Exploring the production capacity of rooftop gardens (RTGs) in urban agriculture: the potential impact on food and nutrition security, biodiversity and other ecosystem services in

CASE STUDY

Exploring the production capacity of rooftop gardens (RTGs)in urban agriculture: the potential impact on food and nutritionsecurity, biodiversity and other ecosystem servicesin the city of Bologna

Francesco Orsini & Daniela Gasperi & Livia Marchetti &Chiara Piovene & Stefano Draghetti & Solange Ramazzotti &Giovanni Bazzocchi & Giorgio Gianquinto

Received: 3 April 2014 /Accepted: 15 September 2014# Springer Science+Business Media Dordrecht and International Society for Plant Pathology 2014

Abstract The present work, focusing on the theme of foodproduction and consumption in urban areas, analyses therelationships among three factors: city, human well-beingand ecosystems. A case study was carried out addressing thequantification of the potential of rooftop vegetable productionin the city of Bologna (Italy) as related to its citizens’ needs.Besides the contribution to food security of the city, thepotential benefits to urban biodiversity and ecosystem serviceprovision were estimated. The methodology consisted of: 1)experimental trials of potential productivity of simplified soil-less systems in rooftop gardens (RTGs); 2) detection of all flatroofs and roof-terraces and quantification of the potentialsurfaces that could be converted into RTGs; 3) identificationof the city’s vegetable requirements, based on population anddiet data; 4) calculation of the proportion of vegetable require-ment that could be satisfied by local RTG production; 5)identification of other benefits (improvement of urban biodi-versity through the creation of green corridors and estimationof carbon sequestration) associated with the increased area ofurban green infrastructure (GI). According to the presentstudy, RTGs could provide more than 12,000 t year−1 vegeta-bles to Bologna, satisfying 77 % of the inhabitants’ require-ments. The study also advances hypotheses for the

implementation of biodiversity roofs enabling the connectionof biodiversity rich areas across and close to the city: thesewould form a network of green corridors of over 94 km lengthwith a density of about 0.67 km km−2.

Keywords Rooftop gardens . Urban food security . Greencorridors . Urban biodiversity . Urban agriculture

Introduction

Just over half the world’s population now lives in urban asopposed to rural environments. As the rate of urbanizationincreases over time, food production sites should be increas-ingly located near main consumption centers. Consequently,urban agriculture is gaining relevance all over the world(Orsini et al. 2013) and it is necessary to devise new strategiesto ensure the food supply and food security of those who livein urban environments (Tixier and de Bon 2006). The conceptof ecological citizenship (Wackernagel and Rees 1996) usesthe metaphor of ‘ecological footprint’ in which each of us isresponsible for taking up a certain amount of ecological‘space’ (both for resource use and capacity burden), expressedas a personal footprint left on the Earth. Although it is as-sumed that an equal allocation of the available space on Earthwould result in 1.8 available global hectares per person, thefootprint of the average European citizen is actually 4.9 ha,and in the USA up to 9.2 ha (Global footprint network 2005;Seyfang 2006). In Italy, there are around 42 million urbancitizens, representing 68.4 % of the total population (DESA-UN 2012). Many of these citizens are already trying to takeback some unused and abandoned areas and convert them intogreen spaces (Saldivar-Tanaka and Krasny 2004; Tei et al.

F. Orsini (*) :D. Gasperi : L. Marchetti : S. Draghetti :G. Bazzocchi :G. GianquintoDIPSA, University of Bologna, Bologna, Italye-mail: [email protected]

D. Gasperi : L. Marchetti : C. PioveneBiodiverCity, Bologna, Italy

S. RamazzottiFaculty of Bioscience and Technologies for Food Agriculture andEnvironment, University of Teramo, Teramo, Italy

Food Sec.DOI 10.1007/s12571-014-0389-6

2010). Their functions include a range of ecosystem servicesbeneficial to people, including food supply (Braat and DeGroot 2012; La Greca et al. 2011; Jim 2004). Throughoutthe city area, urban green spaces can be linked to one another,forming a network of Green Infrastructures (GIs) (Mahmoudand Mohammed 2012). Urban GIs have a clear role in defin-ing the city ecosystem (Bolund and Hunhammar 1999),whose complexity (and consequently stability/resilience)stands to be improved by urban agriculture. A range of studieshave addressed the role played by urban vegetable gardens inimproving human well-being through the provision of bothecosystem services and food supply to the city dwellers (Ma-tsuo 1995; Brown and Jameton 2000; McClintock 2010;Orsini et al. 2013). Urban gardens are found across cities ina range of different systems such as plots on public landassigned to individuals or families, community gardens real-ized in abandoned and/or vacant areas and individual orcommon gardens in yards and balconies or even on the roof-tops of buildings (RoofTop Gardens, RTGs). The possiblegreen cover of most of the empty areas of a city could be anew ecological frontier, and could become a reality in manycities (Peck 2003; Kaethler 2006; Grewal and Grewal 2012).GIs may reduce a city’s Ecological Footprint (EF) by reduc-tion of pollution and noise, the absorption of CO2 emissionsand the control of the Urban Heat Island (UHI) effect byshading. (Wackernagel and Rees 1996; Malcevschi et al.1996; Shin and Lee 2005; Wilby 2003). Thus, RTGs canreduce the expense of heating and cooling and at the sametime improve urban air quality (Peck et al. 1999). Further-more, RTGs, while being aesthetically appealing, can contrib-ute to biodiversity in the urban environment, achieve moresustainable conditions, including those necessary for the pro-duction of food and improve the overall quality of urban life(Bennett 2003; Miller 2005; Maas et al. 2006; Khandaker2004; Sanyé-Mengual et al. 2013). Urban GIs may contributeto the restoration, preservation and increase of functionalbiodiversity, with the creation of green corridors that allowsome species, especially the less mobile ones, to improve theircapacity of dispersion, thus limiting the negative impacts offragmentation (Vergnes et al. 2012). These corridors consist ofa system of hubs and links, where hubs are ‘destinations forthe wildlife and ecological processes moving to or throughthem’ and links are ‘connections tying the system together andenabling GI networks to work’ (Uslu and Shakouri 2013).

