Javier López, Phd in Biology, explains the importance of phenology and islands of vegetation as part of the Poll-Ole-GI project

Javier López, a doctor of Biology, is one of the researchers working on the Poll-Ole-GI SUDOE project as a member of the group that has been established at Burgos University. He explains his role in this project: the study of phenology, i.e. when plants flower and their efficiency as part of islands of vegetation. He also tells us of the importance of these islands of vegetation within the ecosystem into which they are introduced. 

What is your role in the Poll-Ole-GI project?

It mainly involves the follow-up of the various islands of vegetation. As part of the project I carry out phenology studies, i.e. I work on when plants flower or at what time of the year they begin to bear fruit so as to subsequently discover the actual effect of the flower on pollinators. The existence of islands of vegetation is of vital importance if bees are to obtain food during the period when there are no traditional flowers.

What action have you taken as part of the project?

I have taken samples, measured plots, and gathered plants from the islands. These plants are brought to the University so we can analyse what other species have appeared other than those we have sown. In this way we can find out which species from the islands of vegetation do not correspond to those that we have sown there. Above all, we can appreciate the evolution of the vegetation.

Not many of us from Burgos University are involved with the Poll-Ole-GI SUDOE project, which means that we try to work together on all the tasks that it covers. To do this we establish groups and visit the islands so as to assess the vegetation and take samples. We have been observing the evolution of plants in our research garden at the Escuela Politécnica.

What process was followed in the implementation of the islands of vegetation?

Firstly we designed a research garden at the Escuela Politécnica. We created different margins of vegetation 5 or 10 metres wide which are separated by corridors and we sowed different floral mixtures so as to be able to compare their behaviour over time.

Every 8 or 10 days we observed which of these species had come up and which were at the seedling stage, but our main interest was the estimated flowering time. For example, we established whether the flowering of the marigold or the sage was starting and how long it lasted to find out their biological cycles.

We also followed the same process on nearby islands where we finally carried out our practical research; we had planted sunflowers there and assessed the situation. In addition to sowing these species, we added compost to one half of the island but not to the other so as to make a comparison. As is logical, some species came up that we had not planted.

We then assessed the pollinators and the plants that had sprouted. The spontaneous vegetation that appears is generally nitrophile because we were introducing it on a site where farmers add a great deal of nitrogen to the soil. It is therefore logical that this type of vegetation will appear although it has nothing to do with the species that we plant; they also contribute towards the establishment of pollinators.

What were the conclusions that you drew from this practice?

We have been observing the process throughout the course of the cycle. During the summer we watched the initiation of the flowering and its escalation so as to be able to compare the pollinators. What we did in the end was to take samples to assess the biomass and the species that had appeared. The method used was the traditional one of defining a square and assessing four different areas in each part of the different islands. This method allowed us to assess the biomass and find out what species appeared.

Our aim was to apply the Braun-Blanquet phytosociological method which consists of determining an index of the abundance and dominance of species and also a sociability index. This was very difficult because some species grow in isolation but occupy a lot of space, such as Borago officinalis. The next step consists of drying these samples in the laboratory to analyse the biomass that the different species have generated.

Why is this plant variety selected rather than others?

They are a variety of melliferous plants and of great importance from the point of view of pollinating species. This is a commercial mixture from the Syngenta company which is not only used for this purpose but also as plant cover. It is planted in olive groves and vineyards so as to prevent aridity; this cover reduces the strength of the vineyard so that production falls. Later at a given moment the life cycle of these plants is completed and they act as biomass that is included in the soil.

On the one hand, biomass is obtained and on the other, food is provided for pollinators. Moreover it is extremely useful as the flowering occurs in a staggered manner. Some of these plants such Sinapis alba subsp. mairei have been registered by the Andalusian Institute for Agricultural, Fisheries, and Food Research and Training and Ecological Production (IFAPA), which is a section of the Ministry of Agriculture, Fisheries, and Rural Development of the Regional Government of Andalusia, and are mainly used as plant cover and for biofumigation.

They are doing the same as we are, studying the germination percentage, the flowering period, and the phenology when flowering is at its height. Logically, however, its behaviour varies from Andalusia to Castilla y León. It also serves to increase biodiversity.

What effects does this have on the ecosystem into which it is introduced?

Inevitably there are many as pollinators are decreasing. When we establish these islands of vegetation we help pollinators to be present at a time when there are no plants related to farming activities, so that they can feed and maintain their life cycle. In this way the population will be much higher at the beginning of the pollination season, and a stable population is established that is able to reproduce thanks to this wild flora. We also carried out another study in which we installed nesting boxes to find out the number of these insects that were capable of nesting and producing descendants.

An example of the importance of pollinators to the ecosystem is that in Almería farmers have already installed nesting boxes for bumblebees on their farms. They know that without these insects their tomato production falls. The same thing occurs on many other plantations, for example sunflowers and any others pollinated by insects.

What will be the next actions of the Poll-Ole-GI project?

After studying this first stage we will decide whether to continue with the same mixture or to change to another. It is important to establish islands in which these aspects and the traceability of phytosanitary products, can be monitored. These products will not be used in some of the areas; this is essential as they affect the pollinators on which we depend to live.

Photo – Javier López, Phd in Biology and member of the Poll-Ole-GI project