nfluence of nitrogen fertilization on abundance and diversity of plants and animals in temperate and boreal forests,Environmental Reviews, https://doi.org/10.1139/er-2017-0026

ABSTRACT: Aerial and land-based applications of nitrogen-based fertilizers to enhance forest growth makes nutrients potentially available to all trees, plants, and wildlife in a given ecosystem and, therefore, may have direct and indirect effects on wildlife and biodiversity. A scientific review of these potential effects was conducted with 106 published studies covering vascular and nonvascular plants, amphibians, birds, mammals, terrestrial invertebrates, and soil animals associated with fertilization in temperate and boreal forests, primarily in North America and Scandinavia. In terms of direct effects, amphibians and domestic mammals appear to be the most sensitive to urea used in fertilization programs. The avoidance behaviour and (or) mortality of amphibians in laboratory studies was species dependent. Ruminant animals, including wild ungulates, rapidly convert urea to ammonia and are susceptible to toxicity following ingestion of large amounts of urea. Feeding on urea pellets by small mammals or gallinaceous birds appears to be minimal as granules are unpalatable. In terms of indirect effects, the majority of responses of understory herbs to nitrogen fertilization showed an increase in abundance. Some shrubs in repeatedly fertilized stands eventually increased in abundance in long-term studies, whereas dwarf shrubs and abundance of bryophytes (mosses and terrestrial lichens) declined. In general, species richness and diversity of understory herbs and shrubs declined, or were unaffected, in fertilized stands. Response in abundance and species richness-diversity of vascular plants to a single application of nitrogen showed either an increase or no change. Repeated applications (2–5 and >5) usually resulted in declines in these responses. Relative abundance of mule deer (Odocoileus Rafinesque spp.), moose (Alces alces L.), and hares (Lepus L. spp.), and forage quantity and quality were usually increased by fertilization. Small mammal species generally showed increases or no change in abundance; decreases may be related to fertilizer-induced changes in food sources. Forest fertilization may provide winter feeding habitat for coniferous foliage-gleaning insectivorous birds in some cases. Six species of forest grouse showed no response to fertilizer treatments. Responses of soil animals to nitrogen fertilization appeared to be species- and dose-specific and are ameliorated by surrounding micro- and macro-habitat characteristics.

Please find enclosed some interesting studies...

Thank you for the interesting publications! The publication from the Netherlands (De Goede et al. 2003) was new to me. However, this study was done on grassland. I would be also interested in information from agricultural fields (wheat, corn, ...).

Soil biodiversity is often considered an essential element in sustaining ecosystem services in agricultural systems. Understanding functional biodiversity with respect to its impact on nitrogen mineralization and retention might, therefore, contribute to more sustainable production and prevention of environmental complications. Significant decrease in the abundance of Enchytraeidae, Collembola and Crypto stigmata after ammonium nitrate fertilization observes. A shortterm effect with decreased abundance owing to ammonium toxicity or a "salt effect". A long-term effect with increasing abundance resulting from increased food supply.One objective in organic farming is to sustain the quality of the soil resource. Because enchytraeids are an important soil faunal component, they stand as bioindicators of soil quality. We tested this candidature in a field experiment on loamy sand soil with 1- and 4-year old grass-clover leys subject to contrasting management regimes (cutting, slurry injection, grazing). Enchytraeid density, biomass and species composition was determined in 0–18 cm soil sampled in October, and again in March and May before and after slurry application, respectively. For soils retrieved in October, ley age had no consistent impact on enchytraeid density and biomass. Injection of slurry significantly affected the enchytraeid community at one sampling only but tended to sustain higher enchytraeid abundance in 1-year old leys throughout the year. One persistent feature was a larger enchytraeid community in the autumn than in the spring, regardless of management regime. Compared with leys used for cutting, grazed leys had consistently lower enchytraeid density and biomass. This was ascribed to soil compaction induced by heifer trampling. The number of species ranged from 11 to 18 in the autumn and from 7 to 13 in the spring with no distinct relation to management. Simpson's index of diversity did not differ among sampling dates and management regimes, including ley age. Although the enchytraeid community to some extent reflected differences in management regime, the patchy distribution and management induced interactions among soil physical, chemical and biological properties suggest that enchytraeid abundance is not a feasible stand-alone indicator of management impacts on soil quality in temporary grass-clover leys but may candidate as one of several biological key parameters in more comprehensive soil quality assessment schemes.

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Thanks to all of you for sharing the interesting publications!