Growing Season

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From 1950 to 1999 the majority of the world's highest quality wine-producing regions experienced growing season warming trends. Vintage quality ratings during this same time period increased significantly while year-to-year variation declined. While improved winemaking knowledge and husbandry practices contributed to the better vintages it was shown that climate had, and will likely always have, a significant role in quality variations. This study revealed that the impacts of climate change are not likely to be uniform across all varieties and regions. Currently, many European regions appear to be at or near their optimum growing season temperatures, while the relationships are less defined in the New World viticulture regions. For future climates, model output for global wine producing regions predicts an average warming of 2 • C in the next 50 yr. For regions producing highquality grapes at the margins of their climatic limits, these results suggest that future climate change will exceed a climatic threshold such that the ripening of balanced fruit required for existing varieties and wine styles will become progressively more difficult. In other regions, historical and predicted climate changes could push some regions into more optimal climatic regimes for the production of current varietals. In addition, the warmer conditions could lead to more poleward locations potentially becoming more conducive to grape growing and wine production.

This study measured the economic impacts of climate change on crop and livestock farming in Africa based on a cross-sectional survey of over 8000 farming households from 11 countries in east, west, north and southern Africa. The response of net revenue from crop and livestock agriculture across various farm types and systems in Africa to changes in climate normals (i.e. mean rainfall and temperature) is analysed. The analyses controlled for effects of key socioeconomic, technology, soil and hydrological factors influencing agricultural production. Results show that net farm revenues are in general negatively affected by warmer and drier climates. The small-scale mixed crop and livestock system predominantly typical in Africa is the most tolerant whereas specialized crop production is the most vulnerable to warming and lower rainfall. These results have important policy implications, especially for the suitability of the increasing tendency toward large-scale mono-cropping strategies for agricultural development in Africa and other parts of the developing world in light of expected climate changes. Mixed crop and livestock farming and irrigation offered better adaptation options for farmers against further warming and drying predicted under various future climate scenarios.

Resistance to fenitrothion and enzyme activities associated with the toxicity and metabolism of organophosphorus insecticides were measured in three genetically unique Daphnia magna clones collected from rice fields of Delta del Ebro (NE Spain) during the growing season and a lab sensitive clone. The studied clones showed up to sixfold differences in resistance to fenitrothion. The lack of correlation between in vitro sensitivity of acetylcholinesterase (AChE) to fenitrooxon and resistance to fenitrothion indicated that insensitivity of AChE to the most active oxon metabolite was not involved in the observed differences in resistance. Inhibition of mixed-function oxidases (MFOs) by piperonyl butoxide (PBO) increased the tolerance to fenitrothion by almost 20-fold in all clones without altering their relative ranking of resistance. Conversely, when exposed to fenitrooxon, the studied clones showed similar levels of tolerance, thus indicating that clonal differences in the conversion of fenitrothion to fenitrooxon by MFOs were involved in the observed resistance patterns. Despite that resistant clones showed over 1.5 higher activities of carboxilesterase (CbE) than sensitive ones, toxicity tests with 2-(O-cresyl)-4H-1,3,2-benzodioxaphosphorin-2 oxide, which is a specific inhibitor of these enzymes, evidenced that this system only contributed marginally to the observed clonal differences in tolerance. Glutathione-S-transferases activity (GST) varied across clones but not under exposure to fenitrothion, and was only related with tolerance levels in the field clones. In summary, our results indicate that MFO mediated differences on the bio-activation of the phosphorotionate OP pesticide to its active oxon metabolite contributed mostly in explaining the observed moderate levels of resistance, whereas the activities of CbE and GST had only a marginal role.

