1961-2019年山东省气候生产潜力时空变化特征

基于1961—2019年山东省21个气象观测站的年平均温度和年降水量资料,利用Miami模型和Thornthwaite纪念模型,计算温度、降水和气候生产潜力,并运用气候倾向率、GIS空间插值和R/S等方法分析其变化趋势。结果表明:温度生产潜力以25.1 g/（m2·10a）的速率递增,降水生产潜力呈递减趋势,递减速率17.71 g/（m2·10a）,气候生产潜力呈递增趋势,递增速率0.742 g/（m2·10a）,多年平均值1 106.0 g/m2;在空间分布上,温度生产潜力和降水生产潜力的分布与年平均温度和年平均降水量的分布基本一致,气候生产潜力由东南向西北递减;温度和降水对气候生产潜力均有正影响,其中降水是主要限制因子。R/S结果表明,未来温度生产潜力有较强的持续上升趋势,降水生产潜力持续减少,气候生产潜力会有持续增大的趋势。      

室内植物表型平台及性状鉴定研究进展和展望

植物表型组学研究正逐渐向综合化、规模化、多尺度和高通量的方向快速发展。本文首先介绍了植物表型研究的最新动向。然后针对室内表型监测平台的特点和各类室内表型针对的表型性状进行了系统介绍，包括产量、品质、胁迫抗性（包括干旱、抗冷热、盐胁迫、重金属和病虫害）等。在此基础上，本文还根据通量、传感器集成度和平台大小等把一些国内外流行的室内植物表型平台进行了分类，并介绍了这些室内表型平台在植物研究中的应用情况。同时，本文还介绍了室内表型数据的管理和解析方法。最后，本文着重讨论了室内表型平台的发展方向，并结合中国植物研究的实际情况对表型组学在中国的发展提出了展望，以期为中国植物表型研究提供指导和建议。     

A timothy-beef production model for Atlantic Canada

A five-part timothy-beef deterministic simulation model was prepared to integrate information on various production processes and hence to improve the basis for management advice given by extension workers.The five parts or sub-models are: the growth of the timothy, harvesting the crop, storing it, converting the timothy and other feeds to beef and, lastly, the feeding of cattle and the disposal of manure. Costs and returns are estimated.The model structure and principal biological relationships are described in some detail. Sample outputs for three different cow-calf-feeder regimes are shown and compared.The uses, limitations and potential of the model are discussed.     

生猪养殖设施工程技术研究现状与发展分析

生猪养殖业是我国畜牧业的支柱产业,随着生猪养殖从分散养殖向规模化养殖的发展,对生猪养殖设施工程技术的需求日渐增加。为了向生猪养殖业发展提供参考与支持,对生猪养殖关键设施工程技术的研究与发展状况进行了总结和分析。重点对猪舍、育仔、饲喂、粪污处理设施工程环节进行研究与发展分析。目前,我国已初步形成了适合国情的生猪养殖设施工程技术体系,但与国外发达国家的生猪养殖设施工程技术还存在一定差距,存在养殖设施工程各环节发展不均衡,养殖工程的机械化、自动化、智能化技术水平较低,关键养殖设施工程技术的基础性研究体系不健全,养殖设施配套性差,养殖机械的适用性和可靠性较低等问题。建立健全的生猪养殖设施工程技术的研究体系,加强养殖、饲料、设施工程、资源环境等方面相互融合与协作、深入与系统的研究,开展适于我国南北方配套应用的生猪养殖设施与设备研发,实现生猪养殖过程的健康/福利化、生态化、自动化及至智慧化,将是我国生猪养殖设施工程技术的发展方向。     

A model for estimating potential market offtake from subsistence herds

A mathematical model is presented of the regional cattle herd within a subsistence pastoral system, in a semi-arid region, where empirical data on herd production are restricted to a few basic properties under average conditions.The model was developed to estimate the potential market offtake for a region in Kwazulu (Republic of South Africa). Currently, this region is overstocked and low production levels are prevalent.The model was used to simulate various offtake strategies and it was found than an approximate threefold increase in sustainable annual revenue can be achieved while simultaneously reducing grazing pressure.     

