Exploring the influence of density-dependence and weather on the spatial and temporal variation in common vole (Microtus arvalis) abundance in Castilla y León, NW Spain.

BACKGROUND: The common vole has invaded the agroecosystems of northwestern Spain, where outbreaks cause important crop damage and management costs. Little is yet known about the factors causing or modulating vole fluctuations. Here, we used 11 years of vole abundance monitoring data in 40 sites to study density-dependence and weather influence on vole dynamics. Our objective was to identify the population dynamics structure and determine whether there is direct or delayed density-dependence. An evaluation of climatic variables followed, to determine whether they influenced vole population peaks. RESULTS: First- and second-order outbreak dynamics were detected at 7 and 33 study sites, respectively, together with second-order variability in periodicity (2-3 to 4-5-year cycles). Vole population growth was explained by previous year abundance (mainly numbers in summer and spring) at 21 of the sites (52.5%), by weather variables at 11 sites (27.5%; precipitation or temperature in six and five sites, respectively), and by a combination of previous abundance and weather variables in eight sites (20%). CONCLUSIONS: We detected variability in vole spatiotemporal abundance dynamics, which differs in cyclicity and period. We also found regional variation in the relative importance of previous abundances and weather as factors modulating vole fluctuations. Most vole populations were cyclical, with variable periodicity across the region. Our study is a first step towards the development of predictive modeling, by disclosing relevant factors that might trigger vole outbreaks. It improves decision-making processes within integrated management dealing with mitigation of the agricultural impacts caused by voles. © 2023 Society of Chemical Industry.

Classification of airborne multispectral imagery to quantify common vole impacts on an agricultural field.

BACKGROUND: The common vole (Microtus arvalis) is a very destructive agricultural pest. Particularly in Europe, its monitoring is essential not only for adequate management and outbreak forecasting, but also for accurately determining the vole's impact on affected fields. In this study, several alternatives for estimating the damage to alfalfa fields by voles through unmanned vehicle systems (UASs) and multispectral cameras are presented. Currently, both the farmers and agencies involved in the integrated pest management (IPM) programs of voles do not have sufficiently precise methods for accurate assessments of the real impact to crops. RESULTS: Overall, the four multispectral classification methods presented showed similar performances. However, the normalized difference vegetation index (NDVI)-based segmentation exhibited the most accurate and reliable appraisal of the affected areas. Nevertheless, it must be noted that the simplest method, which was based on an automatic classification, provided results similar to those obtained by more complex methods. In addition, a significant direct relationship was found between the number of active burrows and damage to the alfalfa canopy. CONCLUSION: Unmanned vehicle systems, combined with multispectral imagery classification, are an effective and easily transferable methodology for the assessment and monitoring of common vole damage to agricultural plots. This combination of methods facilitates decision-making processes for IPM control strategies against this pest. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Quality evaluation of sour and duke cherries cultivated in south-west Europe.

BACKGROUND: The results of many studies describing sour cherry polyphenols and their positive effects on human health have been reported. However, there are no detailed studies concerning the physical quality of fresh fruits of sour and duke cherry. RESULTS: Several physical, chemical and colour fruit-characteristics of 10 sour and duke cherry cultivars cultivated for industrial use in south-west Europe were investigated during a 3-year (2008-2010) period. Some of the cultivars showed distinctive and interesting agronomical characters, such as low susceptibility to fruit cracking and high soluble solids and total polyphenol levels. This was the case with the duke cherry cultivar Guindo Garrafal Negro. Its fruits were quite sweet (18.49°Brix), resistant to cracking (6.34%) and rich in polyphenols (17.16 g gallic acid kg(-1) dry weight). Other relevant cherry cultivars were Guindo Tomatillo and Seixas, which had large and fleshy fruits (4.71 and 3.69 cm(3), respectively) and Guindo Silvestre, for which the lowest fruit cracking values (3.12%) were recorded. CONCLUSIONS: Sour and duke cherries are rich in healthy compounds such as polyphenols. Studies including the physical, chemical and colour properties of sour and duke cherry fruits are very interesting to engineers in the design of equipment for harvesting and post-harvest technology.