响(P<0.05)。与滴灌施肥相比,浇灌施肥处理磷素累积量和利用率分别提高了21.1%～21.2%和20.9%～43.0%,钾素累积量和利用率分别下降了15.1%～19.6%和47.5%～49.1%,最大叶宽和最大叶面积分别减小了17.4%～22.4%和22.1%～24.4%,烤烟产量和产值分别下降了12.7%～16.2%和7.7%～20.2%;施肥(氮)水平对烟株氮素累积量有显著影响(P<0.05),对磷素和钾素累积量无显著影响(P>0.05),对烤烟农艺性状及产量均无显著影响(P>0.05)。【结论】与滴灌施肥相比,浇灌施肥促进了烤烟对磷素的吸收,但不利于氮素和钾素的累积利用。相对而言,减氮滴灌促进了烤烟对氮磷钾的吸收利用,并有利于烤烟产质量的形成和农田养分投入的减控,是更为科学合理的抗旱水肥一体化方式。 相似文献
2.
沙棘,亚欧种,1753年植物学家Karl von Linné发现了沙棘并分类为"植物志"的第1023种.沙棘(Hippophae rhamnoides)被认为是希腊语"闪闪发亮的马"的语源.罗马尼亚的专家论证了沙棘对动物健康的影响,特别是皮肤方面,沙棘还有着消除肠内病菌的作用. 相似文献
3.
The plant module of the EPIC model (Erosion Productivity Impact Calculator) has been modified to simulate the effects of water and nitrogen (N) stress on biomass production and grain yield, taking account of the sensitivity of the crops to water and N stress during the course of their developmental cycle. This French version of the model, EPICphase, was validated with maize (Zea mays L.), sunflower (Helianthus annuus L.), sorghum (Sorghum bicolor L. Moench), soybean (Glycine max L.), and winter wheat (Triticum aestivum L.) over 9 years, using experimental data from a long-term cropping system experiment carried out at three levels of cropping intensity. The results have been compared with those from a normal version of EPIC. The two versions use the same input files. The results show that EPIC overestimates crop production by comparison with the measured data, notably under conditions of severe moisture stress. The additional crop parameters introduced into EPICphase concern the water extraction capacities peculiar to each crop, the division of the growth period into four phases, with adjustments to the conversion efficiency of intercepted radiation into biomass, and the drought adaptation of sunflower and soybean. Finally, the sensitivity of the harvest index to water and N stress has been introduced for each phase of growth. These refinements have led to simulations very close to the measured values. Comparison of results from the two versions was done by means of a statistical study of mean biomass production and grain yield, standard deviations, root mean square error, regression lines, and R2 values. 相似文献
4.
Dang K. Nhan Le T. Phong Marc J.C. Verdegem Le T. Duong Roel H. Bosma David C. Little 《Agricultural Systems》2007
Promotion of integrated aquaculture with agriculture, including crops and livestock (IAA-farming), requires consideration of both bio-physical and socio-economic contexts. The major factors influencing the adoption of IAA-farming by households at three sites in the Mekong delta were identified. Special attention was given to the multiple roles ponds play in IAA-farming systems. Information was collected through semi-structured interviews and discussions with focus groups and key individuals. Data were analyzed using multivariate factor analysis, analysis of variance or participatory ranking methods. Three major IAA-systems were identified: (1) low-input fish farming integrated with intensive fruit production (system 1), (2) medium-input fish farming integrated with less intensive fruit production (system 2), and (3) high-input fish farming integrated with less intensive fruit production (system 3). System 1 was commonly practised in a rural fruit-dominated area with fertile soils, while systems 2 and 3 were more evident in peri-urban rice-dominated areas with less fertile soils. In the study area, only 6% of poor farmers adopted IAA-farming, while this was 42% for intermediate and 60% for rich households. Richer farmers tended to intensify fish farming and seek a more commercial orientation. The major factors why farmers did not start aquaculture were the inappropriateness of technology, insufficient land holding or poor access to extension services, limited farm management, and through a fear of conflicts associated with pesticide use on crops. The main motivations for practising IAA-farming included increased income and food for home consumption from the available farm resources while reducing environmental impacts. Further improvements to IAA-systems can be realized by strengthening nutrient recycling between different IAA-system components while enhancing farming output and safeguarding the environment. 相似文献
5.
To evaluate the hydraulic performance of subsurface collector drains and to study the relationships between discharge rates, crop patterns, and the salinity of drainage water, subsurface drains were monitored in different parts of the Nile Delta and Valley.Actual discharges were much smaller than design discharges. Also, overpressure in the pipes occurred frequently, indicating too small a capacity in the design. From research in one pilot area, it was concluded that if construction methods and materials are not improved, the roughness factor in the design should be increased by 100% to allow sufficient capacity.The cultivation of rice increases discharges. Salinity of drainage water is higher in winter than in summer, and higher in the north of the Delta than in the south. 相似文献
6.
