动态

●北京市农业生态环境质量普查工作全面启动北京市农业环境监测站目前已全面启动了农业生态环境质量普查工作,此项工作旨在摸清首都农业生态环境质量的“底数”,为形成基于“3S”技术的农业生态环境质量监测提供基础数据。此项工作作为北京市新农村建设的一项基础性工作和安全农产品质量保障工作的重要内容,将为无公害农产品产地分级、认定和产品认证打下坚实的基础,也为首都郊区农业结构调整和土地利用规划提供可靠的依据,从而实现农业资源与环境合理有序开发和利用,促进农业经济的协调、可持续发展。(北京市农业环境监测站张敬锁黄生斌)…     

拜泉县农业生态在生态经济规律的指导下前进

拜泉县近半个世纪来，前期农业的发展从兴旺走向衰退。近八年来推行“生态农业”基本模式，农业又走向了兴旺，井显示出愈来愈大的活力。这一成就是在生态经济规律的指导下取得的，其核心是使经济与生态协调发展。他们的主要做法是：１．大力种树种草，２．组织生态系统“食物链”，３．重建农业生产结构。现在拜泉县已建成“生态农业县”，并正向“生态经济县”的新阶段前进。     

“闭路开环”原理在西部生态经济建设中的应用

阐述了“闭路开环”原理内涵及其基本内容,分析了“闭路开环”原理在西部生态经济建设中的政策含义(包括投入政策、激励约束政策和人才政策)与实践意义,并针对西部生态经济建设模式、生态产业、园区生态经济和生态经济制度建设等提出具体策略     

黄土高原沟壑区王东沟流域农业生态经济系统演变过程

[目的]探讨黄土高塬沟壑区王东沟流域1986—2013年间农业生态经济系统演变过程,分析不同演变阶段农业生态系统和农业经济系统间的耦合态势,为该地区经济社会可持续发展提供参考。[方法]基于黄土高塬沟壑区王东沟流域长期监测数据和农户调查资料,建立了农业生态经济系统综合评价指标体系,应用耦合度模型对农业生态经济系统演变过程中的耦合态势进行了分析。[结果](1)黄土高塬沟壑区王东沟流域1986—2013年间农业生态系统和农业经济系统综合指数呈上升波动趋势。(2)农业生态经济系统演变过程中农业生态系统和农业经济系统耦合态势经历了恢复发展阶段、协调发展阶段、恢复发展阶段,目前处于协调发展阶段。[结论]在农业生态经济系统演变过程中,通过农业资源合理调配,促使农业经济获得新的增长点,农业生态经济系统能够高效稳定发展。     

何谓农业生态经济

农业生态经济(agriculturaJ ecological economics):农业再生产中生态与经济的内在联系及相互结合的统称。农业生产首先是自然再生产。又通过人类有目的的农业技术操作和各种农事活动,把活劳动和物化劳动输入农业生态系统,并通过经济技术的主导作用,使生态与经济结合,促     

中国科学院长武农业生态试验站简介

中国科学院长武农业生态试验站简称“长武生态站”,属于“中国生态系统研究网络”(CERN)设在黄土高原沟壑区的一个基本站。依托于中国科学院、水利部西北水土保持研究所。长武生态站位于陕西省长武县洪家乡(312国道西兰线201km,与甘肃省泾川县毗邻)。生态站中心任务是研究     

