scholarly journals Environmental indicators in effluent assessment of rainbow trout (Oncorhynchus mykiss) reared in raceway system through phosphorus and nitrogen

2016 ◽  
Vol 76 (4) ◽  
pp. 1021-1028 ◽  
Author(s):  
M. A. B. Moraes ◽  
C. F. Carmo ◽  
Y. A. Tabata ◽  
A. M. Vaz-dos-Santos ◽  
C. T. J. Mercante
Keyword(s):  
Mass Balance ◽  
Management Practices ◽  
Low Frequency ◽  
Farming System ◽  
Environmental Indicators ◽  
Fish Biomass ◽  
Nutrient Loads ◽  
Feed Conversion ◽  
Feed Management ◽  
Low Efficiency

Abstract The phosphorus and nitrogen discharge via effluent of intensive trout farming system was quantified through the use of environmental indicators. The nutrient loads, the mass balance, the estimated amount of nutrients in feed and the amount of nutrients converted in fish biomass were calculated based on the concentrations of phosphorus (P) and nitrogen (N) in the feed and in the water. Of the offered feed, 24.75 kg were available as P and 99.00 kg as N, of these, 9.32 kg P (38%) and 29.12 kg N (25%) were converted into fish biomass and 15.43 kg P (62%) and 69.88 kg N (75%) were exported via effluent. The loads and the mass balance show the excessive discharge of nutrients via effluent, corroborated by the feed conversion ratio (2.12:1) due to the low efficiency of feed utilization, therefore, it is proposed the use of this zootechnical parameter as environmental indicator. In addition, feed management practices are not adequate, highlighting the low frequency of feeding during the day, excessive amount and low quality of feed offered. These results demonstrate the need for adequate feed management and the need for careful monitoring of effluent.

scholarly journals Nitrogen and phosphorus flux from the production of Nile tilapia through the application of environmental indicators

2017 ◽  
Vol 78 (1) ◽  
pp. 25-31 ◽  
Author(s):  
J. A. S. Osti ◽  
M. A. B. Moraes ◽  
C. F. Carmo ◽  
C. T. J. Mercante
Keyword(s):  
Best Management Practices ◽  
Nile Tilapia ◽  
Management Practices ◽  
Environmental Indicators ◽  
Conversion Ratio ◽  
Feed Conversion Ratio ◽  
Phase Iii ◽  
Production Cycle ◽  
Fish Biomass ◽  
Feed Conversion

Abstract We aimed in this study utilize environmental indicators as a quantitative method to evaluate and discuss the nitrogen (TN) and phosphorus (TP) flux by a production stage grow-out (termination) of Nile tilapia (Oreochromis niloticus) in fishpond. The TN and TP load, the mass balance, the input of TN and TP via feed and the converted nutrients in fish biomass are the environmental indicators applied in this study. During the production cycle (128 days), the system exported 15,931 g TN and 4,189 g TP that were related to the amount of feed supplied (r Pearson = 0.8825 and r = 0.8523, respectively), corroborated by the feed conversion ratio (1.61:1). The indicators showed that 26% TN and 45% TP were reversed into fish biomass, 62% TN and 40% TP were retained in the fishpond, and 12% TN and 15% TP were exported via effluent. The largest contribution of nutrients generated by the system and exported via effluent was observed in phase III and IV. This result is supported by the feed conversion ratio 2.14 and 2.21:1 obtained at this phase, a fact explained by the amount of feed offered and the fish metabolism. Application of environmental indicators showed to be an efficient tool to quantify flux of TN and TP produced during the grow-out period of Nile tilapia and therefore, guide management practices more sustainable. Concerning the environmental sustainability of the activity the implementation of best management practices such as the better control of the feed amount offered would lead to a smaller loss of TN and TP to the water. Furthermore, the use of better quality feeds would allow greater nutrient assimilation efficiency.

scholarly journals Bullfrog (Lithobates catesbeianus) farming system: water quality and environmental changes

