How humic acid improves saline-alkali soil

Humic acid gives strong help for saline-alkali soil. You can see the soil get better quickly. The pH level goes down. The soil structure also gets better after you use this amendment. Your crops grow more, take in more nutrients, and give a bigger harvest. The table below shows clear changes in soil and crop results when you use humic acid:

Farmers in the Yellow River Irrigation District got 18.32% more crops with humic acid. This shows humic acid helps crops grow and makes soil better for a long time.

Key Takeaways

• Humic acid helps saline-alkali soil by lowering pH. It makes soil structure better and helps crops grow more. High salt and alkalinity hurt plants by stopping water and nutrients from getting in. Humic acid helps fix these problems. Humic acid adds more organic matter to soil. It helps soil stick together, so roots grow better and hold water. It keeps nitrogen stable and helps plants use phosphorus. Plants get more nutrients and grow stronger. Humic acid helps good microbes live in the soil. These microbes make soil healthier and help plants fight salt stress. Using humic acid with gypsum, biochar, or vermicompost works even better. This gives better soil and more crops. Farmers get bigger harvests and use water better. They also save money by using humic acid on salty soils. Putting humic acid before or early in crop growth helps roots take in water and nutrients fast.

Saline-Alkali Soil Issues

High Salinity

Saline-alkali soil often has too much salt. This happens when salts like NaCl and Na2SO4 build up. These salts get inside plant cells and cause problems. Plants have trouble taking in water, even if the soil looks wet. This is called osmotic stress. The high salt pulls water out of roots. This makes plants act like they are in a drought.

If salt in the root zone goes over 3 g/kg, crops grow slower. If it is more than 10 g/kg, plants may stop growing. The table below shows how different salt levels affect crops:

High salt also causes ion toxicity. Too much sodium pushes out potassium. This leads to potassium deficiency. You might see yellow leaves and small plants. Over time, salt stress hurts chlorophyll and cell walls. This makes photosynthesis work less well.

Alkalinity

Alkalinity is another big problem in saline-alkali soil. When soil pH is above 8.5, plants get less iron, zinc, and manganese. High pH changes how nutrients move and how roots take them in. Roots cannot absorb cations as well. Plants then show signs of missing nutrients.

You might notice these problems:

• Yellow areas between leaf veins (interveinal chlorosis)

• Plants do not grow tall

• Crops do not yield much

Phosphorus becomes hard for plants to use. Potassium and nitrogen are also harder to take up. Most crops grow best when pH is 6.0 to 7.0. If pH is too high, plants get sick more and grow weak. Testing soil pH helps you find these issues early.

Poor Structure

Saline-alkali soil often has bad structure. High salt and sodium make soil particles swell and break apart. This causes:

• Soil clumps break down

• Hard, packed layers form

• Water does not soak in well

• Air cannot move in the root zone

Water may stay on top or run off fast. Roots have trouble growing in hard soil. When soil structure breaks down, organic matter and nutrients are lost. These changes make it hard for crops to grow and for you to fix salty soil.

Tip: Adding organic amendments can help fix soil structure. This helps water and air move better, so saline-alkali soil can grow more crops.

Low Fertility

Low fertility is a big problem in saline-alkali soil. It is not just about missing nutrients. High sodium and bad soil structure make things worse. Plants cannot get enough water or nutrients. You might see short plants or yellow leaves. This often means the soil is not fertile.

You can spot low fertility in many ways:

When sodium builds up, it pushes out calcium and potassium. Roots cannot take in what they need. This makes plants weak and harvests small. Hard soil stops roots from growing deep or wide. Water cannot move well, so plants get too dry and miss nutrients at the same time.

Your crops may not grow tall or make much food. Roots look thin and weak. Leaves may look pale or show missing nutrients. These signs mean the soil cannot help plants grow strong.

You can fix these problems with the right amendments. Adding organic matter like cow manure helps the soil hold more water and nutrients. This helps roots take in more of what they need. Gypsum gives calcium, which pushes out sodium and makes the soil better. These steps help bring back fertility and raise yields.

