Agriculture and Climate Change

Animakshi Bhushan
Sep 19, 2024
16 min read

Updated: Jan 8

This is Part 1 of a series on Indian agriculture relevant to North India, especially Himachal Pradesh. Please follow up for more posts!

Climate change, or the unpredictable but significant change in the temperature and weather patterns of the world is considered to be one of the biggest threats to life on our planet today. Climate change also impacts agriculture through events such as droughts, flash floods and heatwaves, threatening food security of populations and livelihoods of communities dependent on agriculture. Such drastic consequences require our immediate attention to reduce its impact and to help communities understand and adapt to this ongoing phenomenon.

In April, 2024 we carried out a short survey inquiring about some of the agricultural practices in Kinnaur to better understand how equipped people were to tackle the effects of climate change in Himachal Pradesh. We also recorded awareness about recent climate events to further gauge the interest of community members in climate change and global warming. From these we were able to deduce people’s interest in these dynamic topics and a need to present the science behind climate change and its impact on agriculture in a simple yet empirical manner.

Here, we share some of the data collected from our April 2024 survey and also provide a short write-up covering some basics regarding climate change and how it has historically impacted agriculture. We dive deeper into the impact of modern agricultural practices, such as indiscriminate use of chemical fertilisers and pesticides on soil and human health, along with their impact on local biodiversity and the contribution of modern agriculture towards accelerating global warming and climate change. While many of our readers may already be aware of this information, we hope that you will still take away something useful from this article and provide useful feedback for our consideration.

Difference between weather and climate

Organisms, such as plants, animals, and microorganisms, interact with each other and their physical environment - including elements like air, water, and soil. Together, these living and non-living elements make up an ecosystem. Within an ecosystem, organisms interact to create a complex network of relationships that support the flow of energy and the cycling of nutrients. These interactions are heavily reliant on factors such as temperature and rainfall - which are often referred to as the climate or weather patterns. Both climate and weather are environmental variables. While weather refers to day-to-day variations in temperature and precipitation of a place, the climate of a place refers to the weather conditions of that area measured over a long period of time (over 30 years). Therefore, we can say, “Shimla has a cooler climate even though the weather is hot today.”

What is climate change?

Climate change is the unpredictable but significant variation in the climate of the world. While natural climate cycles have continued throughout the history of our planet (such as glacial advances and retreats causing events like ice ages in our history), anthropogenic climate change - that is change in climatic cycles due to human activities - is a more recent phenomenon. Globally, the average temperature has risen by roughly 1.18 degrees Celsius above pre-industrial levels. This increase in average temperature over a span of about 200 years of industrialization is quite significant when compared to the last ice age and glacial retreat that happened roughly 12,000 years ago. This abrupt rise has also been proven to be linked to an increase in greenhouse gases, especially carbon dioxide - which started rising at record speed after the industrial revolution (video link to understand this connection more: https://www.youtube.com/watch?v=IXHOc2rmSPM). Let’s go back to understanding the link between climate change and agriculture. As discussed earlier, interactions within the ecosystem are complex and affect flow of energy and cycling of nutrients. For instance, change in land-use can significantly contribute to destroying natural energy and nutrient cycles - for example, cutting of trees makes the land more prone to landslides, and affects natural soil and the life it supports. Similarly, excessive usage of fertilisers, pesticides and converting forests into farmland, all have consequences on the climate affecting the delicate balance of the ecosystem, and we explain this link in the subsequent sections.

Industrial Revolution and the environment

The Industrial Revolution followed several technological and industrial advancements which were directly responsible for releasing massive amounts of chemicals and other toxins into the environment. Immediate benefits included reduced manual work and better profits and any long-term impacts on the environment were not considered. In this background, Rachel Carson, an American scientist and writer published her book ‘Silent Spring’ which talked about how pesticides not only killed pests but also killed other species of insects, birds and wildlife. Her book also questioned whether such pesticides were safe for human health when they were capable of killing so many plants and animals. Her claims were refuted by chemical manufacturers and industrialists, who resisted Carson’s call to critically think about environmental pollution. As her book gained popularity among citizens, a one of its kind environmental movement started in the U.S. and on April 22, 1970, millions of people came out in support of Carson and her message on toxic chemicals polluting the American soil. A direct impact of this public pressure were scientific studies confirming the toxic impact of pesticides and chemical fertilisers on plant, animal and human health. This day (April 22) is now commemorated as Earth Day worldwide.

