Juha Helenius

Agroecology: The Ecology of Food Systems

ABSTRACT We present a compelling rationale for defining agroecology as the ecology of food systems. Our purpose is to provide a framework that will guide research, education, and action in the multiple and interacting facets of an increasingly complex global agriculture and food system. To accomplish such goals, it is essential to build bridges and connections among and beyond our disciplines in production agriculture, as well as beyond the farm gate into the rural landscape and community. Fields of sociology, anthropology, environmental sciences, ethics, and economics are crucial to the mix. They provide additional vantage points from which we can view the food system anew, as well as insights on how to establish valuation criteria beyond neoclassical economics. Examples from Mexico, California, and the Nordic Region are used to illustrate the successful implementation of this educational strategy in universities. Design of individual farms using principles of ecology is expanded to the levels of landscape, community, and bioregion, with emphasis on uniqueness of place and the people and other species that inhabit that place. We conclude that defining agroecology as the ecology of food systems will foster the development of broader interdisciplinary research teams and attractive systems-based courses for tomorrows best students. In contrast to the narrow focus on crop-soil interactions, this definition will help us raise higher-level research questions whose solutions will advance the development of a sustainable agriculture and food system.

Revisiting the species-area relationship in a semi-natural habitat: floral richness in agricultural buffer zones in Finland

Abstract Buffer zones in agroecosystems are maintained to prevent soil erosion, nutrient leaching and pesticide drift from arable fields. Buffer zones are also semi-natural habitats supporting wildlife in farmland. At the landscape level, buffer zones may also function as corridors in agricultural mosaics. This study aims at understanding the relationship between spatial structure of buffer zones and floral species richness. These are linear landscape elements for which the area is approximated by the product of length and width. The species–area relationship ( S = cA z ) was revised, accordingly, and it was found that patch width was the most effective spatial indicator for species richness in buffer zones. The modified species–area model emphasised the species–area relationship and the importance of width in buffer zone design in an agricultural landscape. It was concluded that there is no unique best-fit model of species–area for both natural and semi-natural ecosystems. Especially in agricultural landscapes, in which habitat heterogeneity is introduced by agricultural activities, the species–area model must be reconsidered accordingly. Some possible factors accounting for the results were discussed. It was suggested that the increase in species diversity with an increase in width of the buffer zone may be due to cross-sectional habitat gradients within the linear patches. The result can be used for optimising buffer zones to meet the needs of biodiversity conservation.

Localisation of primary food production in Finland: production potential and environmental impacts of food consumption patterns

The potential for and environmental consequences of localising primary production of food were investigated by considering different food consumption patterns, based on conventional and organic production. Environmental impact was assessed according to agricultural land use and numbers of production animals, both of which depend on food consumption. The results were quantified in terms of nutrient balances, greenhouse gas and acid emissions and the diversity of crop cultivation, which indicate eutrophication of watersheds, climate change and landscape changes, respectively. The study region was able to satisfy its own needs for all farming and food consumption scenarios. Dietary choice had a marked impact on agricultural land use and on the environmental parameters considered. Organic farming for local food production resulted in higher greenhouse gas emissions. Compared with mixed diets, the vegetarian diet was associated with lower emissions and nutrient surpluses, but also with reduced crop diversity. The arable areas allocated to leys and pastures were also smaller. The study area represents a predominantly rural region and is a net exporter of agricultural produce. Therefore, only part of the environmental impact of food production results from local needs. Both the differences among the dietary options and the overall environmental benefit of localised primary food production were greatly reduced when considering total agricultural production of the region. Much of the negative impact of agriculture is due to food consumption in the densely populated urban areas, but the consequences are mainly felt in the production areas. The environmental impacts of localisation of primary food production for the rural areas are small and inconsistent. The results indicate the importance of defining ‘local’ on a regional basis and including the urban food sinks in impact assessment.

Value of semi-natural areas as biodiversity indicators in agricultural landscapes

Abstract Semi-natural habitats are key elements between cultivated and natural areas. Ditch boundaries, buffer zones, barn areas and woodland patches were analyzed in Toholampi, Ylane, Nurmijarvi and Liperi localities in Finland over the period 1954–1998 by means of indicators for semi-natural areas, based on calculations of the sum of patch densities (PDsum) and the sum of patch areas (CAsum). There were only a few semi-natural habitats left by the late 1990s. The sharpest decrease in PDsum indicator values, by 90%, was found for Ylane, while the corresponding drops in the figures for Nurmijarvi, Toholampi and Liperi were 77, 65 and 59%, respectively. The CAsum indicator showed a similar trend. The indicators were tested by calculating the metapopulation capacity of the barn areas. The use of CAsum is suggested for semi-natural patches as a quick, cheap and robust monitoring tool and indicator of change in biodiversity value in agricultural landscapes. The indicator PDsum may be important to interpret landscape and habitat changes when attention needs to be paid to the mosaic of landscape elements.