Here is a table that shows common soil problems and how to fix them:

Note: Using organic matter can raise soil nutrients and crop yield by 30-50%. This is a big help for fields with saline-alkali soil.

If you want better crops, work on making the soil more fertile. Good soil helps roots grow strong and use water better. This means you get more crops and your farm does better over time.

Humic Acid Overview

What Is Humic Acid

You might ask what humic acid is and why it helps soil. Humic acid forms when plants and microbes break down over time. You can find it in soil, compost, alginite, and lignite. Some products use marine plant extracts for more minerals and sugars.

Humic acid has many chemical parts. It has hydroxyl and carboxyl groups, aliphatic and aromatic structures, peptides, polyphenols, lipids, and polysaccharides. These parts help humic acid make soil better. When you add compost or manure, you put humic acid-like pieces into the soil. These pieces can have more proteins, sulfur, and sugars than what is in normal soil. How much the material breaks down depends on where it comes from. Compost humic acid usually breaks down more than manure or sludge.

Note: Where humic acid comes from changes how it works in soil. Some types help plants get more nutrients and help microbes grow better.

Key Properties

Humic acid is special because of its helpful properties. These properties help fix many soil problems, especially in saline-alkali soils.

• Active Functional Groups: Humic acid has phenolic hydroxyl and carboxyl groups. These make it safe for the environment.

• High Cation Exchange Capacity: It holds and swaps nutrients. This helps plants get what they need.

• Chelation Ability: Humic acid grabs metal cations. This helps roots take in important nutrients.

• Soil Structure Improvement: It helps soil clump together. This makes soil loose and holds more water.

• pH Neutralization: Humic acid helps balance soil pH. This makes soil less acidic or less alkaline.

• Enzyme Activity Boost: It makes soil enzymes work better. These enzymes help break down nutrients for plants.

• Colloidal Complex Formation: Humic acid forms complexes with soil minerals. This makes soil crumbly and easy to work.

• Water Management: Humic acid holds water on the soil surface. This stops cracks and keeps soil from washing away.

Here is a table that shows the main properties of humic acid and how they help soil and plants:

Tip: Humic acid works in many ways—physical, chemical, and biological. This makes it better than things like gypsum that only work one way.

You can see that humic acid is a strong tool for making soil healthier, especially when soil has too much salt or alkali.

Humic Acid and Soil Improvement

Organic Matter Increase

Humic acid helps soil get more organic matter. This is good for saline-alkali soils in many ways:

• Humic acid sticks small soil pieces together. These bigger clumps are called macroaggregates.

• Macroaggregates keep organic matter from breaking down fast. Saline-alkali soils lose organic matter quickly because they have poor structure.

• Adding humic acid puts more organic matter into these clumps. This makes the soil have more holes for water and nutrients to move.

• Good clumps make tiny homes for microbes. Microbes help recycle nutrients and add more organic matter.

• Humic acid helps good microbes and those that cycle nitrogen. This makes the soil richer and keeps organic matter steady.

• Better soil from humic acid stops nitrogen from being lost. More nitrogen stays for plants, so organic matter can build up.

When you raise organic matter, the soil gets healthier and grows more plants. This means you get better crops and bigger harvests.

Soil Structure Enhancement

Humic acid makes soil structure better and easier for roots. Studies show humic acid is strong at sticking soil together. It makes clumps that do not fall apart in water, especially with hydrogen or calcium. The chemical groups in humic acid help glue soil pieces. This glue makes the soil crumbly and loose, so roots can grow well.

Humic acid also covers clay with thin layers. These layers help hold clumps together. Microbes work with humic acid to make soil structure even better. Research says humic acid can make big clumps grow by up to 125%. This helps plants get more nutrients and take them up easier. Humic acid also helps soil fight being packed down or washed away. Better soil lets water and air move, which helps roots stay healthy.

You also get more enzyme activity in the soil. Humic acid boosts enzymes like urease, sucrase, and phosphatase. These enzymes break down nutrients for plants to use. The soil gets stronger and can keep growing crops for a long time.

Water Retention

Humic acid helps soil hold more water in salty soils. This means the soil keeps water longer, even when it is dry. Studies show humic acid helps crops like maize use water better. When you add humic acid, soil makes better clumps. These clumps have more spaces for water to stay.

