A simple device was developed to automatically sample feces at certain time intervals, and the fluctuations with time in the amount of feces in 4 goats was analyzed using maximum entropy spectral analysis. The fluctuation with time in the amount of feces over time was larger for sorghum silage feeding than maize silage feeding. An obvious peak of spectral density at the frequency of 0.0848 (11.8h per cycle) was detected in the power spectral diagram for sorghum silage feeding. Furthermore, 2 peaks with a lower power density were also detected at lower frequencies of 0.0121 (82.6 h per cycle) and 0.0485 (20.6 h per cycle). In maize silage feeding, on the other hand, a maj or peak was detected at the frequency of 0.0364 (27.5 h per cycle), and lower peaks at 0.0121 and 0.0667 (15.0 h per cycle). Periodic fluctuations such as a daily circadian rhythm, a short-term fluctuation like a semidian rhythm and a long-term fluctuation with a frequency of 0.0121 (82.6h per cycle) were observed in both kinds of silage feeding.

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Carex albata Boott invade and dominate some permanent sown pastures in Japan. To elucidate the germination strategy of C. albata, we tried various treatments for breaking the dormancy of C. albata seeds and investigated the effects of light and alternating temperature on germination of C. albata compared with some species in grassland habitats. C. albata seeds showed dormancy. To break the dormancy, heat treatments, scarification and chilling were attempted, but the dormancy was remained except chilling for six months. Light, alternating temperature and the interactions affected dormancy breaking of the after-ripened seeds by chilling, especially light effect was great. These three effects were also found in the dormancy breaking of C. doUchostachya var. glaberrima, Anthoxanthum odratum and Rumex obtusifolius seeds. These species, however, did not need chilling in order to after-ripen, and alternating temperature effect was great. Moreover, many seeds of A. odratum and R. obtusifolius were released from dormancy under alternating temperature regime (25℃/15℃) in darkness or under constant temperature regime (25℃) in light, although under these conditions, few seeds of C. albata broke dormancy. Since the dormancy breaking mechanism of C. albata seeds was rigid compared with those of other species tested, we considered that the mechanism of C. albata seeds acted as gap detection mechanism in field and became one of the reasons that enhanced dominance of C. albata under permanent sown pastures on which domestic animals or tractors frequently formed bare land.

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We studied the stands of Aneurolepidium chinense, Stipa grandis and Stipa krylovii in the typical steppe and Stipa klemenzii in the desert grassland. The grasslands distributed according to amount of precipitation of this region. In the grazed grassland, the rank of constituent species changed according to varying grazing pressure. In the intensively grazed stand, A. chinense decreased its importance value, and Artemisia frigida raised that value. The species diversity index (H') exhibited the maximum value in the intermediately grazed stand for each community. Moderate grazing pressure prepared a greater number of niches in the plant community for constituent species than that of severe and light grazed stands. The coefficient of variation (C.V.) in phytomass of the stand closely correlated to the species diversity in the typical steppe, while in desert grassland, the C.V. decreased with increasing stand diversity. In the latter stand, local resources for plant growth affects directly to growth and in the former stand, environmental factors work through interaction of constituent species.

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Following the study in the previous paper^4) of the change of vegetation and soil on the process of recovery of the desertified grasslands at the sand dune (site No. 1) and the fiat sandland (site No. 2) in Keerqin Sandland, Inner Mongolia, China, the same study has been carried out at two sites of non-saline meadow (No. 3) and saline meadow (No. 4). The following results were obtained. The meadow which is harvested plants for hay in autumn and grazed in winter is more conservative land utilization than the pasture which is grazed yearlong. Vegetation and soil of three grasslands (A, B and C) which have different backgrounds of land utilization were compared at site No 3. Plot A has been the pasture land for 30 years, B plot had been the pasture land for 20 years and after then it has been the meadow land for 8 years, C plot has been the meadow land for 30 years. Coverage of vegetation (%) was C plot>B plot>A plot. B plot had a higher coverage of species which indicate non-degradation but had a lower coverage of species which indicate degradation than A plot. Thus, vegetation condition of A, B and C plot were poor, fair and excellent, respectively. The soil organic matter and available nitrogen were C plot )B plot≧A plot. Soil pH was C plot<B plot<A plot, A plot was the most alkalined and C plot was the least alkalined. Thus, B plot kept better condition of soil and vegetation than A plotthough C plot had the best condition. It is considered that on the process of rehabilitation of degraded pasture land vegetation and soil are corresponding each other. On the saline meadow at site No. 4, a gypsum land plaster was applied to improve soil salinity 15 years ago (B plot). Vegetation and soil of B plot were compared with A plot (control). Vegetation of B plot had a higher plant height, coverage and standing crop than A plot. Moreover, it had fewer saline tolerant species. Soil of B plot had a lower pH and salts, and showed the remarkable improvement of the salinity. Besides, it had a higher content of the organic matter, available N and P, and fertile than A plot. Thus vegetation and soil were improved correspondingly by a gypsum land plaster. Considering the results of sites 1-4, the followings are pointed OUt. There is a high correlation coefficient, r= 0.97, between the organic matter and available N. Accumulation of the soil organic matter and the vegetation development are closely correlated. To diagnose the stages of recowery from desertified grasslands, not only the life form and the growth form of dominant species but also measurements of vegetation such as coverage, plant height, the number of annual and perennial species, and existence of degradation indicator speciesl etc. are effective.

