Impacts of climate change and adaptation measures for agriculture

Tác động của biến đổi khí hậu và các biện pháp thích ứng cho nông nghiệp

Agriculture is one of the most sensitive sectors to climate change. People often say agriculture is “weather dependent”, which reflects the high vulnerability and vulnerability of agriculture to climate and climate change. In the context of the increasingly serious global climate crisis, how to seek advantages, avoid disadvantages, and minimize The adverse impacts and risks brought by climate change on agricultural production, while fully exploiting potential opportunities for agricultural development and transformation are common issues in countries around the world. facing the world.

Impacts and risks of climate change on global agriculture

Sixth assessment report of the Commission The Intergovernmental Panel on Climate Change (IPCC) once again shows that climate change is causing many pressures and threats to the farming, livestock, poultry, forestry and fisheries sectors. and aquaculture aquaculture.

Over the past 50 years, agricultural productivity growth in the world's mid- and low-latitude regions has slowed due to climate change, The climate has comprehensively affected crop productivity and quality, grassland quality, forest distribution, fish distribution and other issues. aspects. For example, according to the results of multi-model comparisons, which take into account the combined effects of many factors and do not consider adaptive capacity, climate change has an overall negative impact on productivity of four major global crops (corn, wheat, rice and soybeans). ) The emissions scenario would reduce the yields of these four crops by an average of 25% by 2100 and would reduce the nutrient density of some crops.

Climate change are also changing the suitability of some important phenology and crop growing areas. Under a high emissions scenario, the climate of 10% of global crop and livestock areas will become unsuitable. compatible with current crop and livestock farming activities in 2050. For example, heat stress in tropical regions will have a very serious negative impact on the production of crops and vegetables that are easily affected by temperature. high and drought stress during pollination and fruit set, thereby affecting yield and quality. Increasing average global temperatures may also increase the frequency of some pests, causing Many crops are at higher risk from pests and diseases.

Extreme climate events are affecting productivity in the horticulture and fisheries sectors. From 2015 to 2020 , the proportion of countries that have experienced three or more different extreme weather and climate events at the same time has exceeded 50%, and the proportion of countries that have experienced at least one extreme weather and climate event has nearly reached 60%. These data show that extreme weather and climate events have become common in most countries around the world and have a significant impact on safety. food security, food security and global rural livelihoods.

In addition, the risks of climate change to agriculture are complex and widespread. For example, the The impact of climate change on the total amount of water resources as well as their spatial and temporal distribution will indirectly affect crop production and the increased frequency of extreme events such as heavy rains and droughts. Drought will directly threaten crop yields. In rainy conditions, the combined effects of heat and drought could reduce corn yields in Europe by more than 60%.

The negative impact of climate change on agriculture and food security will increase hunger, malnutrition and other diet-related risks, thereby affecting the achievement of the United Nations Sustainable Development Goals (SDGs), especially achieving zero hunger. Relevant studies estimate that more than 50 million people worldwide could be malnourished nutrition by 2050. Without effective adaptation through international trade and other policies and measures, the number of malnourished people worldwide could reach 73 million.

In addition, climate change will exacerbate food and malnutrition crises in some areas where socioeconomic stability is already unstable. Report "Status Food Security and Nutrition in the World 2021" published by the Food and Agriculture Organization of the United Nations (FAO) shows that low-income countries are vulnerable to conflict and harsh impacts. climate has the highest increased disease incidence. The region with the highest increase in malnutrition rates will be affected by a variety of factors through 2019. Africa is the only region affected by a combination of conflict, harsh climate andeconomic depression. Malnutrition rates will increase and threaten society. 

Concepts and technology options for agriculture adapting to climate change

Agriculture is the basic industry of the national economy, food security is the foundation of social stability and national security, agriculture adapting to climate change becomes a priority. leading priority. Currently, many independent adaptation plans have been implemented around the world in different regions, different industries and at different levels. As an industry "Depending on the weather", agricultural workers have also independently applied a number of adaptation plans to seek advantages and avoid disadvantages. But in general, the scale of global agricultural adaptation with Current climate change is not enough to support the sustainable development of agriculture and the realization of the United Nations Sustainable Development Goals, nor is it enough to fully offset the negative impacts. The potential of climate change for crops. production. Many scientific and feasible adaptation plans implemented in various regions of the world still lack effective economic incentives or relevant policy support. Therefore , how to motivate businesses and agricultural workers to implement more effective adaptation measures is an important issue facing policymakers today.

With With the development of the concept of ecosystem services, the international community has gradually recognized the role of ecosystems in climate adaptation. The concept of "Ecosystem-based adaptation (EbA)" was created to enhance the adaptive capacity of communities and reduce the pressure of climate change on ecosystems by managing and restoring ecosystems and their services12 . EbA has can effectively improve agriculture's resilience to climate change and bring many mutual benefits. On the other hand, EbA decision-making must also consider the impact on different groups and ecosystems, otherwise it will affect adaptive capacity and hinder sustainable development.

Currently, the main adaptation measures in the agricultural sector include the following four aspects.

