Estimating Pasture Land Cover in the New England Region of Northern New South Wales

Land cover across the southern Australian temperate agricultural region comprises primarily of native pasture, introduced improved pastures and crops for livestock production and also perennial remnant vegetation. A feed-base pasture audit was carried out throughout southern Australia commencing mid-year 2011 (Donald and Burge 2012; Donald et al. 2012). The purpose of the audit was to map and analyse information obtained about the pasture feed-base for livestock production by surveying Statistical Local Areas (SLAs) across the southern states. The purpose of this Feed-Base audit was to survey pastures within agricultural NSW, Victoria, Tasmania, South Australia and South-Western Australia, collate these data into an organised database, and prepare a short report and summarise by tabulating and mapping pasture species abundance and distribution. Data collected were based on “desk-top estimates” by state district agronomists and agricultural consultants. In this paper a method using satellite imagery is described on how more objective assessments of pasture types can be provided as a means to discriminate between the SLA’s major pasture classes far more objectively than by visual assessment. Satellite remote sensing may be used to define landcover classes for large regional areas. A number of procedures have been developed to discriminate between pastures, crop and woody vegetation (for example Hill et al. 1997, Emelyanova et al. 2008). In the Hill study (Hill et al. 1997) NOAA AVHRR NDVI provided spatial land cover maps of pasture cover at 1 km resolution. The classifications results in that study showed that satellite information may be used to help in the interpretation of pasture survey results, and in turn, the survey data can provide some validation data for the pasture types ascribed to the remotely sensed classes. In this study daily temporal continental scale imagery from 250 m2 resolution TERRA and AQUA satellite Moderate Resolution Imaging Spectroradiometer (MODIS) normalised difference vegetation index (NDVI) composited into weekly continental images provided a means to assess temporal profile of spectral greenness over the growing season

Domestication of the Annual Legume \u3cem\u3eTrigonella balansae\u3c/em\u3e for Mixed Farming Systems in Southern Australia

An accession of the annual legume Trigonella balansae Boiss. and Reuter. has been selected for commercial release in Australia. The annual legume has significant potential as a self-regenerating pasture within mixed farming systems. As part of a duty-of-care assessment, we tested the hypothesis that sheep grazing the trigonella cultivar will have similar liveweight, condition scores, health and wool production to sheep grazing two widely adopted annual legumes, subterranean clover (Trifolium subterraneum L. cv Dalkeith) and French serradella (Ornithopus sativus Brot. cv. Erica). Forage dry matter digestibility (DMD), crude protein (CP), fibre, mineral content and isoflavones were measured across the plant’s lifecycle. The data supported the hypotheses and there were no significant differences in liveweight, wool growth, wool yield or condition score that were associated with pasture species. The mineral content of trigonella requires further investigation

Improving the Feeding Value of Dryland Lucerne in Australia

Lucerne (Medicago sativa L.) is the most widely grown perennial legume species in southern Australia. Within Australian farming systems it plays an important role in the provision of high-quality feed for livestock, nitrogen fixation and dewatering soils to reduce watertable recharge and dryland salinity (Cocks 2001). The majority of lucerne varieties have been developed for the areas with high rainfall or supplementary irrigation. The new challenge is to develop lucerne cultivars specifically for dryland mixed farming systems in temperate and mediterranean climate zones (Humphries and Auricht, 2001). Persistence in these environments and feeding value to sheep are critical selection traits. In this paper we compare nutritive traits of 35 commercial and experimental accessions of lucerne, sampled during the vegetative phase, and test the hypothesis that there will be significant differences between the accessions for in vitro dry matter digestibility (DMD), crude protein (CP), acid detergent fibre (ADF), neutral detergent fibre (NDF) and hemicellulose