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Showing papers on "Organic farming published in 1995"


Journal ArticleDOI
TL;DR: Organic farming has become a well-defined and certified alternative to conventional farming in North America and Europe and is generally considered important, but it is not clear which practices will improve sustainability and maintain adequate productivity.
Abstract: There are several major concerns about current practices in high-input conventional agriculture. The most important concern in many agricultural areas is loss of topsoil (38). On average, about 20 metric tons of topsoil are lost per hectare per year in the United States (15,38). This can amount to more than half of the topsoil layer in 100 years of continuous corn production (15). Soil erosion also results in reductions in organic matter, water penetration and availability, and rooting depth (38,39). Another important concern for some areas in the United States and many areas in Europe ts the effect of nitrate and pesticides on the environment, specifically in ground and surface water. In addition, pesticide efficacy has often been diminished, for example as a result of insensitivity of the targeted organisms to organic pesticides or enhanced biodegradation of these pesticides. Finally, the general public is very concerned about human health and safety and pesticide residues on food, whether this is justified or not. All these concerns have raised questions about the sustainability of conventional agriculture (8,32,36). Although the development of alternative agricultural systems is generally considered important, it is not clear which practices will improve sustainability and maintain adequate productivity. Many alternative agricultural systems exist, but only organic farming (also called biological farming or ecofarming) has become a well-defined and certified alternative to conventional farming in North America and Europe. Organic farming is characterized by the absence of synthetic fertilizers and pesticides and the use of organic amendments such as animal manures, green manures, and composts to maintain soil fertility (32). Usually crop rotations are longer and spatial diversity is greater under organic management than under conventional management. In addition, reduced tillage or no-till is practiced on

170 citations


Journal ArticleDOI
TL;DR: The results suggest that soil-management practices can significantly affect the susceptibility of crops to pests, and do so without adversely affecting plant productivity.

136 citations



Journal ArticleDOI
TL;DR: The main difference is that biodynamic farmers add eight specific amendments, called preparations, to their soils, crops, and composts as mentioned in this paper, which can improve biological soil properties and increase crop root growth.
Abstract: Biodynamic and organic farming are similar in that both are ecologically oriented and do not use chemical fertilizers and pesticides. The main difference is that biodynamic farmers add eight specific amendments, called preparations, to their soils, crops, and composts. Recently, there has been an increasing interest in biodynamic farming practices and systems because they show potential for mitigating some detrimental effects of chemical-dependent conventional agriculture. Only a few studies examining biodynamic methods or comparing biodynamic farming with other farming systems have been published in the refereed scientific literature, especially in English. This paper summarizes data from previous studies, both published and unpublished (theses), that have compared biodynamic and conventional farming systems with respect to soil quality or profitability. These studies have shown that the biodynamic farming systems generally have better soil quality, lower crop yields, and equal or higher net returns per hectare than their conventional counterparts. Two studies that included organic management treatments with and without the preparations showed that the preparations improved biological soil properties and increased crop root growth. However, more research is needed to determine whether the preparations affect soil physical, chemical, and biological properties and crop growth and, if so, their mode of action.

114 citations


Journal ArticleDOI
TL;DR: In this article, a system approach was used to study N turnover and N efficiency on 16 conventional and 14 organic private Danish farms with mixed animal (dairy) and crop production.
Abstract: Separate focus on crop fertilization or feeding practices inadequately describes nitrogen (N) loss from mixed dairy farms because of (1) interaction between animal and crop production and between the production system and the manager, and (2) uncertainties of herd N production and crop N utilization. Therefore a systems approach was used to study N turnover and N efficiency on 16 conventional and 14 organic private Danish farms with mixed animal (dairy) and crop production. There were significant differences in N surplus at the farm level (242 kg. N/ha. vs. 124 kg. N/ha. on conventional and organic dairy farms respectively) with a correlation between stocking rate and N surplus. N efficiency was calculated as the output of N in animal products divided by the net N import in fodder, manure and fertilizer. N turnover in herd and individual crops calculated on selected farms showed differences in organic and conventional crop N utilization. This is explained via a discussion of the rationality behind the current way of planning the “optimum fertilizer application” in conventional agriculture. The concept of marginal N efficiency is insufficient for correcting problems of N loss from dairy farms. Substantial reductions in N loss from conventional mixed dairy farms is probably unlikely without lower production intensity. The concept of mean farm unit N efficiency might be a way to describe the relation between production and N loss to facilitate regulation. This concept is linked to differing goals of agricultural development—i.e. intensification and separation vs. extensification and integration. It is discussed how studies in private farms—using organic farms as selected critical cases—can demonstrate possibilities for balancing production and environmental concern.

