S. H. Daroub

• PHD
• Professor (Full) at University of Florida

Soil represents the largest reservoir of Archaea on Earth. Present-day archaeal diversity in soils globally is dominated by members of the class Nitrososphaeria. The evolutionary radiation of this class is thought to reflect adaptations to a wide range of temperatures, pH, and other environmental conditions. However, the mechanisms that govern comp...

The West Palm Beach‐C51 (WPB‐C51) canal connects Lake Okeechobee with Lake Worth Lagoon (LWL) in South Florida. This canal receives discharges from Lake Okeechobee and from agricultural and urbanized areas. The objectives of this research were to determine spatial and temporal differences and trends of N and P forms along the WPB‐C51 canal and LWL...

Sugarcane production in Florida occurs mainly in artificially drained Histosols of the Everglades Agricultural Area (EAA). Nowadays, the nitrogen (N) mineralization of these soils is the main source of N to the plants, however, depending on environmental conditions and the restricted soil depth of these organic soils, N availability might be limite...

Farms in the Everglades Agricultural Area in South Florida implement best management practices (BMPs) to reduce off farm phosphorus (P) discharges. Although all farms implement BMPs in a similar manner, there are differences in their performance regarding controlling of P discharges. The objective of this research was to determine differences in so...

Nitrification is a central process in the global nitrogen cycle, carried out by a complex network of ammonia-oxidizing archaea (AOA), ammonia-oxidizing bacteria (AOB), complete ammonia-oxidizing (comammox) bacteria, and nitrite-oxidizing bacteria (NOB). Nitrification is responsible for significant nitrogen leaching and N2O emissions and thought to...

Soil subsidence of peatlands occurs worldwide due to drainage. The Everglades Agricultural Area (EAA), located in South Florida, has been drained for agriculture since 1914, with subsidence resulting in shallow soils in certain areas. The purpose of this study is to determine the impact of water management strategies on soil oxidation and N release...

Peatlands store a significant portion of the global carbon (C) budget. Peatland drainage triggers soil subsidence and is a threat to soil conservation. Differences in C composition as soils get shallower in drained peatlands are not clearly understood. Soil C quality has been considered as one of the possible causes for changes in soil subsidence r...

In 2012, an estimated 50% of rural households in India had a system of drainage for moving wastewater away from their homes, but 0.0% have access to safe, reuseable, treated wastewater. Constructed wetlands can provide decentralized wastewater treatment for rural villages and lead to multiple benefits, such as reusable water, reduced disease, and d...

Constructed Wetlands (CWs) are a low-cost technology relying on natural processes to treat wastewater and provide a decentralized wastewater treatment option in communities with limited infrastructure. Little is known about their long-term maintenance or monitoring, or the experience of communities who adopt and maintain CWs. This research uses men...

The soils of the Everglades Agricultural Area (EAA) are mainly organic soils (Histosols), and their artificial drainage promoted aeration and resulted in soil subsidence. Sugarcane (Saccharum spp.) nitrogen (N) requirement has been fulfilled historically by organic matter mineralization, so very shallow soils could be limiting N availability for th...

Sustainable production in the Everglades Agricultural Area (EAA) is confounded by decreasing soil depth and high annual rainfall. Formerly a sawgrass marsh, Histosols predominate much of the EAA and these soils have frequently flooded following their drainage in the early 20th century. Subsidence has increased inundation frequency as soil depth has...

The purpose of this document is to outline the process of soil testing as an important tool for both fertilizer recommendations and as a BMP in this region. This EDIS article is one in a series which attempts to explain in easily understandable terms the implementation methods and rationale behind the main P load reducing BMPs employed on EAA farms...

This EDIS document is one in a series of publications that provide current implementation guidelines for commonly employed BMPs that target the reduction of P loads leaving EAA farms via drainage water. This document is SL-232, a fact sheet of the Soil and Water Science Department, UF/IFAS Extension. Original publication date January 2006.

