Global food demand is growing rapidly. Livestock grazing can provide a valuable source of protein, but conventional grazing is often unsustainable. We studied an 800,000-ha section of a threatened ecoregion in southeastern Australia. Conventional management in the region involves continuous livestock grazing with few rest periods and regular fertilizer application. By using remotely sensed data on tree cover and extensive field data on livestock grazing regimes, soil chemistry, tree diameters, and tree regeneration, we show that the region is facing a tree regeneration crisis. Under conventional management, across the region, millions of hectares of land currently supporting tens of millions of trees will be treeless within decades from now. This would have severe negative ramifications for biodiversity and key ecosystem services, including water infiltration and shade provision for livestock. However, we identified an unexpected win-win solution for tree regeneration and commercial grazing. A relatively new practice in the region is fast-rotational grazing, characterized by prolonged rest periods in between short, intensive grazing events. The probability of regeneration under fast-rotational grazing was up to 4-fold higher than under conventional grazing, and it did not differ significantly from the probability of regeneration in ungrazed areas. In addition, trees were more likely to regenerate where soil nutrient levels were low. These findings suggest that the tree regeneration crisis can be reversed by applying low-input, fastrotational grazing. New policy settings supporting these practices could signal a turning point for the region, from ecological decline to ecological recovery.countryside biogeography ͉ grassy box woodlands ͉ holistic management ͉ rotational grazing ͉ scattered trees

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Agriculture and livestock grazing threaten biodiversity around the world. In the grazing landscapes of eastern Australia, a common conservation strategy has been to exclude livestock from large patches of trees (typically > 5 ha). This has major local benefits, but is unlikely to stem regional biodiversity loss. Using a case study from the Upper Lachlan catchment in New South Wales, we show that (1) approximately 30% of tree cover occurs as very small patches or scattered trees; (2) large patches have disappeared from 90% of the landscape; and (3) large patches are 3.5 times more likely to be in unproductive upland areas than in lowland areas of high conservation concern. Given the limitations of focusing on large patches of trees to achieve regional conservation outcomes, the next generation of conservation initiatives should consider a new suite of additional measures that could deliver biodiversity benefits across broad areas of the region. Two key measures that must be considered are new incentives for farmers to alter livestock grazing practices and reduce fertilizer use.

Object The pathophysiology of tethered cord syndrome (TCS) is uncertain; however, it has been suggested that fibrous and fatty elements within the filum terminale (FT) play a role. The objective of this study was to describe the radiological and histological features of the FT in TCS and determine if there are associations between those features and clinical outcomes, complications, and urodynamics. Methods In this retrospective study, histological, MRI, and clinical data obtained in 293 patients with TCS who underwent FT transection were reviewed and analyzed in a multivariate analysis. Results The median patient age was 4.9 years (range 0.3–64.3 years). On MRI, a fatty filum was present in 65% of patients and a thickened filum (> 2 mm) was seen in 45%. Histologically, the FT contained prominent fibrous tissue in 95%, nerve twigs in 79%, adipose tissue in 59%, and vascular tissue in 36%. Histological features associated with a thickened filum on MR images were adipose tissue (OR 3.5, p < 0.001), nerve twigs (OR 2.2, p = 0.028), and vascular tissue (OR 0.5, p = 0.025). Adipose tissue was associated with a conus level below the L2–3 disc space (OR 2.3, p = 0.031) and with a fatty filum on imaging (OR 9.8, p < 0.001). Nerve twigs were associated with abnormal urodynamics (OR 10.9, p = 0.049). The only variable predictive of clinical improvement was conus level; patients with conus levels caudal to L-2 were less likely to improve postoperatively (OR 0.3, p = 0.042). Conclusions Fibrous tissue was ubiquitous and may be important in the pathophysiology of TCS. Nerve twigs and adipose tissue were associated with abnormal urodynamics and low-lying coni, respectively. Although the majority of patients clinically improved, patients with normal conus levels had significantly better outcomes.

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