Climate Change

CROPPING PATTERN

Cropping pattern refers to the proportionate area under different crops during an agricultural year and growing season refers to the period between bud burst and leaf fall.

No cropping pattern can be good for all times to come. But there is often a tendency for the cropping pattern to stabilize over a period of time in different agro-climatically homogeneous farming area. However, with the change in climate most prominent observation is the change in the length of growing season.

Thus to overcome the effect of climate change in the crops and receive the optimum benefits, cropping pattern has to be changed adaptation agriculture has to be adopted.

For example, changes in crop patterns are observed in West Bengal, India. To adapt to flooding and prolonged waterlogging, farmers are now practising fish farming with paddy cultivation. The rice-fish system is a polyculture practice that integrates rice cultivation with aquaculture. It provides benefits to the farmer from two production systems at the same time.

Farmers are also choosing crop combinations that provide more flexibility than a single crop. In Khulna, Bangladesh, farmers practice maize and garden pea intercropping systems in coastal areas. This has also resulted in better plant growth and yield in both crops.

ADAPTATION

Adaptation

Adaptation mainly aims to minimize peoples’ vulnerability by improving their ability to cope with the impacts of climate change. Adaptive capacity is often limited, particularly in poor rural areas where people live on subsistence agriculture. The communities have to be provided with climate change-related information and new adaptation strategies and measures have to be integrated into existing capacities, assets and resources. Understanding the climatic changes is necessary in order to adapt to the climatic changes. Information is required on short-term and long-term impact of climatic changes so that farmers can use different strategies and measures.

Covering vegetables with bamboo nets

With the change in temperature condition, incidence of pest and insect infestation also increases.
Vegetable fields are routinely devastated by insects and extended drought conditions.
Small holding farmers can combat this issue through simple technique of using bamboo net barriers.
Use of simple mosquito net with the available bamboo can manage insect pests and also maintain the micro-climatic conditions of that area of cultivable land.

Cultivating before rainy season

Adjustment of planting date or changing in cropping calendar is important to minimize the effect of temperature and sustaining the yield. Planting before rainy season will allow more effective use of soil moisture received from rainwater.

Mulching

Mulching is cultural practice often recommended in the cultivation of vegetables and mulch is a protective covering usually of leaves or straws placed around the plants. Spreading dry leaves over crops control the water losses due to transpiration.

Support for crops

Heavy and unpredicted rainfall, strong wind and other adverse weather condition could be resultant of expected climate change.
Simple and cultural way to save the standing crop from falling down due to heavy rainfall would be placing sticks for the support.

Salt stress control

The salinity of the soil is increasing in the coastal belts and is a major stress factor that affects crop growth in the area. Using salt-tolerant seed varieties enable farmers to farm profitably and productively.
For example, research institutes in both India and Bangladesh have developed salt-tolerant rice varieties for cultivation.

Integrated farming systems

In areas prone to floods and extreme weather events monocropping is generally practiced. In these vulnerable areas, dependence on single farm enterprises by farmers is risky as they have limited resilience to cope with climatic constraints.
Integrated farming systems approach involves use of outputs of one enterprise component as inputs for other related enterprises wherever feasible, for example, cattle dung mixed with crop residues and farm waste can be converted in to nutrient-rich vermi-compost.

CONSERVATION AGRICULTURE

CONSERVATION TILLAGE

Tillage aims to create a soil environment favorable to plant growth; however conservation tillage refers to disturbing the soil only where the seed, fertilizer and manure are to be placed. No tillage, minimum tillage, reduced tillage and mulch tillage are terms synonymous with conservation tillage.
Conservation Tillage:

Reduces destruction of the soil structure
Does not expose soil to wind and water erosion
Improves water infiltration rates
Slows the rate at which organic matter is mineralized and oxidized, so organic matter build-up occurs
Causes little disruption to the organisms that live in the soil
Saves time, energy, and money because less land is tilled
Reduces soil compaction because the crop plant roots are left undisturbed. Conservation Agriculture improves yields, praects soil, increases soil moisture and restores soil fertility. Conservation Agriculture reduces production cost cuts costs on labor and fertilizer while increasing their yields.

PERMANENT SOIL COVER

Soil is better protected from the physical Impact of water, wind and direct Insolation (exposure to the sun) when it is covered. Soil can be covered with previous-crop residues or cover crops, which also increases biomass. This farming practice is one of the best ways to turn agricultural land into carbon sink

Helps reduce direct raindrop impact and so reduces soil erosion
Helps reduce runoff and aids water to seep Into the soil
Reduces evaporation and conserves moisture for the crop
Suppresses weeds emergence
Organic residues improve organic matter content and soil nutrient status
Provides a beneficial environment for soil organisms, such as worms and millipedes, that are important for biological tillage
Moderates soil temperatures

INTER CROPING

Intercropping is the cultivation of two or more crops simultaneously on the same field. Either both the crops can be sown at the same time in the same field or the second crop could be sow after the first crop has completed its development.

