First report of the citrus leafhopper <Emphasis Type="Italic">Penthimiola bella</Emphasis> (Stål) (Hemiptera,Cicadellidae) in Europe

The presence of the citrus leafhopper, Penthimiola bella (Stål) (Hemiptera, Cicadellidae), was detected in citrus orchards in Portugal. This is the first report of this cicadellid in Europe. A survey was carried out in 30 citrus orchards in Algarve, in southern Portugal, based on both the beating method and visual observation of shoots, between July and December 2012. P. bella was detected in a total of 19 orchards distributed throughout the region. The occurrence of reproducing populations of P. bella and its dispersion over a relatively large area of at least 70 km in length within Algarve suggests that this species established and has been expanding its distribution in the region for several years since its arrival. The possible pathway of introduction and its pest status are discussed.     

Grassland responses to global environmental changes suppressed by elevated CO2

Simulated global changes, including warming, increased precipitation, and nitrogen deposition, alone and in concert, increased net primary production (NPP) in the third year of ecosystem-scale manipulations in a California annual grassland. Elevated carbon dioxide also increased NPP, but only as a single-factor treatment. Across all multifactor manipulations, elevated carbon dioxide suppressed root allocation, decreasing the positive effects of increased temperature, precipitation, and nitrogen deposition on NPP. The NPP responses to interacting global changes differed greatly from simple combinations of single-factor responses. These findings indicate the importance of a multifactor experimental approach to understanding ecosystem responses to global change.     

Reduced North Atlantic deep water coeval with the glacial Lake Agassiz freshwater outburst

An outstanding climate anomaly 8200 years before the present (B.P.) in the North Atlantic is commonly postulated to be the result of weakened overturning circulation triggered by a freshwater outburst. New stable isotopic and sedimentological records from a northwest Atlantic sediment core reveal that the most prominent Holocene anomaly in bottom-water chemistry and flow speed in the deep limb of the Atlantic overturning circulation begins at approximately 8.38 thousand years B.P., coeval with the catastrophic drainage of Lake Agassiz. The influence of Lower North Atlantic Deep Water was strongly reduced at our site for approximately 100 years after the outburst, confirming the ocean's sensitivity to freshwater forcing. The similarities between the timing and duration of the pronounced deep circulation changes and regional climate anomalies support a causal link.     

Pollen-style compatibility relations in natural populations of the wild diploid potato species Solanum spegazzinii Bitt.

Solanum spegazzinii Bitt., a wild diploid potato species endemic to Argentina, possesses resistance to adverse biotic and abiotic agents. Northwestern Argentinean populations grouped according to their morphological variability (G1 = localities East of the Calchaquí Valley, G2 = Calchaquí Valley and G3 = locality Belén) presented problems in seed set following controlled crosses. Thus, to evaluate if the morphological variability previously reported was sustained on a genetic basis, three introductions per group and five plants per introduction were used in controlled crosses (genotypic combinations). These were classified according to the number of seeds produced per fruit. Pollen-style compatibility relations were studied in those crosses that did not set seeds or that produced less than 30 seeds each. Within groups, G1 produced seeds normally, whereas hybridization barriers were found in 71.4% and 50.0% of the combinations within G2 and G3, respectively; on the other hand, from 46.7% to 73.3% of the combinations among groups exhibited similar barriers. Variability in the expression of the sites of pollen tube inhibition in the style was observed both within and among groups. Speculations are made on the possible hybrid origin of the populations. This revised version was published online in July 2006 with corrections to the Cover Date.     

Oued Bouhlou: A new hope for the Moroccan pearl mussel

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The 1949 Atlas of French peat deposits,a starting point for a national inventory of peatlands

Fifty per cent of European peatlands are in a damaged state. While intact peatlands are natural carbon sinks, degraded sites release important amounts of greenhouse gases into the atmosphere, contributing to global warming. Restoration of the hydrological functionality of peatlands has proved to be an efficient tool to avoid these emissions. In France, Tuffnell & Bignon's ministerial report (2019) emphasized the need for peatlands ‘integration into the National Low Carbon Strategy, targeting carbon neutrality by 2050. However, current knowledge regarding French peatlands’ distribution and carbon stocks is insufficient and does not allow decision makers and managers to prioritize areas for restoration. The most complete database to date is the 1949 Atlas, an inventory of exploitable peat deposits that was conducted during WWII for peat exploitation as fuel. Until its digitalization, the latter database was archived and never used in a scientific study. It provides detailed information about peatland surfaces, peat thicknesses and carbon contents at that time. We estimated peat carbon stocks from French peatlands to be 111 Mt C in 1949 for 63,290 ha identified as peaty sites, the equivalent of 3% of the organic carbon contained in the upper 30 centimetres of French soils. 34% of this stock was held in Lower Normandy (37.7 Mt C) and 12% in the Picardy's region (13.0 Mt C), in large lowland peatlands. However, not all peatlands were prospected in the 1949 inventory and the characteristics of the prospected peatlands may have changed with anthropic disturbances of the last decades, such as draining or climate change. These first results highlight the need for a recent inventory of French peatlands and carbon stocks based on local data aggregation. Data from the 1949 Atlas could help constituting this new inventory but should be validated before being used to describe the present.