Professor of Environmental Science
GB Pant University of Agriculture & Technology
Pantnagar – 263145 (Uttarakhand) India
When Satya Nand Stokes, an American missionary turned Hindu, imported Red Delicious variety of apple from the United States of America and introduced it in Indian Himalayas to give commercial impetus to apple production in India, no one might have imagined that apple industry would one day spell doom over Himalayan ecology. The exotic apple has not come alone, but has brought with it a set of technological tools and practices not compatible with the traditional food production systems operating in the Himalayas. Every ecosystem has its own unique characteristics— a unique physical environment, a unique community of plants, animals and microorganisms, a unique pattern of energy production and cyclic flow of nutrients. An ecosystem’s unique functioning is determined by its basic characteristics, especially its vegetation type and its composition. Introduction of an exotic species at a large scale alters ecosystem composition and phenomenally affects ecosystem functions. The exotic apple does do the same.
In the Kumaon region of Uttarakhand Himalayas, apple cultivation has covered an area of about 27000 ha. This area once was covered by oak (Quercus spp.) forests, which are the ecological climax forests in the middle and high Himalayas. Apples are grown successfully between an altitude range of 1600-2700 m above average sea level. This zone is also the oak zone. Thus, apple cultivation requires deforestation in the very beginning, to give place for the apple plants to grow. Banj (Quercus leucotrichophora), tilonj (Quercus floribunda) and kharsu (Quercus semicarpifolia) are the important species of oak in this zone. Rhododendron, kafal (Myrica esculenta) are the other associated species of this zone. The oak forests along with numerous other species have to be felled before planning an apple orchard in the mountains. Problems of water scarcity, soil erosion and environmental deterioration in the Himalayas are rooted in the destruction of natural oak forests, which are the climax forests. The last successional stage of a forest community is termed the ‘climax’ and it is a final, mature, stable, self-maintaining and self-reproducing stage of vegetational succession on any given site. Destruction of such forest communities thus amounts to invite an environmental holocaust in an area.
In order to attain proper growth, good yields and maintain fruit quality, apple plants need different nutrients in varying quantities. Nitrogen, phosphorous and potassium fertilizers are extensively used in the apple orchards. According to a report, in Kumaon region, most of the amount of chemical fertilizers is going to apple orchards, rather than to food grain crops. Apple orchards serve as a host for a number of pests. In order to protect the plant a large number of pesticides – fungicides, insecticides, nematicides, weedicides, and rodenticides – are applied in an orchard. Indiscriminate use of chemical fertilizers and pesticides in the apple gardens leaves behind a trail of deadly pollution. These chemicals do not remain confined to an apple orchard, but become a major reason of air, water and soil pollution. Many of the pesticides used in apple orchards are imported ones and are banned in developed countries. Mixing of dreaded chemicals with the food chain is easier in mountain areas than in the plains because of the fact that in undulated areas water carrying life-annihilating pollutant runs faster downstream.
People fondly consuming apples do not know the fact that this fruit is water-guzzling. The mountain areas in which apples are planted often receive high precipitation in the form of rains and snows. Water deficiency reduces fruit size and quality, as well as production. Apple trees have very high susceptibility to drought conditions. Slightest fluctuations in the rainy season and in soil moisture content adversely affect the overall performance of the plant. Apple orchards flourish where there were oak forests earlier. Oak forests create lot of humus and it is this humus that keeps the water in the soil conserved for longer duration. Inadequate rains and short season of or no snowfall lead to shortage of moisture in the soil and then apples need irrigation.
Apple’s water use efficiency is extremely low, which causes a serious phenomenon of excessive water wastage. Very high evapotranspiration rate is the cause of apple’s low water use efficiency. The total annual water requirement of one ha of apple orchard in Kumaon Himalayas, on an average, is 39,08,000 litres. How much water is needed for each kg apple production? The figure is staggering—1153 litres, according to a book, first of its kind, entitled Ecological Impact of Apple Cultivation in the Himalaya by Dr. Vir Singh.
Rapid disruption of the hydrological cycle is another consequence of large-scale apple plantation. Natural oak forests in the Himalayan mountains have always been appreciated for their role in maintaining hydrological cycle and water balance. On the other hand, the different morphological and physiological characteristics of exotic apple trees not adapted to the effective utilization of available precipitation, impair the hydrological cycle and deplete water resources, that too in the area which is already facing an acute shortage of water.
If human labour, fertilizer and pesticide doses, and manure applied in an apple orchard are converted into energy and fruit yielded by apple trees are also converted into energy, we would find that an apple production system is energy-inefficient. The energy output- input ratio must be higher enough if a system were sustainable. The narrow ration is an indicator of unsustainability. Energy budget of apple cultivation reveals that fruit biomass conversion efficiency of the apple trees is extremely low. As many as five units of energy are expended to obtain one unit of energy in net fruit yield. From the energy budget point of viewpoint, it could be inferred that apple production is not sustainable.
The current effects of apple cultivation on Himalayan ecosystems may not be as serious as they would be in a few decades from now. This is reflected in the soil erosion, water resource depletion, hydrological cycle disruption and biodiversity annihilation which follow the systematic replacement of climax forests by apple orchards. Rapidly going on apple cultivation is gradually accentuating ecological degradation in the Himalayas.