SOIL SENSE: Let s Stop Treating Our Soils Like Dirt Our Lives Depend On It!

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1 SOIL SENSE: Let s Stop Treating Our Soils Like Dirt Our Lives Depend On It! New York State Turfgrass Association Southeast Regional Conference January 30, 2018 Dawn Pettinelli UConn Soil Nutrient Analysis Laboratory dawn.pettinelli@uconn.edu

2 WHAT IS SOIL? soil - (i) The unconsolidated mineral or organic material on the immediate surface of the Earth that serves as a natural medium for the growth of land plants. (old definition) From the Soil Science Glossary (Soil Science Society of America).

3 WHAT IS SOIL? soil The layer(s) of generally loose mineral and/or organic material that are affected by physical, chemical and/or biological processes at or near the planetary surface and usually holds liquids, gases, and biota and support plants. (new definition, 2017) From the Soil Science Glossary (Soil Science Society of America).

4 SOIL FORMATION

5 NEW ENGLAND SOILS In general, CT soils are stony, acidic, sandy loams Result of glaciation Areas of lakebed sediments and alluvial soils Shallow to bedrock Native soils in CT mostly low in P, Ca, CEC.

6 NATIVE SOIL GREAT FOR NATIVE PLANTS!

7 SOIL-PLANT SYSTEM From: Extension.org Relationships between plants & soils evolved over billions of years. For plant life to endure, needs nutrients. Micro-organisms evolved with plants to break down organic matter symbiotic relationships. Closed system. From: rmsiblog.wordpress.com

8 WELFARE OF SOIL-PLANT SYSTEM GOVERNED BY: 1. SOIL AIR 2. SOIL WATER 3. DECOMPOSITION 4. SOIL FERTILITY THESE FACTORS AFFECT & AFFECTED BY SFW!

9 From: From The Soil Up by Donald L. Schriefer SOIL AIR

10 OXYGEN IS ESSENTIAL! Plant root growth and extension, nutrient uptake, and biological activity are all directly related to the level of available oxygen in the soil. From: From The Soil Up by Donald L. Schriefer

11 SOIL WATER Water essential to all life processes. 100 to 2000 pounds of water needed to produce one pound of dry matter. Plants absorb nutrients with soil water. Plants are heavy drinkers!

12 RULES FOR MANAGING SOIL WATER From: From The Soil Up by Donald L. Schriefer

13 From: From The Soil Up by Donald L. Schriefer DECOMPOSITION

14 DECOMPOSITION 1. Don t lament the fact that organic matter is continuously being used and needs to be replaced it s Nature s Way. 2. Since more than just simple nutrients are released in the decay process and we know plants, soils and soil organisms co-evolved, we should encourage the natural decomposition process and use of the end products (compost!).

15 SOIL FOOD WEB Soil organisms decompose organic compounds. They store nutrients. They fix nitrogen from atmosphere. They enhance soil aggregation and porosity. Prey on crop pests. Food for those higher up in the food chain. SFW is community of organisms living all or part of their lives in the soil participate in series of conversions of energy and nutrients. From Soil Biology Primer, SWCS, USDA 2000

16 ESSENTIAL SOIL FOOD WEB FUNCTIONS 1. Sustaining biological activity, diversity and productivity. 2. Regulating flow of water and dissolved nutrients. 3. Storing and cycling of carbon, nitrogen and other elements. 4. Filtering, buffering, degrading, immobilizing and detoxifying organic and inorganic materials that are potential pollutants.

17 SOIL FERTILITY Soil Fertility is defined in terms of both soil nutrient levels and the ability of the plant to recover those nutrients. Soil conditions and cultivation can either favor or adversely affect nutrient release and uptake by the plant.

18 PLANT NUTRITION INORGANIC SIDE - Includes inorganic elements like Ca +2, NO 3-, Fe +3, etc. ORGANIC SIDE Includes enzymes, hormones, chelated elements, antibiotics, and other substances. Not as much known but doesn t mean less important.

