[1] This study analyzes long-term climate and glacier records to examine climate change and glacier response over the past 45 years in Urumqi River source region, the Tianshan Mountains of China. The results show that summer temperature and annual precipitation near the glacier increased by 0.8°C and 87 mm (19%), respectively, during the study period. The glacier continuously retreated from 1962 to 2003, with the cumulated mass balance being À10,032 mm, or 20% of the glacier volume. Annual basin runoff has significantly increased by 413 mm or 62% during 1980 -2003 due to precipitation increase and enhanced glacier melt caused by summer climate warming. Both summer precipitation and temperate are negatively correlated with mass balance and positively associated with runoff. Relative to precipitationmass balance relation, the regression between temperature and mass balance is much stronger, indicating that summer temperature controls glacier mass balance and runoff changes. Citation: Ye, B

Studying the obstacles associated with continuous cropping is necessary for sustainable agricultural production. Phenolic acids play an important role in continuous cropping systems, although their mechanism of action in these systems remains unclear. Using High-performance Liquid Chromatography, we characterized the changes in phenolic acid contents in soils that had been continuously cropped with tobacco for different time periods and evaluated the interactions between soil physicochemical properties, bacterial community structure and diversity, and phenolic acids. Prolonged continuous cropping was associated with a significant increase in the content of phenolic acids and a significant decrease in soil pH and bacterial diversity. A significant negative correlation between pH and phenolic acids content was observed, suggesting that soil acidification potentially leads to the accumulation of phenolic acids. The Mantel test indicated that phenolic acids were positively associated with relative bacterial abundance ( R = 0.480, P < 0.01), signifying that the accumulation of phenolic acids is a potential factor leading to changes in bacterial community structure. Continuous cropping lowered the soil pH, which stimulated phenolic acid accumulation and consequently altered the bacterial community structure and diversity, ultimately impacting tobacco plant growth.

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Climate change is expected to have stronger effects on water resources in higher latitude regions. Despite intensive research on possible hydrological responses in those regions to a warmer environment, our knowledge on erosion and sediment yield induced by the climate change in high-latitude headwaters is still limited. In this study, we estimated suspended sediment yields from 2021 to 2050 in a typical headwater area of far Northeast China to elucidate potential impacts of future climate change on surface runoff and erosion in higher latitude regions. We first parameterized the Soil and Water Assessment Tool (SWAT) using historical measurements to estimate runoff from the river basin. The model performed well in both the calibration (2006)(2007)(2008)(2009)(2010)(2011) and the validation (2012-2014) periods, with an R 2 of 0.85 and 0.88 and a Nash-Sutcliffe Efficiency (NSE) of 0.7 and 0.73, respectively. We also utilized historical measurements on sediment yields from the period 2006-2014 to develop a runoff-sediment yield rating curve, and the rating curve obtained an excellent goodness of fit (R 2 = 0.91, p < 0.001). We then applied the calibrated SWAT model to two climate change projections, also known as Representative Concentration Pathways (RCP4.5 and RCP8.5), for the period from 2021 to 2050 to obtain future runoff estimates. These runoff estimates were then used to predict future sediment yield by using the developed runoff-sediment yield rating curve. Our study found a significant increase of annual sediment yield (p < 0.05) for both climate change projections (RCP4.5 = 237%; RCP8.5 = 133%) in this, China's high-latitude region. The increases of sediment yield were prevalent in summer and autumn, varying from 102-299% between the two RCPs scenarios. Precipitation was the dominated factor that determined the variation of runoff and sediment yield. A warming climate could bring more snowmelt-induced spring runoff and longer rainy days in autumn, hence leading to higher erosion. These findings demonstrate that under the changing climate, soils in this high-latitude headwater area would be eroded twice to three times that of the baseline period , indicating a potential risk to the downstream water quality and reservoir management.

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