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Distribution of Japanese beetle, Popillia japonica Newman, grubs and dispersal of an entomopathogenic nematode, Heterorhabditis bacteriophora Poinar ‘Oswego' strain (an isolate from New York state), were examined for 5 wk within soil-filled flats containing grass. Japanese beetle grubs uniformly dispersed to all sections of the flats not infested with H. bacteriophora ‘Oswego' strain. In flats infested with H. bacteriophora ‘Oswego' strain, however, greater proportions of Japanese beetle grubs were recovered in sections near the nematode release site or center sections of the flats. H. bacteriophora ‘Oswego' strain dispersed to all sections of the flats but dispersed more rapidly within the flats infested with Japanese beetle grubs than in flats not infested with Japanese beetle grubs

A control decision rule for European chafer, Rhizotrogus (Amphimallon) majalis (Razoumowsky), larvae infesting turfgrass was developed using data from 317 residential sites. Larvae were often abundant enough to cause damage to turf in portions (patches) of properties when average density over an entire site was much less than a damage threshold of 5-10 grubs per 950 cm2. To account for this, an empirical relationship between the size of the largest patch of European chafer larvae at a site and site-wide density was used in the development of the decision rule. Properties with a patch of grubs in excess of ≍30 m2 were deemed to require insecticide treatment. Site characteristics (lawn age, shade, and percentage of Kentucky bluegrass) were related to site-wide density and this relationship was used to formulate a risk assessment system. This system is used to determine whether a site should be sampled or not. Properties that are not sampled are not to be treated. Other treatment decisions are based on the outcome of sampling. The relationship between site-wide density and patch size did not allow clear identification of a density that could be used as a threshold in a sampling program. Therefore, several sampling plans were constructed that classified density according to different threshold values. Operating characteristic functions were used in combination with the aforementioned relationship between density and patch size to calculate two types of errors for each sampling plan: the probability of not treating when treatment was necessary and the probability of treating when treatment was not required. Based on these error functions, a threshold of 0.25 grubs per ll-cm diameter turf plug was advocated. Use of the proposed control decision rule should result in few treatment errors but could lead to considerable reductions in pesticide use

Movement patterns of japanese beetle, Popillia japonica Newman, and European chafer, Rhizotrogus (Amphimallon) majalis (Razoumowsky), grubs as influenced by gravity, host plant position, and external disturbances were studied in laboratory soil-turfgrass microcosms. Second through third instars just before pupation were monitored using radiographic techniques. Neonates were monitored using destructive sampling. Results demonstrate significantly different movement patterns between species and among age groups. The development stage of the grub had a large effect on Japanese beetle grub behavior and a measurable, but lesser effect, on European chafers. All larval stages of European chafers and all larval stages of Japanese beetle, except neonates and postoverwintering third instars, displayed a downward movement in response to disturbance. Neonate Japanese beetles showed little movement while postoverwintering. Japanese beetles moved upward when disturbed. European chafer grubs of all age classes displayed random vertical movement with some arrestment in or near sod. Preoverwintering and postoverwintering third-instar chafers showed less dramatic arrestment behavior than other instars tested. Second-instar Japanese beetles behaved similarly to European chafers; however, third instars behaved very differently. All third instars except those tested in late winter and early spring showed some innate downward movement in the soil microcosms. Japanese beetles tested in late winter displayed random movement with some arrestment in sod, whereas those tested in early spring exhibited upward movement and arrestment in sod

Inverse modeling is widely employed to provide "top-down" emission estimates using atmospheric measurements. Here, we analyze the dependence of derived CH4 emissions on the sampling frequency and density of the observational surface network, using the TM5-4DVAR inverse modeling system and synthetic observations. This sensitivity study focuses on Europe. The synthetic observations are created by TM5 forward model simulations. The inversions of these synthetic observations are performed using virtually no knowledge on the a priori spatial and temporal distribution of emissions, i.e. the emissions are derived mainly from the atmospheric signal detected by the measurement network. Using the European network of stations for which continuous or weekly flask measurements are available for 2001, the synthetic experiments can retrieve the "true" annual total emissions for single countries such as France within 20%, and for all North West European countries together within ~5%. However, larger deviations are obtained for South and East European countries due to the scarcity of stations in the measurement network. Upgrading flask sites to stations with continuous measurements leads to an improvement for central Europe in emission estimates. For realistic emission estimates over the whole European domain, however, a major extension of the number of stations in the existing network is required. We demonstrate the potential of an extended network of a total of ~60 European stations to provide realistic emission estimates over the whole European domain.