基于计算机视觉的玉米籽粒形态测量与研究

视觉技术目前被广泛应用于社会各生产领域,包括制造行业、文档分析、医疗诊断及农业品质检测等。为此,基于计算机视觉技术,设计出一种玉米品质自动检测分析方法,即玉米籽粒实时分析系统,具有客观、高效、准确的优势,解决了传统人工检测模式下主观、低效、误差大等问题。最后,设计出一种基于计算机线扫描技术和自动化控制技术相结合的玉米籽粒考种装置。     

Responding to stakeholder's demands for climate information: from research to applications in Florida

Previous research shows that Florida's climate and agricultural production are influenced by the El Niño-Southern Oscillation, suggesting that farmers and ranchers might use new methods of climate forecasting to modify management, increase profits and reduce economic risks. The purposes of this paper are to describe the framework used by a Florida Consortium (FC) of researchers to assess the potential use of climate forecasts in agricultural decision-making and to summarize what was learned in the research process. The framework includes components for generation, communication and use of climate information as well as an implementation and evaluation component. Results showed that winter months are affected most by ENSO phase (higher rainfall and lower temperatures in El Niño years and the opposite during La Niña years). Yields of most crops were significantly associated with ENSO phase as were prices of some commodities. Through various mechanisms of interacting with farmers, ranchers, and extension faculty, we learned that interest in climate forecasts varied widely from highly optimistic to skeptical, and that these clients had good ideas of how to vary management if they have good forecasts. Case studies aimed at understanding potential value and risks associated with use of climate forecasts were conducted for winter fresh market tomato, cow-calf operations, and peanut production. Analytical results, confirmed by interactions with clients, showed significant value in using climate forecasts to alter specific decisions. Risks of using climate information varied among commodities, with considerable risk found in tomato due to the strong link between production and price. Perhaps the most important lesson learned was the importance of engaging trusted advisors in research and outreach efforts. A major output of the project was the close cooperation established between the FC and the Florida Cooperative Extension Service. Prospects for sustaining a climate information program in Florida are high due to joint research and extension initiatives.     

A review of bio-economic simulation models of beef production systems and suggestions for methodological development

This paper sets out to review eight beef production simulation models constructed over the past decade. All eight models are identified as belonging to a class of bioeconomic model referring to beef grazing systems at the level of the farm firm.Aspects given consideration in the review include model objectives, the handling of biological and economic components of beef production systems, risk and management variables and the uses to which the various models have been put.Various aspects of the development and use of such models are discussed, including alternative future courses for methodological development.     

Evaluation of new technology on farms: Methodology and some results from two crop programmes at CIAT

The yield gap between experiment station and farm yields in the production of food crops in developing countries has been frequently noted and various quantitative attempts have been made to separate its components in irrigated rice (Gomez et al., 1979; IRRI, 1979; Flinn, 1980). In two food crops in Latin America one principal hypothesis of the authors for the continuation of this yield gap over time is that many successful technologies on the experiment station do not pass a set of reasonable farm level criteria. Farm testing is the logical extension of the research evaluation process once a technology has been identified on the experiment station and regionally tested for adaptation. Farm testing is an especially important component of the research process in developing countries, where communication links between farmers and researchers are weak and farmers often do not have the information or management experience to combine and modify various technology components adapting experiment station or regional trial observations to their owen environments and production systems. The research problems at the farm are different from those at the experiment station or in regional trials so there are important distinctions in design and analysis in the farm trials. The evaluation process developed here identified the technologies later adopted by farmers. For the unsuccessful technologies, information was provided from the farm trials to the breeders and other scientists on further design requirements. The results of the farm trials substantially modifie the recombinations for farmers, which would have been arrived at utilising the results from the experiment station and/or regional trials.     

