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We provide a novel analysis of the locomotor movements of athletes in the National Rugby League Women's (NRLW) competition by presenting the data of opposing teams expressed as a relative (%) difference and explore the association with match outcome. 117 rugby league athletes from the four NRLW clubs participated in this study. Mean speed (m·min−1), mean high-speed running (>12 km·h−1; m·min−1), and mean acceleration (m·s−2) were measured in 12 matches (370 individual match files) using the Global Navigation Satellite System (GNSS). Individual GNSS-derived data from each match-half were summed across each team and the association with total points and the points differential in each match-half was determined using linear mixed models. Greater high-speed running and lower mean acceleration were associated with more points being scored. A greater relative difference in mean high-speed running between competing teams was associated with a higher points differential. That is, if a team completed 10% more high-speed running than their opposition, they were likely to score an average of 3.2 points more during a given match-half. This unique analysis of GNSS-derived data may assist coaches and performance support staff to interpret the locomotor movements of female rugby league players with the appropriate considerations for the opposition team. [ABSTRACT FROM AUTHOR]

Eutrophication has degraded ecosystem, cultural and recreational values in Lake Forsyth, a small, shallow, coastal lake in New Zealand. To inform catchment management decisions designed to prevent algal blooms and improve water quality, a sub-catchment scale, mass-balance approach to understanding the behaviour of the critical nutrient, phosphorous (P), has been taken. To determine a P budget for the lake, and identify key P reservoirs, hydrological inflows and outflows were measured over a 15 month period. These were combined with total (TP) and dissolved reactive P (DRP) concentrations in these flows, to determine the external load of P transported to the lake. Lake water was also analysed for TP and DRP concentrations, and chemical extractions were used to determine the mass and mobility of P in the lake sediments. Biomass surveys and chemical digestions were used to quantify the mass of P contained in lake macrophytes. Changes in the lake water P reservoirs were then used to assess the contribution of external P loading relative to fluxes of P from the sediment to the lake water column (internal P loading). More than 7000 kg P per year was delivered to the lake, 68% of which came from a single sub-catchment. P associated with suspended particulate material accounted for 80% of the external P load transported into the lake and 61% of the load delivered over the study period was transported during a single flood event. A reduction of 53% in the external P load is necessary to achieve a recommended areal loading guideline. As the lake has no permanent outflow, this external load and the low flushing rates have created a large legacy reservoir of P in the lake sediments with 70% of external P loads retained in the lake. It is the release of P from these lake sediments rather than fluctuations in external loading that control P concentrations in the lake water column during the blooms of nitrogen-fixing cyanobacteria. The results indicate the importance of targeting both external and internal loading processes in the catchment. The sub-catchment scale, mass-balance approach to determining a P budget and quantifying P reservoirs enable critical source areas for external P loads to be identified, and the potential efficacy of targeted interventions to reduce P sources and minimise P transport, such as wetlands and sediment retention basins, to be assessed. [ABSTRACT FROM AUTHOR]

Sediment release rates of soluble reactive phosphorus (SRP) and ammonium (NH4) were determined seasonally at three sites (water depth 7, 14 and 20 m) in Lake Rotorua using in situ benthic chamber incubations. Rates of release of SRP ranged from 2.2 to 85.6 mg P m−2 d−1 and were largely independent of dissolved oxygen (DO) concentration. Two phases of NH4 release were observed in the chamber incubations; high initial rates of up to 2,200 mg N m−2 d−1 in the first 12 h of deployment followed by lower rates of up to 270 mg N m−2 d−1 in the remaining 36 h of deployment. Releases of SRP and NH4 were highest in summer and at the deepest of the three sites. High organic matter supply rates to the sediments may be important for sustaining high rates of sediment nutrient release. A nutrient budget of Lake Rotorua indicates that internal nutrient sources derived from benthic fluxes are more important than external nutrient sources to the lake. [ABSTRACT FROM AUTHOR]