Distinguishing Trajectories and Drivers of Vegetated Ecosystems in China's Loess Plateau

Terrestrial ecosystems can exhibit various behaviors in response to climate change and human activities. Nonlinear and abrupt shifts in ecosystems are particularly important as they indicate substantial modifications in ecosystem structure and function, posing a threat to the provision of ecosystem services. Here we distinguish between linear, curvilinear, and abrupt shifts in ecosystem productivity from 2000 to 2020 in China's Loess Plateau. We utilize spatial Random Forest models to analyze the driving factors behind these change patterns. Our findings indicate that 84.1% of the ecosystems experienced a positive change in plant productivity, while a small proportion (2.5%) exhibited a negative change. Abrupt shifts are prevalent in both positive and negative changes in ecosystem productivity, with negative changes often manifesting as abrupt shifts (79.3%). Negative changes in plant productivity, particularly the negative abrupt shifts, are primarily associated with human activities characterized by increased nighttime light and urbanization. Land conversion to forest is linked to a curvilinear trajectory in plant productivity, characterized by nonlinear changes with acceleration. Higher water availability and a wetter environment are more likely to promote positive changes in plant productivity. Moderate warming trends contribute to abrupt positive changes in plant productivity, while high warming trends are associated with increased negative abrupt and curvilinear changes. We highlight the importance of accounting for diverse change behaviors in ecosystems for the development of targeted conservation and restoration measures. Terrestrial vegetation provides numerous benefits to humans, including soil conservation, carbon sequestration, and regulation of water flows. Understanding how vegetation responds to climate change and human activities is crucial for developing targeted conservation and restoration measures. In China's Loess Plateau, we distinguish three types of change trajectories in ecosystem productivity from 2000 to 2020: linear, curvilinear, and abrupt shifts. We find that 84.1% of the ecosystems experienced positive changes in plant productivity, and only a small portion (2.5%) experienced negative changes. Interestingly, abrupt shifts occurred in both positive and negative changes in plant productivity. Human activities, land use conversions, and climatic factors collectively shape the diverse change trajectories in ecosystem productivity. These findings underscore the importance of considering different change behaviors in vegetation ecosystems when designing conservation and restoration strategies. Most areas of China's Loess Plateau (84.1%) experienced positive changes in plant productivity Abrupt shifts were common in positive and negative plant productivity changes Human activities, land use conversions, and climate collectively shape the diverse trajectories in plant productivity