Títol: Effects of paddy management (conventional vs. organic) on the diversity of aquatic macroinvertebrates and the provisioning of biological pest control
Tutor/a o Cotutor/a: VERDU GONZALEZ, ANTONIO MARIA
Departament: DEAB
Títol:
Effects of paddy management (conventional vs. organic) on the diversity of aquatic macroinvertebrates and the provisioning of biological pest control
Data inici oferta:
29-09-2021
Data finalització oferta:
29-04-2022
Descripció del contingut i pla d'activitats:
El treball tractarà sobre la gestió dels arrossars del Delta de
l'Ebre, on la gran majoria d'aquests i de forma
tradicional estan sent tractats amb herbicida per tal de tenir el
sòl nu de vegetació any rere any. Aquest fet juntament amb el
monocultiu de l'arròs donat per ser l'espècie més adaptada a les
condicions d'entollament, salinitat i climàtiques de la zona,
deixa al delta de l'Ebre en una situació de risc de cara a la
biodiversitat de la zona que pot acabar afectant un dels
ecosistemes més característics de Catalunya.
Està previst fer uns assajos a camp a prop de l'IRTA d'Amposta on
es faran diverses repeticions a diversos arrossars i mostrejar
els macroinvertebrats aqüàtics. S'avaluaran diversos paràmetres
relacionats amb la biodiversitat i es mostraran els resultats i
les conclusions relacionades amb el control biològic de plagues a
les quals s'ha arribat.
Overview (resum en anglès):
There is a global trend of biodiversity loss that is threatening more than a million
species. Scientists, politicians and society are increasingly aware of the worrying data and
the negative consequences that this loss can cause in the provision of ecosystem services,
present in almost all biological relationships. Among the main factors of this negative
trend appears the agricultural intensification, based on the use of agrochemicals in all
remarkable production processes.
Organic farming has emerged as the main production alternative, trying to palliate
the potential negative effects of chemical inputs used by conventional agriculture. The
scientific community has not yet reached a full resolution on the benefits of this
alternative system and agrees that this is a topic of the utmost importance that is still
under-studied today. This TFG evaluates experimentally the effect of two types of rice
production (conventional vs. ecological) on the diversity of the community of aquatic
macroinvertebrates associated with the water surface of the rice fields. In addition, the
relationship between rice field management, the diversity of the macroinvertebrate
community, specifically aquatic predators, and the biological control of chironomids, a
crop pest with an important agricultural impact, is evaluated.
Our results show a reduction in the richness and abundance of
macroinvertebrates as well as aquatic predators in conventional rice fields. This loss of
diversity is accompanied by a lower efficiency in the predation rate of chironomids. Those
results, therefore, suggest that a reduction in the use of agricultural inputs (not
necessarily zero use) can help to reduce the impact of agriculture on biodiversity and
improve the efficiency of important ecosystem services such as biological control of pests.