Phosphorus retention in streams draining pine and hardwood catchments in the southern Appalachian Mountains

Abstract

1. This study was designed to determine how catchment use affects stream phosphorus retention by comparing retention in streams draining three mixed hardwood catchments and three catchments that were planted in white pine in the 1950s.2. Catchments of similar area and stream discharge were chosen and phosphorus uptake was measured monthly in each catchment along with temperature, discharge, velocity, coarse particulate organic matter (CPOM), fine particulate organic matter (FPOM), and microbial respiration associated with FPOM.3. On an annual basis, average phosphorus retention was not different between streams draining pine and hardwood catchments nor were there significant differences between physical (temperature, velocity and discharge) or biological (CPOM, FPOM and respiration) parameters based on catchment type. However, discharge was more variable in streams draining pine catchments.4. Because phosphorus uptake was correlated with discharge, phosphorus retention was also more variable in streams draining pine catchments. Storms caused a greater increar.e in discharge and loss of phosphorus in pine streams than in mixed hardwood streams, but discharge returned to baseline more quickly in pine streams. 5. We suggest that discharge regimes and phosphorus dynamics of streams draining pine catchments are less resistant to change but more resilient than streams draining mixed hardwood forests.

Stream Nutrient Retention in Three Northeastern Oklahoma Agricultural Catchments

“…Variations in S w within or among seasons are often the result of variation in discharge (Butturini and Sabater, 1998), and several investigations have found positive relations between S w and velocity and/or discharge (see D'Angelo and Webster, 1991;Martí and Sabater, 1996;Valett et al, 1996). Similar to these existing reports, S w -SRP was shortest when discharge was lowest at all sites, and it became longer at higher discharges ( fig.…”

“…Several studies have shown spatial variation in S w within and among streams (Aumen et al, 1990;D'Angelo and Webster, 1991;Martí and Sabater, 1996;Munn and Meyer, 1990), and others have examined temporal variation in S w (Martí and Sabater, 1996;Mulholland et al, 1985;Webster et al, 1991). Spatial variation may result from differences in channel form, local environmental conditions, watershed land use, and physiographic features, whereas temporal variation is largely related to temperature, hydrology, and allochthonous inputs into the stream ecosystem.…”

Phosphorus Retention in Streams and Wetlands: A Review

“…Dissolved inorganic P is considered bioavailable, whereas organic and particulate P forms generally must undergo transformations to inorganic forms before being considered bioavailable. Other researchers have proposed three size fractions of P: dissolved (DP, < 0.45 µ m), fine particulate (FPP, 0.45 µ m to 1 mm), and course particulate (CPP > 1 mm) (D'Angelo and Webster, 1991) to help define sedimentation, transportability, and reactivity. However, these size fractions of P are not necessarily indicative of P bioavailability or chemistry.…”

Estimation of stream nutrient uptake from nutrient addition experiments

“…Usually the majority of spiraling length is uptake length, the average distance a nutrient atom travels in dissolved inorganic form before it is immobilized by either biotic or abiotic processes (Ball and Hooper 1963;Stream Solute Workshop 1990;Newbold 1992). In addition to extensive use in studies of relatively undisturbed streams (e.g., Webster et al 2003), nutrient uptake length has been used to measure stream response to forest and riparian management D'Angelo and Webster 1991;Sabater et al 2000;Valett et al 2002), waste water treatment plant effluent (Haggard et al 2001), and dam removal (Doyle et al 2003 Ball and Hooper (1963). Elwood and others used radioactive phosphorus as a tracer to measure uptake of phosphorus in Walker Branch, TN (Elwood and Nelson 1972;Newbold et al 1983;Mulholland et al 1985), and similar studies of phosphorus have been conducted at a few other sites (e.g., Gregory 1978;Hart et al 1991;Mulholland et al1997).…”