Phosphorus fertilizer spill prevention is a Best Management Practice (BMP) approved by the South Florida Water Management District (SFWMD), one designed to reduce drainage P loads in the Everglades Agricultural Area (EAA). Spill prevention of P fertilizers is a BMP that is widely implemented by growers in the EAA. This BMP is easily implemented and...

Sugarcane production of the Everglades Agricultural Area (EAA) occurs mainly in organic soils (Histosols). Even though drainage of these natural wetland soils allowed crop production, it also modified the dynamics of the soil microbiota. Consequently, the soil presents increased microbiological oxidation, what results in soil subsidence. Thus, soil...

Sugarcane is the dominant crop produced in the EAA, due to the crop adaptability to the environmental conditions, the water table depth and soil moisture in the region. The soils of the EAA are mainly organic soils, located South of Lake Okeechobee, in an artificially drained area. The drainage of these soils resulted in soil subsidence, and conseq...

Integrated nutrient management systems that use a holistic approach, using inorganic fertilizers as well as management practices aimed to increase soil organic matter, are needed to improve soil health. Management practices need to take into account differences in soil properties, climate and available local resources. In this chapter, we discuss t...

Agricultural by-products applied as soil amendments have the potential to improve crop production on low organic matter (OM) soils. This two-year study investigated the use of two readily available sugarcane (Saccharum spp.) milling by-products, mill mud, and mill ash, as soil amendments to improve first sugarcane crop (plant cane) and subsequent c...

The addition of organic residues to sand soils can improve soil properties and sugarcane productivity. However, biochar use can have variable effects on crops, and few studies have evaluated the effect of mill ash applications on sand soils. This study aimed to determine the effect of mill ash, and three biochars on yields of sugarcane grown on san...

Agricultural development during the Green Revolution brought India food sovereignty but food insecurity persists. Increased crop production was promoted without considering the more holistic impact on food security. Scientists, extension agents, and farmers have different perspectives on how soil health relates to food security. Understanding stake...

The purpose of this study is to describe the methods used to capture flow-weighted water and suspended particulates from farm canals during drainage discharge events. Farm canals can be enriched by nutrients such as phosphorus (P) that are susceptible to transport. Phosphorus in the form of suspended particulates can significantly contribute to the...

PurposeThe purpose of this study was to evaluate the influence of suspended particulates on P loading captured during a single storm event. The Everglades Agricultural Area of Florida comprises 280,000 ha of organic soil farmland artificially drained by ditches, canals, and pumps. Phosphorus (P)-enriched suspended particulates in canals are suscept...

Aquatic vegetation is a potential source of organic matter and nutrients for crop production and soil sustainability. However, its high water content and presence of toxic compounds have been major deterrents for commercial application. This split-pot study evaluated the application of Pistia stratiotes (PS) (water lettuce) and Lyngbya wollei (LW)...

AdditionAl index words. Musa acuminata, mill mud, cachaza, alternative substrate Nutrient leaching is a necessary, but wasteful part of growing nursery plants. Substrate, fertilization, and their interactions affect nutrient leaching. This study was designed to investigate nutrient leaching from tissue culture bananas during the acclimation phase i...

The rice water weevil, Lissorhoptrus oryzophilus Kuschel, is an important pest of rice (Oryza sativa L.) grown in Florida. Reports on the effect of flood depth on rice water weevil populations have been inconsistent. Our objective was to determine if flood depth has any significant effect on rice water weevil populations and other arthropods in ric...

Farm canals in the Everglades Agricultural Area (EAA) often contain an abundance of floating aquatic vegetation which assimilates P through thalli, shoots, and leaves and prevents the co-precipitation of P with calcium carbonate within the calcium-saturated canal water column. To test the effects of two prevalent aquatic weed species, water lettuce...

Pistia stratiotes and Lyngbya wollei are the two most common aquatic weeds that flourish in farm canals within the Everglades Agricultural Area of Florida. Identifying a useful application of these weeds would not only address important environmental concerns, but would also be an incentive for farmers to harvest it. The objective of this study was...

