北京市大中型沼气工程调研分析与建议

为详细了解北京市大中型沼气工程发展现状,2009年夏季抽选了北京市38座大中型沼气工程进行实地问卷调查,并于2010年冬季再次进行调查。调查内容包括工程投资、工程所有单位、工程设计施工单位、工程工艺、运行管理、沼气和沼液沼渣利用、夏季和冬季运行状态等方面的情况。同时,对调查所获数据进行了分析。调查结果表明:北京市大中型沼气工程以获得能源、服务农村和保护环境目的为主;市政府对工程投资力度较大,工程设计施工体系初具产业规模;工程工艺以能源生态型为主,冬季加热方式主要采用燃煤加温;沼气利用以农户炊事为主,沼液沼渣利用率差。由于沼肥经济效益低,产气量不高,冬季采用燃煤加热和购买原料等原因,工程经济效益不明显。最后,总结了目前北京市大中型沼气工程存在的主要问题,并提出了相关建议。     

解用户之忧，促沼气发展

农村能源建设是农村经济可持续发展和农业现代化的基础工作之一。发展以沼气为纽带的生态型农业，对国民经济和农村经济发展具有十分重要的意义。随着赣州“猪—沼—果”工程、北方“四位一体”工程等生态农业模式的逐渐推广，沼气的综合利用越来越被人们所重视。但长期以...     

农村河道生态治理模式研究

随着社会经济的发展,农村河道侵占严重,水面积锐减,河道淤积导致水利生态功能弱化,河道坍塌导致植被生态弱化,水环境受到很多污染源的影响,特别是农村面源污染。对农村河道的治理应该从水环境治理和河道结构治理两方面着手。河道水环境模式有循环利用生态治理模式、整体优化生态治理模式、多尺度相结合的生态治理模式、多技术集成的生态治理模式。河道结构治理模式包括自然生态型河道治理、工程生态型河道治理以及景观生态河道治理三种治理模式。     

养殖场沼气工程设计和施工监理工作的管理亟待加强

本文通过对我国养殖场沼气工程设计和施工过程中存在问题的分析，阐述了加强养殖场沼气工程设计资质管理和工程监理的必要性，并提出了相应的措施。     

应用沼气技术 建设生态家园—西部农村实施富民计划的技术思路及可行性探讨

从理论与实践的角度，探讨了西部农村实施生态家园富民计划的技术思路及其可行性。提出以沼气技术为纽带，充分发挥“一气”（沼气）带“三料”（燃料、肥料、饲料）、“三料”促“五业”（农、林、牧、副、渔）、“五业”出“效益”（经济、生态、社会效益）的发展思路。     

农村能源建设与农业可持续发展关系的探讨

本文通过以沼气纽带的农村能源生态模式的论述，阐明了农村能源在农业可持续发展中的重要作用。     

发展户用沼气 推动农村小康建设

发展户用沼气，建设生态家园是推动农村小康社会建设的有效途径。介绍了山西省屯留县发展“一池带多改”户用沼气的重要性和取得的成效。     

山区中小型畜禽养殖场沼气工程治污技术北大核心

随着工业化、城镇化如火如荼的推进,山区农村常住人口锐减,散户养殖萎缩,规模化养殖场增加,农村户用沼气使用率逐步下降已成必然趋势。山区规模畜禽养殖场的大量发展,对周边农田和环境势必造成严重污染,而中小型沼气工程＂能源生态型＂（或＂能源环保型＂）工艺,是治理规模化养殖场污染。     

山东省东营市发展沼气生产建设生态家园

近年来东营市市委、市政府把发展沼气生态建设作为实现农村可持续发展和创建文明小康村的一项重要举措来抓,积极引导农民兴建沼气池.先后完成了国家、省组织实施的"四位一体"生态模式建设、"六小工程"中的沼气建设和生态家园富民工程中的"一池三改"沼气建设.全市已累计建设沼气池5080个,年产气130万立方米,折标煤近千吨;建成了"猪-沼-菜"北方生态农业模式200户,生态农业得到了健康发展.     

沼气技术对减少农村畜禽粪便污染的作用

随着近年来我国农村经济的不断发展,农村的生态环境也在不断的恶化.生态破坏、农业生产污染以及食品污染引发的安全问题经过长期积累正逐步暴露出来,已经严重影响我国生态农业的建设和新农村建设的发展.本文通过对畜禽粪便沼气发酵前后的分析、对比,来说明农村户用沼气和大中型沼气工程对畜禽粪便的有效处理,指出发展沼气建设对解决农村大气、土壤、地表水、地下水和人居环境污染严重等问题的现实意义以及对新农村建设、保护农村生态环境的重要作用.     

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。