Aspects of phosphorus pollution from aquaculture

Phosphorus is an essential element for living organisms and exists in waterbodies as dissolved and particulate forms. Phosphorus is required for optimum growth, feed efficiency, bone development and maintenance of acid-base regulation in fish. The presence of high concentration of phosphates in water may indicate presence of pollution as it may accelerate plant growth and disrupt the aquatic ecosystem thereby benefiting certain species and altering species diversity in affected areas. Eutrophication of waterbodies is often correlated with the phosphorus loading into the environment and aquaculture has been identified as one of the sources of phosphorus pollution. Details of the impacts of eutrophication is given in Bernhardt (1981). Phosphorus must be provided in fish feed because of its low concentration in water. Studies made in Europe and Northern America have revealed a phosphorus surplus in most commercial feeds which is above actual requirements; or is supplied in a form which is unavailable to the fish. Surplus phosphorus is excreted, while unavailable phosphorus is passed out in the feces. Discharge of phosphorus from fish farms and hatchery effluents have caused phosphorus pollution in Nordic countries, North America and Europe. This article examines the path of phosphorus pollution, quantification/prediction of phosphorus load from aquaculture and remedial measures.

The effect of water quality on coarse fish productivity and movement in the Lower River Irwell and Upper Manchester Ship Canal a watercourse recovering from historical pollution

This is the Effect of water quality on coarse fish productivity and movement in the Lower River Irwell and Upper Manchester Ship Canal: a watercourse recovering from historical pollution report produced by the Environment Agency in 2003. The aim of this study was to investigate the impact of water quality upon coarse fish population dynamics in a lowland, urban watercourse. All of the research carried was undertaken in the lower River Irwell and upper Manchester Ship Canal, between February 1998 and December 2001. Of particular interest was the natural sustainability of the urban fishery given recent concern raised in the angling community over an apparent decline in coarse fish populations in lowland rivers. The research described in this report has concentrated upon the role of water quality in determining coarse fish population dynamics, and in particular: The impact of water quality upon fish growth and productivity; The impact of poor water quality and low dissolved oxygen concentrations upon fish distribution and movement; The impact of water quality upon the sexual development of fish.

Investigation of rising nitrate concentrations in groundwater in the Eden Valley, Cumbria: Phase 1 project scoping study

This is the Investigation of rising nitrate concentrations in groundwater in the Eden Valley, Cumbria report produced by the Environment Agency in 2003. This report focuses on groundwater nitrate concentrations in the Eden Valley. Most boreholes in the Eden Valley had nitrate concentrations less than 20 mg/l but a significant number had higher concentrations, some exceeding the EC maximum admissible concentration for drinking water of 50 mg/l. The main objectives of this report were to investigate the causes of rising nitrate concentrations in groundwater in the Permo-Triassic sandstone aquifers of the Eden Valley area and provide sufficient understanding of the groundwater and surface water flow system, including the sources of the nitrate contamination and the processes controlling nitrate movement, so that possible management options for reversing this trend can be considered.

River Lune Pollution at Lancaster in July 1949

Houses close to River Lune at Lancaster, North West England, UK. This photo shows the polluted River Lune in July 1949. This photo is part of a Photo Album that includes pictures from 1935 to 1954.

Implications of using On-Farm Flood Flow Capture to recharge groundwater and mitigate flood risks along the Kings River, CA

