Climate change is affecting all four dimensions of food security: food availability, food accessibility, food utilization, and food systems stability. It is also affecting human health, livelihood assets, food production, and distribution channels, as well as changing purchasing power and market flows. Keeping in view, the present chapter is focusing mostly on biochar. Biochar is usually produced by pyrolysis of biomass at around temperature range of 300–600°C. It is under investigation as an approach to carbon sequestration to produce negative carbon emissions. Present agriculture is leading mining of nutrients and reduction in soil organic matter levels through repetitive harvesting of crops. The most widespread solution to this depletion is the application of soil amendments in the form of fertilizers containing the three major nutrients. The nitrogen is considered the most limiting nutrient for plant growth useful for protein builds, structures, hormones, chlorophyll, vitamins, and enzymes. Biochar may be added to soils to improve soil health, improve soil fertility, and sequester carbon. However, the variable application rates, uncertain feedstock effects, and initial soil state provide a wide range of cost for marginally improved yield from biochar additions, which is often economically impracticable. There is a need for further research on optimizing biochar application to improve crop yields.
Part of the book: Applications of Biochar for Environmental Safety
Plants produce secondary metabolites for defense and based on the biosynthetic pathway, these chemical compounds are broadly divided into three categories namely nitrogen-containing compounds, phenolic compounds, and terpenes. Essential oils and other such compounds are known for their biological activities. The extraction of essential oils is a challenging aspect for researchers in the field of natural products. Hydrodistillation is a time-consuming and very tedious method. Nowadays, accelerated solvent extraction, supercritical fluid extraction, subcritical water extraction, microwave hydrodiffusion are promising alternatives for conventional methods with several advantages. Essential oils have several biological activities in the field of pharmacological, ethnopharmacological, pesticidal, etc.
Part of the book: Essential Oils