Improving the economic and environmental performance of a New Zealand hill country farm catchment: 3. Short‐term outcomes of land‐use change

Abstract

The third phase of a multi-stakeholder, integrated catchment management project at the Whatawhata Research Centre is described. Land use and management changes were implemented to improve economic and environmental performance of the Mangaotama case study catchment farm. The major changes included: afforestation of 160 of the 296 ha catchment farm with pine and native trees, riparian management of the entire 20 km of stream network via fencing and/or forestry, restoration of 5 ha of existing native forest, and intensification of the remaining pastoral component to a high fecundity ewe flock and bull beef finishing. Marked improvements were observed in the key environmental and economic performance indicators. In particular, declines in sediment (76%) and phosphorus (62%) loads and faecal coliform (43%) levels were observed, native forest fragments showed early signs of recovery in terms of sapling numbers and vegetative cover, and the pastoral enterprise recorded increased per hectare production of lamb (87%) and beef (170%). There were implementation challenges with the better matching of land use to land capability, but this study demonstrated that significant progress can be made in the short-term.

Integrated catchment management effects on flow, habitat, instream vegetation and macroinvertebrates in Waikato, New Zealand, hill‐country streams

“…average suspended sediment load at site RM during 2001-05 was 76% lower than before the iCM changes (Dodd et al 2008c) and our a priori prediction was that reduced input of fine sediment to streams after iCM changes would reduce SiS amount and % fine sediment cover of the streambed and increase the organic content of periphyton (reflecting lower fine inorganic sediment content) within the timescale of this study. Three of the four iCM sites showed the predicted increases in periphyton organic content, although only site RS showed a trend of declining % fines cover (from an initial high level).…”

“…The rapid reduction in stream temperatures and progress towards restoration of invertebrate community composition Quinn et al-Stream response to integrated catchment management and metrics, together with reduced landslip erosion in pine afforested areas after 5 years (Quinn & Basher 2007) and lower nutrient and sediment loads (Dodd et al 2008c), show that the iCM plan has reduced key aquatic environmental stressors and had significant ecological benefits. Afforestation also has wider environmental benefits for climate change management through greenhouse gas sequestration (houghton 2003).…”

“…initial analyses indicate that the Mangaotama iCM plan has enhanced long-term economic performance, reduced stream temperature, reduced export of sediment and phosphorus, improved water clarity, and resulted in a more pollution-sensitive invertebrate community as indicated by trends in the Macroinvertebrate Community Index (MCI) (Quinn et al 2007a;Dodd et al 2008c). This study examined the response in more detail, emphasising stream flow, water temperature, geomorphology (channel and water width and water depth), habitat 778 New Zealand Journal of Marine and Freshwater Research, 2009, Vol.…”

The interactive effects of livestock exclusion and mammalian pest control on the restoration of invertebrate communities in small forest remnants

“…Furthermore, we are aware of no studies that that have explicitly tested the effects of livestock exclusion on invertebrate communities in native forest remnants in New Zealand. even for plant communities, there have been remarkably few studies of the effects of livestock grazing in New Zealand forests Buxton et al 2001;Timmins 2002;miller 2006;Dodd et al 2008;Smale et al 2008) despite the severe damage caused by livestock in the forest understorey. of these, we know of only two previous studies that have measured the long-term recovery of plant communities following livestock exclusion from forest remnants (Smale et al 2005;Dodd & power 2007;but see also pettit et al 1995, Spooner et al 2002, close et al 2008 for short-term temporal studies of livestock exclusion from forest remnants in New Zealand and australia).…”

“…although there have been no previous attempts to test the potential conservation benefits of management intervention for the restoration of native invertebrate communities in severely degraded forest remnants, recent studies testing the effects of livestock exclusion on plant community dynamics and physical soil properties in forest remnants Smale et al 2005;Dodd & power 2007;Dodd et al 2008;Smale et al 2008) suggest that strong responses might also be expected among soil-and litter-dwelling invertebrates.…”