107 citations


Journal ArticleDOI
TL;DR: In this article, the authors compared the agronomic, economic, and ecological performance of alternative (organic), conventional, and reduced-till farming systems over a 7-year period.
Abstract: We compared the agronomic, economic, and ecological performance of alternative (organic), conventional, and reduced-till farming systems over a 7-year period. We evaluated the sustainability of the various systems regarding several concerns, including soil erosion, pollution potential, whole-farm productivity, energy use, environmental stress, economic performance, and farm size. The alternative systems relied primarily on forage legumes (alfalfa or clover) as substitutes for the pesticides and commercial fertilizers used in the other systems.Two studies were established in northeastern South Dakota in 1985. Study I emphasized row crops, Study II small grains. The alternative system in Study I, which included alfalfa hay in the rotation, was the most productive, both agronomically and economically. In Study II, the alternative system included a green manure crop (clover) in the 4-year rotation and had the lowest agronomic production; however, its economic performance was similar to the conventional system's. Year-to-year variability in production was lowest in the alternative systems. The alternative systems in both studies were the most energy-efficient, and the reduced-till systems the least. Judged by the distribution of nitrate-N in the soil profile, the potential for groundwater pollution was higher in the conventional and reduced-till systems in Study I than in the alternative system.The alternative systems in both studies depended less on government payments for their profitability. Results in Study I also showed that more widespread adoption of alternative systems would tend to halt or slow the trend of ever-increasing farm size. These studies suggest that alternative systems are more sustainable in this agro-climatic area.

103 citations


Book ChapterDOI
TL;DR: In this paper, the effect of organic management on soil microbial ecology was investigated using soils collected from the Rodale Institute Research Center's long-term Farming Systems Trial (FST) experiment, which included a manured and a cover cropped organic rotation and a conventionally managed grain based rotation.
Abstract: In order to achieve sustainability in managed ecosystems we must understand management impacts on soil processes and clarify the regulatory role of the microbial community on these processes. Crop rotation and organic management practices are thought to have positive impacts on the microbial biomass; however, the specific impacts of crop rotation organic management on soil microbial ecology are largely unknown. The effect of organic management on soil microbial ecology was investigated using soils collected from the Rodale Institute Research Center’s long-term Farming Systems Trial (FST) experiment. The FST, begun in 1981, included a manured and a cover cropped organic rotation and a conventionally managed grain based rotation. Soil respiration rates and 13C-isotope fate in a companion study suggest that the biomass characteristics of the FST treatment soils were different in November 1991. However, direct measurement of the microbial community at this time using Phospholipid Fatty Acid Analysis (PLFA) did not identify statistically significant treatment based differences in soil biomass characteristics. Variability among the PLFA profiles of treatment replicates was as great as variability between farming systems. Treatment based trends were observed among selected PLFAs, particularly those present in large amounts, that were consistent with indirect biomass and biomass-dependent measures. Overall, PLFA profiles, soil respiration rates and 13C-cycling suggested that the organic cover cropped soil had the Largest and most heterogeneous microbial population while the biomass of the organic-manure amended soil was the least heterogeneous, and the most metabolically active.

86 citations


Journal ArticleDOI
TL;DR: It is too early in the trial to state categorically that any one system is more sustainable than another, although trends are now emerging.
Abstract: In 1989, funding was provided to establish a large-scale (16-ha), long-term trial at Roseworthy campus. The trial aims to compare organic, biodynamic, integrated, and conventional broadacre farming systems for attributes of sustainability. It is overseen by a 13-member management committee comprising farmers with experience in each practice, agronomists, and soil scientists. Through the monitoring of indicators such as soil physical, chemical, and biological changes, product quality, economics, crop water usage, and energy requirements, the comparative advantages or disadvantages of each system are being evaluated in terms of productivity, profitability, and environmental sustainability. After 6 years, significant differences between systems are apparent in economic returns and soil available phosphorus (P) levels. The biodynamic treatment has the highest gross margins, followed by conventional, organic, and integrated. Conversely, available P levels on the biodynamic and organic treatments have declined 12 and 9%, respectively, since the start of the trial, while both the integrated and conventional treatments have increased soil P levels. In summary, it is too early in the trial to state categorically that any one system is more sustainable than another, although trends are now emerging. Weed management remains the main impediment to high production levels on the organic and biodynamic treatments, while input costs, variable yields, and low returns for grazed pastures are major constraints to high economic returns on the integrated and conventional systems.

