Precision agriculture (PA) holds promise in achieving uniform crop growth. However, it tends to focus on site-specific fertilizer application based on the non-uniformity of surface chemical properties. It does not consider the influence of soil physical properties on crop growth. This research aims to clarify the relationship between soil physical properties and the moisture content of wheat grain in Memuro Town, Tokachi District, using large-scale soil maps, elevation, the order of wheat harvest and field surveys.
It was found that the harvest is delayed in high elevation areas and areas of mainly Wet Andosols.
To understand which factors influence the moisture content of wheat grain, multiple regression analysis by the stepwise method was conducted. Response variables were elevation, sowing date and soil physical properties. The moisture content of wheat grain was found to be explained 70% by elevation and minimum gravitational water porosity in the effective layer. A regression equation indicated that the lower the minimum gravitational water porosity in the effective layer, the higher the moisture content of the wheat grain.
Wet Andosols are characterized by low gravitational water porosity. A large-scale soil map indicates that soil distribution in the areas of mainly Wet Andosols is non-uniform within a field.
Therefore, if PA is introduced to the studied area, it will be necessary to practice site-specific soil modification of Wet Andosols based on large-scale soil maps.

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The authors implemented a field monitoring system on the Loess Plateau (Yulin College, Shaanxi, China) and provided data through IPv6 after authentication by GRID.
It is difficult to obtain fixed IPv4 addresses, which are not private but global, in developing region such as the Loess Plateau, China. The authors therefore used 6to4 technology with a VPN (Virtual Private Network) to make the IPv6 protocol available on IPv4 networks from the Loess Plateau to Beijing (Institute of Microbiology, Chinese Academy of Sciences), and provided the observed data to the world. The data were transferred after authentication by a GRID computing middleware, Globus. The authors were able to securely provide the observed data to Osaka University, whose security policy does not allow the use of private addresses.
It is, therefore, not necessary for users to manage IPv4-specific functions such as NAT (Network Address Transfer), private addresses, DHCP (Dynamic Host Configuration Protocol). Instead, they can simply connect to an IPv6 network and then receive data. In the future, field monitoring covering a number of developing regions are expected to provide observation data to developed regions, which would be a realization of global ubiquitous computing.

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Topographic data obtained by airplane-based surveys is spatially disordered. There are both high and low density portions in the topographic data, and some data are redundant. A graphical terrain model or a digital elevation model (DEM) is generally generated from raster data, and the decimation (reducing the level of redundancy in data) is based on that data structure. However, this approach is not useful when rasterizing topographic data derived from laser range finders because imposing a raster data structure introduces visual and numerical errors. In this research, topographic data was obtained using a one-axis laser range finder mounted on an unmanned helicopter. The collected data were not evenly spaced over a regular grid as rasterized data are. This paper describes methods that can automatically generate triangular mesh from a topographic data set, and simplify the data while maintaining accuracy. These methods were evaluated by examining the topographical feature error resulting from simplifying the 507 raw data points obtained by the helicopter-based survey. When a data set of 107 points were generated (79% size of the original raw data), topographical error was less than 0.12 m. By way of comparison, when 400 data points were eliminated at random, the corresponding error was 1.35 m. Furthermore, when 110 points data were generated by rasterizing, the error was 0.88 m. Consequently, it was concluded that the developed method was very effective.

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This paper proposes a method of judging whether pesticide use is propriety, and the effectiveness of this method is clarified through development of a pesticide use navigation system (Nouyaku-navi) judgment server and an operational test of that system. The term "Navigation system" is used because the system is intended to guide users through the choices involved in creating a pesticide use plan, much like a vehicle navigation system aids in route selection. Development of the Nouyaku-navi judgment server clarified the main functions that would be required if the system was to be practically used in the future. They are (1) the ability to judge the propriety of a pesticide use plan that includes pesticide product names (rather than pesticides registration number), (2) the ability to process electronic spray calendars of various styles, (3) a clear display of the consequences of a judgement for business. Development of the Nouyaku-navi judgement server highlighted the necessity of having a pesticide use planning support system. The server clarified that a pesticide misapplication prevention support function was required, and that completely automated judgment should not be the aim in system development. Rather, the system should support the gathering of a pesticide user's data and support their decision making.

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In the present circumstances, growers of Gentiana sp., which is the representative flowering plant cultivated at Iwate prefecture in Japan, usually judge harvest stage with their own eyes subjectively. This way of judging often results in misjudgments and destabilizes the quality of shipped flowers. So, in this study, we examined the availability of image-based information to provide objective indices for proper judgement of the growth stage of Gentiana sp. for flower harvest.
First of all, we defined 2 groups of image-based information. The first group contains 4 kinds of information based on the area of petals and buds in an image, and the second group contains 4 kinds of information based on number of buds in an image.
Next, we took a total of 58 photos of Gentiana in the field and calculated the proposed information from these photos. Then, we checked relationship between the proposed information and growth stages as evaluated by an expert in growth stage judgment.
The 6 kinds of information showed considerable correlation with the growth stages as evaluated by the expert.
To more precisely estimate the growth stage, we tried to combine information from the proposed information using multiple linear regression analysis. The correlation coefficient between the combined information and the growth stages evaluated by the expert was beyond 0.9 in 2 verifications.
Thus, it seems that the proposed information has possibility to stabilize the quality of shipped flowers by providing objective indices for the proper judgement of growth stage of Gentiana sp., and therefore has capability to contribute to automation of Gentiana sp. flower harvest in the future.

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Land utilization in Less Favored Areas (LFAs) is facing a turning point. Farm economy and rural communities are facing hardships because of frequent crop damage from wild animals. Besides, farmers are becoming old, making it difficult to continue labor-intensive farming. On the other hand, several cattle farmers are starting to feed their cattle by means of grazing on less utilized arable fields. Grazing is also used in the hope of conservation of rural resources as well as development of extensive and ecological farming in LFAs.
In this report, we have presented the results of a research on the effectiveness of fruit cultivation adopting grazing and its technical issues based on a case study of chestnut cultivation in the Chugoku hilly and mountainous areas. The report clarified the following points.
Firstly, difficulties in weeding on steep slopes during summer and crop damage from wild boars, monkeys, and bears make it difficult for elderly farmers to continue their chestnut cultivation.
Secondly, the adoption of cattle grazing in chestnut fields reduced the previous working hours by two-thirds, and has succeeded in keeping the wild animals in check. However, grazing in the fields has created several issues, such as protecting young trees from grazing cattle and grass management.
Thirdly, integration of chestnut cultivation with cattle breeding increased income, labor productivity, and land revenue under winter breeding. It greatly contributed to the continuation of fruit cultivation and conservation of rural resources carried out by elderly farmers in the Chugoku hilly and mountainous areas.
Finally, to establish and develop fruit cultivation adopting grazing, it is necessary to apply information technology to monitor cattle and weather to improve breeding and reduce pesticide in the orchards.

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