Humic acid also helps soil hold more water and nutrients. It does this by raising cation exchange capacity. The acid groups in humic acid lower soil alkalinity. This stops salt from building up and keeps water from moving up and drying out. Less salt stays on top, so plants have less stress.

You will see the soil stays wet longer after rain or watering. This helps crops live through dry times and need less water. When soil holds more water, plants grow better and give bigger harvests in salty soils.

Tip: For best results, use humic acid with other soil fixes. This makes soil even better and helps crops grow more.

Humic Acid and pH Reduction

Neutralizing Alkalinity

Saline-alkali soils often have high pH. This makes it hard for plants to get nutrients. Humic acid can help lower the soil pH. When you use humic acid, the soil becomes better for crops. Studies show humic acid can drop pH in salty, alkaline fields. This happens because humic acid does many things in the soil.

Here is a table that shows how humic acid helps lower alkalinity:

Humic acid helps soil have more nutrients like nitrogen, phosphorus, potassium, iron, and zinc. These nutrients help crops grow strong. The soil gets healthier and gives better harvests over time.

Tip: Humic acid is a safe way to fix alkaline soil. It helps your plants and makes the soil better for future crops.

Buffering Effect

Plants need steady soil pH to grow well. Humic acid helps keep soil pH stable. This means the soil does not change pH quickly, even if you add acids or bases. The carboxyl and phenolic groups in humic acid do this job. They take in protons when pH drops and let them go when pH rises.

Adding humic acid makes the soil better at holding its pH. This keeps the root area safe and helps plants get nutrients. Studies show humic acid works best as a buffer between pH 5.5 and 8.0. The strongest effect is at pH 6.0. Most crops like this range.

The buffering effect gives you these good things:

• Less chance of missing or toxic nutrients

• Roots grow better in steady soil

• Soil stays fertile for a long time

Note: Humic acid is better at stopping high pH than low pH. This makes it great for salty, alkaline soils.

Using humic acid keeps soil pH steady. Your crops stay healthy year after year.

Nutrient Availability with Humic Acid

Nitrogen Stabilization

Humic acid helps keep nitrogen in salty soils. Nitrogen can leave the soil by washing away or turning into gas. This makes it hard for crops to get enough food. Humic acid makes the soil better and helps good microbes grow. The soil gets more clumps that hold nitrogen in place. This stops nitrogen from leaving the soil.

Here is a table that shows how humic acid helps with nitrogen:

Plants grow better and you waste less fertilizer. This means crops use more of the nitrogen you add.

Phosphorus Activation

Phosphorus can get stuck in salty soils. Plants cannot use it when it is trapped in hard rocks. Humic acid helps unlock phosphorus for plants. It grabs metal ions that would trap phosphorus. This keeps phosphorus easy for crops to use.

• Humic acid breaks up hard phosphate rocks so phosphorus can move.

• It makes new mixes with metals and phosphate, so plants can use more phosphorus.

• When you use humic acid with phosphate fertilizer, more phosphorus dissolves in water.

• The acids in humic acid fight with phosphate for metals, freeing up phosphorus.

• Humic acid also helps roots grow and take in more food.

Tests show humic acid with fertilizer helps crops use more phosphorus. Even a little humic acid in fertilizer helps a lot. Plants get healthier and you get bigger harvests because crops can use more phosphorus.

Chelation of Metals

Salty soils can have too much or too little metal. This can hurt crops. Humic acid helps by grabbing these metals. Its special groups stick to metals and keep them safe for plants. This makes metals easy for crops to use but not harmful.

When you use humic acid, crops get more iron, zinc, and manganese. It also keeps plants safe from too much metal. Humic acid helps plants fight stress and stay healthy. This means crops can grow well even in salty soils.

Tip: Humic acid not only helps plants get more food, but also helps them stay strong and grow better in tough soils.

