Agricultural production and pollutant runoffs in QuŽbecÕs Chaudi re river watershed: what are the potential environmental gains?
0
Citation
0
Reference
20
Related Paper
Abstract:
Despite imposition of strict environmental standards in Quebec, the impact of agricultural activities on water quality remains a concern, particularly in the Chaudi re-Appalaches region.This regionOs intensive animal and plant productions lead to excess phosphorus, nitrogen and sediments.This paper analyzes the environmental efficiency of agricultural producers in the Chaudi re river watershed, located south of Quebec City. We adopt a stochastic approach applied to parametric distance functions to data collected from 210 farms. Results show that, on average, crop producers are more efficient than livestock producers. In terms of emissions of phosphorus and nitrogen, the environmental efficiencies of producers are similar, at 0.804 and 0.820 respectively.For sediment runoff, however, the environmental efficiencies are lower on average, at 0736. Overall, the agricultural producers from this watershed could have achieved productivity gains in excess of 20%, while simultaneously reducing their emissions of pollutants.Cite
An ecological-economic model is presented for linking the production function approach to existing food web models, such as ECOPATH, in order to identify optimal management strategies for watersheds. The model is applied to the Tonameca watershed, located on the coast of Oaxaca in Mexico. The model is an ecological diagnosis linked to agriculture, fisheries and ecotourism and production functions and profits. Social optimization and externalities are also analysed. The ecological results show that the Tonameca river and lagoon are not extremely polluted and only one scenario of nitrogen run-off estimation indicates high levels of nutrient loading. The mangrove food web analysis results show that the ecosystem is healthy and can support large amounts of nitrogen in water. The agriculture production function and profits depend mainly on water extraction and fertilizer use. Fisheries production function and profits depend on fish biomass and nitrogen concentration in water, which in turn is a measure of fertilizer used in agriculture. Ecotourism production and profits are a function of labour and crocodile biomass related to fish biomass and nitrogen concentration in water. The increase of fertilizer use influences positively in a short term the economic activities but not in a long term. The optimum levels of each activity are evaluated as well as the optimum point of nitrogen run-off for avoiding a negative externality from agriculture to fisheries and ecotourism. Finally, management recommendations for the Tonameca watershed are proposed based on the Mexican framework for coastal and watershed management.
Cite
Citations (2)
Current day large animal facilities generate more manure than they need on their own feed production areas. Excessive nutrient applications deteriorate groundwater (nitrogen) and surface water quality (nitrogen and/or phosphorus). Due to differences in environmental and economic characteristics, adjacent regions may have differing objectives for nitrogen and phosphorus abatement. We postulate an analytical model of upstream agricultural and downstream recreational regions, and analyze optimal policies that consider both regions. We show that depending on the environmental and economic characteristics, tightening upstream regulation with respect to loading of one nutrient only might increase the downstream loading of the other. As the prevailing regulatory tool for livestock production is the Nutrient Management Plan based on nitrogen standard; and because livestock production is the main source of man-made nutrient loads to environment, the model is of high importance. Our model contributes to literature by i) differentiating (the impacts of) manure regulation between the livestock farm and the adjacent crop production farm ii) showing how this differentiation is carried over to relative and absolute amounts of nitrogen and phosphorus loading due to changes in nutrient application and uptake; and due to changes in application areas iii) allowing for regional differences in abatement objectives.