The contributions of urban horticulture to city food supplyhave been estimated in a number of cities across the world. InDar es Salaam (Tanzania), urban agriculture provides the citywith about 100,000 t year−1 of fresh food (Ratta and Nasr1996) and in Shanghai, a municipal programme promotingurban agriculture enabled cereal supplies of about 2,000,000 tyear−1 (Yi-Zhang and Zhangen 2000). In Toronto (Canada),Peck (2003) found that from 650,000 m2 of “greened” roof-tops growing vegetable crops, a yield of 4.7 million kg of

produce per year could be generated. Not surprisingly,Kaethler (2006) states that in Vancouver (Canada), it is easyto find RTGs producing food above supermarkets, restaurantsand social housing. Also in Cleveland (Ohio, USA), a studycomparing different systems for producing food in urban areasshowed that hydroponic RTGs can produce an average of19.5 kg m−2 year−1 against 1.3 kg m−2 year−1 found in con-ventional urban gardens (Grewal and Grewal 2012). In thepresent study, the city of Bologna is taken as an example forestimating how the green covering of flat roof surfaces in thecity could provide nutritional, ecological and economic ben-efits. In particular, the potential yield of fresh vegetables,mainly from simple soilless production systems in RTGs, isanalyzed and the percentage of self-reliance for food produc-tion, if all identified flat roofs were converted into RTGs, isestimated. Moreover, as these newly created GIs could beintegrated into a network of green corridors, possible benefitsfor urban biodiversity are explored. Bologna has always beenat the forefront in Italy of urban green management, especiallywith regard to urban agriculture and horticulture, and, in 2010,the city was the first to test RTGs on public housing buildings.The present manuscript describes the first three years ofexperimentation and advances ideas for future strategies toimplement new, sustainable and greener urban environments.

Materials and methods

Cultivation trials to test plant productivity

Experiments were performed on the 10th floor rooftops of twopublic housing buildings in Bologna, where community gar-dens were installed within the project GreenHousing (whosepartners were the Alma Mater Studiorum - University ofBologna, the city Council and the non-profit bodyBiodiverCity). The trials evaluated the productivity of differ-ent growing systems on the flat roofs. Species monitoredbetween April 2012 and January, 2014 were lettuce, blackcabbage (non-headed cabbage), chicory, tomato, eggplant,chili pepper, melon and watermelon. The growing systems,illustrated in Fig. 1, were a modified Nutrient Film Technique(NFT), realized on PVC pipes, a floating system (plantsgrowing on polystyrene panels floating over a nutrient solu-tion in a tank) and a solid substrate cultivation, realized inwooden containers (1.2 m length, 1.0 m width, 0.24 m3 vol-ume) made from recycled pallets and filled with commercialsoil and compost. Nutrients were continuously supplied as anutrient solution for NFT and the floating system (composi-tion: N 19 mM; P2O5 0.3 mM; K2O 2.8 mM; SO3 3.7 mM;Mg 0.6 mM + micronutrients). In the substrate cultivationsystem, 30 g m−2 of granular fertilizer were supplied onceper year, consisting of Nitrophoska NPK in the proportions15-5-20 + 2 MgO + 20 SO3 + microelements. In each

F. Orsini et al.

experiment, measures were performed on at least 9 plants pertreatment. In the substrate and floating system, about 35 % ofrooftop space was taken up with non-productive matter suchas walking and working spaces and previously existing struc-tures. Therefore productivity data from these systems wereadjusted accordingly. On the other hand, no spatial correctionswere needed for the NFT system, as this was hung fromrooftop railings. Briefly, the experimental design was asfollows:

– Lettuce (Lactuca sativa L.): three experiments were con-ducted on lettuce cvs. Canasta, Gentilina and Batavia).Seedlings (20 day-old) were transplanted on July 11,2012 (exp. #1), June 28, 2013 (exp. #2) and September24, 2013 (exp. #3). Experiments addressed the compari-son of the productivity in three growing systems (modi-fied NFT, floating and substrate cultivation), and seasonalvariation. Due to the differences in growing systemstypologies and nutrient supply and according to previousliterature, planting densities ranged from 9 plants m−2

(substrate) to 24 plants m−2 (modified NFT) and 42 plantsm−2 (floating).

– Black cabbage (Brassica oleracea Acephala Group): oneexperiment was conducted on black cabbage (cv. Ricciotoscano). Seedlings (20 day-old) were transplanted onOctober 18, 2013 to substrate (9 plants m−2).

– Chicory (Cichorium intybus L.): one experiment wasconducted on radicchio (cv. Treviso precoce). Seedlings(20 day-old) were transplanted on October 18, 2013 (exp.#1), into modified NFT (24 plant m−2) substrate (9 plantsm−2) and floating system (42 plants m−2).

– Tomato (Solanum lycopersicum L.): two experimentswere conducted on plum tomato (cv. San Marzano) andbeefsteak tomato (cv. Caramba). Seedlings (40 day-old)

were transplanted into substrate cultivation systems onApril 26, 2012 (exp. #1) and May 15, 2013 (exp. #2).Planting density was 9 plants m−2.

– Eggplant (Solanum melongena L.): one experiment wasconducted on eggplant (long slender shape, cv. Nilo F1).Seedlings (40 day-old) were transplanted into the sub-strate cultivation system on May 16, 2012 at a plantingdensity of 3.6 plants m−2.

– Chili pepper (Capsicum annum L.): one experiment wasconducted on green chili pepper (cv. Cayenna F1), Seed-lings (40 day-old) were transplanted into the substratecultivation system on May 16, 2012. Planting densitywas 5.5 plants m−2.

– Cantaloupe (Cucumis melo L.): one experiment was con-ducted on cantaloupe (cv. Honeymoon). Seedlings(40 day-old) were transplanted into the substrate cultiva-tion system on April 27, 2012 at a planting density of 2plants m−2.

– Watermelon (Citrullus lanatus Thumb.): one experimentwas conducted on watermelon (cv. Sugar belle). Seed-lings (40 day-old) were transplanted into the substratecultivation system on May 16, 2012 at a planting densityof 2.8 plants m−2.

Identification of flat roofs and terraces across the city

The area covered by all flat roofs and roof-terraces of the citywas quantified in order to detect the potential surface area thatcould be converted into RTGs. First, Google™ Earth was usedto identify all flat roofs. Vector boundaries were used to definethe Bologna municipality and flat roofs were identified andlabeled. By direct comparison on AutoCAD®, all surfaces

Fig. 1 Growing systems used inthe experiments (a, b modifiedNFT; c floating system; dsubstrate wooden container )

Exploring the potential productivity of rooftop gardens

were recognized in the CTC (Carta Tecnica Comunale, Citytechnical map) of Bologna. To simplify the procedure, theurban area was divided into uniform sections and in each ofthem the roof area was quantified. Finally, the total roof areaof Bologna (in ha) was determined and a complete map wasobtained.