Meat bone meal as fertiliser for barley and oat

The traditional production of mineral N and P fertilisers is unsustainable due its reliance on fossil fuels in the case of N, and on limited mineral resource stocks in the case of P. The use of alternative or complementary fertilisers that originate from organic waste materials is gaining interest. Organic farms, especially arable organic farms without livestock, need usable sources of plant nutrients. Meat bone meal (MBM), a potential organic fertiliser for agricultural crops, contains considerable amounts of nutrients (on average 8% N, 5% P, 1% K and 10% Ca). In EU countries, Commission regulation (EC) No 181/2006 authorised the use of MBM as an organic fertiliser. In this study, MBM was compared to conventional mineral NPK fertiliser. Two randomised complete block split-plot field experiments were conducted: one with spring barley (Hordeum vulgare) in two years; and another with oat (Avena sativa) for three years, including a fourth year of testing for residual effect. Compared to mineral fertiliser (20% N, 3% P and 9% K), MBM was applied at three N levels: 60, 90 and 120 kg N ha-1. The grain yield of both cereal species supported by MBM, did not differ from the yield obtained with the mineral fertiliser at any N level. At 120 kg N ha-1, the grain yield level with either type was ca. 4500 kg ha-1 of barley and 5000 kg ha-1 of oat, representing fair averages for Finnish conditions. Moreover, MBM and mineral fertilisation showed no differences in quality in terms of 1000-grain weight, test-weight, protein content and protein yield. Since MBM has a low N/P ratio, P was applied in surplus to attain comparable N levels. Therefore MBM fertilisation should be fitted for crop rotation and for meeting environmental requirements.;

Challenges in designing ecological agriculture education: A nordic perspective on change

Educators in ecological agriculture are developing learning environments that differ in three fundamental ways from conventional teaching in agricultural universities and colleges. First, increased emphasis on food and production systems will expand and complement the current focus on specific disciplines and technologies. Second, introduction of research methods and learning objectives from social sciences will broaden the potentials for students to understand the complexities of food systems and the people who make them work. Third, action research and education will move learning activities into the agroecosystems environment and the human landscape, where students will learn from a broad array of people and experiences. This design of a new learning environment will enhance the education of students to serve agricultural and food systems well into a future that is changing at an accelerating rate.

Gut contents of ground beetles (Col., Carabidae), and activity of these and other epigeal predators during an outbreak of Rhopalosiphum padi (Hom., Aphididae).

Abstract Polyphagous ground beetles were collected with pitfall traps from a spring barley field during an outbreak of Rhopalosiphum padi (L.) in southern Finland. A total of 1175 specimens belonging to 29 species of Carabidae were caught during a five-week trapping period, which gave an average of 0.68 specimens per trap day. Carabids together with staphylinids were more numerous than spiders. Bembidion guttula was the dominant species, but Clivinafossor and Bembidion quadrimaculatum also occurred abundantly during the establishment phase of the aphids. Three weeks later, during the population peak of the aphids, Bembidion spp. had declined and Amara plebeja was the most numerous species in the catch Gut dissections showed that Bembidion spp. and C. fossor had predated on R. padi just after the first colonists had arrived. Together with aphids, Collembola and other soil animals comprised the food typical of Bembidion spp. During the aphid peak, a high percentage of A. plebeja and Harpalus rufipes had con...

Toxicity of plant extracts to three storage beetles (Coleoptera).

Eleven indigenous Ghanaian plant species were tested for their toxicity to 3 storage pest species: Acanthoscelides obtectus, Prostephanus truncatus and Sitophilus oryzae under laboratory conditions. P. truncatus was reared on loose maize grains, S. oryzae on wheat grains and A. obtectus on cowpeas. All rearings were done in an incubator at 25–26°C and 65–75% R.H.

Future Education in Ecological Agriculture and Food Systems: A Student-Faculty Evaluation and Planning Process

ABSTRACT Three graduate-level short courses on ecological agriculture and food systems were held in 1995–1997 in Norway to introduce systems thinking, creative research methods, and innovative learning approaches. In 1999, a three-day evaluation and planning workshop was held to assess course impacts, to determine relative importance of content areas, to compare learning methods with special attention to case studies, and to vision and develop action plans for future education in the region. Students and faculty agreed that soft systems research methods and varied learning processes in the course were more valuable than specific technical content that can be learned in other venues. Nine priority education areas were identified for ecological agriculture: (1) systems thinking, (2) research methods, (3) farmer/stakeholder participation, (4) improving production methods, (5) relating agriculture to food systems, (6) learning about learning, (7) values and ethics, (8) faculty development and institutional change, and (9) agricultural and food policy. We explored current knowledge and future educational importance of each area, and found that case studies can integrate many of these topics. Four specific priority educational needs were identified through visioning toward an action plan for the region: (1) publish a Nordic teaching text in ecological agriculture, (2) expand the network of educators and researchers with a short course for faculty, (3) broaden the focus from farm production to food systems by including additional disciplines and themes, and (4) coordinate thesis research activities in ecological agriculture among universities. Evaluation and planning were efficient and productive in this short workshop, due to prior organization and creating ownership in the process and the future education plans, and all participants were involved in writing this final document.

Incidence of specialist natural enemies of Rhopalosiphum padi (L.) (Hom., Aphididae) on oats in monocrops and mixed intercrops with faba bean.

Field experiments were conducted in southern Finland in 1981–1985. Shoots of oat, Avena sativa, were sampled in monocrops and mixed intercrops of oats and faba bean, Vicia faba, in order to estimate the densities of bird cherry‐oat aphid, Rhopalosiphum padi, its coccinellid and syrphid predators, parasitized (mummified) aphids and aphids killed by fungal pathogens.