Relationships between management practices and ground-active invertebrate biodiversity in New Zealand kiwifruit orchards

Abstract

1 Increasing the biodiversity of agro-ecosystems may benefit rare and native species, improve ecosystem services and increase grower incomes through higher value eco-verified orchard products. Previous research has shown that the taxonomic richness of invertebrates in organic kiwifruit orchards is significantly higher than in integrated pest management (IPM) orchards, suggesting that orchard management practices may affect invertebrate biodiversity. 2 We used multiple regression models to investigate the relationships between the diversity of ground-active invertebrates in three functional groups [natural enemies, herbivores, detritivores (including fungivores)] and 14 management practices used on 10 organic and 10 IPM orchards. 3 The significant relationships between the management variables and invertebrate communities differed for each functional group: (i) the greater diversity of natural enemy and detritivore taxa in organic orchards was significantly correlated with less toxic agrichemical sprays; (ii) greater amounts of vegetative ground cover in the organic orchards was significantly correlated with a greater diversity of detritivore and herbivore taxa; and (iii) differences in magnesium application rates explained some of the variation in the herbivore and detritivore communities. 4 Management practices on IPM kiwifruit orchards could be altered to increase invertebrate biodiversity, which also may improve ecosystem services on these orchards; however, care should be taken to ensure that pest populations do not also benefit from these changes.

Case study of microarthropod communities to assess soil quality in different managed vineyards

“…Hole et al, 2005;Kromp, 1990;Liebig and Doran, 1999;Reddersen, 1997). Less data and evidence are available in the evaluation of the artropod biodiversity to compare organic and IPM managements (Landi et al, 2014;Todd et al, 2015). The organic and integrated systems showed higher soil quality and potentially lower negative environmental impact than the conventional system (Mazzoncini et al, 2010;Reganold et al, 2001).…”

“…Soil quality characteristics such as stability, resilience to disturbance or stress and biodiversity (van Bruggen and Semenov, 2000) are directly influenced by land use and management practices (DeFries et al, 2004). Assessment of soil quality is a complex issue that depends on the combination of all physical, chemical and biological properties.…”

“…Several studies have documented the importance of the soil biota for soil quality and vitality , as well as its potential for reflecting anthropogenic disturbances (Paoletti et al, 1991;Van Straalen, 1998). In an agricultural context, the combination of productive goals and sustainable land uses protecting both soil and biodiversity is essential in order to prevent the decline of soil fauna communities (Menta et al, 2011).…”

“…Therefore, soil quality can be assessed by physical, chemical and microbiological properties of soil together with the abundance and diversity of edaphic fauna (nematodes, Acari, Collembola, Symphyla, Chilopoda, Pauropoda, enchytraeids, earthworms); furthermore, the determination of community structure adds significant information on the soil status (Cole et al, 2006;De Goede and Brussard, 2002;Duelli and Obrist, 2003;Menta et al, 2008;van Straalen, 1998;Yan et al, 2012). In a well-balanced soil, mesofauna is highly biodiversified and occupies all trophic levels within the soil food webs (Ruf et al, 2006).…”

“…The literature suggests that organically managed fields contain a greater abundance and diversity of arthropods than conventionally managed fields (Berry et al, 1996;Hole et al, 2005;Pimentel et al, 2005;Reddersen, 1997) and that changing from conventional to organic farming leads to a gradual increase in biodiversity (van Diepeningen et al, 2006).…”