With the extension of railroads in the late 1800s, homesteader settled in western reaches of the Great Plains known as the High Plains. They cultivated wheat, milo, and millets in spite of blizzards, hail, tornados, and droughts. Grain farming in the semiarid region resulted in severe soil erosion. Because of dust storm in the 1930s, the federal government established the Soil Conservation Service, now known as the Natural Resources Conservation Service. Soil Conservation Districts were organized at the county level and encouraged such dryland farming practices as strip cropping, contour cultivation, and stubble mulching. Following decades of various environmental conservation policies, Congress passed the Food Security Act of 1985 that included the Conservation Reserve Program (CRP). This study examines the development of CRP with reference to the land erodibility and grain farming in Kearny County, Kansas.
Under the CRP, farmers received approximately 50 dollars per acre for converting the cropland to natural grassland between ten and fifteen years. More than 31 million acres of croplands are enrolled in CRP in the United States, and 44% of them are distributed in the High Plains States such as Texas, Kansas, Colorado, Nebraska, Oklahoma and New Mexico. CRP land in the High Plains is concentrated in the western edge of the Winter Wheat region, once called the suitcase farming frontier, where absentee landlords cultivated exclusively wheat in favorable rainfall year. Since wheat and milo are cultivated with summer fallow rotation systems in the dry farming region, cash crops are only produced once in two years or twice in three years at each cropland unit.
The distribution of CRP land in Kearny County is related to the capability unit of soil erosion. The land of highest erodibility such as valley slopes and sandy soil is used as a rangeland, and most CRP land is distributed around it. It receives limited and fewer groundwaters from Ogallala Aquifer. CRP land is also distributed at the corners of center-pivot irrigation systems in the eastern part of the county, where cultivation of corn and alfalfa is common. CRP is widely accepted by farmers because the annual rental payments (36 dollars per acre) often result in a higher profit than the revenue of grain farming with fallow and the rent of non-irrigated land. The contract farmers consider CRP as one of the most profitable use of arable land.
The CRP land covered with natural grasses such as big bluestem and switchgrass is beneficial not only for reducing soil erosion, but also for fostering the wildlife habitat. During winter months in the dry farming region, a lot of cropland is either fallowed or planted with small wheat. CRP grassland is a suitable habitat and hiding place for big game such as deer, especially in winter. In the semi-arid High Plains regions, CRP grassland sustains the dry farming and preserves the natural environment.

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The Japan-Sea side region is known as much monsoonal rainfall, and there are regional differences of year-to-year variation in this region, but reasons for these are not investigated sufficiently. In this paper, at first, the Japan-Sea side region is divided into four subregions; ‘Hokkaido’, ‘Tohoku’, ‘Hokuriku’ and ‘San-in’.
Next, in each region, the relationship between rainfall and monsoon, and the relationship between rainfall and depression activities are examined. Monsoon Index (MOI) is difined as the 1, 000hPa heights difference between four pairs of points on different parallels of latitude over Japan Islands, and depression activities are shown as the distribution of depressions' passage frequencies.
The results are summarized as follows;
1) In ‘Hokkaido’ and ‘Hokuriku’, the main factor of rainfall variations is monsoon, while in ‘Tohoku’, it is Japan-Sea lows, and in ‘San-in’, it is Paciffic lows.
2) The rainfall variations' difference between ‘Hokkaido’ and ‘Hokuriku’ is caused by the secondary factor; that is Japan-Sea lows.
3) The relationship between rainfall and sea level pressure field or 500hPa height field correspond to the relationship between rainfall and the year-to-year rainfall variation factors such as monsoon and depression activities.

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A peaty soil layer is frequently observed on the alpine and subalpine slopes of snowy mountains in central and northern Honshu, Japan. The genesis of the peaty soil layer is closely related to ground surface stability, plant succession and hydrological condition on these slopes. Therefore, the peaty soil layer plays an important role in reconstructing paleoenvironment in the snowy mountains. In particular, the data on the initiation of the peaty soil layer can be regarded as the significant evidence of the landscape change since the Last Glacial age. However, the previous studies on the peaty soil layer have rarely presented the precise age when the formation of such a soil layer was initiated.
The following two opinions were previously presented on the initiation age of the soil layer in the subalpine slopes of Mount Tairappyo (36°48′N, 138°49′E; 1, 984m a. s. l.). One is that the peaty soil layer began to develop in the late Holocene, and the other is that initiation age of the soil layer considered to be older than the middle Holocene. The discrepancy causes large confusion in the paleoenvironmental interpretation in this area.
This paper aims to clarify the initiation age of the peaty soil layer in the subalpine zone of Mount Tairappyo.
The results are summarized as follows:
1) The peaty soil layer is approximately 50cm thick, and extensively covers fossil snowpatch hollows and fossil periglacial smooth slopes. 2) The peaty soil layer commonly intercalates the middle Holocene tephra layers such as the Kikai-Akahoya (7, 200cal y BP), the Myoko-Akakura (6, 600cal y BP), the Asama-Tairappyosan 3 (6, 600cal y BP) and the Asama-Tairappyosan 2 (6, 300cal y BP) in its lower part. 3) The age of the boundary between the peaty soil layer and the underlying slope deposits is tephrochronologically determined as 8, 000 to 7, 000cal y BP in most parts of the study area, even those fossil snowpatch hollows where snow disappears latest in this area. The peaty soil layer which was formed in the early to the middle Holocene is, however, lacking in a restricted central part of fossil snowpatch hollows. 4) The peaty soil layer began to accumulate in the whole area, except for the central part of fossil snow patch hollows, by 8, 000 to 7, 000cal y BP. Periglacial and nivation processes became less active by 8, 000 to 7, 000cal y BP.

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