This system was supposed to be installed in the south of Itlay, a circumstance that never came to be, as the regionals Rural Development Plans’ founds did not consider at all out-of-soil agriculture.
The last part of this proposal is focused on the specific geographical benefits for Puglia (my native region), but I am sure that many of the points made in the document are still globally relevant and can be easily retailored for the specific requirements of many other places.
The project proposed is an integrated agricultural system that is composed by a hydroponic and aquaculture (aquaponics) recirculating cycle, and a separate insect rearing unit.
Aquaponics is the integration of hydroponic plant production with aquaculture, two of the most productive methods in their respective fields, combining them into a sustainable agricultural integrated and virtually closed system.
Such system (RAS: Recirculating Aquaponic Systems) uses the recirculating water from the fish rearing tanks, full of metabolic wastes, which are a source of nutrient, to aid the production of the selected crops in the hydroponic section, a process that subsequently removes toxic substances for the fish. This creates a natural biological cycle that:
- Supplies nitrogen to the crops;
- Minimizes the use of non-renewable resources;
- Maximizes the value of by-products, thus providing economic benefits that can increase over time.
This integration has numerous advantages, that can tackle key issues the current, both global and local, agricultural landscape, and it is deemed by multiple renowned sources, as a viable, sustainable, and efficient production system. Let’s take a look at these benefits in more detail:
The first evident benefit is the extremely efficient use of the primary resource of this kind of system: the water.
Water use is maximized, which means that its consumption is significantly reduced in comparison to traditional agriculture and aquaculture systems. Estimates account for water savings that range between 80% and 90%
Furthermore being a closed system, the input requirement is very low and, during standard operation, the system needs only to accounts for natural evaporation and plant uptake.
Avoiding using soil for crop production has a direct positive impact on the soil itself.
An immediate consequence is that the set-up of a RAS facility, does not require any preparation to the soil itself and it can (and should) be implemented in areas where the composition or fertility of the soil does not allow for traditional means of production, such as:
- Non-Arable Land;
- Urban Areas;
- Degraded or High-Salinity Soils;
- Even Deserts.
Another direct benefit is that nutrients are not dispersed in the soil, which means better control and a better delivery rate of such nutrients, which also drastically reduce the risk of contamination and soil erosion, even in the case of intensive monoculture.
Improved Produciton and Yield
Production of crops and fishes is maximized, and the production cost is contained.
- Fish yield is improved, thanks to the higher fish density allowed by the recirculating water system and to the controlled rearing environment.
- Crop yield as well is increased up to 100%, with respect to conventional horticulture due to various factors:
- Higher plant density and decreased nutrient competition;
- Better environmental and climate control of the growing conditions, which also leads to better quality, more marketable, products;
- Shorter production cycles and higher number of harvest per year;
- Less (near zero in optimal condition) impact of external pathogens.
Operating Cost and Labour
Even if an aquaponic system requires constant monitoring, with relative adjustment to the requirement of its various components (mainly water quality and filter efficacy checks, fish feeding), it is deemed to have very light labour requirements.
Furthermore, many of the main daily operations required could be efficiently automated and digitalized. Especially regarding the monitoring operation, resulting in significant labour intensity and time savings.
Organic by Default
By its own characteristics, an aquaponic system is inherently organic by default and easily maintained so. Making it easy to obtain organic certification, which will improve the final product overall value and its market potential.
In addition to these inherent benefit of the RAS, there are further features that, when implemented at the design stage, can improve their efficiency and environmental and economic value.
There are various viable ways to implement such systems, but one of the most diffused is the enclosure of the entire RAS facility into a greenhouse. This poses various benefits. It allows for example for a higher degree of environmental control allowing year-round growth at optimum rates increasing at the same time the level of Biosecurity and lower risk from outer contaminants.
Reducing the input
Water, energy, and fish feed are the three largest physical inputs for aquaponic systems.
As already mentioned, the water input, in optimal conditions, is minimal (one of the key benefit of such systems).
As for the energy input, it is key for the survival of the entire system. It is required continuously for the correct function of the water and air pumps that keep the recirculating system flowing. This input requirement can increase if the system also uses additional mean to control the growing environment: for example, growing lights and temperature and airflow system in greenhouses.
However, energy input cost can be reduced, at the expense of a slightly higher initial investment, by employing alternative, sustainable, energy sources (solar, wind, biofuel, etc…). A more desirable choice because it helps to further reduce the carbon footprint and contributes to the overall added value of the final product!
