SSS9.5

Three slopes with grapevines were investigated to see changes in the soil-plant-water system over vegetation growth. The slopes have the following parameters: 1) young grapevine plants with tilled soil (YR), 2) older grapevines with grassland between rows next to the young grapevine (OR), and 3) older grapevines with grass between rows at a different location and slope position (OF). All experimental slopes had identical plant canopy management such as pruning or shoot and bunch thinning. All slopes are prone to erosion. For continuous hydrological monitoring soil water content and temperature sensors were placed at 15 cm and 40 cm below ground both at the top and bottom of the slopes. For indications of plant growth photosynthetically active radiation (PAR) sensors were placed below the canopy, and Normalized Difference Vegetation Index (NDVI) and Photochemical Reflectance Index (PRI) sensors were used to monitor leaf reflectance. All sites included a set of hemispherical sensor sets to measure incoming radiation. Leaf Area Index (LAI) was measured on a biweekly basis using a handheld ceptometer. We found that in the OR and OF sites the soil water content (VWC) was higher at the lower portion of the slope, while for the YR the VWC was the highest at the top. Soil temperature was higher at the top of the slopes over 6% for YR and 9% for OR sites compared to the bottom measuring points. The most notable difference in the NDVI values was observed for OR, where the plants at the top of the slope showed much lower NDVI values compared to the ones at the bottom of the slope. For the younger grapevines, this tendency was showing the opposite results, the plants at the top of the slope had much higher NDVI values than the lower ones, indicating higher leaf densities. The collected PAR values further support these findings, as the OR plants at the top of the slope had the highest PAR values signifying lower leaf areas and densities. The differences in the PRI values suggest that plants at the bottom of the slope have either better nutrient usage or less stress for drought conditions. The LAI values correlated well with the spectral reflectance sensor data. The OR and OF showed higher LAI at the bottom of the slope, while the younger grapevines showed the opposite. The highest LAI values were observed for the YR (max values were around 7) and the lowest for the OF plants (max LAI value was 3.2).

How to cite: Horel, A., Zagyva, I., Dencső, M., Tóth, E., Gelybó, G., and Bakacsi, Z.: Spatial variability of soil water content and soil chemistry affect grapevine growth in degraded slopes, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-4403, https://doi.org/10.5194/egusphere-egu21-4403, 2021.

Weather conditions in a given year largely control wine production, despite all the mitigation measures that can be undertaken in the vineyards and wineries. As such, seasonal weather forecasts can be a valuable decision support tool for assisting winemakers in short to medium-term management, particularly when coupled with wine production models. Adequate and timely agricultural management grounded on predicted wine production will reduce the risks and enhance the efficiency of the sector. In this study, the performance of seasonal weather forecasts of wine production in the Portuguese Douro & Port wine region (D&P WR) is evaluated. However, this concept can be extended to other wine regions worldwide. A predictive logistic model of wine production is developed herein. Monthly mean air temperatures and monthly total precipitation, averaged over the periods of February–March, May–June, and July–September, and an autoregressive component of wine production are taken into account for this purpose. The wine production time series for the D&P WR and over the period 1950–2017 (68 years) is categorized into three classes based on quantiles: high, normal and low production years. The empirical wine production model reveals a correct estimation ratio of nearly 2/3 when applied to independent 10%-random subsamples taken from the complete time series. The performance of the ECMWF 7-month seasonal weather forecasts (issued from February to August) to predict the temperature and precipitation variables used in the wine production model is subsequently assessed. The results show a reasonable performance in predicting these variables. Furthermore, the forecasts from May to August are clearly the best performing, as 1) more observed data is included in the empirical wine production model, and 2) the performance of seasonal forecasts for summer months is higher, owing to the local Mediterranean-type climate characteristics, with typically dry and settled atmospheric conditions in summer. The extension of this approach to other wine regions in Europe, as well as its operational application, are foreseen in the near future within the framework of the European Commission-funded action “Climate change impact mitigation for European viticulture: knowledge transfer for an integrated approach – Clim4Vitis” [grant number 810176].

