A vegetation survey has been completed for gathering information and diagnosis of degradated vegetation in Wulanaodu, Western Keerqin Sandland, Inner Mongolia, China. Serious desertification of pastures occurred there after 1950s. On the sandland and sand dunes areas the non-degraded vegetation is Caragana microphylla-Cleistogenes squarrosa, which is a shrub and perennial caespitose grass dominant community. The most degraded vegetation is dominated by such annuals as Setaria viridis and the psammophyte Corispermum telegium and others. On the lowland meadow soil, the non-degraded vegetation consists mostly of perennial grass such as Hemarthria japonica. The lightly degraded vegetation is dominated by Calamagrostis epigeios, and the heavily degraded one by such annuals as Setaria viridis. In the lowland areas with saline-alkali soil, the non-degraded vegetation is dominated by Aneurolepidium chinense, a rhizomatous grass with broad adaptation. Lightly degraded vegetation is dominated by Hordium brevisublatum, while the degraded vegetation is mostly Suaeda corniculata, a halophyte. These results indicate that degraded pastures are dominated by sand loving annuals or halophytes on the saline-alkali lowlands.

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In Japan, it is known that zoo parks have some problems with the control of non-toxic wastewater and increasing feed costs. In this study, a system on the utilization of aquatic plants as a bioremediator and animal feed was investigated at Kumamoto Zoo park. When three aquatic plants (Eichhornia crassipes, Pontederia cordata and Zizania latifolia) were cultivated in a basin supplied with wastewater, concentration of total phosphorus in the water significantly decreased with the growth of plants. The raw materials of harvested plants were eaten with good palatability by wetland animals. In addition, the use of plants as animal feed led to a decrease in feed cost of approximately 80,000 yen per month. Investigation of ensiling to store Pontederia cordata and Zizania latifolia suggested the necessity of additives to improve silage quality. From this study, it was suggested that a system for the bioremediation of non-toxic wastewater by aquatic plants such as Zizania latifolia, Pontederia cordata, Eichhornia crassipes and also the utilization of these plants as feedstuff were useful at zoo parks and in the livestock industry.

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Under the grazing condition, the vegetation on Miscanthus-type grassland changes to Zoysia-type grassland. In relation to vegetational change of Miscanthus-type grassland, changes in the species diversity, H', were calculated. In accordance with grazing, the species diversity raised as the extended summed dominance ratio of Miscanthus sinensis fell. However, after continuous grazing, M. sinensis declined and the species diversity fell as the raise of the extended summed dominance ratio of Zoysia japonica. Under the grazing condition, the species diversity of grassland showed the maximum value when the extended summed dominance ratio of M. sinensis and Z. japonica were about medium value.

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In this study, the Semantic Differential method (SD method) was applied to the evaluation of grassland landscape. Eighty slides of the various grassland landscapes were scored by the seventeen male subjects with the fifty SD scales, and then the Factor Analysis was conducted on the SD scores. Among the fifty SD scales, three scales (attractive/not attractive, comfortable/not comfortable and scenic/not scenic) were included as amenity indicators. Then the relationship between the amenity indicators and the physical features of landscape was examined, according to the Quantitative Theory Type I. The fifty SD scales were classified into fourteen image factors by the Factor Analysis. The amenity indicators were included in the factors of attractiveness and prospect, and the scores of the indicators related significantly to the scores of the other factors such as greenness, strength of impression, openness, ornateness and familiarity. Analysis of the Quantitative Theory Type I showed that amenity of grassland landscape was largely influenced by the eye direction to see the grasslands, the kind of the most distant landscape elements, the landscape element surrounding the grassland, the type, size and color of the grasslands, the existence of appreciative plants, and the kind and color of facilities on the grasslands.

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Estimating the monthly and annual productivity of each grass species according to the climatic conditions is essential to select the optimal grass species for grasslands. Two production models, one using a neural network and the other using a multiple regression analysis, were constructed based on data of monthly dry matter production under various climatic conditions for three grass species. These models were then evaluated for practical use by comparing conformity of estimated data with actual harvest data. Using 165 items of harvest data with three grass species for three years, models were constructed using both methods, and these models were compared for the estimation accuracy each other. The results clearly showed that the neural network had a higher coefficient between estimated data and harvest one. Accordingly, the neural network model showed the better estimation for grass productivity.