19 SUSTAINABLE GARDENING PRACTICES A sustainable garden is based on ecologically-sound soil management practices which aim to maintain and replenish soil fertility by providing optimal conditions for soil biological activity. Modeled on natural ecosystems where diversity, complexity, and the recycling of energy and nutrients is essential.

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21 SOIL DESERVES RESPECT! Throughout history, ways societies used/abused their soil resources influenced their ultimate fates from Mesopotamia to Greece, Rome and beyond. Today, though we are so dependent on soil, we have become so detached from it. This breeds ignorance and out of ignorance comes the delusion that our civilization has risen above nature and has set itself free of nature s constraints!

22 SOIL SERVES US WELL! Ecological Functions 1. Biodiversity and habitat 2. Water relations 3. Nutrient cycling 4. Filtering and buffering 5. Physical stability and supporting man-made structures Economic/Social Functions 1. Crop/biomass production 2. Ag industries livestock, forestry 3. Source of raw materials iron, limestone, rare earth metals 4. Clay for bricks and arts 5. Clues to past archaeologists.

23 HOW MUCH SOIL SERVES US?

24 HOW MANY PEOPLE NEED TO BE FED, CLOTHED, SHELTERED? Now about 7.5 billion! Takes only about 13 years now to add another billion that s 80 million people added every year! By billion!

25 LAND DEGRADATION Land Degradation is the decline in land quality or reduction in its productivity caused by natural factors but more typically human activities. Important global issue! NEED PRODUCTIVE LAND TO PRODUCE FOOD!

26 TYPES OF LAND DEGRADATION Physical Chemical Biological Erosion Acidification Decrease Organic Matter (Biomass C) Deposition Salinization Decline in Biodiversity Compaction Leaching Gas Emissions (CO 2, CH 4, NOx) Desertification Fertility Depletion Eutrophication Anaerobism General Decline in Soil Structure Environmental Pollution Decrease in CEC Ground Water Contamination Land degradation is a biogeochemical process driven mainly by socioeconomic and political decisions!

27 EROSION Water & wind carry soil into streams, lakes, ocean, sewers. With soil comes pollutants - oil, fertilizers, pesticides & other chemicals, animal manures, bacteria all threaten water quality. Loss of topsoil, minerals, nutrients: productivity. Destroys wildlife habitats, recreation areas. $ costs to homeowners, local governments, businesses, federal governments. Estimates up to 75 billion tons soil lost/yr and costs $400 billion/yr!

28 THE GREAT DEBATE Economists/Politicians say land degradation processes not severe enough to implement action plans on national or international level and farmers should maintain soils since they derived benefits of it. Soil Scientists/Agronomists say land is a non-renewable resource (human time scale). Ag can t be viewed as just another business because economic benefits of soil conservation only harvested after decades of stewardship.

29 THE GREAT DEBATE Soil Scientists/Agronomists also say some of the adverse effects of land degradation processes, like the reduction in rooting depths due to erosion of topsoil, are irreversible, and improved technologies whether GE crops, new machinery, pesticides, and the like, only serve as a band-aid approach, give us a false sense of security. and fail to address the real problem that will one day catch up with us we need to maintain healthy, productive soils to supply the needs of our civilization!

30 SOILS AND CLIMATE CHANGE Soils affected by and contribute to climate change. Soils store C as organic matter. As temperatures rise, more decomposition so CO 2 released. More decomposition, nutrients released faster than can be taken up loss of fertility. Increased salinization. As violent storms/floods occur more frequently more erosion. Forest fires. Increased desertification. Waterlogged/flooded soils methane produced

31 KEY TO SUSTAINABLE SOILS? Conventional, industrial farmers sacrifice soils to maximize short-term returns for profits and to pay for rent, machines, pesticides, fertilizers, etc. Subsistence farmers mine soil because they are trapped in plots too small to feed their families. WHAT S THE WORLD TO DO? EDUCATION AGRICULTURE REFORMS SUPPORT LOCAL FARMERS

32 We are of the soil. And the soil is of us, for we too are dependent on it for life, and we return ourselves to it in death We must not be indifferent to our land for it is the hand that feeds us. -Chuck Pendergast, Introduction to Organic Gardening

33 Thanks! Any Questions?