Tailoring agricultural extension to different production contexts: a user-friendly farm-household model to improve decision-making for participatory research

Farmers operate within specific natural and socio-economic settings. When those settings are very diverse, as in mountainous areas, agricultural extension services have often failed to tailor interventions to the specific needs of client farmers. In such settings, extensionists need cost-efficient tools or a close link to researchers to evaluate potential strategies and activities to raise farmers' income. This need has become more critical as governments in developing countries downsize expenditure on extension services and donors demand impact from their investments. This paper outlines a flexible computer-based farm-household model designed to assist researchers, extension workers, and policy makers. The model allows the user to define specific production options and resource constraints under different socio-economic and biophysical settings. Model application in different regions has proven its flexibility to capture and analyze a variety of production systems. When used with site-related input data and effective dialogue on the results among researchers, extensionists, and farmers, the model can be a useful tool for participatory research and extension.     

Modelling the impact of interventions on the dynamics in village poultry systems

There are many technical possibilities to improve free-range and backyard poultry keeping. Rural households, however, are not adopting these technologies widely. This paper presents a model approach for ex ante evaluation of interventions in village poultry systems. The dynamic deterministic computer model considers mortality, egg production, reproduction, offtake, and their interrelationships. In the base situation, the model reflects the behaviour of a relatively stable village poultry flock. The model was used to explore how interventions influence the dynamics of a village poultry flock. Over the simulated period of three years, NCD (Newcastle Disease) vaccination, daytime housing, supplementary feeding, and control of broodiness each had a positive effect on bird offtake, egg production, egg offtake, and flock size. Crossbreeding had a highly negative effect on these key variables. The impact of interventions is also related to the use of the available resources. Cost–benefit calculations for the Tigray region in Ethiopia and village poultry research sites in Kenya indicated that NCD vaccinations were economically most effective. Housing and crossbreeding had a highly negative impact on net returns. When applied with situation-specific input data, the model can be used in the first stages of research and development approaches to support decisions on priorities of projects in village poultry production.     

铧式犁犁体曲面研究现状与展望

犁耕作业是一种应用最为广泛的耕地方式,良好的犁体曲面不仅能使土壤达到理想的农艺作业要求,而且可以降低犁耕作业过程中的能量消耗,通过对犁体曲面的几何特征、性能参数、耕作过程和设计方法等方面进行阐述分析,总结基于犁耕作业过程中的土垡运动及受力的各类研究方法,分别从经验设计、几何形成线法、土迹线模拟法、基于犁耕工艺过程的犁体...     

基于植被指数的锡林河流域生物量动态遥感估算

本研究以地面样方调查结合2000-2013年MODIS—NDVI数据,建立样方生物量和遥感数据的关系模型,反演锡林河流域产草量的时空分布。研究结果表明：建立的植被指数模型相关系数达到0.6以上,模型精度为80%,线性模型作为遥感估测应用可行;锡林河流域年平均产草量鲜重为1001kg/hm2,空间分布呈现东南高-西北低的空间分布规律;2000-2013年,产草量年际间变化大,变异系数为51.6%,产草量总体呈波动上升趋势。锡林河流域草原产草量的时空变化与主要气候因素（气温、降水）关系密切,特别是受降水量的时空变化影响更为显著。本研究结论可以为有效地保护和利用草地资源、合理配置载畜量和恢复草原生态环境提供有效的技术支持和保障。     

Simulation modelling for orchard management

A simulation model is presented for a typical Australian pome fruit orchard. The main routine calculates annual after-tax profit and sub routines generate optimum replacement age and stochastic variability due to hail and drought. The principal dependent variables such as prices, yields and costs can be changed as required to add flexibility for various practical circumtances. Two replacement policies are used, self replacement (270 trees/ha) and semi-intensive (715 trees/ha). Under mean price and yield conditions, converting the orchard to semi-intensive production gives an average annual improvement in profit of $13 000 over a 100 year simulation period. Results emphasised the need for earlier replacement of trees than is usual practice. Existing trees were replaced at 31 years of age and thereafter recycled at 46 year intervals. Application of regression analysis to produce iso-performance curves revealed important interactions between price, cost, yield and orchard profitability with price being the most sensitive parameter.     