The activity of ammonia-oxidizing archaea (AOA) leads to the loss of nitrogen from soil, pollution of water sources and elevated emissions of greenhouse gas. To date, eight AOA genomes are available in the public databases, seven are from the group I.1a of the Thaumarchaeota and only one is from the group I.1b, isolated from hot springs. Many soils...

Purpose The Everglades Agricultural Area (EAA), USA, comprises nearly 280,000 ha of organic soil farmlands that are drained by a network of farm canals. During the wet summer season, the water-table in the farmlands is maintained by moving water from farm canals via low-fit, high-volume drainage pumps. The drainage pumping creates a hydraulic press...

The use of agricultural by-products as organic fertilizer could improve sugarcane (Saccharum spp) yields grown on sandy soils with low organic matter (OM) content. This study was designed to investigate three types of agricultural by-products in the Everglades Agricultural Area for their potential use as organic soil amendments and substitute inorg...

A portion of the northern Everglades in south Florida was drained at the beginning of the 20th century for agricultural and urban purposes, becoming what is known today as the Everglades Agricultural Area (EAA). Concerns about the quality of drainage water leaving the EAA basin prompted the Florida legislature to adopt the Everglades Regulatory pro...

Farm canals in the Everglades Agricultural Area (EAA) contain an abundance of floating and submerged aquatic vegetation (FAV, SAV). These species flourish in waters with high phosphorus (P) concentrations preventing the co-precipitation of P with the underlying limestone bedrock. Two most common variety of vegetation are water lettuce (Pistia strat...

Agricultural land management, such as fertilization, liming, and tillage affects soil properties, including pH, organic matter content, nitrification rates, and the microbial community. Three different study sites were used to identify microorganisms that correlate with agricultural land use and to determine which factors regulate the relative abun...

High phosphorus (P) in surface drainage water from agricultural and urban runoff is the main cause of eutrophication within aquatic systems in South Florida, including the Everglades. While primary sources of P in drainage canals in the Everglades Agricultural Area (EAA) are from land use application of agricultural chemicals and oxidation of the o...

Purpose Excess nutrients such as phosphorus (P) transported from the Everglades Agricultural Area (EAA) in South Florida, USA, to downstream water bodies have been identified as contributing to trophic imbalances within the Florida Everglades. Decades of farming drainage from the EAA has led to accumulation of sediments in regional canals which may...

Equilibrium phosphorus concentration (EPC) is the aqueous phosphorus (P) concentration at which no net adsorption or desorption occurs when a soil is in contact with water; and are typically determined experimentally by plotting the measured amount of sorption versus initial concentration of P. In this study we evaluated the effect experimental par...

For decades water from Lake Okeechobee is released into the Everglades Agricultural Area (EAA) for irrigation; and discharges from the EAA have been identified as contributors to the phosphors (P) enrichment of the Everglades. Despite the success of the Best Management Practice (BMP) program in the EAA, higher P concentrations and loads still exit...

The canals in the Everglades Agricultural Area contain an abundance of floating aquatic vegetation (FAV) and submerged aquatic vegetation (SAV). These FAV flourish in waters with high phosphorus (P) concentrations and prevent the co-precipitation of P with the limestone bedrock (CaCO3). To test the effects of FAV and SAV and the presence of sedimen...

The Everglades Agricultural Area (EAA) in South Florida, part of the historical Everglades, was initially drained in the early 20th century for agriculture and flood protection. The organic soils have been subject to subsidence caused by organic matter oxidation. Soils are deeper east of Lake Okeechobee compared to soils south of the lake. The area...

In Florida, state agencies are concerned about St. Augustinegrass [Stenotaphrum secundatum (Walt.) Kuntze] for being a possible high water user and excess (N) applications in home lawns. This has resulted in a desire by some municipalities to substitute St. Augustinegrass with bahiagrass (Paspalum notatum Flügge). Consequently, the aim of this stud...

