Impact of climate variability on apple production and diversity in Kullu valley, Himachal Pradesh

Abstract

The study assessed the impact of climatic factors on productivity and biodiversity of apple in Kullu valley area. The secondary meteorological data was used to evaluate the impact of climate change on apple diversity with the help of correlation, trend analysis, step up regression and Utah model. The annual average maximum temperature of lower Kullu valley showed increase of 1.2°C in the period of 1985–2009. Winter temperature and summer temperature were found to be increasing at the rate of 0.09°C and 0.06°C per year, respectively. A decreasing trend of rainfall was observed during the winter months. The productivity of apple crop during 1985–2009 showed a cyclic pattern with an overall decreasing trend of 0.4 tonnes/ha. The productivity sensitivity analysis with maximum temperature showed a negative rate of 3.89 every year. Regression analysis revealed that minimum temperature of January, February and November, rainfall of December, and maximum temperature for March and October were important factors to predict the apple yield. The farmers’ perception revealed adverse effects on apple biodiversity due to change in climatic conditions. The farmers reported that change in the snowfall pattern led to depletion and shifting of ecological niche of traditionally and commercially important apple varieties and an increase in low chill cultivars. Apple growers specifically in lower Kullu valley switched over to alternate crops and some preferred shifting their orchards to higher altitudes. Cumulative chill units showed a decrease of 9.52 in negative and 6.5 chill units every year in Positive chill units hours of Utah model in Kullu district due to increase in temperature.