Fish Feed (Nutrients)
The last input required, therefore a component of the operating cost, is the fish feed. Feed is essential because is the source of all the nutrients (principally nitrogen) used by the system, substituting more expensive commercial hydroponic nutrient solutions. It needs to be carefully quantified to fit the system requirements and it represents one of the most expensive input. Here is where the insect rearing component of the project becomes relevant:
Insects are a healthy nutrient source because they are rich in protein and polyunsaturated fatty acids and full of essential minerals.”“Small-scale aquaponic food production: integrated fish and plant farming” – FAO
Insect Rearing Unit
Insects have been identified as one of the few sustainable alternatives capable of feeding the planet in the future. And their adoption in the “West World” is growing slowly, but steadily, with a sudden surge of interest in the last few years, trend that is believed to endure.
Aquaculture and Insects as feed
Aquaculture, as a source of fish supply for human consumption, in the last 3 decades, increased its share compared to wild capture, fulfilling up to about 50% of the global fish demand. To support this unprecedented growth there has been a corresponding rise in the demand, production, and price of fish meal.
Fish meal comes primarily from discarded fish stocks of wild-caught marine fish, which, is one of the leading reason behind the incumbent issue of overfishing and marine biodiversity erosion. Fish meal is used not only in aquaculture but also in much other traditional livestock farming (Poultry and swine mainly).
A lot of effort is being put to find an alternative, more sustainable(both economically and environmentally), feed source that needs to be rich in protein and lipids. And insects, in particular species like house flies, black soldier flies, and crickets have been identified as one of the most promising, sustainable, substitute or complement to fish meal and their viability as animal feed has been evaluated in may studies. Their feasibility is especially a direct consequence of their high protein and lipid content which is essential to the fish development and meat quality(Dossey et al., 2016; Surendra, Olivier, Tomberlin, Jha, & Khanal, 2016; van Huis, 2013a, 2013b, 2017).
Next, are explained some of the more significant benefits of using insects as a protein source: the first three, tightly connected to each other, have a more specifically environmental dimension, while the last three also are associated with compelling economic advantages:
“Food production takes up almost half of the planet’s land surface and threatens to consume the fertile land that still remains”Insects as sustainable food ingredients: production, processing and food applications. – A.T. Dossey et Al.
Better management of the land and soil’s resources is a key factor in building a more sustainable future.
Insects can easily be reared in controlled, indoor, environments that make extremely efficient use of the vertical dimension, increasing the productivity per m2 and avoiding the erosion and exhaustion of fertile soil.
To yield, for example, an analogue quantity of protein produced in 1 ha of land by mealworm rearing, milk protein would require 2.5 ha, chicken and pork around 2–3.5 ha, and beef requires up to 10 ha.
Gas Emission reduciton
In comparison to other conventional livestock farming, insect rearing produces far less ammonia and greenhouse gases!
Estimates differ from species to species, but insects perform overall better regarding emissions. Ammonia levels, due to insect farming, are lower than for pigs and beef cattle.
For example, crickets (Acheta Domesticus), which are associated with the highest ammonia emission, still produce just around the 10% of the ammonia produced by pigs (calculated as mg of ammonia per kg of mass gain) and an irrisory amount compared to beef, which produce 2 to 3 times more than pigs. Crickets, moreover, along with migratory locusts (Locusta Migratoria) and yellow mealworms (Tenebiro Molitor) (which are currently three of the most reared species intended for food and feed), do not produce methane
The water use, also, in comparison to other livestock, is drastically reduced as insects obtain their water directly from food and have lower feed requirements
When we consider the water needs per gram of protein, this is smaller even compared to plants (Costa-Neto, 2014; Shelomi, 2015; Soares & Forkes, 2014) Lower water usage also reduces the energy needed to pump or recycle more clean water for crops and vertebrate livestock
Short Cycles and Feed Conversion Efficiency
From a more economic point of view, the main benefits of insect rearing are that their short life cycles and their extreme efficiency in transforming feed into protein and nutrients.
This short life cycle, which it can also be further optimized in a controlled environment, means improved productivity, which, along with their general inexpensiveness and relative easiness to rear, makes insect very cost effective to farm.
The environmental benefits of rearing insects for food and feed are founded on the high feed conversion efficiency of insects.Edible insects: future prospects for food and feed security – FAO
Organic Side Streams
One of the most important features of insect rearing is the possibility to use organic side-streams, which can help reduce environmental contamination and tackle the issue of food waste.
