A journey back in time through the woods

A journey back in time through the woods

Have you ever wondered what forests were like in the past? If suddenly a Templar travelling on horseback through a forest were to cross a rift in time and appear in the same forest today, would he notice difference? Would he see something strange? He probably would. And the fact is that the management of our forests and the relationship we establishwith them has evolved or changed over time.

“Kingdom of Heaven” frame

At the beginning of Ridley Scott´s film “Kingdom of Heaven”, there is a scene shot in the Segovian forests of Valsain. In a fight that takes place on the banks of a river, the backdrop is an almost monospecific forest of Scots pine (Pinus sylvestris). Would it be strange to find 12th century Templars in a forest of this species? Not at all. In fact, we know that it is a species widely distributed throughout the northen hemisphere over time and quite abundant. But, despite being a native species, it is not a natural forest, as the distribution of tress seems to have certain “order”.There is a relative abundance of fairly young exemplars (the trunk is not very large in diameter) growing close together, with very little space between them. Behind this distribution is the hand of man, and in a productive system such as the Montes de Valsain, trees are planted in such a way that they grow tall, straight and as quickly as possible. Furthermore, the scene takes place near a river, where we might expect a riverside forest, but instead, this type of zonal forests has been displaced to favour the growth of conifers. It is therefore a forest under forest management.

But this management isn´t something relatively current at this time in Segovia. There are, in fact, documents that accredit management policies dating back to the 16th century: in an order issued by the crown, it was specified that

“”that all the dug-up areas be levelled and that horse manure be poured in, and that all the trunks of the felled pines and oaks be uprooted and removed (…) and the resulting pits be levelled ” 1

We can say that,for several centuries, management strategies aimed at soil conservation, pest management and obtaining raw materials have been applied in certain forests in our country.

Meadows are another good example of “artificial” forest that responds to the human management throughout history. And in this case, it is even older: our most emblematic landscape, which occupies some 4 million hectares in the Iberian Peninsula, dates back to the Paleolitic 2.

But it has been in more recent stages of our history that the most dramatic changes in forest management have taken place. Traditionally, the forest has been a source of wealth, food and energy for towns and cities, which in itself meant sustainable management. In many cases, need generates dependence, and dependence is what drives conservation. However, the rural exodus to the cities, the appearance of new alternative materials to the use of wood, new forms of energy, or the introduction of exotic species for industrial exploitation, led to a change in the management of forests and agricultural land, which has contributed to the deterioration of the rural landscape, the health of the forests and the lack of protection of the soil.

There came a time, therefore, when there was a need for organised forest management planning, a common strategy based on forest knowledge, the green economy and sustainability. In response to this challenge, the first forest governance bodies and tools emerged in the mid-19th century. During this period, for example, some figures were created, such as the Forestry Catalogue (1862), the First Forestry Law (1865) or the Public Forestry (1989) 3 .

Public mountain in resin in Sierra de Gata (Cáceres), image taken during the Technique Meeting celebrated in the framework of the FIREPOCTEP project the 6th september 22.

Some of these tools are still in use today. But iberian forests are facing a new challenge that is motivating the need for a major change in forest management strategies. Climate change is putting the survival of our forests to the test and calling into question the way they are managed.

Larger forest fires are becoming more frequent and virulent. The accumulation of drier fuels, vertical and horizontal continuity, and persistent low humidity and intense heat make the spread of fire intensify and render the fire inextinguishable. On the other hand, forest pests and diseases proliferate more easily in individuals weakened by heat and drought (or fire) and spread to new geographical areas due to climate change.

Fire at the national park of Bitterroot 4

And how do we face the future? We need to make changes in management and management strategies that are able to respon to the climate challenge of the present and the future. Thanks to technological advances, we have very powerful tools for data collection, modelling and prediction to bring adaptative forest management to a “virtual” level. Satellites, drones or sensors are the new working tools in the forestry engineering with which detailed and almost real-time data on the behaviour of forest can be obtained. But we also need to look back and recover traditional uses of the forest that allow us not only to protect it, but also to generate a sustainable local green economy as the forest did in the past, but with the advantage of being able to apply current technologies and knowledge.

