Recent studies show advancing onset of plant growing season in many regions for the last several decades. With the well-established dependence of plant phenology on temperature, these trends are interpreted as an indication of global warming. For several decades, however, other determinants of plant phenology, e.g. varieties and trends in managed systems, may have changed and confounded the phenological trends. In this study, we tested if long-term changes in phenology of apple (Malus pumila var. domestica) are attributable to long-term changes in temperature by comparing the phenological response to long-term trend in air temperature, which is of our interest, with that to year-to-year fluctuation in air temperature, which should represent the real effect of temperature on phenology. We collected records of air temperature and phenological events (budding and flowering) in apple from 1977 to 2004 at six locations in Japan. Linear trends in flowering showed advancing rate in the range from 0.21 to 0.35 day yr À1 , statistically significant at three locations (Po0.05). We also found a warming trend in mean air temperature throughout March and April, with which flowering was closely correlated, in the range from 0.047 to 0.077 1C yr À1 , statistically significant at five locations (Po0.05). We separated the temperature time-series into two components: a long-term trend and a year-to-year fluctuation, by fitting smoothing spline to the trend and taking the residuals as the anomaly. We then fit a multiple regression model of phenological response to air temperature with separate coefficients for long-term trend and anomaly. Flowering date responded to the long-term trend at À3.8 day 1C À1 and to the anomaly at À4.6 day 1C À1 . The temperature coefficients were not statistically different from each other or among locations, suggesting that the advance of apple phenology has predominantly been caused by the temperature increase across the locations studied. The same result was also observed with budding.
The general consensus on future climate projections poses new and increased concerns about climate change and its impacts. Droughts are primarily worrying, since they contribute to altering the composition, distribution, and abundance of species. Grasslands, for example, are the primary source for grazing mammals and modifications in climate determine variation in the available yields for cattle. To support the agriculture sector, international organizations such as the Food and Agriculture Organization (FAO) of the United Nations are promoting the development of dedicated monitoring initiatives, with particular attention for undeveloped and disadvantaged countries. The temporal scale is very important in this context, where long time series of data are required to compute consistent analyses. In this research, we discuss the results regarding long-term grass biomass estimation in an extended African region. The results are obtained by means of a procedure that is mostly automatic and replicable in other contexts. Zambia has been identified as a significant test area due to its vulnerability to the adverse impacts of climate change as a result of its geographic location, socioeconomic stresses, and low adaptive capacity. In fact, analysis and estimations were performed over a long time window (21 years) to identify correlations with climate variables, such as precipitation, to clarify sensitivity to climate change and possible effects already in place. From the analysis, decline in both grass quality and quantity was not currently evident in the study area. However, pastures in the considered area were found to be vulnerable to changing climate and, in particular, to the water shortages accompanying drought periods.
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