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1.
Bioresour Technol ; 272: 582-593, 2019 Jan.
Article in English | MEDLINE | ID: mdl-30352731

ABSTRACT

Intensive livestock farming cannot be uncoupled from the massive production of manure, requiring adequate management to avoid environmental damage. The high carbon, nitrogen and phosphorus content of pig manure enables targeted resource recovery. Here, fifteen integrated scenarios for recovery of water, nutrients and energy are compared in terms of technical feasibility and economic viability. The recovery of refined nutrients with a higher market value and quality, i.e., (NH4)2SO4 for N and struvite for P, coincided with higher net costs, compared to basic composting. The inclusion of anaerobic digestion promoted nutrient recovery efficiency, and enabled energy recovery through electricity production. Co-digestion of the manure with carbon-rich waste streams increased electricity production, but did not result in lower process costs. Overall, key drivers for the selection of the optimal manure treatment scenario will include the market demand for more refined (vs. separated or concentrated) products, and the need for renewable electricity production.


Subject(s)
Manure , Anaerobiosis , Animals , Composting , Swine
2.
Food Nutr Bull ; 36(2): 196-210, 2015 Jun.
Article in English | MEDLINE | ID: mdl-26121702

ABSTRACT

BACKGROUND: Burundi is one of the world's poorest countries, coming last in the Global Food Index (2013). Yet, a large majority of its population depends on agriculture. Most smallholder families do not produce enough to support their own families. OBJECTIVE: To estimate the optimal crop mix and resources needed to provide the family with food containing sufficient energy, fat, and protein. METHODS: This study uses mathematical programming to obtain the optimal crop mix that could maximize output given the constraints on production factor endowments and the need to feed the household. The model is calibrated with household-level data collected in 2010 in Ngozi Province in northern Burundi. Four models are developed, each representing a different farm type. The typology is based on 2007 data. Model predictions are compared with data collected during a revisit of the area in 2012. RESULTS: By producing a smaller number of crops and concentrating on those in which they have a comparative advantage, and trading produce and input with other farms, large and medium-sized farms can improve their productivity and hire extra workers to supplement family labor. Predictions of crops to be planted coincided to a high degree with those that farmers planted 2 years after our survey on newly acquired plots. CONCLUSIONS: Despite land scarcity, it is still possible for households that own land to find optimal crop combinations that can meet their minimal food security requirements while generating a certain level of income. Nearly landless households would benefit from the increased off-farm employment opportunities. With only 0.05 ha of land per capita, the annotation Nearly Landless is used to highlight the limited access to land observed in this farm category.


Subject(s)
Agriculture/methods , Crops, Agricultural/growth & development , Food Quality , Food Supply/methods , Burundi , Dietary Fats/analysis , Dietary Proteins/analysis , Energy Intake , Family Characteristics , Food , Humans , Models, Theoretical , Poverty , Reproducibility of Results
3.
Plant Biotechnol J ; 12(2): 135-46, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24460889

ABSTRACT

The introduction of semi-dwarfing, high-yielding and nutrients-responsive crop varieties in the 1960s and 1970s alleviated the suffering of low crop yield, food shortages and epidemics of famine in India and other parts of the Asian continent. Two semi-dwarfing genes, Rht in wheat and Sd-1 in rice heralded the green revolution for which Dr. Norman Borlaug was awarded the Nobel Peace Prize in 1970. In contrast, the revolutionary new genetics of crop improvement shamble over formidable obstacles of regulatory delays, political interferences and public misconceptions. India benefited immensely from the green revolution and is now grappling to deal with the nuances of GM crops. The development of GM mustard discontinued prematurely in 2001 and insect-resistant Bt cotton varieties were successfully approved for commercial cultivation in 2002 in an evolving nature of regulatory system. However, the moratorium on Bt brinjal by MOEF in 2010 meant a considerable detour from an objective, science-based, rigorous institutional process of regulatory approval to a more subjective, nonscience-driven, political decision-making process. This study examines what ails the regulatory system of GM crops in India and the steps that led to the regulatory logjam. Responding to the growing challenges and impediments of existing biosafety regulation, it suggests options that are critical for GM crops to take roots for a multiplier harvest.


Subject(s)
Biotechnology/legislation & jurisprudence , Crops, Agricultural/genetics , Genetic Engineering/legislation & jurisprudence , Plants, Genetically Modified/genetics , Agriculture , Biotechnology/standards , DNA, Bacterial/genetics , Food, Genetically Modified/standards , India , Insecticides , Oryza/genetics , Solanum melongena/genetics , Triticum/genetics
4.
Sci Total Environ ; 421-422: 94-101, 2012 Apr 01.
Article in English | MEDLINE | ID: mdl-22353175

ABSTRACT

Within the framework of the nitrate directive, member states have the opportunity to apply for derogation, i.e. increasing fertilisation standards under certain conditions. Several EU regions have utilised this opportunity, but each in a different way, resulting in six very different derogation policies within the EU in 2009. This paper focuses on the differences between the policies applied and makes an assessment with regard to the impact of these differences on the application rate for derogation, the manure surplus and the cost of allocating manure. Based on the MP-MAS model described by Van der Straeten et al. (2010) the different scenarios are applied on a single case area (Flanders) and the economic effects have been simulated. Results show considerable differences between the policy alternatives, leading to the conclusion that member states not only have to focus on whether or not to allow derogation, but also on the actual details of the derogation policy. Granting derogation at parcel level (plot of land), instead of farm level, increases the potential effect of derogation; the level of increase in fertilisation standards under derogation determines the application rate for derogation: a higher increase leads to a higher application rate.


Subject(s)
Agriculture , Environmental Monitoring , Environmental Pollution/legislation & jurisprudence , Nitrates/analysis , Agriculture/economics , Agriculture/legislation & jurisprudence , Agriculture/standards , Costs and Cost Analysis , Environmental Monitoring/economics , Environmental Monitoring/legislation & jurisprudence , Environmental Monitoring/standards , Environmental Pollution/prevention & control , European Union , Fertilizers , Government Regulation , Manure , Models, Economic , Public Policy
5.
J Environ Manage ; 92(9): 2109-18, 2011 Sep.
Article in English | MEDLINE | ID: mdl-21524839

ABSTRACT

This paper estimates farmers' individual irrigation water demand functions employing the information hidden in individual farmers' technical efficiency. This information is extracted through the development of a new deductive methodology based on inverse Data Envelopment Analysis (DEA) models. The empirical results for Tunisia show that farmers who are more technically efficient have less elastic irrigation water demand functions; these farmers would adjust demand only to a limited extent and they can afford the water price. In contrast, water pricing significantly affects those that are less efficient. These farmers shift towards a different cropping pattern using significantly less water and more land when the price of water increases. Thus, higher water prices would threaten this category's livelihood if their efficiency is not improved. However, if the technical efficiency of these farmers were to improve, then it would be more difficult to reach water saving objectives since their demand will also become highly inelastic. The findings have important implications in view of the objectives of Tunisia water policy which include:full cost recovery, continuity of the irrigation activity, and water saving at the national level.


Subject(s)
Agricultural Irrigation/economics , Water Supply/economics , Environmental Policy/economics , Statistics as Topic/methods , Tunisia
6.
J Dairy Res ; 76(2): 234-40, 2009 May.
Article in English | MEDLINE | ID: mdl-19281628

ABSTRACT

This paper uses a Markov chain model to analyse the dynamics in farm-size distribution among the Flemish dairy sector and the impact of quota policy regulation on such changes. The model predicts a decline of 24% in number of farms in 2014 compared with the current situation with a more liberal exchange policy and a decline of 18% with a restricted quota exchange policy. From these Markov chain model results, we analysed the impact of farm-size distribution on eight different milk quality parameters (total bacterial count, somatic cell count, coliform count, freezing point, urea-N, fat content and protein content and penalty-points). In general, larger farms produce higher quality milk than smaller farms, especially with respect to the microbiological parameters (total bacterial count, somatic cell count and coliform count). The change in farm-size distribution from a liberal quota exchange policy would decrease the average total bacterial count by 18.0%, the somatic cell count by 2.1% and the coliform count by 11.0%. The aggregate performance of the other parameters are smaller with improvements in all cases of <1%.


Subject(s)
Dairying/legislation & jurisprudence , Milk/standards , Models, Economic , Animals , Belgium , Cattle , Markov Chains , Milk/chemistry , Milk/microbiology
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