How to cite: Santos, J. A., Ceglar, A., Toreti, A., and Prodhomme, C.: Seasonal weather forecasts as a decision support tool in the Douro Wine Region, Portugal, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-683, https://doi.org/10.5194/egusphere-egu21-683, 2021.

The Mediterranean wine regions are characterized by a marked intra (and inter) annual climate variability, where high water deficits in the atmosphere and soil can develop, particularly during the summer. In addition, the climate change scenarios point to an intensification of these environmental conditions in the near future. Thus, the combination of survival strategies, which include the ability to reduce water losses, increase absorption or control dehydration, becomes an important tool for crop water management. Adaptation measures involving cultural practices must also be adopted to ensure the sustainability of the wine sector. One of the main adaptation viticultural practice is the selection of the training system. In this context, mature vines trained to two different systems in the Douro Demarcated Region (NE Portugal) were selected and several measurements (e.g. weather variables, soil moisture, leaf water potential, leaf area index, sap flow and trunk diameter fluctuations) were performed under variable soil water availability. The results highlight the key role of plant survival strategies, such as stomatal control and adjustment of the total leaf area, in order to reduce transpiration, as well as a nocturnal rehydration. Furthermore, and in terms of water dynamics, the results point to the effect of the shorter length of the hydraulic pathways of the Guyot-trained vines, in contrast to the higher trunk and the permanent horizontal cordon of the vines trained to spur pruned cordon. The research findings support the selection of the Guyot as a training system that is better adapted to the projected climate change in Mediterranean wine-producing regions.

How to cite: Malheiro, A. C., Dinis, L.-T., Conceição, N., and Moutinho-Pereira, J.: Grapevine survival strategies and training system as an adaptation measure under Mediterranean climate, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-1814, https://doi.org/10.5194/egusphere-egu21-1814, 2021.

Proximal sensing is being integrated into vineyard management as it provides rapid assessments of spatial variability of soils’ and plants’ features. The electromagnetic induction (EMI) technology is used to measure soil apparent electrical conductivity (EC_a) with proximal sensing and enables to appraise soil characteristics and their possible effects on plant physiological responses. This study was conducted in a micro irrigated Cabernet Sauvignon (Vitis vinifera L.) vineyard to investigate the technical feasibility of appraising plant water status and its spatial variability using soil EC_a and must carbon isotope ratio analysis (δ¹³C). Soil temperature and soil water content were monitored in-situ using time domain reflectometry (TDR) sensors. Soil EC_a was measured with EMI at two depths [0 – 1.5 m (deep EC_a) and 0 – 0.75 m (shallow EC_a)] over the course of the crop season to capture the temporal dynamics and changes. At the study site, the main physical and chemical soil characteristics, i.e. soil texture, gravel, pore water electrical conductivity (EC_e), organic carbon, and soil water content at field capacity, were determined from samples collected auguring the soil at equidistant points that were identified using a regular grid. Midday stem water potential (Ψ_stem) and leaf gas exchange, including stomatal conductance (g_s), net carbon assimilation (A_n), and intrinsic water use efficiency (WUE_i) were measured periodically in the vineyard. The δ¹³C of produced musts was measured at harvest. The results indicated that soil water content (relative importance = 24 %) and texture (silt: relative importance = 22.4 % and clay: relative importance = 18.2 %) were contributing the most towards soil EC_a. Deep soil EC_a was directly related to Ψ_stem (r² = 0.7214) and g_s (r² = 0.5007). Likewise, δ¹³C of must was directly related to Ψ_stem (r² = 0.9127), g_s (r² = 0.6985), and A_n (r² = 0.5693). Results from this work provided relevant information on the possibility of using spatial soil EC_a sensing and δ¹³C analysis to infer plant water status and leaf gas exchange in micro irrigated vineyards.

How to cite: Kurtural, S., Yu, R., and Zaccaria, D.: Soil apparent electrical conductivity and must carbon isotope ratio provide indication of plant water status in wine grape vineyards, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-8472, https://doi.org/10.5194/egusphere-egu21-8472, 2021.

