Water Quality and Agriculture
Harmful algal blooms (HABs) represent both challenges and opportunities for agricultural water management. Our research investigates the complex relationship between cyanobacterial blooms and agricultural irrigation practices, examining both the risks posed by cyanotoxin contamination and the potential benefits of utilizing HAB-enriched water sources in semi-arid regions where water scarcity drives the need for alternative irrigation sources (Newton & Melaram, 2023).
While HAB-contaminated water containing toxins can significantly affect plant development and inhibit essential physiological processes, emerging research suggests that under controlled conditions, certain components of cyanobacterial blooms may provide agricultural benefits. The utilization of alternative water sources, including reclaimed wastewater and HAB-contaminated water, is being considered as one potential viable solution for the agricultural sector in water-scarce regions (Newton & Melaram, 2023).
Cyanobacteria-enriched compost represents an innovative approach to sustainable agriculture, transforming potentially harmful algal biomass into beneficial soil amendments. Our ongoing research investigates how controlled composting processes can harness the bioactive compounds present in cyanobacterial biomass to enhance soil health and promote plant growth while mitigating the risks associated with cyanotoxin exposure.
The composting process appears to break down harmful cyanotoxins while preserving beneficial compounds that can improve soil microbial communities and nutrient cycling. Previous studies have shown that while direct application of HAB material poses risks, proper composting may offer a pathway to beneficial utilization of this abundant biomass. Cyanobacterial fertilizer, which contains living cyanobacteria cultures that aid in harnessing solar energy, nutrients, and water resources essential to plant growth, has become popular in recent years.
Figure 1. Bioactive compound pathways and mechanisms of cyanobacterial benefits in sustainable agriculture applications (Melaram et al., in progress).
Figure 2. Study design and mechanism overview showing physiological pathways of bioactive compounds in cyanobacteria-enriched agricultural applications (Melaram et al., in progress).
Microcystins represent the most concerning cyanotoxins for agricultural applications, with their persistence in irrigation water posing significant risks to crop safety and human health (Melaram et al., 2022). Our comprehensive research examines contamination pathways, bioaccumulation patterns, and health implications associated with microcystin presence in agricultural systems.
Microcystin Bioaccumulation Levels in Agricultural Crops
| Crop Type | Microcystin Uptake Level | Concentration Range | Health Risk Assessment |
|---|---|---|---|
| Leafy greens (lettuce, cabbage) | High | 12.3-22.8 μg/kg | Elevated concern |
| Root vegetables (carrot) | Moderate | 10.5-12.6 μg/kg | Moderate concern |
| Alfalfa and wheat (roots) | High | 1.3 mg/kg | Elevated concern |
Microcystin bioaccumulation levels in different crop types when irrigated with contaminated water. WHO tolerable daily intake: 0.04 μg/kg body weight. Data compiled from multiple studies reviewed in Melaram et al. (2022).
Freshwater Cyanobacterial Harmful Algal Blooms, Human Health, and Sustainable Agriculture
Relationship between recreational microcystin exposure and asthma hospitalizations in Florida - evidence from an algal bloom dashboard
In ProgressInvestigating health impacts of recreational cyanotoxin exposure using Florida's algal bloom monitoring dashboard to quantify associations between HAB events and respiratory health outcomes in exposed populations.
Distribution and occurrence of cyanotoxins in Lake Corpus Christi - a pilot investigation
In ProgressPilot investigation of spatial and temporal cyanotoxin patterns in a major Texas water supply system, establishing baseline monitoring data for regional water management and public health protection.
Bioactive applications of cyanobacteria-enriched compost in sustainable agriculture - a short review
In ProgressComprehensive review examining beneficial applications of processed cyanobacterial biomass in sustainable agriculture, identifying safe utilization pathways for HAB biomass while promoting soil health and crop productivity.
Plant impacts and health risks of harmful algal blooms in agricultural irrigation - a scoping review
In ProgressScoping review of agricultural impacts and human health risks from irrigated HAB water, providing comprehensive risk assessment for agricultural cyanotoxin exposure pathways and management strategies.