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In Japan, recently it has been recognized that pasture have a function as a recreational area. For the pasture management planning taking account recreational use, computer system which can be operated on personal computer is requested by managers. A computer program which enables to simulate landscape change after pasture development and locating of recreational facilities was developed. First of all, the subsystem to display the distribution map which shows visible area of 64,000 mesh (10.6 x 10.6m / mesh) was developed. The visible area map obtained only from the altitude factor was compared with the maps after various factors of the land use were added. As a result, the area which have large visiblity has decreased greatly by adding the factors of the land use. Next, the landscape simulation subsystem to confirm the validity of the evaluation by the visible area map was developed and its application was examined. A simulated landscape by this system was generally corresponding to the actual landscape. The extent of lanscape alteration by the forests or the change of land use was able to be confirmed visually on computer display.

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A system for supporting decision making in the planning of recreational facilities in pasture was constructed by integrating the subsystems with the long-distance view and the walk through images. In this system, the visible long-distance view area from the planning region is displayed at first. Next, some points where the selected distant view and a lot of grassland as the middle-or short-distance view can be seen are extracted. When one point is selected from the extracted points, the visible grassland area and a simulated landscape from this point are displayed, and the validity of the proposed points can be confirmed and be examined. Moreover the walk through image making system was developed by improving the landscape simulator. When the moving route is selected in the display, the dynamic images which show the changes of the landscape are drawn in this system. So the changes in a continuous landscape can be examined continuously, when the route of the passing road along the ranch is decided. It is possible to evaluate the landscape beforehand at the planning of recreational facilities and the passing roads in pasture by using this system.

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When grassland is developed or maintained, it is necessary to plan the arrangement of meadow, pasture and conservation forest according to its topographical conditions and forage production targets. A computer system was developed that allows planners to examine land use and estimate the forage productivity of the object region beforehand. This system consists of two subsystems: a data preparation subsystem and a simulation subsystem with an interactive mode. The data preparation subsystem generates the data of inclination degree, azimuth, mean temperature, solar radiation from scanned contour line maps of the object region and estimates monthly dry matter production of forage, using the subroutines of the neural network. The simulation subsystem outputs a plan of land use and the amount of forage production under the land use. If the inclination conditions allowed to be developed, grass species to be sown and minimum area of a pasture are given. As the basic data necessary for assessment are obtained before pasture development, this system is an effective tool for pasture planners.

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Multiple regression analysis were carried out to investigate variables which predict palatability of 14 varieties of orchardgrass (Dactylis glomerata L.) evaluated with heifers in 15 trials for 4 years. Among 41 available variables, which represent agronomic, fibrous, degradable and physical characters, and mineral elements and other chemical constituents, the best combinations of 2 variables were found out in each growing season. Contribution ratios due to regression (R^2) of the palatability on 2 best variables were approximately between 0.6 to 0.95 in all 15 trials carried out from 1991 to 1994. On the whole seasons, 1) concentration of Ca, 2) concentration of P, and 3) flexibility of leaf and stem were considered to be the best positive predictors for the palatability, respectively. In contrast, 1) three kinds of disease (Rhynchosporium scald, rust and total leaf diseases) and 2) ADF were considered to be the best negative predictors for the palatability, respectively. According to the principal component analysis in summer and autumn, palatable variety Lude exhibit remarkable characteristics on quality among 14 varieties: 1) resistance to Rhynchosporium scald, rust and total leaf diseases ; 2) excellent flexibility ; 3) high concentration of Ca and low ratio of K/(Ca+Mg). Although there are some weak points in Lude, it will be a promising breeding material for the improvement of quality in orchardgrass. The concentration of Ca in varieties was negatively correlated with the degree of total leaf diseases, and the value of degradable fraction by 1% cellulase solution (Db) in varieties was negatively correlated with the degree of rust in some seasons and years, respectively.

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