Methane retrievals from the Scanning Imaging Absorption Spectrometer for Atmospheric Chartography (SCIAMACHY) instrument onboard ENVISAT provide important information on atmospheric CH4 sources, particularly in tropical regions which are poorly monitored by in situ surface observations. Recently, Frankenberg et al. (2008a, 2008b) reported a major revision of SCIAMACHY retrievals due to an update of spectroscopic parameters of water vapor and CH4. Here, we analyze the impact of this revision on global and regional CH4 emissions estimates in 2004, using the TM5-4DVAR inverse modeling system. Inversions based on the revised SCIAMACHY retrievals yield ~20% lower tropical emissions compared to the previous retrievals. The new retrievals improve significantly the consistency between observed and assimilated column average mixing ratios and the agreement with independent validation data. Furthermore, the considerable latitudinal and seasonal bias correction of the previous SCIAMACHY retrievals, derived in the TM5-4DVAR system by simultaneously assimilating high-accuracy surface measurements, is reduced by a factor of ~3. The inversions result in significant changes in the spatial patterns of emissions and their seasonality compared to the bottom-up inventories. Sensitivity tests were done to analyze the robustness of retrieved emissions, revealing some dependence on the applied a priori emission inventories and OH fields. Furthermore, we performed a detailed validation of simulated CH4 mixing ratios using NOAA ship and aircraft profile samples, as well as stratospheric balloon samples, showing overall good agreement. We use the new SCIAMACHY retrievals for a regional analysis of CH4 emissions from South America, Africa, and Asia, exploiting the zooming capability of the TM5 model. This allows a more detailed analysis of spatial emission patterns and better comparison with aircraft profiles and independent regional emission estimates available for South America. Large CH4 emissions are attributed to various wetland regions in tropical South America and Africa, seasonally varying and opposite in phase with CH4 emissions from biomass burning. India, China and South East Asia are characterized by pronounced emissions from rice paddies peaking in the third quarter of the year, in addition to further anthropogenic emissions throughout the year

The key objective of the project "Use of the MSG SEVIRI channels in a combined SSM/I, TRMM and geostationary IR method for rapid updates of rainfall" is the development of algorithms for rapid-update of satellite rainfall estimations at the geostationary (GEO) scale. The new channels available with the Spinning Enhanced Visible and Infrared Imager (SEVIRI) radiometer in the visible (VIS), near infrared (NIR) and infrared (IR) portions of the spectrum provide new insights into the microphysical and dynamic structure of precipitating clouds thus allowing for a more precise identification of precipitation intensities. Passive microwave (PMW) radiometers on board low Earth orbiting (LEO) satellites are used to determine information on the vertical cloud structure. Key features of the new method(s) are: 1. Microphysical characterization of precipitating clouds with VIS/IR sensors; 2. Creation of cloud microphysical and radiative databases from cloud model outputs and aircraft penetrations; 3. Tuning of PMW algorithms for different cloud systems (maritime, continental, convective, stratiform,...); 4. Combination of data from different algorithms and application to a rapid updatecycle at the GEO scale. The project provided the background for EURAINSAT "European Satellite Rainfall Estimation and Monitoring at the Geostationary Scale", a research project co-funded by the Energy, Environment and Sustainable Development Programme of the European Commission within the topic "Development of generic Earth observation technologies". The project web site is accessible at http://www.isac.cnr.it/~eurainsat/. Moreover, it has represented the European framework for the launch of the International Precipitation Working Group (IPWG). A brief account of the major research and organizational results will be given in the following.