Visual evaluation of soil structure (VESS) is spreading worldwide as a low-cost and efficient tool, helping farmers, consultants and researchers to assess soil quality changes. Biological indicators, as macrofauna, play an important role affecting soil health, and its relationship with soil structure brings valuable information about how to improve land use and management. The relationships between VESS and biological indicators are still scarce in soil science, making our findings very important to stimulate further research on the topic.

Portable X-ray fluorescence (pXRF) spectrometry is increasingly applied for assessing total elemental contents of soils and other matrices. This study compared the elemental correspondence between pXRF data under different sample preparation conditions with the traditional acid-digestion-based (USEPA 3051a) method, justified by very rare studies with tropical soils. pXRF decreases the time for determination of Ca, Cu, Fe, Mn, Cr, Ni, Al, Zn, Ti and V and can be an alternative to acid-digestion-based methods, reducing cost and generation of chemical wastes.

Soil structure controls soil physico-chemical properties, biogeochemical cycling and ultimately plant productivity. We evaluated soil aggregates under potato (Solanum tuberosum L.), fallow and Eucalyptus globulus L. land uses in the central Andes, Bolivia. Microbial biomass and oxy-hydroxides were the main soil constituents related to aggregate size distribution and stability. Eucalyptus improved soil structure, while fallowing did not induce soil structural changes compared to cultivated fields. Alternative management practises are required to maintain soil structure and optimising sustainable land use of cultivated and fallow fields.

Optimising fertiliser N types may have the potential for mitigating NO and N₂O emissions from vegetable fields. Annual N₂O and NO fluxes were simultaneously taken from a typical greenhouse vegetable field under four N fertiliser treatments, including no N fertiliser (control), only chemical N fertiliser, only organic N fertiliser, and organic–chemical mixed fertiliser. Our study contributes to better optimise nitrogen fertiliser management for improving vegetable production while mitigating greenhouse gas emissions.

Silvopastoral systems (SSPs) have been used in tropical climates to improve agricultural production and environmental indicators. Tree density and system age are factors influencing soil carbon stock (SCS) and our results suggest that SSP can sequestrate more soil carbon than native vegetation and that older systems have higher SCS, probably due to greater carbon cycling in the particulate fraction. These results show that the SSP use, especially older ones, can increase SCS and improve sustainability in tropical climate regions.

Predicting large-scale hydrological processes in terrestrial ecosystems requires an understanding of soil water and solute dynamics and plant-extraction of water. This glasshouse study used the transpiration rate of maize plants to evaluate the efficacy of a previously published model for predicting the soil water content and its salt concentration. The model was validated for early stages of plant growth but significant deviations occurred as plants grew larger, water contents declined, and salt concentrations increased. Better estimates of daily changes in these parameters would make the model more useful.

Phosphorus fertilisers, in particular chemical P fertilisers, were excessively applied to achieve high yields for meeting the ever-growing demands in cultivation, leading to poor quality, fertiliser waste and water eutrophication. We found a new wood rot-fungus Fomitopsis palustris CQ2018 that could mobilise soil P and improve plant P uptake, fruit yield and quality in cultivation. It may be potentially developed as a new, effective, cheap and environmentally friendly biofertiliser, which may reduce the need for chemical P fertiliser.

We present a method to assess management effects on soil carbon storage across a commercial field, where replicating a field trial is not often feasible. The method uses data that consist of large numbers of correlated point values from unreplicated, side-by-side field trials. The method provides the opportunity to analyse whole-field data and to improve our understanding of soil C processes at commercial fields.