Quantification of total food requirements of the city

The total food requirement of inhabitants of the Municipalityof Bologna was calculated, based on INRAN nutritional data(Leclercq et al. 2009). Consumption data of fresh vegetablesfound in the INRAN survey were extracted, and classifiedaccording to age and sex of the Bologna city population.

Creation of urban green corridors: GreenSpots and GreenNest

A network of green corridors was designed to connect threepreviously existing biodiversity reservoirs (GreenNests, iden-tified as the two EUHabitat Natura 2000 sites, namely Golenadel Lippo SIC-ZPS I T4050018 and Boschi di San Luca SIC-ZPS IT4050029 and the biggest urban park, namely GiardiniMargherita) through the network of newly implementedRTGs. The aim was to define a network across the city,enabling the beneficial fauna (pollinators, entomophagousspecies and pest parasitoids) to surmount urban physical bar-riers and spread throughout the city (Shrewsbury and Leather2012). Potential hotspots (RTGs located within forage flyingdistance) were identified and classified as GreenSpots. The

main features and locations for both GreenNests andGreenSpots are described and discussed within themanuscript.

Evaluation of ecosystem services provided by RTGs

Based on the available literature, other ecosystem servicesassociated with the implementation of RTGs were estimatedand described.

Results and discussion

Potential productivity of a RTG in Bologna

The experiments conducted in the pilot RTGs fromApril 2012to January, 2014 enabled the definition of potential yield ofspecific vegetable crops (Table 1). Yields varied dramaticallyacross cultivated species (mean production of 45.0, 5.6, 9.0,143.0, 106.5, 51.3, 37.6 and 59.5 g m−2 d−1 respectively forlettuce [mean of eight cultivars], black cabbage, chicory[mean of three cultivars], tomato [mean of two cultivars],eggplant, chili pepper, melon and watermelon) and growingsystem (e.g. yield of Canasta lettuce was 40.9, 29.5 and 34.1 gm−2 d−1 when cultivated in autumn on the floating system,NFT and substrate, respectively; Table 1). Furthermore, sea-sonal variation in daily productivity was observed (Fig. 2a),with greatest variability when plants were grown on substrate

Table 1 Crop yields in theexperimental trials

DAT Days After Transplanting,Wi Winter, Sp Spring, Su Sum-mer, Au Autumn. Yield expressedas kg m−2 . Daily productivityexpressed as g m−2 d−1

Crop Cultivar Season System DAT Yield Dailyproductivity

Lettuce Batavia Su Floating 21 2.5 119.0

Gentilina Su NFT 21 1.1 52.4

Gentilina Su Floating 25 1.3 52.0

Gentilina Su NFT 62 1.5 24.2

Canasta Au Floating 44 1.8 40.9

Canasta Au NFT 44 1.3 29.5

Canasta Au Substrate 44 1.5 34.1

Canasta Au-Wi Substrate 62 0.5 8.1

Black cabbage Riccio toscano Au-Wi Substrate 89 0.5 5.6

Chicory Treviso Au, Wi Floating 83 1.5 18.1

Treviso Au, Wi NFT 62 0.1 1.6

Treviso Au, Wi Substrate 83 0.6 7.2

Tomato San Marzano Sp, Su Substrate 99 13.4 135.4

Caramba Sp, Su Substrate 95 14.3 150.5

Eggplant Nilo F1 Sp, Su Substrate 77 8.2 106.5

Chili pepper Cayenna F1 Sp, Su Substrate 80 4.1 51.3

Melon Honeymoon Sp, Su Substrate 101 3.8 37.6

Watermelon Sugar belle Sp, Su Substrate 82 4.8 58.5

F. Orsini et al.

(yield ranging from 10 to 98 g m−2 d−1 respectively in winter,November to January, and spring-summer, April to July).Production peaks were also experienced in the floating systemin summer (mean productivity of 70 g m−2 d−1 in July-Augustas compared to a mean of 25 g m−2 d−1 in the remainingmonths). Less seasonal variability was observed in the pro-ductivity of plants grown on NFT (13 to 40 g m−2 d−1 inJanuary and July, respectively; Fig. 2a). Across the year, meanproductivity of the growing systems used was 25, 52 and 33 gm−2 d−1 for NFT, substrate and the floating system, respec-tively, resulting in a yearly yield of 9.2, 18.9 and 12.0 kg m−2,respectively (Fig. 2b). These yields were obtained by com-bining cultivation of lettuce (year round), chicory andblack cabbage (October to April) tomato and cantaloupe(April to August) and eggplant, chili pepper and watermel-on (May to August).

Based on the productivity results, the optimal rooftop gar-den was designed (Fig. 3), considering a range of elements.First, the optimal garden should ensure that seasonal variationin productivity would be reduced to a minimum in order tobetter satisfy food requirements throughout the year. Second-ly, specific features of each of the growing systems to be usedshould be taken into account: substrate growing systems arenecessary for cultivation of fruit crops. They may also beappropriate for leafy vegetables, although with generally low-er yield compared with NFTand floating systems, mainly as aconsequence of the reduced/delayed water/nutrient availabil-ity, which translates into lower planting densities (Savvas et al.2013). Both floating and modified NFT systems could beefficiently used for growing leafy vegetables, although highertemperatures could result in low oxygenation of nutrient so-lution (Savvas et al. 2013) and consequent reduced plantgrowth and eventual death. The floating system alwaysyielded better than the NFT system. However, due to its linearshape and being hung on rooftop railings, the NFT systemcould allow vegetable production where surface area is limit-ed. Based on these considerations, the first step toward iden-tification of the optimal garden design was the creation of anNFT system along the railings surrounding the rooftop garden(about 5 m2 growing surface in a rooftop of 216m2). Substrateand floating cultivation systems were then placed on theremaining surface. Mean daily production was calculated ona yearly basis and across the different seasons (winter, spring,summer and autumn), and related to changing ratios betweensubstrate and floating cultivation systems (Fig. 3a and b).Optimal ratio was defined as the one that would maximizeyield and concurrently reduce variation of seasonal yield (asexpressed by the standard error across seasonal yield (Fig. 3b).A ratio of 43:57 (substrate:floating systems) would allow themaximal yield (41.7 g m−2 d−1 or 15.2 kg m−2 year−1) andminimize seasonal variation in monthly productivity (standarderror of 23 g m−2 d−1). These results seem to be realistic asprevious studies of a similar nature reported production of7 kg m−2 year−1 (Peck 2003), 18 kg m−2 year−1 (Altieri et al.1999) and up to 50 kgm−2 year−1 (Drescher 2004). The resultswere used to design an optimal rooftop garden, given a surfacearea of 216 m2. This consisted of 155 growing structures (67substrate and 88 floating system, Fig. 3c) which would enablethe annual production of 3,283.2 kg year−1.

