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Background: Grasslands in drylands are increasingly influenced by human activities and climate change, leading to alterations in albedo and radiative energy balance among others. Surface biophysical properties and their interactions change greatly following disturbances. However, our understanding of these processes and their climatic impacts remains limited. In this study, we used multi-year observations from satellites and eddy-covariance towers to investigate the response of albedo to variables closely associated with human disturbances, including vegetation greenness (EVI) and surface soil volumetric water content (VWC), as well as snow cover and clearness index (Ta) for their potential relationships. Results: EVI and VWC during the growing season were the primary factors influencing albedo. EVI and VWC were negatively correlated with albedo, with VWC's total direct and indirect impacts being slightly smaller than those of EVI. During the non-growing season, snow cover was the most influential factor on albedo. VWC and Ta negatively affected albedo throughout the year. We estimated the impact of variations in EVI and VWC on climate to be in the range of 0.004 to 0.113 kg CO2 m−2 yr−1 in CO2 equivalent. Conclusions: This study indicates the significant impacts of climate change and human disturbances on vulnerable grassland ecosystems from the perspective of altered albedo. Changes in vegetation greenness and soil properties induced by climate change and human activities may have a substantial impact on albedo, which in turn feedback on climate change, indicating that future climate policies should take this factor into consideration. [ABSTRACT FROM AUTHOR]

To examine the dual environmental effects of emission control areas (ECAs) and reduced speed zones (RSZs), this study formulates an integrated container ship operation optimization model based on the fundamental facet of liner-service market. Capturing the critical characteristics of container ship operation, the proposed model explicitly incorporates the entire voyage that consists of container ship sailing and port activities as well as nonproductive stay in port. Compared to the separate establishment of ECAs, joint regulations of ECAs and RSZs can lead to more SO x emission reduction within it and less profit loss of the container ship by means of differentiated operation. Meanwhile, the optimal operation speed inside ECAs and RSZs of profit maximization is 10.638 knots, applied to the case study of CSCL Pacific Ocean, the container ship sailing MEX route from Far East (Shanghai, China) to Persian Gulf (Dammam, Saudi Arabia). These findings can provide insights for liner operators in carrying out differentiated operation from the demand side, as well as environmental regulators in adjusting emission reduction regulations dynamically. Image 1 • Global shipping emission has been rising steadily in recent years. • Resorting to reduced speed zones solely does not cut down total emission. • Establishing of emission control areas separately leads to more profit loss. • Implementing jointly realizes total emission reduction and less profit loss through differentiated operation. [ABSTRACT FROM AUTHOR]