Predicting soil loss in central and south Italy with a single USLE-MM model

Purpose

The USLE-MM estimates event normalized plot soil loss, A_e,N, by an erosivity term given by the runoff coefficient, Q_R, times the single-storm erosion index, EI₃₀, raised to an exponent b₁?>?1. This modeling scheme is based on an expected power relationship, with an exponent greater than one, between event sediment concentration, C_e, and the EI₃₀/P_e (P_e = rainfall depth) term. In this investigation, carried out at the three experimental sites of Bagnara, Masse, and Sparacia, in Italy; the soundness of the USLE-MM scheme was tested.

Materials and methods

A total of 1192 (A_e,N, Q_REI₃₀) data pairs were used to parameterize the model both locally and considering all sites simultaneously. The performances of the fitted models were established by considering all erosive events and also by distinguishing between events of different severity.

Results and discussion

The b₁ exponent varied widely among the three sites (1.05–1.44) but using a common exponent (1.18) for these sites was possible. The A_e,N prediction accuracy increased in the passage from the smallest erosion events (A_e,N?≤?1 Mg ha^?1, median error =?3.35) to the largest ones (A_e,N?>?10 Mg ha^?1, median error =?1.72). The Q_REI₃₀ term was found to be usable to predict both A_e,N and the expected maximum uncertainty of this prediction. Soil erodibility was found to be mainly controlled by the largest erosion events.

Conclusions

Development of a single USLE-MM model appears possible. Sampling other sites is advisable to develop a single USLE-MM model for a general use.

     

Downy mildew resistance evaluation in 28 grapevine hybrids promising for breeding programs in Trentino region (Italy)

Downy mildew is a major grapevine disease caused by the biotrophic oomycete, Plasmopara viticola. Numerous disease resistance studies of diverse Vitis germplasm have been previously carried out to identify downy mildew resistance sources; however, ratings were mainly reported using leaf disc in vitro testing and foliage field assessment, or upon leaf and cluster field evaluations. In the current study, 28 grapevine hybrid cultivars were screened using leaf disc bioassay, for disease resistance characterization of both existing and wild-collected materials. 16 hybrids were identified as highly resistant or resistant, and will serve as relevant resistance donors in future pre-breeding and breeding programs. All grapevine hybrids were evaluated for foliar and cluster downy mildew resistance in an untreated field trial over three successive years. This study showed that the leaf disc bioassay provided some information on the resistance level of the genotypes under scrutiny, but it was a weak predictor of their resistance level under field conditions on leaves and even more on bunches. These findings are relevant to future applications in both traditional and marker-assisted breeding programs which promote sustainable viticulture.     

Multidisciplinary study of a Lateglacial-Holocene sedimentary sequence near Bologna (Italy): insights on natural and anthropogenic impacts on the landscape dynamics

Journal of Soils and Sediments - This study investigated a Lateglacial to Holocene sedimentary sequence derived from a small catchment located at San Lazzaro di Savena in the surroundings of...     

Weak effects of habitat type on susceptibility to invasive freshwater species: an Italian case study

相似文献   

Development of an in vitro model to assess protein bioavailability in diets for common octopus (Octopus vulgaris)

An in vitro model designed to assess protein bioavailability in diets for growing Octopus was developed. The model required a previous assessment of some functional features of protein digestion in this species like the main producing organs, optimum pH for activity and total production per g tissue. The main producing organs identified were the salivary glands and the hepatopancreas (HP), being optimum pH for protease activity quite different in both organs (mostly alkaline in the posterior salivary glands and acid in the HP). In spite of the high‐specific protease activity measured in the salivary glands, a major role of the HP in protein hydrolysis is suggested due to the much bigger size of this viscera. All this information was used as a basis to develop an in vitro two‐step hydrolysis process, which simulated protein hydrolysis performed by these two organs using the Octopus enzymes. The assay was used to evaluate differences in amino acid bioavailability from several protein sources (casein, gelatin, fish meal, squid meal and krill meal) that could be used as feed ingredients for this species. As significant differences were detected both in total amount and in rate of release of the amino acids from such proteins, the model is proposed as a complementary tool in the selection and nutritional evaluation of protein ingredients to be used in diets for Octopus.     

Canine nodular dermatophytosis (kerion): 23 cases

Dermatophytosis is a common zoonotic disease, and one of its clinical presentations in the dog is nodular dermatophytosis (kerion). Because the infection is located within the dermis, routine diagnostic tests such as a Wood's lamp examination, microscopic examination of hair shafts for fungal elements and fungal culture can yield negative results. In such cases, histopathological examination with routine and special stains (periodic acid-Schiff, Gomori methenamine silver) is required to confirm the diagnosis. Nodular dermatophytosis in 23 dogs of different breed, age and sex with single or multiple nodules is described. Twelve dogs had a single nodule, and 11 dogs showed multiple lesions. Wood's lamp examination was negative in all cases. Microscopic examination of plucked hairs showed arthrospores in 8 of 23 cases. Skin scrapings in mineral oil looking for arthrospores and/or hyphae were positive in 12 cases. Impression smears of exudates were diagnostic in 21 of 23 cases (91%), showing arthrospores within fragments of hair shafts or free among neutrophils and macrophages (pyogranulomatous inflammation). Histopathology was performed in two cases. Fungal culture was positive for Microsporum canis in 16 dogs and for Microsporum gypseum in one dog. In six cases, the causative agent was not identified by fungal culture. All dogs were treated with systemic antifungal therapy and in eight cases with concurrent antibiotic therapy. Nodular dermatophytosis resolved in all dogs with the prescribed treatments within 4 to 8 weeks. Transmission to people or other pets in the home was not found.     

Gene expression study of two widely used pig intestinal epithelial cell lines: IPEC-J2 and IPI-2I

The intestinal epithelial cells (IEC) play an important role in the immune system of swine, protecting against infectious and non-infectious environmental insults. The IEC participate in the innate immune response of the intestine through different mechanisms such as barrier function, mucus secretion, antibacterial peptide synthesis and participation in the cytokine/chemokine networks.Most of the current knowledge of intestinal cell functions has come from studies conducted on cell cultures generated from human cancers or from classical animal models. However, because the molecular and cellular elements of the immune system have been selected over evolutionary time in response to the species-specific environment, models of immune function based on mouse and human need to be applied cautiously in pig. Few models of swine small intestine epithelium exist and these are poorly characterised. In the present study we characterised the basal expression of epithelial and immune-related genes of two pig small intestine cell lines, IPEC-J2 and IPI-2I, under different culture conditions. These data represent essential background information for future studies on pig-intestinal pathogen interactions.