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This study was conducted to investigate the effect of dissemination of seeds along with cattle dung on the propagation of Kentucky bluegrass (Poa pratensis L.). In this report, the results of experiments were presented on the comparison of recovery and viability of the seeds of Kentucky bluegrass and other two forage grass species passed through the digestive tract of cattle. In addition, the results of observation of the seasonal changes in the species and number of seeds in cattle dung on the pasture where is dominated by Kentucky bluegrass at the Alpine Region of the National Grassland Research Institute with about 1,200 m altitude in central Japan are reported. Each of three Japanese black cattle, whose body weight was 260-273 kg, was fed a mixture containing 250 g of seeds of each of Kentucky bluegrass, orchardgrass (Dactulis glomerata L.) and perennial ryegrass (Lolium perenne L.), and 2.5kg of concentrate feed. The maximum recovery of seeds occurred in the dung defecated within 24-48 hrs after feeding in all species, and 80-90% of the total recovered seeds were recovered in the first 72 hrs after feeding. The percentage of recovery was highest for Kentucky bluegrass (51.4%), followed by perennial ryegrass (47.7%), and orchardgrass (16.7%). By the passage of seeds through the digestive tract of cattle, the germination percentage decreased in every species. The percentage of germination of seeds recoyered was highest in Kentucky bluegrass(64.3%), lowest in orchardgrass (3.9%), and intermediate in perennial ryegrass (44.0%). Based on these results, it was concluded that Kentucky bluegrass is much more resilient after dissemination in cattle dung than the other two species. As a result of the investigation of the experimental pasture, 19 species of plants were observed. Among the species, the seeds of seven species of plants were observed in the dung pats on pasture. The number of seeds of Kentucky bluegrass was maximum in the dung pats. The seeds of Kentucky bluegrass were observed in the dung pats from the beginning of July to the middle of August, and maximum recovery occurred in the middle of July.

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In this report, the results of observation were presented on the seasonal recovery and viability of seeds of Kentucky bluegrass (Poa pratensis L.) in cattle dung on the pasture which is dominated by Kentucky bluegrass at the Alpine Region of the National Grassland Research Institute with about 1,200 m altitude in central Japan. In addition, the results of observation of the invasion pattern of Kentucky bluegrass to the sloping Sasa-type pasture with the seeds embedded in cattle dung at Sugadaira at situated an altitude of about 1,600 m in central Japan are reported. In the experimental pasture at the alpine region of the National Grassland Research Institute, the initiation of flowering and seed setting of Kentucky bluegrass were respectively observed in the middle and the end of June. The first recovery of the seeds in cattle dung was observed in the beginning of July. But the germination percentage of seeds recovered was only 12%. The maximum recovery occurred in the middle of July, when the germination percentage of the seeds reached 56%. Thereafter, the recovery decreased rapidly and it was finished in the middle of August. Based on these results, it was concluded that dissemination of seeds along with cattle dung was possiblefrom four weeks to eight weeks after the initiation of flowering. Vegetation of the experimental paddock at Sugadaira could be broadly divided into Zoysia and Sasa types. Major species that invaded from Zoysia-type to Sasa-type pasture through the seeds in cattle dung were Kentucky bluegrass, Japanese lawngrass (Zoysia japonica Steud.), timothy (Phlem pratense L.) and white clover (Trifolium repens L.). The number of seeds of Japanese lawngrass was maximum in the dung pats on pasture, however, Kentucky bluegrass was the highest in frequency and coverage in a Sasa plot set up in a Sasa-type pasture. In addition, a significant positive correlation was found between the coverage of invading plants and the coverage of dung pats, except for Japanese lawngrass. The coverage of dung pats was decreased with increasing the angle of pasture. The results revealed that invasion extent through the seeds in cattle dung was regulated by not only the number of seeds included in the dung pats but also the survival ability of invasion plants in existing colony.