A field study was conducted in the semiarid region of northern Sudan to investigate the effects of variable irrigation on
the growth, yield, and water use efficiency (WUE) of alfalfa (Medicago sativa L.). Treatments were 65 mm of water applied every 7 days, 80 mm of water applied every 10 days, or 104 mm of water applied
every 13 days. The heavy, infrequent irrigation reduced stem height, stem density, leaf area index (LAI), total biomass production,
and the WUE of alfalfa plants. Maximum yields for six harvests were 15.3, 12.9, and 11.2 ton ha–1 and the WUE values were 0.12, 0.10, and 0.08 ton ha–1 cm–1 for the frequent, less-frequent, and infrequent irrigation regimes, respectively. In all the treatments, alfalfa dry matter
yield was positively correlated with stem height and LAI. The relationship between dry matter yield and total water use was
a linear function (R
2=0.99), regardless of the irrigation treatment. Alfalfa growth, yield, and WUE remained high during the relatively cool months
and declined during the hot period under the three water regimes. It was concluded that alfalfa grown under semiarid conditions
should be watered lightly and frequently to attain high yields and high WUE.
Received: 19 February 1996 相似文献
7.
文章详细阐述了微耕机的发展历程,并分析了制约我国微耕机发展的原因。在此基础上,笔者结合自身多年的实践经验,探索、分析了正确选购、使用和保养维修微耕机的方法。 相似文献
8.
一、加强农机推广体系建设
“十五”期间，农业及农村经济得到了飞速发展，特别是党的十六大以来，党中央和国务院高度重视“三农”工作，确立了统筹城乡发展方略，制定了“多予、少取、放活”和“工业反哺农业、城市支持农村”重要方针，提出了建设社会主义新农村的重大历史任务，形成了全社会美山农业、关注农村、关爱农民的良好氛围。在这期间，农机化发展和农机化新技术、新机具推广应用得到了高度重视。2004年出台了《农业机械化促进法》，从2004年开始，中央连续下发三个“一号文件”，明确提出了“加大农机具购置补贴政策的实施力度”，“改革传统耕作方法，发展保护胜耕作”，“加快改革农业技术推广体系，明确农技推广机构公益性职能”， 相似文献
9.
王燕 《国际沙棘研究与开发》2017,(11)
随着社会经济的发展,生态环境问题愈加突出,为了落实科学发展观,贯彻"绿水青山就是金山银山"的重要思想,做好河湖库塘清淤工作中淤泥处理显得尤为重要.大规模清淤迅速开展,短时间内淤泥量大幅增加.由于淤泥处置能力不足,需借地堆放,且部分淤泥存在污染,堆放隐患严重,因地制宜,科学处置是当前清污(淤)工作的一大难题.本文以浙江省河湖库塘清淤工作中淤泥为例,分析淤泥处置中出现的问题,并提出切实可行的处置方式,以便相关人士借鉴和参考. 相似文献
10.
保护性耕作与病虫草害综合防治 总被引：1，自引：0，他引：1
一、保护性耕作技术发展现状保护性耕作是从免耕技术发展起来的一项新的耕作技术体系。20世纪30年代,针对过度耕种引发沙尘暴、土壤质量下降的问题,美国土壤保护局提出保护农田土壤对策并推出了保护性耕作技术。在上世纪80年代以前,受配套农机具及相关技术和传统观念的限制,保护性耕作在美国、加拿大等国的推广应用十分缓慢。1985年美国国会通过了食品安全行动计划,制定了推广保护性耕作相应的贷款、灾害赔付政策和联邦农作物保险法,同时,随着保护性耕作配套农机具的推出和栽培、植保技术的发展,特别是价格低廉的除草剂出现,使保护性耕作应… 相似文献
11.
12.
随着农村经济的不断发展,农用拖拉机被广泛使用.由于拖拉机是在较为恶劣的环境中进行作业,且农民在使用拖拉机的过程中缺少科学合理的维修、调整和保养,使拖拉机很容易出现故障,不仅影响了生产效率,同时还大大减少了拖拉机的使用寿命,增加成本.文章根据现代农用拖拉机维修保养的内容,从而分析拖拉机的维修、调整和保养技术,为今后农民对拖拉机的使用能够提供相应的借鉴和参考. 相似文献
13.
住宅郊区化是发达国家城市居住区位变化的共同趋势.我国城市政府应该重点发展城郊普通商品住宅,在规划布局方面应体现统一规划、组团式布局、产业协调发展、节约土地等原则.在建设及管理方面应做到:成片集中开发,完善现代化交通系统,合理的市场定位,强化小区物业管理和服务. 相似文献
14.
15.