2014 ◽  
Vol 26 (1) ◽  
pp. 9-17 ◽  
Author(s):  
Cacilda Thais Janson Mercante ◽  
André Martins Vaz-dos-Santos ◽  
Munique de Almeida Bispo Moraes ◽  
Jeniffer Sati Pereira ◽  
Júlio Vicente Lombardi
Keyword(s):  
Water Quality ◽  
Management Practices ◽  
Environmental Changes ◽  
Farming System ◽  
Human Consumption ◽  
Mixing Zone ◽  
Feed Conversion ◽  
Management Options ◽  
Monthly Basis ◽  
Lithobates Catesbeianus

INTRODUCTION: Frog farming, if not well managed, may cause environmental damages. The use of antibiotics, the organic discharge and the introduction of exotic species can disseminate risks such as eutrophication, changes in the water quality and organic pollution, factors that affect the human consumption. AIM: Evaluating the water quality of a bullfrog farming system, discussing their relations to production and the environment based on the current legislation. METHODS: Sampling was performed on a monthly basis from November 2006 to March 2007 during growth and fattening phases of bullfrog (Lithobates catesbeianus). Sample sites were distributed according to the water flow: upstream from the mixing zone, affluent (supply water), bay, effluent, mixing zone and downstream from the mixing zone. In the field, pH, electrical conductivity, dissolved oxygen, temperature and turbidity were measured. In laboratory, nitrogen, phosphorus and chlorophyll a concentrations were analyzed. RESULTS: The concentration of nutrients was determiner for water quality in the bay and its effluent. According to the current legislation, the effluent exceeded the limits for total phosphorus (> 0.030 mg L-1) and total nitrogen (> 1.27 mg L-1). Other variables presented acceptable values in light of the current laws. CONCLUSION: The high values of nutrients and other factors such as conductivity and turbidity are proportional to the animal growth due to the inadequate management practices evidenced by feed conversion rate. The following management options are proposed: maintaining the flow and decreased density of animals; maintaining the flow and density storage with adequate control of the food supply.

scholarly journals Daily mass balance of phosphorus and nitrogen in effluents of production sectors of trout farming system

2015 ◽  
Vol 27 (3) ◽  
pp. 330-340 ◽  
Author(s):  
Munique de Almeida Bispo Moraes ◽  
Clovis Ferreira do Carmo ◽  
Carlos Massatoshi Ishikawa ◽  
Yara Aiko Tabata ◽  
Cacilda Thais Janson Mercante
Keyword(s):  
Mass Balance ◽  
Development Stage ◽  
Environmental Indicators ◽  
Conversion Ratio ◽  
Feed Conversion Ratio ◽  
Environmental Indicator ◽  
Feed Conversion ◽  
Feeding Frequency ◽  
Feeding Management ◽  
Stage Of Development

Abstract Aim: The mass balance has recently been applied in Brazilian aquaculture. In relation to trout farming, few studies have used this methodology as environmental indicator, especially when considering each development stage of fish. The daily mass balance allows an estimate of nutrients discharge, because the sampling effort over 24 hours enables to monitor the variations throughout the day. This study aimed to identify the breeding sector (fingerlings, juveniles and adults) in trout farming contributes with the great discharge of phosphorus and nitrogen in the effluent. Methods The concentrations of total phosphorus (TP), orthophosphate (PO4-P), total nitrogen (TN) and ammonium (NH4-N) were determined in affluent and effluents of the production system. The environmental indicators were calculated based on the values of nutrients loads and by quantifying the daily discharge of nutrients from the mass balance method. Results Over the 24 hours, the trout farming exported an average of 0.26 kg TP, 0.11 kg PO4-P, 3.11 kg TN and 0.18 kg NH4-N. The discharge of phosphorus and nitrogen in the effluent was higher at night associated to feeding management (hours and feeding frequency) and the nocturnal habits of trout. The juvenile and adult sectors accounted for the greatest contribution of these nutrients, related the largest fish biomass and metabolism, supported by the feed conversion ratio of 1.95:1 and 2.01:1, respectively. Conclusion In order to reduce exports of phosphorus and nitrogen there is a need to adequate the feeding management (feeding frequency from two to four times per day according to the trout development stage; carry out feeding in times close at twilight due to the nocturnal habits of this specie; reduce excess of ration offered and use good quality ration considering the distinct nutritional requirements of each trout stage of development). Besides the mass balance, the feed conversion ratio is also an efficient tool to detect the efficiency of feed utilization; therefore, it is proposed its use as environmental indicator, aiming the aquaculture environmental sustainability.

