Showing papers on "Organic farming published in 2004"

Impact of long-term conventional and organic farming on the diversity of arbuscular mycorrhizal fungi

Abstract: Previous work has shown considerably en- hanced soil fertility in agroecosystems managed by organic farming as compared to conventional farming. Arbuscular mycorrhizal fungi (AMF) play a crucial role in nutrient acquisition and soil fertility. The objective of this study was to investigate the diversity of AMF in the context of a long-term study in which replicated field plots, at a single site in Central Europe, had been cultivated for 22 years according to two "organic" and two "conventional" farming systems. In the 23rd year, the field plots, carrying an 18-month-old grass-clover stand, were examined in two ways with respect to AMF diversity. Firstly, AMF spores were isolated and morphologically identified from soil samples. The study revealed that the AMF spore abundance and species diversity was sig- nificantly higher in the organic than in the conventional systems. Furthermore, the AMF community differed in the conventional and organic systems: Glomus species were similarly abundant in all systems but spores of Acaulos- pora and Scutellospora species were more abundant in the organic systems. Secondly, the soils were used to establish AMF-trap cultures using a consortium of Plantago lanceolata, Trifolium pratense and Lolium perenne as host plants. The AMF spore community developing in the trap cultures differed: after 12 months, two species of the Acaulosporaceae (A. paulinae and A. longula) were consistently found to account for a large part of the spore community in the trap cultures from the organic systems but were found rarely in the ones from the conventional systems. The findings show that some AMF species present in natural ecosystems are maintained under organic farming but severely depressed under conven- tional farming, indicating a potentially severe loss of ecosystem function under conventional farming.

Producers and consumers of organic meat: A focus on attitudes and motivations

Abstract: Research into organic production is internationally widespread but has rarely focused on producer's motivations for adopting organic farming techniques and whether organic consumers share their values. As conventional agricultural prices remain depressed, questions arise surrounding producer's motivations towards organic production. For example, are motivations based on economic rather than ethical decisions? Additionally, what motivations underpin consumer's organic purchases and are those values shared between producers and consumers? Using postal questionnaires, the attitudes and motivations of both producers and consumers towards organic livestock production, are explored. Future recommendations are made to the industry with regard to the UK market for organically produced meat.

Risk and risk management in organic agriculture: Views of organic farmers

Abstract: In a series of focus groups during 2001 and 2002, organic farmers from different regions of the United States identified a wide range of risks to their operations. The focus groups were facilitated by the University of Maryland in cooperation with a research team from USDA's Economic Research Service, to explore the risks faced by organic farmers, how they are managed, and needs for risk management assistance. Contamination of organic production from genetically modified organisms was seen as a major risk, particularly by grain, soybean and cotton farmers. Focus-group participants producing grains and cotton—many of whom knew about and had obtained crop insurance—raised concerns about coverage offered, including the need for insurance to reflect the higher prices received for organic crops. Most fruit and vegetable producers participating in the focus groups had little knowledge of crop insurance. When provided with basic information about crop insurance, operators of small fruit and vegetable farms were skeptical about its usefulness for their type of operation.

Organic Farming: Policies and Prospects

Abstract: Organic farming - a grassroots movement taken over by policy? organic farming in Europe at the dawn of the new millennium - farms, land area and regional distribution, markets, institutions, research and innovation, European policies for organic farming in the 1990s, the development of organic farming in selected countries, conclusion organic farming's contribution to policy objectives - environmental performance, food quality, farm income, rural development, surplus reduction and government expenditure, criticism of organic farming policy a changing policy environment - agenda 2000, EU enlargement, WTO negotiations, possible futures, organic farming and agricultural policy recommendations for future organic farming policy - an integrated approach, status quo analysis, objectives and strategic decisions, instruments and addressees, monitoring and control, conclusions references - addresses of organic farming organizations, international organizations, research organizations, producer associations.