Green revolution and the Indian context

In India, the Green Revolution was crucial in making our country self-sufficient in food production. The success of the Green Revolution cannot be celebrated enough - India exported 85 metric tonnes of cereals in the last three years (2021-23) alone. This was achieved alongside schemes such as PM Garib Kalyan Yojana which provides free grains (rice and wheat) to over 800 million people each year. Such big numbers only highlight how far our country has come from deadly famines and food insecurity. We are not only self-sufficient in food but are now food-excess. Needless to say, this would not have been possible without the tireless efforts of scientists such as Dr. M.S Swaminathan, Dr. Gurdev Khush, Dr. Dilbagh Singh Athwal, among others who facilitated technology transfer and expanded irrigation infrastructure for agricultural self-sufficiency. While use of high-yield varieties of seeds and synthetic fertilisers and pesticides was critical to the success of the Green Revolution in the 1960s, little has been done to counteract the negative impacts of chemicals in agriculture. Heavy subsidies on chemical fertilisers, especially urea, still continue and have led to skewed and unrestricted use of NPK (nitrogen, phosphate and potash). As a result, soil health and fertility is significantly impacted due to reduced soil organic carbon (Addition of extra nitrogen makes soil biota more active, and they consume and release more carbon, reducing long term fertility of the soil and soil organic carbon - SOC).

Fertilisers impact soil health

Research from World Food Laureate and soil scientist, Dr. Rattan Lal, has pointed out that over 60 percent of Indian soils have a soil organic carbon (SOC) of less than 0.5 percent against the recommended value of 1.5 to 2 percent, making most Indian soils extremely deficient in organic carbon and putting several different types of soils at the risk of extinction. Yes! Soils too can go extinct when they lose their original characteristics to overgrazing, degradation and erosion. An example of this can be seen in our own backyard in brick kilns of Himachal Pradesh, Punjab and Haryana. Fertile top layers of red and alluvial soils (estimated at more than half a meter) are stripped to make bricks. Rapid urbanization has increased the demand of bricks phenomenally, and led to the rise of an unorganized brick sector willing to fill the gaps at huge environmental costs rendering local soils to further degradation and little to no hope of revival.

Coming back to the soil organic carbon (SOC) - it is essential in maintaining the microorganism population of the soil and is key in maintaining soil quality, soil fertility, agricultural profitability and for fixing atmospheric CO2 — an important and easy solution to our fight against climate change. Low SOC is also linked with lower micronutrients such as iron, zinc, etc. and affects human health directly. According to the National Family Health Survey 5 (2019-21), 25% men and 57% percent women suffered from iron-deficient anemia that can be associated with our soil health as well.

Ripples of the Green Revolution have been felt even more severely in states of Haryana and Punjab, where wheat-paddy monocultures, excessive use of fertilisers, soil degradation and depletion of groundwater are contributing towards desertification of these States. It is estimated that over 90% of Punjab will be lost to desertification by the end of 2045 and the state will lose most sources of potable water. While this might come as a surprise to many who grew up reading and learning about Punjab as the “Bread Basket of India”, the reality is that the costs of environmental damage are often too high, too steep and irreversible. In the case of Punjab, excessive fertiliser use has also increased soil salinity to the extent that many Punjabi districts are now transitioning to shrimp farming as it is impossible to grow paddy or wheat in alkaline soils. Such extreme shifts in cultivation will undoubtedly affect bird, insect, and pollinator populations too, and further disrupt the ecosystem services they provide, triggering more undesirable ecological impacts in the future.

Chemical fertilisers impact ecosystem health

Unsupervised use of chemical fertilisers is also a major cause of water pollution and air pollution. Many synthetic fertilisers leach into the water table and contaminate the groundwater. Fertilisers may also contaminate nearby rivers and lakes through surface runoff and cause algal blooms through the process of eutrophication (nutrient enrichment of freshwater). Such nutrient-rich lakes and rivers are directly responsible for loss of biodiversity in aquatic ecosystems as the algal blooms block sunlight from penetrating into the water and negatively impact water quality. The excess nutrients also cause plankton/aquatic plant numbers to increase and compete for oxygen with fish and other aquatic animals.

