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为了解凤城市耕地土壤的肥力现状,测定土壤中有机质、碱解氮、有效磷等养分含量,并对全市土壤肥力水平及变化规律进行分析。结果表明：碱解氮含量呈平稳上升趋势;有机质和有效磷含量上升幅度较大;速效钾含量略有上升;pH值略有上升。 相似文献
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王平 《农业机械化与电气化》2014,(11):3-5
为掌握凤城市耕地土壤的pH值状况,对比分析近25 a的pH值土壤变化情况。结果表明：1980—2007年,凤城市处于酸性的三级耕地面积有大幅度增加,总体增加了15642．6 hm2,主要集中在白旗镇和边门镇;pH处于弱酸性和中性水平的四级和五级耕地面积大幅下降,主要集中在石城镇、边门镇等地。 相似文献
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1耕地土壤养分综述根据全市的测定结果表明,全县耕地土壤有机质平均含量为25．44g／kg;全氮平均含量为0．89g／kg;碱解氮平均含量为101．2mg／kg;有效磷平均含量为37．92mg／kg; 相似文献
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为摸清朝阳市龙城区的耕地质量状况,选取有代表性的土壤样品进行pH值、有机质、全氮、速效钾等16项养分指标的测试分析。分析结果表明:朝阳市龙城区土壤有机质含量稍缺,碱解氮含量较缺,有效磷和速效钾含量丰富;中量元素含量不缺;有效硼和有效铁含量缺乏,其他元素含量不缺;旱田土壤肥力高于果园土壤。 相似文献
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<正>沧县对所取3300个土壤样品进行了速效N、P、K、有机质、PH值等土壤养分的化验分析,取得有效数据40000余个,结合田间肥效试验结果、农户调查结果及本县实际情况,制定了沧县冬小麦、玉米施肥指标体系,技术指标规范,应用效果明显,基本涵盖了本县不同作物,不同生产水平的需要,对指导我县农业生产具有重大意义。1沧县土壤养分状况1.1全县耕地土壤有机质平均值在11.6g/kg,属中等偏下水平(10g/kg为低含量,10~25g/kg为中含量,25g/kg以上为高含量)。含量变幅在 相似文献
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为了解彰武县的耕地、果园土壤肥力状态,在全县采集土壤样品161个,对有机质、全氮、碱解氮、有效磷、速效钾等16项土壤养分指标进行测试分析。结果表明：彰武县土壤氮素严重缺乏,磷素含量中等,钾素含量丰富;除钙素外,其他中量元素基本不缺;微量营养元素硼和钼缺乏,其他很丰富。 相似文献
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刘彦 《农业机械化与电气化》2014,(6):12-13
为合理利用土地及保护农田生态平衡,在辽中县不同类型耕地抽取170个土壤样品,进行土壤养分指标的测试与分析。试验结果表明：辽中县耕地土壤有机质含量稍缺,碱解氮和速效钾含量中等,有效磷含量很丰富;中微量元素含量均很高,能够满足作物正常生长需要：耕地总体肥力较高。 相似文献
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张宏成 《农业机械化与电气化》2009,(6):18-21
宽甸县推广测土配方施肥以来,取得了良好效果。为进一步推进测土配方施肥工作,宽甸县对全县耕地土壤养分含量进行测量。测量结果表明：宽甸县耕地土壤有机质、碱解N和有效P含量上升;速效K含量虽然上升,但未达到1980年水平;耕地土壤pH值呈现中性化趋势。根据耕地土壤养分含量,通过拟合土壤养分与产量的方程,建立宽甸县耕地养分指标体系,找出土壤养分与作物产量之间的关系,并提出合理的施肥建议。 相似文献
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Overland water and salt flows in a set of rice paddies 总被引：1，自引：0，他引：1
E. Playn O. Prez-Coveta A. Martínez-Cob J. Herrero P. García-Navarro B. Latorre P. Brufau J. Garcs 《Agricultural Water Management》2008,95(6):645-658
Cultivation of paddy rice in semiarid areas of the world faces problems related to water scarcity. This paper aims at characterizing water use in a set of paddies located in the central Ebro basin of Spain using experimentation and computer simulation. A commercial field with six interconnected paddies, with a total area of 5.31 ha, was instrumented to measure discharge and water quality at the inflow and at the runoff outlet. The soil was classified as a Typic Calcixerept, and was characterized by a mild salinity (2.5 dS m−1) and an infiltration rate of 5.8 mm day−1. The evolution of flow depth at all paddies was recorded. Data from the 2002 rice-growing season was elaborated using a mass balance approach to estimate the infiltration rate and the evolution of discharge between paddies. Seasonal crop evapotranspiration, estimated with the surface renewal method, was 731 mm (5.1 mm day−1), very similar to that of other summer cereals grown in the area, like corn. The irrigation input was 1874 mm, deep percolation was 830 mm and surface runoff was 372 mm. Irrigation efficiency was estimated as 41%. The quality of surface runoff water was slightly degraded due to evapoconcentration and to the contact with the soil. During the period 2001–2003, the electrical conductivity of surface runoff water was 54% higher than that of irrigation water. However, the runoff water was suitable for irrigation. A mechanistic mass balance model of inter-paddy water flow permitted to conclude that improvements in irrigation efficiency cannot be easily obtained in the experimental conditions. Since deep percolation losses more than double surface runoff losses, a reduction in irrigation discharge would not have much room for efficiency improvement. Simulations also showed that rice irrigation performance was not negatively affected by the fluctuating inflow hydrograph. These hydrographs are typical of turnouts located at the tail end of tertiary irrigation ditches. In fact, these are the sites where rice has been historically cultivated in the study area, since local soils are often saline-sodic and can only grow paddy rice taking advantage of the low salinity of the irrigation water. The low infiltration rate characteristic of these saline-sodic soils (an experimental value of 3.2 mm day−1 was obtained) combined with a reduced irrigation discharge resulted in a simulated irrigation efficiency of 60%. Paddy rice irrigation efficiency can attain reasonable values in the local saline-sodic soils, where the infiltration rate is clearly smaller than the average daily rice evapotranspiration. 相似文献