Use of sown wildflower strips to enhance natural enemies of agricultural pests

Abstract: Intensive agriculture and excessive use of agrochemicals have resulted in an impoverished wildlife in agricultural landscapes, especially in arable landscapes but also in perennial high input crops. The elimination of semi-natural habitats, simplification of crop rotations as well as high input of fertilisers and pesticides is considered to be responsible for the severe decline of biological diversity that has been observed (e.g. Aebischer 1991). These practices can reduce habitat quality and remove the necessary habitat structure that is important to many natural enemies. Moreover, agricultural landscapes are increasingly being simplified; with natural and semi natural areas fragmented and replaced altogether by large monocultural fields. As a consequence, most of the natural enemies depending on such semi-natural habitats for overwintering (Sotherton 1985; Lys and Nentwig 1994; Pfiffner and Luka 2000) need to disperse further to reach summer feeding habitats like agricultural crops. Fragmentation and loss of suitable habitats has caused natural enemies to decline in species diversity and abundance, and has even resulted in extinctions (Fahrig 1997) and loss of biological control functions (Kruess and Tscharntke 1994). Such landscape-scale aspects in biological control are explored in more detail in chapter 4. Nowadays, a desirable goal in agricultural landscapes is the enhancement of biotic diversity through the use of sustainable farming methods and the conservation and reestablishment of non-crop habitats. Agri-environmental programs have been established in several European countries (e.g. rural development and set-aside programs). Since 1993, the Swiss government has subsidised low-input and sustainable-farming methods (e.g. low-input integrated crop management, organic farming) and the establishment of non-crop habitats. Farmers are encouraged to increase the amount of these non-crop habitats including low-input habitats in order to reverse the observed decline of farmland fauna and to conserve or improve the functions and services of the agroecosystems. It has been demonstrated that habitat manipulation of the environment can enhance the survival of natural enemies and thereby improve their efficiency as pest-control agents (Gurr et al. 1998; Landis et al. 2000, Nicholls and Altieri, ch. 3 this volume). Field margins are an important type of habitat that provides refuge and resources for many arthropods. Thus field margins play a key role in maintaining biological diversity on farmland (Fry 1994). In addition, it may be useful to combine these semi-natural habitats with low-input agriculture to enhance effects on fauna diversity and natural pest control (Pfiffner 2000; Pfiffner and Luka 2003). Some habitat manipulation options are known to improve pest control in adjacent production systems. These include grassy beetle banks (Thomas and Marshall 1999; Collins et al. 2002); weedy strips; set-aside strips and field margins (see overview Marshall and Moonen 2002). This chapter focuses on the use of sown wildflower strips (a synonymous term for weed strips) which may be located in field margins. These are used to augment natural enemies and to increase the diversity of flora and fauna in annual and perennial cropping systems. One of the first initiatives to implement strip farming with sown wildflower strips in practice was taken by Nentwig (1989). Since 1993 this type of field margin has been encouraged and subsidised in the Swiss agri-environmental programs. Nowadays, more than 3000 ha of wildflower strips (in general with a width of 3–10 m) exist on farms all over Switzerland (Anonymous 2003). This chapter will detail how these strips are composed and how they can be established and managed in practice. Finally, their effects on natural enemies and pest control in annual and perennial systems are discussed.

Genetically Engineered Crops and Pesticide Use in the United States: The First Nine Years

Abstract: This report builds on earlier data and analysis funded by the Leopold Center that covered the first eight years of commercial use of genetically engineered crops. More recent reports are available at The Organic Center.

Organic Matter and Nitrogen Conservation in Manure Compost for Organic Agriculture

Abstract: Compost is a main source of organic matter (OM) and of nitrogen for organic farming in arid and semiarid regions. An effort has been made to reduce nitrogen loss during composting of separated cow manure (SCM) using high C/N additives — wheat straw, (WS), grape marc (GM) and slightly acidic additive such as orange peels (OP). The resulting composts contained 2.63%, 2.84% and 2.39% N for the GM-SCM, OP-SCM and WS-SCM, respectively. Values of N loss from the raw mixtures were 18%, 5% and 2% for the three compost types, respectively. OM values were 70%, 57% and 53% for the three compost types, respectively. Nutritional contribution of the composts was assessed using cherry tomato as a test plant, growing in the composts as growing media. Peat moss served as a control medium. The media were either unfertilized or fertilized with guano. Plant responses suggest that growth is mainly affected by nitrogen availability while flower production and fruit set is also affected by potassium availability. It was found t...

