Poor water quality (high concentrations of nitrogen (N), phosphorus (P), suspended solids (SS), and faecal bacteria) in Waiokura Stream, southern Taranaki, New Zealand, is attributed to diffuse and point source (PS) inputs from dairy farming. Trend analysis of concentration time‐series data (2001–2008) and annual yields (i.e., stream load divided by catchment area) showed that significant improvements occurring since 2001 may...

At the catchment scale, braided rivers are recognised as physically unstable, dynamic landscapes, yet at finer spatial scales they are a mosaic of micro‐habitats including physically unstable braided channels and more stable spring‐sources, spring creeks, and groundwater zones. We investigated benthic invertebrate communities at 103 sites in braided channels, springs and hillslope streams in the Waimakariri River, New Zealand...

Six small constructed ponds (surface area 500–7500 m 2 , catchment area 28–158 ha) in rural and native forest catchments in the Auckland region had poorer water quality than the streams they replaced. Temperature (24°C) and dissolved oxygen (DO) (4 mg/litre) criteria were exceeded for up to 46% and 84% of days, respectively, during a critical 40‐day summer period. The poor conditions found in ponds, even within undeveloped nat...

River water quality in New Zealand is at great risk of impairment in low elevation catchments because of pervasive land‐use changes, yet there has been no nationwide assessment of the state of these rivers. Data from the surface‐water monitoring programmes of 15 regional councils and unitary authorities, and the National River Water Quality Network were used to assess the recent state (1998–2002) and trends (1996–2002) in wate...

Macroinvertebrate communities in hard‐bottomed (HB) and soft‐bottomed (SB) streams were compared to address questions on sample substrata, sample area, and data interpretation. Communities at HB and SB reference sites (native bush catchments) were distinctly different. SB reference sites had 50% of the total taxa, 33% of the Ephemeroptera, Plecoptera, and Trichoptera (EPT) taxa, and significantly lower Macroinvertebrate Commun...

We compared the performance of fixed count subsampling (100, 200, and 300 individuals) and coded abundance (rare, common, abundant, very abundant, very very abundant) with full count sampling for rapid assessment biomonitoring. Examining change in the Quantitative Macroin‐vertebrate Community Index (QMCI) and % Ephemeroptera, Plecoptera, and Trichoptera (EPT) values between sites upstream and downstream of pollution inputs, we...

The influence of hydraulic exchange patterns on hyporheic water chemistry and invertebrate community composition was measured in three gravel‐bed rivers of southern Hawke's Bay, North Island, New Zealand. Based on patterns reported overseas we predict that down‐welling waters will be similar to surface waters in chemical characteristics and epigean animals will be more common in down‐welling waters than in up‐wellings, which w...

Aquatic macroinvertebrates were sampled annually at 66 sites of the National Rivers Water Quality Network (NRWQN) from 1989 to 1996. At each site, temporal trends in number of taxa, total abundance, Macroinvertebrate Community Index (MCI), the quantitative version of MCI (QMCI), number and percent of Ephemeroptera, Plecoptera, and Trichoptera, Shannon's Diversity Index (H'), Jaccard's similarity index, and Bray‐Curtis similari...

Three first‐order, hill country, pasture streams in Waikato, New Zealand, were chosen to investigate the effects of patches of late‐succession indigenous riparian forest on water quality, epilithon, stream morphology, and aquatic macro‐invertebrates. Sites were situated in open pasture and at two distances (c. 50 and 300 m) into a forest remnant on each stream. Shade, channel width, and epilithon biomass were restored to condi...

Although the importance of the subsurface saturated interstitial zone (hyporheic zone) to the ecological functioning and maintenance of water quality of stream ecosystems is well known, there is little information on the impacts of different forms of land use upon this zone. Hyporheic physico‐chemistry and invertebrates were compared among small streams draining hill‐country catchments under pasture, exotic pine forest, and na...