Vegetación urbana y riego con recursos de agua no convencionales

1. Vegetación urbana y riego con recursos de agua no convencionales Environmental Horticulture / Ecophysiology Robert Savé, Carmen Biel, Felicidad de Herralde, Xavier Aranda,

2. Vulnerability of urban green spaces Already in the Book of Psalms (48.2) appeared the term "landscape" which is maintained in romantic literature of XIX century and it refers mainly to an aesthetic, geographical and to some extent dynamic bit concept (Naveh & Lieberman 1894). After appeared the concept of "landscape ecology" in which the landscape is the visual representation of an intricate network of biodiversity (Zonneveld 1989, Sanderson & Harris 2000). Recently, it was developed the term "Restoration of the landscape," which addresses the need to put the landscape back to its original level of diversity after this has undergone some type of disturbance, which can be done in a natural manner or with the help of techniques and systems (Harker et al. 1999; KlopateK & Gardner 1999).

3. Vulnerability of urban green spaces Landscape representation as a biodiversity mesh (Zonneveld 1989). Similarly than in others ecosystems, a city is a complex ecosystem and consequently it must be studied according ecophysiological science and tools (Savé 2008)

4. Vulnerability of urban green spaces As in this Symposium, ecophysiology is placed after other topics. Thus, designers of cities and landscapes appear and perform their work before the agricultural engineers, gardeners, ecologists, physiologists. This promotes imbalances and environmental problems for management of green in cities.

5. Vulnerability of urban green spaces An urban area is a space with high population density which develops new, major and complex structures in comparison to the areas surrounding it. Urban areas may be cities, towns or conurbations. In order to develop these structures and to maintain population and its activity, metabolism of urban areas need a lot of external sources of energy and nutrients (water, food, materials ...) and produce heat, waste garbage, sewage and pollution, which are some major problems for urban areas, and the close and far areas of it. This metabolism develops specific microclimates, which are attributable to the large clustering of heat absorbent surfaces that heat up in sunlight, the important modifications in hydrological cycle due to drastic soil reduction and that channel rainwater into underground ducts.

6. Vulnerability of urban green spaces This metabolism promotes major environmental changes in the urban areas. From XIX century, hygienist movement developed a new way of life of the citizens by means of gardens and landscape design. This process has been increased in the last decades in together with the development of social economy and social sensibility. As a result of this process, urbanism and landscaping have acquired a very important role in the quality of life of the people.

7. Vulnerability of urban green spaces

8. Vulnerability of urban green spaces Barcelona is an old city placed on Mediterranean sea coastal into Iberic Peninsula. It’s under Mediterranean climate characteristics. It has about 60 different types of urban parks, historical, thematic, forest, big, small ,...) located throughout the city. Climatic diagram of Barcelona city

9. Vulnerability of urban green spaces .

10. Vulnerability of urban green spaces

11. Vulnerability of urban green spaces • The potential climate change attributable to global change, can increase local and general temperature (IPCC, 2007). These small changes in temperature may have great influence in atmospheric carbon balance (Valentini et al 2000). • This increase will not be the same around the world (IPCC 2004); it seems it will be particularly important in the Mediterranean Basin (Pinyol et al 1998). Thus, according to the most pessimistic predictions, temperature may increase up to 4ºC and rainfall may have a 10 to 40% decrease (Rosenzwieg. and Tubiello, 1997). • Apart from that, Mediterranean environments, the ecosystem, are characterized by a double stress (Terradas and Savé 1992): In summer, low soil hydric availability, together with high vapour pressure deficits at atmospheric level, bring inhibitions in plants growth and different negative effects in their development (Di Castri and Money 1973, Savé et. al 1999). • Despite the value of the different components of global change, the really important, it’s their integral, drought. • Predictions arising from different models for generating climate change scenarios showed as the Central American and Mediterranean regions would be affected by drought periods half length (4 - 6 months) and long (more than 12 months), and 3 and 8 times more frequents than at present (Sheffield and Wood 2008).

