Soil and Agriculture:Land Degradation and Soil Conservation

By: Shaiza Ali, Simran Chotrani, Tyng Pan, Mansi Patel November 18, 2013

AP Environmental ScienceMs. Yuhas

Desertification reduces productivity of arid lands

• Dry lands – arid and semi-arid environments that cover about 40% of Earth’s land service

• Desertification – a form of land degradation in which more than 10% of productivity is lost

• Made worse by climate change

Fertile Crescent region

Desertification reduces productivity of arid lands

• Causes: erosion, soil compaction, forest removal, overgrazing, drought, salivation, climate change, water depletion

• Effects: endangers food supply, dust storms

41.80%

45.20%

3.40%

9.70%

Causes of soil degradation

Wind erosionWater erosionSoil structure problemsChemical prob-lems

The Dust Bowl was a monumental event in the United States.

• The US, specifically the Great Plains, was once a land that supported prairie grasses that held soils in place.

• Settlement in 19th and early 20th centuries- area was turned into farmland.

• Land was unsuitable to grow crops and graze cattle. • This contributed to soil erosion by removing native

grasses and altering soil structure.

Dust Bowl Region

The Dust Bowl was a monumental event in the United States.

• The most affected region in the Southern Great Plains become known as the Dust Bowl.

• The area was subject to “black blizzards” – massive gusts of dust that clouded the air.

• This, combined with drought, forced people off the land.

Kansas dust storm, 1930s

The Soil Conservation Service pioneered measures to address soil degradation.

Soil Conservation Act of 1935, establishing the Soil Conservation Service (SCS). This new agency works to: • Assess the land’s resources, problems, and

opportunities for conservation. • Prepare an integrated plan for each property• Work closely with land users • Implement conservation measures

The Soil Conservation Service pioneered measures to address soil degradation.

- Conservation districts: operate with federal direction, authorization, and funding, ut they are organized by the states. - 1994, SCS renamed to Natural Resources ConservationService (NRCS) responsibilites expanded to include water quality

protection and pollution control

Soil conservation efforts are thriving internationally.

• The SCS and NRCS serve as models for the world.• For example, parts of South America, such as

Argentina, have shifted to no-till farming. • This happened due to the efforts of local grassroots

organizations and information provided by the government.

No-till farming

Soil Conservation Efforts are Thriving Internationally

• Other approaches to soil conservation include:– Crop rotation– Contour farming– Strip cropping– Terracing– Grazing management– Reforestation– Wildlife management

Contour Farming

Case Study: Measuring Erosion with Pins and … Nuclear Fallout?

• Late Jerry Ritchie, had adopted low and high tech methods by using simple measuring pins and turning them into radiation detectors.

• In order to see if these “erosion” pins would work, they were used to measure erosion around hedges near gullies in Maryland.

• Using these pins over wide areas gave an average reading of overall erosion rate.

Case Study: Measuring Erosion with Pins and … Nuclear Fallout?

• The pins used in Maryland, using these technique, they found that 1-2 cm soil accumulating upslope from the hedges

• In order to get evidence of erosion on a wider scale, scientist have considered measuring nuclear fallout.

• Fallouts include cesium-137, a radioactive isotope of the cesium element.

• Radioactive test helped Ritchie determine that hedges can only offer partial help against erosion.

Current Events - Healthy soil: the basis for a strong economy and wholesome

environment• Soil not only holds environmental and agricultural

importance; it is vital to ensuring the growth of a healthy economy.

• This is why an EU-funded project aims to show how successful regenerative agricultural practices for preventing soil degradation can make a significant difference.

• Soil offers us many services, including acting as a filter and buffer to contaminants, allowing us to have clean drinking water. It also acts as a pool of biodiversity, and as a sink for atmospheric carbon dioxide.

Current Events - Healthy soil: the basis for a strong economy and wholesome

environment• However, soil has been subject to urbanization, mal-

farming, pollution, and climate change, leading to its degradation.

• This is why the LIFE REGEN FARMING project was launched in July 2013: in an attempt to discover and develop regenerative practices for soil conservation.

• These practices include the use of crops with minimum tillage, perennial crops, organic fertilizers, direct seeding and rotational grazing.

Current Events - Healthy soil: the basis for a strong economy and wholesome

environment

• The project has been awarded 700,000 euros to fund its research.

• The project has started its research in the meadows of rural Spain and hopes to complete all its testing in multiple areas by June 2016.

Bibliography • Google Images• Withgott, J., & Brennan, S. (2011). Essential

environment: the science behind the stories (4th ed.). San Francisco: Pearson.

• Tecnalia, N. (2013, October 29). European Commission : CORDIS : Newsroom. European Commission : CORDIS : Newsroom. Retrieved November 18, 2013, from http://www.cordis.europa.eu/fetch?CALLER=EN_NEWS&ACTION=D&RCN=36199