Vegetable requirement of the city

Calculation of the fresh vegetable requirement of the citywas performed by multiplying consumption data accord-ing to age and sex by the city population (Leclercq et al.2009; USP-BO 2013; Table 2). The overall vegetablerequirement of Bologna was calculated to be about44,300 kg d−1 (=16,169 t year−1). Greatest consumptionwas observed in male and female adults (aged between 18

Fig. 2 Daily (a, g m−2 d−1) and cumulated (b, kg m−2) yield of thesimplified soilless systems (Substrate, Floating and NFT) used in theexperiments according to crops grown in each season. Data calculated onmean values of tested crops in each growing system. Vertical barsindicate standard errors

Exploring the potential productivity of rooftop gardens

and 65 years), whose consumption (10,362 t year−1) rep-resented about 64 % of the city’s fresh vegetable require-ments. This volume of fresh food has environmental im-plications for both production and post-harvest manage-ment. In a comparative study that considered the environ-mental impact of onion production and post-harvest

management in both UK and New Zealand, the latter’spost-harvest (grading, storage and shipping) was respon-sible for 68 to 75 % of the total carbon emission (kg CO2

t−1 FW; Saunders et al. 2006). Traditional systems forvegetable production and distribution in the UK were alsoreported to result in 0.10 to 0.80 kg CO2 per kg of fresh

Fig. 3 Optimum ratio betweenfloating system and substratecultivation system. Mean dailyproductivity (g m−2 d−1) withinseasons (a, winter, grey; spring,green; summer, red; and autumn,orange) and across the year (b,blue symbols). Vertical barsindicate standard errors of meanyearly productivity. Dottedvertical bar represents optimumratio (43:57 for substrate: floatingsystem) enabling satisfactoryyield and reduced seasonalfluctuations in productivity. cgraphical representation of thegarden to be implemented in thiscase study rooftop according tooptimum growing system ratios

Table 2 Supply requirements forfresh vegetables of Bologna in-habitants (based on consumptiondata)

Daily intake expressed as Kg d−1

person−1 . Total daily requirementexpressed as kg d−1

Category Age Daily intake Population Total dailyrequirement

Male infant 0–3 0.019 7,970 147.45

Female infant 0–3 0.019 7,449 137.81

Male children 3–9 0.060 7,574 457.47

Female children 3–9 0.060 6,846 413.50

Male teenager 9–18 0.091 13,843 1,254.18

Female teenager 9–18 0.085 13,044 1,112.65

Male adult 18–65 0.128 112,049 14,308.66

Female adult 18–65 0.121 116,761 14,081.38

Male elderly ≥65 0.131 39,703 5,189.18

Female elderly ≥65 0.120 60,090 7,198.78

Total 44,301.05

F. Orsini et al.

produce (Milà i Canal et al. 2008). Other studies associ-ated with tomato cultivation reported similar values (0.14to 0.81 kg CO2 kg−1; Antón 2004; Roy et al. 2008).Another study reported that packaging contributed about45 % of the total carbon emission associated withtraditional tomato cultivation. RTGs could limit CO2

production to about a third (0.26 vs 0.70 kg CO2

kg−1, respectively for rooftop greenhouses and conven-tional rural greenhouse cultivation; Sanyé-Mengual et al.2013). The fresh vegetable market in northern Italymainly relies on national products (mostly from Sicily,Puglia and Emilia-Romagna regions), although net im-port also exists from other European and Mediterraneancountries (De Luca and Dever 2011; Perito 2006).Imported tomatoes (about 80,000 t year−1) are mainlyfrom other European countries (mostly Spain and Hol-land, 32,000 and 22,000 t year−1, respectively). Freshvegetables are also imported from non-European coun-tries. Supermarket chains, responsible for about 45 to50 % of the vegetables currently sold in Italian cities,import between 1 and 5 % of their vegetables e.g.tomatoes, beans, eggplants, zucchini and cantaloupefrom other Mediterranean Countries, mainly Egypt andMorocco (Perito 2006). RTGs could therefore dramati-cally reduce the ecological footprint of fresh vegetablesby reducing transport requirements, re-using packaging,and the reduction of product storage between harvestand consumption (Sanyé-Mengual et al. 2013).

Estimation of the city’s flat roof surfaces and potentialproductivity

There are about 3,500 flat rooftops in Bologna with a totalsurface area of about 82 ha (Fig. 4 and Table 3). Based on theproduction results of the current case study (41.7 g vegetablesm−2 d−1), the entire rooftop surface of Bologna could produceabout 12,505 t vegetables year−1, which is 77 % of thecalculated vegetable requirement of the city (16,169, t year−1;Table 3). Thus, RTGs could provide an important contributionto food availability in cities, as well as being instruments forsocialization and community building.

Creation of a network of green corridors

In rural environments, beneficial insects benefit agriculturalproduction when their habitats e.g. green field edges and bee-hives are within certain distances from crops. In urban GImanagement, recognition of the value of biodiversity has beengrowing in recent years, with the main aim of reducing pestincidence in both vegetable and ornamental gardens (Buczackiand Harris 2005). Even so, evidence for the benefits associatedwith the creation of urban green corridors is still missing. TheEU Habitat Policy identifies GIs as the most crucial element forpromoting ecological connections of the wild flora and fauna(EU-Environment 2014). In the present study, the first steptowards the identification of a strategy to improve urban biodi-versity was considered to be valorisation of the city’s

Fig. 4 Procedure for flat rooftopsurface detection. Identification offlat rooftops on GoogleEarth® (a,b), as represented on urban citymaps (c) and calculation ofavailable surfaces throughAutocad® (d)

Exploring the potential productivity of rooftop gardens

biodiversity reservoirs. GreenNests e.g. greenhouses and indoorstructures should be increased to house and increase the popu-lations of appropriate fauna, which could be dispersedwithin thecity. Furthermore, RTGs can be used to increase urban biodi-versity, for example by becoming hotspots (GreenSpots) of anetwork of GIs. In order to enable beneficial fauna to takeadvantage of the GreenSpots, RTGs should be provided withshelters, wild flowers for pollen and nectar as well as plants withalternative preys for predators (Burgio et al. 2004; Gurr et al.2012). In the present study, a network of green corridors wasdesigned to connect flat rooftops located within 500 m of eachother (Fig. 5). Such a distance is appropriate as most commonApoidea pollinators (with only a few exceptions) have a flightforaging distance of between 750 and 1,500 m (Gathmann andTscharntke 2002; Osborne et al. 2008; Zurbuchen et al. 2010).Moreover, when it comes to beneficial predators e.g. ladybirds,flying distances are much greater, as these species may rely onalternative sources of food (Lundgren 2009).

