The intercropping of poplar trees for industrial wood production with herbaceous crops has been practiced in Italy until the late 70s. It is currently adopted for poplar cultivation in China and India, and in Europe it is studied in the framework of modern agroforestry, for the important environmental and productive values of the sustainable intensification of agriculture. Such intercropping forms are now named silvoarable or alley cropping systems. Tree rows intercropped with agricultural crops increase organic matter and soil carbon, mitigating climate change. Tree roots reduce nitrates leaching, with strong phytoremediation actions of water and soil from many contaminants. For the aforementioned benefits, the Rural Development Plans of some Regions provide funding for the establishment of new silvo-arable systems. This paper reports the studies conducted within the European project AGFORWARD (2014-17, www.agforward.eu) at a silvoarable site with hybrid poplar (I214 clone) and English oak (Quercus robur L.). The site was established in 2014 by the Casaria Farm (48°08'30'' N; 11°30'13'' E), in the Po valley, municipality of Masi, Padua. This work is acollaboration of various stakeholders: VenetoAgricoltura and CNR IBAF of Porano (both partners of the AGFORWARD project), the Casaria Farm and the AIAF (Italian Association of Agroforestry). The silvoarable area is about 9 ha large, on reclaimed alluvial land with Ferrarese drainage system, i.e. with permanent drainage ditches with a depth of 1 m and spaced at 30-35 m. The tree rows, planted along the outer ditch edge, have an orientation of 5° N. In the silvo-arable area, nine experimental transects of 10 x 30-35 m were formed, for running measurements on tree growth and intercrops yield, and for studying the interactions between tree and herbaceous components for solar radiation, soil moisture and nitrogen. In silvoarable systems, in order to be technically sustainable and economically profitable, there must be synergistic or complementary interactions higher than competitive ones in the use of primary resources (water, phyto- nutrients and solar radiation). At the end of the fourth vegetative season, the poplar trees have reached a height of 9 m 0.5 standard error of mean -sem) with a diameter of 11 cm (0.29 sem). The quality of the poplar timber, assessed according to the stem shape, height of canopy insertion (5.6 m, 0.15 sem) and trunk eccentricity (3.02%, 0.39 sem), is suitable for the more profitable industrial uses of poplar timber, for peeling and sawing, despite the large planting density (30 poplar trees per ha). As far as expected, oak trees have a growth rate much slower than poplars, with a height of about 1.8 m (1.23 sem) at the fourth season, and with 100% of survival. The oak trees, 5 m away on the row from the poplars, do not seem to be negatively influenced by poplar trees shade. Yield of herbaceous crops was, in dry matter (dm), 14.4 t dm ha-1 (0.78 sem) for sugar beet in 2015, and 4.8 (0.1 sem) and 4 (0.14 sem) t dm ha-1, for durum wheat and soybean, respectively, in 2016 with organic management. The presence of trees does not hinder the operation of farm machineries for crops management, nor the size of trees is such as to significantly shade crops, whose production does not indicate significant differences between the central and lateral areas across intercrop alleys. In 2014 and 2015, hemispherical photos indicate solar radiation values being 98.8 (0.23 sem) and 97.7% (0.54 sem) across intercrop alley compared to full sun. These values are compatible with shading indexes that do not affect the availability of radiant energy for the associated crops. Studies on the stable isotopes of water oxygen (?18O) and nitrogen (?15N) show early positive synergistic interactions between herbaceous crops and trees with respect to the use of soil water and nutrients, with poplar trees using the soil moisture in the deep layers and, probably, reducing nitrogen leaching. In conclusion, results show that between trees and associated herbaceous crops, during the years of study, it prevails complementary interactions for light and water, and synergistic ones for nitrogen. The silvoarable site is currently used for extension activities (currently in the H2020 AFINET project, www.afinet.eu), to verify the interest of farmers for this form of poplar cultivation, able to combine "food and wood security" with environmental protection.