Goats as a tool for controlling fuel in the bush and as a source of local economic resources. Image taken during the Technical Workshop held in the framework of the FIREPOCTEP project on 6 September 2022.c

To this end, it is essential to make progress in research and knowledge of forestry science and other related sciences, so that our forests endure over time and so that the forest that was the setting for historical films is not the setting for a dystopian future

At CARTIF, we work on projects that makes our forests better prepared and adapted to face a future marked by climate change. An example of this is the FIREPOCTEP project, which works to develop forest management strategies to achieve greater resilience to forest fires, while generating resources to support a local green economy. We also work on the early detection and control for emerging diseases, such as Phytophthora spp. in projects such as SUPERA and ForT-HIS.

1 https://www.miteco.gob.es/es/parques-nacionales-oapn/centros-fincas/valsain/estudio_historico_tcm30-81782.pdf

2 https://web.archive.org/web/20070630082614/http://www.dip-badajoz.es/publicaciones/reex/rcex_1_2007/estudios_17_rcex_1_2007.pdf

3 https://www.miteco.gob.es/es/biodiversidad/temas/desertificacion-restauracion/libro75anosdeunailusion_b_tcm30-530962.pdf

4 John McColgan. Forest Service, an agency of the U.S. Department of Agriculture.

Closing the water loop in industry: management and savings

Closing the water loop in industry: management and savings

Water is essential for human survival and well-being and plays an important role for many economic sectors. However, water resources are unevenly distributed in space and time, and are under pressure from human activity and economic development.

In addition to water for irrigation and food production which puts one of the greatest pressures on freshwater resources, industry is also a major water consumer, accounting for between 10% (Asia) and 57% (Europe) of total water consumption, either for the production of its products, and/or for the maintenance of its materials and equipment. All industrial sectors make use of water for industrial processes, ranging from those that manufacture foodstuffs to those that manufacture electronic devices.

Wastewater management is also one of the most important environmental problems facing society today, and is therefore an issue that transcends purely industrial activities, since as a vital substance, water is an ecosystem service that is transversal to most human activities, and whose traceability is heavily regulated by governmental and environmental agencies.

The possibility of reusing industrial water, regardless of whether the intention is to increase water supply or to manage nutrients in treated effluents (also a factor leading to water reuse), has positive benefits that are also the main motivators for the implementation of reuse programmes in companies.

Water Consumption in Industry – Management and Saving Plan

Industries can make better use of water, machinery, processes, services and accessories that demand large quantities of this resource that can be reduced with efficient use techniques.

For each type of industry, water is essential to satisfy different needs, and it is common to prioritise water consumption for cleaning and disinfection of products or installations and equipment. In these cleaning and disinfection tasks, the volume of water consumed varies according to the size, equipment and facilities, and the potential for savings is significant.

Therefore, water reuse should be examined from a circular economy perspective and the opportunities and risks of water reuse in the transition to a circular economy should be investigated for each type of industry.

The objectives of creating a water consumption management and saving plan in companies are:

  1. Define methods to find out the water consumption in the facilities.
  2. Identify strategies and points for improvement in the water consumption actions of the facilities and assess their feasibility.
  3. To implement an effective system to reduce and control this water consumption.
  4. Promote the participation of workers.
Water use in industry

The integral water cycle in industry

The transition to a circular economy encourages more efficient water use and, together with incentives for innovation, can improve an economy’s ability to cope with the demands of the growing imbalance between water supply and demand.

From a circular economy perspective, water reuse is a win-win option. The full cycle of wastewater management is a key component of the cycle, from source, through distribution, collection (sewerage and sanitation systems) and treatment to disposal and reuse, including water, nutrient and energy recovery. Circular economy initiatives aim to close resource loops and extend the useful life of resources and materials through longer use, reuse and remanufacturing.

The selective segregation-correction of segregated effluents from the different industrial activities (process water, cleaning, cooling, boilers, sanitary, etc.) favours the recirculation of water and the reuse of the company’s own treated water, as well as the reuse of grey water. It also minimises water consumption, reduces the final volume of water to be treated or managed and increases the efficiency of the final treatment process.

In general, water reuse requires physico-chemical treatment processes, connections, waste disposal mechanisms and other systems. The level of treatment will depend on the quality of water required for the proposed use.