12. Vulnerability of urban green spaces • All the organisms, the plants, must be affected by stress, but not all and always are vulnerable to them. The most important stresses (Levitt 1980) are: • Abiotics: drought, denial, salinity, high, low, chilling and freezing temperatures, high radiation, ozone, mineral deficiencies, etc. • Biotics: insects, fungi, bacteria, viruses, elicitors, competitivity among species. • Anthropogenic: air (O3, NOx, SO2, aerosols), water (salinity, microbiology, heavy metals, drugs…) and soil (heavy metals, structure loss …) pollution, herbicides, acid rain, dry deposition, tourism … • Global change causes the combination of many of them in the same space and at the same time, which can cause synergic effects on vegetation, on crops.

13. Vulnerability of urban green spaces Factors that can act more directly on productivity, in gardening and landscaping are: • Temperature increase can produce an increase in ETP, in soil respiration, in the amount of organic matter which, at the same time, reduces soil’s capacity to act as water storage and source for vegetation (Schultz 2000). • The increase of CO2 must increase productivity and the efficient use of water, therefore, plants finally develop photosynthesis regulation and productivity returns to the original values or to inferior ones (Drake et al. 1997; Long et al.2004). • The increase in UV radiation produces important morphological, physiological and biochemical changes on vegetation to try avoiding negative effects. Despite the negative effects on growth, this stress can increase flavonoids and some antioxidants biosynthesis (Jensen et al. 1998). • Drought causes growth reduction but, in general, in the Mediterranean area, this appears together with other stresses and, consequently, the effects can be modified by the interactions (Shaver et al.2000).

14. Vulnerability of urban green spaces • Broadly speaking, other stresses are the appearance of pests, illnesses and weeds, which can go from being mere anecdotes to having quite a significance in crops, gardens, etc. due to global change (Lipa, 1997, 1999). • No doubt, environmental stresses are the main cause for productivity loss, thus current crops are reduced from 3 to 7 times with regard to their potential productivity. • Abiotic stresses and competitivity with weeds represent 9% of this reduction, illnesses 6% and insects 4%. Essentially, all crops are seasonally or yearly affected by drought, flooding, frezing or cold (Faust 1986).

15. Vulnerability of urban green spaces • Plants have developed three basic models to resist stress: • AVOIDANCE • TOLERANCE • ESCAPE

16. Vulnerability of urban green spaces • Plant response according to the gradual development of hydric stress (De Bradford and Hsiao 1982).

17. Vulnerability of urban green spaces • The main characteristic of green plants is the assimilation of CO2(Cowan 1978), all the other physiological characteristics (vacuole, cuticle, …) are secondary (Larcher 1980, 1995, 2003; Kartiens 1996 ). • Plants need to keep their stomas open in very dry environments, consequently, they continuously lose water (transpiration) and a continuous water flow is established between the soil and the atmosphere (Passioura 1982, 1988, 2001). • All environmental conditions cause hydric deficits in tissues, cause stress ... • Stress describes adverse environmental conditions for normal growth. These conditions, particularly their combination in a short time, can cause important stresses to plants, to gardens.

18. Vulnerability of urban green spaces • A. Relation between stress and response in a system with no hardening capacity. • B. Relation between stress, its duration and the response to it in a system capable of adapting and hardening (Schulze et al. 2005. Lichtenthaler 1998; Savé 2009).

19. Vulnerability of urban green spaces From our point of view, with the present conditions and the potentially future ones, the following solutions can be considered: • Adapting vegetal material to its designated location and expected use, considering its ecophysiological characteristics. • Improving soil water storage and fertility • Increasing water use efficiency by means of methods and systems that integrate our needs as users with vegetal material and water availability. • 3.1.- Sensors to help in agronomical decision making. • 3.2.- Regenerated water.

