ABSTRACT. Recent freshwater policy reforms in New Zealand promote increased community involvement in freshwater decision making and management. Involving community members in scientific monitoring increases both their knowledge and their ability to discuss this knowledge with professionals, potentially increasing their influence in decision-making processes. However, these interactions rarely occur because, in particular, of perceptions that volunteer-collected data are unreliable. We assessed the agreement between volunteer (community group) and local government (regional council) data at nine stream sites across New Zealand. Over 18 months, community groups and regional council staff monitored, in parallel, a common set of water quality variables, physical habitat, periphyton and benthic macroinvertebrates that are routinely used by regional councils for statutory state of environment reporting. Community groups achieved close agreement (correlations ≥ 0.89, bias < 1%) with regional councils for temperature, electrical conductivity, visual water clarity, and Escherichia coli. For dissolved oxygen, nitrate, and pH, correlations were weaker (0.2, 0.53, and 0.4, respectively). Volunteer assessments of physical habitat were as consistent over time as those of councils. For visual assessments of thick periphyton growths (% streambed cover), volunteers achieved a correlation of 0.93 and bias of 0.1% relative to councils. And for a macroinvertebrate biotic index that indicates water and habitat quality, correlation was 0.88, bias was < 5%, and the average difference was 12% of the index score. Volunteers showed increased awareness of local freshwaters, understanding of stream ecosystems, and attentiveness to local and national freshwater issues. Most volunteers had shared their knowledge and interest with others in their community. Most groups had developed relationships with their regional council, and some volunteers became more interested in engaging in freshwater decision making. Given adequate professional support, community-based water monitoring can provide data reliable enough to augment professionally collected data, and increase the opportunities, confidence, and skills of community members to engage in freshwater decision making.

No abstract

We surveyed the amount and geomorphic role of wood in 18 pristine native forest streams (channel width: 3-6 m) throughout New Zealand, and quantified the characteristics associated with piece stability and geomorphic effect. Wood piece numbers (18-66 per 100 m) and volumes (85-470 m 3 ha -1) were similar to or greater than found in many streams throughout the world. Forest type and geographic location had no discernable influence on wood abundance at a particular site, possibly due to the confounding influences of local features (e.g., tree fall regime) and methodology ('snap-shot' survey of a dynamic system). Half the pieces that were geomorphically active had moved, suggesting that stable pieces did not necessarily dominate geomorphic activity. Tree ferns were an important contributor to wood abundance in many of the streams studied. IntroductionNumerous studies have characterized the amount (volume, density, or biomass) (HAR- MON et al., 1986;HERING et al., 2000) and role of wood in stream (TRISKA and CROMACK, 1980;BILBY and BISSON, 1998). Initially, much of this research was conducted in the Pacific Northwest of North America (LAMMEL, 1972;FROEHLICH, 1973; see GREGORY, 2003 for a review), but has since been conducted in other regions in the USA (e.g., New England, BILBY and LIKENS, 1980; Georgia, WALLACE and BENKE, 1984; Wyoming, YOUNG, 1994; Colorado, RICHMOND and FAUSCH, 1995), and throughout the world (e.g., New Zealand, MOSLEY, 1981; Australia, GIPPEL et al., 1996; France and the United Kingdom, PIEGAY and GURNELL, 1997; Central Europe, HERING et al., 2000). A conclusion common to many of these studies is that wood is an important component of forest stream ecosystems. Wood in streams can influence channel morphology, hydraulics and sedimentation patterns, which in turn influence nutrient dynamics and habitat for aquatic organisms (BISSON et al., 1987; see GREGORY et al., 2003a for a recent review).The abundance and functional importance of wood appears to vary by region, possibly due to characteristics of the riparian forest species (e.g., maximum tree height) and regional hydrology (GURNELL et al., 2002). For example, streams located in the redwood-dominated forests of northern California contain large volumes of wood (up to 4360 m 3 ha -1) that exert tremendous influence on channel morphology (KELLER and TALLY, 1979;KELLER et al., 1995). In contrast, streams in the coniferous forests of central Sierra Nevada, California (only 400 km southeast of the redwood study streams) have relatively low amounts of wood (up to 89 m 3 ha -1), which exerted only a minor influence on stream morphology (BERG et al., 1998).

Abstract. Five streams in catchments with pastoral dairy farming as the dominant land use were monitored for periods of 7-16 years to detect changes in response to adoption of best management practices (BMPs). Stream water quality was degraded at the start with respect to N, P, suspended solids (SS) and E. coli concentrations, and was typical of catchments with intensive pastoral agriculture land use. Trend analysis showed a decrease in SS concentration for all streams, generally increasing water clarity, and lower E. coli concentrations in three of the streams. These are attributed to improved stream fencing (cattle exclusion) and greater use of irrigation for treated effluent disposal with less reliance on pond systems discharging to streams. Linkages between water quality and farm actions based on survey data were used to develop BMPs that were discussed at stakeholder workshops. Generic and specific BMPs were developed for the five catchments. The 3-7 year periodicity of major climate cycles, as well as market forces and a slow rate of farmer adoption of simple BMPs mean that monitoring programs in New Zealand need to be much longer than 10 years to detect changes caused by farmer actions. Long-term monitoring is also needed to detect responses to newly legislated requirements for improved water quality.

No abstract