We analyse the factors controlling seedling establishment of Scots pine at its southernmost geographical limit (southern Spain), by monitoring emergence, survival and growth for up to 4 years in the microhabitats to which seeds are dispersed. Naturally established seedlings were monitored in two mountain ranges, and experimental sowings were performed both in woodlands and in adjacent successional shrublands into which the forest could expand. 2 Emergence was high in all microhabitats, although it was highest under the canopy of shrubs. Overall survival was low, with c. 90% of seedlings dying in the first growing season (c. 98% after several growing seasons). Survival differed among microhabitats, being highest under shrubs and extremely low (or zero) under pines or in bare soil. 3 Seedling growth was the highest in areas of bare soil, intermediate under shrubs, and very low under pines. 4 Establishment under pines was prevented by both mortality and poor performance, and good performance cannot counteract high mortality in the open. Shrubs, however, acted as nurse plants, buffering summer drought without reducing radiation to levels critical for growth, and protecting seedlings from ungulate trampling, hail and frost heave. 5 Patterns of recruitment were similar for woodland stands and successional shrublands. In addition, patterns of survival for naturally established seedlings were similar to those of seedlings originating from experimental sowings. 6 Juveniles were positively associated with shrubs but negatively with bare soil or areas below pine canopies. The facilitative effect of shrubs on seedling survival therefore changes the spatial pattern of recruitment from that determined by germination. 7 Overall, processes controlling seedling establishment in these southern Scots pine forests differ sharply from those operating in its main distribution area. The comparison among contrasting geographical ranges may contribute to an understanding of the role of environmental conditions in the balance between competition and facilitation, and assist in forecasting plant regeneration responses to global climate change.

In order to use crop simulation models to predict crop yield, unobserved daily weather, an important input for crop models, must be forecast in some sense. Due to the chaotic nature of weather and the non-linear response of crop simulation models to weather input, this forecast weather cannot simply be a single weather series (e.g. average historical weather for the upcoming growing season), but must be an ensemble of weather series, incorporating site-specific climatic variability. To capture weather uncertainty, we used the LARS-WG stochastic weather generator to produce a probabilistic ensemble of weather series by mixing observed weather from the beginning of a season with stochastically generated (synthetic) weather for the remainder of the growing season. This ensemble was used with the crop simulation model Sirius to generate distributions of crop characteristics. Progressing through the growing season, as the proportion of synthetic weather in these ensembles decreased, the distribution means converged towards the true values, allowing us to make predictions with a high level of confidence before crop maturity. In this fashion, we analysed six sites with diverse climates in Europe and New Zealand, comparing lead-times for predicting different crop characteristics at various geographic locations. We demonstrated that that there is a large difference between lead-times amongst different crop characteristics at a single location, and that there is a large variation in lead-times for predicting selected crop characteristics between locations. Variation in climates places a quantifiable limit on our ability to make crop predictions using crop simulation models.

Eddy covariance measurements of CO2 fluxes were conducted in 2004 at the agricultural site of Lonzée, Belgium, over a sugar beet crop. Additional measurements of biomass net primary production and leaf area index (LAI) were carried out. The response of the fluxes to climatic and non-climatic variables was analysed. Nighttime fluxes were dependent on turbulence, temperature and high soil water

For two growing seasons (2005 and 2006), leaves of grapevine cv. Cabernet-Sauvignon were collected at three growth stages (bunch closure, veraison, and ripeness) from 10-year-old vines grafted on 1103 Paulsen and SO4 rootstocks and subjected to three watering regimes in a commercial vineyard in central Greece. Leaf shape parameters (leaf area − LA, perimeter − Per, maximum midvein length − L, maximum width − W, and average radial − AR) were determined using an image analysis system. Leaf morphology was affected by sampling time but not by year, rootstock, or irrigation treatment. The rootstock×irrigation×sampling time interaction was significant for all the leaf shape parameters (LA, Per, L, W, and AR) and the means of the interaction were used to establish relationships between them. A highly significant linear function between L and LA could be used as a non-destructive LA prediction model for Cabernet-Sauvignon. Eleven models proposed for the non-destructive LA estimation in various grapevine cultivars were evaluated for their accuracy in predicting LA in this cultivar. For all the models, highly significant linear functions were found between calculated and measured LA. Based on r 2 and the mean square deviation (MSD), the model proposed for LA estimation in cv. Cencibel [LA = 0.587(L×W)] was the most appropriate.

