Mushroom Crop in Agricultural Waste Cleanup

1. Introduction

Pollution is a major threat for environmental sustainability. Vehicle emission, industrial effluents, agricultural wastes and municipal waste are leading environmental pollutants. Previously, agricultural waste was known to be the minor cause of pollution. But the intensive agriculture, espoused by increasing population and food demand, has resulted in farmers resorting to unsustainable practice of burning excessive agricultural wastes to clear the land for subsequent crops. Estimated data shows that 62 per cent of the 22 million tons of surplus paddy straw is burnt in the field in India (Gadde, Bonnet, Menke, & Garivait, 2009). The practice of burning straw and dumping of waste affect the air, soil and water quality in addition to the life of farm animals and changes the microclimate of the crop. Crop and animal waste produced in agricultural farms are being utilized in many forms such as manure, household fuel, animal feed, vermi-compost, etc. But still, the bulk of crop and animal waste remains unutilized. Therefore, a sustainable approach is required to capitalize on the underutilized bioconversion potential of agricultural waste. Mushroom farms are useful as bioconversion sites of agriculture residue and produce quality protein to meet the increasing protein demand in the country. Mushroom farming is a profitable venture for the farmers and means of bioremediation for the environmental sustainability.

1.1. Global and National Status of Agricultural Waste

According to the data given by “Waste Atlas”, 2.0 billion tonnes of waste per year is produced globally. The current total waste estimate was 8.8 billion tonnes from May 2012 (“Waste Atlas - Interactive map with visualized waste management data,” 2017). The current municipal waste is estimated around 1.9 billion tonnes. Out of total waste, 30% of municipal waste remains uncollected and of the remaining 70 percent, it is utilized/disposed of in different ways as given in Table-1.

Table 1.

Global Municipal waste utilization and percentage

Sl.No.	Management types	Percentage
1.	Landfills and dumpsites	70
2.	Recycle	19
3.	Energy production	11

Source: Waste Atlas - Interactive map with visualized waste management data, 2017

In global waste, India is also one of the major contributors. According to data, around 400 million tonne of waste is produced by India annually (Raju, Kumarappa, & Gaitonde, 2012). Other data suggests that the total solid waste generated by India per year is around 960 million tons (Pappu, Saxena & Asolekar, 2007). Out of the total agriculture waste, the organic waste contributes around 36 percent while inorganic waste generated by industrial and mining sector is 30 percent. This imposes the challenge to identify suitable waste management strategy for agriculture residues.

Figure 1.

Total waste percentage in India