20. Vulnerability of urban green spaces 1.- Adapting vegetal material

21. Vulnerability of urban green spaces Relation between cuticular transpiration and leaf perimeter/foliar area and specific foliar weight in 16 Quercus species (a= 0.05)(Savé, Biel, De Herralde, Roberts and Evans 2003)

22. Potential (MPa) Recovery time (min) Vulnerability of urban green spaces Limitations to hardening: Effects of maximum stress in the recovery of Quercus coccifera trees(Biel, De Herralde & Savé 2002)

23. Vulnerability of urban green spaces Potential ecophysiological patters variability in Crepis triassi

24. Vulnerability of urban green spaces Could be the root system of cultured plants an important carbon sink under global change conditions? (Savé et al. 2009) Results show that vegetation biomass is generally accumulated aboveground in relation to belowground , independently of species, age and agronomical practices (R2= 0.988; n= 1047; sig>0, 0001).   Consequently the main important carbon sink in crops and gardens under Mediterranean conditions is the aerial biomass, which in general, due to agronomical practices has a short life span, because an important part of it is removed every year . In this way agricultural practices could play an important role to improve carbon sink by roots. Also, composting and use biomass as energy source, building materials, among others from aboveground biomass, are interesting alternatives to regulate the carbon cycle of biomass produced from agriculture, gardening and landscaping.

25. Vulnerability of urban green spaces Barcelona’s coastal is 13 km longer, which included beaches, commercial and sportive harbors, 2 rivers and a drainage network of about 15 streams with a marked Mediterranean water regime. These characteristics promote a narrow relationship between urban metabolism and sea water properties. These is a fragile equilibrium among different interests (tourism, beach uses, gardens, pollutants, water quality, harbors).

26. Vulnerability of urban green spaces Polluted marine aerosol effect on coastal vegetation

27. Vulnerability of urban green spaces The current EU yearly detergent consumption is 50 kg. per capita.

28. Physiopathy detected in Barcelona’s Olympic village during 1991 Vulnerability of urban green spaces Contaminated marine spray has negative foliar effects (Diamantopoulos et al. 2001; Marull et al 1997). This photo was taken in the month of April previous to the 1992 Barcelona Olympics.

29. Vulnerability of urban green spaces This photo was taken in the month of April previous to the 1992 Barcelona Olympics.

30. Vulnerability of urban green spaces Effects of polluted marine spray in cuticular transpiration rate of plants, hardened or not, of Metrosideros excelsa and Myoporum laetum(Diamantopoulos, Biel, De Herralde & Savé 2001).

31. Vulnerability of urban green spaces Pinus halepensis Effects of contaminated marine spray and ozone on Pinus halepensis (Diamantopoulos, Heredia, Sanz, Bayona, Escarre, Biel & Savé 2002) Above: Percentage of affected acicular leaves of the first verticile. Standard average and error (n = 5) Below: Percentage of affected acicular leaves of the first verticile. Standard average and error (n = 5)

32. Vulnerability of urban green spaces Control and reduction of pesticide’s use in parks, gardens and landscape restorations • Another point of interest of urban green areas, is and will be their management based on sustainability criteria and the use of pedagogic management. • Global change could promote new pest and/or modified the phenological behavior of old and new pests. • Thus, the criteria for integrated production, biological control and therefore the reduction of pesticide use is the standard commonly used in public parks of the first world. • So plant – pest relationship is the key to develop this kind of production, control.

33. Vulnerability of urban green spaces Physiological explanation of white fly egg mortality (Castañe and Savé 1993).

34. Vulnerability of urban green spaces Relation insect (Macrolophus caliginosus) vs Mediterranean ruderal plants at foliar level(Savé, Comas, García, Labarta, Alomar, Gabarra, Arnó and Biel 2008).

35. Vulnerability of urban green spaces Production and water-use efficiency of Lotus creticus and Cynodon dactylon growing in pure stand or in competitive mixture under two levels of irrigation(Vignolio et al 2002).

36. Vulnerability of urban green spaces Visitors, invaders…? It depends on many things, ourselves among them (IRTA/UCDavis 2007).

37. Vulnerability of urban green spaces 2.- Improving soil water storage and fertility.

38. Could be drought in our parks attibutable to rainfall reduction, or ETP increase,...?: Evolution of rainfall, ETP and centigrade degree /day in a temporal serie of 65 years inTorre Marimon (Caldes de Montbui, Barcelona, Spain).(Ruiz, Crivilles i Savé. 2008)

39. Is there soil, or substrate?. Plants living in/on, but it’s very different, among others plant water relations are very different, hydrological cycle its absolutely modified similarly than biological fertility. R. Cots-Folch et al. . 2006. Agriculture, Ecosystems and Environment 115 88–96

40. The Spanish region with high number of mining is Catalonia, due to the big number of quarries, which according law must be restored. Are we restoring or making up the landscape?.

