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Organic farming is continuing to expand in Canada, with close to 6,000 producers farming over 2% of all agricultural land. There is insufficient evidence, however, of a trend toward larger average farm size and increasing specialization by these organic farms. This mini-review postulates that a gradient of intensity of farm management exists within organic farming sectors in Canada, with respect to cropping diversity, and tillage and nutrient utilization, and this gradient of intensity is a key determinant of agroecological outcomes. This variation in management approach and intensity reflects producer's individual perspectives on organic farming principles and practices, irrespective of farm scale. By directly influencing farm crop and vegetative diversity and cover, and farm nutrient status and carbon cycling, management intensity determines soil carbon storage and flux, soil health and biodiversity agroecological and ecosystem services, plus farm agronomic resilience. Demographic trends and perspectives of new entrants in organic farming are encouraging signs of an increasingly inclusive and socio-ecologically complex Canadian organic farming sector, which recognizes the agroecological implications of intensity of organic farm management across all production sectors.

Organic field crop systems are characterized by complex rotations with high spatial and temporal vegetative diversity, an enhanced use of legumes, and reduced external nutrient (nitrogen (N) and phosphorus (P)) use. At the same time, a core premise of certified organic agriculture is that this farming system provides benefits to soil health via enhanced microbial diversity. The following short review, drawing primarily upon selected studies from North America, examines the impact of farming systems, and various management strategies within these, on soil organic matter, N and P dynamics, and soil microbial and macrofaunal abundance and diversity. Organic cropping systems are shown to provide benefits with respect to reduced farm N and P surpluses, in combination with maintenance of soil organic matter and improved soil health. However, soil health benefits appear consistently achieved only for larger soil organisms partly due to the resilience of the soil microbial community. Recent research examining soil P dynamics and P uptake in relation to legume biological N2 fixation and bacterial and mycorrhizal community diversity provide evidence of the resilience of the soil microbial community with respect to functionality, if not diversity of microbial community composition. These latter results may challenge organic agriculture core premises of consistent benefits to soil health via enhanced microbial diversity, but in its place may lead to an improved understanding of how specific cropping practices and production system intensity overall, rather than farming system per se, influences both nutrient cycling and soil ecosystem functioning.

Dalotia coriaria (Kraatz, 1856) (For diagnosis, illustrations and literature reviews, see Klimaszewski et al. (2007) and Gouix and Klimaszewski (2007)). CANADA, Nova Scotia, Upper Rawdon, Hants Co., 14.VIII.2008, highbush blueberry field R2T3A, J. Renkema (CGMC) 1 male. Dalotia coriaria is a cosmopolitan species that is adventive in many parts of the world including Europe, east Africa, Madagascar, New Zealand, Galapagos Islands (Benick and Lohse 1974; Pace 1999; Sivasubramaniam et al. 1997; Klimaszewski and Peck 1998), and North America (Klimaszewski et al. 2007). In Canada it has previously been recorded from Ontario and Alberta (Klimaszewski et al. 2007; Gouix and Klimaszewski 2007), and in the United States from California, Florida, Louisiana, Massachusetts, New Jersey, and New York (Moore and Legner 1975; Muona 1984; Frank 1980; Gusarov 2003). Th is species is herein newly recorded from Nova Scotia., Published as part of Klimaszewski, Jan, Lynch, Derek, Majka, Christopher, Renkema, Justin, Savard, Karine & Hlavac, Peter, 2009, Pella glooscapi, a new rove beetle, and new records of aleocharines from Nova Scotia, Canada (Coleoptera, Staphylinidae), pp. 35-44 in ZooKeys 22 (22) on page 42, DOI: 10.3897/zookeys.22.95, http://zenodo.org/record/576534, {"references":["Kraatz G (1856) Staphylinii. Naturgeschichte der Insecten Deutschlands. Vol 2. Nicolai, Berlin: 1 - 376.","Klimaszewski J, Assing V, Majka CG, Pelletier G, Webster RP, Langor D (2007) Records of adventive aleocharine beetles (Coleoptera: Staphylinidae: Aleocharinae) found in Canada. Th e Canadian Entomologist 139: 54 - 79.","Gouix N, Klimaszewski J (2007) Catalogue of Aleocharine Rove Beetles of Canada and Alaska (Coleoptera, Staphylinidae, Aleocharinae). Pensoft Publishers, Sofia-Moscow, 166 pp.","Pace R (1999) Insectes Coleopteres Staphylinidae Aleocharinae. Faune de Madagascar, Paris 89: 1 - 261.","Sivasubramaniam W, Wratten SD, Klimaszewski J (1997) Species composition, abundance, and activity of predatory arthropods in carrot fields, Canterbury, New Zealand. New Zealand Journal of Zoology 24: 205 - 212.","Klimaszewski J, Peck SB (1998) A review of aleocharine rove beetles from the Galapagos Islands, Ecuador (Coleoptera: Staphylinidae, Aleocharinae). Revue suisse de Zoologie 105: 221 - 260.","Moore I, Legner EF (1975) A catalogue of the Staphylinidae of America north of Mexico (Coleoptera). University of California Division of Agricultural Sciences, Special Publication 3015: 1 - 514.","Muona J (1984) Review of Palaearctic Aleocharinae also occurring in North America (Coleoptera: Staphylinidae). Entomologica Scandinavica 15: 227 - 231.","Frank JH (1980) Atheta coriaria (Kraatz) (Aleocharinae) and Sunius confluentus (Say) (Paederinae) in Florida (Coleoptera, Staphylinidae). Th e Coleopterists Bulletin 34: 388.","Gusarov VI (2003) Revision of some types of North American aleocharines (Coleoptera: Staphylinidae: Aleocharinae), with synonymic notes. Zootaxa 353: 1 - 134."]}