Plant Development and Harvest Yields of Greenhouse Tomatoes in Six Organic Growing Systems

Abstract: Problems concerning the environmental impact of agriculture have led to a reassessment of the conventional practices used since the 1940s, and a renewed interest by growers in organic farming began during the 1980s. Consumer interest has also increased dramatically, both for health and environmental reasons (Greene, 2000; Lampkin, 1990; Uri, 1999). Since 1996, surveys of natural food wholesalers and retailers indicated that organic produce sales had increased ≈20% yearly (Dimitri and Richman, 2000; Greene, 2001; Greene et al., 2001). Certified organic produce typically commands a higher price than conventionally grown produce. A recent survey of North Carolina-based natural food retailers and wholesalers indicated that buyers were willing to pay up to 25% more for organically grown vegetables (Estes et al., 1999). As a result of all these factors, an increasing number of growers are considering the use of, or are already employing, organic production methods. Barriers to organic certification are particularly high for greenhouse vegetable growers because virtually no technical information is available. Practices used by an experienced greenhouse organic grower to grow plants in soil have been documented (Grubinger, 1999), but specific practices for injecting fertilizer in the drip irrigation lines were not adequately described. Several grower-formulated mixtures for organic transplant production have been described (Smith, 1994), but there is little or no documentation on how to prepare organic mixes for recirculating hydroponic systems or how to add composts to soilless media used for crop production. Compost teas can be used for drip irrigation in certified organic production. However, in a manual describing the use of compost teas, Ingram and Alms (1999) describe work on compost teas as being in its infancy. The beneficial effects of compost teas were demonstrated, but most testing was conducted by trial and error. This is also true of studies using organic composts as ingredients in potting mixes and in many cases, media and waste characteristics were not reported in detail. In Germany, effluent from a fish farming unit was brought into a hydroponic cucumber (Cucumis sativus L.) and tomato greenhouse as a substitute for some of the normal fertilization (Drews and Rennert, 1992). In this study, the amount of fertilizer added to the hydroponic system was reduced by 16% for N, 14% for P, and 12% for K. Although a few examples of the successful use of organic materials in greenhouse vegetable production have been documented, it is hard to extrapolate findings to other crops and media. Broiler litter has been tested as a potting component for lettuce (Lactuca sativa L.) (Flynn et al., 1995). There are also examples where system components were well described. Tyler et al. (1993a, 1993b), Kraus et al. (2000), and Kraus and Warren (2000) conducted a series of studies of the effects of composted poultry litter on growth of containerized nursery crops. These studies described the chemical and physical characteristics of litter when combined with a pine bark substrate. However, as nursery crops grow more slowly than tomato crops, their results cannot be directly applied to a greenhouse tomato production system. Since there are no generally accepted recommendations or guidelines specifically for organic production of greenhouse tomatoes, this study was designed as a systems research project. As such, management practices for each growing season utilized information gathered from the previous growing season(s) to optimize practices for each system. The objectives of this study were to discover methods to produce healthy and productive tomato plants using flowable organic fertilizers, determine formulations for such fertilizers, and develop an organic growing medium that promotes healthy and productive tomato plants. The goal of this research project was to develop a certifiable organic regimen for growing greenhouse tomatoes that would be comparable with those grown conventionally with regard to production methods, as well as nutritional status in leaf tissue, plant development, and harvest yields.

