Changes in atmospheric aerosols have profound effects on ecosystem productivity, vegetation growth and activity by directly and indirectly influencing climate and environment conditions. However, few studies have focused on the effects of atmospheric aerosols on vegetation growth and activity in the vulnerable arid and semi-arid regions, which are also the source areas of aerosols. Using the datasets of aerosol optical depth (AOD), normalized difference vegetation index (NDVI) and multiple climatic variables including photosynthetically active radiation (PAR), surface solar radiation (SSR), surface air temperature (TEM) and total precipitation (PRE), we analyzed the potential responses of vegetation activity to atmospheric aerosols and their associated climatic factors in arid and semi-arid regions of Asia from 2005 to 2015. Our results suggested that areas with decreasing growing-season NDVI were mainly observed in regions with relatively sparse vegetation coverage, while AOD tended to increase as NDVI decreased in these regions. Upon further analysis, we found that aerosols might exert a negative influence on vegetation activity by reducing SSR, PAR and TEM, as well as suppressing PRE in most arid and semi-arid regions of Asia. Moreover, the responses of atmospheric aerosols on vegetation activity varied among different growing stages. At the early growing stage, higher concentration of aerosol was accompanied with suppressed vegetation growth by enhancing cooling effects and reducing SSR and PAR. At the middle growing stage, aerosols tended to alter microphysical properties of clouds with suppressed PRE, thereby restricting vegetation growth. At the late growing stage, aerosols exerted significantly positive influences on vegetation activity by increasing SSR, PAR and TEM in regions with high anthropogenic aerosols. Overall, at different growing stages, aerosols could influence vegetation activity by changing different climatic factors including SSR, PAR, TEM and PRE in arid and semi-arid regions of Asia. This study not only clarifies the impacts of aerosols on vegetation activity in source areas, but also explains the roles of aerosols in climate.

大气气溶胶的变化通过直接和间接影响气候和环境条件对生态系统生产力、植被生长和活动产生深远影响。然而，很少有研究关注大气气溶胶对脆弱干旱和半干旱地区植被生长和活动的影响，这些地区也是气溶胶的来源区。利用气溶胶光学深度 (AOD)、归一化植被指数 (NDVI) 和包括光合有效辐射 (PAR)、地表太阳辐射 (SSR)、地表气温 (TEM) 和总降水量 (PRE) 在内的多个气候变量数据集，我们分析了 2005 年至 2015 年亚洲干旱和半干旱地区植被活动对大气气溶胶及其相关气候因素的潜在响应。我们的研究结果表明，生长季 NDVI 减少的区域主要出现在植被覆盖相对稀疏的区域，而 AOD 则随着这些区域 NDVI 的减少而增加。经过进一步分析，我们发现气溶胶可能通过降低 SSR、PAR 和 TEM 以及抑制亚洲大部分干旱和半干旱地区的 PRE 对植被活动产生负面影响。此外，大气气溶胶对植被活动的响应因生长阶段而异。在生长早期，较高浓度的气溶胶伴随着通过增强冷却效果和降低 SSR 和 PAR 抑制植被生长。在生长中期，气溶胶倾向于改变云的微物理特性，抑制 PRE，从而限制植被生长。在生长后期，在人为气溶胶高的地区，气溶胶通过增加 SSR、PAR 和 TEM 对植被活动产生显着的积极影响。总体而言，在不同的生长阶段，气溶胶可以通过改变亚洲干旱和半干旱地区的 SSR、PAR、TEM 和 PRE 等不同气候因素来影响植被活动。本研究不仅阐明了气溶胶对源区植被活动的影响，而且解释了气溶胶在气候中的作用。亚洲干旱和半干旱地区的 TEM 和 PRE。本研究不仅阐明了气溶胶对源区植被活动的影响，而且解释了气溶胶在气候中的作用。亚洲干旱和半干旱地区的 TEM 和 PRE。本研究不仅阐明了气溶胶对源区植被活动的影响，而且解释了气溶胶在气候中的作用。