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瓦房店市是我国重要的水果生产基地,在国内水果生产领域占有重要地位。随着水果市场化的不断深入,如何满足和适应国内外市场需求成为瓦房店市水果生产的关键问题。从瓦房店市水果生产实际出发,阐述了实施水果生产标准化的必要性,提出了发展水果生产标准化的具体措施。 相似文献
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对引进的谷子新品种金谷子耐旱TG118进行品种比较试验和多点试种。结果表明：该品种抗旱、耐瘠、适应性强,稳产、高产、抗病抗风抗倒伏强,品质优良,粮草兼用,种植简单,省工易管;一般产量在6000kg/hm2以上,比当地主栽品种增产20%以上。最高产量达9450kg/hm2,适于在辽西北地区推广应用。 相似文献
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对《种子法》存在问题的探讨 总被引：1，自引：0，他引：1
李鹏 《农业机械化与电气化》2011,(6):129-130
《种子法》是我国种植业第一部法律。自实施以来,为依法加强种子管理提供了有力的法律支撑,促进我国种子产业发生翻天覆地的变化。但随着依法管理工作的深入和种子产业的快速发展,《种子法》及配套规章的一些问题逐步显现出来。对《种子法》及配套规章存在的问题进行深入分析,对需要进一步补充的章节以及需要调整的内容进行深入探讨,以求更加完善和明确。 相似文献
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About 30 years have passed since the Government of Egypt embarked on implementing a series of large scale drainage projects. At present, about 3.8 million acres have been provided with drainage systems on the basis of systematic pre-drainage investigations and designs. The target is to provide drains in approximately 6.4 million acres in the Nile Valley and Delta.The implementation of the subsurface drainage system is carried out by the public sector and private contractors under direct supervision of governmental regional departments. The implementation process depends on many factors related to the drainage material, machinery, manpower, site requirements, farmers and organizations involved. Problems and constraints are sometimes challenging, however, the annual rate of implementation has gradually increased to 170,000 acre/year.This paper discusses the different aspects involved in the implementation process of drainage systems. The development in materials, machinery and construction technologies will be reviewed. Institutional and management factors are going to be also considered. 相似文献
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在新世纪,面对机遇和挑战,党的十六大把“社会更加和谐”作为全面建设更高水平的小康社会的一个重要目标。中国人素有社会和谐的理想;西方人自古也向往社会和谐;借鉴东西方两种和谐社会思想的经验、教训,构建社会主义和谐社会理论。 相似文献
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Gunter Wriedt Marijn van der Velde Alberto Aloe Fayçal Bouraoui 《Agricultural Water Management》2009,96(5):771-789
We present a pan-European irrigation map based on regional European statistics, a European land use map and a global irrigation map. The map provides spatial information on the distribution of irrigated areas per crop type which allows determining irrigated areas at the level of spatial modelling units. The map is a requirement for a European scale assessment of the impacts of irrigated agriculture on water resources based on spatially distributed modelling of crop growth and water balance. The irrigation map was compiled in a two step procedure. First, irrigated areas were distributed to potentially irrigated crops at a regional level (European statistical regions NUTS3), combining Farm Structure Survey (FSS) data on irrigated area, crop-specific irrigated area for crops whenever available, and total crop area. Second, crop-specific irrigated area was distributed within each statistical region based on the crop distribution given in our land use map. A global map of irrigated areas with a 5′ resolution was used to further constrain the distribution within each NUTS3 based on the density of irrigated areas. The constrained distribution of irrigated areas as taken from statistics to a high resolution dataset enables us to estimate irrigated areas for various spatial entities, including administrative, natural and artificial units, providing a reasonable input scenario for large-scale distributed modelling applications. The dataset bridges a gap between global datasets and detailed regional data on the distribution of irrigated areas and provides information for various assessments and modelling applications. 相似文献
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在介绍粉质仪和拉伸仪结构和原理的基础上,探讨了粉质曲线中吸水率、形成时间、稳定时间、弱化度和评价值等指标与面粉品质的关系,以及如何根据拉伸曲线中面团最大拉伸阻力、延伸度和拉伸曲线面积等指标来评价面团品质,并结合生产实际,概述了粉质仪和拉伸仪在面粉生产中的作用。 相似文献
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车辆ABS控制算法的研究及探讨 总被引：1，自引：0，他引：1
对现代汽车的ABS控制算法作了一些简单的介绍,同时指出了它们的一些缺陷,相应地提出了几种对ABS的其它控制方法并加以探讨,其中着重论述了ABS门限值控制算法中参考车速的确定方法和基于附着系数的控制算法。 相似文献