Co-precipitation of phosphorus (P) with CaCO3 is well documented in aquatic systems with high Ca and alkalinity levels. We hypothesized that increased photosynthetic activities in farm canal waters free of floating aquatic vegetation (FAV) can enhance high water pH and co-precipitation of P with carbonate. In a glasshouse study, canal waters of P c...

The L40 canal is a perimeter canal surrounding the Arthur R. Marshall Loxahatchee National Wildlife Refuge (Refuge) that typically receives low P discharges at various flows from the stormwater treatment area, STA-1E. In the present study, the generalized linear mixed model, GLIMMIX, approach was used to evaluate total-P (TP) concentrations of L40...

Exotic plant species invasion can alter ecosystem nutrient dynamics and natural disturbance patterns. The Australian tree Melaleuca quinquenervia has extensively invaded the Florida Everglades and is currently being suppressed using mechanical, herbicidal, and biological control management strategies. While these methods have been evaluated based o...

The Everglades Agricultural Area (EAA), downstream of Lake Okeechobee in South Florida, was initially drained in the early 20th century for agriculture and flood protection. Drainage water from the EAA, enriched with P, has impacted the downstream Everglades ecosystem. The organic soils in the EAA have become shallower as a result of continuing oxi...

Water flow and P dynamics in a low-relief landscape manipulated by extensive canal and ditch drainage systems were modeled utilizing an ontology-based simulation model. In the model, soil water flux and processes between three soil inorganic P pools (labile, active, and stable) and organic P are represented as database objects. And user-defined rel...

a b s t r a c t Environmental impacts from drainage water phosphorus (P) loads from Everglades Agricultural Area (EAA) farms in South Florida led to the adoption of best management practices (BMPs). The BMPs have been very successful at reducing EAA farm drainage water P loads. However, analytical investigation into how environmental and management...

An ontology-based simulation (OntoSim) is a unique data modeling environment where soil-plant-nutrient processes are represented as database objects and the user-defined relationships among objects are used to generate computer code (Java) for running the simulation. The aim of this study was to model hydrologic processes of sugarcane-grown organic...

A mandatory best management practices (BMP) program was implemented in the Everglades Agricultural Area (EAA) farms basin-wide in 1995 as required by the Everglades Forever Act to reduce P loads in drainage water reaching the Everglades ecosystem. All farms in the EAA basin implement similar BMPs, and basin wide P load reductions have exceeded the...

The original project was designed to use a Lagrangian sampling design. The Lagrangian sampling, also termed plug sampling, is a method of stream sampling that tags a parcel of water using a tracer, and follows the tagged parcel using the tracer so that the same water parcel is sampled repeatedly through time (Mills et al., 1986). This method was te...

Phosphorus (P) enrichment has been observed in the historic oligotrophic Greater Everglades in Florida mainly due to P influx from upstream, agriculturally dominated, low relief drainage basins of the Everglades Agricultural Area (EAA). Our specific objectives were to: (1) investigate relationships between various environmental factors and P loads...

Goosegrass (Eleusine indica L.) is a serious weed in trafficked areas of bermudagrass (Cynodon spp.) golf and sports turf. The objective of this study was to evaluate soil compaction and canopy cover as determinants of goosegrass competition in bermudagrass turf in sand soil. Goosegrass cover, plant density, and soil penetration resistance (SPR) we...

Impact of stream sediments on surface water quality has been an area of active water-science research (Bostrom et al., 1988; Brunke and Gonser, 1997; Brunke et al., 1998; Dahm et al., 1998; Daroub et al., 2003; DiToro, 2001; Grimm and Fisher, 1984; Perkins and Underwood, 2001; Vollmer et al., 2002; Waldon and McCormick, 2003). Sediments play an imp...

Estimates of the number of species of bacteria per gram of soil vary between 2000 and 8.3 million (Gans et al., 2005; Schloss and Handelsman, 2006). The highest estimate suggests that the number may be so large as to be impractical to test by amplification and sequencing of the highly conserved 16S rRNA gene from soil DNA (Gans et al., 2005). Here...