Organic farming and measures of European agricultural policy

Abstract: This book analyses the impact of the Agenda 2000 reform on the Common Agricultural Policy on organic farming - as one of the most established examples of environmentally freindly farming systems. The authors provide comparative assessments of the impact of first and second pillar measures on conventional and organic farms, analysing the impacts of direct payments, price support measures (agri-environmental measures, investment support, processing and marketing measures, training measures and Less Favoured Area support) for a range of countries and farm types. Finally, an outlook of possible effects of the CAP Reform 2003 on organic farming systems and recommendations on how to maximise the positive effects of agricultural policy on organic farming are given. This book provides policy makers, the private sector, researchers and students in the field of general and organic agricultural policy with the most comprehensive quantitative and qualitative evaluation of support for organic farms in the EU within the Agenda 2000 framework.

Organic: is it the future of farming?

Abstract: In its pure form, maybe not. But elements of the organic philosophy are starting to be deployed in mainstream agriculture. Nature's reporters analyse this trend, assess the extent of organic farming worldwide, and frame the questions on which its wider adoption will depend.

Evaluating the benefits of organic farming in rice agroecosystems in the Philippines

Abstract: Organic rice farming utilized only 33% (39 USD ha−1) of the cash capital required to grow a hectare of rice when compared with conventional farm which spent 118 USD ha−1. This much reduced cash capital expense in organic rice farming relieved women from the burden of sourcing credit to finance crop establishment. Women are in-charge of family finances. Cooperation among members of the family (husband, wife, children) enabled them to cope with the increased labor requirement of organic farming–as in spreading rice straw, preparing and applying compost, hand weeding and picking-up golden snails. All organic rice farmers who participated in the study were members of farmers organization and/or cooperative while only few conventional farmers' were members of farmers' organization. Organic farming improved the soil quality. The paddy soil was loose and had deeper mud which was attributed to the higher soil organic matter (SOM) accumulating as a result of crop residue recycling at 3-4t ha−1 and animal ...

Growth and Oil Production of Fennel (Foeniculum vulgare Mill): Effect of Irrigation and Organic Fertilization

Abstract: Seeds of the aromatic plant fennel (Foeniculum vulgare Mill) were sown in sandy soil with 0 or 2.5 kg m−2 of organic fertilizer (OF); chicken manure, cattle manure or plant compost. Plants were irrigated two, three, four, five or six times at 21-day intervals commencing 21 days after sowing and continuing until harvest. Increasing the number of irrigations and application of organic fertilizers significantly delayed harvesting. Water stress imposed by restricting the number of irrigations significantly decreased plant height, branch number, and fruit and oil yield, whereas it increased the percentage volatile oils. All organic fertilizers increased plant growth and yield parameters. With or without organic fertilization, the increase in fruit yield with irrigation outweighed the decrease in volatile oil percentage, so volatile oil yield increased with irrigation. However, there was no significant difference in volatile oil yield between five and six times irrigated plants under any type of fertil...

Crop-livestock systems: old wine in new bottles

Abstract: Many farmers in tropical and temperate countries manage a mix of crops and animals. In these systems crop residues can be used to feed the animals and the excreta from the animals as nutrients for the crops. Other forms of mixing take place where grazing under fruit-trees keeps the grass short, where manure from pigs is used to 'feed' fish in a pond or where young animals bred in remote areas are fattened near urban centres with high demands for meat. In addition, inclusion of livestock alters the rate of nutrient turnover, it provides a labour opportunity in slack times for crops and adds value to crop (by-)products. Livestock thus affects the socio-economic and biophysical dynamics of the entire farming system. Indeed, a wide variety of forms and processes in mixed farming are known world-wide. To different degrees they are all essential for the livelihood of farmers and for the production of food and other commodities for cities and export markets. More recently, even highly specialised crop and livestock systems in developed and developing countries have rediscovered the advantages of mixed farming. Specialised industrial pig and poultry farmers have been banned from densely populated countries such as Singapore, and in Western Europe they are obliged by law to exchange their dung surpluses with crop farmers. Moreover, the essence of many modern organic farming systems lies in the mixing of crops and animals. This paper discusses the advantages and disadvantages of crop-animal systems; it presents concepts from modern system thinking that are useful for understanding the variability in crop-animal systems. The paper also provides classifications of these systems to show that opportunities for crop-animal systems exist in low and high input systems. Media summary Crop-livestock systems play a major role in the dynamics of many agricultural systems. They occur in many forms and they allow more efficient use of resources than specialized systems and spreading of risks. The renewed interest in such systems to mitigate the negative (mainly environmental) impact of highly specialised agricultural systems is highlighted.