Field Measurements and Simulation of Nitrogen Fate under Citrus Production

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 498c-498
Author(s):  
A. Fares ◽  
A.K. Alva ◽  
S. Paramasivam
Keyword(s):  
Mass Balance ◽  
Best Management Practices ◽  
Rainy Season ◽  
Crop Production ◽  
Management Practices ◽  
Root Zone ◽  
Field Measurements ◽  
Irrigation Scheduling ◽  
N Leaching ◽  
Citrus Production

Water and nitrogen (N) are important inputs for most crop production. The main objectives of nitrogen best management practices (NBMP) are to improve N and water management to maximize the uptake efficiency and minimize the leaching losses. This require a complete understanding of fate of N and water mass balance within and below the root zone of the crop in question. The fate of nitrogen applied for citrus production in sandy soils (>95% sand) was simulated using a mathematical model LEACHM (Leaching Estimation And Chemistry Model). Nitrogen removal in harvested fruits and storage in the tree accounted the major portion of the applied N. Nitrogen volatilization mainly as ammonia and N leaching below the root zone were the next two major components of the N mass balance. A proper irrigation scheduling based on continuous monitoring of the soil water content in the rooting was used as a part of the NBMP. More than 50% of the total annual leached water below the root zone was predicted to occur in the the rainy season. Since this would contribute to nitrate leaching, it is recomended to avoid N application during the rainy season.

Road Salt Application in Highland Creek Watershed, Toronto, Ontario - Chloride Mass Balance

2010 ◽  
Vol 45 (4) ◽  
pp. 451-461 ◽  
Author(s):  
Nandana Perera ◽  
Bahram Gharabaghi ◽  
Peter Noehammer ◽  
Bruce Kilgour
Keyword(s):  
Mass Balance ◽  
Management Practices ◽  
Chloride Concentration ◽  
Aquatic Organisms ◽  
Terrestrial Ecosystems ◽  
Road Salt ◽  
Winter Period ◽  
Chloride Mass Balance ◽  
Creek Watershed ◽  
Chloride Concentrations

Abstract Occurrence of increasing chloride concentrations in urban streams of cold climates, mainly due to road salt application, has raised concerns on its adverse effects on aquatic and terrestrial ecosystems. Therefore, there is a need for a better understanding of processes associated with road salt application and subsequent discharge into the environment in order to develop management practices to minimize detrimental effects of chlorides. The chloride mass analysis for the Highland Creek watershed based on four years of hourly monitoring data indicates that approximately 60% of the chlorides applied on the watershed enter streams prior to subsequent salting period, 85% of which occurs during the period between November and March. Contribution of private de-icing operations on chloride mass input within Highland Creek watershed was estimated to be approximately 38%, indicating its significance in overall chloride mass balance. Salt application rates, as well as chloride output in the streams, vary spatially based on land use, influencing chloride concentrations in surface waters. The estimated groundwater chloride concentration of 275 mg/L indicates that some aquatic organisms in Highland Creek would potentially be at risk even outside the winter period under dry weather flow conditions.

scholarly journals Environmental Drivers and Age Trends in Site Productivity for Oak in Southern Poland

Forests ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 209
Author(s):  
Luiza Tymińska-Czabańska ◽  
Jarosław Socha ◽  
Marek Maj ◽  
Dominika Cywicka ◽  
Xo Viet Hoang Duong
Keyword(s):  
Nitrogen Deposition ◽  
Management Practices ◽  
Additive Model ◽  
Climatic Conditions ◽  
Environmental Indicators ◽  
Environmental Drivers ◽  
Site Productivity ◽  
Site Factors ◽  
Wide Range ◽  
Si Model