In the Mediterranean region, climate-change-driven increasing temperature and frequency of prolonged drought periods are affecting physiological behaviour and vine growth, with consequences on berry yield and quality. Assessing how plants have reacted to past environmental fluctuations can help understanding current plant behaviour and forecast possible responses to climate changes. The improvement of knowledge about the plasticity of morpho-functional traits in vines as response to climatic stress conditions can help the management of vineyards.

In this study, we applied a wood-sciences approach to reconstruct past vine hydraulic behaviour in four vineyards of Vitis vinifera L. subsp. vinifera ‘Falanghina’ located in southern Italy (La Guardiense farm, Benevento, Campania region), cultivated in different pedo-climatic conditions onto the same rootstock. Wood cores were extracted by the vine trunk and prepared for microscopy and stable isotope analyses to quantify functional wood anatomical traits and δ¹³C to assess plant water use efficiency.

Vineyard performances were also monitored in vivo at the main phenological phases (flowering, fruit set, veraison, ripening), through the analysis of morphological, eco-physiological and production parameters. Stable isotopes were also traced in leaves and must. Soil profiles were characterised at the four sites that were also monitored for main climatic factors.

All parameters linked with vine hydraulics, resource use and growth efficiency showed a site-specific precise coordination linked with different water and resource availability as influenced by pedo-climatic conditions. The different vines hydraulic behaviour at the four sites, derived from the analysis of the tree-ring series and confirmed by in vivo plant monitoring, contributed to different vines productivity and quality of musts. The isotopic signal of wood and must showed a similar trend, suggesting that they both record the same ecophysiological information. These innovative results suggest the possibility to use must as a good matrix to perform carbon isotope analysis and derive information on plant water use in response to pedo-climatic factors.

The overall information gained through the proposed methodological approach seem to be promising to better understand plant-environment relations in the continuum soil/plant/atmosphere, useful for the management of vineyard to achieve a more sustainable wine production.

How to cite: Damiano, N., Battipaglia, G., Cirillo, C., Erbaggio, A., Cherubini, P., Bonfante, A., and De Micco, V.: Reconstruction of vine hydraulic behaviour from tree-ring series up to must in Falanghina under different pedo-climatic conditions, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-8790, https://doi.org/10.5194/egusphere-egu21-8790, 2021.

Ongoing changes in climate (both in the means and the extremes) are increasingly challenging grapevine production in the province of South Tyrol (Italy). Here we ask the question whether sun-induced chlorophyll fluorescence (SIF) observed remotely from space can detect early warning signs of stress in grapevine and thus help guide mitigation measures.

Chlorophyll fluorescence refers to light absorbed by chlorophyll molecules that is re-emitted in the red to far-red wavelength region. Previous research at leaf and canopy scale indicated that SIF correlates with the plant photosynthetic uptake of carbon dioxide as it competes for the same energy pool.

To address this question, we use time series of two down-scaled SIF products (GOME-2 and OCO-2, 2007/14-2018) as well as the original OCO-2 data (2014-2019). As a benchmark, we use several vegetation indices related to canopy greenness, as well as a novel near-infrared radiation-based vegetation index (2000-2019). Meteorological data fields are used to explore possible weather-related causes for observed deviations in remote sensing data. Regional DOC grapevine census data (2000-2019) are used as a reference for the analyses.

How to cite: Wohlfahrt, G., Hammerle, A., Raifer, B., and Haas, F.: Early stress detection in grapevine – can remotely-sensed sun-induced chlorophyll fluorescence do the job?, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-5171, https://doi.org/10.5194/egusphere-egu21-5171, 2021.

Climate change is one of the main challenges for future agriculture since it can severely affect plant growth and development. The Mediterranean area is one of the most vulnerable regions where climatic models have forecasted a significant increase in frequency and severity of drought events. Ongoing climate change is aggravating some critical issues in the production of the autochthonous grape variety Greco, widely cultivated in the Campania Region (southern Italy) and used alone or blend in many quality label wines.

