Benefits of tropical peatland rewetting for subsidence reduction and forest regrowth: results from a large-scale restoration trial.

Drainage and deforestation of tropical peat swamp forests (PSF) in Southeast Asia cause carbon emissions and biodiversity loss of global concern. Restoration efforts to mitigate these impacts usually involve peatland rewetting by blocking canals. However, there have been no studies to date of the optimal rewetting approach that will reduce carbon emission whilst also promoting PSF regeneration. Here we present results of a large-scale restoration trial in Sumatra (Indonesia), monitored for 7.5 years. Water levels in a former plantation were raised over an area of 4800 ha by constructing 257 compacted peat dams in canals. We find peat surface subsidence rates in the rewetted restoration area and adjoining PSF to be halved where water tables were raised from ~ - 0.6 m to ~ - 0.3 m, demonstrating the success of rewetting in reducing carbon emission. A total of 57 native PSF tree species were found to spontaneously grow in the most rewetted conditions and in high densities, indicating that forest regrowth is underway. Based on our findings we propose that an effective PSF restoration strategy should follow stepwise rewetting to achieve substantial carbon emission reduction alongside unassisted regrowth of PSF, thereby enabling the peat, forest and canal vegetation to establish a new nature-based ecosystem balance.

Global LiDAR land elevation data reveal greatest sea-level rise vulnerability in the tropics.

Coastal flood risk assessments require accurate land elevation data. Those to date existed only for limited parts of the world, which has resulted in high uncertainty in projections of land area at risk of sea-level rise (SLR). Here we have applied the first global elevation model derived from satellite LiDAR data. We find that of the worldwide land area less than 2 m above mean sea level, that is most vulnerable to SLR, 649,000 km2 or 62% is in the tropics. Even assuming a low-end relative SLR of 1 m by 2100 and a stable lowland population number and distribution, the 2020 population of 267 million on such land would increase to at least 410 million of which 72% in the tropics and 59% in tropical Asia alone. We conclude that the burden of current coastal flood risk and future SLR falls disproportionally on tropical regions, especially in Asia.

Mitomycin C primary trabeculectomy in primary glaucoma of white patients.

PURPOSE: To evaluate the clinical outcome of eyes which underwent primary trabeculectomy with adjunctive mitomycin C (MMC) for primary glaucoma. PATIENTS AND METHODS: A prospective analysis of 25 eyes in 23 patients who underwent primary trabeculectomy with MMC for primary glaucoma was performed. Clinical outcome measures including postoperative intraocular pressure, change in logarithm of the minimum angle of resolution (LogMAR) visual acuity, and incidence of complications were measured up to 1 year postoperatively. RESULTS: Mean intraocular pressure decreased from 26.0 +/- 4.4 mmHg preoperatively to 12.5 +/- 3.9 mmHg (p < 0.0001) 1 year postoperatively. The mean LogMAR visual acuity changed from 0.23 +/- 0.19 preoperatively to 0.23 +/- 0.20 1 year postoperatively (p = 1.0). One eye developed a temporary hypotonous maculopathy and 4 eyes progressed in cataract formation. CONCLUSION: Primary trabeculectomy with MMC in eyes with primary glaucoma showed excellent pressure reduction. There were no cases of persistent hypotonous maculopathy or bleb endophthalmitis.

Graves' ophthalmopathy: what is the evidence for extraocular muscle specific autoantibodies.

Graves' ophthalmopathy is thought to be an autoimmune disease. Whether this disease is organ specific or one of the manifestations of the closely linked Graves' thyroid disease is still a matter of speculation. Many papers describe autoimmunity to orbital antigens, in particular to extraocular muscles, in patients with Graves' ophthalmopathy. In this paper we have tried to give an overview of the evidence for circulating antibodies against extraocular muscle antigens and to discuss their significance in relation to the immunopathogenesis of the disease.