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For plant populations to persist, seedling recruitment is essential, requiring seed germination, seedling survival and growth. Drought and grazing potentially reduce seedling recruitment via increased mortality and reduced growth. We studied these seed–related processes for two species indigenous to the Pamir Mountains of Xinjiang in northwestern China: Saussurea glacialis and Plantago lessingii. Seeds collected from Taxkorgan, Xinjiang, had a viability rate of 15.8% for S. glacialis but 100% for P. lessingii. Of the viable seeds, the highest germination rates were 62.9% for S. glacialis and 45.6% for P. lessingii. In a greenhouse experiment, we imposed a series of stressful conditions, involving a combination of simulated grazing and drought events. These had the most severe impact on younger seedlings. Modelling showed that 89% of S. glacialis mortality was due to early simulated grazing, whereas 80% of P. lessingii mortality was due to early simulated drought. Physiological differences could contribute to their differing resilience. S. glacialis may rely on water storage in leaves to survive drought events, but showed no shifts in biomass allocation that would improve grazing tolerance. P. lessingii appears more reliant on its root system to survive grazing, but the root reserves of younger plants could be insufficient to grow deeper in response to drought. After applying all mortality factors, 17.7 seedlings/parent of P. lessingii survived, while only

Land use and land cover (LULC) play a significant role in carbon regulation. South-China accounts for ~65% of China’s carbon sink. In Xishuangbanna (South-China), rubber is expanding rapidly creating an urgent need to understand and monitor LULC change and how spatial variation affects carbon storage (CS). This is vital for the formation and implementation of better land use management practices. We studied LULC changes of 22-year period; addressing how these changes have affected the CS. We quantified LULC changes between1988 and 2010 using remote sensing methods and calculated CS changes using InvEST. Results showed that between 1988 and 2010, the rate of deforestation accelerated to 203.2 km 2 y −1 and ~23% of forest were lost. Conversion of natural forest to rubber was responsible for 78% of this deforestation. Rubber expansion rate was 153.4 km 2 y −1 . Changes to LULC drove a temporal CS reduction 0.223 Tg C/km 2 . Local stakeholders have strong economic interest in converting land to more profitable plantations. Government efforts is required to control land conversion through new policies and incentives to retain natural forest. Assessment of specific potential land use change will be required to avoid promoting the conversion of high carbon storage land uses to low carbon storage land uses.

1 Despite three decades of intensive research on seed predation, rather little is known about how important a role it plays in plant demography. Here a balance sheet of seed predation is drawn up for Pinus sylvestris, based on mortality caused by its main seed predators. This species is of special interest because trees carry seeds throughout the year and can therefore support specialist as well as generalist seed predators. Also, its regeneration in Scotland is weak and some of its main seed predators (red squirrels, crossbills, wood ants) are themselves threatened. 2 Field data from two P. sylvestris forests were used to estimate rates of predation on seeds due to pre- and post-dispersal predators, including both specialists and generalists. The rates of predation changed systematically over time and were fitted to time-dependent functions. The resulting functions were incorporated into a model, which was solved numerically to determine the fate of a cohort of seeds. 3 On average, approximately 20% of seeds in the cohort were consumed by pre-dispersal seed predators, approximately 25% of seeds by post-dispersal seed predators, and approximately 55% of seeds were still alive at the end of 2 years. This reduces the seed pool for regeneration of P. sylvestris, but is unlikely to be a serious problem for regeneration. 4 Seed survival was most sensitive to the rate at which seeds became invulnerable to further seed predation, and to the rate of seed dispersal from cones on trees. Seed survival was less sensitive to seed predation. However, among seed predators, carabids feeding on loose seeds and birds eating seeds in open cones were the most important. 5 Cones open as they dry out, and the timing of seed dispersal is therefore weather-dependent. Late opening of cones had a deleterious effect on seed survival because it led to an increase in pre-dispersal seed predation. Thus, in a period of climate change, patterns of seed predation would be expected also to change, altering the success of regeneration.