Dataset associated with floodplain large wood and organic matter jam formation after a large flood: investigating the influence of floodplain forest stand characteristics and river corridor morphology

• Main Authors: Polvi, Lina E., Lininger, Katherine
• Format: Dataset
• Language: unknown
• Published: University of Colorado Boulder 2020
• Subjects: Northern Sweden
• Online Access: https://dx.doi.org/10.25810/6ycq-ek62; https://scholar.colorado.edu/concern/datasets/1c18dg65s

River corridors play an important role in the carbon cycle as sites of carbon transport, storage, and transformation. Floodplain soil organic carbon (OC) and dead, downed large wood (LW) are two of the largest OC stocks in rivers. Human modifications of river corridors, such as damming and floodplain land-use change, have likely modified floodplain OC storage and retention. We measured floodplain soil OC and downed LW loads on three rivers in northern Sweden that display a gradient in the degree of human alteration. The Muddus River is located in a national park and is unaltered. The Vindel River is free-flowing but has been modified via logging and other land-use changes within the floodplain. The Ume River is dammed along its length and has also experienced floodplain logging and land-use change. We used statistical models to determine which factors are associated with differences in soil OC and LW among rivers with different degrees of human alteration. We find the highest soil OC concentrations on the unaltered Muddus River (mean = 3.70%; median = 3.81%), with lower soil OC along the Vindel (mean = 1.44%; median = 0.72%) and Ume (mean = 2.47%; median = 1.12%) Rivers. The Muddus River also has the highest downed LW loads (mean = 22.25 m3 ha-1) compared to the Vindel (mean = 3.10 m3 ha-1) and Ume (mean = 7.26 m3 ha-1) Rivers. Variations in soil OC and downed large wood loads indicate that damming may reduce floodplain OC in these boreal systems through reducing lateral channel-floodplain connectivity and longitudinal connectivity. Logging and other land-use changes likely reduce OC inputs to the floodplain surface through removal of organic matter and LW. Further research is needed to elucidate the impact of human modifications on floodplain OC across diverse regions. This dataset is presented and described in the article: Lininger, K.B., and L.E. Polvi. In review. Evaluating floodplain organic carbon across a gradient of human alteration in the boreal zone. These data describe soil organic carbon concentrations, soil organic carbon stocks, and downed large wood loads in the floodplains of the Muddus, Vindel, and Ume Rivers in northern Sweden. Fieldwork was conducted in Summer 2016, and laboratory work was conducted in 2017 and 2018.