feature abundance. As a result, it has been difficult to extrapolate their saturation data to other sites to make Saturation frequency and duration must be estimated to determine specific interpretations regarding saturation frequency if a site is a jurisdictional wetland, and such data also aid in assessing sites for on-site waste disposal. This study developed a method to or duration. Later work has attempted to define the estimate saturation frequency and duration by calibrating redoximor-relationship between saturation duration and occurphic features to a 40-yr record of water table simulations in a catena rence of redoximorphic features, but because these studof Atlantic Coastal Plain soils in North Carolina. Thirteen plots were ies were short-term (Ͻ3yr), the effects of saturation established along a toposequence with moderately well-drained frequency on morphology could not be addressed (Aquic Paleudults) and very poorly drained soils (Umbric Palea-(Franzmeier et al., 1983; Megonigal et al., 1993; and quults) as end members. A hydrologic model (DRAINMOD) was Jacobs et al., 2002). calibrated for each plot. Redox potential measurements showed that Some land-use regulations require that frequency and an average of 21 consecutive days of continuous saturation was suffiduration of saturated conditions be determined to assess cient for Fe reduction to occur in the soils. Historic rainfall data were a soil's suitability for a given use. For example, jurisdicused in the DRAINMOD model to estimate the number of times each plot was saturated for 21 consecutive days or longer in each tional wetlands must meet a standard for wetland hyyear of a 40-yr period. Redoximorphic features were significantly drology, which requires an area be saturated to the correlated with average number of saturation events computed to surface for at least 5% of the growing season with a have occurred at depths of 45, 60, 75, and 90 cm across all soils. frequency of at least 5 yr out of 10 (Environmental Relationships were linear and varied by depth when all soils were Laboratory, 1987). On-site wetland inspections to deteranalyzed as a single population. The r 2 values for relationships between mine whether a site meets the wetland hydrology reredox depletions and saturation events were Ͼ0.85 for saturation quirement must be completed quickly to keep up with occurring during the growing season, and were Ͼ0.75 for saturation the demand. There is currently no technology known events occurring at any time during the year. These relationships to the authors that would enable a field scientist to allow prediction of the likelihood that a soil will saturate for Ն21 d determine whether a site affected by shallow ground by simply estimating the percentage of redoximorphic features at a given depth.

Photosynthetic capacity, leaf nitrogen content, and stomatal conductance decreased with increasing leaf age in the chaparral shrub, Lepechinia calycina, growing in its natural habitat. Efficiency of resource use for three resources that potentially limit photosynthesis did not, however, decrease with increasing leaf age. Light-use efficiency, given by the quantum yield of photosynthesis at low light intensities, was unaffected by leaf aging but decreased slightly through the winter and spring growing season. Water-use efficiency, the ratio of photosynthesis to transpiration at light saturation and with a constant water vapor concentration gradient, was not affected by leaf aging or seasonal change. Nitrogen-use efficiency, the ratio of photosynthesis at light saturation to leaf nitrogen content did not change with leaf age but was lower in the leaves with the highest specific weights. This ensemble of leaf-age effects is consistent with the hypothesis that aging represents resource redistribution and not uncontrolled deterioration.

In Portugal, the wine-grape sector has a crucial economic, social and cultural relevance, especially in many inland regions of the country namely the Alto Douro Wine Region. It is the oldest legislated viticultural region in the world (since 1756) and has a typical Mediterranean climate with hot and dry summers. Recent-past temperature trends, focusing on European viticultural regions, show that the growing season mean temperatures have increased nearly 2ºC from 1950 to 2004. Future projections point to temperature increases and precipitation changes in the growing season, which may bring changes in grapevine physiology and consequently in yield and wine quality. Although grapevines have several survival strategies, the amounting evidence for significant climate change in the upcoming decades urges adaptation measures to be taken. Short term adaptation measures should be considered as the first protection strategy against climate change and should focus on specific threats. Among th...

SUMMARY - "Chemical composition and content of phenolic compounds in some woody species of North-West Tunisia". Chemical composition of 13 woody species browsed by goats in the North-West of Tunisia was studied. The ash content was low (2.6% to 6.8%). The crude protein content was less than 10% except of some species. However, the content of CP increases during growing season All studied shrubs were rich in phenolic compounds which had high inhibitory enzyme activity. It was concluded that the low level of CP and high concentration of phenolic compounds in this species could affect negatively the performance of animals conducted on this vegetation in dry season.

Soil organic matter (SOM) is known to play a major role in soil fertility due to its influence on physical, chemical and biological properties of soil; and it is closely related to particle size distribution. The ratio of SOM (g kg À1 ) to clay + silt content (g kg À1 ) was evaluated as an indicator of soil quality for barley (Hordeum vulgare) grain yield, reflecting N availability and soil physical conditions to which crop development is sensitive. Thirty-eight sites in the semiarid Pampa region of Argentina with a wide range of SOM and texture were evaluated for malting barley yield during three growing seasons. In control plots, 51% of grain yield could be explained by this indicator. The threshold value between high and low N-fertilization response was 4.4. Better yield prediction to almost 68% was achieved by combining the SOM to clay + silt indicator with initial nitrate content of the soil at seeding. This combined indicator was also able to explain a high proportion of water use efficiency, particularly in the early growth stages. The ratio of SOM to clay + silt content provided a better tool for estimating grain yield than nutrient availability or SOM alone. #