DVE闭环系统中驾驶人模型分析与研究

对DVE(Driver,Vehicle and Environment)闭环系统中典型驾驶人模型进行分类分析,在总结现有模型的基础上,提出了一种基于驾驶视角的驾驶人行为模型,运用MATLAB/Simulink工程软件,建立DVE闭环系统仿真模型。仿真和试验结果证明:所建模型充分考虑了驾驶人前视效应,道路跟随效果较好,符合驾驶人实际驾驶特征。该模型可为以后驾驶行为特征相关研究提供新的参考。     

Simulated long-term nitrogen losses for a midwestern agricultural watershed in the United States

Adequate knowledge on the movement of nutrients under various agricultural practices is essential for developing remedial measures to reduce nonpoint source pollution. Mathematical models, after extensive calibration and validation, are useful to derive such knowledge and to identify site-specific alternative agricultural management practices. A spatial-process model that uses GIS and ADAPT, a field scale daily time-step continuous water table management model, was calibrated and validated for flow and nitrate-N discharges from a 365 ha agricultural watershed in central Iowa, in the Midwestern United States. This watershed was monitored for nitrate-N losses from 1991 to 1997. Spatial patterns in crops, topography, fertilizer applications and climate were used as input to drive the model. The first half of the monitored data was used for calibration and the other half was used in validation of the model. For the calibration period, the observed and predicted flow and nitrate-N discharges were in excellent agreement with r² values of 0.88 and 0.74, respectively. During the validation period, the observed and predicted flow and nitrate-N discharges were in good agreement with r² values of 0.71 and 0.50, respectively. For all 6 years of data, the observed annual nitrate-N losses of 26 kg ha⁻¹ for the entire simulation were in excellent agreement with predicted nitrate-N losses of 24.2 kg ha⁻¹. The calibrated model was used to investigate the long-term impacts of nitrate-N losses to changes in the rate and timing of fertilizer application. Results indicate that nitrate-N losses were sensitive to rate and timing of fertilizer application. Modeled annual nitrate-N losses showed a 17% reduction in nitrate-N losses by reducing the fertilizer application rate by 20% and switching the application timing from fall to spring. Further reductions in nitrate-N losses require conversion of row cropland to pasture and/or replacement of continuous corn or corn–soybean rotation systems with alternative crops.     

母猪智能群养系统在生产中的应用研究进展

随着近几年来电子智能化和农业机械化的高速发展,以及养猪行业人工成本、饲料、药物成本等的增加,急需需找降低养猪成本的养猪模式是养猪行业的一个紧迫任务,母猪智能群养系统具有降低人工成本、减少饲料浪费、提高母猪生产性能等提高经济效益的优点,智能机械化是养猪行业未来发展的趋势之一,文章在国内内外研究的基础之上,就母猪智能群养系统在生产中的应用研究进展进行了综述。     

Computer simulation of monitoring herd productivity under extensive conditions: Sampling error of herd size and offtake rate

Monitoring extensive pastorialist herds was simulated using a personal computer program designed to yield balance sheets for numbers and annual rates of births, mortalities, cullings and herd growth, as well as for herd structure in successive periods of weeks or months. Instead of calving rate, the program used frequency distributions of first parturition age and parturition interval, together with sterility rates, to generate individual reproduction. It took 15 years for herd size to become free from carry-over effects due to inherent herd history. Offtake rate seemed to be a convenient statistic for measuring productivity under the conditions of stable environment and herd policy. It was not auto-correlated and its sampling error followed binomial expectation. The standard error of annual offtake rate was large and, even with monitoring periods of as much as two years, some herds were three or four times as productive as others. A menu-driven program that can handle different animal species and various herd development policies without prior modification can be useful for testing hypotheses which would otherwise be difficult to treat mathematically. Practical monitoring schemes should maintain corresponding packages for routine purposes.