85 citations


Journal ArticleDOI
Ulrich Köpke1
TL;DR: In this paper, Nitrogen management in organic agriculture is discussed focussing on strategies maximizing nitrogen input (source: N2-fixation) and minimizing nitrate losses onsite (field losses) and off-site (losses from manure heaps).
Abstract: Nitrogen management in organic agriculture is discussed focussing on strategies maximizing nitrogen input (source: N2-fixation) and minimizing nitrate losses on-site (field losses) and off-site (losses from manure heaps). Due to a strong relationship between grain yield/amount of N in grains and N2-fixation in pulse-crops or total dry matter yield and N2-fixation in fodder legumes, e.g. grass/clover mixtures, nitrogen fixation can be maximized by selecting the best site-adapted (best yielding) species, varieties or mixtures, respectively. Strategies to reduce nitrate losses are based on N-sinks, that is, plants taking up soil-borne and residual nitrogen during or after growth of legumes efficiently, e.g. brassica-underseeds in faba beans, catch crops, or following crops with great sink capacity for nitrogen. In order to keep pre-winter mineralization as low as possible (minimizing N-source) turn over of grass/clover can be postponed or tillage intensity can be reduced in depth or frequency. Gaseo...

53 citations


Journal Article
TL;DR: The authors examined differences between organic and conventional fruit and vegetable growers in Massachusetts, emphasizing characteristics that might be especially significant given that agriculture is only a small portion of the economy of this urbanized state.
Abstract: This study examined differences between organic and conventional fruit and vegetable growers in Massachusetts, emphasizing characteristics that might be especially significant given that agriculture is only a small portion of the economy of this urbanized state. Thirteen certified organic and 13 conventional fruit and vegetable growers in Massachusetts were interviewed during farm visits and by telephone. The organic farms on average are much smaller than the conventional farms and provide a much smaller fraction of their operators9 family income. The organic growers entered farming more recently than their conventional counterparts, often bringing idled land back into production to get started. They are strongly committed to organic methods, derive many intangible rewards from farming, and generally do not rate their problems as very serious.

26 citations



Book
06 Sep 1995
TL;DR: The first edition of the first edition by the late Anne Scott was published in 1989 as mentioned in this paper.It was used as a reference for the second edition of Anne Scott's book " Useful Organic Farming Web Site Web Site Addresses".
Abstract: Foreword to the First Edition by the late Anne Scott Acknowledgements Useful Organic Farming Web Site Addresses 1 Introduction 2 Grassland Productivity Grassland in Britain Reasons for predicting the productivity of organic grassland Factors influencing herbage yield Methods of predicting grassland production The effect of white clover Herbage utilisation Silage and hay production References: 3 Dairy, Beef, and Sheep Production Milk production Beef production Sheep production References 4 Pig and Poultry Production Pig production Poultry production References 5 Arable Production Systems Rotations Varieties Weeds Crop area Nutrient removal and supply Farmyard manure and composting Crop yields Arable crops References 6 Farm Size and and Enterprise Combinations Farm size Enterprise combinations Animal systems Enterprises and finance References 7 Organic Standards: Problems and Solutions Beef calves Beef Pigs Poultry Dairy cows Sheep Weed control Disease and pest control References Financial Management of the Farm Cash flow Costings References Further Reading 9 Marketing Organic Produce Challenges and opportunities Current market channels and products Organic symbol Price Market research and assessing your market Final decision Outlets References Further reading 10 Progress by Organic Farmers Insufficient organic grassland during conversion The value and methods of introducing white clover The control of internal parasites by grazing management The phosphate story Veterinary problems on organic farms Selling organic meat Selling organic milk Yeo Valley Organic Company Organic Cheese Chisel Farm, Dorset Good Herdsmen The Watermill, Little Salkeld, Penrith References 11 Organic Farming-- The Future Index

Journal ArticleDOI
TL;DR: Based on grower crop loss data from 1985–1987 and field and storage assessments from 1987, important pests and diseases of organic vegetables in Denmark are identified.
Abstract: Based on grower crop loss data from 1985–1987 and field and storage assessments from 1987, important pests and diseases of organic vegetables in Denmark are identified. The most important pests are cabbage root fly (Delia radicum), onion neck rot (Botrytis allii) and carrot rust fly (Psila rosae). The organic growers employ cultural plant protection methods such as placement and timing of crops, crop rotation, crop selection and field sanitation extensively, while direct control methods are rarely applied. Growers' perceptions of pest problems and crop loss due to pest and disease damage in organically grown vegetables change with marketing patterns and quality demands.


