Ecosystem Services on New Zealand Arable Farms

Researchers have estimated the total economic value of global ecosystem goods and services showing that a significant portion of humanity's economic well being is unaccounted for in conventional GNP accounting (Constanza et al., 1997). To demonstrate this point, authors have conventionally used highly aggregated landscape units for analysis (e.g., biomes), and average, not marginal values, of each ecosystem good or service are estimated for each unit using value transfer methodologies (Wilson et al., 2004). For example, Patterson and Cole (1999a, b) replicated the Constanza et al., (1997) approach by estimating economic values for Waikato and New Zealand ecosystem goods and services associated with standard land cover classes including horticulture, agriculture and cropping. As a result, Patterson and Cole (1999b) argue that only five ecosystem services associated with cropping have non-zero value. One of the reasons for this low number of non-zero values assorted with arable lands is that the original economic studies used by Patterson and Cole, are heavily weighted towards natural and undisturbed ecosystems rather than disturbed systems like agricultural or urban landscapes. To address this issue, more recently researchers have noted that many landscapes are actively modified by humans who seek to realise economic gain and this topic is thus an important one because in the 21st century, many of our homes, workplaces and recreational spaces are embedded within, or adjacent to, landscape mosaics that are to a greater or lesser degree affected by the conscious efforts of people to harness goods and services provided by ecological systems (Palmer et al., 2004). An engineered or designed ecosystem is one that has been extensively modified by humans to explicitly provide a set of ecosystem goods and services including more fresh water, trees, and food products and fewer floods and pollutants. These modified landscapes provide a range of ecosystem goods and services, particularly food production as farmers seek to maximize commercial gain from land use. The current paper examines issues in valuation of ecosystem goods and services derived from land used for arable farming in New Zealand and proposes ways to provide more detailed estimates of the flow and value of the flow of ecosystem services provided.Ecosystem management, Arable farming, Engineered ecosystem, Agricultural and Food Policy, Community/Rural/Urban Development, Crop Production/Industries, Environmental Economics and Policy, Farm Management, Land Economics/Use,

Values of Ecosystem Services Associated with Intense Dairy Farming in New Zealand

The increase in greenhouse gas emissions and degradation of water quality and quantity in waterways due to dairy farming in New Zealand have become of growing concern. Compared to traditional sheep and beef cattle farming, dairy farming is more input intensive and more likely to cause such environmental damage. Our study uses choice modeling to explore New Zealanders' willingness to pay for sustainable dairy and sheep/beef cattle farming. We investigate respondents' level of awareness of the environmental degradation caused by dairy farming and their willingness to make trade-offs between economic growth and improvements in the level of ecosystem services associated with pastoral farming.ecosystem services, greenhouse gas emissions, dairy farming, choice modeling, Environmental Economics and Policy, Livestock Production/Industries,

The ecology of predatory hoverflies as ecosystem-service providers in agricultural systems

The main contemporary challenge for agriculture is to meet the food demands of the increasing world population while becoming more environmentally sustainable. One way to achieve this is through the promotion of functional biodiversity and the ecosystem (nature’s) services (ES) that it can provide. The Syrphinae subfamily is a widespread group of hoverflies with a high potential for that service. Hence, the present review aims to synthesize the existing literature on this group. This review is divided in three main sections. First, we focus on those aspects of the ecology of hoverflies that are relevant to their role in biological control. These are divided into nutrition, feeding preferences and prey detection of the different developmental stages, overwintering and the effect of landscape on their dispersal and efficacy. Second, we review the ES that predatory hoverflies can provide, particularly pollination and biological control. Finally, we discuss those farming practices that can affect the effectiveness of these Diptera as providers of ES. Overall, this review highlights the potential, as well as limitations and current gaps in knowledge, for enhancing the efficacy of hoverflies as ecosystem-service providers in agricultural systems.info:eu-repo/semantics/acceptedVersio

Bactericera cockerelli (Sulc), a potential threat to China's potato industry

The potato psyllid Bactericera cockerelli (Hemiptera: Triozidae) has recently emerged as a serious pest of potatoes and other solanaceous crops. It causes direct feeding damage and also vectors Candidatus Liberibacter solanaceaerum (Lso), a pathogen that causes zebra chip disease in potatoes and which potentially costs growers millions of dollars each year. Such producers rely on frequent sprays of pesticides for psyllid control but the results are unsatisfactory and there are negative side effects. The psyllid has spread beyond its native range in southwest US and northern Mexico to Canada, El Salvador, Honduras, Guatemala and Nicaragua via medium to long range dispersal flights perhaps aided by wind currents, and through anthropogenic means. It was accidentally introduced into New Zealand in 2006 and most recently Australia, most likely through the importation of infested plant material. This review summarizes information from studies on the biology, impact and management of B. cockerelli, and highlights the imminent risk of this insect and its associated pathogen invading China, the world's largest producer of fresh potatoes. Development of risk maps leading to increased surveillance, could prevent or delay an incursion and facilitate early detection or eradication should this occur. Long-term management with Lso-tolerant potato cultivars and psyllid control using the parasitic wasp Tamarixia triozae and other natural enemies should be pursued, rather than depending on synthetic pesticides.info:eu-repo/semantics/publishedVersio

