Text and photos: Juha Siekkinen, Life+ Return of Rural Wetlands Cover drawing: Jari Kostet Maps and aerial photos: National Land Survey of Finland

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1 Life+ Return of Rural Wetlands Pikku Nuoluanjärvi Wetlands, Liminka Text and photos: Juha Siekkinen, Life+ Return of Rural Wetlands Cover drawing: Jari Kostet Maps and aerial photos: National Land Survey of Finland 1

2 The objectives of Pikku Nuoluanjärvi wetlands The objectives are to Improve water quality of ditched forestry areas by binding sediments and nutrients Create habitats for wetland fauna, in particular for waterfowl Promote biodiversity, landscape and multifunctional land use Imitate beaver flooding in wetland restoration Act as demonstrative site of wetland work in the region Background Pikku Nuoluanjärvi wetlands consist of two basins ( The Northern wetland and The Southern wetland ) situated side by side divided by the five meters wide ditch The Northern wetland: built by damming the water to a higher level. Total wetland area is 4,5 hectares of which total area of open water is 2 hectares. No tree felling imitating of beaver flooding. The catchment area is 100 hectares dominated by peatlands and forestry. The Southern wetland: built by damming the water to a higher level. Total wetland area is 4,5 hectares (almost all open water). The catchment area is 735 hectares dominated by intensive forestry. The wetland project was designed and financied in collaboration with Vapo Oy, Centre for Economic Development, Transport and the Environment, The Finnish Forest Centre and Life+ Return of Rural Wetlands

3 The situation of Pikku Nuoluanjärvi wetlands The closest address is Paavolantie 125, Liminka (600 m from the Southern wetland). Car parking is 100 m from the Southern wetland. More information and site presentations in the field Finnish Wildlife Agency: Juha Siekkinen , juha.siekkinen@riista.fi (in english) Vapo Oy: Kari Väisänen tel , kari.vaisanen@vapo.fi (in finnish)

4 Two wetland consists of two basins side by side. The basins are not connected to each other Between the basins there are the five meter wide man-made channel THE NORTHERN WETLAND (4,5 HA) Notice board THE SOUTHERN WETLAND (4,5 HA)

5 Laser scanning image of Pikku Nuoluanjärvi area Pikku Nuoluanjärvi was a shallow lake still in the beginning of 20th century Legend below right: numbers indicate the elevation of ground in meters above sea level National Land Survey of Finland and The Finnish Forest Centre

6 The catchment areas of Pikku Nuoluanjärvi wetlands

7 Pikku Nuoluanjärvi Wetlands Restoration Project Description Map

8 Pikku Nuoluanjärvi wetlands before the restoration activities Northern wetland area was dominated by deciduous trees like birch and alder. Many trees were dying because of wet ground and seasonal flooding.

9 Pikku Nuoluanjärvi wetlands before the restoration activities Southern wetland area was dominated by deciduous trees like birch. In the western part there were an open area covered by shrubs, a total of 1,5 hectares (photo below).

10 Logging process in the northern wetland Tree felling were conducted along channel in mid-april The excavator New Holland Kobelco E 135 was equipped with the energy wood harvester head (quillotine cutting method). The contractor was Koneurakointi Lasse Kerälä Company (L. Kerälä in photo)

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12 Before Afterward

13 Logging process in the southern wetland Tree felling were conducted in the beginning of april Clear-cutting were done by John Deere 970d wheeled harvester cm snowcover ensured a gentle footprint on the wetland and forest floor. All log transportation were done by Timberjack 1110 D forwarder The contractor was Koneurakointi Lasse Kerälä Company (Taavo Robert in photo)

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15 Water control structure in the northern wetland Water control structure, a half-round flashboard riser was constructed to the east side of the wetland in mid-february 2013 Flashboard riser is made from steel and has been attached to highdensity polyethylene pipe. This combination has several advantages: they are lightweight, easy to transport and to control water level is easy and accurate. Water levels is regulated by placing or removing logs in the control slots to the desired elevation. Stoplogs are made of Siberian larch

16 First, turf were excated away so that is was possible to ground a steady basis for the HDPE pipe and the flashboard riser combination. The riser were not anchored e.g. in an unmovable concrete foundation

17 The riser was attached to the HPDE pipe with screws and fastened with polyurethane foam

18 Finally, the filtering cloth was settled with carefully all over the riser, especially in front below to prevent leakages. The embankments around the riser were constructed afterward.

19 Water control structures in the southern wetland Water control structure, the overflow dam with wooden wall was constructed to the east side of the southern wetland in mid-february 2013 First, a frozen ground were excavated so that wooden timber were able to press in ground. Stoplogs are made of Siberian larch for its durable and waterproof qualities.

20 Larch logs in stand were mounted with steel bolts every one meter to the horizontal larch logs. Furthermore every logs in stand were nailed to the horizontal larch logs. The height of wall outlet was sawed to the desired lowest water level. With movable logs water level is possible to increase up to 50 cm

21 The downstream was excavated and covered with filtering cloth and rocks from 5-30 cm

22 The embankments around the overflow dam were constructed afterward. In may 2013 the embankments near wooden wall had to be fixed due to leakages caused by spring flood. Repair actions were conducted by Matti Kylmänen In late summer 2013 the embankments was covered mainly with natural vegetation and had worked well

23 The embankments were constructed in february and march in 2013 First, all woody vegetation and surface turf were removed from the centerline: the core trench is one meter width and cm deep. Only unfrozen fine-textured soils like silt-clay, silt or clay were used to form a tight seal with the soil already there. Embankment constructions

24 Soil for the embankment were borrowed next to the embankments The borrow areas situate 4-5 m away from the base of the embankment to prevent sloughing or caving material away from the embankment. The borrow areas are rather wide and shallow. They will generate new, a deeper wetland microhabitats near the shallower wetland habitats (both photos are photographed from same site) Juha Siekkinen Juha Siekkinen

25 Photo above ( ) The embankments were constructed with 1:2 slopes. The top width of the embankments is 1-1,5 m. The embankments were lined with surface turf. The aim of this is to facilitate management in future like prevent tree establisment. Photo below ( ): Covered embankments will landscape already during the first summer

26 The Northern wetland of Pikku Nuoluanjärvi From degraded wetland to restorated, beaver-pond simulated wetland Above: , before restoration, below after logging along canal sides in left. Juha Siekkinen

27 Above: after all restoration actions, below Juha Siekkinen

28 Above: , below:

29 The Southern wetland of Pikku Nuoluanjärvi From degraded wetland to restorated open water wetland Above: , logging done. Below after restoration actions Juha Siekkinen