Urban Organic Farming in Austria with the concept of Selbsternte ("self -harvest"): An agronomic and socio-economic analysis

Abstract: In Vienna, consultants, organic farmers and green-minded consumers have developed a new concept of urban organic farming, called Selbsternte (‘self-harvest’). Organic farmers prepare a plot of arable land (the Selbsternte plot) and sow or plant rows composed of 18‐23 plant species. In mid-May the plots are divided into subplots that contain 2‐6 m of every sown species and are rented to so-called self-harvesters for a period of about 136 days. In 2002 Selbsternte was being practiced at 15 plots in Vienna or in neighboring cities, represented by 861 subplots, with a total area of 68,740 m 2 , and managed by 12 organic farmers for 861 registered self-harvesters. At the Roter Berg plot, experimental subplots were established to evaluate yields and the value of the harvested produce, and interviews were conducted with 27 self-harvesters, the eight Selbsternte farmers and one Selbsternte consultant. The experimental subplots were managed in two different ways, namely, ‘with low intensity’ (LIS) and ‘with high intensity’ (HIS; meaning additional harrowing, mulching and sowing of additional plants). At the LIS 24.2 h and at the HIS 38.9 h of work were invested over 51 days. Monetary investment was US$184 for the LIS and US$259 for the HIS subplots. The total harvest of fresh produce was: 163 kg subplot ‐1 for LIS and 208 kg subplot ‐1 for HIS subplots. The total value of the harvest at the HIS was US$364 for conventional and US$766 for organic prices. All self-harvesters saw the rental of a subplot and the work as an activity of leisure. More than half of the self-harvesters reported ‘trying something new’ at their subplots. The most frequently mentioned innovation for them was growing an unknown species. Twenty-five self-harvesters sowed 54 different, additional plant species. The motivating factors in establishing Selbsternte plots, as reported by all the farmers, were, primarily, better relations with consumers and work diversification, and only then were economic factors a consideration. The contribution of Selbsternte to income varied at the farms, being between 0 and 30% of the total farm income. As a main success factor, all of the farmers reported a close relationship between the self-harvesters and the farmers. Selbsternte subplots can be understood as small experimental stations where self-harvesters merge traditional horticultural techniques with urban ideas on permaculture, sustainable land use and participatory farming. Selbsternte has potential value for the improvement of urban agriculture, but also for the development of organic farming in general.

LOCALISATION AND CONCENTRATION OF ORGANIC FARMING IN THE 1990s – THE DANISH CASE

Abstract: This study explores the localisation of organic farms in Denmark for the three years 1994, 1997 and 2001, on a county and parish level. Spatial concentration is found in counties with a high share of milk producers, but also in the counties, which contain the two largest urban centres. General regional specialisation of the agricultural sector in Denmark contributes to the explanation of concentration patterns of organic conversion, but other factors like a regional favourable policy climate and -support also appear to play a role. Major variations in concentration within regions are found, suggesting that local factors play an important role for the explanation of spatial patterns of organic conversion.

Organic farming and agroforestry: Alleycropping for mulch production for organic farms of southeastern United States

Abstract: Organic farming offers an alternative that can eliminate many of the environmental problems of conventional agriculture in the industrialized world. Instead of using petroleum-derived chemicals to fertilize and protect crops, farmers manage their fields so as to take advantage of naturally-produced composts and mulches that recycle nutrients, and control pests and weeds. However, organic farming is often logistically inefficient, because these organic composts and mulches are bulky and difficult to transport. Alleycropping as practiced in the tropics may be able to make organic farming more efficient in the southeastern United States. In this form of alleycropping, trees or shrubs, often leguminous, are planted in hedgerows between open spaces (‘alleys’) where the crop is grown. The hedgerow species are periodically pruned (both aboveground and belowground), and prunings fall directly onto or into the soil where the crop is growing. These prunings add carbon and nutrients to the soil, and provide mulch that helps suppress weeds. Use of prunings reduces the need for composting and hauling manures and mulches, thereby increasing the efficiency by which organic material is supplied to the soil that supports the economic crop. In Georgia, dry weight annual production of prunings reached up to 18.4 Mg ha−1, a quantity high enough to maintain crop production. Thus, alleycropping may be feasible for organic farmers in the southeastern United States.

