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A survey on the present distribution of the horse chestnut leafmining moth, Cameraria ohridella Desch. & Dimic 1986, in Europe and in Italy is given: In Europe, within a period of 15 years, the leafminer – recently introduced into Central Europe – has settled in an area that spreads over 13 latitudinal and about 20 longitudinal degrees; in Northern Italy, an area of approximately 50,000 km2 has been afflicted in the 5 years since the leafminer's introduction in South Tyrol and Julian Venetia in 1993.The development of the distribution in the region of South Tyrol and Trentino is shown: In the province of Bozen-South Tyrol, between 1995 and 1999 the moth has spread in all the three principal valleys (Eisacktal, Pustertal, Etschtal); in the Trentino province, first local attacks began only in 1998, near Trento and Riva, but spread over the entire Etschtal/Adige Valley in 1999. While in South Tyrol C. ohridella was introduced from the North (North Tyrol), the introduction into the Trentino occured from the South (Verona).At present the attacks in Trentino province are preponderantly low (resulting heavy only in the city of Trento and in Riva del Garda) and limited to altitudes ranging from 70 to 700 in. In South Tyrol, attacks are mainly heavy in altitudes ranging from 250 to 900/950 m, while they are low in the increasingly affected higher altitudes of 1,000 to 1,230 m. Numeric attack parameters are given to show attack intensities.The number of generations per year depends on the respective climatic conditions: in lower-altitudes, usually three generations develop in a year, but in higher altitudes (800 to 1,100 m) only two generations; in the climatically favoured area around the Lake Garda a (partial) fourth generation appears possible.The question of host plants (Aesculus sp., Acer sp.) and the larval parasitism of C. ohridella is discussed. The parasitism of the larvae, principally by Eulophidae (Hym., Chalcidoidea), was ascertained already in the first years of attack: In South Tyrol, 16 species of parasitoids appeared, and 8 in the Trentino province, but only two species were dominant: Minotetrastichus sp. and Pnigalio sp. The level of parasitism reached was low, comparable to other Central European countries.  相似文献   
2.
A laboratory mesocosm experiment was performed to study the effects of copper-enriched sewage sludge application on a mesofauna community. For 12 weeks, characteristics and changes in this defined and artificial mesofauna community structure were monitored as well as the dynamics of leaf litter decomposition. The mesofauna community comprised six species of Collembola (Folsomia fimetaria, Isotomurus prasinus, Lepidocyrtus cyaneus, Mesaphorura macrochaeta, Parisotoma notabilis, Protaphorura armata), two species of acari Oribatida (Achipteria coleoptrata, Adoristes sp.), one species of acari Gamasida (Hypoaspis aculeifer) and one species of enchytraeid (Enchytraeus crypticus). Three treatments included the addition of 22 g dry weight (DW) sludge spiked with 0, 200 and 1,000 mg Cu kg?1 DW sludge in each mesocosm, and one treatment had 66 g DW sludge spiked with 1,000 mg Cu kg?1 DW sludge added in each mesocosm. Copper, complexed with sludge due to a favourable pH, had no effect on community and litter parameters when added to low amount of sludge. In contrast, tripling the sludge dose in addition to a high dose of Cu changed in time the sludge and leaf chemical composition as well as mesofauna community structure. Responses of the mesofauna to this treatment differed between species. The abundance of species such as I. prasinus, L. cyaneus, M. macrochaeta and P. notabilis decreased, whereas the abundance of H. aculeifer increased and became dominant.  相似文献   
3.
The fate of [14C]-amitrole herbicide was studied in eight soils having different capacities for amitrole mineralisation. Laboratory incubations were run combining different experimental conditions: temperature (4, 28 and 50°C), soil moisture (50, 100 and 150% of soil water holding capacity) and microbial activity (sterile and non-sterile conditions). During incubation, samples of the soils were periodically extracted with 0.5 M NH4OH and extracts were analysed by HPLC. The lengths of time needed for 50% dissipation of amitrole (DT50) in soils ranged from less than 1 day to more than 70 days. Amitrole mineralisation occurred only in non-sterile soils, showing that it is a biological process. Mineralisation was lower in soils with a coarse texture than in soils with a fine texture. Soil water content had little influence on the total amount of amitrole mineralised at the end of incubation. Temperature had a greater influence on mineralisation, although rates were still high at low and high temperatures. In non-sterile as in sterile soils, the major product detected in the extracts was amitrole. Additional non-identified radioactivity was occasionally extracted. However, it never represented more than 10% of initially applied amitrole. Non-extractable residues represented less than 15% of applied radioactivity in acidic soils and about 30% of applied radioactivity in alkaline and neutral soils. The amount of non-extractable radioactivity formed was enhanced in sterile as compared to non-sterile soils. Furthermore, in sterile soils, high temperature induced an increase of non-extractable residues, showing that amitrole is chemically quite reactive.  相似文献   
4.
A survey on the present distribution of the horse chestnut leafmining moth, Cameraria ohridella Desch. & Dimic 1986, in Europe and in Italy is given: In Europe, within a period of 15 years, the leafminer – recently introduced into Central Europe – has settled in an area that spreads over 13 latitudinal and about 20 longitudinal degrees; in Northern Italy, an area of approximately 50,000 km2 has been afflicted in the 5 years since the leafminer's introduction in South Tyrol and Julian Venetia in 1993.The development of the distribution in the region of South Tyrol and Trentino is shown: In the province of Bozen-South Tyrol, between 1995 and 1999 the moth has spread in all the three principal valleys (Eisacktal, Pustertal, Etschtal); in the Trentino province, first local attacks began only in 1998, near Trento and Riva, but spread over the entire Etschtal/Adige Valley in 1999. While in South Tyrol C. ohridella was introduced from the North (North Tyrol), the introduction into the Trentino occured from the South (Verona).At present the attacks in Trentino province are preponderantly low (resulting heavy only in the city of Trento and in Riva del Garda) and limited to altitudes ranging from 70 to 700 in. In South Tyrol, attacks are mainly heavy in altitudes ranging from 250 to 900/950 m, while they are low in the increasingly affected higher altitudes of 1,000 to 1,230 m. Numeric attack parameters are given to show attack intensities.The number of generations per year depends on the respective climatic conditions: in lower-altitudes, usually three generations develop in a year, but in higher altitudes (800 to 1,100 m) only two generations; in the climatically favoured area around the Lake Garda a (partial) fourth generation appears possible.The question of host plants (Aesculus sp., Acer sp.) and the larval parasitism of C. ohridella is discussed. The parasitism of the larvae, principally by Eulophidae (Hym., Chalcidoidea), was ascertained already in the first years of attack: In South Tyrol, 16 species of parasitoids appeared, and 8 in the Trentino province, but only two species were dominant: Minotetrastichus sp. and Pnigalio sp. The level of parasitism reached was low, comparable to other Central European countries.  相似文献   
5.
Water, Air, & Soil Pollution - Isotopic effects of carbonyls were investigated using the simulation reactions of carbonyls with the cysteamine derivatization. Furthermore, variations of carbon...  相似文献   
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