Environmental determinants of plant species diversity in organic and conventional vineyards

Abstract

The factors affecting the plant biodiversity in organic (manure application) and conventional vineyards (variety “Agiorgitiko for both) in southern Greece were examined separately for each vineyard type. The index for plant biodiversity was chosen to be the Shannon one (SH). The Pearson correlation coefficients disclosed that the common factors in both vineyards types affecting the SH were the concentrations of the soil organic C and organic N, the nitrates –N, the available (Olsen) P, available Cu, exchangeable K and the CaCO₃ percentage. The C/N ratio in soils affected positively and significantly the SH index in both vineyards types. That means that the supply of N is not a problem with regard to decomposition but the organic C as a source of energy can be a limiting factor to plant diversity. The earthworm population density in the two vineyards types was also a significant positive factor to the SH. The concentrations of the available Mg, Zn and ammonium-N in soils affected the SH index significantly only in the conventional vineyards although their concentrations in soils did not differ. We can conclude that chemical fertilization can also affect plant variability.

Keywords:

• biodiversity
• fertilization
• manure
• Shannon index
• soils
• vineyards

Acknowledgments

We would like to thank everyone who has supported us to reach our goals and especially all the farmers for allowing us to carry out the experiments in their fields. The authors would also like to express their sincere thanks to H. Mitropoulou for her help with the analytical work.

Conflict of interest

No conflict of interest was reported by the authors.

Additional information

Funding

The research in this work was funded by the European Social Fund and National Greek Resources in the framework of the Action “Agroetak”. This Action concerned funding of innovative ideas of self-employed PhDs, not employed by third parties, to design and implement Research and Technological Developmental Innovation projects of applied research in agriculture and training of these results to final beneficiaries of the production base (farmers, businesses, members of public administration and other stakeholders).