Two large hydrologic issues face the Kings Basin, severe and chronic overdraft of about 0.16M ac-ft annually, and flood risks along the Kings River and the downstream San Joaquin River. Since 1983, these floods have caused over $1B in damage in today’s dollars. Capturing flood flows of sufficient volume could help address these two pressing issues which are relevant to many regions of the Central Valley and will only be exacerbated with climate change. However, the Kings River has high variability associated with flow magnitudes which suggests that standard engineering approaches and acquisition of sufficient acreage through purchase and easements to capture and recharge flood waters would not be cost effective. An alternative approach investigated in this study, termed On-Farm Flood Flow Capture, involved leveraging large areas of private farmland to capture flood flows for both direct and in lieu recharge. This study investigated the technical and logistical feasibility of best management practices (BMPs) associated with On-Farm Flood Flow Capture. The investigation was conducted near Helm, CA, about 20 miles west of Fresno, CA. The experimental design identified a coordinated plan to determine infiltration rates for different soil series and different crops; develop a water budget for water applied throughout the program and estimate direct and in lieu recharge; provide a preliminary assessment of potential water quality impacts; assess logistical issues associated with implementation; and provide an economic summary of the program. At check locations, we measured average infiltration rates of 4.2 in/d for all fields and noted that infiltration rates decreased asymptotically over time to about 2 – 2.5 in/d. Rates did not differ significantly between the different crops and soils tested, but were found to be about an order of magnitude higher in one field. At a 2.5 in/d infiltration rate, 100 acres are required to infiltrate 10 CFS of captured flood flows. Water quality of applied flood flows from the Kings River had concentrations of COC (constituents of concern; i.e. nitrate, electrical conductivity or EC, phosphate, ammonium, total dissolved solids or TDS) one order of magnitude or more lower than for pumped groundwater at Terranova Ranch and similarly for a broader survey of regional groundwater. Applied flood flows flushed the root zone and upper vadose zone of nitrate and salts, leading to much lower EC and nitrate concentrations to a depth of 8 feet when compared to fields in which more limited flood flows were applied or for which drip irrigation with groundwater was the sole water source. In demonstrating this technology on the farm, approximately 3,100 ac-ft was diverted, primarily from April through mid-July, with about 70% towards in lieu and 30% towards direct recharge. Substantial flood flow volumes were applied to alfalfa, wine grapes and pistachio fields. A subset of those fields, primarily wine grapes and pistachios, were used primarily to demonstrate direct recharge. For those fields about 50 – 75% of water applied was calculated going to direct recharge. Data from the check studies suggests more flood flows could have been applied and infiltrated, effectively driving up the amount of water towards direct recharge. Costs to capture flood flows for in lieu and direct recharge for this project were low compared to recharge costs for other nearby systems and in comparison to irrigating with groundwater. Moreover, the potentially high flood capture capacity of this project suggests significant flood avoidance costs savings to downstream communities along the Kings and San Joaquin Rivers. Our analyses for Terranova Ranch suggest that allocating 25% or more flood flow water towards in lieu recharge and the rest toward direct recharge will result in an economically sustainable recharge approach paid through savings from reduced groundwater pumping. Two important issues need further consideration. First, these practices are likely to leach legacy salts and nitrates from the unsaturated zone into groundwater. We develop a conceptual model of EC movement through the unsaturated zone and estimated through mass balance calculations that approximately 10 kilograms per square meter of salts will be flushed into the groundwater through displacing 12 cubic meters per square meter of unsaturated zone pore water. This flux would increase groundwater salinity but an equivalent amount of water added subsequently is predicted as needed to return to current groundwater salinity levels. All subsequent flood flow capture and recharge is expected to further decrease groundwater salinity levels. Second, the project identified important farm-scale logistical issues including irrigator training; developing cropping plans to integrate farming and recharge activities; upgrading conveyance; and quantifying results. Regional logistical issues also exist related to conveyance, integration with agricultural management, economics, required acreage and Operation and Maintenance (O&M).

On-Farm Flood Flow Capture – addressing flood risks and groundwater overdraft in the Kings Basin, with potential applications throughout the Central Valley

Project fact sheet prepared in cooperation with the USDA Natural Resources Conservation Service and the Kings River Conservation District.

International legal instruments relevant to fisheries and fishing communities : a handbook. Theme IV. Environmental pollution

This handbook provides detailed information for a wide range of legal instruments relevant to fisheries and fishworkers. It covers 114 legal instruments, categorized into the following seven themes: Theme I. Human Rights, Food Security, Women and Development. Theme II. Environment and Sustainable Development. Theme III. Oceans and Fisheries Management. Theme IV. Environmental Pollution Theme V. Fishing Vessels and Safety at Sea Theme VI. Labour Theme VII. Trade The handbook also includes the working of the instruments (decision-making bodies, monitoring and implementation agencies, periodicity of meetings, rules for participation in meetings of the decision-making bodies and implementation agencies for States and non-governmental organizations), regional instrument and agencies. Apart from being a ready reckoner to the instruments, it highlights the important sections of relevance to fisheries or small-scale fisheries and fishworkers. The companion CD-ROM provides the full texts of the instruments in a searchable database. The handbook will be useful for fishworker and non-governmental organizations, and also for researchers and others interested in fisheries issues.

Mine-waste pollution of Bear Butte Creek, Black Hills, South Dakota

Effluents leaving the Gilt Edge Mining properties in the Black Hills near Deadwood, South Dakota, were collected during April 1940. Field studies of these effluents and of the streams receiving them were made at the time and subsequently laboratory assays and analyses have been completed. ... Data from this particular case of mine waste pollution are presented here.

Algae and water pollution in Mahi Estuary

Distribution of phytoplankton, chlorophyll A and phaeophytin was studied at different locations in the Mahi Estuary, Gujarat, India during 1982. The water quality at the discharge point was poor while the region away from it was relatively unpolluted. The results indicated a wide range of variation in phytoplankton population (7.68-5010, 96 x 10 super(4) cells/l, chl. a 2.22-58.22 mg/m super(3) and phaeophytin [0.20-10.21 mg/m super(3)]. The ratio of chl. a/phaeophytin were remarkably low at highly polluted stations. Higher abundance of the genera Oscillatoria and Nitzschia were recorded at polluted stations. The diversity of species at the unpolluted station was higher (1.56) as compared to the polluted station (1.07).

Marine pollution and zooplankton: some recent trends in marine pollution studies

The presence of even very minute quantities of pollutants may become harmful either due to their direct effect on zooplankton or indirectly due to the transfer of the pollutants to other trophic levels through zooplankton. The recent trend in marine pollution studies is therefore to find out the effects of very minute quantities of these pollutants on marine zooplankton and the methods of their accumulation and transfer to the organisms of higher trophic level including man. A review of laboratory and field studies concerning the effects of pollutants such as hydrocarbons, crude oil, heavy metals, pesticides and heated waste water on the survival, breeding, movement, faecal pellet production, growth and development on marine zooplankton is presented.