In pre-industrial agriculture, animals were valued not only as producers of milk and meat but also as means of providing manure which was essential for maintaining production from cereal and vegetable fields.

From the middle of the 20th century, mechanisation of agriculture and introduction of artificial fertilisers and industrial foodstuff, however, led to the separation of the age-old link between crop and livestock farming. Machines began to replace human and animal power for preparing soil, planting, weeding, and harvesting crops. Since the 1930s, newly developed, high-yielding crop varieties started replacing traditional varieties. Most of these new varieties required application of synthetic inputs such as pesticides and fertilisers, which is the beacon of the agricultural revolution in 1960’s to ensure food production. In the last half of the 20th century, grain production tremendously increased at the cost of ecological upsets and disruption of natural equilibrium at large.

Use of fertilisers in agriculture is both desirable and detestable as far as crops health condition and their effect on the environment and associated biodiversity is concerned.

With technological development and the quest to get more harvest and secure food production, traditional approaches vanished consequently and in the last few decades most of the world’s agriculture seems to have transformed into "industrial agriculture."

Due to industrialisation, mechanisation and new concepts, large-scale changes in practices have been observed resulting in decline of crop diversity due to planting culture. Traditional farms include grains, root crops, vegetables, spices, medicinal plants, livestock, and trees for lumber, fruit, and firewood. In contrast, most modem farms are monocultures - that is, they have only one crop species planted over a large area thereby having less associated diversity such as insects, birds, and soil organisms and were more beneficial to the plants. With the use of chemicals, pesticides and insecticides, the relation of plants and soil organisms has largely been tilted.

The practice of monoculture rely more on use of pesticides. In order to get rid of the problem insects becoming pests and other pathogens (disease-causing organisms) pesticides or insecticides are resorted to. These insects can readily find their food sources more easily in homogenous crops or monocultures than in heterogeneous crops or diverse crop mixtures. Therefore, in monocultures there is lower population of biological control agents such as spiders, wasps, dragonflies, and predatory beetles, which are enemies of pests.

It has also often experienced that pest resistance and secondary pest outbreaks require increased amounts of pesticides or more toxic chemicals to minimise its effects. This induced fertility of the agricultural lands with many of the modern agricultural techniques cause tremendous erosion and contamination of the earth’s topsoil.

On account of increased demand for use of the industrial inputs in agriculture the genetic diversity of crop has been affected. Earlier hundreds of edible plant species were grown in different parts of the world while now about 60 per cent of the world diet constitute of rice, wheat and corn. This can also be attributed to replacement of high yielding plant and crop varieties, causing genetic erosion.

The process of genetic erosion is a nightmare in the agriculture sector due to which important species and varieties would be lost that would be an irreparable loss on the face of earth. According to the Food and Agriculture Organisation of the United Nations, 75 per cent of crop diversity was lost during the twentieth century. Modern varieties have supplanted traditional varieties for 70 per cent of the word’s corn, 75 per cent of Asian rice, and half of the wheat in Africa, Latin America, and Asia. In 1950, India had 30,000 wild varieties of rice, but by 2015 only 50 are expected to remain.

Use of fertilisers and pesticides have dire impact on the biodiversity at the micro level resulting in dire consequences in the long run. Many individuals of some bird species have died after eating sprayed insects. Pesticides from agriculture flow into aquatic systems through runoff of surface water, soil erosion, and drainage into groundwater. Pesticide residues in streams, lakes, bays, and coral reefs kill aquatic plants and zooplankton (microscopic animals) that fish require for food. Pesticides in water have been shown to increase the mortality of young fish and amphibians as fertilisers and pesticides release harmful chemicals, which are washed into lakes, and rivers causing water pollution. Toxic chemical sprays used on crops for pest control threaten many of the earth’s most important species - pollinators and soil organisms.

In the past farmers applied minimum mineral fertilisers for better crop production on their lands with traditional land use system, today they apply eight times as much. In the global perspective, according to an estimate in northern Europe, fertiliser use has increased from about 45 kg/ha to 250kg/ha since 1950. In the same period, wheat yields in France increased every year, from about 1.8 tonnes/ha to more than 7 tonnes/ha. Fertiliser application currently accounts for 43 per cent of the nutrients that global crop production extracts each year, and the contribution may be as high as 84 per cent in the years to come.

There is a general consensus about the way agriculture is evolving in response to demographic and economic trends. World population will probably peak at some 8,000 million around 2030, when two out of every three people will live in towns and cities. Rising incomes will create a disproportionately higher demand for food, meaning that over the next three decades food production will need to increase by about 60 per cent. Nearly all of the increase in production will have to come from developing countries through intensification of agriculture, i.e. more yield per unit time and per unit area.

Mismanagement of fertilisers, whether organic or inorganic, results in inefficiencies of plant nutrient use, leading to a loss in farmers’ profits, potential damage to the environment and inefficient use of energy. One of the most serious problems associated with improper fertiliser use is a sustained imbalance in the application of nutrients, causing a loss in soil fertility, reduced crop yields, and environmental degradation. When nutrients are over-applied they can have an adverse effect on water quality both surface and groundwater. The implementation of proper soil management practices, such as timely site-specific and crop-specific nutrient placements and conservation tillage, are highly effective in optimising the efficiency of nutrient use.