Site productivity provides critical information for forest management practices and is a fundamental measure in forestry. It is determined using site index (SI) models, which are developed using two primary groups of methods, namely, phytocentric (plant-based) or geocentric (earth-based). Geocentric methods allow for direct site growth modelling, in which the SI is predicted using multiple environmental indicators. However, changes in non-static site factors—particularly nitrogen deposition and rising CO2 concentration—lead to an increase in site productivity, which may be visible as an age trend in the SI. In this study, we developed a geocentric SI model for oak. For the development of the SI model, we used data from 150 sample plots, representing a wide range of local topographic and site conditions. A generalized additive model was used to model site productivity. We found that the oak SI depended predominantly on physicochemical soil properties—mainly nitrogen, carbon, sand, and clay content. Additionally, the oak SI value was found to be slightly shaped by the topography, especially by altitude above sea level, and topographic position. We also detected a significant relationship between the SI and the age of oak stands, indicating the long-term increasing site productivity for oak, most likely caused by nitrogen deposition and changes in climatic conditions. The developed geocentric site productivity model for oak explained 77.2% of the SI variation.

scholarly journals Meteorological conditions over Antarctic blue-ice areas and their influence on the local surface mass balance

2001 ◽  
Vol 47 (156) ◽  
pp. 37-50 ◽  
Author(s):  
Richard Bintanja ◽  
Carleen H. Reijmer
Keyword(s):  
Mass Balance ◽  
Low Frequency ◽  
Meteorological Conditions ◽  
Surface Mass Balance ◽  
Surface Mass ◽  
Wind Speeds ◽  
Dry Conditions ◽  
The Difference ◽  
Sublimation Rates ◽  
Different Characteristics

AbstractThis paper addresses the causes of the prevailing meteorological conditions observed over an Antarctic blue-ice area and their effect on the surface mass balance. Over blue-ice areas, net accumulation is zero and ablation occurs mainly through sublimation. Sublimation rates are much higher than over adjacent snowfields. The meteorological conditions favourable for high sublimation rates (warm, dry and gusty) are due to the specific orographic setting of this blue-ice area, with usually a steep upwind mountainous slope causing strong adiabatic heating. Diabatic warming due to radiation, and entrainment of warm air from aloft into the boundary layer augment the warming. The prevailing warm, dry conditions explain roughly 50% of the difference in sublimation, and the different characteristics of blue ice (mainly its lower albedo) the other 50%. Most of the annual sublimation (∼70%) takes place during the short summer (mainly in daytime), with winter ablation being restricted to occasional warm, dry föhn-like events. The additional moisture is effectively removed by entrainment and horizontal advection, which are maximum over the blue-ice area. Low-frequency turbulent motions induced by the upwind mountains enhance the vertical turbulent transports. Strong gusts and high peak wind speeds over blue-ice areas cause high potential snowdrift transports, which can easily remove the total precipitation, thereby maintaining zero accumulation.

Nutrients budget and effluents characteristics in polyculture of scampi (Macrobrachium rosenbergii) and Indian major carps ponds using organic inputs

2012 ◽  
Vol 66 (7) ◽  
pp. 1540-1548 ◽  
Author(s):  
Subhendu Adhikari ◽  
Bharat Chandra Sahu ◽  
Lambodar Dey
Keyword(s):  
Macrobrachium Rosenbergii ◽  
Nutrient Budget ◽  
Catla Catla ◽  
Average Weight ◽  
Cow Dung ◽  
Nutrient Loads ◽  
Feed Conversion ◽  
Indian Major Carps ◽  
Main Input ◽  
Major Carps

