不同土壤调理剂对水稻吸收重金属强度影响

为研讨土壤调理剂对水稻吸收重金属的影响，探索适宜大田推广的耕地生产障碍修复治理方法，提高受污染耕地质量，实现“边生产，边修复”的目的。在贵州省麻江县开展不同土壤调理剂对水稻吸收重金属强度影响的试验，选用楚戈土壤调理剂、富力邦土壤调理剂、土沃宝土壤调理剂、改性天然矿物材料等4种土壤调理剂，采用空白作对照。试验检测结果为：土壤调理剂处理后，土壤pH值提升率达0.65%～12.03%，土壤中有效镉含量降低10.64%～14.83%，土壤重金属砷含量降低0.4～1.8mg/kg；稻谷中镉含量降低了7.80%～44.07%，硒含量增加为0.004～0.017mg/kg；对水稻产量影响不明显。试验说明在受污染的酸性耕地中施用碱性土壤调理剂，可以提高土壤pH值，降低土壤中重金属砷含量和重金属有效镉的含量，也能减少稻谷对重金属镉的吸收。     

沈阳地区不同利用类型耕地土壤肥力现状评价

采集沈阳地区不同利用类型耕地土壤样品425个,对土壤养分指标进行测试分析。结果表明：沈阳地区土壤有机质、有效磷和速效钾整体上属于丰富水平,全氮属于很丰富水平,土壤有效硅、交换性钙、交换性镁平均含量大于临界值,有效铜、有效锌、有效铁、有效锰属于很丰富水平,有效硼属于中等水平,总体肥力较高。     

宽甸县耕地土壤养分指标体系研究及施肥建议

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。     

磷肥品种与土壤磷素活化系数对栗钙土磷素淋溶的影响

【目的】探究磷肥品种与土壤磷素活化系数(PAC)对栗钙土磷素淋溶的影响。【方法】采集栗钙土农田2种PAC差异较大的土壤,采用土柱模拟试验,研究了施用含P2O5为160 kg/hm2的过磷酸钙(MCP)、磷酸一铵(MAP)、磷酸二铵(DAP)对土壤渗漏液的总磷(TP)、可溶性磷(TDP)动态变化以及淋失量的影响。【结果】栗钙土中存在超过40 cm土层的磷肥淋溶损失,PAC为7.72%的土壤淋溶液初始TP质量分数是PAC为0.86%的土壤的1.91倍;TDP是栗钙土磷淋溶的主要形式,占TP的68.8%～82.9%;PAC较高的土壤施用磷肥显著增加磷素淋溶损失,且磷素淋溶损失量显著高于PAC较低的土壤;PAC较高的土壤中DAP的磷肥淋溶损失显著高于MAP和MCP处理,各磷肥淋溶量不足施磷量的2%。【结论】PAC较高的土壤施用磷肥存在较高的磷淋溶风险,DAP处理在栗钙土中的磷素淋溶损失最大。     

宽旬县耕地土壤养分指标体系研究及施肥建议

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.     

基于高标准农田建设的粮食产能评定分析

高标准农田建设是新时代保护耕地质量和提高粮食产能的重要方式,也是切实落实新型城镇化建设和乡村振兴战略的重要抓手。粮食产能的评估认定依赖于耕地等别评估论证结果,而指定作物选取的分等因素如有效土层厚度、表层土壤质地、土壤盐渍化程度、土壤有机质含量、排水条件、地形坡度、灌溉保证率和灌溉水源等对耕地等别评定具有显著影响。笔者对QS县高标准农田建设产生的新增粮食产能情况进行分析,结果表明,经过高标准农田项目建设,项目区耕地等别可提升1等,预计新增粮食产能3 556 t,研究方法可为同类项目的实施提供必要参考。     

保护性耕作措施对夏玉米产量和水分利用效率的影响

为了研究保护性耕作措施与旱作农田保墒效果之间的关系,采用田问试验与室内精细试验相结合的方法研究其对夏玉米生长产量和水分利用效率的影响.研究结果表明,4种保护性耕作措施都可以提高播种期土壤墒情,0～50 cm土壤水分含量均比对照提高5%以上,而0～20 cm耕作层土壤水分含量可提高7.8%～15.55%;折合产量比对照增产7.17%～17.85%;水分利用效率提高6.36%～14.10%,以浅松覆盖处理增产效果最好,水分利用效率最高.     

抚顺地区实施秸秆粉碎还田的意义及条件

抚顺地区农家肥的年使用量逐年减少,而大量化肥的施用导致当地耕地土壤有机质含量严重下降,氮含量严重超标,磷、钾含量不足,土壤板结,影响作物生长。实践证明,实施秸秆粉碎还田可以增加土地储水量14%～15%,提高水分利用率15%～17%,且1a可增加土壤有机质含量0.04%,还可以把抚顺2/3中低产田改造成高产田,从而提高单位面积产量和减少化肥投入,促进农民增收节支和农业可持续发展,更有利于保护辽宁水源地水质和减少火灾发生。通过分析表明在抚顺地区推广秸秆粉碎还田技术,已具备良好的实施条件。     

抚顺地区实施秸秆粉碎还田的意义及条件

抚顺地区农家肥的年使用量逐年减少,而大量化肥的施用导致当地耕地土壤有机质含量严重下降,氮含量严重超标,磷、钾含量不足,土壤板结,影响作物生长。实践证明,实施秸秆粉碎还田可以增加土地储水量14%～15%,提高水分利用率15%～17%,且1a可增加土壤有机质含量0.04%,还可以把抚顺2/3中低产田改造成高产田,从而提高单位面积产量和减少化肥投入,促进农民增收节支和农业可持续发展,更有利于保护辽宁水源地水质和减少火灾发生。通过分析表明在抚顺地区推广秸秆粉碎还田技术,已具备良好的实施条件。     

西北旱地秸秆覆盖对小麦产量及农田生态效应的影响

为明确西北地区秸秆覆盖小麦增产机理,在查阅相关研究成果的基础上,分析了秸秆覆盖对小麦产量及其构成要素的影响,发现免耕秸秆覆盖可较无覆盖提高西北地区小麦产量10%～20%,增产效果显著。分析原因,发现其对小麦增产的机理在于对农田生态效应的有效调控:秸秆覆盖可较露地显著增加土壤大团聚体数量,提高土壤结构的稳定性;增加土壤0～200 cm土层含水量;调节地温,避免温度的剧烈波动;增加土壤微生物群落及土壤肥力;提高土壤酶活性。该文主要概述了西北地区秸秆覆盖对小麦产量及农田效应的影响,旨在为西北地区小麦秸秆覆盖提供理论依据。      

Overland water and salt flows in a set of rice paddies

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.     

瓦房店市水果生产标准化发展研究

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。     

金谷子耐旱TG118引种试种及推广应用

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。     

对《种子法》存在问题的探讨

《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。     

Review of the Egyptian experience in implementing land drainage projects

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.     

和谐社会理论建设的几点哲学思考

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。     

A European irrigation map for spatially distributed agricultural modelling

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.     

粉质仪和拉伸仪在面粉生产中的应用

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。     

农村信息化服务的现状及建设措施

分析当前我国农村信息化服务的现状,提出加强农村信息化服务的新举措。     

车辆ABS控制算法的研究及探讨

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。