Nowadays, there is a high risk for the economic sustainability of Greco cultivation due to the following main issues: reduced vine productivity, low selling price of grapes, and territory fragmentation. Such criticisms induce the abandonment of small/medium-sized farms due to either crop conversion or consolidation into larger farms.

The Greco variety may represent a study model to introduce innovative and integrated management of cultivation techniques, such as pruning and soil management, with the aim to resolve similar problems affecting other autochthonous regional cultivars. They include issues, such as low fertility, that cause an unbalanced ratio among sugars, acids, and affect grape metabolites important for the oxidative stability and sensory quality of wine.

The GREASE project, funded by Campania Region within the Rural Development Programme 2014-2020, falls within the framework of sustainable management of vineyards (from economic, environmental and social viewpoints) with an insight to climate change. The general objective to improve the potential production of Greco concerns the management of major cultivation practices in viticulture by the realization of a cultivar-specific model for vine canopy and soil management. Optimization of parameters is important in order to achieve a good vegetative and reproductive balance that enhances grape and wine quality, improves farm profitability and environmental sustainability. This project is conducted in a vineyard of Vitis vinifera L. subsp. vinifera ‘Greco’ located in southern Italy (Feudi di San Gregorio farm).

The projects has 3 main inter-disciplinary actions: A1) to determine the effect of diverse vine pruning systems on plant resource use, through the reconstruction of vine eco-physiological history (dendro-anatomical and -isotopic analyses); A2-A3) to analyse the effect of soil management and of vine training systems on the continuum soil-plant-atmosphere system. Specific activities include: pedoclimatic, vegetative and reproductive, physiological and hydraulic characterization; microvinification and characterization of grapes and wine produced in the different trials; evaluation of resources use efficiency, pests, footprint family markers; model development.

The impact of the project on other wineries of the Campania Region will be significant due to an increased understanding of how cultivation systems influence the efficient use of available resources in the Greco vineyard. Such knowledge would be useful to design simple modifications to the presently used agronomical practices, to achieve production and economic gains without long-term structural investments. This know-how will also favour other downstream technologies and biotechnologies of viticulture and enology production, as well as the associated companies (e.g., producers of fertilizers, seeds for green manure) to realize products and services better adapted to the development of cultivar-specific viticultural and enological production systems.

How to cite: Cirillo, C., Bonfante, A., Battipaglia, G., Gambuti, A., Woo, S. L., Arena, C., Castaldi, S., Erbaggio, A., Pagano, L., and De Micco, V.: The GREASE project: Sustainable cultivation of Greco grapevine - Resource use efficiency and application of the footprint family indicators, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-9807, https://doi.org/10.5194/egusphere-egu21-9807, 2021.

The increasing irregularity in precipitation patterns and frequency of extreme drought events in the Mediterranean area is challenging the sustainability of grapevine production, especially in some areas of southern Italy. Here, being the grapevine mostly rainfed-cultivated, there is a strong demand for cultivation techniques aiming to improve water use efficiency and water stress tolerance.

Pruning techniques and training system can have an effect on the hydraulic architecture of vines, thus on their hydraulic behavior that is strictly coordinated with photosynthetic efficiency and ultimately contribute to determine yield and grape quality.

In this study, we aimed to evaluate whether and to what extent a change in pruning technique can influence the efficiency and safety of water flow in vines. In order to pursue this objective, we combined the dendro-sciences approach, analysing tree-ring width and anatomical features of vines subjected to an abrupt change in the pruning technique. The study was conducted within the GREASE project, funded by the Campania Region through the Rural Development Programme 2014-2020, within the framework of the optimization of agricultural practices for improving grapevine resources-use efficiency for the sustainable management of vineyards.