A Wetland Reservoir Subirrigation System (WRSIS) allows for capture, treatment, storage, and reuse of runoff and subsurface drainage waters from cropland, in turn providing both environmental and agricultural production benefits. The three WRSIS sites presently in operation are all located within the northwest Ohio portion of the Maumee River Basin and have been in use for five to six complete growing seasons. WRSIS components include an underground drainage pipe network tied to both a constructed wetland and a water storage reservoir. With this type of system, the drain pipes can be used at different times to either add water (subirrigation) or remove water (subsurface drainage) from the root zone, thereby enhancing crop yields, especially in dry years. Obtaining these crop yield benefits requires a proper water table management approach that includes practicing suggested operational guidelines and initiating as needed system modification improvements. By incorporating a proper water table management approach, and in comparison to control plots, WRSIS subirrigated field crop yield increases for corn and soybeans, respectively, were 34.5 and 38.1% during drier growing seasons, 14.4 and 9.7% during near average to wetter growing seasons, and 19.6 and 17.4% overall.

White-tailed deer (Odocoileus uirginianus) can cause major changes in the composition and structure of forest communities by browsing shnibs and tree seedlings and grazing understory forbs. Such effects have become an increasingly pervasive management concern in protected natural areas and parks where conservation of native plant communities is a primary objective. The magnitude of these effects can vary widely according to variations in local deer numbers and availability of alternate food sources. We used measurements from 11 maple-basswood forest fragments in southcentral Minnesota to examine the predictability of deer grazing intensity on understory forbs based on local winter deer density, composition of the landscape surroundng each forest fragment, and characteristics of forb populations within the forest. In early summer, grazing intensity on 6 palatable forb species at most sites was inversely correlated with the availability of alfalfa within a 1.5-km radius of the stand (r 2 = 0.66); winter deer density and forb flowering rate within the stand were additional important predictors of grazing intensity. Later in the growing season, most variability in the intensity of grazing among forest fragments could be explained either by the availability of row crops, alfalfa, and fields within a 1.5-km radius of the stand (r2= 0.75) or by a combination of winter deer density and forb abundance within the stand (r 2 = 0.75).Results show that parks and preserves with low densities of palatable plant species in the forest understory may be especially susceptible to effects of deer grazing. Changes in landscape composition (e.g., increased row-cropping or conversion of land to residential developments) should be an important consideration in the management of deer densities in areas designed to protect native forest communities.

A water balance study was undertaken in Niger during the 1985 growing season to quantify the root zone water balance components of three low input millet fields, to determine whether water supply was the primary limiting constraint to production and to evaluate the potential of bare fallowing as a water conservation technique. The study was conducted near the villages of Chikal, N'Dounga, and Kala Pate, which received 223, 344 and 428 mm of rainfall respectively. Seasonal crop water supply was greatest at N'Dounga, where root development was greatest. Drainage was negligible at all sites except Kala Pate, where évapo­ transpiration (ET) could not be accurately calculated after 67 days after sowing. Total ET was 272 mm at N'Dounga and 201 mm at Chikal. Based on the amount of water held in the root zone, it was concluded that water supply was the primary limiting constraint to production only at Chikal. Evaporative loss from bare soils during the month of July ranged from ...

Intensive field surveys of Convolvulus arvensis were conducted over the course of four growing seasons (1999-2002) in a 1.6 ha section of a field located in Andalusia, southern Spain, cropped with wheat in 1999 and 2001 and with sunflower in 2000 and 2002. In order to characterise the spatial and temporal variability of C. arvensis density, geostatistical techniques were used. Data from the study were used to design precise herbicide spraying. The density and spatial distribution of C. arvensis varied widely with years and crops. In general, weed density was higher in wheat years (30.41 and 53.72, in 1999 and 2001, respectively) than in sunflower ones (20.67 and 24.03, in 2000 and 2002, respectively). C. arvensis density data showed strong and moderate spatial dependence. The C. arvensis density maps achieved by kriging were used to estimate the percentage of surface susceptible to be treated with a site-specific herbicide treatment based on an estimated economic threshold (ET) for each year of study. The C. arvensis infested areas varied considerably between years and crops. About 33 and 64% of the total infested area were moderately infested (density > 14 plant m −2) in wheat in 1999 and 2001, respectively, and about 17 and 19% in sunflower years (2000 and 2002, respectively). During the years cropped with sunflower the percentage of the total area infested with C. arvensis was reduced and therefore the area exceeding the economic threshold (AEET). So, if a given herbicide were applied just only to the areas exceeding the economic threshold, the average reduction in herbicide cost achieved in sunflower years could be around 81%. These approaches demonstrated the importance of growing different crops in weed management outcome, and could be useful to farmers and researchers in formulating a multiple-season weed management plan, especially since C. arvensis has been shown to have relatively stable patches over time and crop rotations in no-tillage systems.

