Maruyama Marsh Group
Maruyama Marshland Group (Maruyama Shitsugengun) is a general term for five spring marshes in the hills in the northern part of Takarazuka City, Hyogo Prefecture. The largest marshland with an area of over 2,000 square meters is the largest marshland in Hyogo prefecture, and was designated as a natural monument in Takarazuka City in 2014 and a natural monument in Hyogo Prefecture in 2015.
On the east side of the Sengari water source pond in the northwestern part of Takarazuka city, there is a hilly area that straddles the Sakaino, Tamase, and Hazu districts. The Maruyama Marsh Group refers to five marshes scattered on the southwest side of "Maruyama" at an altitude of about 330 meters in the hills, and the total area reaches about 4,000 square meters. Selected as A rank in the Hyogo Prefecture Red Data Book (category: plant community), the first edition of which was created in 1995, because it is excellent in scale and quality, has the highest degree of value, and is equivalent to national value. It has also been registered as an important wetland of the Ministry of the Environment . In addition, the Nishiya area, including the Maruyama Marsh Group, is registered as an important Satochi Satoyama by the Ministry of the Environment . In the 2011 survey, 45 of the 54 species of marshland plants from Hyogo Prefecture were confirmed, and endangered white egret flowers and oysters can be observed in the plants, and the animals such as Nepa hoffmanni, Hynobius nebulosa, and Scarlet dwarf inhabit. It is important as a place to conserve endangered species. For this reason, the Maruyama Marsh Group and its surrounding area of 71.3 hectares were designated as Takarazuka City in 2014 and as a natural monument in Hyogo Prefecture in 2015. In addition, in order to maintain the ecosystem of the wetland, the "Maruyama Wetland Group Conservation Society" was established in 2006 by local residents and other local residents, and is carrying out regular conservation activities. In 2008, the conservation of the wetland was carried out. The "Maruyama Raised Bog Ecomuseum Promotion Council" was established in cooperation with local residents, the government, and academics as an organization to decide the utilization policy.
Since the Maruyama Marsh Group is located in the valley of the hills, the surface of the marsh is not flat like the Kushiro Wetland but slopes gently. If you walk from the parking lot, you will first pass through the third marsh (about 310 square meters) with a wooden path, and the next largest area, the first marsh (about 2,230 square meters), has an observatory in the marsh, inside the marsh. Can be observed well. Below the first bog is the fourth bog (about 610 square meters), from which the water of the bog flows down the valley to the Kawashimogawa Dam. These three marshes are in one valley, but the second marsh (about 730 square meters) is in the next valley beyond the ridge to the west of this valley, from the observatory on the ridge to the valley. You can observe the marshland. The small Raised Bog (about 50 square meters) is on the way to Oiwadake on the north side.
The origin of the Maruyama Marsh Group
In the large-scale high moors found in the cool regions of northern Honshu and Hokkaido, the peat layers on the surface form a water-retaining layer to maintain moist soil. However, there is no peat layer in the spring marsh formed in warm regions. It was human activity that formed and sustained the Maruyama Marsh Group.
Raised bog is established by human activities
The Maruyama Marsh Group is formed on the bottom of a wide, gently sloping valley, and a stratum mainly composed of silt with poor permeability is deposited to a depth of about 1 meter. From the analysis results of the plant fragments in the deepest part of the marsh, it is estimated that the Maruyama Marsh Group was established in the Edo period 300-400 years ago. It is said that it was during the Edo period that satoyama became actively used to secure fuel and fertilizer, and the bushes and fallen leaves were cut, and the satoyama began to become bald. Many reservoirs were created in the Nishiya area, where the Maruyama Marsh Group is located, from the end of the Warring States period to the beginning of the Edo period.