The study was conducted in a vineyard of Vitis vinifera L. subsp. vinifera ‘Greco’ (Feudi di San Gregorio farm) located in southern Italy (Avellino) at a site where the pruning technique was changed in 2004 following the method by Simonit & Sirch (Simonit 2014 Manuale di potatura della vite Ed IA; Sun et al 2008 Am J Bot 95:1498-1505). This method applies pruning cuts oriented in a way to drive vine natural tendency in the branching, to reduce injuries stress, in order to modulate the hydraulic pathway to reduce resistances to flow. Wood cores were extracted by the vines trunk, tree-rings were dated and widths were measured according to dendro-chronological techniques using WinDENDRO software. Then the cores were subjected to thin sectioning to obtain tree-ring series that were analysed through microscopy and subjected to digital image analysis. Wood anatomical traits, linked with hydraulic conductivity and vulnerability, were quantified in each year. The tree-ring series were then annually separated and d¹³C was measured in each year, in order to obtain information on intrinsic water use efficiency. The overall wood anatomical and stable isotope parameters were integrated to reconstruct and interpret past eco-physiological vine behaviour in response to the change in pruning technique also taking into account the inter-annual environmental variability.

The analysis of wood anatomical functional traits linked with carbon stable isotopes of grapevine tree-ring series confirmed that vineyard management technique can severely affect the vine water use, thus affecting plant growth, productivity and ultimately plant ability to adapt to changing environmental conditions.

All these interactions and their effects on water use should be taken into account when designing management practices in vineyards for sustainable production.

How to cite: De Micco, V., D'Auria, A., Niccoli, F., Petracca, F., De Francesco, S., Altieri, S., Pacheco Solana, A., Erbaggio, A., Sirch, P., Cirillo, C., and Battipaglia, G.: The GREASE project: Sustainable cultivation of Greco grapevine - Reconstruction of the vines ecophysiological behaviour, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-10106, https://doi.org/10.5194/egusphere-egu21-10106, 2021.

The concept of “Vineyard Geological Identity” (VGI) was introduced (Ferretti, 2019: Catena) in recognition of the role of geologic setting in contributing to fertility, hydrology, and other important aspects of vineyard soils.  This study applied the VGI concept to two vineyards in the Champlain Valley of Vermont, USA where a burgeoning wine-making industry has been catalyzed by the development of French-American hybrid grape variety capable of surviving cold winters and bringing fruit to ripeness in relatively cool summers.  The vineyards studied here, “LP” and “SV”, both produce the hybrid grape known as “Marquette”, are at a similar elevation (~100 m), have a similar macroclimate (MAT ~7 °C, MAP ~ 850 mm, ~1400 GDD), and were inundated by proglacial Lake Vermont during deglaciation (~15,000 years ago).  Notable differences between the sites are the lithology of the underlying bedrock (Ordovician carbonate at LP, and Cambrian quartzite at SV), and the fact that the SV site was located at the edge of a marine embayment at the Pleistocene/Holocene transition after Lake Vermont drained.  The hypothesis tested was the prediction that despite their broadly similar physical settings and geologic histories, the VGI of the two vineyards would vary as a result of differences in their underlying bedrock and the soil parent materials at these settings.  Samples were collected at depths of 25, 50, 75, and 100 cm from 10 locations within the Marquette block at in each vineyard.  All samples were evaluated for grain size distribution (with the hydrometer method and a laser scattering analyzer), thermogravimetric analysis (from 25 to 1000 °C), pH, nutrient status, base saturation, and cation exchange capacity.  The deepest samples were also analyzed for mineralogy (with XRD) and major element chemistry (with XRF).  Results confirm the tested hypothesis.  Most base cations are significantly more abundant in the samples from the LP site (reflecting the underlying carbonate bedrock), and the LP site is significantly finer grained (reflecting its former deepwater location in Lake Vermont).  Conversely, at the SV vineyard Na is significantly more abundant and samples are significantly coarser, consistent with the former location of this site in the nearshore zone of a marine embayment.  In future work these results could be used as a physical foundation for evaluating the possible role of terroir in controlling aspects of the flavors expressed in Marquette wines from these two vineyards.

How to cite: Munroe, J.: Application of the Vineyard Geologic Identity Concept to Two Marquette-producing Vineyards in the Champlain Valley, Vermont, USA, EGU General Assembly 2021, online, 19–30 Apr 2021, EGU21-13467, https://doi.org/10.5194/egusphere-egu21-13467, 2021.