skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Measuring organic matter in Everglades wetlands and the Everglades Agricultural Area

Abstract

Here, organic matter is a complex material that represents the long-term decay products from plants and other organisms in the soil. When organic matter is allowed to build up in a soil, the soil color at the surface usually turns a darker color, often with a red or brown hue. Typically in Florida mineral soils, organic matter content is quite low, within the range of 1 to 5%. However, in some soils that remain flooded for most of the year, organic matter can build up with time and actually become the soil. Such is the case for the organic soils, or histosols, found in southern Florida. These organic soils comprise much of the Water Conservation Areas, Everglades National Park (ENP), Big Cypress Basin, and the Everglades Agricultural Area (EAA). It is important to document organic matter accumulation in the Everglades to gauge the effectiveness of wetland creation and succession. For the EAA, the drained soils lose organic matter due to oxidation, so measurement of the organic matter content of these soils over the course of time indicates the oxidation potential and mineral incorporation from bedrock. Due to the wide diversity of soil types and methods of measuring soil organic matter,more » there is a need to devise a more universal method applicable to many types of histosols in south Florida. The intent of this publication is: 1.To describe a simple laboratory method for determining the organic matter content of the organic soils of southern Florida and demonstrate the importance of using this new procedure for improved accuracy and precision; 2.To utilize this updated laboratory procedure for field sites across Everglades wetlands and the EAA; and 3. To recommend this procedure be used by growers, state and federal agencies, and university and agency researchers dealing with the management of organic soils in southern Florida. Growers can use this improvement to organic matter measurement to keep lab testing costs low while getting a better, more quantitative estimate of organic carbon (organic matter) for decisions regarding pesticide applications and estimated contribution of nutrients released from the organic matter in their fields. Restoration efforts in the Everglades wetlands can be better documented with the lower cost, but now equally as useful, LOI test for organic carbon. Improvements to soil organic matter coupled with other measurements of biological health of the system can be documented with less work using the adjusted LOI calculations.« less

Authors:
 [1];  [1]
  1. Univ. of Florida, Gainesville, FL (United States)
Publication Date:
Research Org.:
Intelligentsia International, LaBelle, FL (United States)
Sponsoring Org.:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Bioenergy Technologies Office (EE-3B)
OSTI Identifier:
1337331
Report Number(s):
DOE-HENDRYFLA-00303-203; EDIS-SL285
DOE Contract Number:
EE0000303
Resource Type:
Technical Report
Resource Relation:
Related Information: Electronic Data Information Source (EDIS) of UF/IFAS Extension, publication number SL285
Country of Publication:
United States
Language:
English
Subject:
54 ENVIRONMENTAL SCIENCES; organic matter; Everglades Wetlands; Everglades Agriculture Area; Southern Florida; land use; Histosols; CNS method; LOI method; organic carbon; organic matter accumulation; oxidation