Accordingly, the three biodiversity reservoirs (GreenNestsFig. 5) would be connected by a network of green corridors witha total length of about 94 km within the city boundaries. Theseflying routes would constitute a substantial element for ensuringlong-term persistence and resilience of urban biodiversity.Green corridor density was defined as the ratio between thelinear distance covered by green corridors (94 Km) and the citysurface area, (140.73 km2), giving a value of 0.67 km km−2

(Zhang and Wang 2006; Comune di Bologna 2014; Table 3).

Other ecosystem services associated with increased urbanGIs

Given that more than half of the world’s population live inurban areas (Orsini et al. 2013), the world’s cities are respon-sible for the majority of carbon dioxide (CO2) in the atmo-sphere (Girardet 1999). Despite urbanization being a major

global driver of change in land-use, there have been fewattempts to quantify provision of ecosystem services for cities.One service that is an increasingly important feature for mit-igation of climate change is the biological carbon storageassociated with urban GIs. Indeed, given that urban gardensmay exhibit higher levels of vegetation productivity than thefarmed areas they replace (Zhao et al. 2007), the role of RTGsin storing carbon should not be overlooked. In a recent study(Davies et al. 2011), it was estimated that domestic gardenswould enable storage of about 0.76 kg C m−2. Based on these

Table 3 Potential RTG vegetable production in Bologna. Available flatsurfaces (number and hectares), potential productivity and extent of cityrequirements satisfied if those surfaces were converted into RTGs

Element Value

Flat rooftops 3,500

Flat area 82 ha

Potential rooftop yield 41.7 g m−2 d−1

Potential vegetable daily production 34,233 kg d−1

Potential vegetable yearly production 12,505 t year−1

Urban vegetable requirements 16,169 t year−1

Contribution to city needs 77 %

Green corridors 94 km

Green corridor density 0.67 km km−2

Potential carbon storage 624 t CO2

Fig. 5 Localization of three GreenNests (1, Bosco di San Luca SIC-ZPSIT4050029, 2, Golena del Lippo SIC-ZPS I T4050018, 3 GiardiniMargherita) and flat surfaces identified for RTG implementation (blackspots) (a). Green corridors across the city of Bologna connecting RTGswithin 500 m distance of each other. (b)

F. Orsini et al.

figures, it was possible to estimate that turning Bologna’s flatroof surfaces into RTGs would enable the capture of 624.42 tCO2 (Table 3).

Beyond the benefits associated with food production andthe natural environment, community gardening is claimed toimprove human well-being (Okvat and Zautra 2011). Togeth-er with the urbanization process, there has been a trend in thequest for the green experience: throughout history, both gar-dening and more passive forms of contact with nature (e.g.taking a walk in a garden) have been recognised as havingmental health benefits (Davis 1998). Although limited scien-tific reports are available to date on the therapeutic role ofcommunity gardening, the gardening-related benefits in re-ducing psychological disorders e.g. against dementia (Simonset al. 2006), enabling stress recovery (Kingsley et al. 2009), orfostering cardiac rehabilitation (Wichrowski et al. 2005) arewell known. It is also true that certain features of city neigh-borhoods (e.g. crime rate, levels of noise, crowding) arecorrelated with a lack of neighborhood social ties (Kuo andSullivan 2001). When vegetable gardens become catalysts ofcommunity building in cities, the implications for the well-being of the urban population may be described within theconcept of socio-ecological space (Okvat and Zautra 2011).For instance, community gardens can contribute to the crea-tion of resilient urban neighborhoods and facilitate a city’srecovery when faced with a sudden crisis (e.g. natural disas-ters, conflicts or economic downturns; Tidball and Krasy2007). As the concept of resilience is associatedwith diversity,it may be well described by a RTG grouping together theinhabitants of a building (being an inter-generational andinter-ethnical blend of people), which inevitably will grow arange of different plants (Fraser and Kenney 2000), yieldingconsiderable biodiversity within the garden. Under these cir-cumstances each of the proposed RTGs may group residentstogether into a dense network (Glover 2003), decreasing iso-lation through sharing of gardening inputs and knowledge(Wakefield et al. 2007) and promoting a participatory ap-proach to community development (Saldivar-Tanaka andKrasny 2004). Furthermore, a RTG may promote resiliencethrough a series of social features (communication, informa-tion-sharing, deliberate co-learning and produce exchange)and ecological phenomena (reducing the environmental im-pact of food production and promoting self-sufficiency). Fi-nally, RTGs may play an important role in offering aestheticenjoyment and increased property values (Noss 1987).

Conclusions

The present manuscript explores the multifaceted benefitsassociated with the implementation of RTGs in Bologna.Through experimental trials on a pilot RTG, potential vegeta-ble yields were defined over a three year period, enabling

determination of daily productivity per unit surface area(41.7 g m−2 d−1). Furthermore, through mapping and quanti-fying urban flat roof surfaces, it was determined that the areaof RTGs in Bologna was 82 ha, potentially enabling theannual production of 12,495 t vegetables year−1, 77 % of theurban vegetable requirement. As well as the evident contribu-tion to city food security, such newly planted gardens wouldallow the interconnection of centres of biodiversity in the cityby creating a network of green corridors with a total length of94 km and a density of 0.67 km km−2. Finally, based onpotential carbon storage estimates, these RTGs would resultin the annual capture of about 624 t CO2.

Acknowledgments The present research was partially funded with thesupport of EU projects HORTIS (Horticulture in Towns for Inclusion andSocialisation) and HYBRID PARKS and with the support of BolognaCity Council and the Emilia Romagna Region. This publication reflectssolely the views of the authors, who are not responsible for any use towhich the information contained therein is put.

References

Altieri, M. A., Compagnoni, N., Cañizares, K., Murphy, C., Rosset, P.,Bourque, M., & Nicholls, C. I. (1999). The greening of the “barri-os”: Urban agriculture for food security in Cuba. Agriculture andHuman Values, 16, 131–140.