Microbial and Environmental Effects

Microbial Community Regulation

Adding humic acid to saline-alkali soil helps microbes live better. These tiny living things need food and nutrients to grow. Humic acid gives them more of both. This makes more kinds of microbes live in the soil. The soil gets full of life and activity. Microbes break down old plant parts and recycle nutrients. They help plants grow stronger and healthier. When soil has better structure and more nutrients, more types of microbes can live there. This helps the soil get over salt problems faster. You also get more enzymes in the soil. These enzymes help plants get nutrients quickly. Using humic acid with things like vermicompost helps even more good microbes grow.

Salt Leaching

Saline-alkali soils often keep salt near the top. This hurts plant roots and stops them from growing well. Humic acid helps move salt away from the roots. Here is how it works:

• Humic acid makes soil clump together, so water moves better.

• Water can wash salt deeper into the ground, away from roots.

• The soil holds more water and stays wet for longer.

• Roots let out more carbon and nitrogen, feeding the microbes.

• More healthy microbes keep the soil working well.

If you use humic acid with gypsum or bentonite, you get even better results. Tests show this mix can cut soil salt by up to 35%. It can also lower bad sodium by over 60%. Plants can fight salt stress better and stay healthy. Their antioxidant systems work harder. This means crops grow better, even when the soil is tough.

Environmental Benefits

Using humic acid in salty soil helps the environment in many ways. It lowers salt in the soil and makes nutrients easier for plants to use. Field tests show humic acid cuts bad salts and changes nitrogen so plants can use it. The soil holds more water and does not dry out fast. This helps crops use water better. Humic acid stops salty water from moving up in the soil. This keeps plant roots safe. It also makes calcium and magnesium easier for crops to take in. Over time, the soil pH drops from very high to almost normal. This is better for most plants. These changes help farmers grow more crops and spend less money. You help the earth and get better harvests at the same time.

Tip: If you use humic acid on salty soil, you help your farm and the planet. The soil gets healthier, crops grow stronger, and the earth stays safe for the future.

Yield and Crop Yield Results

Plant Growth Improvement

When you put humic acid on saline-alkali soil, plants grow better. Roots get longer and stronger. Stems are thicker and leaves look greener. Plants stand up straighter and have more leaves. Humic acid helps soil keep more water and nutrients. The soil gets softer, so roots can spread out. This helps plants take in what they need.

Tests in fields and labs show humic acid helps maize grow taller. It also gives plants more leaf area. Crops have more dry matter above the ground. This means plants have more energy to grow. The table below shows how humic acid changes plant and soil traits:

Humic acid helps soil and every part of plant growth. Using about 193.5 kg per hectare gives the best water use. Plants use water better and grow strong, even in hard soils.

Crop Yield Increase

Farmers care most about how much crop they get. Humic acid gives a big boost to crop yield in salty soils. Crops grow taller, have more leaves, and make more grain or fruit. Humic acid helps roots take up more water and nutrients. It also lowers salt stress, so plants can focus on growing.

Check the table below to see how rice yield goes up with humic acid:

If you use 3000 kg per hectare of bio-humic acid, rice yield jumps to 9885 kg per hectare. Without it, you only get 393 kg per hectare. This is a huge difference. Other crops like maize and wheat also do better. Humic acid helps you get more food from the same land. This is important for farming that lasts.

You also see better water use and more dry matter above ground. Crops use what they have better and give higher yields. If you want more rice or maize, humic acid is a good way to help.

Economic Impact

Using humic acid in salty soils saves money and brings more profit. You spend less on watering because soil keeps water longer. You also save on fertilizer, since humic acid helps plants use nutrients. Healthier plants mean you use less pesticide and get better crops.

Here are ways humic acid helps your farm make more money:

• You pay less for water because soil stays moist.

• You use less fertilizer since plants get more nutrients.

• You get more crops and better quality, so you earn more.

• You spend less fixing soil later, as humic acid keeps soil healthy.

• You can grow valuable crops, like Olea europaea, even in salty soils.

• You see better plant growth and more plant material, so you make more per acre.

• You help the land stay good for future farming.

Note: Mixing humic acid with things like biochar makes soil and crops even better. This helps you build a strong and lasting farm.

Farmers who use humic acid say they make more money and get steady harvests. You can trust humic acid to boost your yield and help your crops grow. These good habits help you keep your land healthy and stay ahead for years.

