Gross and net primary productivity in a vineyard assessed by eddy covariance and biometric measurements

CALLESEN, T.O.; GONZALEZ, C.V.; CAMPOS, F. BASTOS; ZANOTELLI, D.; TAGLIAVINI, M.; MONTAGNANI, L.

ACTA HORTICULTURAE

International Society for Horticultural Science

Año: 2022 vol. 1355 p. 423 - 429

0567-7572

Vineyards represent a relevant land-use type in the Mediterranean region. They present perennial woody plants (vines) and often herbaceous vegetation in the alleys and sometimes under the vine canopies. To which extent these features are posing the vineyards in terms of carbon balance is still unclear. While some studies suggest they could act as large carbon (C) sinks, others indicate a minimal capacity to sequester carbon. Carbon sequestration involves both, C fixation and allocation. To elucidate the specific features of carbon fixation and allocation we established an eddy covariance station in an organic farm in South Tyrol (Italy). Two vine cultivars (‘Chardonnay’ and ‘Sauvignon blanc’) are cultivated. Vineyard alleys are either naturally grassed or covered with cover crops, vines are drip irrigated. In addition, we regularly assessed the above ground net primary productivity (ANPP) of the vine and grasses. The diurnal pattern of gross primary productivity (GPP) followed the bell-shaped pattern of global radiation, with relatively higher values in the morning as compared to the afternoon. GPP was highest during the summer months, with the exception of June, probably due to scarce precipitations. Cumulated GPP (photosynthesis) from mid-April to mid-November (2409±35 g C m-2) was unexpectedly high and similar to the most productive broadleaves forests in temperate regions. In the considered period, the aboveground net primary production was 968±104 g m-2 dry matter. Most ANPP (53%) derived from the growth of the partially sown herbaceous vegetation in the alleys, that were managed to enhance the soil organic C and the soil quality. The ongoing research will assess the contribution of belowground plant organs and the overall carbon sequestration potential of the experimental vineyard.