The implementation of water management and water savings to be optimised is described by means of the 9 elements that make up the integral water cycle in industry:

  • Supply sources: distribution network, own wells, rainwater, etc.
  • Specific treatment depending on the quality requirements for the different types and uses of water.
  • Piping to the facilities.
  • Uses in the process (supply to product, reaction medium, dilution, etc.) and auxiliary activities (cooling towers, steam boilers, cleaning of equipment and facilities).
  • Effluent drainage.
  • Recirculation.
  • Purification (own or external WWTP).
  • Internal reuse.
  • Discharge of wastewater, quality requirement limited by the competent environmental authority.

Water consumption in industry can be rationalised and minimised through various improvements in the production process and auxiliary activities, taking as a reference the application of BATs (Best Available Techniques in relation to integrated environmental authorisations in industrial activities).

As a rule, general actions concern the modification of open cooling circuits into closed ones, the avoidance of losses in steam systems, the improvement of inlet water conditioning systems and production means, and the optimisation of cleaning operations of equipment and installations.

Recirculation is considered if water treatment is not necessary or is very simple, as it involves the successive use of a flow of water in the same process, consuming a small percentage of flow renewal in each cycle.

Internal reuse is the use of water already used in the industry itself, treated by a specific treatment, for other uses that are less demanding in terms of quality or sensitivity.

Non-conventional resources such, as rainwater harvesting, are an easy way to obtain water and do not require purification, but depends on the amount of precipitation in each location. It offers advantages such as high physico-chemical water quality without the need for purification and a simple infrastructure.

The reuse of greywater from showers and toilets with a low level of contamination can be treated into clean, non-potable water.

Operational methodology for optimising water consumption and management

The procedure is summarised as follows:


Data collection and analysis. Request for previous documentation and data necessary for the evaluation of water management.


Visit to the company to recognise “in situ” the corresponding characteristics of the production processes developed, as well as the use of water in the plant.


General description of the production processes and auxiliary activities, identifying the different operations: process line, water line, treatment lines and auxiliary activities (refrigeration, steam boiler, cleaning of equipment and containers and storage).

  • Diagram/plan of water use in the company.
  • Substances involved, raw materials, reagents, by-products.
  • Inventory and description of ancillary activities.
  • Inventory, origin, handling and destination of effluents, wastes and emissions.

Report writing:

  • Diagnosis of minimisation of water consumption and proposal for improvement.
  • Prioritisation of actions according to their performance.

Essentially, the fundamental strategy for the optimisation of water management is the global characterisation of water use, the application of selective segregation-correction of process effluents and the analysis of the possible recovery and utilisation of these effluents.

Optimising water management in industry can achieve savings of 40-50%. This can reduce costs and protect natural resources. Companies should be aware that this increases the social prestige of the company with an economic benefit and promotes sustainability.

REimagine, REcover, ¡RESTORE!

REimagine, REcover, ¡RESTORE!

On June 5th, and as all the years since 1974, is celebrated the World Environment Day. Annually, a theme is choosen to conmemorate this day, in 2022 the choosen one has been “Only One Earth”, slogan shared by the Stockholm Conference of 1972 where the United Nations Environment Programme was created (PNUMA).

REsearching all these information, I´ve stopped at the slogan of the past year, not only because of the theme but because I like words games. In 2021 the known 3R of the recycling were modified (REduce, REuse and REcicle) for making the slogan of the Environment 3R “REIMAGINE, RECOVER, RESTORE”

These 3 words are totally aligned with our daily work but what it seems to me more important, because of the difficulty involved, is the “R” of restore…

When we listen that a space needs to be restore, we tend to think in an abandoned mine, a landfill or any space that is desolated and in which we have to plant a handful of trees to make it again pleasing to the eye.

The truth is that ecosystems recover of all the alterations in a natural way, regardless of whether or not the hand of man has intervened, and even some of these changes are temporal or cyclic natural modifications. Then, when we have to act? The answer is easy, when the ecological balance that allows ecosystems to mature and maximise the services and benefits produced has been broken .

If we really stop to think in the spaces that we degradate or the ecosystems we break we will realise that behind our every steps there would have to be an environment restoration project.

