Fjölrit RALA - 05.12.1999, Page 133

Kevin F. O’Connor etal.
131
employed to prevent soil erosion as well as to improve livestock shelter and local tim-
ber supplies. The implications of such revegetation to nutrient balances also warrant
attention.
QUANTIFYING CARBON AND NUTRIENT POOLS IN SOILS AND BIOMASS
Identification of representative sites and data sources
Reliable data for nutrients in biomass and soil under forest in the high country are at
present available only for the Craigiebum Mountains. Several general locations have
been identified for which we have substantial collections of comparable data for tall
tussock grassland biomass, nutrient concentrations in phytomass, especially above-
ground. For many of these we now have data on carbon and nutrient levels in soils,
although these are not all complete data sets, nor are soil data or plant nutrient con-
centration data always derived from the same site as the biomass data.
For the four general locations selected for presentation here, altitude and climate
zones are specified for each locality (a, b, c, etc.,) because in some cases, degradation
sequences are being studied at more than one altitude. To identify valid examples of
stages in such a sequence depends on holding constant other environmental factors.
The influence of pastoral animal behaviour on the incidence of vegetation change that
has been earlier emphasised, makes it possible to identify examples where there is
minimal variation in other factors. Field examples of different stages of a degradation
sequence or cultural development sequence are available for some other localities, but
many have not yet been sampled adequately and some are not represented with fully
processed data.
Location 1. Craigiebum Mountains, Puketeraki Ecological Region, Canterbury
1 a. Humid, penalpine, Spenser soil, Chionochloa pallens grassland.
lb. Humid, subalpine, Tekoa soil, (i) Nothofagus solandri var. cliffortioides for-
est, (ii) C. macra grassland, (iii) induced Festuca-Agrostis-Hieracium grass-
land; (iv) planted Pinus contorta afforestation harvested after 13 years.
lc. Humid, montane, Cass soil, C. rubra grassland.
Data sources: Mountain beech forest biomass, nutrients and soils; Kelland
1978, Nordmeyer 1980a, 1980b. Grassland biomass, nutrients and soils;
Kelland 1978, Evans 1980, this paper. Pine forest biomass, nutrients and
soils; Nordmeyer 1980a, 1980b, this paper.
Location 2. Hakatere Basin, Heron Ecological Region, Canterbury
2a. Moist subhumid, subalpine, Puketeraki soil, C. macra grassland.
2b. Moist subhumid, montane, Tasman/Pukaki soils, (i) C. rigida grassland, (ii)
mixed Festuca-Chionochloa grassland, (iii) short, sparse Festuca-Hieracium
grassland, (iv) herbaceous revegetation with legumes, including Lupinus.
Data sources: Chionochloa biomass and nutrients; Williams 1977, Williams
et al. 1977a, 1977b. Soils and all other data; Davis 1991, this paper.
Location 3. Tekapo district, Mackenzie Ecological Region, South Canterbury
3. Dry subhumid, montane, Tekapo/Pukaki soils, (i) C. rubra grassland, (ii) de-
rived Festuca novae-zelandiae grassland, (iii) short, sparse Festuca-
Hieracium grassland.