Plant detection and mapping for agricultural robots using a 3D LIDAR sensor

In this article, we discuss the advantages of MEMS based 3D LIDAR sensors over traditional approaches like vision or stereo vision in the domain of agricultural robotics and compare these kinds of sensors with typical 3D sensors used on mobile robots. Further, we present an application for such sensors. This application deals with the detection and segmentation of plants and ground, which is one important prerequisite to perform localization, mapping and navigation for autonomous agricultural robots. We show the discrimination of ground and plants as well as the mapping of the plants. Experiments conducted using the FX6 LIDAR by Nippon Signal were carried out in the simulation environment Gazebo, with artificial maize plants in the laboratory and on a small maize field. Our results show that the tested plants can be reliably detected and segmented from ground, despite the use of the low resolution FX6 sensor. Further, the plants can be localized with high accuracy.     

Economic Analysis of an Irrigation System for Liquid Manure Application

Irrigation application of effluent from lagoon based systems is an important aspect of animal manure management in swine rearing facilities. This paper describes a procedure for obtaining least-cost components and operational parameters for an irrigation system used to apply liquid manure. The paper employs propositions from hydraulics—affinity laws and Hazen–Williams formula—to derive statistically estimable relationships between pressure, liquid output, power requirement, and impeller speed of an irrigation system. Coefficient estimates are then used in a spreadsheet based decision support system that employs an optimization program to select the least costly irrigation system. A practical application is showcased through simulation of three hypothetical swine farms. Main findings are that the use of this optimization procedure can result in cost savings for swine growers applying manure by irrigation and that the cost savings potentials increase with the farm size.     

流域农业非点源污染研究概况

本文对有关非点源污染的概念作了简要介绍,并从流域内非点源污染物浓度与负荷、影响因素及机理、预测与评价、模型化以及控制与管理等方面,介绍了以流域为单位的农业非点源污染研究概况。     

Can mobile phone-based animated videos induce learning and technology adoption among low-literate farmers? A field experiment in Burkina Faso

ABSTRACT

This article explores an innovative approach to deliver information about new agricultural technology that combines a versatile and potentially lower cost method of developing animated videos with another low-cost method of sharing it on mobile devices (i.e. mobile phone). It describes a randomized controlled field experiment conducted in Burkina Faso to evaluate the effectiveness of animated videos shown on mobile phone compared with the traditional extension method (live demonstration) in inducing learning and adoption of two post-harvest technologies among low-literate farmers. Results suggest that video-based training was as effective as the traditional method in inducing learning and understanding. For technologies that farmers were already aware of animated video shown on the mobile phone was also as effective as live demonstration in inducing adoption. However, in transferring new technologies, the traditional method was more effective in inducing adoption at p?<?.10, but not at p?<?.05. Potential role of mobile phone-based videos as part of the agricultural extension system is discussed.     

云、贵、川地区农业持续发展面临的挑战及对策

本文首先简述了我国云、贵、川三省概况及其存在的资源优势与潜力;其次,分析了三省农业持续发展面临的问题和挑战;最后,提出了云、贵、川三省农业持续发展的战略措施和对策。     

《耕织图》与蚕织文化

《耕织图》从宋代诞生以后,历经元、明、清各代,并以各种载体广泛传播,不仅对中国和东南亚地区的耕织发展具有重要的影响,而且远及欧洲,被誉为“世界第一部农业科普画册”。本文论述《耕织图》诞生后所形成的文化现象,对蚕织科技发展的推进及对国际蚕织文化的影响。     

A study of tile drain nitrate - δ<Superscript>15</Superscript>N values as a tool for assessing nitrate sources in an agricultural region

It is important to evaluate tools which provide insight into nitrate (NO^–₃) contamination source identification in watersheds where multiple nitrogen (N) sources are applied. As nitrate-N stable isotopes have been previously used to identify contaminant sources in groundwater environments, the application of the technique to tile drainage outflow was investigated. Nitrate-N isotopic and concentration analyses of tile drain discharges from six different fields with a range of mineral fertilizer N and hog manure applications were conducted to examine general isotopic patterns and their relation to N fertilizer sources. ¹⁵N of NO^–₃ draining fields were compared to ¹⁵N source signatures through a single growing season. The objective was to determine: (a) whether tile drainage water exiting fields receiving different N sources (inorganic mineral N, organic hog manure N, or a combination of the two) had distinct ¹⁵N values, and (b) whether ¹⁵N signatures of sampled tile drain water fell within expected source ranges. Results suggest that isotopic data differed between fields in a manner consistent with differences in NO-3 sources, as fields only fertilized with mineral N had ¹⁵N values consistently lower than fields with hog manure applications. However, all fields showed isotopic values that were enriched in ¹⁵N relative to their sources during the study period. Therefore, although these fields are discharging tile drainage water with distinctive isotopic signatures, the data suggests that a quantitative evaluation of individual NO^–₃ source contributions is not possible within this watershed. Utilization of this tool in source discrimination in other tile drainage waters should only proceed if it can be demonstrated that isotopic fractionations are not altering source signatures.     

State Policy and the Yeoman Ideal: Agricultural development in Western Australia, 1890-1914

The significance of the 'yeoman ideal' in the formulation of Western Australian agricultural development policy between 1890 and 1914 is examined. It is argued that the colonial and, later, state governments of Western Australia regarded themselves not only as the promoters of economic development, but also as the architects of a desired cultural landscape and social class. This was reflected in numerous government reports, legislation and advertising that emphasized the virtues of smallscale family owned and operated yeoman farms. It is pointed out that, despite the serious ongoing environmental and economic difficulties facing this type of farming, the state remained captivated by the yeoman ideal until at least the onset of the First World War.     

山西省农业旱情产量型评价指标体系软件的开发与编制

文中介绍了山西省农业旱情产量型评价指标体系软件的设计与开发过程，并简要讨论了在这个过程中所遇到的一些问题。     

Ozone for Plant Pathological Applications

The effect of ozone on Xanthomonas oryzae pv. oryzae, a bacterium causing leaf blight disease in Paddy (Oryza sativa), was studied in culture. Viability of this pathogen was lost by flushing ozone at a flow rate of 300 ml/min for 3 minutes in culture condition. The inhibitory effect was dependant on cell concentration and time. With a cell concentration of 0.008 OD at 540 nm, the inhibition of the bacterium was total and no growth was observed in nutrient agar plates even after 36 hrs. With higher concentrations of cells (0.08 OD and above) the bacterium survived, though there was a bacteriostatic effect initially. Conductivity of the cell suspension increased after ozone treatment owing to altered cell membrane permeability and subsequent release of cellular contents. As the bacterium is seed borne, washing the paddy seeds with ozonized water would help control the bacterial blight of rice, the most serious disease of rice in Asia.