41. Effects of root volume restriction on growth of 5 years old Platanushispànica (Biel et al 2007)

42. Vulnerability of urban green spaces Once constructed, the ditches are filled with their own soil and slow release fertilizer, in a proportion of 1/3 compost and 2/3 soil. The slow release fertilizer composition is the same in both treatments.

43. Vulnerability of urban green spaces • Treatments have increased the soil water content, which has caused a larger growth in diameter than the previous year as well as a 19 and 28% increase in the quality of the canopy for the forked soil and compost treatments in relation with the control, and a 19% increment in the cubication of the aerial parts, in compost treatments in relation to the others. • It is considered that growth has not improved more clearly because of the trees age, which doesn’t allow to modify their growth rhythm however much the conditions are improved.

44. MC NMC M 500 70 50 NM 500 MS 45 M 300 60 40 NM 300 NMS 50 35 30 40 Rhr (MPa·s·cm-2)·10-4) Soil coverage (%) 25 30 20 15 20 10 10 5 0 0 -5 0 5 10 15 20 25 30 A S O N D J F M A M J J Days Month Vulnerability of urban green spaces Hardening by mychorizas: Effects of pluviometry in the % of soil coverage in plants inoculated or not with VAM (Biel, Estaun and Savé 2002)

45. Vulnerability of urban green spaces Effects of soil temperature in root hydraulic resistance and respiration (Biel, Estaun and Savé 1996)

46. Vulnerability of urban green spaces • Increasing efficiency in the use of water by means of methods and systems that integrate our needs as users with vegetal material and water availability. • 3.1.- Sensors to help in agronomical decision making. • 3.2.- Regenerated waters.

47. Spectroradiometer 20 cm 0.01m2 R900 NIR R WI - = = NDVI NIR R970 R + 0.4 Reflectance 0.2 0.0 400 500 600 700 800 900 1000 UV IR wavelength(nm) Leaf RWC 0.001m2 Digital image 1m2 90º HUE(º) 0º 180º 270º Green area (%) Vulnerability of urban green spaces Objective: Evaluation of digital images as indicators of hydric state(Casadesus et al 2005). Soil matric potential

48. Vulnerability of urban green spaces Relation between RWC and NDVI with the hydric potential of the substrate in to species of grass (Llobet et al. 2006).

49. 40 60 100 100 100 80 80 60 60 Green area (%) Festuca 40 40 Hue (º) r = 0.94* 20 20 r = 0.92* 0 0 0 20 40 60 80 100 0 20 40 60 80 100 Soil matric potential (kPa) Soil matric potential (kPa) 100 100 80 80 40 60 60 60 Green area (%) Cynodon 100 40 40 Hue (º) r = 0.43 20 20 r = 0.29 0 0 0 20 40 60 80 100 0 20 40 60 80 100 Soil matric potential (kPa) Soil matric potential (kPa) * Statistical significance p < 0.1 Vulnerability of urban green spaces Relation between hue and green area with the hydric potential of the substrate in two species of grass (Llobet et al. 2006).

50. Vulnerability of urban green spaces Conclusions • All evaluated parameters present inferior values in Cynodón with regard to Festuca, which indicates a different adaptation to hydric restriction, as their ecophysiological characteristics define (Harivandi 1998, Tyer & Zeiger 2002). • RWC measures prove insensitive to changes in matric soil, which is attributable to the used sampling and the agronomical management of the grass. • NDVI showed a similar response to the one described for RWC, which concurs with the previous results (Peñuelas & Filella 1993). This parameter is only sensitive to values inferior to 70% RWC. WI shows the same behaviour for the same reasons (Peñuelas et al 1993, 1995 a, b). • Colour hue and coverage, the green area, showed a significantly negative relation with soil water tension in Festuca, whereas it seemed less insensitive in Cynodon (Casadesus et al 2005), which can be attributed to the different sensitivity to drought of these two species (Harivandi 1998; Tyer & Zeiger 2002;Vignolio et al 2000, 2002 y 2005).