La consociazione del pioppo da industria con le colture erbacee e? stata una pratica colturale frequentemente utilizzata dai pioppicoltori italiani sino agli ultimi anni '70. E' attualmente adottata nella pioppicoltura di Cina ed India, ed in Europa e? oggetto di studio nell'ambito della moderna agroforestry, per le importanti valenze ambientali e produttive della nuova agricoltura ad intensificazione sostenibile. I filari arborei intervallati alle colture agricole aumentano la sostanza organica ed il Carbonio nel suolo, mitigando i cambiamenti climatici. Le radici degli alberi riducono la lisciviazione dei nitrati, con una forte azione di fito-depurazione di acqua esuolo da molti contaminanti. Per i suddetti benefici, i Piani di Sviluppo Rurale di alcune Regioni prevedono finanziamenti per i sistemi silvo-arabili con pioppo. Il presente contributo riporta gli studi condotti nell'ambito del progetto Europeo AGFORWARD (2014-17) presso un impianto silvo-arabile di pioppo ibrido (clone I214) e farnia (Quercus robur L.) realizzato nel 2014 dall'azienda Casaria (48°08'30'' N; 11°30'13'' E), nella Pianura padano-veneta, comune di Masi, prov. Padova). Il lavoro ha visto la collaborazione di vari stakeholders: Veneto Agricoltura e CNR IBAF di Porano (partner del progetto AGFORWARD, www.agforward.eu), l'azienda Casaria e l'AIAF (Associazione Italiana Agroforestazione). L'impianto e? stato realizzato in un appezzamento di circa 9 ha, su terreno di bonifica con sistemazione alla Ferrarese, cioe? con scoline di drenaggio permanenti con 1 m di profondita? e distanziate a 30-35 m. I filari arborei, piantati lungo il bordo esterno della scolina, hanno un orientamento di 5° N. Nell'impianto silvo-arabile sono stati costituiti 9 transetti sperimentali di 10 x 30-35 m, su cui sono state condotte le osservazioni per quantificare l'accrescimento degli alberi, le produzioni delle colture erbacee e le interazioni, tra componenti arboree ed erbacee, per energia radiante, l'umidita? del suolo e l'azoto. Affinche? un sistema silvoarabile sia tecnicamente sostenibile ed economicamente remunerativo devono sussistere interazione sinergiche o complementari rispetto a quelle competitive nell'uso delle risorse primarie (acqua, fito-nutrienti e radiazione solare). Alla fine della quarta stagione vegetativa il pioppo ha raggiunto un'altezza di 9 m (0.15 errore standard -es) con diametro a petto d'uomo di 11 cm (0,29 es). La qualita? del legno del pioppo, valutata in base alla forma del fusto, altezza inserzione rami (5,6 m; 0,15 es) ed eccentricita? del fusto (3,02%, 0,39 es), risulta idonea agli usi industriali piu? remunerativi, per sfogliatura e segagione, nonostante gli ampi sesti d'impianto (30 piante di pioppo ad ha). La farnia, come previsto, presenta ritmi d'accrescimento molto piu? lenti del pioppo, con un'altezza di circa 1.8 m (1,23 es) alla quarta stagione, e con il 100% d'attecchimento e sopravvivenza. La farnia, a 5 m di distanza sulla fila dai pioppi, non sembra essere al momento influenzata dall'ombreggiamento dei pioppi. La produzione delle colture erbacee conosciate e? risultata, in sostanza secca (ss), di 14,4 t ss ha-1 (0,78 es) per la barbabietola da zucchero nel 2015, e di 4,8 (0.1 es) e 4 (0.14 es) t ss ha-1, per grano duro e soia in biologico nel 2016. La presenza degli alberi non ostacola l'operazione dei mezzi meccanici per la gestione delle colture, ne? la dimensione degli alberi e? tale da ombreggiare significativamente le colture, le cui produzioni non indicano differenze significative tra la fascia centrale e fasce laterali delle colture consociate. Nel 2014 e 2015 le foto emisferiche indicano valori di luminosita? pari al 98,8 (0.23 es) e 97,7% (0.54 es) rispetto al pieno sole. Tali valori sono ampiamente compatibili con indici di ombreggiamento che non influiscono sulla disponibilita? di luce delle colture consociate. Gli studi sugli isotopi stabili dell'ossigeno dell'acqua (?18O) e dell'azoto (?15N) mostrano precoci interazioni sinergiche positive tra le colture erbacee e gli alberi riguardo all'acqua e alle sostanze nutritive del suolo, con alberi di pioppo che utilizzano l'umidita? del suolo negli strati piu? profondi del suolo e riducono la lisciviazione dell'azoto. In conclusione, gli studi condotti, dimostrano che tra alberi e colture erbacee consociate, negli anni di studio prevalgono interazioni complementari per luce ed acqua, e sinergiche per l'azoto. L'impianto studiato e? oggetto di azioni divulgative (attualmente nel prog. H2020 AFINET, www.afinet.eu), per verificare l'interesse degli agricoltori per questa forma di pioppicoltura, in grado di coniugare "food e wood security" con la tutela ambientale.