Grain yield and quality of winter wheat (Triticum durum L.) are affected by several factors, and crop management has a very important role among them. A 3-year (from 2003-04 to 2005-06) field experiment under irrigation was carried out at Diyabakir in the South East Anatolia Region of Turkey to evaluate immediate effects of tillage and residue management systems after cotton (Gossypium hirsutum L.) on grain yield and quality [thousand grain weight (TGW), test weight (TW), protein content (PC) and mini sedimentation (mini SDS)] of durum wheat, and correlations among these parameters. A split plot design with three replications was used, in which two residue management treatments [collecting and removing cotton stalks from plots (S Rem ), and chopping and leaving of cotton stalks in plots (S Lev )] were main plots, and six tillage and/or wheat planting method combination treatments [moldboard plough + cultivator + broadcast seeding + cultivator as conventional tillage-I (CT-I), moldboard plough + cultivator + drill as conventional tillage-II (CT-II), chisel plough + cultivator + drill as vertical tillage (VT), two passes of disk harrow + drill as reduced tillage-I (RT-I), rotary tiller + drill as reduced tillage-II (RT-II), and no-till ridge planting (RP)] were sub-plots. The effect of cotton residue management on grain yield, TW, PC, mini SDS was not significant, but S Rem (51.21 g) gave significantly higher TGW than S Lev (50.63 g). Tillage and/or wheat planting method combination treatments had a significant effect on grain yield, TGW and TW, but did not significantly influence PC and mini SDS. Conventional tillage with broadcast seeding (CT-I) treatment produced the lowest wheat grain yield (5.395 Mg ha −1 ), while there were no significant differences in grain yield among the other five tillage treatments (yields ranged from 5.671 to 5.819 Mg ha −1 ). In spite of supplemental irrigations, the variability of weather conditions, particularly the amount and distribution of rainfall during the growing season, had a significant influence on wheat grain yield and quality parameters (TGW, TW, PC, mini SDS). Grain yield had a significant positive correlation with TGW, but it did not show any relationship with other grain quality parameters. In conclusion, the findings suggest that conventional tillage with broadcast seeding would be less effective in producing grain yield of wheat compared to other five tillage treatments with row planting, while management of the previous cotton stalks may not have any effect on yield and quality of wheat except TGW.

What lessons for policy makers at national and international level can be drawn from the growing experiences of reconciling development and climate change? The key to achieving this is to approach the problem from the development perspective, since that is where in most countries the priority lies. Current knowledge on how to realize the benefits of such an integrated approach is assessed. The focus is on the main national development priorities, such as poverty reduction, disaster reduction, rural development, energy supply and transportation. Barriers and promising approaches are identified, based on the experience gained in several countries. The potential is explored for enhancing the global impact of such integrated approaches through replication of national experiences, supported by international organizations. Opportunities for large-scale initiatives are considered at national or regional level. The role of international agreements in fostering integrated development and climate policies is analysed, showing opportunities for achieving large co-benefits for addressing climate change by making use of existing policy frameworks for development and going beyond the UNFCCC framework.