Antón, A. (2004). The use of life cycle assessment methodology toenvironmentally assess Mediterranean crops in greenhouses. PhDdissertation, Universitat Politecnica de Catalunya, Barcelona.

Bennett, A. F. (2003). Linkages in the landscape: The role of corridorsand connectivity in wildlife conservation. Gland: InternationalUnion for Conservation of Nature and Natural Resources.

Bolund, P., & Hunhammar, S. (1999). Ecosystem services in urban areas.Ecological Economics, 29, 293–301.

Braat, L. C., & De Groot, R. (2012). The ecosystem services agenda:Bridging the worlds of natural science and economics, conservationand development, and public and private policy. EcosystemServices, 1, 4–15.

Brown, K. H., & Jameton, A. L. (2000). Public health implications ofurban agriculture. Journal of Public Health Policy, 21, 20–39.

Buczacki, S., & Harris, K. (2005). Pests, diseases & disorders of gardenplants. New York: HarperCollins.

Burgio, G., Ferrari, R., Pozzati, M., & Boriani, L. (2004). The role ofecological compensation areas on predator populations: An analysison biodiversity and phenology of Coccinellidae (Coleoptera) onnon-crop plants within hedgerows in Northern Italy. Bulletin ofInsectology, 57, 1–10.

Davies, Z. G., Edmondson, J. L., Heinemeyer, A., Leake, J. R., &Gaston,K. J. (2011). Mapping an urban ecosystem service: Quantifyingabove‐ground carbon storage at a city‐wide scale. Journal ofApplied Ecology, 48, 1125–1134.

Davis, S. (1998). Development of the profession of horticultural therapy.In S. P. Simson & M. C. Straus (Eds.), Horticulture as therapy:Principles and practice (pp. 3–18). New York: The Haworth Press.

De Luca, A., &Dever, J. (2011). Italy tomatoes and products report 2011.Rome: USDA.

DESA-UN (2012). World Urbanization Prospect. http://esa.un.org/unup/CD-ROM/Urban–rural-Population.htm. Accessed 9 April 2013.

Comune di Bologna (2014). Iperbole. Bologna Welcome. Sito turisticoUfficiale. http://www.bolognawelcome.com/guida-turistica/indice-

Exploring the potential productivity of rooftop gardens

completo/params/Ambiente_2/Famiglia_2.01/ref/Localit%C3%A0.Accessed 4 March 2014.

Drescher, A. W. (2004). Food for the cities: Urban agriculture in devel-oping countries. Acta Horticulturae, 643, 227–231.

EU-Environment. (2014). Communication from the commission to theEuropean parliament, the council, the european economic andsocial committee and the committee of the regions GreenInfrastructure (GI) — Enhancing Europe’s Natural Capital COM/2013/0249 final. Bruxelles: European Commission.

Fraser, E. G. G., & Kenney, W. A. (2000). Cultural background andlandscape history as factors affecting perceptions of the urban forest.Journal of Arboriculture, 26, 106–113.

Gathmann, A., & Tscharntke, T. (2002). Foraging ranges of solitary bees.Journal of Animal Ecology, 71, 757–764.

Girardet, H. (1999). Toward urban sustainability. In United NationsEnvironment Programme’s Cultural and spiritual values ofbiodiversity (pp. 255–258). Nairobi: Intermediate TechnologyPublications.

Global footprint network (2005). http://www.ecofoot.net. Accessed 4March 2014.

Glover, T. D. (2003). The story of the Queen Anne memorial garden:Resisting a dominant cultural narrative. Journal of LeisureResearch, 35, 190–212.

Grewal, S. S., & Grewal, P. S. (2012). Can cities become self-reliant infood? Cities, 29, 1–11.

Gurr, G. M., Wratten, S. D., Snyder, W. E., & Read, D. M. Y. (2012).Biodiversity and insect pests: Key issues for sustainablemanagement. Chichester: Wiley.

Jim, C. Y. (2004). Green-space preservation and allocation for sustainablegreening of compact cities. Cities, 21, 311–320.

Kaethler, T. M. (2006). Growing space: the potential for urban agriculturein the city of Vancouver. School of community and regional plan-ning. University of British Columbia. bitsandbytes.ca/sites/default/files/Growing_Space_Rpt.pdf. Accessed 4 March 2014.

Khandaker, M. S. I. (2004). Rooftop gardening as a strategy of urbanagriculture for food security: The case of Dhaka City, Bangladesh.Acta Horticulturae, 643, 241–247.

Kingsley, J., Townsend, M., & Henderson-Wilson, C. (2009). Cultivatinghealth and well-being: Members’ perceptions of the health benefitsof a Port Melbourne community garden. Leisure Studies, 28, 207–219.

Kuo, F. E., & Sullivan, W. C. (2001). Environment and crime in the innercity: Does vegetation reduce crime? Environment and Behavior, 33,343–367.

La Greca, P., La Rosa, D., Martinico, F., & Privitera, R. (2011).Agricultural and green infrastructures: The role of non-urbanisedareas for eco-sustainable planning in a metropolitan region.Environmental Pollution, 159, 2193–2202.

Leclercq, C., Arcella, D., Piccinelli, R., Sette, S., Le Donne, C., & Turrini,A. (2009). The Italian national food consumption survey INRAN-SCAI 2005–2006: Main results in terms of food consumption.Public Health Nutrition, 12, 2504–2532.

Lundgren, J. G. (2009). Nutritional aspects of non-prey foods in the lifehistories of predaceous Coccinellidae. Biological Control, 51, 294–305.

Maas, J., Verheij, R. A., Groenewegen, P. P., De Vries, S., & Spreeuwenberg,P. (2006). Green space, urbanity, and health: How strong is the relation?Journal of Epidemiol Community Health, 60, 587–592.

Mahmoud, N., & Mohammed, G. (2012). Green infrastructure connec-tivity within social sustainability: Case studies around the world.Canadian Journal on Computing inMathematics, Natural Sciences,Engineering and Medicine, 3, 225–232.

Malcevschi, S., Bisogni, L., & Gariboldi, A. (1996). Reti ecologiche edinterventi di miglioramento ambientale. Milano: Il Verde Editoriale.

Matsuo, E. (1995). Horticulture helps us to live as human beings:Providing balance and harmony in our behavior and thought andlife worth living. Acta Horticulturae, 391, 19–30.

McClintock, N. (2010). Why farm the city? Theorizing urban agriculturethrough a lens of metabolic rift. Cambridge Journal of Regions,Economy and Society, 3, 191–207.