Assessing pollinators' use of floral resource subsidies in agri-environment schemes: An illustration using Phacelia tanacetifolia and honeybees

ABSTRACT Background: Honeybees (Apis mellifera L.) are frequently used in agriculture for pollination services because of their abundance, generalist floral preferences, ease of management and hive transport. However, their populations are declining in many countries. Agri-Environment Schemes (AES) are being implemented in agricultural systems to combat the decline in populations of pollinators and other insects. Despite AES being increasingly embedded in policy and budgets, scientific assessments of many of these schemes still are lacking, and only a few studies have examined the extent to which insect pollinators use the floral enhancements that are part of AES and on which floral components they feed (i.e., pollen and/or nectar). Methods: In the present work, we used a combination of observations on honeybee foraging for nectar/pollen from the Californian annual plant Phacelia tanacetifolia in the field, collection of pollen pellets from hives, and pollen identification, to assess the value of adding phacelia to an agro-ecosystem to benefit honeybees. Results: It was found that phacelia pollen was almost never taken by honeybees. The work here demonstrates that honeybees may not use the floral enhancements added to a landscape as expected and points to the need for more careful assessments of what resources are used by honeybees in AES and understanding the role, if any, which AES play in enhancing pollinator fitness. Discussion: We recommend using the methodology in this paper to explore the efficacy of AES before particular flowering species are adopted more widely to give a more complete illustration of the actual efficacy of AES

A Perspective on the Consequences for Insect Herbivores and Their Natural Enemies When They Share Plant Resources

Thousands of insect species consume both animal and plant-derived food resources. However, little recognition is given to the fact that omnivory is a general feeding strategy common to all higher trophic levels. Species in multitrophic interactions can all directly rely on the same plant resources. Nonetheless, little is known about the effect of a change in the relative abundance of a shared plant resource on trophic dynamics. Here we describe how a relative change of resource availability can affect multitrophic interactions and we emphasise its importance. Changes in multitrophic interactions can be induced by unequal alterations of individual fitness across trophic levels, possibly leading to changes in population structure of interacting species. At least ten ecological mechanisms can be involved and these are explored here. It is concluded that shared plant resources that are differentially used over several trophic levels have the potential to modify community structure and energy flow within food webs and ecosystems in more complex ways than previously recognised. The synthesis presented here provides an understanding of this complexity and can lead to improved deployment of biodiversity when manipulating food webs to protect ecological communities or to enhance ecosystem services such as biological control of agricultural pests

Pyrosequencing of prey DNA in faeces of carnivorous land snails to facilitate ecological restoration and relocation programmes

International audienc

When mining the habitat of a rare carnivorous landsnail leads to a wealth of knowledge gain for the whole genus

Powelliphanta is a genus of large land snails endemic to New Zealand. The twelve recognised species and numerous sub-species in that genus are known for their bright and colourful shells as well as their carnivorous habits. Although they are found in a variety of habitat types, several species and sub-species are in danger of extinction. In 2006, a new species (Powelliphanta augusta) was discovered on the footprint of New Zealand's largest opencast coalmine. Most of this snail natural habitat had been lost already and an ambitious conservation programme was established to save the species. Before conservation work began on P. augusta, little was known about the behaviour, the diet, the population structure, the life cycle, of most species in the genus. Only two peer-reviewed publications on Powelliphanta can be found on web of knowledge prior to 2007. Since then, 13 additional papers have been published, attracting 113 citations. The conservation programme around P. augusta also breathed new life in research on native earthworms, upon which the snails prey. The direct knowledge gained and the research emulation generated by the conservation programme of P. augusta had far-reaching repercussions on the ecology and conservation of New Zealand fauna and constitutes a long-term scientific compensation for the mining activities. For example, the method routinely used by the NZ Department of Conservation for estimating abundance of Powelliphanta had never been proven to be accurate. In fact, we show that on average, only 30% of snails are observed during a standard monitoring event, while the proportion of snails overlooked at each monitoring plot ranges from 10% to over 50%. We propose an alternative mark-recapture technique, which was developed to monitor the critically endangered snail P. augusta (1). Our proposed monitoring method is reliable and a practical alternative to the standard method for monitoring Powelliphanta snails. Another example lies in the detailed description of the diet of P. augusta and the development of a molecular diet analysis method later applied to another species in the genus (2). Knowledge on the diet of these species supported their successful rearing in captivity with the aim of releasing new populations in protected predator controlled areas. In this talk we will present our findings and summarise the knowledge gained on the ecology, development, captive rearing and translocation of Powelliphanta snails, which directly arose from P. augusta conservation programme. (1) Hamilton M (2015) Monitoring Powelliphanta land snails: an assessment of the current technique and the development of a new mark-recapture technique (Doctoral dissertation, Lincoln University). (2) Boyer S, Wratten SD, Holyoake A, Abdelkrim J, Cruickshank RH (2013) Using next-generation sequencing to analyse the diet of a highly endangered land snail (Powelliphanta augusta) feeding on endemic earthworms. PLoS One, 8(9), e75962peerReviewe

DOC SCIENCE INTERNAL SERIES 67

Effects of ivermectin in dairy discharges on terrestrial an