, 2003), but here the effects were closest to the pumping well P

, 2003), but here the effects were closest to the pumping well. Pumping in 2004, 2007, 2008, and 2009, all years with below average SWE and the snowpack melting in early to middle March, resulted in the water table declining to the base of the peat body by mid summer. The water table decline produced dry soil conditions and peat cracking, which has allowed upland plants such as Poa pratensis to invade

the peatland. The rapid daily water table decline each day due to pumping was only partially matched by the water table rise after pumping ceased. This suggests that by mid- to late- growing season during dry years, such as 2004, insufficient groundwater inflow occurred OSI-744 concentration to offset the amount of water removed by pumping and to maintain the meadow water table near the soil surface. This was in contrast to reference fens during the same time periods where the water table remained within 20–40 cm of the soil surface. Pumping in 2005, 2006, and 2010, all years with higher SWE and later melting snowpack, resulted in little water level drawdown despite a nearly identical pumping schedule in those years. For Ribociclib in vivo example, in the large snowpack year 2005, the season-long effects of pumping were mitigated by higher groundwater recharge that maintained fen water levels near the ground surface. Nearly all of the produced water from the Crane Flat pumping well is drawn

from shallow (<28 m depth) sediments. This extraction produces an almost immediate hydraulic head decline in the conductive sands that underlie the peat body. The amount of drawdown is dependent on the pre-pumping head level. When the hydraulic head is above 70 cm bgs, increased drawdown is observed for lower initial head levels. We interpret this as a signal of increasing peat density with depth, and a resultant decrease in pore size and free-draining water content (specific yield). For initial head levels lower than 70 cm bgs, total drawdown is less sensitive to the initial

hydraulic head, although the negative correlation between initial head and drawdown magnitude may indicate greater porosities within the sand and gravel compared to the deep peat. Fens in the Sierra Nevada, such as Crane Flat, have formed over thousands of years, due to the accumulation of partially Cediranib (AZD2171) decomposed plant litter (Bartolome et al., 1990). This has occurred where inflowing groundwater maintains the water table near the soil surface even on average to dry water years (Chimner and Cooper, 2003). Water table declines produced by ditching (Cooper et al., 1998), or water extraction such as groundwater pumping, can lead to rapid peat oxidation, erosion and subsidence (Schumann and Joosten, 2008 and Schimelpfenig et al., 2013). Hydrologic changes have allowed the invasion of small mammals into Crane Flat, including pocket gophers and voles.

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