SL-228-Sp, a 9-page illustrated fact sheet by O.A. Diaz, T.A. Lang, S.H. Daroub, and V.M. Nadal, is the Spanish language version of "SL228/SS448: Best Management Practices in the Everglades Agricultural Area: Controlling Particulate Phosphorus and Canal Sediments." It explains and discusses particulate P and sediment control practices, which serve...

SL-231-Sp, a 3-page illustrated fact sheet by O.A. Diaz, S.H. Daroub, R.W. Rice, T.A. Lang, V.M. Nadal, and M. Chen, is the Spanish language version of SL-231, "Best Management Practices in the Everglades Agricultural Area: Fertilizer Spill Prevention." It provides current implementation guidelines for this BMP designed to reduce drainage P loads i...

SL-232-Sp, a 5-page illustrated fact sheet by T.A. Lang, S.H. Daroub, O.A. Diaz, V.M. Nadal, and M. Chen, is the Spanish language version of SL-232, "Best Management Practices in the Everglades Agricultural Area: Fertilizer Application Control." It provides current implementation guidelines for this BMP designed to reduce drainage P loads in the Ev...

SL-225-Sp, a 6-page illustrated fact sheet by S.H. Daroub, O.A. Diaz, T.A. Lang, V.M. Nadal, and M. Chen, is the Spanish language version of SL-225, "Best Management Practices in the Everglades Agricultural Area: Soil Testing." It outlines the process of soil testing as an important tool for both fertilizer recommendations and as a BMP in this regi...

Silicon (Si) confers increased disease resistance and nutritional benefits for both sugarcane and rice. Sugarcane is the primary crop grown in the Everglades Agricultural Area (EAA) in south Florida, USA, and production inputs routinely include Si fertilization. Soil testing for Si is based on a 0.5 N acetic acid extraction procedure that was devel...

Rapid and accurate determination of low‐level (0.01 to 1.0 mg L) phosphorus (P) concentrations in farm canal water is important in evaluating water quality in the Everglades Agricultural Area (EAA) canals in south Florida. Two U.S. Environmental Protection Agency methods, persulfate digestion (365.1) and Kjeldahl digestion with mercury oxide (365.4...

Nutrient loading from the Everglades Agricultural Area and nearby urban communities plus water flow rate and canal size have signif- icantly influenced the amount of sediment and phosphorus (P) pools stored in the Water Conservation Area (WCA) canals in the Ever- glades.A study was conducted to characterize the potential impact that sediments might...

Flow adsorption calorimetry was used to investigate the energetics of arsenate sorption on amorphous aluminum hydroxide (AHO) and its effect on surface charge and ion exchange. Arsenate sorption at pH 5.7 was exothermic and the molar heats of adsorption were quite variable, ranging from -3.0 to -66 kJ/mol. Repetitive exposure of the same sample to...

A technique for determining the point of zero net charge (PZNC) using flow adsorption calorimetry was investigated. The rationale behind this method is that the heat of exchange, determined calorimetrically, is directly proportional to surface charge and that the PZNC can be equated to the pH at which the heats of cation exchange (CE) and anion exc...

Specific conductance in farm canals of the Everglades Agricultural Area (EAA) in south Florida is an important water quality parameter that was categorized as a parameter of concern according to an observed frequency of >5% excursions over the Class III water quality criterion and needed to be addressed as a part of the Everglades Regulatory Progra...

The South Florida Water Management District has developed a BMP table that lists the BMP practices that have been designed to reduce particulate P and sediment loads in drainage waters from Everglades Agricultural Area (EAA) farms. The purpose of this document is to explain and discuss these particulate P and sediment control practices. These pract...

Sugarcane (Saccharum spp.) is the primary crop on the Histosols of the Everglades Agricultural Area (EAA), where periodic floods and undesirably high water tables are increasing in occurrence and duration. Improved understanding of the physiologic responses of sugarcane to these conditions could help develop strategies to sustain high yields. The p...