Sistemi silvo-arabili di pioppo da industria e farnia. Il caso studio dell'azienda Casaria nel Polesine
Pierluigi Paris;Andrea Pisanelli;Marco Lauteri;Luca Leonardi;Marcello Cherubini;francesca Chiocchini;Marco Ciolfi;Luciano Spaccino;
2018
Abstract
The intercropping of poplar trees for industrial wood production with herbaceous crops has been practiced in Italy until the late 70s. It is currently adopted for poplar cultivation in China and India, and in Europe it is studied in the framework of modern agroforestry, for the important environmental and productive values of the sustainable intensification of agriculture. Such intercropping forms are now named silvoarable or alley cropping systems. Tree rows intercropped with agricultural crops increase organic matter and soil carbon, mitigating climate change. Tree roots reduce nitrates leaching, with strong phytoremediation actions of water and soil from many contaminants. For the aforementioned benefits, the Rural Development Plans of some Regions provide funding for the establishment of new silvo-arable systems. This paper reports the studies conducted within the European project AGFORWARD (2014-17, www.agforward.eu) at a silvoarable site with hybrid poplar (I214 clone) and English oak (Quercus robur L.). The site was established in 2014 by the Casaria Farm (48°08'30'' N; 11°30'13'' E), in the Po valley, municipality of Masi, Padua. This work is acollaboration of various stakeholders: VenetoAgricoltura and CNR IBAF of Porano (both partners of the AGFORWARD project), the Casaria Farm and the AIAF (Italian Association of Agroforestry). The silvoarable area is about 9 ha large, on reclaimed alluvial land with Ferrarese drainage system, i.e. with permanent drainage ditches with a depth of 1 m and spaced at 30-35 m. The tree rows, planted along the outer ditch edge, have an orientation of 5° N. In the silvo-arable area, nine experimental transects of 10 x 30-35 m were formed, for running measurements on tree growth and intercrops yield, and for studying the interactions between tree and herbaceous components for solar radiation, soil moisture and nitrogen. In silvoarable systems, in order to be technically sustainable and economically profitable, there must be synergistic or complementary interactions higher than competitive ones in the use of primary resources (water, phyto- nutrients and solar radiation). At the end of the fourth vegetative season, the poplar trees have reached a height of 9 m 0.5 standard error of mean -sem) with a diameter of 11 cm (0.29 sem). The quality of the poplar timber, assessed according to the stem shape, height of canopy insertion (5.6 m, 0.15 sem) and trunk eccentricity (3.02%, 0.39 sem), is suitable for the more profitable industrial uses of poplar timber, for peeling and sawing, despite the large planting density (30 poplar trees per ha). As far as expected, oak trees have a growth rate much slower than poplars, with a height of about 1.8 m (1.23 sem) at the fourth season, and with 100% of survival. The oak trees, 5 m away on the row from the poplars, do not seem to be negatively influenced by poplar trees shade. Yield of herbaceous crops was, in dry matter (dm), 14.4 t dm ha-1 (0.78 sem) for sugar beet in 2015, and 4.8 (0.1 sem) and 4 (0.14 sem) t dm ha-1, for durum wheat and soybean, respectively, in 2016 with organic management. The presence of trees does not hinder the operation of farm machineries for crops management, nor the size of trees is such as to significantly shade crops, whose production does not indicate significant differences between the central and lateral areas across intercrop alleys. In 2014 and 2015, hemispherical photos indicate solar radiation values being 98.8 (0.23 sem) and 97.7% (0.54 sem) across intercrop alley compared to full sun. These values are compatible with shading indexes that do not affect the availability of radiant energy for the associated crops. Studies on the stable isotopes of water oxygen (?18O) and nitrogen (?15N) show early positive synergistic interactions between herbaceous crops and trees with respect to the use of soil water and nutrients, with poplar trees using the soil moisture in the deep layers and, probably, reducing nitrogen leaching. In conclusion, results show that between trees and associated herbaceous crops, during the years of study, it prevails complementary interactions for light and water, and synergistic ones for nitrogen. The silvoarable site is currently used for extension activities (currently in the H2020 AFINET project, www.afinet.eu), to verify the interest of farmers for this form of poplar cultivation, able to combine "food and wood security" with environmental protection.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