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Early harvesting of timothy (TY)-white clover (WC) mixtures generally results in dominance of WC and decrease of TY density in Konsen district, Hokkaido. To clarify the cause of this decline in TY population, the relationships between productive structure and air dry matter accumulation during the regrowth after 1st cut of each cultivar (TY:c.v. Nosappu, WC:c.v. California ladino) was investigated. Two plots with different growing periods in 1 st and 2nd crops were set , the early harvest plot (EH, 1st cut at boot stage of TY and 2nd cut after 42-day-regrowth) and the control plot (CN, 1st cut at heading stage of TY and 2nd cut after 62-day-regrowth). There were differences in the regrowth of each cultivar between both plots at the 15th day after 1st CUt. Namely, the amount of TY regrowth and the density of TY tillers were suppressed in EH plot, while the amount of WC regrowth and the percentage of WC were promoted as compared with CN plot. Plant height of these two cultivars were similar in CN plot, but WC was taller than TY in EH plot at the 15th day after 1st cut. Also, relative light intensity in leaf layer of TY was low in EH plot. Therefore, it seemed that TY was much shaded by WC in EH plot. The amount of TY regrowth was lower and the percentage of WC was higher in EH plot than in CN plot at 2nd cut.From the above results, it was suggested that dominance of WC and decrease of TY density in early harvested TY- WC mixtures were caused by the suppression of sprouting of TY, the promotion of leaf expansion of WC and the shading of TY by WC at the early stage of regrowth after 1st cut.

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This experiment was designed for a better use of abandoned paddy fields which are increasing every year to prevent their devastation by cultivating waterhyacinth and using its harvested materials as fodder. The closed water system was chosen as an experimental field to cultivate waterhyacinth. For basal dressing at the plant transplanting, phosphorus ammonium chloride was applied to the water in the paddy to make various concentrations 0, 10, 20, 40, 80, and 100ppm of NH_4-N. The same equivalent weight fertilizer was added to the water every 10 days for 50 days. Sixty days after the transplanting,the plants were harvested to analyze their growth and uptake of nitrogen. The number of plants and DM (Dry Matter) weight showed their maximum values at 40 ppm NH_4-N. With the increase of NH_4-N level, DM weight % of roots of the plant decreased and N content (%) of the plants increased. As waterhyacinth grew, their roots penetrated into the soil, and then started to uptake nitrogen from the soil. The amount of N uptake by the plant from the soil decreased in accordance with the increase of NH_4-N levels.

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This study was conducted to clarify the effects of temperature on the fermentation quality, cell wall constituents and in vitro dry matter digestibility (IVDMD) of alfalfa silage with three additives of lactic acid bacteria (LAB), cellulase (CEL) and LAB-CEL mixture (MIX). Second-cut alfalfa was ensiled in 900ml bottles with these additives and without additive (control). Each bottle was stored in incubators at 20, 30 and 40℃. The improved fermentation quality was found in LAB and CEL silages stored at 20℃,and in MIX silages stored at all temperatures. The fermentation quality of all silages was improved as the temperature increased from 20 to 40℃. At all temperatures investigated, neutral detergent fiber (NDF) and acid detergent fiber (ADF) contents also tended to be reduced in CEL, particularly in MIX silages, as compared with control. In any silages with additive, the content of NDF and ADF was the lowest at 40℃, as compared with at 20 and 30℃. There were higher values for IVDMD in LAB and MIX silages than the control while lower in CEL silages at any temperatures investigated. In any silage with additive, IVDMD increased as the temperature increased from 20 to 40℃The fermentation quality of alfalfa silage correlated with their cell wall components and IVDMD.

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Dactylis glomerata is one of the most common grass species in Hokkaido island, Japan. This species frequently establishes natural populations in open habitats such as bare grounds and road sides in Hokkaido. In this study, geographical distribution and genetic differentiation were examined for natural populations at 43 sites of Hokkaido which are available for meteological data. The results obtained are as follows: (1) The survey of frequency at 43 sites showed that the abundance of the natural populations decreased in North-Eastern part of Hokkaido. The fre- quency showed a high positive correlation with the lowest temperature before snow cover more than 10 Cm. (2) When plants derived from seeds were compared under an experimental field, plant type tended to show a close relation with the frequency. The populations from the sites with High (>90%) and Low (<60%) frequency had more smaller tillers than those with Middle (60-90%) frequency. (3) The population with Low frequency tended to show low fall growth and high dry matter content, although the differences were not significant.

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