中原城市群“三生”用地转型及其生态环境效应

[目的]分析2000—2020年中原城市群“三生”用地的时空演变特征及其生态环境效应，为快速城镇化地区“三生”空间格局优化以及区域生态环境保护等提供科学参考。[方法]基于中原城市群2000,2010和2020年3期土地利用数据，采用生态环境质量指数和景观格局指数两种方法，定量分析中原城市群“三生”用地转型的生态环境效应。[结果](1)研究区生产用地面积明显减少(-7 890 km~2),生态用地面积相对稳定(仅变化0.1%),生活用地面积快速增加(7 638 km~2);2000—2010年的“三生”用地转换面积远低于2010—2020年。(2)研究区生态环境质量指数先升后降，在区域整体上呈现“西高东低”的空间格局。郑州市下降幅度最大，济源市提高最多；生态环境质量指数(EV)与最大斑块指数(LPI)、景观形状指数(LSI)、斑块结合度指数(COHESION)、聚集度指数(AI)、香农多样性指数(SHDI)和香农均匀性指数(SHEI)高度相关。(3)生态环境改善趋势小于恶化趋势，恶化的主要因素为林草生态用地向农业生产用地转化，以及生活用地对农业生产用地的占用。(4)各类景观破碎化加剧，聚...     

长江流域水土流失生态化治理模式探讨

长江流域中上游的水土流失十分严重,已严重威胁到全流域的社会、生态、经济的可持续发展。虽然“长治”、“天保”、“退耕”三大工程的实施在一定程度上遏制了水土流失的加剧,但其本身仍有许多局限与不足。由于治理长江流域水土流失十分重要和紧迫,本文在详细分析的基础上提出了开征生态税、发展生态经济农业、实施生态移民、加大生态进口和发展生态旅游等一系列长江流域水土流失生态化治理的新模式。     

基于DPSIR模型的渭河干流甘肃段生态安全评价

[目的]分析渭河干流甘肃段生态安全现状,为该流域生态文明建设提供理论依据。[方法]通过DPSIR模型构建渭河干流甘肃段生态安全评价指标体系,运用组合赋权法确定指标权重,并利用障碍模型诊断障碍因子。[结果](1)渭河干流甘肃段生态安全指数呈先降后升的趋势,生态安全等级由Ⅳ(较危险)经Ⅴ(危险)先向Ⅳ(较危险)再向Ⅲ(预警)转变;(2)项目层指数变化幅度较小,驱动力、压力和影响指数波动下降,状态和响应指数波动上升,生态安全状况整体有所好转;(3)人口增长率、经济增长率、植被覆盖率、城镇污水处理率和农业用水利用率是影响渭河干流甘肃段生态安全的主要障碍因子。[结论]未来应注重经济、政治、文化、生态环境四者的有机统一,进一步推动经济与生态的和谐发展。     

河南省农业生态资源保护与农来可持续发展

分析了河南省农业面临的水土资源、森林与草地资源及生物多样性等问题,指出实施”科教兴豫“战略,控制人口增长,合理利用土地和水资源,保护生态环境,逐步建立起结构和功能不断优化的农业生态经济复合系统,是实现河南省农业生态经济良性徨和可持续发展的有效途径。     

广西来宾县干旱系统分析及生态治旱对策

来宾是广西最旱的县，干旱频繁，严重影响农业生产和农村经济的发展。本文系统分析了该县干旱的原因，认为自然条件和人类活动的影响是干旱致灾的原因。针对农业生态经济系统存在的问题，提出了关于调整系统结构、增强系统功能的生态治旱对策。     

酶标仪在稻米表观直链淀粉含量测定及突变体筛选中的应用

探索了 96孔全自动酶标仪 (SpectraMax 1 90 ,Sunnyvale,USA)在稻米表观直链淀粉含量(AAC)测定中的应用效果。实验以IR2 4、Iri371、Z41 3、KMD1、秀水 1 1共 5个品种为材料 ,以农业部部颁标准为参照 ,样本处理后不作定容稀释而直接在 96孔酶标板上进行显色 ,测定OD值 ,根据标样获得的回归等式计算待测样本的AAC。结果表明 ,酶标法与国标法测得的精度无显著差异。利用这一体系 ,对 1 5 0 0余份协青早B的M3 (收自M2 单株 )种子进行了AAC突变体筛选及后代跟踪研究 ,获得了 1份中等AAC( 1 6%左右 )突变体ZXY1 6。该方法操作简便易行 ,据此可建立高通量稻米AAC测定体系     