Milà i Canal, L. L., Muñoz, I., Hospido, A., Plassmann, K., & McLaren,S. (2008). Life cycle assessment (LCA) of domestic vs. importedvegetables. Case studies on Broccoli, salad crops and green beans.Surrey. UK: University of Surrey, CES.

Miller, J. R. (2005). Biodiversity conservation and the extinction ofexperience. Trends in Ecology and Evolution, 20, 430–434.

Noss, R. F. (1987). From plant communities to landscapes in conservationinventories: A look at The Nature Conservancy (USA). BiologicalConservation, 41, 11–37.

Okvat, H. A., & Zautra, A. J. (2011). Community gardening: A parsimo-nious path to individual, community, and environmental resilience.American Journal of Community Psychology, 47, 374–387.

Orsini, F., Kahane, R., Nono-Womdim, R., & Gianquinto, G. (2013).Urban agriculture in the developing world. A review. Agronomy forSustainable Development, 33, 695–720.

Osborne, J. L., Martin, A. P., Carreck, N. L., Swain, J. L., Knight, M. E.,Goulson, D., Hale, R. J., & Sanderson, R. A. (2008). Bumblebeeflight distances in relation to the forage landscape. Journal ofAnimal Ecology, 77, 406–415.

Peck, S. (2003). Towards an integrated green roof infrastructure evalua-tion for Toronto. The Green Roof Infrastructure Monitor, 5, 4–7.

Peck, S., Callaghan, C., Kuhn, M. E., & Bass, B. (1999). Greenbacksfrom green roofs: Forging a new industry in Canada. Ottawa:Canadian Mortgage and Housing Corporation.

Perito, M. A. (2006). La distribuzione moderna e il global sourcing:l’acquisto di prodotti orto-frutticoli dai Paesi Terzi delMediterraneo. Economia Agroalimentare, 3, 1–9.

Ratta, A., & Nasr, J. (1996). Urban agriculture and the African urbanfood supply system. New York: TUAN.

Roy, P., Nei, D., Okadome, H., Nakamura, N., Orikasa, T., & Shiina, T.(2008). Life cycle inventory analysis of fresh tomato distributionsystems in Japan considering the quality aspect. Journal of FoodEngineering, 86, 225–233.

Saldivar-Tanaka, L., & Krasny, M. E. (2004). Culturing communitydevelopment, neighborhood open space, and civil agricultural: Thecase of Latino community gardens in New York City. Agricultureand Human Values, 21, 399–412.

Sanyé-Mengual, E., Cerón-Palma, I., Oliver-Solà, J., Montero, J. I., &Rieradevall, J. (2013). Environmental analysis of the logistics ofagricultural products from roof top greenhouses in Mediterraneanurban areas. Journal of Science Food and Agriculture, 93, 100–109.

Saunders, C., Barber, A., & Taylor, G. (2006). Food miles - comparativeenergy/emissions performance of New Zealand’s agriculture indus-try, research report no. 285. Città: Lincoln University.

Savvas, D., Gianquinto, G., Tüzel, Y., & Gruda, N. (2013).Chapter 19. Soilless culture. In M. Quaryoti, W. Baudoin,R. Nono Womdin, C. Leonardi, A. Hanafi, & S. De Pascale(Eds.), Good agricultural practices for greenhouse vegetablecrops. Principles for Mediterranean climate areas (AGP series,Vol. 217). Rome: FAO-UN.

Seyfang, G. (2006). Ecological citizenship and sustainable consumption:Examining local organic food networks. Journal of Rural Studies,22, 383–395.

F. Orsini et al.

Shin, D. H., & Lee, K. S. (2005). Use of remote sensing and geographicalinformation system to estimate green space temperature change as aresult of urban expansion. Landscape and Ecological Engineering, 1,169–176.

Shrewsbury, P. M., & Leather, S. R. (2012). Using biodiversity for pestsuppression in urban landscapes. In G.M. Gurr, S. D.Wratten,W. E.Snyder, & D. M. Y. Read (Eds.), Biodiversity and insect pests: Keyissues for sustainable management. Chichester: Wiley. doi:10.1002/9781118231838.ch18.

Simons, L. A., Simons, J., McCallum, J., & Friedlander, Y. (2006).Lifestyle factors and risk of dementia: Dubbo study of the elderly.The Medical Journal of Australia, 184, 68–70.

Tei, F., Benincasa, P., Farneselli, M., & Caprai, M. (2010). Allotmentgardens for senior citizens in Italy: Current status and technicalproposals. Acta Horticulturae (ISHS), 639, 51–55.

Tidball, K. G., & Krasy, M. E. (2007). From risk to resilience: What rolefor community greening and civic ecology in cities? In A. E. J. Wals(Ed.), Social learning towards a sustainable world: Principles,perspectives and praxis (pp. 149–164). Wageningen: WageningenAcademic Publishers.

Tixier, P., & de Bon, H. (2006). Urban horticulture. In R. van Veenhuizen(Ed.), Cities farming for the future – Urban Agriculture for greenand productive cities (pp. 316–347). Leusden: RUAF Foundation,IDRC and IIRR.

Uslu, A., & Shakouri, N. (2013). Chapter 17: Urban landscape design andbiodiversity environmental sciences. In M. Özyavuz (Ed.),Advances in Landscape Architecture. Winchester: InTech Open.doi:10.5772/55761. ISBN 978-953-51-1167-2.

USP-BO. (2013). Popolazione residente al 31/12/2012 nei comuni dellaprovincia di Bologna per sesso ed età. Ufficio di statistica dellaProvincia di Bologna su dati delle Anagrafi comunali. Bologna:Comune di Bologna.

Vergnes, A., Le Viol, I., & Clergeau, P. (2012). Green corridors in urbanlandscapes affect the arthropod communities of domestic gardens.Biological Conservation, 145, 171–178. doi:10.1016/j.biocon.2011.11.002.

Wackernagel, M., & Rees, W. (1996). Our ecological footprint:Reducing human impact on the Earth. Philadelphia: Newsociety publisher.

Wakefield, S., Yeudall, F., Taron, C., Reynolds, J., & Skinner, A. (2007).Growing urban health: Community gardening in South- EastToronto. Health Promotion International, 22, 92–101.

Wichrowski, M., Whiteson, J., Haas, F., Mola, A., & Rey, M. J. (2005).Effects of horticultural therapy on mood and heart rate in patientsparticipating in an inpatient cardiopulmonary rehabilitation pro-gram. Journal of Cardiopulmonary Rehabilitation, 25, 270–274.

