Organic farming

About: Organic farming is a research topic. Over the lifetime, 7254 publications have been published within this topic receiving 138030 citations. The topic is also known as: pertanian organik & organic farming.

Influence of cropping system on harvest erosion under potato

Abstract: Cultivation of potato may cause water erosion, wind erosion, tillage erosion and harvest erosion. Little is known about extent and driving forces of harvest erosion, which is the loss of soil by imperfect soil–tuber separation during harvest. We examined the extent of harvest erosion on different scales from plot over field and farm to landscape scale and at different stages of soil–tuber separation from unassisted harvested over assisted harvested, on-farm cleaned, graded to packaged potatoes. On plot scale the influence of cropping practices to lower water erosion was examined with five treatments on three sites over 5 years. On field and farm scale we examined two farming systems (organic versus conventional) on 17 fields covering 5 years. On landscape scale we compared two landscapes over 9 years. Soil losses per harvest were in the same range as can be expected annually for water erosion averaging 8 t ha −1 in plot experiments, 6 t ha −1 on field scale and 2 t ha −1 on landscape scale. The losses decreased drastically with increasing potato processing from 8 t ha −1 with unassisted harvesting to 0.1 t ha −1 for graded and packaged potatoes. Cultivation technique had no influence. This allows applying measures to reduce water erosion without adverse effects on harvest erosion. Farming system exerted a dominant influence on field and farm scale with an average loss on field scale of 8 t ha −1 for conventional and only 3 t ha −1 for organic farming. About half of the variation in harvest erosion on plot and field scale could be described by two planting conditions (rain in March and type of farming) while the remaining variation was caused by harvesting conditions. Harvesting conditions leading to high losses were manifold (e.g. very dry or very wet soil, heavy weed infestation) and could not be described by general relations. On landscape scale planting conditions leveled out and soil and weather conditions during harvest explained 95% of the variation. Losses were higher in years with rainy autumns and in the coarse-loamy landscape because soil shrinkage upon drying improved on-farm soil–tuber separation in the fine-loamy landscape. For highly processed potatoes (graded, packaged) properties of the tuber (specific surface area) exerted a strong influence. Harvest erosion under potato is an underrated process contributing significantly to total soil loss. The extent is lower under organic than conventional farming and can further be largely influenced by on-farm post-harvest processing of the potatoes returning the removed soil to the field where it originated from.