Organic soils subside when they are drained continuously, primarily because of aerobic microbial activity. The purpose of this study was to determine the organic matter oxidation potential of an organic soil that is the result of intermittent flooding and draining in combination with different water table depths, some suitable for the culture of su...

Sugarcane (Saccharum spp.) in Florida is increasingly exposed to periodic floods and high water tables for extended durations. We evaluated the effects of periodic flooding, followed by drainage, on morphological characteristics and cane and sugar yields of two sugarcane genotypes. From 2000-2002, experiments were conducted in lysimeters filled wit...

Histosols of the Everglades Agricultural Area (EAA) are subsiding primarily from aerobic microbial oxidation. An experiment was conducted in a Histosol to evaluate methods [14C-benzoate oxidation (BO), soil respiration (CO2 evolution; RESP), and microbial biomass carbon (MBC)] of determining short-term organic matter (OM) oxidation potential under...

Nitrogen leaching from urban areas including turf and golf courses is a growing concern in south Florida. This study was conducted to determine whether adding a soil amendment, clinoptilolite zeolite (CZ), a mineral group of hydrated aluminosilicates, to typical sandy media of turf and golf courses could affect a change in the amount of N leaching....

Phosphorus (P) is a limiting nutrient affecting crop yields in many regions of the world, in particular in areas with highly weathered acid soils and calcareous alkaline soils. Given the many factors associated with P behavior in a range of soil environments, there is a need to go beyond site-specific situations. The use of crop simulation models i...

Suitable near infrared spectroscopy (NIRS) prediction equations offer the possibility of replacing conventional chemical analysis methods used in making P fertilizer recommendations in sugarcane (Saccharum spp. interspecific hybrids) leaves. Phosphorus concentrations in sugarcane leaves from three categories: parent (n = 125), fertilizer rate (n =...

Rapid screening for high leaf P concentration may help sugarcane (interspecific hybrids of Saccharum spp.) growers in the Everglades Agricultural Area reduce P in discharge water, an important component of Everglades restoration. The purpose of this study was to evaluate near-infrared reflectance spectroscopy (NIRS) as a potential tool to analyze s...

The distribution of lead in soil samples collected from both surface (0 to 10 cm) and profile (O 0 to 10 cm, E 11 to 30 cm, Eb 31 to 50 cm, Bw 51 to 100 cm, and C 181 to 200 cm) at a 14-year-old rifle/pistol shooting range located in central Florida were determined using EPA Method 3051a (microwave, HNO 3 /HCl=3:1, v/v). In addi-tion to total lead...

Phosphorus in the drainage waters from the Florida Everglades Agricultural Area (EAA) can have a substantial impact on the receiving waters of the Water Conservation Areas (WCA's) and the Everglades National Park. Growers in the EAA are required by law to adopt a set of Agricultural Best Management Practices (BMPs) appropriate to their specific ope...

The adoption of alternative management practices has been shown to increase soil organic matter. However, the effect of adopting these practices on soil phosphorus (P), especially organic P, is not clear. We evaluated the effect of such practices-mainly no-tillage, zero and low-chemical input, organic-based, row crop agricultural systems-on soil P...

Minimum tillage may alter soil P fractions through the application of P fertilizers and the deposition of organic matter on the surface rather than being incorporated into the soil. This study was conducted to determine whether no-tillage (NT) systems affected soil organic and inorganic P fractions and the transformation of P from residues applied...

A mandatory Best Management Practices (BMP) program was implemented on Everglades Agricultural Area (EAA) farms in 1995 as required by the Everglades Forever Act to reduce phosphorus (P) loads from drainage waters that enter the Everglades ecosystem. All farms in the EAA basin implement mandatory BMPs. Our objective was to determine long-term P loa...

SUMMARY

This document is SL 197, one of a series of the Soil and Water Science Department, Florida Cooperative Extension Service, Institute of Food and Agricultural Sciences, University of Florida. Published September 2002. This publication is also a part of the Florida Sugarcane Handbook, an electronic publication of the Agronomy Department. https://edis....