For example, what occurs when we construct a road? We divide a landscape, but well, what is a line in the infinity of the castillian land? Seen like that, nor is it… However, what involvement could this line have in our ecosystem? From the point of view of biodiversity, the effects could be devastators. On which side of the road have animals stayed? And where have food stayed? And water? And shelter areas? And if we have divided a herd?

Environmental restoration projects aim to restore the environment to its original state, but this doesn´t mean that roads can´t be built or wind farms put up or a mine exploited. Environmental projects disrupt habitats for imitate the structure, function, diversity and dynamic that has the original ecosystem including also the visual integration of new elements of the landscape.

Ecce Homo
Source: www.totenart.com

As well as the restoration of work of arts, we have to take into account several factors if we don´t want that our environmental restoration projects end up being as famous as Borja´s Ecce Homo, do you remember?

For the final result to be as expected, it should be very well planified, because this is the most important and decisive stage of the restoration, and should be addressed from an integrator and multidisciplinar point of view. Ecosystems are complex system in which infinity of variables intervene, therefore the planification must be confronted from all the available perspectives: ecology, zoology, botanics, geology, hydrology , engineer…

Once realized the diagnosis of the area, studied the ecosystem , stablished the objectives that wants to reach and the focus that is going to give, should be defined the technique solutions and evaluate the viability of each one, for later design and execute it.

If we continue with the previous example, for the right execution of huge lineal infrastructures , it should have take into account the ecosystem partitioning, and part of its restoration goes through realize wildlife crossings, that not only avoid traffic accidents for collision with animals or track exists, but allows giving those continuity to the fragmented habitat and avoid the loss of associated biodiversity. Design of wildlife crossing, lower or in height, must be made adapting to the infrastructures in accordance with the existing species of the area, as the needs fot he amphibians would be totally differnt that the needs of small mammals or the ones of big mammals.

Lower wildlife crossings, can be built taking advantage and adapting drainage structures, making them more wide and luminous to avoid tunnel efect, and revegetating entries for favouring the approach of animals but do not obstruct dreinage.

Elephants wildlife crossings
Wildilife crossings adapted to elephants Source: www.paisajeo.org
Railway wildlife crossings
Railway wildlife crossings adapted to turttles Source: www.pasiajeo.org

Superior wildlife crossings, in general we know them better, although probably we haven´t noticed them and we think that they are simple bridges or tunnels over our roads. The design of infrastructures has its own technique specifications of wide, acoustic and light insulation, height of side barriers, but also about vegetal and edaphic coverage and access shape for the animals to have a broad view of output and do not perceive they are crossing a high risk area for them.

Wildlife flyover crossings
Wildlife flyover crossings. Source: www.paisajeo.org

If 50 years after the creation of PNUMA we can reuse the same slogan, isn´t because we take the 3R´s of recycling to the extreme, but because we should learnt of our mistakes and restored so that this time yes or yes, let us be “ONLY ONE EARTH” #OnlyOneEarth #WorldEnvironmentDay

Land use planning key in the ecological transition

Land use planning key in the ecological transition

Climate change and environmental degradation represent one of the greatest threats, not only in the European Union, but in the world. In fact, the UN Secretary-General Antonio Guterres stated that “the climate crisis is a code red for humanity and consequently an urgent and coordinated climate action is needed before it is too late”. This entails work on defining effective adaptation and mitigation strategies towards a climate neutral and resilience society, overcoming the current silo approach in favour of a systemic one for evaluating impacts, risks and interactions of climate change across sectors or systems (e.g. Climate, Energy, Land systems).

A system consists of “an integrated set of interrelated elements that works together and interact within a complex socioeconomic framework” (Hoffman and Wood 1976). In particular, the land system (terrestrial component of the Earth system), recently recognised as a “planet boundary” at risk of being exceeded, is the result of human interaction with the natural environment, so that it encompasses all processes and activities related to the human use of land, including socioeconomic, technological and organizational investments, as well as the benefits gained from land (e.g. food, materials, energy, households, etc.) and the unintended social and ecological impacts of societal activities, as for instance, the biodiversity degradation or the energy poverty among others.

