Variable-load unmanned aerial vehicles (UAVs) are key tools in smart agriculture, particularly playing a vital role in the prevention and control of crop pests and diseases. Equipped with pesticide spraying equipment, these quadrotor UAVs offer advantages such as high operating speed, low risk of chemical drift, and improved crop coverage, making them widely used in agricultural plant protection. However, during spraying operations, the pesticide liquid gradually diminishes over time, leading to continuous changes in the UAV's overall mass, center of gravity position, and moment of inertia.

Soil acidification is one of the pressing issues confronting global farmland today. Studies indicate that approximately 40% of farmland soils worldwide are at risk of acidification. In China, the topsoil pH of major croplands has decreased by an average of 0.5 units between 1980 and 2000, largely attributed to excessive chemical fertilizer application and atmospheric acid deposition.

Tomato is an economically important horticultural crop widely cultivated globally, rich in nutrients such as lycopene and vitamin C. It can grow both in open-field systems and controlled environments like greenhouses. However, tomatoes exhibit asynchronous maturation, with fruits at various ripeness stages often coexisting on a single plant. Additionally, tomatoes have a relatively short postharvest shelf life. Precise and timely ripeness assessment is crucial for minimizing postharvest losses and maintaining product quality throughout the supply chain.

With the large-scale development of the livestock industry, a substantial amount of high-concentration organic wastewater is generated. Pollutants such as residual antibiotics, pharmaceutical ingredients, and heavy metals in the wastewater pose a serious threat to the safety of the water environment.

As the global population continues to grow and climate change intensifies, agricultural systems are facing unprecedented challenges. To meet food demand, agriculture has long relied on chemical fertilizers and pesticides, but these chemicals not only pollute the environment but also pose potential risks to human health. Meanwhile, crop diseases, particularly those caused by fungi, result in 20%–40% of global yield losses annually, with mycotoxin contamination posing a significant threat to food security.

In recent decades, global agriculture has accelerated specialization and intensification in pursuit of economies of scale, and China is no exception. Driven by the reform and opening-up policies, agricultural production efficiency has improved, but it has also come at an environmental cost: excessive use of chemical fertilizers, low utilization rate of livestock and poultry manure, leading to water eutrophication, air pollution and other issues.

Water is an essential resource for life, yet we rarely think about its origin or the processes that shape its quality. In the Santa Rosa canton, located in El Oro Province, the Santa Rosa River is the main source of water supply for 85% of the population, making it a strategic resource for the region’s social and economic development. However, this area is also characterized by intense mining activity, along with agriculture and urban growth, raising concerns about the condition of its water resources.

Phosphorus is essential for plant growth, yet much of the phosphorus in soils worldwide remains locked in forms that crops cannot use. A new review study highlights how biochar, a carbon-rich material derived from biomass, could play a key role in improving phosphorus availability and boosting agricultural sustainability.

A new commentary analyzes China’s shifting land-use policies, weighing ecological restoration via Grain for Green against food security pressures that have spurred forest-to-farmland conversion.