Three‐dimensional scanning for measurement of bulk density in gravelly soils

The measurement of bulk density in gravelly soils (>15% soil particles >2 mm) is more time‐consuming than for other soils. The excavation method, usually employed for measurement of bulk density in gravelly soils, includes excavating a void and calculating volume of the void from the weight and density of the material (e.g. sand and plaster cast) used to fill the void. A 3‐dimensional (3D) scanning system was developed to measure the volume of the void created when using the excavation method. The 3D scanning system combined a time‐of‐flight camera (Kinect ™), the KinectFusion algorithm, MeshLab and a portable computer to produce a 3D model of the void or plaster cast. Experiments were completed at three field sites where soil gravel (>2 mm) content ranged from 35 to 71% to assess the performance of the system. The void volume measured using the 3D scanning system was highly correlated with measurements using the plaster cast method (r  = 0.99). The cumulative time taken to measure soil bulk density using 3D scanning was significantly (P  <  0.001) less than for the sand replacement at 0–10, 10–20, 20–30 and 30–40 cm depth. The faster measurement of subsurface bulk density is a significant advantage of the 3D scanning system; the time taken to measure bulk density to 40 cm in 10 cm increments using the 3D scanning system was about one‐third of the sand method.     

Development of a radioimmunoassay procedure for aflatoxin B1 measurement

A radioimmunoassaay (RIA) procedure to measure aflatoxin B(1) (AfB(1)) in agricultural commodities was developed. AfB(1) oxime derivative was synthesized, characterized, and used for preparation of (125)I-labeled AfB(1). Antiaflatoxin B(1) serum was raised in-house using AfB(1)-bovine serum albumin conjugate as immunogen. The assay system was optimized in the range of 0.2-5 ng/mL, using a liquid phase (PEG) as well as a solid phase (coated polystyrene beads) separation system. Inter-assay and intra-assay variations, recovery, and parallelism studies validated the assay. AfB(1) analysis was carried out in nearly 130 samples of different agricultural commodities. The correlation coefficient was determined using commercial ELISA and in-house-developed RIA methods.     

中国烟草种质资源网络信息系统的开发

为促进中国烟草种质资源的共享与应用,研究开发了基于B/S（browser/server）架构和ASP.NET技术的中国烟草种质资源网络信息系统。数据库采用了Microsoft SQL Server,服务器端程序集应用C#语言开发,浏览器端基于XHTML + JavaScript。系统在特性数据库和共性数据库两个底层数据库的基础上,实现了种质数据查询、核心种质查询、种质图像查询、共性数据查询和烟草种质共享等5种功能。该系统突破了长期以来种质资源信息、数据、实物集中于一处,难以共享的局面,促进了种质资源的广泛应用和深入发展。     

基于Kalman过滤器的实时拖拉机位置确定系统

该文提出了一个实时拖拉机位置确定系统,该系统由一个六轴惯性测量单元(IMU)和一个Garmin全球定位系统(GPS)组成。在系统中,设计了一个Kalman过滤器来综合两个传感器的信号,以滤去GPS信号中的噪音,融合冗余信息,最后得到一个有较高更新速度的输出信号。此外该系统还能够补偿IMU的偏移误差。通过使用该系统,低价的GPS可以替代高价的GPS,并且保持良好的精确性。试验和融合结果表明该系统确定的拖拉机位置误差比单一使用GPS的系统的误差要大大减小:当拖拉机速度约为1.34m/s时,该系统东向轴的平均偏差为0.48m,而GPS的平均偏差为1.28m;北向轴的偏差从1.48m降为0.32m。系统的更新频率则从原有GPS的1Hz增加到9Hz     