In recent years, land system science has moved from a focus on observation of change and understanding the drivers of these changes to a focus on using this understanding to design sustainable transformations through stakeholder engagement and through the concept of territorial and land use planning. So that, it is clear that a better understanding of drivers, state, trends and impacts of different systems helps to reveal how changes in the land system affect the functioning of the socio-ecological system as a whole and the trade-off these changes may represent. Therefore, thanks to the interrelation among land system and the rest the critical systems on fighting the climate change, land use planning is appointed as key even critical tool in the ecological transition.

As you might imagine, Land use planning is not a new concept, regulating land use may have originated about 4,000 years ago in the mud brick cities of Mesopotamia, however from 1980s onwards, Land use planning practises shifted towards an integrated and participatory approach, involving planning experts, decision-makers and citizens.

Especially relevant in the ecological transition, is the planning of land uses in urban areas, since cities dynamics consuming unlimited resources (cities account the 75% of the natural resources consumption), is unsustainable and exceeds the capacity of some essential variables of ecosystems.

Guiding function of urban sustainability. Source: Rueda,S. (1995)

Salvador Rueda1, proposed to consider the city as an ecosystem (formed by interrelated elements among which there are biological organisms), evaluating the efficiency of such ecosystem as the relation between the consumption of resources (E), the number of urban legal entities (n) (economic activities, institutions, facilities and associations) and value of the diversity of legal entities, also called urban complexity (H).

According to this, efforts in cities planning should be focused on establishing a new urban model following the principles of ecosystemic urbanism: improving urban compacity and complexity in its land use organisation, ensuring an efficient use of resources (urban metabolism) and ensuring a greater social cohesion.

In CARTIF, we work on the development of models (at different scales) tools and solutions to support this systemic approach in the transition towards a sustainable use of land, so as to guide decision making Land Use Planning processes and the holistic evaluation of adaptation and mitigation solutions. For instance, in the eParcero project we work to support territorial and land use planning by identifying plots with potential for specific land uses (e.g. industrial development, energy production, etc.), while in the RENERMap project we are developing models for the identification of plots with renewable energy potential (e.g. wind, solar or geothermal energy) that contribute to the decarbonisation of the energy system of our region, through the integration of geospatial climate, environmental and social data in the territorial planning.

Specifically, the RethinkAction project (GA 101037104) coordinated by CARTIF, aims at delivering an Integrated Assessment Platform to simulate and evaluate land use-based solutions at local, EU and global scales over time (2050 and beyond). At local level, a methodology to develop dynamic models in the 6 case studies (representative examples of climate change impacts and land system pressures) will be delivered, by using dynamic modelling methods such as System Dynamics (SD) or Agent-Based Modelling (ABM) along with GIS tools.

Long life to batteries!

Long life to batteries!

From the smartphone we carry every day, the tablet or the computer, till any other portable electric tool we use in our everyday have implicit the use of an electric energy accumulation system, or what is commonly known as batteries, in this case rechargable batteries.

But, we really know what batteries are, what contain or how the materials that make them function can be recovery?

Many times the unknowledge of our environment make us carrying a bad management of some of the elements that surrounds us when they reach their service life.

Before knowing these details, could you tell me how many types of batteries exists nowadays?, we talk about Nickel Metal Hydride, Nikel Cadmium or we focus on lithium-ion, now on everyones´ lips?

  • Nikel Cadmium are used mainly to feed computers, mobile phones and wireless and some varieties of toys, but they are used less and less.
  • Nikel Metal Hydride are a battery variety less harmful for the environment and with a longer service life.
  • Lithium-ion are the batteries with the biggest energy storage capacity in comparison with the previous ones and those that are currently most widely used.

Although this post could go on for as long as some of the encyclopaedias have volumes, those that gather dust on our shelves at home, the initial idea is to get to know lithium-ion batteries a little better and why is necessary to attend the recovery of its materials at the end of their service life.

To understand the importance of this need for materials, it is necessary to understand the dependence of our European continent on raw materials, critical raw materials such as the ones that we found in nowadays Lithium-ion batteries as cobalt, nikel, lithium or manganese. Much of these materials are concentrate in very specific places of the planet, which creates a greater dependence on these.