Over half of the world's peat originated from Sphagnum, representing 10-15% of the terrestrial carbon stock. However, information regarding the release and exudation of organic carbon by living Sphagnum plants into the surface peat is scarce. In this study, we examined the contribution of recent Sphagnum subnitens (Russ. and Warnst.) photosynthate carbon to the peatland dissolved organic carbon (DOC) pool. This was done using a 13 CO 2 pulsechase experimental approach during the growing season. Despite the importance of Sphagnum in long-term carbon accumulation, results showed that the Sphagnum community rapidly contributes recently synthesized carbon to the peatland DOC pool. We estimate that by 4 h up to 4% of the total DOC in peat leachate was derived from 13 CO 2 pulse labelling at ambient CO 2 concentrations. Nonetheless, a huge 64% of the 13 C initially assimilated by photosynthesis was retained in Sphagnum subnitens for 23 days after labelling, consistent with the role of Sphagnum in peatland carbon accumulation. The majority of 13 C loss as respired CO 2 came within the few days post 13 CO 2 labelling, suggesting that it was derived from plant respiration of photosynthates.

Over the course of a growing season (April-October) water quality (water temperature, light, salinity, dissolved oxygen) and reproductive phenology (biomass, production of flowering shoots and seed pods, seed bank densities) were quantified in three Vallisneria americana beds in Nanjemoy Creek, MD, a tributary to the Chesapeake Bay. Clonal production of V. americana biomass increased at all sites when water temperatures rose above 25 8C. Flowering occurred during peak biomass (August-September) and resulted in the production of up to 16,000 seeds m À2 at the end of the growing season. However, observed seed bank densities represented <1% of seed production. Laboratory experiments quantified the effects of dissolved oxygen (0.29-8.00 mg l À1 ), light (0-160 mmol m 2 s À1 ), temperature (13-29 8C), salinity (0.1-17.4 psu), sediment composition (3-86% sand; 0.9-8.3% sediment organic content), and burial depth (0.2-10 cm) on V. americana seed germination. Germination of V. americana seeds was enhanced (greater overall germination and shorter time to germination) under oxygenated conditions (8.00 mg l À1 ), temperatures >22 8C, salinities of <1 psu, and in sediments composed of 3% organic content and >40% sand. Light (<160 mmol m À2 s À1 ) and burial depth (0.2-10 cm) had no significant effects on germination. Temperatures most favorable for seed germination (>22 8C) occurred in June, 2 months in the growing season just prior to development of peak vegetative standing stock. Seedlings were therefore at a distinct disadvantage to plants developed from over wintering buds. A lack of viable seed retention and inadequate environmental conditions at critical times in the growing season may be limiting seed germination success and subsequent seedling establishment within V. americana beds in the Chesapeake Bay. However, ungerminated seeds were found to maintain high viability, especially at salinities of 10 psu that can have significant negative effects of shoot growth survival. This suggests that seeds may serve as a source of reproductive material for bed recovery after periods of drought or other stressful conditions in estuarine systems. #

The Intergovernmental Panel on Climate Change (IPCC) standard methodology to conduct national inventories of soil N 2 O emissions is based on default (or Tier I) emission factors for various sources. The objective of our study was to summarize recent N 2 O flux data from agricultural legume crops to assess the emission factor associated with rhizobial nitrogen fixation. Average N 2 O emissions from legumes are 1.0 kg N ha À1 for annual crops, 1.8 kg N ha À1 for pure forage crops and 0.4 kg N ha À1 for grass legume mixes. These values are only slightly greater than background emissions from agricultural crops and are much lower that those predicted using 1996 IPCC methodology. These field flux measurements and other processlevel studies offer little support for the use of an emission factor for biological N fixation (BNF) by legume crops equal to that for fertiliser N. We conclude that much of the increase in soil N 2 O emissions in legume crops may be attributable to the N release from root exudates during the growing season and from decomposition of crop residues after harvest, rather than from BNF per se. Consequently, we propose that the biological fixation process itself be removed from the IPCC N 2 O inventory methodology, and that N 2 O emissions induced by the growth of legume crops be estimated solely as a function of crop residue decomposition using an estimate of above-and below-ground residue inputs, modified as necessary to reflect recent findings on N allocation.

Climate change is already altering the magnitude and/or frequency of extreme events which will in turn affect plant fitness more than any change in the average. Although the fingerprint of anthropogenic warming in recent phenological records is well understood, the impacts of extreme events have been largely neglected. Thus, the temperature response of European phenological records to warm and cold spells was studied using the COST725 database. We restricted our analysis to the period 1951-2004 due to better spatial coverage. Warm and cold spells were identified using monthly mean ENSEMBLES temperature data on a 0.5°grid for Europe. Their phenological impact was assessed as anomalies from maps displaying mean onsets for 1930-1939. Our results clearly exhibit continental cold spells predominating in the period 1951-1988, especially during the growing season, whereas the period from 1989 onwards was mainly characterised by warm spells in all seasons. The impacts of these warm/cold spells on the onset of phenological seasons differed strongly depending on species, phase and timing. "False" phases such as the sowing of winter cereals hardly reacted to summer warm/cold spells; only the sowing of summer cereals mirrored spring temperature warm/cold spells. The heading dates of winter cereals did not reveal any consistent results probably due to fewer warm/cold spells identified in the relevant late spring months. Apple flowering and the harvest of winter cereals were the best indicators of warm/ cold spells in early spring and summer, also being spatially coherent with the patterns of warm/cold spells.