In India, most lakes are in a medium (mesotrophic) or high (eutrophic) nutrient state. In Himachal Pradesh, the famous Renuka Lake (Sirmaur) and Rewalsar Lake (Mandi) are considered to be hypereutrophic due to extremely high levels of nitrate deposition from chemical fertilisers, livestock wastes, and sewage treatment plants. Loss of aquatic biodiversity also impacts terrestrial ecosystems as the two are closely interlinked with one another through delicate biogeochemical cycles of water, carbon, nitrogen, sulphur and phosphorus. For instance, nitrogen is a greenhouse gas and contributes to global warming. Events such as flash floods, acid rain, nutrient pollution and global warming are therefore direct consequences of upsetting the delicate balance of these nutrient cycles.

Chemical fertilisers and human health

Recent studies have shown that chemical fertilisers may play a role in conditions such as Blue baby syndrome (methemoglobinemia) where nitrates in blood compete with oxygen and reduce the binding ability of oxygen causing the skin of babies to appear blue or grey. Testicular & gastric cancers have also been found to be associated with high levels of sodium nitrate in soil. Traces of heavy metals such as mercury, arsenic and cadmium have also been reported in synthetic fertilisers as well. These have serious implications on development of the fetus and other neurological conditions. While chemical fertilisers help with plant growth, it is important to be aware of their dangers, especially because these fertilisers stay in the soil for a long time and using more than what is needed for the plant harms humans and the environment.

Pesticides impact human health

Another major component of modern farming is the use of chemicals to minimize insect damage and reduce weeds. Herbicides (weeds), insecticides (insects), fungicides (fungi) and biocides (all living things) are some of the different types of pesticides available in the market. As compared to natural or organic pesticides (for example: neem oil, chilli oil, etc) most synthetic pesticides are created to kill specific pests and have to be applied in a targeted way.

Pesticide treadmill is a term that agriculture scientists use to describe an important drawback of relying on synthetic pesticides to eliminate pests. Most insects, including pests, strive to survive. On applying a pesticide to a plant many individuals of a particular pest will get killed, but a few may survive and reproduce. This starts a never ending cycle where the next generation of pests is stronger and more resistant to old pesticides and requires more potent and toxic formulations. This cycle of developing powerful pesticides to counteract newly adapted pest populations is called the pesticide treadmill. The costs of new pesticides are often higher and add onto the input costs of farming. Any leftover pesticides from the previous season also get wasted as newer varieties are needed to control these resistant pest populations. Such synthetic pesticides (unlike natural pesticides) do not break down naturally and are unable to recycle themselves through the ecosystem. They either stay in our food or in our environment. Worse still, many have been proven to directly impact human health. I list some of the major synthetic pesticides categories below:

Organophosphates - are related to nerve gases used in WWII and are highly toxic for the first few days after they are applied. They break down eventually but in the narrow window after application can result in severe damage to the nervous system of pollinators and animals. In humans they cause nausea, vomiting and respiratory illnesses. Examples: Chlorpyrifos, Malathion, ODM.
Chlorinated hydrocarbons - are pesticides that do not break down as easily and have been established as metabolic disruptors and even linked to cancer in birds and animals, including humans. Atrazine is an example of one such pesticide.
Inorganic pesticides (i.e. those which do not contain carbon) - usually contain mercury and arsenic that remains in the soil and ecosystem long after they have been used. These easily enter the food chain and cause neurological deficiencies in children leading to neurological impairments and increased death rates in young adults.
Neonicotinoids - are another class of pesticides related to nicotine and are extremely toxic to many insect species, including bees and have been linked to Colony Collapse Disorder in Europe.

I also provide a table (Table 1) of commonly used pesticides and their potential implications on human health below. See if you recognise any of the names and if you use them in your practice and comment to start a discussion with your peers.

Table 1: Commonly used pesticides and their impact on human and animal health.