One is species replacement . That is, research and promote plant and animal varieties with better stress resistance to improve resistance to waterlogging, salinity, alkalinity, heat, drought, etc. Studies have shown that by the end of this century, 39% of the world's crops may need to be updated with new varieties adapted to climate change to effectively mitigate the impact of climate change on crop production and increase crop productivity. . Related studies also show that, compared to the case of not applying adaptation measures when the temperature increases from 1 to 5°C, adaptation measures such as drought-resistant varieties, increased watering, and mulching Straw will increase the average crop yield by 7 times. % to 15%.

Second is adjusting the planting season and field management  .For example, by delaying flowering and increasing grain closure, wheat can improve its ability to adapt to increased temperatures, thereby reducing yield and protein loss. For example, research shows that compared to the period 1981-2010, if flowering slows down while increasing the grain filling rate, under the RCP8.5 scenario (high greenhouse gas emissions scenario), rice yield Global wheat will increase by 9.6% in 2010. It is estimated that by the end of the century, climate change may cause Vietnam's maize sowing time to be 2 to 6 days earlier and shorten the planting season from 3 to 6 days, adaptive adjustment of planting season can avoid up to 6% of damage caused by climate change to maize yield.

Third is irrigation technology . Promoting irrigation technology and improving irrigation capacity is one of the most effective solutions for agriculture to adapt to the adverse impacts of change. climate. For example, India's promotion of irrigation structures and technologies in rain-fed agriculture has brought about very good adaptation effects. From 1970 to 2009, the promotion  ;Irrigation technology has increased India's wheat yield by 13%, while minimizing the adverse effects of high temperatures.

Fourth is changing the planting structure cultivation and regulation . Increased temperatures and cumulative temperatures will shorten the growing period of crops and lengthen the growing season, and will cause the boundaries of growing systems Polyculture continues to shift north. Regional crop structure is the result of the long-term adaptation of agriculture to local climatic, ecological and socio-economic conditions. Studies in the United States show that without changes in planting patterns, rising temperatures in the United States by 2070 under the RCP8.5 high emissions scenario will lead toup to 31% of US crop income is lost, but adjusting crops to better adapt to climate change could reduce lost productivity by 16% - 21%.


Climate change adaptation concepts related to agriculture

Climate smart agriculture.  This concept, proposed by the Food and Agriculture Organization of the United Nations (FAO), means continuously improving agricultural productivity and enhancing the resilience of agriculture to natural disasters and climate change. climate change, while adapting better to climate change, slowing greenhouse gas emissions in agriculture and enhancing food security, agricultural production methods and development models for development. agricultural development. Specific action plans in line with this philosophy include sustainable dairy farming, climate-smart value chains, etc. There are now Agricultural Alliances around the world. Climate Smart Industry and the many initiatives within this alliance are promoting climate change mitigation and adaptation across the entire agricultural system.

Suitable Agriculture climate resilience. This concept mainly emphasizes reducing the impact of climate change through adaptive behaviors in agriculture and improving the resilience of agricultural systems climate change. This concept also specifically proposes that nature-based solutions (NbS) can be used to improve agricultural ecosystems and promote the role of agriculture in mitigate climate change.

For example, the International Maize and Wheat Improvement Center (CIMMYT) predicts that drought and rising temperatures will reduce global corn production by up to 30% by 2030. To solve this problem, CIMMYT has successfully developed more than 100 new maize varieties and promoted them in Africa. By using drought-resistant maize varieties, Zimbabwean farmers can produce 600 kg of corn/hectare in drought years, can provide an additional income of 240 USD, enough to feed a local family of 6 people for 9 months.

Another example, the Fund Agricultural Development International launched the Smallholder Agricultural Adaptation Project in 2012 to meet the agricultural development needs of different African countries, helping them establish diversified agricultural production models. and introduced technological means, such as sending weather forecasts to other countries. real-time via SMS, allowing farmers to understand weather changes in a more timely manner. As of 2017, the program has distributed about $305 million in aid. The continent currently has 390 digital solutions increase agricultural productivity in Africa by 73% and increase average farmer income by 37% .

Nature-based solutions (NbS). This concept refers to considering mitigation and adaptation solutions based on ecosystem function. Currently, the world is strongly promoting the application of NbS in many different fields such as mitigation and adaptation. However, the current number of NbS deployments worldwide is still limited and there are gaps. clarity in implementation across countries.

The 2020 Adaptation Gap Report counted 942 NbS-enabled projects, with a further six NbS options proposed in the six countries world, specifically Brazil, Colombia, Indonesia, Peru, United Kingdom and United States. Forty countries have not implemented a program and 30 countries have implemented between 40 and 91 programs. The number of NbS projects in China is from 1 to 5, with an average of 11. It can be seen, how to design and deploy NbS solutions according to local conditions and realize the huge potential remains an important issue facing all countries and regions.

Regenerative agriculture.  The idea, developed developed by the Rodale Institute, addresses no-till crop rotation and humus organic matter planting to increase agricultural productivity, reduce energy and chemical inputs, and improve soil health. The agency's preliminary research shows that regenerative agriculture, as a comprehensive innovation in agricultural production models, can not only reduce energy inputs but also increase farmers' profits, and importantly most importantly, reducing greenhouse gas emissions and improving agriculture's resilience to climate change