A precision scale landscape model designed for agricultural applications is described in this paper. The Precision Agricultural Landscape Modeling System (PALMS) is a combination of two process-based models: a diffusive wave runoff model with ponding (described in detail) and a biosphere model with a crops module (briefly reviewed). Several innovations, including numerical formulations for the hydrologic properties of the soil surface with crusting, slope/tillage angle interactions, and change of roughness and detention storage with cumulative precipitation have been included. The model is compared to observations on one 1.8 ha field planted with maize and soybeans during four growing seasons, and one 24 ha field planted with maize during one growing season. Daily average soil moisture is simulated well (within 5 percent volumetric), except in extended runoff/ponding episodes. Physical processes not simulated in the model suggest possible explanations for model errors. Planned improvements for PALMS are also presented. (KEY TERMS: plant growth modeling; precision agriculture; PALMS; runoff; soil moisture; ground water recharge.)

A field study was carried out over 4 years at one site in the Low Po Valley, Northern Italy, to examine the effect of various levels of pig slurry applications on alfalfa (Medicago sativa L.) productivity, solar radiation utilization, and nutrient removal. Treatments consisted of three liquid pig manure rates, estimated to provide in total 300, 450 and 600kgNha−1year−1 (PS300,

During 2005 growing season, field experiments were conducted in two commercial raspberry fields to compare effectiveness of some fungicides and biofungicides in Botrytis cinerea control. The experiments consisted of four fungicide and two biofungicide treatments and untreated control, in randomized block design with four replicates per treatment. The fungicides: fenhxamid, vinclozolin, benomyl, and pyrimethanil were applied twice. The biofungicides Polyversum

The timing of life history traits is central to lifetime fitness and nowhere is this more evident or well studied as in the phenology of flowering in governing plant reproductive success. Recent changes in the timing of environmental events attributable to climate change, such as the date of snowmelt at high altitudes, which initiates the growing season, have had important repercussions for some common perennial herbaceous wildflower species. The phenology of flowering at the Rocky Mountain Biological Laboratory (Colorado, USA) is strongly influenced by date of snowmelt, which makes this site ideal for examining phenological responses to climate change. Flower buds of Delphinium barbeyi, Erigeron speciosus, and Helianthella quinquenervis are sensitive to frost, and the earlier beginning of the growing season in recent years has exposed them to more frequent mid-June frost kills. From 1992 to 1998, on average 36.1% of Helianthella buds were frosted, but for 1999-2006 the mean is 73.9%; in only one year since 1998 have plants escaped all frost damage. For all three of these perennial species, there is a significant relationship between the date of snowmelt and the abundance of flowering that summer. Greater snowpack results in later snowmelt, later beginning of the growing season, and less frost mortality of buds. Microhabitat differences in snow accumulation, snowmelt patterns, and cold air drainage during frost events can be significant; an elevation difference of only 12 m between two plots resulted in a temperature difference of almost 28C in 2006 and a difference of 37% in frost damage to buds. The loss of flowers and therefore seeds can reduce recruitment in these plant populations, and affect pollinators, herbivores, and seed predators that previously relied on them. Other plant species in this environment are similarly susceptible to frost damage so the negative effects for recruitment and for consumers dependent on flowers and seeds could be widespread. These findings point out the paradox of increased frost damage in the face of global warming, provide important insights into the adaptive significance of phenology, and have general implications for flowering plants throughout the region and anywhere climate change is having similar impacts.