Right, we already know that exists different types of materials inside lithium-ion batteries, but let´s make it a little more complicated, so it not only exists one type of lithium-ion battery, but, depending on its application, we talk about different chemicals, that is to say, the components that form the different cells of the batteries are based in different materials, quantities and conglomerate, as well as different morphologies. These different, lets say models, are changing since their invention at the end of the 90´s, because of their dependence on raw materials or because of the technological advances. We can count with up to 6 different types of lithium-ion batteries models. And in case you were thinking about it,yes, this will complicate their recycling.

Source: https://enrd.ec.europa.eu/news-events/news/committing-climate-neutrality-2050-commission-proposes-european-climate-law-and_en

We have already assume that we are dependent in terms of raw materials, but, in addition, we have to add the tendence to decarbonization of our energetic system, that mainly at the transport sector is tending to electric vehicle, that as we already know, uses lithium-ion batteries. Europe´s goal is to achieve carbon neutrality by 2050.

Going back to the initial question, we already know which materials make up a battery and that there are many types of them, but in addition we know the need of our european community in terms of reuse of these materials, therefore, we would have to recover those materials at the end of the lithium-ion batteries life service, but, how it is done?

Currently it exists 3 huge methods for recycling those batteries named pyrometallurgy, hydrometallurgy and direct recycling, whose influence over the value chain is next one:

  • Pyrometallurgy: high temperature foundry process, it should be made up of 2 steps: first, batteries are burnt in a foundry, where the compounds are decomposed and organic materials are burnt, such as the plastic and the separator; the new alloys are generated by the ashes carbon reduction.
  • Hydrometallurgy: in this process, the materials recovery is achieve by an aqueous chemistry, through the leaching in acid disolutions (or basic) and his later concentration and purification, by the evaporation or separation of the solvent. Purity and quality of the extracted metals are usually differentiated according to this last purification stage of the process.
  • Direct recycling: recovery method proposed for reaconditioning and recover directly batteries active materials, preserving their oirginal structure.
Source: https://cicenergigune.com/es/blog/reciclaje-baterias-industria-europa

If we pay attention to carbon neutrality, the first method will no longer be feasible at long term, so involves a series of green house efect emissions associated, therefore the most sustainable ways would be hydrometallurgy and direct recycling.

Our wonderful guardians and neighbours!

Our wonderful guardians and neighbours!

People hear a lot about the decline of bees, about the lack of pollinators, but what are pollinators? more importantly, what do they do for us and what do we do for them?

The group of pollinators is very wide, not only honey bees, which belong to one specific family.  In fact, in Spain we have more than 1,000 species of bees from six different families, 75% of bees are solitary and live on the ground and with more than 20,000 species of bees in the world they have evolved and are organised in many different ways.

Other pollinators are birds, mammals and reptiles because plants are very clever – they have been on earth for many millions of years longer than we have! And that results in greater evolution and adaptation. Plants have developed sophisticated methods of attraction to achieve their reproductive purposes because the pollen has to reach its destination! They use everything from lizards to flies and bats, not forgetting air and water, which also help in pollination.

But if there are so many means for pollination, why are pollinators, in particular bees, so important? Well, at least, in this case, size and shape matter! There are all kinds of insects, small, fat, long, with very long tongues, in short, many sizes! Just as there are many shapes and sizes of flowers and pollen grains because plants are very sybaritic.

Plants have evolved in such a way that each one has developed its own system, some of them very exclusive, to avoid pollen from other plants, that is why there are so many smells, to make a first selection of “be my guests!”; and many sizes, some bees have to stick out their proboscis or “tongue” up to 20mm to get to the food; some, like the passionflower, have very large stamen and pistils, and can only be pollinated by large bumblebees; others are complicated, like the snapdragon flower, where the bee has to get inside as if it were a cave; and others are smaller, like daisies, which need a small insect and are therefore pollinated, for example, by small black and yellow striped flies, which are the hoverflies. The sunflower is a large daisy and therefore needs a larger pollinator such as the honey bee. There are thousands of families of bees of different sizes, ranging from 4-5 mm to 30-35 mm (honey bees measure between 15 and 20 mm).

Both flowers, sunflower and daisy, have large yellow or white “petals” around them (which are actually ligule) and a bunch of little yellow flowers in the centre from which the seeds come out (which in sunflowers we call pipas). Next time you pass by a park, pick up a daisy and look closely at the yellow part, they are all little flowers! With their stamens, stigmas and all the parts of a flower that we hardly remember from when we studied them at school!