A resuscitation/selection system for rapid determination of Salmonella in foods

A resuscitation medium was developed consisting of a trypticase soy broth base supplemented with 0.5% yeast extract, 0.25% sodium pyruvate, 0.01% sodium thioglycollate, and 0.1% chicken fat. After a resuscitation period of 4 h, the medium was made selective by addition of either sodium thiosulfate, bile salts and iodine, or sodium selenite and L-cystine. The now selective medium was incubated for 16 h. The presence or absence of Salmonella was determined by the Salmonella-Tek antibody-based detection kit. The present system was compared with a method of the Bacteriological Analytical Manual (BAM) for naturally contaminated foods. Nineteen egg products were screened; 3/19 were positive using the BAM method, 9/19 were positive using the present system. Seventeen chicken samples were assayed; 10/17 were positive using the BAM method; 13/17 were positive using the present system. Of 8 pepper samples, 4/8 were positive using the BAM method; 6/8 were positive using the present system. Of 8 spice samples, 6/8 were positive using the BAM method, 7/8 were positive using the present system. Of 6 onion products sampled, 5/6 were positive using the BAM method; 6/6 were positive using the present system.     

A risk analysis methodology for assessing natural resources degradation

Risk analysis has been employed, amongst other things, both to estimate the probability of future water demand emergencies in reservoir systems (using simulation modelling), and to estimate environmental and public health risks (using empirical data). We assert that this framework, when coupled with simulation modelling, can be applied to examine and compare the impacts of resource exploitation, land use and production strategies which may cause land degradation. Our representation of risk analysis relies on the assumption that each land use strategy is associated with a risk of the system (i.e., social system, production system, ecosystem) attaining a subjectively unacceptable environmental condition (e.g. poor human nutrition, crop failure, degradation of a natural resource) sometime during a management planning period. The research methodology entails: (1) the identification of critical variables in the social and biological environment that are affected by exploitation and management of resources; (2) the identification through interviews, surveys, and research of regions of unacceptability in these variables that determine the dynamics of local environmental degradation; (3) the translation of resource policy and practice into a computer model of impact on the resource system; (4) many iterations of simulation of the system to determine the ‘risk of failing’ in each of the critical variables. The presentation of risk probabilities to decision-makers represents a reduction of many simulations into an understandable estimate of environmental impact. More importantly, risk analysis is potentially a learning tool for human system studies, and an interface for applied social science and ecological research.     

Identification of Escherichia coli from shellfish and related environments by automicrobic system

A total of 463 fecal coliform positive isolates obtained from shellfish and related samples gave typical Escherichia coli IMViC reactions. E. coli identifications for 458 (99%) of these isolates were confirmed using a combination of the Automicrobic System (AMS) and the API 20E system (reference system). The AMS (test system) identified 433 isolates as E. coli; the remaining 25 (5%) isolates were identified as E. hermanii by the test system and as E. coli by the reference system. Additional tests performed on the isolates identified as E. hermanii confirmed those AMS identifications to be incorrect.     

Estimation of Free Glycolipids in Wheat Flour by HPLC

The chloroform-acetone mixture (4:1, v/v) was an effective solvent for eluting the nonpolar lipid fraction, including free fatty acids, from the polar lipid (glycolipid and phospholipid) fractions from free lipids of 21 hard winter wheat flours using a solid-phase extraction system. Amounts of monogalactosyldiglycerides (MGDG) and digalactosyldiglycerides (DGDG) in the glycolipid fraction were determined by normal-phase HPLC with a gradient system using an evaporative light-scattering detector (ELSD) and a diode array detectors (DAD). Unsaturated fatty acids showed higher UV absorbances from 200 to 213 nm when compared with saturated palmitic acid. However, significant linear correlation coefficients were obtained between the peak areas measured by a DAD and GL contents determined by an ELSD, suggesting that fatty acid composition of flour GL could be fairly constant. Using an ELSD as a reference, equations for determination of MGDG or DGDG quantities were derived from the peak areas of a DAD by multivariate regression methods. Determination of MGDG and DGDG quantities was also possible using only a DAD.