2006. Using a proxy of plant productivity (NDVI) to find key periods for animal performance: the case of roe deer. Á/ Oikos 112: 565 Á/572. Animals in seasonal environments are affected by climate in very different ways depending on season and part of the climatic effects operates indirectly through the plants. Vegetation conditions in spring and summer are regarded as decisive for the reproductive success and the offspring's condition of large herbivores, but objective ways to determine key periods during the growing season have not been done often due to limitations in plant data. Using satellite data (NDVI), we determined how plant productivity from birth to fall influences the following winter body mass of roe deer fawns. We do this in two populations, the first inhabiting the low productive Chizé reserve in south western France with an oceanic climate and the second from Trois Fontaines, a highly productive forest with continental climate in east France. The effect of plant productivity was similar for male and female fawn mass, as expected from the weak intensity of sexual selection in roe deer life history traits. We found contrasting results between sites, with a strong effect of plant productivity in spring (April-May) in the Chizé population, but no effect in the Trois Fontaines population. The relatively low variability in winter fawn body mass could account for the absence of NDVI effects at Trois Fontaines. However, such results might also point to a limitation in the use of the NDVI, since the relationship between the canopy and the plant productivity at the ground level might be weak in the highly productive forest of Trois Fontaines.

Transpiration rates were measured in a flooded population of Phragmites australis ssp. altissima in a wetland located in El Hondo Natural Park (southeastern Spain) during the growing season of 2000. The heat balance method for measuring sap flow was used to calculate the rate of water transpiration on a whole-stem basis. Four series of measurements were carried out in selected weeks in May, June, August and October. Structure, biomass and leaf area index of the reed population were simultaneously quantified in order to scale transpiration on a plot-area basis.Overall, transpiration flux was high during the sampling period and showed a typical diurnal pattern with a maximum at about midday. Mean transpiration was highest at the end of June coinciding with the peak of reed growth and with the maximum leaf area both at individual and plot scales. Rates decreased abruptly in October, in parallel with the advanced foliar senescence. The variation of both midday and integrated daily transpiration is significantly related to that of the air temperature on clear days. Cloudy and rainy days exert a pronounced effect on water loss by decreasing transpiration. Our results highlight the potential use of the sap-flow method to measure transpiration in reed ecosystems and the relevance of this flux for the water balance in wetlands in semi-arid environments. Thus, it is suggested that water management in these areas could be favoured by acquiring high-quality experimental data.

Simulation of crop yield allows better planning and efficient management under different environmental inputs such as water and nitrogen application. However, most of the models are complicated and difficult to understand. Furthermore, input data are not readily available. The objectives of this investigation were to use logistic equation to quantify the influence of seasonal water and nitrogen application on maize biomass accumulation and grain yield and to develop empirical models for prediction of maize biomass and grain yield. Logistic equations were fitted to dray matter (DM) yield at different times in the growing season at different irrigation water and nitrogen levels. The parameters of the logistic equations were then fitted to irrigation water and nitrogen as empirical functions. Further, the harvest index (HI) was related to the applied water and nitrogen as another empirical model. The empirical logistic models were used to estimate the DM and grain yield based on data from another experiment in the same area. Results indicated that the empirical models predicted the DM yield during the growing season with an acceptable accuracy, but dry matter (DM) prediction at harvest was very good. The grain yield also was predicted with a very good accuracy. It is concluded that logistic equation along with the presented empirical models for prediction of constants in logistic equation and HI are appropriate for accurate prediction of DM and grain yield of maize at the study region.

Eddy covariance measurements of CO 2 fluxes were conducted in 2004 at the agricultural site of Lonzée, Belgium, over a sugar beet crop. Additional measurements of biomass net primary production and leaf area index (LAI) were carried out. The response of the fluxes to climatic and non-climatic variables was analysed. Nighttime fluxes were dependent on turbulence, temperature and high soil water content. The u * correction was determined using a statistically based algorithm. The lower u * threshold was 0.1 m s À1 . Daytime fluxes during maximum canopy development depended mainly on incident radiation and its repartition between direct and diffuse components. A limited response to saturation deficit and soil water content was also observed. The evolution of assimilation and respiration throughout the growing season was studied. Maximum assimilation fluxes were observed in July when canopy had not fully developed and these then decreased from the end of July to the harvest, due not only to a reduction in radiation but also to a reduction in canopy assimilation capacity. Normalised respiration evolution presented two peaks during the year: the first in July, when the assimilation was at its greatest, and the second after the harvest, during the crop residues decomposition. The annual sequestration, estimated by half-hourly flux summing and measurement gap filling, was À0.61 AE 0.11 kg C m À2 and the impact of the u * correction and of the residues decomposition was estimated to be 5.3 and 3.5%, respectively.