Journal ArticleDOI
TL;DR: The fundamental processes that influence nitrate leaching are similar in all farming systems and research into the processes operating in conventional agriculture also contributes to an understanding of N cycles in organic farming.
Abstract: The fundamental processes that influence nitrate leaching are similar in all farming systems and research into the processes operating in conventional agriculture also contributes to an understanding of N cycles in organic farming. Many of the strategies that have been proposed for reducing N leaching in conventional agriculture are also applicable to organic farming. The relevance of much research to organic agriculture is limited by differences in the organic matter content and biological activity of organically and conventionally managed soils with the result that quantitative information about organic systems cannot always be derived from conventional agriculture. There is a particular need for information about N fluxes in whole-farm systems, particularly those involving grass/arable rotations.

01 Aug 1995
TL;DR: In this paper, the nitrogen balance of individual 'conventional' and 'organic' systems will depend greatly on the circumstances and management practices of individual farms and therefore it is not possible to generalise that one system is always better than the other in terms of nitrate leaching risk.
Abstract: Key Conclusions 1. The crop rotations of organic systems maintain landscape diversity and biodiversity whilst the maintenance of field boundaries on organic units produces benefits to a wide range of organisms. 2. Inorganic nitrogen fertilisation and herbicide treatments of conventionally managed grassland has reduced the floral diversity of permanent pastures and maintained the low diversity of re-seeded pastures, greatly reducing their value as wildlife habitats. 3. Pesticide use is responsible for the removal of food sourcesfor birds and mammals in the form of weeds and invertebrates, as well as removing whole populations of potentially beneficial insects. 4. The majority of water pollution incidents from farms are caused during storage and spreading of cattle and pig slurries. A higher proportion of organic cattle and virtually all organic pigs are kept on solid manure systems and therefore are les of a risk. 5. The nitrogen balance of individual 'conventional' and 'organic' systems will depend greatly on the circumstances and management practices of the individual farms. Consequently it is not possible to generalise that one system is always better than the other in terms of nitrate leaching risk. With this qualification the literature does indicate that generally, organic systems offer less risk of nitrate leaching. 6. Organic systems are less likely to cause loss of phosphate into surface and ground waters. Both leaching and loss in eroded soil are likely to be reduced. 7. Organic management practicess such as rotations, the regular use of manures and non-use of pesticides usually increase soil organic matter contents. 8. Organic practices are likely to increase earthworm numbers compared to conventional systems. The increased numbers are universally acknowledged to benefit soil fertility although such effects are difficult to quantify. 9. Soil erosion is less of a problem on organic units. 10. Accumulations of copper and zinc in soils are much reduced in organic systems because organic pig and poultry producers do not supplement feeds with these metals as growth promoters. Copper fungicides are more widely used on organic farms and their use should be carefully monitored to prevent harmful effects. 11. The practices adopted by organic farmers can reduce emissions of nitrous oxide and methane. Ammonia emissions will not necessarily be less in organic than in conventional farming. 12. Organic farmers adopt practices which benefit the landscape. They maintain and introduce features largely because they are required by the Organic Standards to do so. They introduce such management practices because they are technically necessary for successful organic production.

Journal ArticleDOI
TL;DR: In this paper, the amount of applied farmyard manure within a crop rotation has been investigated, where higher dosages are focussed on a few crops as a traditional procedure or regular amendments of low dosages according to the recommendations of the Swiss Organic Biological Method.
Abstract: Nutrient provision for plants in organic farming systems is mainly based on the use of on-farm sources, i.e. farmyard manure, handled by different techniques, urine and slurry; off-farm sources, i.e. different composts and mineral or organic fertilizers; and the integration of leguminous and non-leguminous plants in the crop rotation. Depending on the chemical composition processed farmyard manure tends to enhance the fertilizing aim of manuring strategies if partly rotted material, rich in quickly mineralizable N and C compounds, is added to soils, whereas soil fertility is the main goal if composts with a low biodegradability are applied. Concerning the amount of applied farmyard manure within a crop rotation there are various alternatives; i.e. higher dosages are focussed on a few crops as a traditional procedure or regular amendments of low dosages according to the recommendations of the Swiss Organic Biological Method. Continuous amendments of elevated quantities of composts if fortified wit...