Response of corn, grain sorghum, and sunflower to irrigation in the High Plains of Kansas 总被引：1，自引：0，他引：1
Groundwater is being mined in much of the irrigated area of the central and southern High Plains of the USA. Profits and risks inherent in irrigation management depend on the association between crop yield and level of water application. Research was conducted over a 14 year period (1974–1987) to establish the yield vs. water application relationships of corn, grain sorghum, and sunflower. The research was located near Tribune, Kansas, USA on a Ulysses silt loam soil. Plots were level-basins to which water was added individually through gated pipe. Irrigation studies of the three crops were located adjacent to each other. Irrigation treatments were arranged in completely randomized blocks with three replications. As total irrigation amount increased from 100 to 200, 200 to 300, and 300 to 400 mm, sunflower yield increased by 0.53 Mg ha−1, 0.43 Mg ha−1, and 0.37 Mg ha−1, respectively. Corn outyielded grain sorghum at total irrigation amounts of 345 mm and above. Yield increase over continuous dryland was greater in corn than in grain sorghum at total irrigation amounts above 206 mm. Therefore, if grain mass is the consideration, grain sorghum is a better choice than corn at less than 206 mm of irrigation, whereas corn is a better choice than grain sorghum at more than 206 mm of irrigation. 相似文献
16.
美国是个农业发达的国家,农业合作社在其农业发展过程中扮演着重要的角色。本文主要针对美国新一代合作社的特征、绩效与问题进行了深入的研究。由此得出的一些启示对我国农业及合作社发展具有重要的借鉴意义。 相似文献
17.
Summary A factorial experiment which examined the effects of sowing date, cultivar and irrigation frequency on the growth and grain yield of irrigated wheat was conducted at Narrabri, New South Wales. Irrigation scheduling was based on morning values of leaf water potentials (l): plots were watered when l, had fallen to either –0.8 MPa or –0.4 MPa or were not irrigated during the season.Maximum leaf areas, tiller numbers and total dry matter production were increased by more frequent irrigation, but subsequent tiller death and leaf senescence were generally not reduced by increasing watering. A delay in sowing from 23 June to 23 July reduced yields by 20%, on average. More frequent irrigation increased yields at both sowing dates, but a high protein, locally bred wheat (Songlen) responded less than a cultivar derived from the CIMMYT program (WW 15). The highest yield for Songlen was 570 g m–2 which was lower than the highest yield for WW 15 (730 g m–2); both were obtained from the –0.4 MPa treatment sown on 23 June. Compared with irrigated wheat grown in Mexico or southern New South Wales, dry matter production after anthesis at Narrabri was low. It was suggested that high temperatures after anthesis may limit post-anthesis productivity and subsequently, grain yields. The results of this experiment suggested that yields of irrigated wheat in the lower Namoi Valley can be improved through better irrigation management and varietal improvement, but the magnitude of this response may be limited by high spring temperatures. 相似文献
18.
有学者认为三国有共同的语言,而另一些学者认为三国语言是不同的。究其原因是前者只是凭借主观感觉甚至个人喜好进行遐想,这虽然本身不是学术问题,但是需要以学术的视角和方法加以研究和解决;而后者是历史性地考虑问题,把历史及历史的语言放在里面加以考虑,更全面更真实地反映历史实际,这是更可取的。 相似文献
19.
Effect of saline water irrigation and manure application on the available water content, soil salinity, and growth of wheat 总被引：4，自引：0，他引：4
Good water management combined with appropriate soil management is necessary for sustainable crop production in drylands. A pot culture experiment was conducted using sand dune soil under greenhouse conditions to evaluate the response of wheat (Triticum aestivum L.) to the application of farmyard manure (FYM) or poultry manure (PM), and irrigation with water at two salinity levels (0.11 and 2.0 dS m−1) and two irrigation intervals (daily and every second day). The manure was applied at a rate of 20 Mg ha−1. The soil water content, measured 1 h before every irrigation, showed that soil treated with PM retained more water than that treated with FYM, while the control (no manure) contained the least water. FYM treatment resulted in 78 and 21% higher dry matter yield compared to the control and PM treatments, respectively, under daily irrigation using good-quality water. The increase was 29 and 55%, respectively, when saline water was used for daily irrigation. A similar trend was observed with the alternate day irrigation treatment; FYM gave the highest dry matter yield. The number of tillers and plant height showed that FYM was better than PM, which in turn was better than the control under irrigation with good-quality water regardless of the irrigation interval. When water of the highest salinity was used for irrigation, FYM was still always the best, but the control was now better than the PM treatment. The electrical conductivity of the soil measured at the end of the experiment was slightly higher with PM, as compared to the FYM and control treatments. A significant interaction between irrigation water quality and manure application was observed, affecting plant growth. PM aggravated the adverse affect of saline water on plant growth by increasing soil salinity. 相似文献
20.
农机具的检修是提高农业机械安全生产的重要手段。当前有不少机手对农机具的检修没有足够的重视,造成机具技术状态差,设备老化,甚至达到报废期还在工作,严重影响了农业生产,耽误了农时,这就要求农机管理人员随时要对农机具进行检查、督促、指导检修。对于大中型农用车,特别是链轨拖拉机要进行强制性修理。 相似文献