Reconciling scientific approaches for organic farming research

Abstract: Part I : Reflection on research methods in organic grassland and animal production at the Louis Bolk Institute, The Netherlands Key words: organic agriculture, anthroposophy, methodology, research strategy, experiential science, multidisciplinary science, Goethean science This dissertation focuses on the research question: what is peculiar to agricultural research when its purpose is to support the conscious development of organic agriculture? What approaches, designs and methods are used for such research? Since the 1990s the Louis Bolk Institute has become one of the important actors in the field of organic research and development. The author analysed the methodological aspects of seven case studies, each following the same format: background of the project, methods used, a reflection on the methods and, to a limited extent, agronomic results. Each of these sheds light on an aspect of the Louis Bolk Institute's approach to research. Organic farming is experienced as a new paradigm and its research methods need to do justice to it. Three criteria were formulated for this purpose: the self regulation of farming systems, the involvement of farmers and the respect for the integrity of life. Two conceptual frameworks are used to analyse the research methods: (1) a four-quadrant matrix. Epistemological, ontological and methodological changes in the way of thinking are relevant in discussions about holism versus reductionism and positivism versus constructivism. The second framework is (2) a triangle which can show the relationship between the underlying values, the involvement of the actors and the nature of the scientific process. The scientific position which is defended in this dissertation can ultimately best be described as a 'radical holistic research strategy'. Research approaches applied in the case studies are: interdisciplinary research, experiential science and mutual learning, farmer-to-farmer learning, exploring tacit knowledge, bio-ethical evaluation, Goethean science and systemic development. In the four quadrant matrix two new additional research methods are positioned: (1) Goethean science is included as a holistic counterpart to multidisciplinary system ecology; (2) experiential science is included for comparison with mono-disciplinary experimental research. The constructivist character of both Goethean science and experiential science particularly distinguishes these methods from mainstream science. The meta-reflection on the research showed some important new elements of research. There was a systemic orientation in terms of a cohesive set of management measures and actions. This systemic orientation also encompasses holism in terms of Goethean science. In addition there is the experiential science based on intuitive action and pattern recognition. The reflection on the methods made it clear that their acceptance was influenced by the underlying scientific philosophy. The entire research strategy is thus based on two different interpretations of knowledge. Experiential science focuses on the actions of the farmer and is based on the epistemology of action. In addition there is an epistemology of knowledge, where it relates to interdisciplinary research and Goethean science. There are barriers to the acceptance of these scientific methods in the current lack of suitable statistical evaluation methods, and also in the absence of accepted methods for explicitly exploring reality as constructed by people. Part II : Effects of manure types and white clover (Trifolium repens) cultivars on the productivity of grass-clover mixtures grown on a humid sandy soil Key words: organic agriculture, grass-clover, white clover cultivars, animal manure, potassium, nematodes, earthworms This Part describes the agronomic results of the multidisciplinary grassland study. This project concerned the effects of clover varieties and spring applications of animal manure on the yield of grass-white clover mixtures on a moist sandy soil (1993-1996). To be aware of the context of the findings in a multidisciplinary approach, attention was paid to: chemical soil fertility, damage to clover by slugs and soil borne nematodes. To increase the understanding of soil fertility, earthworm dynamics were also measured. At the end of the period the botanical composition of all plots was assessed. Factors measured besides total yield and clover yield were N, P and K yield. It was found that these 'context'- measurements were important for the overall explanation of the scientific results. Data were used for modelling several relationships between yield parameters. The overall findings of this project led to an understanding and description of the main aspects of manure with regard to grass-white clover growth on a moist sandy soil. It was concluded that on a moist sandy soil the amount of inorganic and organic N, the N release and the K input were the main manure factors relating to fluctuations in total yields on white clover development and on N yields in the first six years after sward establishment. The inorganic N component in manure can be used strategically to improve the growth of the herbage in spring. Maintenance of soil fertility in terms of P, K and Ca levels is an important key factor for a successful organic grass-clover sward. Carbon rich FYM derived from a deep litter stable and composted before application increased the earthworm population, reduced the number of nematodes and maintained the highest level of soil pH, all factors which might positively affect white clover growth in the long term. FYM applied in spring resulted in the typical extended growth season in the second part of the growing season. On a sandy soil the high concentration of K in the FYM positively affects the potential white clover growth. The choice of a persistent white clover cultivar is another important factor affecting herbage and N yields of an organic grass-clover sward. However, winter losses were not found to be the main cause of white clover reductions over the years. Losses in the growing season were related to slugs which reduced white clover leaf area. The literature shows that the cyanide concentration in DM herbage affects the susceptibility of white clover to pests.

Change of the Weed Seed Bank during the First Complete Six-Course Crop Rotation after Conversion from Conventional to Organic Farming

Abstract: The modification of the weed seed bank in the top soil (0–20 cm) during a six-year period including a sequence of annual crops and a perennial grass-clover ley in the rotation, were analysed in an organic cropping system after conversion to organic farming. The seed bank of dicotyledonous annual species varied from a minimum of 7200 seeds m−2, the year following a three-year period with perennial ley, to a maximum of 17600 seeds m−2, the year following a three-year period with annual crops. The number of species in the seed bank was essentially constant at 18–21 during the rotation, but the number of emerged species in the field decreased from about 19–20 during the annual crop period to a minimum of eight in third year ley, indicating a reduced input of seeds to the seed bank during the ley period. Dicotyledonous perennial weed seeds in the soil constituted only 2–3% of the seed bank. The correspondence between the soil seed bank and emerged weed plants was not straightforward. For Capsella burs...

Organic production of vegetables: State of the art and challenges

Abstract: In light of the growing concern of Canadians about animal waste, environmental pollution from fertilizers, water quality and greenhouse gas effects, as well as their growing interest in organically grown foods (20% annual growth in North America), the development of sustainable organic production systems for vegetable crops is essential for consumer satisfaction and Canadian grower competitiveness. The target of this paper is to review recent research results on the importance of appropriate soil properties, fertilizers and irrigation management on soil activity, plant growth and environmental health as well as product quality in term of nutritional value and safety issue. Species and cultivar selection, the use of grafting and plant growth promoters will also be discussed. This review will identify new challenges that organic growers have to fulfill in the face of a global market and public awareness of health attributes of food, and then conclude by identifying several prospects for future research with...