Globally, one-third of all food produced is wasted, amounting to 1.3 billion tons per year.
Organic side streams are the result of bio-waste produced by agriculture, forestry, and households. Their use can aid in the reduction of the already low costs and environmental impact, of large-scale insects rearing and can create an alternate potential income for agri-businesses.
In 2018 shall enter into force the EU regulation on Novel Foods, thanks to which insects food products, along with other food innovation (i.e. algae-based products), will be freely produced, sold and bought in all the EU states, with all the food safety guarantees that the EU and the EFSA provide.
In the last few years there has been an unrelenting growing interest in this field accompanied by increasing investments: in America, millions of dollars have been already raised by insect food and farming companies and January (2017) the Netherlands-based insect farming enterprise Protix, a has raised €45 million, which is the largest investment on edible insects to date. Furthermore, such products are already present in the market.
This means that the set-up of an insect rearing farm, not only provides the many aforementioned benefits but can also create the opportunity to be an early actor and enter more easily the novel, developing, the market for insects used as food, for human consumption!
Opportunity for Puglia
So even in the name itself water has always been an issue for this territory, which is characterised by an inherent lack of bodies of water, and already categorized as a semi-arid; circumstance that stays particularly critical because of its agricultural disposition: Puglia has most of the agricultural related business of any other Italian region, with a significant percentage share: 16.8% of the national total.
In Puglia, and in Salento especially, almost the entirety of the plots of land dedicated to agricultural activity is rural with many development barriers and most of its water resources are supplied from groundwater: around 75% is supplied by private wells.
Climate change is already affecting the frequency of drought events which may threaten the current stocks of water resources and thus the availability of freshwater for irrigation.
This happens, not only at a regional level, but it has a national and global scale. In the last years, the occurrence and the magnitude of droughts and water scarcity in Italy it is becoming more and more frequent and severe: pertinent is the current problematic condition, that gained vast media coverage in summer 2017, of Lake Bracciano, which is the main water resource of the Lazio Region.
The region’s governance already recognizes this as one of the most critical aspects of its agricultural development.
Therefore, one of the key requirement to improve Puglia’s agricultural landscape is to:
Modernize irrigation equipment and techniques (including conventional and non-conventional water storage structures); facilitating productive conversion towards species or cultivars with reduced water needs according to territorial compatibility and through changes in farm plans and farm systems.”Regione Puglia, 2014
To which the integrated system here proposed completely adheres. The 90% savings, considering equal productivity, that this system provides could be crucial to contrast the impelling issue of Puglia water scarcity, enhancing the overall regional water efficiency, and, at the same time, maintain and further expand Puglia’s competitiveness, at a national and global level, in its main economic sector.
Water in Puglia
At the national level Puglia owns the smallest amount (136 m3/capita/y) of potentially available water. The agricultural (and touristic) vocation of the region is only possible thanks to the local water agency (AQP) that imports water from bordering regions such as Campania, Lucania and Molise.
Every year in Puglia around 1.500 Mm3 (Cubic Megametres) of water are consumed of which around 54% (812 Mm3 ) are dedicated to agricultural activities (while 36% as drinking water 10% for industrial use).
This water comes from the 55% from the local regional delicate aquifers. Percentages that rise significantly during water crisis and draughts. The reuse of agricultural (or else) wastewater is still very marginal. Such water crisis and draughts are periodical, and their severity is becoming more worrying year after year. The extension of Puglia’s irrigated land stands at 240.000 ha, equal to 18,6% of the overall UAA, spread on 67.000 farms. The main mean of irrigation is the use of drip irrigation systems, followed by sprinkling (respectively 52% and 32% of the total), which underlines
Soil is increasingly degrading, both in the EU and at a global level and soil erosion by water is one of the most widespread forms of soil degradation in Europe.
As mentioned, a great share of the water used by the agricultural sector (75%) in Puglia, comes from private wells, which is the traditional source of water supply in the region. This drawing of groundwater is, unfortunately, considerably uncontrolled and not properly governed, with severe consequences on the progressive salinization of the aquifers and the soil.
Puglia soil erosion degree (8%, 2016 data) is slightly higher of the national average, also due to the high impact of monoculture. Between 2015 and 2016 414 ha of land have been lost, 1 m2 every 5 seconds.
Estimates say that for each inhabitant there is 400 m2 of spent soil and, in Salento especially, numerous municipality has spent soil for 20% of their entire area (ISPRA, 2017b; Regione Puglia, 2014). The main causes of soil erosion in Puglia are related to salinization and predictably the areas more affected are the one dedicated to intensive cultivation and the subsequent use of chemical compounds in spite of organic fertilisers and enhancers (such as quality compost, manure, etc…).