Wilby, R. L. (2003). Past and projected trends in London’s urban heatisland. Weather, 58, 251–260.

Yi-Zhang, C., & Zhangen, Z. (2000). Shanghai: Trends towardsspecialised and capital intensive urban agriculture. In N. Bakker,M. Dubbeling, S. Guendel, U. Sabel Koschella, & H. de Zeeuw(Eds.), Growing cities, growing food, urban agriculture on thepolicy agenda (pp. 467–475). Feldafing: DSE.

Zhang, L., & Wang, H. (2006). Planning an ecological network ofXiamen Island (China) using landscape metrics and network analy-sis. Landscape and Urban Planning, 78, 449–456.

Zhao, T., Brown, D. G., & Bergen, K. M. (2007). Increasing grossprimary production (GPP) in the urbanizing landscapes of south-eastern Michigan. Photogrammetric Engineering and RemoteSensing, 73, 1159–1168.

Zurbuchen, A., Landert, L., Klaiber, J., Müller, A., Hein, S., & Dorn, S.(2010). Maximum foraging ranges in solitary bees: Only few

individuals have the capability to cover long foraging distances.Biological Conservation, 143, 669–676.

Francesco Orsini Dr. Francescois a post-doctoral researcher withexperience in promotion of urbanfarming and training. He was thewinner of the young researcheraward 2010 of the Italian Societyfor Horticultural Sciences (SOI).Together with Prof. Gianquinto,Francesco Orsini coordinates ur-ban horticultural activities in theMunicipality of Bologna, promot-ing school gardens and providingtechnical assistance to urban gar-dens managed by elders and im-migrants. The group also coordi-

nates the project “GreenHousing” for the realization of a pilot roof gardenfor fruit and vegetable production in the popular buildings of Bologna. Dr.Orsini has been involved in urban horticultural projects in Peru, Brazil,Myanmar, Kenya, Kosovo, Mauritania, Ivory Coast and Burkina Faso.He has been an FAO consultant in the Ivory Coast and Cape Verde.

Daniela GasperiDaniela Gasperihas an M.Sc. in International Hor-ticulture from the University ofBologna and is currently studyingecological functions of RTGs inthe urban environment, imple-mentation of Life Cycle Analysis(LCA) and Social LCA of urbanhorticulture. Daniela Gasperi iscurrently President of the Associ-ation Biodivercity.

Livia Marchetti Livia Marchettihas an M.Sc. in International Hor-ticulture from the University ofBologna and is studying for herPh.D. in design, application andproductivity of simplified soillesscultures for urban vegetable culti-vation, as well as food securityand food safety aspects of urbanhorticulture.

Exploring the potential productivity of rooftop gardens

Chiara Piovene Chiara Piovenehas an M.Sc. in International Hor-ticulture from the University ofBologna and is studying simpli-fied soilless cultivation systemsand carrying out research on arti-ficial lighting for home vegetablecultivation. She is co-founder ofSpin-Off Bulbo, specializing inthe production of LED lightingsystems for indoor hydroponics.

Stefano Draghetti Dr. StefanoDraghetti graduated in NaturalSciences with a thesis concerningthe development of mosquitoes inthe plain of Bologna and in 2010was awarded the PhD degree inAgricultural Entomology with athesis entitled “Responses of in-sect pests and natural enemies toolfactory and visual stimuli.” Hismain topics of research and inter-est are Medical and VeterinaryEntomology, Urban Ecology, Ur-ban Horticulture and Environ-mental Educational Programs.

He worked from 1995 to 2002 in the G. Nicoli Environment AgricultureCenter (CAA) in the field of Veterinary Medical Entomology. He co-founded Eugea S.r.l. (a Bologna University spin-off working on UrbanEcology). He has been a member of Horticity S.r.l. since 2012 and isFoundingMember and former President of the Association BiodiverCity,with responsibility for the development and implementation of events,meetings and projects in Ecology, Horticulture and Biodiversity in UrbanAreas.

Solange Ramazzotti Dr. SolangeRamazzotti is a researcher in treecrops at the University of Teramo.She has an M.Sc. cum laude inAgricultural Sciences, Universityof Ancona (Italy) with a final dis-sertation on “Molecular character-ization of some local vine grapecultivars through microsatellitemarkers”. Her PhD was obtainedat the Department of Fruit Treeand Woody Plant Sciences, Uni-versity of Bologna, Italy with afinal dissertation entitled “Bio-chemical and molecular charac-

terization of the anthocyanin pathway in Sangiovese spots with differentcolour of berry skin”. She also has anM.Sc. in International Co-operation

in Rural Areas from the University of Padova. Her research experiencesare in urban garden design and implementation and conducting researchtrials in urban vineyard cultivation. Her teaching experiences are inagricultural faculties and adult and third age intensive courses.

Giovanni Bazzocchi Dr.Giovanni Bazzocchi gradu-ated in Biological Sciencescum laude in 1993 at theUniversity of Bologna witha thesis on Entomology. HisPhD is in Agricultural Ento-mology and concerned theChemica l Eco logy inTritrophic interactions inagroecosystems. He wasProfessor of General Ento-mology at the University ofModena and Reggio Emilia(2002/2003) and has carried

out research in the following fields: general and urban entomology,biological control in small and soil-less gardens, urban biodiversity,landscape entomology, chemical ecology, pheromones and semiochemi-cals. He co-founded Eugea S.r.l. (a Bologna University spin-off workingon Urban Ecology) and is a member of Horticity S.r.l. where he iscurrently head of the research and development department, and projectmanager and coordinator of HORTIS - Horticulture in Towns for Inclu-sion and Socialisation, an EU-LLP program (Horticity partner). Dr.Bazzocchi has been involved in urban horticultural projects in Brazil(University of Bologna) and Mauritania (Horticity).

Giorgio Gianquinto GiorgioGianquinto is a full professor ofHorticulture at the University ofBologna, Director of the ResearchCentre on Urban Agriculture andBiodiversity (RESCUE-AB,h t tp : / / r e scue-ab .un ibo . i t / )P r e s i d e n t o f t h e I S H Scommission on Landscape andUrban Horticulture; Convenor ofthe 2nd International Conferenceon Landscape and UrbanHorticulture; Coordinator of LLPHORTIS project 526476-LLP-1-2012-1-ITGRUNDTVIG-GMP.

He is an FAO consultant in Cape Verde, Ivory Coast and Burkina Fasoand scientific coordinator of international cooperation projects on urbancommunity farming in Brazil, Peru, Myanmar, Burkina Faso andMauritania.

F. Orsini et al.