Soil erosion affects land productivity, water quality, and ecosystem resilience. Traditional monitoring methods are often time-consuming, labor-intensive, and resource-demanding, while unmanned aerial vehicles (UAVs) provide high-resolution, near-real-time data, improving accuracy. This study conducts a bibliometric analysis of UAV-based soil erosion research to explore trends, technologies, and challenges. A systematic review of Web of Science and Scopus articles identified 473 relevant studies after filtering for terms that refer to types of soil erosion. Analysis using R’s bibliometrix package shows research is concentrated in Asia, Europe, and the Americas, with 304 publications following a surge. Multi-rotor UAVs with RGB sensors are the most common. Gully erosion is the most studied form of the issue, followed by landslides, rills, and interrill and piping erosion. Significant gaps remain in rill and interrill erosion research. The integration of UAVs with satellite data, laser surveys, and soil properties is limited but crucial. While challenges such as data accuracy and integration persist, UAVs offer cost-effective, near-real-time monitoring capabilities, enabling rapid responses to erosion changes. Future work should focus on multi-source data fusion to enhance conservation strategies.

Soil legacy data is past information on soils available from various sources (e.g. survey reports and maps). When compiled and organized, data obtained through historical retrieval can be used as basic input or validation data for digital soil mapping. A bibliometric analysis of this topic can reveal research patterns, evolution, and scientific contribution, thus mapping the science produced in a specific period and determining the trend in research topics based on search terms. This article presents the characterization of international scientific production on soil legacy data using a set of bibliometric indicators. The study was developed with the bibliometric analysis of scientific articles indexed in the Web of Science and Scopus data platforms regarding the use of soil legacy data published online from 1979 to 2022. The following were extracted from the articles: authors and co-authors, year and country of publication, index words used, and abstracts, which were submitted to bibliometric analysis in R. Bibliometric analysis revealed publication of 242 scientific articles in 117 journals involving 1223 authors throughout the world in the last 43 years, with an average frequency of 12.66 citations per article. Australia (10.33 %), the USA (8.68 %), and Brazil (7.85 %) were the countries with the greatest scientific contributions. The most cited studies refer to databases, demonstrating the ease of access to information contributes significantly to new local studies. Due to pedometrics importance for soil science, there is constant revision to available legacy data for new hypotheses and research in soil science. And also, for the monitoring of soil attributes for the conservation and preservation of natural resources.

The cover crops can reduce soil exposure and erosion while enhancing nutrient cycling for crops. Effective implementation requires understanding how cover crops decompose and release nutrients to align with crop demand. This research assessed the decomposition rates and nutrient release of various legume residues commonly used as green manure or cover crops in agricultural systems. The study took place in a nutrient-deficient Red-Yellow Ultisol, using a split-plot design with different legume cover crop species: Crotalaria juncea, Crotalaria spectabilis, Cajanus cajan, Cajanus cajan (L.) Millsp), Dolichos lablab, Canavalia ensiformis and Mucuna aterrima as the main plots and six evaluation periods: 0, 30, 60, 90, 120, and 150 days after incorporation (DAI) as the subplots. Initial mass losses were observed in the first 60 days, followed by a slower decline over the study period. The order of nutrient accumulation in biomass was found to be: K > N > P > Ca > Mg. The Dolichos lablab species had the slowest decomposition rate, with a half-life of 43 days, while Cajanus cajan had the fastest, with a half-life of 65 days. Potassium reached its maximum by 30 DAI, indicating a rapid transfer to the soil. Nitrogen, P, and K contents decreased during different vegetative phases, highlighting the importance of proper timing for legume management. Hemp, Crotalaria spectabilis, Dolichos lablab, and Canavalia ensiformis were suitable for short-cycle vegetables due to rapid nutrient availability. Conversely, Cajanus spp., and Mucuna aterrima were better for extended soil coverage and slow nutrient release.

Biofuels are central to decarbonising the transport sector but depend on achieving a life cycle carbon intensity (CI) lower than fossil equivalents. Land use change (LUC) is a complex and critical process for that, and its integration into policy frameworks is still debated. Brazil's 2018 National Biofuel policy, RenovaBio, aims at biofuels CI certification and decarbonisation. While it addresses LUC by risk-based eligibility criteria, critiques and opportunities for its improvement have emerged. This study reviews approaches to LUC in bioenergy policies and standards, discusses potential improvements in RenovaBio, and quantifies the potential impact of the inclusion of direct LUC (DLUC) on biofuels’ CI and on decarbonisation targets, focusing on ethanol and biodiesel from maize, soybean, and sugarcane. Four main LUC approaches could improve RenovaBio: DLUC quantification, LUC assessment of forest biomass, requiring certification for mandates and assessing ILUC risks. DLUC-CO2 after expansion over pastures can vary from -57 to +63 gCO2.MJ-1.yr-1 in high-yielding regions, which can both increase and decrease the biofuels’ CIs, depending on pastures’ vigour. There are enough eligible cropland and low-vigour pastures (3.2 to 7.4 Mha) to support feedstock production in volumes needed to meet policy targets. Quantifying DLUC could foster lower CIs and accelerate target achievement, adding 70 MtCO2 (+11%) savings in a minimum DLUC scenario. The results show opportunities to increase the consistency and completeness of the biofuels’ CI in RenovaBio, reward and incentivise best LUC practices, accelerate the achievement of decarbonization targets and reduce the risks of unsustainable and unintended effects.

Soil organic carbon plays a crucial role in soil fertility, water retention, and overall ecosystem health. Understanding the geomorphological characteristics of environments where soils with high organic carbon content occur is essential for sustainable land management and conservation efforts. In this context, the objective of this study was to characterize the geomorphology of environments where soils with high organic carbon content occur in southern Brazil. The study collected 135 soil samples to determine organic carbon content, soil classification, and geomorphological variables derived from the digital elevation model SRTM 30m. The investigation found that the environments where Organosols occur have higher altimetry values than the places where Cambisols predominate. The analysis also observed variations in the maximum values of slope between the environments of occurrence of the Organosols and Cambisols evaluated. The results demonstrate the potential of environmental variables related to geomorphology to characterize and identify environments that are more favorable to the occurrence of soils with high levels of organic carbon in southern Brazil, remotely and with reduced costs associated with collecting data in the field and in hard-to-reach areas.