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Luisa NERI Fabiano SILLO Elisa ZAMPIERI Erica LUMINI Giovanni MARTURANO Chiara Degli ESPOSTI Gianniantonio PETRUZZELLI Beniamino GIOLI Alessandro ZALDEI Rita BARALDI Raffaella BALESTRINI 《土壤圈》2023,33(4):670-675
<正>Dear Editor,Soil quality is defined as“the capacity of a soil to function,within ecosystem and land use boundaries,to sustain productivity,maintain environmental quality,and promote plant and animal health”(Doran and Parkin 1994).In this context,soil functionality is fundamental to the biosphere and is highly dependent on the associated microbiota.Soil microorganisms are relevant for terrestrial ecosystem functioning,and understanding the functional changes of the biological community i... 相似文献
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Background
Herbivory can affect every aspect of a plant's life. Damaged individuals may show decreased survivorship and reproductive output. Additionally, specific plant species (legumes) and tissues (flowers) are often selectively targeted by herbivores, like deer. These types of herbivory influence a plant's growth and abundance. The objective of this study was to identify the effects of leaf and meristem removal (simulated herbivory within an exclosure) on fruit and flower production in four species (Rhus glabra, Rosa arkansana, Lathyrus venosus, and Phlox pilosa) which are known targets of deer herbivory. 相似文献94.
Roberto Borriello Erica Lumini Mariangela Girlanda Paola Bonfante Valeria Bianciotto 《Biology and Fertility of Soils》2012,48(8):911-922
As obligate mutualistic symbionts, arbuscular mycorrhizal fungi (AMF) colonize the roots of many agricultural crops, and it is often claimed that agricultural practices are detrimental to AMF. As a result, agroecosystems impoverished in AMF may not get the fully expected range of benefits from these fungi. Using molecular markers on DNA extracted directly from soil and roots, we studied the effects of different management practices (tillage and N fertilization) on the AMF communities colonizing an experimental maize field in Central Italy. Our molecular analysis based on three different nuclear rRNA regions (18S, 28S and ITS) allowed us to assess AMF biodiversity. Glomeraceae members were the main colonizer, and they co-occurred with Gigasporaceae and Paraglomus regardless of the management practices applied. Diversisporaceae and Entrophosporaceae members were instead detected in the N-fertilized soils and in the untreated soil, respectively. The results obtained indicated that the general AMF assemblages structure and composition in the maize field plots appear to be primarily influenced by N fertilization and, to a lesser extent, by tillage. This study also validates the usefulness of multiple molecular markers to consolidate and refine the assessment of the environmental AMF diversity. 相似文献
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The genome of the sea urchin Strongylocentrotus purpuratus 总被引:2,自引:0,他引:2
Sea Urchin Genome Sequencing Consortium Sodergren E Weinstock GM Davidson EH Cameron RA Gibbs RA Angerer RC Angerer LM Arnone MI Burgess DR Burke RD Coffman JA Dean M Elphick MR Ettensohn CA Foltz KR Hamdoun A Hynes RO Klein WH Marzluff W McClay DR Morris RL Mushegian A Rast JP Smith LC Thorndyke MC Vacquier VD Wessel GM Wray G Zhang L Elsik CG Ermolaeva O Hlavina W Hofmann G Kitts P Landrum MJ Mackey AJ Maglott D Panopoulou G Poustka AJ Pruitt K Sapojnikov V Song X Souvorov A Solovyev V Wei Z 《Science (New York, N.Y.)》2006,314(5801):941-952
We report the sequence and analysis of the 814-megabase genome of the sea urchin Strongylocentrotus purpuratus, a model for developmental and systems biology. The sequencing strategy combined whole-genome shotgun and bacterial artificial chromosome (BAC) sequences. This use of BAC clones, aided by a pooling strategy, overcame difficulties associated with high heterozygosity of the genome. The genome encodes about 23,300 genes, including many previously thought to be vertebrate innovations or known only outside the deuterostomes. This echinoderm genome provides an evolutionary outgroup for the chordates and yields insights into the evolution of deuterostomes. 相似文献
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We used a before-after, control-impact design (one year pre-harvest, two years post-harvest) and unlimited-radius point counts to study the effects of typical group-selection harvesting (0.5 gaps ha−1 placed near seed trees within a standard single-tree selection harvest) and intensive group-selection harvesting (4 gaps ha−1 placed on a grid with no harvesting between gaps) on the composition and abundance of breeding birds in tolerant hardwood forests in Algonquin Provincial Park, Ontario. Percent similarity between pre- and post-harvest bird communities was 5–9% lower in selection harvested stands than in reference stands. Differences in percent similarity among the three treatments were not significant, however, suggesting that the changes in the bird community in stands harvested with group selection were not substantially different than those in reference stands. Abundance of aerial foragers and tree-and-shrub nesters increased in response to typical and intensive group selection in the second year post-harvest. By contrast, bark foragers and cavity-nesters decreased in the first year post-harvest and then increased in the second year post-harvest in response to typical group selection. Abundance of 16 (73%) of 22 species was not affected by harvesting. Blue Jay (Cyanocitta cristata), Chestnut-sided Warbler (Dendroica pensylvanica), Least Flycatcher (Empidonax minimus), and White-throated Sparrow (Zonotrichia albicollis) increased in response to intensive group selection in the first or second year post-harvest, whereas Chestnut-sided Warbler, Hairy Woodpecker (Picoides villosus), and White-throated Sparrow increased in response to typical group selection in the first or second year post-harvest. Ovenbird (Seiurus aurocapilla) decreased slightly in response to typical group selection in the second year post-harvest. Our short-term data suggest that intensive, rather than typical, group-selection harvesting is preferred for maintaining densities of cavity-nesting birds and Ovenbird; whether these advantages continue through the remainder of the cutting cycle and beyond requires further investigation. 相似文献
100.
Carmen M. H. Colitz Michael S. Renner Charles A. Manire Bethany Doescher Todd L. Schmitt Steven D. Osborn Lara Croft June Olds Erica Gehring June Mergl Allison D. Tuttle Meg Sutherland‐Smith Jens Christian Rudnick 《Veterinary ophthalmology》2010,13(Z1):47-53
Objective To characterize a form of progressive keratitis that occurs commonly in otariids. Materials and methods One hundred and thirteen captive otariids were evaluated by ophthalmologic examination and digital photography. Results Forty‐six females and 67 males were in the reference population, average age of 14 years. California sea lions predominated (n = 100); there were also six Steller sea lions, five brown fur seals, one Guadalupe fur seal and one northern fur seal. Three stages of progressive keratitis are described. Overall, 64.6% animals and 142 eyes from 113 animals (62.8%) were affected with one of three stages. The mildest form, Stage 1 keratitis, occurred in 78 of 226 eyes (34.5%); the intermediate Stage 2 keratitis occurred in 30 of 226 eyes (13.3%); and the most severe, Stage 3 keratitis, occurred in 34 of 226 eyes (15%). All but six animals had bilateral disease. Animals with Stage 1 keratitis were significantly younger than those in more advanced stages. Discussion ‘Otariid Keratitis’ occurs in all populations of eared seals evaluated. A large‐scale epidemiological study is ongoing to identify the risk factors that contribute to this disease. Exposure to chronic sunlight appears to be an important risk factor as shade diminishes clinical signs; animals kept out of sunlight the majority of the time have less severe clinical signs. Age may be important since exposure accumulates with aging. Progression of the disease is also associated with secondary opportunistic bacterial and fungal infections. The surface immune system may be imbalanced contributing to these infections and progression. 相似文献