Journal Article
TL;DR: The status of organic farming in the Netherlands was introduced concisely, the conceptions of organic farms, organic farm and organic agricultural products were given, and the development in organic farming was discussed in this article.
Abstract: The status of organic farming in the Netherlands was introduced concisely,the conceptions of organic farming,organic farm and organic agricultural products in the Netherlands were given, and the development of organic farming in the Netherlands was discussed in this paper.


Journal ArticleDOI
TL;DR: In this article, the authors present an alternative approach to food production with inherent characteristics which can limit the potential disruption which is the inevitable consequence of ‘conventional’ farming.
Abstract: Nitrate contamination of ground and surface waters by leaching has increased over the past four decades. The productive capacity of intensive farming has become a problem and the environmental and social consequences are unacceptable. ‘Alternative’ approaches to food production are increasingly important. Organic farming systems represent the most well defined alternative with inherent characteristics which can limit the potential disruption which is the inevitable consequence of ‘conventional’ farming. Nitrate leaching is the result of intensification of agriculture involving regionalisation and specialisation of farming systems reliant on fertilisers, other agrochemical inputs and animal feedstuffs. Rotational cropping within mixed farming systems dependant on a low external input of nitrogen has largely been replaced. National and international diets dictate food production priorities which have been met by sophisticated food—and agri-businesses. Nitrate leaching is one cumulative consequence ...







Journal ArticleDOI
TL;DR: A voluntary pilot Nitrate Sensitive Area (NSA) scheme to assess the impact of changed husbandry practices on nitrate leaching has been in operation in England for three years as discussed by the authors.
Abstract: European Community legislation will require controls upon agriculture to reduce nitrate leaching. A voluntary pilot Nitrate Sensitive Area (NSA) Scheme to assess the impact of changed husbandry practices on nitrate leaching has been in operation in England for three years. It is proposed to expand it in 1994 under the EC Agri-Environment Regulation. Research findings have shown that livestock manures applied in autumn and early winter increase nitrate leaching from both arable and grassland. Cover crops reduce the loss of nitrate. The initial loss from straw- based manures is less than from slurries and poultry manure. The original proposals for the future NS As included limits on the use of all manures which could have prevented organic farms from participating in such schemes. These plans have been modified in a way which will allow many organic systems to join the Scheme but not outdoor pig or poultry units. Organic farmers hope that when Vulnerable Zones are delineated under the EC Nitrates D...



Dissertation
01 Jan 1995
TL;DR: In this paper, the effects of organic crop rotation system on soil chemical fertility were investigated in two organic plots lying adjacent to conventional plots of identical soil type (Manawatu silt loam) in Autwnn and Spring.
Abstract: Studies of soil nutrient fertility status of the organic and conventional plots at the Flock House cropping and organic units, Bulls, were undertaken to investigate the effects of organic crop rotation system on soil chemical fertility. Soil samples (0-75 nun, 75-150 mm, 150-300 mm depths) were collected from two organic plots lying adjacent to conventional plots of identical soil type (Manawatu silt loam) in Autwnn and Spring. The crop rotation plots were established in 1988. Soil samples were analysed for total C, total N, mineralizable N, extractable P (Olsen), exchangeable K, CEC and pH. Earthworm surface casts collected from the surface of these plots were also analysed for exchangeable K and CEC. Results of this study showed that after seven years of conversion to organic management, there were significant quantitative increases in the soil nutrient levels at topsoil depth 0-7 5 mm. Organic plot number 3 (OP3), now under clover based pasture showed higher percent of organic C and N than the organic plot under continuous cultivation (OP5) and conventional plot (CP8). Mineralizable N was significantly higher in the soil of OP3 and the mean topsoil (0-75 mm) value increased from 104 to 139 J.Lg g· (67%) from Autumn to Spring collected soils. Crop rotation under continuous cultivation resulted in decrease of mineralizable N from 90 to 30 J.Lg g· (150%) from Spring to Autumn collected soils at depth 075 mm. Extractable soil P (Olsen) remained significantly high in CP8 in both Autumn and Spring seasons.