Cut of solitary bee nest. Source: Luis Óscar Aguado

Colours are another attraction mechanism for pollinators to detect them from far away! With our eyesight, all colours look the same to us, but with their special vision, they see the colours of the flowers differently. In the end, plants have made insects and pollinators evolve as pollen carriers, and in return, they provide delicacies in the form of fruit, seeds, pollen, nectar, etc.  As you can see, there are numerous mechanisms to attract the right pollinator, so if the population of one disappears in a short period of time, the plant cannot adapt and even less reproduce.

Bee laying an egg on a bamboo cane. Source: Maria González

Many pollinators obtain food rewards from plants, but they do not feed exclusively on them like reptiles or birds, but bees do, they depend exclusively on plants for food. Both their larvae and the adult insect feed on floral products such as nectar and pollen. And as we have seen, not all flowers feed all pollinators.

So how can we help pollinators?

We can build them a shelter, depending on the family of bees they have different forms of housing or social grouping. Some build galleries in the ground where they live, so placing a pot in the window is enough; others in holes in logs or pieces of wood, even shells!. So a simple and space-saving way is to put up a hotel for solitary bees. It is very simple, consisting of a bundle of cut bamboo canes or a piece of wood with holes of different diameters between 5-25 mm, with a base, that is, that does not go through the wood and without cracks, as these are possible entrances for parasites and predators. There the bees will lay their eggs, which they will leave with the nectar or pollen collected and cover it up, and after a year the new bees will leave and go and look for another hole. So there is no danger of being stung. Bees don’t live there, they just lay their eggs, they are solitary, they don’t form hives, they don’t form communities, they sleep on flowers and branches.

Solitary bees don’t sting! Well yes, but not like honey bees, I mean, many bees die when they sting you, solitary bees do not form communities, as they do not have to defend it, they are not aggressive, they do not attack, they do not sting, this makes it a good idea to install this type of shelters in schools, children can get close and see how many holes are plugged, and count the bees they have helped.

Also, these bees only collect food for their own food and larvae, so they don’t need to collect so much, others need food to raise all their offspring, and others need food for the whole colony and humans, so if you disturb them with your hand, most of them leave, they don’t want trouble, attacking you costs them their lives, but others are more insistent because they need a lot of food and the closer you are to the hive, like the honey bees, the more aggressive they can become and attack.

Pollinators hotel
Bee hotel with two holes fulfill located in CARTIF. Photo: María González.

This is why there are special regulations for keeping beehives, which are considered a type of livestock farming (beekeeping or honey farming) and have to comply with requirements regarding distances to populations, etc. It even has to respect the distance between them, since, if there is little food, it attacks other pollinators, such as solitary bees, as they are competing for food.

It is also important to have flowers all year round, for them and for us, there are many native plants with different flowering periods so that they have food all year round, in different sizes for bees of all sizes.

How do they help us? The best-known part of the work of pollinators is that of pollination. 80% of plants depend on them, and many of them are responsible for providing us with food. 75% of crops currently need pollination, and this includes the crops needed to feed livestock, so the production of livestock by-products also depends on them.

Pollinators module, module with flowers during all the year located in CARTIF. Source: María González

Pollinators are therefore our allies, and it is thanks to them that a large part of natural and urban plant communities and our food is maintained. Climate change, pesticides, agricultural intensification, the continuous clearing and mowing of parks and fields, including the proliferation of beehives, are causing their population to decline rapidly. Moreover, we still have a lot to learn about them, so it is very necessary to help them consciously and rationally, and not only at the level of experts, but also at the social level, all of us can help their conservation, taking care of pollinators and cultivating more flowers around us, since without flowers there are no pollinators and vice versa.


If you want to know more you can consult the websites of great professionals such as www.lepidopteros.com and www.abejassilvestres.es

Bibliography: Curro Molina & Ignasi Bartomeus. 2019. Guía de campo de las abejas de España. Esditorial Tundra, Castellón. 250pp. 19’5 x 12’5 cm. ISBN 978-84-16702-77-0.


Photos: óscar Aguado and María González.