Bioclimatic analysis in a region of southern Italy (Calabria)

In this study, an analysis of precipitation and temperature data has been performed over 67 series observed in a region of southern Italy (Calabria). At first, to detect possible trends in the time series, an analysis was performed with the Mann–Kendall non-parametric test applied at monthly and seasonal scale. An additional investigation, useful for checking the climate change effects on vegetation, has also been included analysing bioclimatic indicators. In particular, Emberger, Rivas-Martinez and De Martonne indices were calculated by using monthly temperature and precipitation data in the period 1916–2010. The spatial pattern of the indices has been evaluated and, in order to link the vegetation and the indices,different indices maps have been intersected with the land cover data, given by the Corine Land Cover map. Moreover, the temporal evolution of the indices and of the vegetation has been analysed. Results suggest that climate change may be responsible for the forest cover change, but, given also the good relationship between the various types of bioclimate and forest formations, human activities must be considered

How spatial and temporal variability can effect fertilization trial results

The objectives of this paper were to study the influence of nitrogen fertilization on crop production using a linear mixed effects model with a first order continuous autoregressive correlation structure. On a 2-ha field, the most relevant soil properties were determined. Four fertilizer treatments were applied in a completely randomised block design with four replications (blocks) and repeated crop measurements were made in three crop seasons. The most relevant sources of variation in wheat production might not be ascribed to management of soil fertilization but to soil intrinsic variation and between-season variability. More advanced methods of statistical analysis need to be used to separate the residual error from error sources