S. No.	Pesticide Type	Chemical Name	Trade Names	Effects on human and animal health
1.	Fungicide (broad spectrum)	Tebuconazole	Tebucon, Buonos, Indazole, Folicure, Tebura, etc.	- Endocrine disruptor in humans; - Causes liver injury in bats, zebrafish and mice; - Causes renal toxicity in rats; - Potentially neurotoxic, immunotoxic and carcinogenic to earthworms; - Banned in EU in 2009
2.	Fungicide (broad spectrum)	Carbendazim	Clonezim - 50, Bavistin, Bestin, Saaf, Samartha, Carben, etc.	- High doses cause infertility and testicular loss in laboratory animals; - Residue from carbendazim blocks nuclear division in human cell lines; - Possible human carcinogen; - Banned in Australia, USA and EU
3.	Fungicide & Bacteriacide	Dodine	Superstar 65 WP, Doddy, Danny, Noor, etc.	- Endocrine disruptor in humans; - Severe eye and skin irritant in humans; - Thyroid changes observed in dogs that were exposed to Dodine; - Highly toxic to fish
4.	Fungicide	Mancozeb	Sunzeb M-45, Risezeb M-45, Indofil M-45, Tata M-45, Abic, etc.	- Altered thyroid function, neurotoxicity and teratogenicity in humans; - Liver injury in mice; - Carcinogenic in lab animals after chronic exposure; - Highly toxic to aquatic life
5.	Fungicide	Myclobutanil	Matrix, Index, Cryonil, Systhane, Boon, Cygnet, Valour, etc.	- Eye irritant - Impacts fertility of unborn child; - Liver injury (hepatotoxic) in laboratory animals; - Affects reproductive ability of lab animals; - Bioaccumulates in soil and environment (therefore can affect human health long term); - Highly toxic to aquatic life
6.	Fungicide	Difenoconazole	Score (syngenta), D-zole, Difen, Concor, Scotch, Crease, Redeem, etc.	- Eye and skin irritant in humans; - Low acute toxicity in humans; - Kills juveniles and cocoons of earthworms; - Kills other beneficial fungi species; - Induces cardiovascular toxicity in zebrafish - Chronic use in rats, mice and dogs showed reduced body weight.
7.	Insecticide (broad spectrum acaricide + organophosphate)	Oxydemeton-methyl (ODM)	Metasystox, Alphosides, Cyper, etc.	- Maternal exposure to ODM in humans has been associated with congenital abnormalities; (including cardiac, pulmonary, eye, cerebral and facial abnormalities); - Reproductive toxicity in male and female rats; - Musculoskeletal and cardiovascular teratogenicity in chick embryos
8.	Insecticide (acaricide & miticide + organophosphate)	Chlorpyrifos	Clorex, Agrichlor, Predator, Darban, Killer- 505, Dursban, Terminator, Tricel, etc.	- Affects nervous system in humans on exposure (can cause headaches, blurred vision, dizziness, confusion, weakness and nausea); - Long-term use may lead to bone weakness, increased risk of blood clots, gastrointestinal disturbance; - Higher exposure in humans causes poisoning (tremors, salivation, seizures, coma and even death); - Developmental effects in fetus; - Very toxic to many bird species; - Reduced clutch size with thinner egg shells were reported in some bird species; - Highly toxic to aquatic life
9.	Insecticide (organophosphate)	Malathion	Himthion, Milthion, Suthion, Cythion, Shrithion, Mal - 50 etc.	- Endocrine disruptor; - Affects nervous system in humans on exposure (giddiness, fatigue, confusion, slurred speech, respiratory depression, loss of consciousness, even coma); - Eye and skin irritant; - Liver carcinogenicity in humans at excessively high doses; - Highly contaminating (clothing, belt, shoes, etc. cannot be reliably decontaminated and should be incinerated); - Liver tumours, nasal tumours, oral tumours, and non-Hodgkin's lymphoma reported in mouse and rat models in laboratory experiments
10.	Insecticide	Fenazaquin	Magician, Magister, SA-Magnitude, Planar, etc.	- Moderately toxic to humans through oral route - Respiratory tract irritant in humans (no long-term effects identified) - Toxic to terrestrial and aquatic animals
11.	Insecticide (broad-spectrum)	HMO (Horticulture Mineral Oil)	HP HMO, HerbOil, Servo Oil, etc.	- Eye and skin irritant for some people - May be allergic to some - if ingested; - Smothers most insects, including beneficial pollinators; - Toxic to fish and bees (hence sprayed at dawn and dusk) - May burn sensitive plants species
12.	Insecticide	Tree Spray Oil (TSO)	HP Spray Oil E, PetroStar- TSO, etc.	- Smothers most insects, including beneficial pollinators; - Effects on humans unknown

Many of these pesticides stay in the soil for years (even decades) in lethal quantities, and in a way similar to fertilisers they contaminate groundwater and freshwater systems such as ponds, rivers and lakes threatening the entire ecosystem at large. Some may even evaporate and precipitate in areas far away from the original sites affecting entire ecosystems or biomes, and the humans that inhabit it. In the Green Revolutions states too there is a disproportionate rise in cancer, stillborn babies (blue-baby syndrome) and congenital disabilities, much of which is seen as the human cost of using high amounts of pesticides. However, despite possessing this knowledge, indiscriminate use of many synthetic fertilisers and pesticides continues even today. When we lose our soil we ultimately lose our health in ways that science and technology is unable to correct at the moment, and we must use these chemicals very carefully and judiciously.

