Earthworms as indicators of sustainable production in dryland cropping in southern Australia

摘要: Abstract Crop-monitoring by farmer groups has been established to identify agronomic and soil factors limiting crop yields promote the adoption of sustainable farming practices in South Australia. The use earthworms as a potential indicator sustainability investigated with survey 95 paddocks sown wheat, barley or peas, within an area about 3500 km 2 . Mean annual rainfall ranged from less than 350 mm more 500 mm, soils varied coarse sands through lighter loams heavy clays. dryland cropping Australia have colonized four immigrant earthworm species, Aporrectodea rosea (Savigny), trapezoides (Duges), Microscolex dubius (Fletcher) phosphoreus (Duges); populations are generally dominated A. Population differences, such higher numbers recorded under peas juveniles occasional abundance other species some may be used indicate changes conditions associated management. Conservation tillage, retaining plant-residues reducing cultivation, is being promoted desirable developing systems inverse relationship between intensity tillage (r = −0.69 ∗∗∗ ) provides support for sustainability. Earthworm showed small but significant correlation activity grain 0.44 protein content 0.52 ). A positive nitrogen fertilizer levels 0.48 biomass 0.43 related increased organic matter, derived plant growth. distribution dependent not only on management production, also local climatic factors. Density were significantly inversely correlated sand. soils, crops, climate, history region geographic scale surveyed here probably too diverse provide simple relationships productivity. It important distinguish broad concept productivity regional basis reality spatial temporal scales organisms studied production processes involved. At appropriate scale, ecological data both composition functional communities, useful indicators its