Therefore, an efficient agricultural production system that does not use the soil would be crucial in preserving this precious resource, with no issues of salinization or nitrification.
Moreover, this integrated SOIL MANAGEMENT system can (and should) be installed on an already exhausted, or otherwise infertile, patch of land. It can also contribute to the restoration of the richness of the soil itself by increasing its organic matter composition, thanks to the possibility of producing organic fertilizers, derived from the mineralization of the organic waste generated inside the system.
Soil in Puglia
Puglia’s territory is spread on a surface equal to 1.954.090 ha, which corresponds to the 6,46% of the entire national surface.
It is composed of mainly plain land and low hills, with very few mountainous relief. In the plain area are situated the majority of its municipality (70%) while the rest are on the hills (27%) mountains (3%) areas.
To agriculture’s activities is devoted a great share (83,2%) of its territory. The UAA in Puglia, in 2010, was, in 2010, equal to 1.285.290 ha, in particular, 51% of this land is dedicated to arable crops, 8% to pasture and livestock, and 41% to woody plants. Even if, the highest share of land is reserved for yearly crops, permanent crops, namely olive trees and vines, have the greatest economic impact. Urban areas represent 4,6% of the territory. Areas that are vulnerable to nitrate contamination are stretch across a surface of 89.359% ha, around 4,6% of the overall region. Nonetheless monitored nitrates levels in aquifers are stably beneath the legal threshold of 50mg/l NO3.
Soil can be considered a non-renewable source and, among its various function, it is fundamental in supporting biodiversity. Thus, soil management is essential; in contrasting biodiversity erosion. Along with soil erosion other cause of this loss of biodiversity are global climate change, intensive agriculture and the decrease of commercial relevance of more traditional crops.
Estimates say that half of the world’s biodiversity has been lost in the past 40 years (Shmelev, 2017). The south of Italy is still a centre of diversity for several crops but modern cultivars are progressively replacing them and invading their landscape.
In the Salento area, Tremendous genetic erosion is evident since the 80s and widespread in the past 25 years, therefore the region is trying to safeguard its botanic richness.
A portal, “biodiversitapuglia.it”, has been established to help catalogue and monitor local cultivars; 14 crops have been found to be at risk of genetic extinction (“Il Progetto BiodiverSO,” 2017).
Furthermore, in the regional Rural Development Plan for 2104-2020, the preservation of biodiversity has been made one of the priorities (Priority 4): to preserve, restore and enhance the agricultural ecosystems. It is stated that:
“The agricultural areas represent an important factor in the conservation of the biodiversity because they are potentially capable to provide an analogue function as natural forest and fallow do. ” Also, growing attention is given to consumer demands, which are increasingly going toward the selection of goods produced with sustainable and safe methods. The system proposed, mixing agriculture and aquaculture appears an interesting solution to this compelling issue, as it could preserve biodiversity and, at the same time, raise productivity (Pantanella, 2010).
A good example is the case of “mugnoli”, a particular cultivar of broccoli (Brassica oleracea var. Italica), which can be considered, as stated in Laghetti’s (2005) work on this crop, as “an early step in the evolution of broccoli”. This surviving crop, present in only a small portion of Salento, is proof of the regional biodiversity richness. A particular problem that local growers face, is the natural contamination, through natural pollination, of other broccoli cultivars.
“Its [of “mugnoli”] typical flower colour is white; sometimes in the field some plants with yellow flowers appear as a token of the genetic introgression from extraneous Brassica spp.; during the seed production all the single selected plants are covered by a net to avoid undesired genetic introgression but, in any case, traditionally, farmers eliminate plants with yellow flowers.”Laghetti, G., Pignone, D., Cifarelli, S., Martignano, F., Falco, V., Traclò, B. R. G., & Hammer, K. (2008). Agricultural biodiversity in Grecìa and Bovesìa, the two Griko-speaking areas in Italy. Plant Genetic Resources Newsletter, (156), 57–61.
By hypothetically using the suggested aquaculture agricultural system to grow this particular crop, such issue stops being relevant, as the soilless indoor (in the greenhouse), controlled cultivation, will protect the crops from external contamination and, at the same time, safeguard its survival, by assuring its efficient production.
Full Proposal Document
For more detail, further informationa and the full list of references, please thake a look at the full proposal: