Heterogeneity of linear forest formations: differing potential for biodiversity conservation. A case study in Italy

Trees outside forests (TOF) are important elements of the landscape and they supply goods and environmental services such as commercial production of timber and fibre, domestic production of food and firewood, carbon sequestration, conservation of habitats and species (plants and animals), erosion control and soil and water quality improvement. TOF include different types of landscape elements: small woodlands, trees along linear features such as property boundaries, roads, railways, rivers and canals, hedgerows or linear forest formations, groups of trees and isolated scattered trees, which have also different ecological functions. The article focuses on the importance and role of linear forest formations (LFF) in the rural context, with special reference to the biodiversity conservation function. It presents the results of research done in the Veneto region, north-eastern Italy. The authors have designed a sampling scheme for LFF based on the Italian National Forest Inventory and tested an indicator system in order to evaluate the quality and biodiversity of the LFF. The indicators used are: LFF type and tree species composition, vertical structure and canopy cover, naturalness, introduced species and deadwood (standing and lying). The main advantages and limitations of the applied method are discussed.     

Evidence of the concurrent circulation of H1N2, H1N1 and H3N2 influenza A viruses in densely populated pig areas in Spain

This paper reports on a serological and virological survey for swine influenza virus (SIV) in densely populated pig areas in Spain. The survey was undertaken to examine whether the H1N2 SIV subtype circulates in pigs in these areas, as in other European regions. Six hundred sow sera from 100 unvaccinated breeding herds across Northern and Eastern Spain were examined using haemagglutination inhibition (HI) tests against H1N1, H3N2 and H1N2 SIV subtypes. Additionally, 225 lung samples from pigs with respiratory problems were examined for the presence of SIV by virus isolation in embryonated chicken eggs and by a commercial membrane immunoassay. The virus isolates were further identified by HI and RT-PCR followed by partial cDNA sequencing. The HI test on sera revealed the presence of antibodies against at least one of the SIV subtypes in 83% of the herds and in 76.3% of the animals studied. Of the 600 sow sera tested, 109 (18.2%), 60 (10%) and 41 (6.8%) had SIV antibodies to subtype H1N2 alone, H3N2 alone and H1N1 alone, respectively. Twelve H3N2 viruses, 9 H1N1 viruses and 1 H1N2 virus were isolated from the lungs of pigs with respiratory problems. The analysis of a 436 nucleotide sequence of the neuraminidase gene from the H1N2 strain isolated further confirmed its identity. Demonstrably, swine influenza is still endemic in the studied swine population and a new subtype, the H1N2, may be becoming established and involved in clinical outbreaks of the disease in Spain.     

Effect of dichlorvos on cholinesterase activity of the European sea bass (Dicentrarchus labrax)

In this study, the acute toxicity of the organophosphorous pesticide (OP) dichlorvos and both in vitro and in vivo effects of dichlorvos on cholinesterase (ChE) activity of the European sea bass (Dicentrarchus labrax) were investigated. The characterisation of ChE and the “normal” range of activity in brain and muscle of non-exposed fish were determined in a first phase of the study. Acetylthiocholine was the substrate preferred of both brain and muscle ChE. Eserine sulphate and BW284C51 significantly inhibited the brain and muscle enzyme activity at low concentrations (μM range). Iso-OMPA had a significant effect in muscle, but not in brain tissue. These results suggest that acetylcholinesterase (AChE) is the predominant ChE form in brain tissue. In contrast, both acetylcholinesterase and butyrylcholinesterase seem to exist in muscle. Using acetylthiocholine as substrate, the “normal” range of fingerling head and muscle ChE were 58.05±2.11 and 118.03±8.67 U/mg protein, respectively. Corresponding values for juveniles were 43.32±4.42 and 19.44±2.44 U/mg protein for brain and muscle, respectively. Dichlorvos significantly inhibited the activity of ChE in the selected tissues, both in vitro and in vivo conditions. Differences in ChE sensitivity were found in relation to the age of the fish and the tissue analysed. The present study also showed that fingerlings of the European sea bass are relatively resistant to in vivo acute (96 h) dichlorvos exposure to concentrations between 0.125 and 1 mg/L, being able to tolerate high percentages of head ChE inhibition (37% and 76%) without lethal effects.     

Evaluation of a broad variety of coumarins,chromones, their furohomologues and thione analogues as phototoxins activated by UVA and visible light

The potential of a new kind of light-induced pesticide action was evaluated for a broad variety (32) of natural photosensitizers and their thione derivatives. The latter were synthesized to shift the absorption spectra towards the visible region and to increase the triplet and singlet oxygen quantum yields. Qualitative and quantitative evaluation of growth inhibition of Fusarium culmorum (F. G. Smith) Sacc. produced by these photosensitizers under UVA and visible light was performed on silica gel plates and in liquid medium. The results show that the phototoxicity per excited molecule of the thione derivatives using UVA light was similar to that of their parent natural compounds. On the other hand, only the thione derivatives were photoactive under visible light irradiation. These compounds show encouraging levels of phototoxicity against F. culmorum, both in liquid culture and on silica plates, and may have potential for use as photoactive pesticides.     

The potential of kales as a promising vegetable crop

Sixty varieties of kale (Brassica oleracea acephala group) from Galicia (northwestern Spain) were evaluated in two locations along with four commercial kale varieties. Data on 26 agronomic and morphological traits and five nutritional traits (crude fibre, acid detergent fibre, crude protein, calcium and potassium) were recorded. The objectives of this work were (i) to know the potential ability of kale as an horticultural crop, (ii) to assess the characteristics of local varieties of Galician kale in order to select those with the highest yield and a good adaptation to obtain improved varieties. In most traits, significant differences between locations were found, while varieties × location interaction was not significant for most of them. Significant differences were found among varieties and a high intravarietal variability was noticed in some traits. Galician kale germplasm displayed variability in the most important agronomic traits. They are characterized by their long cycles, their susceptibility to Lepidoptera pests, their good yield and adaptation to Galician conditions and their high calcium content. Four local varieties (MBG-BRS0468, MBG-BRS0476, MBG-BRS0477 and MBG-BRS0494) were the most promising for vegetal and fodder use. One of them showed the best early vigor (MBG-BRS0366) and two of them were the most resistant to Lepidoptera pest (MBG-BRS0060 and MBG-BRS0223). Kale varieties showed a high crude fibre content, and also a high acid detergent fibre, crude protein and calcium content. The varieties MBG-BRS0106, MBG-BRS0281, MBG-BRS0335 and MBG-BRS0464 could be candidates for future breeding programs since they had a good agronomic performance and a high calcium content.     

不同比例籽用西葫芦皮瓤与玉米秸秆混贮效果评价

【目的】感官评价不同比例籽用西葫芦皮瓤与玉米秸秆混贮效果,测定pH值、挥发性脂肪酸(VFA)和营养成分含量变化研究适宜添加比例。【方法】籽用西葫芦皮瓤与玉米秸秆为0∶1时作为对照组(DM 51.32),两者混合比例为1∶1、1∶2和2∶1分别作为A组(DM 40.32)、B组(DM37.56)和C组(DM 47.70)。两者按比例混合均匀后装入800 mL太空杯中,压实后密封确保无空气流通,室温避光保存。每组均设置6个处理组,60 d时取样评价青贮饲料的感官指标,测定青贮饲料pH、VFA和营养成分的变化。【结果】对照组和B组混贮尚好,A组合C组感官评价优。混贮饲料中pH值对照组极显著高于A、B和C组(P<0.01);B组极显著高于A组和C组(P<0.01)。乙酸含量对照组与B组和C组差异显著(P<0.05);A组与B组、C组差异显著(P<0.05);其他各组间差异不显著(P>0.05)。各组中均未测出丁酸含量,异丁酸含量对照组与A组和C组差异显著(P<0.05),与B组差异极显著(P<0.01)。总挥发性脂肪酸(TVFA)对照组极显著高于A组、...     

Effect of forage crop establishment on dissolved organic carbon dynamics and leaching in a hill country soil

Intensive agricultural activities could affect the dynamics and leaching of dissolved organic carbon (DOC) and nitrate from agricultural soils to receiving waters. This study investigated soil DOC dynamics immediately (0–12 days) after spraying a hill country perennial pasture with agrochemicals to establish a winter forage crop for supplementary feed production. Two treatments were examined—perennial pasture (without agrochemicals) and swede (Brassica napobrassica Mill.) cropping (after spraying with agrochemicals), both growing on a Typic Eutrudept. Soil samples were collected from various depths down to 1 m, before the application of agrochemicals (day 0) and 1, 6 and 12 days thereafter. Dissolved organic carbon concentration below the surface soil (<5 cm) was generally not altered by the agrochemicals. This was further proved by the isotopic monitoring of DOC leaching on this soil. Conversely, the agrochemicals significantly (p = 0.03) increased DOC concentration within the 0–5‐cm soil depth on day 1, due to the direct contribution of organic molecules and/or displacement of organic compounds at adsorption sites by the agrochemicals; and on day 6, due to root necromass decomposition. The increase of nitrate in soil solution at this depth (0–5 cm) on days 6 and 12 suggests that the agrochemicals may have also enhanced nitrogen (N) mineralization in the surface soil. However, the significantly (p = 0.04) higher DOC/nitrate (molar ratio) of the agrochemical treatment suggests that the agrochemicals used for clearing out pasture before forage crop establishment could lead to a short‐term increase in surface soil denitrification.     

Coarse woody debris and wood-colonizing fungi differences between a reserve stand and a managed forest in the Taborz region of Poland

The aim of this research was to evaluate the amount of woody debris (m3/ha) on the forest floor and the associated wood-colonizing fungi. The study was performed in the Taborz region, known for its Scots pine provenance experiments, against the background of a recently launched Polish legislation to protect the biodiversity on the forest floor in managed (harvested) stands. We investigated a managed stand (136-years-old) and the reserve stand ‘Sosna Taborska’(261-years-old). In the reserve stand, the mean volume of woody debris was six times higher than in the managed forests, i.e. 65 versus 11 m3/ha. In addition, in the reserve stand, the number of fungi taxa colonizing the dead wood was larger than in the managed stands, with a higher number of fruitbodies. Total fungal richness was higher in the reserve than in the managed stand, i.e. 28 versus 12 species. The dominant taxa at both sites were Fomitopsis pinicola and Fomes The aim of this research was to evaluate the amount of woody debris (m^3/ha) on the forest floor and the associated wood-colonizing fungi. The study was performed in the Taborz region, known for its Scots pine provenance experiments, against the background of a recently launched Polish legislation to protect the biodiversity on the forest floor in managed (harvested) stands. We investigated a managed stand (136-years-old) and the reserve stand ‘Sosna Taborska’(261-years-old). In the reserve stand, the mean volume of woody debris was six times higher than in the managed forests, i.e. 65 versus 11 m^3/ha. In addition, in the reserve stand, the number of fungi taxa colonizing the dead wood was larger than in the managed stands, with a higher number of fruitbodies. Total fungal richness was higher in the reserve than in the managed stand, i.e. 28 versus 12 species. The dominant taxa at both sites were Fomitopsis pinicola and Fomes fomentarius, although some taxa were only found in the reserve (e.g., Stereum hirsutum). The volume of woody debris as well as the diversity of fungi in the managed stand were lower than in the reserve, albeit greater than in other Scots pine stands in Poland. These results testify to the gains in biodiversity yielded by the management conservation management approach at the reserve stand.     

Metal mobility and mineral transformations driven by bacterial activity in acidic pit lake sediments: evidence from column experiments and sequential extraction

Journal of Soils and Sediments - Biogeochemical processes occurring in lake sediments are crucial for element cycling. In acidic pit lakes, they play a major role in acidity neutralization and...