Experiments were conducted for the study of nutrient budget in farmers' ponds (0.4–0.6 ha) in Orissa, India, at stocking densities of 0.30–0.38/m2 for scampi (Macrobrachium rosenbergii) and 0.60–0.70/m2 for Indian major carps (Catla catla, Labeo rohita and Cirrhinus mrigala). The average initial body weights of scampi and the major carps were 0.02 and 8–10 g, respectively. The culture period was 272–292 days. Feed was the main input. The FCR (feed conversion ratio) varied from 1.78 to 1.83. Feed and cow dung were applied to these ponds as organic inputs. At harvest time, the average weight of scampi and carps varied from 73 to 92 g and from 718 to 820 g, respectively. Among all the inputs, feed alone accounted for 97.60% total nitrogen (N), 97.90% total phosphorus (P) and 94.72% total organic carbon (OC), respectively. The harvest of scampi and carps accounted for recovery of 52.45% N, 19.43% P and 18.12% OC, respectively. N, P and OC accumulated in sediment were 38.31, 71.40 and 69.50%, respectively. The median nutrient loads in the fish pond effluents were equivalent to 0.58 kg of inorganic N, 0.135 kg of P and 8.83 kg of total OC per ton of Indian major carps and scampi production.

Can farm-management practices reduce the impact of house mouse populations on crops in an irrigated farming system?

2004 ◽  
Vol 31 (6) ◽  
pp. 597 ◽  
Author(s):  
Peter R. Brown ◽  
Micah J. Davies ◽  
Grant R. Singleton ◽  
J. David Croft
Keyword(s):  
House Mouse ◽  
Management Practices ◽  
Farming System ◽  
Farm Management ◽  
Advisory Panel ◽  
Farming Practices ◽  
Management Actions ◽  
Winter Cereals ◽  
Significant Difference ◽  
The Impact

The impacts of a range of farm-management practices on house mouse (Mus domesticus) populations were tested in a large replicated field study in a complex irrigated farming system in southern New South Wales, Australia. An advisory panel, made up of farmers, extension officers, industry representatives and scientists developed a series of best-practice farm-management actions to minimise the impact of mice. Twelve experimental sites were split into six treated sites, where farmers were encouraged to conduct the recommended practices, and six untreated sites, where farmers conducted their normal farming practices. Mouse abundance was generally low to moderate for the 4-year project (5–60% adjusted trap success). We found significant reductions in population abundance of mice on treated sites when densities were moderate, but no differences when densities were low. Biomass of weeds and grasses around the perimeter of crops were significantly lower on treated sites because of applications of herbicide sprays and grazing by sheep. We could not detect any significant difference in mouse damage to crops between treated and untreated sites; however, levels of damage were low (<5%). Yields of winter cereals and rice crops were significantly higher on treated sites by up to 40%. An analysis of benefits and costs of conducting farming practices on treated sites compared with untreated sites showed a 2 : 1 benefit to cost ratio for winter cereals, 9 : 1 for rice and 4 : 1 for soybeans.

Current issues and controversies in assessing the environmental impacts of livestock production.

2021 ◽  
Vol 16 (044) ◽  
Author(s):  
Judith L. Capper
Keyword(s):  
Environmental Impacts ◽  
Resource Use ◽  
Management Practices ◽  
Ghg Emissions ◽  
Livestock Production ◽  
Environmental Indicators ◽  
Environment Impact ◽  
Trade Offs ◽  
Specific Practice ◽  
Over Time

Abstract The environment impact of livestock production is one of the most significant issues within agriculture. Global concerns over climate change, resource use, pollution and other environment indicators means that producers must implement practices and systems to reduce environmental impacts, yet this may only be achieved through assessments that allow impacts to be quantified, benchmarked and improved over time. Although environmental indicators are widely accepted, the metrics by which these are assessed continue to evolve over time as assessment objectives gain clarity and focus, and as the science relating to controversial topics (e.g. global warming or carbon sequestration) becomes more refined. however, significant negative trade-offs may occur between different metrics and denominators such that a specific practice or system may appear to have greater or lesser impacts, depending on assessment methodology. A number of tools and models have been developed to empower producers in quantifying environmental impacts, which will be increasingly important is satisfying future consumers' hunger for information as well as food. These tools must be supplied in tandem with information as to the potential consequences of changing management practices and systems. At present however, tools available are based on differing methodologies, are often opaque in their background calculations and do not necessarily account for all the factors that influence environmental impacts from livestock. There is a clear need for robust tools that can be used as standards for assessing environmental impacts from the global livestock industry and that go beyond GHG emissions to produce a more rounded holistic assessment.

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