In conclusion - How can we conserve our environment?

We will share organic solutions to problems faced in modern farming in our next post. In the meantime, some general advice involving techniques such as integrated pest management (IPM) can be used to naturally control pests and to try minimizing chemicals as much as possible. Simple steps such as polyculture, crop rotations, intercropping and agroforestry are covered under this:

Polyculture: Crops that consist of only species (monoculture) are at higher risks of disease and infection.
Crop rotation: Planting different crops in a field each year for a few years in a rotating cycle helps serves two purposes - a) keeps the soil healthy by allowing it time to replenish, especially when nitrogen-fixing plants are used for some years, and b) naturally breaks the reproductive cycle of specific pests that usually prefer a particular crop.
Intercropping: Intercropping involves planting of two different types of crops in alternate rows in one field. This ensures that the top soil remains intact when one of the crops is harvested (assuming that the two crops are harvested at different times of the year). Farmers can also plant something that attracts prey insects - or insects that prey on pests and use that as a natural pesticide.
Agroforestry: Planting trees and crops in the same field is also helpful in preventing soil erosion as the roots of the trees hold the top soil in place. These trees can also be used for timber, firewood and fruit.

Other techniques such as terrace farming and contour plowing also prevent soil erosion, especially in hilly terrains. Reducing tillage as much as possible also helps in maintaining soil quality as the top soil is not easily removed. While most agriculturalists in Kinnaur generally follow these practices, it should be pointed out that indiscriminate use of chemical pesticides and fertilisers - even alongside IPM techniques negate any positive impact of IPM techniques. We should be mindful of the fact that our economic growth cannot and should not come at the cost of our soil, environment and people's health.

Finally, these techniques are only helpful when they are supported by good government policies. We already know that senseless subsidies do not help our environment and are only as good as a short-sighted five year plan. We should ask our political representatives to assist the farming sector by passing policies that encourage direct benefit transfer or DBT to the farmer’s bank account in place of synthetic fertiliser and pesticide subsidies. The farmers of our community and our country should make their own decisions on which fertiliser system they want to follow.

Results from survey

In April 2024, we carried out an online survey to better understand their preferences in agriculture. We collected data from representatives of 31 families practicing agriculture in Kinnaur. Some of the results have been highlighted here to shed light on community members practicing agriculture. We used this data as a starting point and collected more information from community members residing in different parts of the Himalayan region to better understand agricultural practices, knowledge and awareness on matters relating to unsustainable agricultural techniques and steps to mitigate the effects of our actions on soil, crops and ecosystem health.

Figure 1: Age group of participants

Most members who participated in the survey were in the 25-45 years age bracket.

Figure 2: Family membership

The average family members of participants was 4-12 members.

Figure 3: Self-reported awareness of climate events

Most participants reported that they were either ‘very aware’ or ‘aware’ of the threats of climate change.

Figure 4: General Awareness of climate events

Members were equally aware and unaware of the impending desertification of Punjab.

Figure 5: General awareness of climate events

While most participants were aware of the direct impact of climate change on biodiversity, many were not sure about the degree of impact.

Figure 6: Trends in agroforestry

Most participants planted trees along with other crops - but these data were skewed towards apple trees (29/31 participants). We will need to collect more data to understand how many families engage in monoculture.

Figure 7: Trends in agricultural practices

Synthetic pesticides and fertilisers were found to be commonly used by families. We will need to collect more data to understand how many families are able to restrict the use of these chemicals and their reasons for choosing them in the first place.

Figure 8: Scientific data on soil health

Most community members did not have accurate data to measure soil health.

Figure 9: Using natural forms of urea

Use of natural forms of urea is prevalent in the community.

Figure 10: Using other natural fertilisers

Other natural fertilisers like Jeevamrut are not preferred by the community. However, this is not a big concern as there may be cultural reasons (including cropping patterns, temperatures and precipitation) for this preference. We need to collect more data to understand natural fertiliser preference of the community.

Figure 11: Use of NPK & other chemical fertilisers

High use of synthetic fertilisers including NPK was reported.

Figure 12: Reasons for using synthetic fertilisers in relatively higher quantities

Reasons for using synthetic fertilisers in higher quantities included lack of strong supply chains for organic products, advice from community members and shopkeepers, inability to find labour for traditional techniques and input costs.