To better understand the variation properties of marine aerosol during transport, single particle aerosol mass spectrometer (SPAMS) was applied for the first time during a comprehensive ocean experiment over the South Yellow Sea in November 2012. Two parallel sections influenced by marine air masses with constant wind direction from ocean to land (Section 1), and continental air masses with constant wind direction from land to ocean (Section 2), respectively, were selected to study the variation of chemical characteristics of marine aerosol. The results showed that the average particle count in Section 2 was around 3.5 times higher than that in Section 1, which might be ascribed to the influence of continental air masses, accompanied with high wind speed in Section 2. Particle counts of major components (SO₄^2-, NO₃^-, NH₄⁺, OC and EC) containing particles in Section 1 and Section 2 (excluding NO₃^-) gradually decreased by 58%-74% and 34%-53%, and the reductions in Section 1 were greater than that in Section 2. Secondary aerosol contributed to the highest fraction (42%) of the total particles in Section 2, while sea-salt aerosol contributed to the highest (>30%) in Section 1. The contribution of secondary and other anthropogenic aerosols (including biomass burning, Soot-like and Pb-containing aerosols) in both sections were significant. It indicated that the contribution of anthropogenic air pollutants to marine aerosol could not be ignored over the South Yellow Sea.

The authors conducted experiments to simulate warming and alter precipitation since 2011, and investigated soil physical properties (soil particle size and pH) and carbon pools (soil total carbon (STC), soil organic carbon (SOC), soil extractable organic carbon (EOC) and microbial biomass carbon (MBC)) in July 2013. The results showed that warming significantly increased soil temperature and decreased soil moisture at the depths of 0-20 cm, and altered precipitation affected soil moisture at 0-20 cm depth, but had no influence on soil temperature. At the depth of 0-10 cm, warming significantly increased SMBC; increased precipitation significantly reduced EOC content and elevated MBC content; decreased precipitation significantly decreased soil sandy proportion, MBC content and increased soil clay proportion and EOC content. At the depth of 10-20 cm, increased precipitation led a reduction on EOC content. The interactions of warming and altered precipitation on soil indexes were not detected. The pattern of soil properties was changed mainly by altered precipitation, not warming, according to the results of PCA. The results suggest that given precipitation will be continuously increased in the future, increased precipitation may lead a reduction in soil clay proportion and EOC content in the topsoil, and subsequently affect plant primary production and micrbial communities in this region.

To investigate species’ resource competition strategies with traits of the leaf economics spectrum across contrasting environments and to examine the effects of nutrient additions on the ranking of species based on their leaf economics spectrum in an alpine grassland on the Qinghai-Tibetan Plateau, five leaf traits (LDMC: leaf dry matter content, SLA: specific leaf area, LC: leaf carbon concentration, LN: leaf nitrogen concentration and LP: leaf phosphorus concentration) were measured for 10 plant common species in all plots. The results showed that N addition significantly increased LN by 9.4% and P addition significantly increased LP by 81.8%. There were significant interactions between N addition and P addition on SLA and LDMC, which increased SLA by 15.3% and decreased LDMC by 10.1%. In addition, there were species-specific responses of leaf traits across multivariate trait space to nutrient additions. The variation in species responses to NP addition significantly changed the species ranking based on the leaf economics spectrum. These results showed that co-occurring species followed a conservative strategy in the infertile environment and an exploitative strategy in the fertilized ones by increasing SLA and leaf nitrogen and phosphorus concentrations. Different species responses to NP addition caused a new species distribution based on the leaf economics spectrum. These results suggest that, before using leaf traits to predict responses of community structure and ecosystem functioning to nitrogen and phosphorus additions, it is necessary to take the species-specific responses into consideration.