Nutrient pollution
Cite
Citations (1)
Impact of crop rotations on optimal selection of conservation practices for water quality protection
This research integrates modern multiobjective optimization tools, water quality modeling capability, and data on costs of implementing conservation practices to develop a tradeoff frontier of cost-efficient nonpoint source pollution reduction solutions, which can be used to derive the watershed-level pollution abatement cost curve. Farmers9 decisions, both on the intensive and the extensive margin, are likely to affect the shape of the tradeoff frontier as well as the mix of conservation practices selected for achievement of given nutrient reduction goals. In this paper, we wish to explore the consequences of changes in the cropping practices on the intensive margin and changes in the amount of cropland on the extensive margin on the baseline water quality as well as the shape of the tradeoff frontier and the mix of conservation practices. An empirical application focuses on a typical Midwestern agricultural watershed, Squaw Creek watershed in central Iowa. Using detailed crop production budgets, we follow Secchi and Babcock (2007) to demonstrate an alternative land-use scenario, which could arise from recently observed changes in crop prices and production costs. We find that the change in cropping practices effects direct changes in the shape of the tradeoff frontier and the mix and location of conservation practices selected to achieve particular nutrient loading reductions. In particular, we find that a potential shift to more corn (Zea mays L.)-intensive crop rotations and an increase in the amount of cropland in the watershed may lead to increased loadings of both nitrate and phosphorus and that additional conservation investments are required to maintain water quality gains achieved under the baseline (historic) cropping practices. In terms of conservation practices selected, the optimal placement of terraces appears robust to the changes in crop rotations and amount of cropland in the alternative land-use scenario.
Production–possibility frontier
Row crop
Nutrient pollution
Margin (machine learning)
Baseline (sea)
Cite
Citations (19)
Cite
Citations (14)
One of the main concerns of the environmental scientists and policy makers is related to the environmental compatibility of current agricultural systems and, in particular, to the losses of chemical fertilizers and manure in surface and ground-waters, as a consequence of run-off and leaching phenomena. In most cases European recent agrienvironmental schemes envisaged specific measures for the reduction of fertilizer rates and the control of manure applications, in order to limit the releases of nutrients in surface and ground-waters. Substantial financial resources are invested in those measures and therefore the issue raises interest in monitoring and evaluating their effectiveness. Nutrient balance indicators are often used for quantitative assessment of the effectiveness of the measures in limiting the environmental impact of farming activities. N-surplus is one of the most commonly used indicators. The paper refers the results of a research project aimed at assessing the outcomes of agri-environmental measures implemented in the Venice Lagoon Watershed with an approach based upon the gross nitrogen balance, called "Nboxes". The results of applying the Nboxes procedure to a sample of 550 farms set are presented, evidencing the expectations of greater effectiveness in terms of nitrogen surplus reduction from the measure C.5.1.3a and C.5.1.3b (low input farming and buffer strips). Measures supporting improved irrigation systems, controlled drainage and more rational livestock nutritional programmes and technologies, showed instead only limited potential for tangible contributions to the reduction of nitrogen surplus in cultivated soils.
Buffer strip
Nutrient pollution
Cite
Citations (7)
Nutrient pollution
Cite
Citations (55)
Reducing poverty in rural areas of developing countries requires sustained and sustainable increases in agricultural water productivity. However, aside from traditional measures of precipitation, little is known about water available to farmers or how productively they use it. We present a crop‐water productivity index (a ratio of the value of annual crop production to a dimensionless potential water availability index) for large water basins using readily available low‐resolution data. The index is transferable, permits direct inter‐basin comparisons, and is simple to calculate. We calculate the index for each municipality in the São Francisco river basin in Brazil. No clear patterns linking water availability and value of agricultural output are evident, even though clusters of municípios with high‐ and low‐crop‐water productivity emerge, and the former may be useful in guiding policies aimed at increasing water productivity. Finally, analyses of the effects of information uncertainty on the crop‐water productivity index suggest that the returns to agricultural investments in certain places in the São Francisco river basin are more risky than others. Improvements in data quality and quantity can help refine estimates of the index and reduce their uncertainty.
Water use
Cite
Citations (6)
Nutrient pollution
Environmental Pollution
Cite
Citations (86)
Conventional drainage systems tend to aggravate runoff and nutrient leaching problems on farms especially during the off-season. This study uses a biophysical economic model to identify, evaluate and determine multifunctional benefits of implementing and establishing nitrogen rate fertilizer application and conservation tillage practices as best management practices (BMPs) in the lower Mississippi River Basin (MRB). Simulation results showed that agricultural producers generally preferred no tillage to conventional tillage in reducing nutrient runoffs from fields because of higher net revenue per acre. Finally, given nitrogen runoff restrictions, farmers reduced crop acreage and nitrogen fertilizer application rates to help minimize losses.
Nutrient Management
Cite
Citations (3)
SWAT model
Watershed Management
Water Framework Directive
Cite
Citations (63)