There are four (4) sub-categories of intercropping:

Mixed Intercropping:
Growing two or more crops simultaneously with no district row arrangement. Example: Pumpkins, okra, cowpea and cucumber can be grown simultaneously on the same field with no distinct row arrangement.
Row intercropping:
Row intercropping is the growing of two or more crops at the same time with at least one crop planted in rows. When all the crops are grown in rows a specific ratio is maintained.
Example: Wheat and mustard, wheat and pea
Strip cropping:
Growing of two or more crops of different families at the same time in small portions arranged side by side. It is ideal for vegetables. The crops should be grown wide enough to permit separate crop production using machines but close enough for the crops to interact.
Example: Alternating strips of wheat, corn and soybean 6 rows wide each.
Relay Intercropping:
Planting a second crop into a standing crop at a time when the standing crop is at its reproductive stage but before harvesting.
Example: Intercropping soybean with ripened winter wheat

Advantages of intercropping

Replenishes soil fertility: intercropping with nitrogen-fixing legumes adds ‘top-dressing Fertilizer’ to the soil
Enables crops to use the nutrients in the soil more effectively
Helps to control weeds, diseases and pests by breaking their life cycles through the introduction of a new crop
Reduces the risk of total crop failure in case of drought and disease outbreak.
Reduces the plant diseases. The distance between plants of the same species is increased because other crops (belonging to a different family group) are planted in between.
Results in potential increase for total production and farm profitability than when the same crops are grown separately.
Provides 2 or more different food crops for the farm family in one cropping season.

CROP ROTATION

The system of varying successive crops in a definite order on the same ground is called a crop rotation. They involve changing the type of crop grown in one area on a regular basis.

Advantages of crop rotation

Crop rotations prevent the buildup of pests and diseases. When the crop is grown for successive years, the eggs of insects and disease-causing pathogen remain in the soil and keep flourishing. When the crop is changed every year, buildup of these pests can be avoided. As a result, it reduces reliance on synthetic chemicals
They help to maintain soil fertility. When a crop is grown for successive years same nutrients get used up and their content depletes. Crop rotation replenishes the soil nutrients.

AGRO-FORESTRY

Agroforestry refers to growing trees together with other agricultural crops and animals, with benefits to plants, animals, people, and the environment. It combines agricultural and forestry technologies to create more diverse, productive, profitable, healthy, and sustainable land-use systems.

The use of trees for soil conservation and sand dune stabilization has been achieving good results. These practices involve establishment of woodlots, protective hedges and live fences around homesteads and home gardens. Both food and non-food species of trees, including fodder tree species and trees for fuel wood and construction material, can be used. An agro-forestry system has the potential to fight the aberrations due to climate change.

The selection of appropriate agro-forestry systems is usually based on existing practices, climate, soil conditions, the level of soil erosion, livestock population, availability of pastures, household food supply and nutrition, and fuel wood requirements. Features of the areas to be taken care of include the increasing land degradation and decreasing carrying capacity of the land, increasing water logging.

Homestead gardens and orchards: This system involves the establishment of small orchards or the scattered planting of individual fruit trees in the home garden, inter-planted with various vegetables.

Shelterbelts: Also known as windbreak, a shelterbelt is a plantation made up of one or more rows of trees or shrubs planted in a manner to provide shelter from wind and protect soil from erosion. It help in increasing the soil moisture and also provides a safe barrier from farm animals.

Hedges and live fences: Trespassing is a huge problem in lowlands and it is advisable to establish protective hedges and live fences around the homesteads, especially against livestock kept within the village.

Fodder banks/trees on contour strips in cultivated area: This system is more applicable to the areas where grazing resources are poor. In arid and semi-arid lands, leaves and edible twigs of trees and shrubs can constitute well over 50 percent of the biomass production. Even in regions of higher rainfall where grass supplies the major portion of soil organic matter eaten by ruminants, tree leaves and fruits can form an important constituent of the diet, particularly for small ruminants. These trees could be planted in rows inter-cropped with herbaceous annual or perennial fodder crops.

Sand dune stabilization via trees and shrubs plantation: Planting suitable vegetation on sand dune surface results in decreasing surface wind speed, prevention of scouring action and improvement of soil conditions, which ultimately lead to improved micro-climatic condition of the area. Common dune vegetation include Ipomea pes-caprae or Chhagal kuri, Umbrella tree or Ketaki, Sea Purslane or Jadu palang, Whistling pine or Jhau, Spinifex littoreus or Nona durba.

CLIMATE CHANGE: HOW TO OVERCOME ITS IMPACT?