Combined Applications

With Gypsum

You get more from humic acid if you use it with gypsum. This mix is good for fixing saline-alkali soil. Gypsum puts calcium in the soil. Calcium helps remove sodium, which makes soil hard and raises pH. Using both together works better than using one alone. Humic acid makes soil softer and helps it hold water. Gypsum cuts down sodium and helps keep soil balanced.

Here are some main benefits when you use both:

• Soil gets better faster and is easier to work.

• Water moves through soil better, so roots grow deeper.

• Soil keeps more nutrients and loses less from water washing them away.

• Crops have less salt stress and grow stronger.

Tip: Put gypsum on first to add calcium. Then use humic acid to help soil get better and use nutrients. This way, your field grows more and stays healthy.

With Biochar or Vermicompost

Mixing humic acid with biochar or vermicompost helps even more. Biochar helps soil keep water and nutrients. Vermicompost adds organic matter and good microbes. When you use these with humic acid, you make soil much better.

A study showed that using humic acid, biochar, and vermicompost together made cotton grow a lot. Plants got 39.2% taller. Stems were 36% thicker. Leaf area went up by 88.1%. Photosynthesis rose by 43.9%. Stomatal conductance almost doubled. Plants had more chlorophyll and grew more. Yield went up by 31.8%. This means crops grow faster, look better, and give more food.

Field tests found biochar alone helped soil hold 63.4% more water. It also raised organic carbon and cation exchange capacity. When you mix biochar with humic acid or vermicompost, salty soil gets better faster. This mix gives you richer soil and more crops.

Here is a table that shows how these mixes help:

Note: For best results, use 120 kg/ha humic acid, 60 kg/ha biochar, and 120 kg/ha vermicompost. This mix makes soil healthier and crops stronger.

You can make soil better and get more crops fast by using humic acid in salty, alkaline fields. If you use 3000 kg/ha of bio-humic acid, the soil pH drops. The soil gets more organic matter, calcium, and magnesium. This can help you grow up to 9750 kg of rice per hectare. You can plant and harvest in the same year. This helps you farm in a way that lasts a long time. Experts say you should mix humic acid with things like vermicompost or biochar. This makes soil even better and gives you more crops.

• Try mixing humic acid with other soil fixes for better crops and soil.

• Learn how humic acid works with fertilizers to help plants grow more.

• Think about your local soil and weather to keep soil healthy for many years.

Picking humic acid means you help your soil, get more crops, and make your farm strong for the future.

FAQ

What is the best time to apply humic acid to saline-alkali soil?

It is best to use humic acid before you plant. You can also use it when crops are just starting to grow. This helps roots get food and water right away.

Can you use humic acid with chemical fertilizers?

Yes, you can mix humic acid with most fertilizers. This helps plants use more nutrients and lose less fertilizer. Always check if your products work well together.

How often should you apply humic acid?

Use humic acid once or twice each growing season. If your soil is very poor, you might need to use it more often. Always follow the directions on the package.

Does humic acid work for all crops?

Humic acid helps most crops like grains, vegetables, and fruit trees. You will see plants grow stronger and give more food in many cases.

Is humic acid safe for the environment?

Yes, humic acid is natural and safe to use. It makes soil better without hurting good bugs or polluting water.

How long does it take to see results after using humic acid?

You might see better soil and plant growth in a few weeks. Bigger changes, like more crops, usually happen after one or two seasons.

Can you combine humic acid with gypsum or biochar?

Yes, you can use humic acid with gypsum, biochar, or vermicompost. These mixes make soil hold more water and nutrients and help plants even more.

What is the recommended application rate for humic acid?

Most experts say to use 100–300 kg per hectare for field crops. Always read and follow the label for the best results.

See Also

The Role Of Humic Substances In Enhancing Soil And Plants

Improving Pond Water Quality Using Sodium Humate Effectively

Discovering Plants That Thrive Best With Humic Acid

Comparing Sodium Humate And Additives For Aquaculture Success

Humic Acid Versus Chemical Fertilizers For Sustainable Farming