Sustaining animal health and food safety in European organic livestock farming.

Abstract: Abstract In Europe, organic livestock production has experienced a rapid growth in the past decade, which has produced many challenges for the animal food production system. Whilst emphasising the importance of a systems approach to animal health and welfare protection, organic livestock production standards place considerable restrictions on the use of many animal health inputs that are routinely used in conventional production systems. Recommended practices in the European Organic Livestock Standards (EU Regulation 1804/1999), such as closed herds and flocks and improved health security on farms, also include extensive production systems (e.g., free range production) that expose livestock to increased disease challenge. Organic livestock production faces major challenges with regard to harmonisation and successful integration of organic animal husbandry into the whole organic production system. Major questions about food quality and safety exist. Significant diversity between farming systems between different countries in Europe, including candidate countries, should be taken into account in developing farming systems that all comply with common EU standards, but are in harmony with their geographic and cultural localities. A newly initiated EU network project ‘Sustaining Animal Health and Food Safety in Organic Farming’ (SAFO), with 26 partners in Europe, focuses on the integration of animal health and welfare issues with food safety aspects. This network and some of the key questions in focus in this network are presented in this paper.

Nutrients in organic farming - Are there advantages from the exclusive use of organic manures and untreated minerals

Abstract: Nutrient additions on organic farms are designed to maintain soil fertility, but not to directly feed plants. Hence, nutrients are applied in organic or low solubility inorganic forms in the belief that plants will obtain balanced nutrition through the actions of soil microbes. This review examines the implications of organic farming fertiliser practices for the sustainability of farming systems using two contrasting regions, Europe and Australia. In both these regions, mean yields are generally 20-45% lower on organic farms than conventional farms primarily due to reduced levels of plant available nutrients. Changes in the soil biological community do not overcome this limitation. Nutrient inputs are lower on organic farms, although in Europe there is a tendency on organic farms for increased application of purchased, approved, nutrient sources other than fodder. However, these inputs simply allow organic farms to gain nutrients that originated from conventional farms. If organic farming were to be widely adopted, lower yields would require more land (25-82%) to sustain production. In Europe, organic practices increase nitrate leaching, both per unit area and per unit of food produced, due to lower N use efficiency. Despite their aim of maximizing nutrient recycling, organic farming systems recycle only on-farm wastes and approved food wastes, with most municipal wastes excluded due to concerns about pollutants. In future, easily soluble inorganic fertilizers will be extracted from organic wastes through new nutrient recovery technologies and this will make conventional agriculture more sustainable whereas organic farming excludes itself from non-farm recycling, no matter how environmentally clean and safe the new fertilizer products are. In conclusion, the current promotion of organic principles irrespective of environmental outcomes means organic farming has become an aim in itself. This approach is ideological, not scientific, and may exclude other more effective solutions to the environmental problems afflicting current agricultural systems.

Mycorrhizal colonization of flax under long-term organic and conventional management

Abstract: Arbuscular mycorrhizal fungi are of particular interest in organic agricultural systems. We studied the effects of crop rotation and crop management system (conventional vs. organic) on mycorrhizal colonization of flax roots, in the 12th year of a long-term crop rotation trial. Colonization was higher in organic treatments than conventional, possibly due to decreased P availability. There was a highly significant rotation × management system interaction, which may be explained by differences in the abundance of mycorrhizal and non-mycorrhizal weed species between the two management systems. Further research is required before stronger conclusions can be made. Key words: Crop rotation, arbuscular mycorrhizal fungi, flax, wild mustard, host-plant dynamics, organic agriculture