Citation Formats

Wright, Alan L., and Hanlon, Edward A. Measuring organic matter in Everglades wetlands and the Everglades Agricultural Area. United States: N. p., 2015. Web. doi:10.2172/1337331.
Wright, Alan L., & Hanlon, Edward A. Measuring organic matter in Everglades wetlands and the Everglades Agricultural Area. United States. doi:10.2172/1337331.
Wright, Alan L., and Hanlon, Edward A. Thu . "Measuring organic matter in Everglades wetlands and the Everglades Agricultural Area". United States. doi:10.2172/1337331. https://www.osti.gov/servlets/purl/1337331.
@article{osti_1337331,
title = {Measuring organic matter in Everglades wetlands and the Everglades Agricultural Area},
author = {Wright, Alan L. and Hanlon, Edward A.},
abstractNote = {Here, organic matter is a complex material that represents the long-term decay products from plants and other organisms in the soil. When organic matter is allowed to build up in a soil, the soil color at the surface usually turns a darker color, often with a red or brown hue. Typically in Florida mineral soils, organic matter content is quite low, within the range of 1 to 5%. However, in some soils that remain flooded for most of the year, organic matter can build up with time and actually become the soil. Such is the case for the organic soils, or histosols, found in southern Florida. These organic soils comprise much of the Water Conservation Areas, Everglades National Park (ENP), Big Cypress Basin, and the Everglades Agricultural Area (EAA). It is important to document organic matter accumulation in the Everglades to gauge the effectiveness of wetland creation and succession. For the EAA, the drained soils lose organic matter due to oxidation, so measurement of the organic matter content of these soils over the course of time indicates the oxidation potential and mineral incorporation from bedrock. Due to the wide diversity of soil types and methods of measuring soil organic matter, there is a need to devise a more universal method applicable to many types of histosols in south Florida. The intent of this publication is: 1.To describe a simple laboratory method for determining the organic matter content of the organic soils of southern Florida and demonstrate the importance of using this new procedure for improved accuracy and precision; 2.To utilize this updated laboratory procedure for field sites across Everglades wetlands and the EAA; and 3. To recommend this procedure be used by growers, state and federal agencies, and university and agency researchers dealing with the management of organic soils in southern Florida. Growers can use this improvement to organic matter measurement to keep lab testing costs low while getting a better, more quantitative estimate of organic carbon (organic matter) for decisions regarding pesticide applications and estimated contribution of nutrients released from the organic matter in their fields. Restoration efforts in the Everglades wetlands can be better documented with the lower cost, but now equally as useful, LOI test for organic carbon. Improvements to soil organic matter coupled with other measurements of biological health of the system can be documented with less work using the adjusted LOI calculations.},
doi = {10.2172/1337331},
journal = {},
number = ,
volume = ,
place = {United States},
year = {Thu Jan 01 00:00:00 EST 2015},
month = {Thu Jan 01 00:00:00 EST 2015}
}

Technical Report:

Save / Share:
  • This publication pertains to management of organic soils (Histosols) in the Everglades Agricultural Area (EAA). These former wetland soils are a major resource for efficient agricultural production and are important globally for their high organic matter content. Recognition of global warming has led to considerable interest in soils as a repository for carbon. Soils rich in organic matter essentially sequester or retain carbon in the profile and can contribute directly to keeping that sequestered carbon from entering the atmosphere. Identification and utilization of management practices that minimize the loss of carbon from organic soils to the atmosphere can minimize effectsmore » on global warming and increase the longevity of subsiding Histosols for agricultural use. Understanding and predicting how these muck soils will respond to current and changing land uses will help to manage soil carbon. The objectives of this document are to: a. Discuss organic soil oxidation relative to storing or releasing carbon and nitrogen b. Evaluate effects of cultivation (compare structure for sugarcane vs. uncultivated soil) Based upon the findings from the land-use comparison (sugarcane or uncultivated), organic carbon was higher with cultivation in the lower depths. There is considerable potential for minimum tillage and residue management to further enhance carbon sequestration in the sugarcane system. Carbon sequestration is improved and soil subsidence is slowed with sugarcane production, and both of these are positive outcomes. Taking action to increase or maintain carbon sequestration appears to be appropriate but may introduce some risk to farming operations. Additional management methods are needed to reduce this risk. For both the longevity of these organic soils and from a global perspective, slowing subsidence through BMP implementation makes sense. Since these BMPs also have considerable societal benefit, it remains to be seen if society will help to offset a part or all of the additional risk through some form of cost-sharing program or carbon credits trading. In general, the subsidence throughout the EAA has been slowed because of higher water table management and implementation of other selected BMPs. In addition, the comparison of soil with different land uses shows that the humification rate, conversion of organic matter from peat to humus, has changed. Another likely factor is a relative increase in the mineral content of soil as the organic constituents are lost through subsidence.« less
  • Land use changes, agricultural drainage and conventional cultivation of winter vegetables and sugarcane cropping in the Everglades Agricultural Area (EAA) may alter soil conditions and organic matter decomposition and ultimately influence the fate of phosphorus (P). Theses agricultural practices promote soil subsidence, reduce the soil depth to bedrock limestone and increase the potential for incorporation of limestone into the root zone of crops. The incorporation of limestone into surface soil has significantly increased soil pH which in turns causes greater fixation of P fertilizer into unavailable forms for plant growth. Additional P fertilization is thus required to satisfy crop nutrientmore » requirements in plant-available P form. It is important to determine how the mixing of bedrock limestone into soils influences the behavior of P fertilizers after their application. To accomplish this task, P fertilizers were applied to (1) typical cultivated soils and to (2) soils that have never been fertilized or extensively tilled. The changes in P concentrations over time were then compared between the two land uses, with differences being attributable to the impacts of cultivation practices. The P distribution in soil varied between land uses, with sugarcane having more P in inorganic pools while the uncultivated soil had more in organic pools. Water-soluble P concentrations in soil increased with increasing fertilizer application rates for all sampling times and both land uses. However, concentrations in uncultivated soil increased proportionally to P-fertilized soil due to organic P mineralization. At all sampling times, plant-available P concentrations remained higher for uncultivated than sugarcane soil. Lower P concentrations for sugarcane were related to adsorption by mineral components (e.g. limestone). Cultivated soils have higher calcium concentrations resulting from incorporation of bedrock limestone into soil by tillage, which increased pH and fostered sequestration of plant-available P into stable calcium-bound P pools. This greater P retention for sugarcane was reflected in the greater proportion of P in inorganic pools compared to uncultivated soils. Some lands within the EAA, including wetlands and seasonally-flooded prairies, are being reclaimed for water quality purposes. However, long-term effects of fertilization and cropping practices described in this document indicate that direct conversion from active farming, such as from sugarcane production directly to wetlands, may be problematic due to the changes in nutrient dynamics that may occur. The shift directly to wetlands may, in fact, release considerable amounts of P into the Everglades, thwarting the intent of the land use change. The inorganic P component in sugarcane soils may lead to the regeneration of soluble P in frequently flooded land uses such as wetlands. While most of the inorganic P pools are unavailable to sugarcane, the direct conversion of sugarcane soils to wetlands may facilitate P release. Here, reclamation of sugarcane fields for environment uses would benefit by an intermediate step to allow for a short duration of seasonal flooding allowing for P conversion from inorganic to organic forms. Prolonged flooding of organic soils previously used for intensive agriculture is not recommended.« less
  • Numerous laboratory and field studies have shown that the chemical form (i.e., speciation) of many metals and radionuclides is affected by the presence of naturally occurring organic matter (OM) and its degradation products. The effects of OM (e.g., wood products) on the speciation and, therefore, the mobility of Am, Bk, Cf, Cm, Cs, Ni, NpO{sub 2}, Rb, Sr. UO{sub 2}, and Zr were estimated through use of geochemical and groundwater flow modeling. Due to the complex mixture nature of naturally occurring OM, the OM system was simplified through use of surrogate compounds (citric acid and ethylenedinitrilotetraacetic acid (EDTA)) to estimatemore » effects of OM on radionuclide mobility. Using this approach, OM was found to have no effect on the inventory limits for Cs, NpO{sub 2}, Rb and Zr. The inventory limits for the isotopes of Am, Bk, Cf, Cm, Ni, Pd, PuO{sub 2}, Sr, and UO{sub 2} calculated in the presence of OM decreased over a range of 26 percent for U-233 to 48 percent for Pu-240. The information in this report will be included in the next revision of the E-Area Vaults Performance Assessment.« less
  • Studies on mineral cycling in natural vegetation, with special reference to the cycling of the products of uranium fission, were carried out over a 5-year period on the bed of White Oak Lake after it was drained in 1955. The lake had been used for several years for the impoundment of both radioactive and domestic wastes froin Oak Ridge nuclear plants. A considerable body of detailed information on mineral cycling in natural vegetation was accumulated. Results are presented from studies on early succession and floristic changes on a relatively small area, and from the chemical analysis of about 40 speciesmore » of plants both in terms of chemical concentration and yield on an area basis. This information is related not only to the input or accumulation portions of the cycle, but also to the accumul.ation and decay of litter. Major chemical elements and radioactive contaminants at trace level are considered from the standpoint of the amount of material moved per year, the proportion of material moved per year, and number of years required for return to the soil of one year's material input. The data contribute to the understanding and elucidation of the metabolism of ecosystems and provide a basis for the intelligent management of radioactive wastes. (220 references.)« less
  • Most wetlands lost recently were converted for agricultural production. President Bush proposed 'No Net Loss' as a national goal, meaning that restoring wetlands must complement conserving wetlands to offset unavoidable losses. The symposium explored how 'no net loss' might operate and the economist's role in developing the policy. Wetland policy evolution, costs of acquiring public rights to wetlands, valuing wetland benefits, and alternatives to existing institutional mechanisms for controlling wetland loss were discussed.